Association between Use of Exogenous Testosterone Therapy and Risk of Venous Thrombotic Events among Exogenous Testosterone Treated and Untreated Men with Hypogonadism.

PubMed

Li, Hu; Benoit, Karin; Wang, Wei; Motsko, Stephen

2016-04-01

Limited information exists about whether exogenous testosterone therapy is associated with a risk of venous thrombotic events. We investigated via cohort and nested case-control analyses whether exogenous testosterone therapy is associated with the risk of venous thrombotic events in men with hypogonadism. Databases were reviewed to identify men prescribed exogenous testosterone therapy and/or men with a hypogonadism diagnosis. Propensity score 1:1 matching was used to select patients for cohort analysis. Cases (men with venous thrombotic events) were matched 1:4 with controls (men without venous thrombotic events) for the nested case-control analysis. Primary outcome was defined as incident idiopathic venous thrombotic events. Cox regression and conditional logistic regression were used to assess HRs and ORs, respectively. Sensitivity analyses were also performed. A total of 102,650 exogenous testosterone treated and 102,650 untreated patients were included in cohort analysis after matching, and 2,785 cases and 11,119 controls were included in case-control analysis. Cohort analysis revealed a HR of 1.08 for all testosterone treated patients (95% CI 0.91, 1.27, p = 0.378). Case-control analysis resulted in an OR of 1.02 (95% CI 0.92, 1.13, p = 0.702) for current exogenous testosterone therapy exposure and an OR of 0.92 (95% CI 0.82, 1.03, p = 0.145) for past exogenous testosterone therapy exposure. These results remained nonstatistically significant after stratifying by exogenous testosterone therapy administration route and age category. Most sensitivity analyses yielded consistent results. No significant association was found between exogenous testosterone therapy and incidents of idiopathic or overall venous thrombotic events in men with hypogonadism. However, some discrepant findings exist for the association between injectable formulations and the risk of overall venous thrombotic events. Copyright © 2016 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Experience with multiple control groups in a large population-based case-control study on genetic and environmental risk factors.

PubMed

Pomp, E R; Van Stralen, K J; Le Cessie, S; Vandenbroucke, J P; Rosendaal, F R; Doggen, C J M

2010-07-01

We discuss the analytic and practical considerations in a large case-control study that had two control groups; the first control group consisting of partners of patients and the second obtained by random digit dialling (RDD). As an example of the evaluation of a general lifestyle factor, we present body mass index (BMI). Both control groups had lower BMIs than the patients. The distribution in the partner controls was closer to that of the patients, likely due to similar lifestyles. A statistical approach was used to pool the results of both analyses, wherein partners were analyzed with a matched analysis, while RDDs were analyzed without matching. Even with a matched analysis, the odds ratio with partner controls remained closer to unity than with RDD controls, which is probably due to unmeasured confounders in the comparison with the random controls as well as intermediary factors. However, when studying injuries as a risk factor, the odds ratio remained higher with partner control subjects than with RRD control subjects, even after taking the matching into account. Finally we used factor V Leiden as an example of a genetic risk factor. The frequencies of factor V Leiden were identical in both control groups, indicating that for the analyses of this genetic risk factor the two control groups could be combined in a single unmatched analysis. In conclusion, the effect measures with the two control groups were in the same direction, and of the same order of magnitude. Moreover, it was not always the same control group that produced the higher or lower estimates, and a matched analysis did not remedy the differences. Our experience with the intricacies of dealing with two control groups may be useful to others when thinking about an optimal research design or the best statistical approach.

Risk factors for hospital acquisition of trimethoprim-sulfamethoxazole resistant Stenotrophomonas maltophilia in adults: A matched case-control study.

PubMed

Wang, Ching-Hsun; Lin, Jung-Chung; Chang, Feng-Yee; Yu, Ching-Mei; Lin, Wei-San; Yeh, Kuo-Ming

2017-10-01

The emergence of trimethoprim-sulfamethoxazole resistant Stenotrophomonas maltophilia (TSRSM) represents a serious threat to patients. The aim of current study was to identify risk factors associated with hospital-acquired TSRSM occurrence in adult inpatients. We conducted a matched case-control study in Tri-Service General Hospital, Taipei, Taiwan. From January 2014 through June 2015, case patients with TSRSM and control patients with trimethoprim-sulfamethoxazole susceptible S. maltophilia (TSSSM) during hospitalization were identified. Control patients were matched with TSRSM cases for age (within five years), sex, and site of isolation at a ratio of 1:1. A total of 266 patients were included in our study (133 cases and 133 matched controls). Bivariable analysis showed that previous exposure to fluoroquinolone [odds ratio (OR), 2.693; 95% confidence interval (CI, 1.492-5.884; p = 0.002)], length of intensive care unit stay (OR, 1.015 per day; 95% CI, 1.001-1.030; p = 0.041), and length of hospital stay (OR, 1.012 per day; 95% CI, 1.002-1.023; p = 0.018) prior to S. maltophilia isolation were associated with TSRSM occurrence. A multivariable analysis showed that previous exposure to fluoroquinolone (OR, 3.158; 95% CI, 1.551-6.430; p = 0.002) was an independent risk factor for TSRSM occurrence after adjustment. Previous fluoroquinolone use was an independent risk factor for hospital-acquired TSRSM occurrence in adult inpatients, suggesting that judicious administration of fluoroquinolone may be important for limiting TSRSM occurrence. Copyright © 2017. Published by Elsevier B.V.

Hyperthyroidism association with SLE, lessons from real-life data--A case-control study.

PubMed

Watad, Abdulla; Cohen, Arnon D; Comaneshter, Doron; Tekes-Manova, Dorit; Amital, Howard

2016-01-01

Despite the frequently encountered association between thyroid disease and systemic lupus erythematosus (SLE) is well known, it is of surprise that only several reports compromised of small population size support this observation. To investigate the association of comorbid SLE and hyperthyroidism. Using the database of the largest health maintenance organization (HMO) in Israel, the Clalit Health Services, we searched for the co-existence of SLE and hyperthyroidism. Patients with SLE were compared with age- and sex-matched controls regarding the prevalence of hyperthyroidism in a case-control study. Chi-square and t-tests were used for univariate analysis and a logistic regression model was used for multivariate analysis. The study included 5018 patients with SLE and 25,090 age- and sex- matched controls. The prevalence of hyperthyroidism in patients with SLE was increased compared with the prevalence in controls (2.59% and 0.91%, respectively, p < 0.001). In a multivariate analysis, SLE was associated with hyperthyroidism (odds ratio 2.52, 95% confidence interval 2.028-3.137). Patients with SLE have a greater prevalence of hyperthyroidism than matched controls. Therefore, physicians treating patients with SLE should be aware of this possibility of this thyroid dysfunction.

Bayesian adjustment for measurement error in continuous exposures in an individually matched case-control study.

PubMed

Espino-Hernandez, Gabriela; Gustafson, Paul; Burstyn, Igor

2011-05-14

In epidemiological studies explanatory variables are frequently subject to measurement error. The aim of this paper is to develop a Bayesian method to correct for measurement error in multiple continuous exposures in individually matched case-control studies. This is a topic that has not been widely investigated. The new method is illustrated using data from an individually matched case-control study of the association between thyroid hormone levels during pregnancy and exposure to perfluorinated acids. The objective of the motivating study was to examine the risk of maternal hypothyroxinemia due to exposure to three perfluorinated acids measured on a continuous scale. Results from the proposed method are compared with those obtained from a naive analysis. Using a Bayesian approach, the developed method considers a classical measurement error model for the exposures, as well as the conditional logistic regression likelihood as the disease model, together with a random-effect exposure model. Proper and diffuse prior distributions are assigned, and results from a quality control experiment are used to estimate the perfluorinated acids' measurement error variability. As a result, posterior distributions and 95% credible intervals of the odds ratios are computed. A sensitivity analysis of method's performance in this particular application with different measurement error variability was performed. The proposed Bayesian method to correct for measurement error is feasible and can be implemented using statistical software. For the study on perfluorinated acids, a comparison of the inferences which are corrected for measurement error to those which ignore it indicates that little adjustment is manifested for the level of measurement error actually exhibited in the exposures. Nevertheless, a sensitivity analysis shows that more substantial adjustments arise if larger measurement errors are assumed. In individually matched case-control studies, the use of conditional logistic regression likelihood as a disease model in the presence of measurement error in multiple continuous exposures can be justified by having a random-effect exposure model. The proposed method can be successfully implemented in WinBUGS to correct individually matched case-control studies for several mismeasured continuous exposures under a classical measurement error model.

Methodological Issues in Design and Analysis of a Matched Case-Control Study of a Vaccine’s Effectiveness

PubMed Central

Niccolai, Linda M.; Ogden, Lorraine G.; Muehlenbein, Catherine E.; Dziura, James D.; Vázquez, Marietta; Shapiro, Eugene D.

2007-01-01

Objective Case-control studies of the effectiveness of a vaccine are useful to answer important questions, such as the effectiveness of a vaccine over time, that usually are not addressed by pre-licensure clinical trials of the vaccine’s efficacy. This report describes methodological issues related to design and analysis that were used to determine the effects of time since vaccination and age at the time of vaccination. Study Design and Setting A matched case-control study of the effectiveness of varicella vaccine. Results Sampling procedures and conditional logistic regression models including interaction terms are described. Conclusion Use of these methods will allow investigators to assess the effects of a wide range of variables, such as time since vaccination and age at the time of vaccination, on the effectiveness of a vaccine. PMID:17938054

Descriptive epidemiology and natural history of idiopathic venous thromboembolism in U.S. active duty enlisted personnel, 1998-2007.

PubMed

Freeman, Randall J; Li, Yuanzhang; Niebuhr, David W

2011-05-01

The estimated incidence of idiopathic venous thromboembolism (IVTE) cases in the United States ranges from 24,000 to 282,000/year. This analysis explores the incidence and prevalence of IVTE in the military and if cases experience increased attrition. The Defense Medical Surveillance System was searched for incident IVTE cases from 1998 through 2007. Enlisted cases were each matched to 3 controls. Kaplan-Meier survival analysis and Cox proportional hazard modeling were performed. We matched 463 cases to 1,389 controls. Outpatient IVTE rates have increased markedly from 1998 through 2007. Cases of all-cause attrition risk (0.56 [95% CI = 0.44, 0.72]) and rates were significantly less than controls (p < 0.0001), and cases of medical attrition risk (1.64 [95% CI = 1.13, 2.37]) and rates were significantly higher (p < 0.01). Increasing rates with lower attrition suggests increasing case prevalence. Health care providers must maintain a high index of suspicion for venous thromboembolism to minimize adverse sequelae affecting health, unit readiness, and medical costs.

Field investigation of influenza vaccine effectiveness on morbidity.

PubMed

Carrat, F; Tachet, A; Rouzioux, C; Housset, B; Valleron, A J

1998-01-01

Our objective was to evaluate influenza vaccine effectiveness during an influenza epidemic by means of a matched case-control study. The study was performed by 35 general practitioners who collected specimens for influenza virus testing from 610 patients who consulted for infectious syndrome: 168 (28%) were influenza-positive. Two designs were used for selecting controls to take into account the high incidence-rate of influenza-like illness and the various possible protective effects of the vaccine. A first disease-free control matched for age and sex was selected during the same week as the case. A second control matched for age and sex was selected at the end of the epidemic period, irrespective of disease history during the epidemic period. Upper and lower bounds of vaccine effectiveness can be derived from these case-control designs. After adjustment for chronic conditions and exposure to an index case, analysis of the matched-pairs whose case was influenza-positive showed, with the first group of controls, an influenza vaccine effectiveness of 68% (95% CI, 10% to 88%) and, in the second group, 53% (95% CI, -19% to 82%). Among the pairs whose case was negative for influenza, vaccine effectiveness was, respectively, 31% (95% CI, -17% to 59%) and 12% (95% CI, -47% to 47%). Vaccine effectiveness was highest for the H3N2 subtype whose vaccine strain was identical to that of the wild-type strain. The results suggest that influenza vaccine is effective in the field in preventing influenza morbidity.

Unconditional or Conditional Logistic Regression Model for Age-Matched Case–Control Data?

PubMed Central

Kuo, Chia-Ling; Duan, Yinghui; Grady, James

2018-01-01

Matching on demographic variables is commonly used in case–control studies to adjust for confounding at the design stage. There is a presumption that matched data need to be analyzed by matched methods. Conditional logistic regression has become a standard for matched case–control data to tackle the sparse data problem. The sparse data problem, however, may not be a concern for loose-matching data when the matching between cases and controls is not unique, and one case can be matched to other controls without substantially changing the association. Data matched on a few demographic variables are clearly loose-matching data, and we hypothesize that unconditional logistic regression is a proper method to perform. To address the hypothesis, we compare unconditional and conditional logistic regression models by precision in estimates and hypothesis testing using simulated matched case–control data. Our results support our hypothesis; however, the unconditional model is not as robust as the conditional model to the matching distortion that the matching process not only makes cases and controls similar for matching variables but also for the exposure status. When the study design involves other complex features or the computational burden is high, matching in loose-matching data can be ignored for negligible loss in testing and estimation if the distributions of matching variables are not extremely different between cases and controls. PMID:29552553

Risk factors for idiopathic intracranial hypertension in men: a case-control study

PubMed Central

Fraser, J. Alexander; Bruce, Beau B.; Rucker, Janet; Fraser, Lisa-Ann; Atkins, Edward J.; Newman, Nancy J.; Biousse, Valérie

2009-01-01

Objective To identify risk factors for idiopathic intracranial hypertension (IIH) in men Design Case-control study. A 96-item telephone questionnaire, answered retrospectively, with cases recalling at the age of their diagnosis and controls recalling at the age of their corresponding case's diagnosis. Setting Outpatient clinics in two US tertiary care centers Participants The characteristics of 24 men with IIH were compared to those of 48 controls matched for sex, age, race, and World Health Organization body mass index (BMI) category. Main Outcome Measures Two previously validated questionnaires: the ADAM (Androgen Deficiency in Aging Males) questionnaire for testosterone deficiency and the Berlin questionnaire for obstructive sleep apnea (OSA), embedded within the telephone questionnaire. Analysis with Mantel-Haenszel odds ratios and mixed-effects logistic regression models accounted for matching. Results Cases and controls had similar enrollment matching characteristics. Although matching was successful by BMI category, there was a small difference between BMI values of cases and controls (cases: median 31.7, controls: median 29.9; p=0.03). After adjustment by BMI value, men with IIH were significantly more likely than controls to have a positive ADAM questionnaire for testosterone deficiency (OR: 17.4, 95% CI: 5.6-54.5; p<0.001) and significantly more likely to have either a positive Berlin questionnaire for OSA or history of diagnosed OSA (OR: 4.4, 95% CI: 1.5-12.9; p=0.03). Conclusions Men with IIH are more likely than controls to have symptoms associated with testosterone deficiency and OSA. These associations suggest a possible role for sex hormones and OSA in the pathogenesis of IIH in men. PMID:19945715

The Impact Of Palifermin Use On Hematopoietic Cell Transplant Outcomes In Children

PubMed Central

Saber, Wael; Zhang, Mei-Jie; Steinert, Patricia; Chen, Min; Horowitz, Mary M

2016-01-01

Purpose Clinical trials evaluating palifermin have enrolled few pediatric patients precluding safety analyses in large groups of children. We compared hematopoietic cell transplant (HCT) outcomes among pediatric patients from a large database who did or did not receive palifermin as a preventive treatment for oral mucositis. Patients and Methods Pediatric patients and controls, matched for HCT and donor type, disease, disease status and age, were selected from the Center for International Blood and Marrow Transplant Research (CIBMTR) database and a 1:3 matched cohort analysis was performed. Stratified Cox proportional hazards models were built and propensity score adjustments were used to compare overall and disease-free survival outcomes between palifermin-treated and untreated patients. Results Three controls were identified for 90% of palifermin recipients. The remaining cases were matched with two (8%) or one (2%) controls, for a total of 210 palifermin-treated patients matched with 606 controls. Median follow-up was 31 months in cases and 36 months in controls. 57% of patients underwent allogeneic HCT, mostly for acute leukemia, and 43% underwent autologous HCT, mostly for solid tumors. In univariate analyses, two-year survival and disease-free survival rates after allogeneic HCT (58% vs 66%, P = .109; 49% vs 60%, P = .060) and after autologous HCT (73% vs 77%, P = .474; 60% vs 64%, P = .637) were similar between palifermin-treated patients and matched controls. In multivariate analysis, palifermin treatment did not significantly increase the risk of mortality (relative risk [RR] 1.20, 95% CI 0.87–1.66) or relapse (RR 1.12, 95% CI 0.78–1.62) compared with matched controls. No significant differences in rates of acute or chronic graft-vs-host disease (GVHD) were observed between palifermin-treated patients and matched controls. Conclusion Among the pediatric patients undergoing HCT, overall survival, disease-free survival, neutrophil recovery, and GVHD rates were similar between palifermin-treated patients and matched controls. PMID:27090960

Optimal case-control matching in practice.

PubMed

Cologne, J B; Shibata, Y

1995-05-01

We illustrate modern matching techniques and discuss practical issues in defining the closeness of matching for retrospective case-control designs (in which the pool of subjects already exists when the study commences). We empirically compare matching on a balancing score, analogous to the propensity score for treated/control matching, with matching on a weighted distance measure. Although both methods in principle produce balance between cases and controls in the marginal distributions of the matching covariates, the weighted distance measure provides better balance in practice because the balancing score can be poorly estimated. We emphasize the use of optimal matching based on efficient network algorithms. An illustration is based on the design of a case-control study of hepatitis B virus infection as a possible confounder and/or effect modifier of radiation-related primary liver cancer in atomic bomb survivors.

Epstein-Barr Virus and Gastric Cancer Risk: A Meta-analysis With Meta-regression of Case-control Studies.

PubMed

Bae, Jong-Myon; Kim, Eun Hee

2016-03-01

Research on how the risk of gastric cancer increases with Epstein-Barr virus (EBV) infection is lacking. In a systematic review that investigated studies published until September 2014, the authors did not calculate the summary odds ratio (SOR) due to heterogeneity across studies. Therefore, we include here additional studies published until October 2015 and conduct a meta-analysis with meta-regression that controls for the heterogeneity among studies. Using the studies selected in the previously published systematic review, we formulated lists of references, cited articles, and related articles provided by PubMed. From the lists, only case-control studies that detected EBV in tissue samples were selected. In order to control for the heterogeneity among studies, subgroup analysis and meta-regression were performed. In the 33 case-control results with adjacent non-cancer tissue, the total number of test samples in the case and control groups was 5280 and 4962, respectively. In the 14 case-control results with normal tissue, the total number of test samples in case and control groups was 1393 and 945, respectively. Upon meta-regression, the type of control tissue was found to be a statistically significant variable with regard to heterogeneity. When the control tissue was normal tissue of healthy individuals, the SOR was 3.41 (95% CI, 1.78 to 6.51; I-squared, 65.5%). The results of the present study support the argument that EBV infection increases the risk of gastric cancer. In the future, age-matched and sex-matched case-control studies should be conducted.

Efficacy of a Self-expanding Tract Sealant Device in the Reduction of Pneumothorax and Chest Tube Placement Rates After Percutaneous Lung Biopsy: A Matched Controlled Study Using Propensity Score Analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ahrar, Judy U., E-mail: judy.ahrar@mdanderson.org; Gupta, Sanjay; Ensor, Joe E.

PurposeTo evaluate the use of a self-expanding tract sealant device (BioSentry™) on the rates of pneumothorax and chest tube insertion after percutaneous lung biopsy.Materials and MethodsIn this retrospective study, we compared 318 patients who received BioSentry™ during percutaneous lung biopsy (treated group) with 1956 patients who did not (control group). Patient-, lesion-, and procedure-specific variables, and pneumothorax and chest tube insertion rates were recorded. To adjust for potential selection bias, patients in the treated group were matched 1:1 to patients in the control group using propensity score matching based on the above-mentioned variables. Patients were considered a match if themore » absolute difference in their propensity scores was ≤equal to 0.02.ResultsBefore matching, the pneumothorax and chest tube rates were 24.5 and 13.1% in the control group, and 21.1 and 8.5% in the treated group, respectively. Using propensity scores, a match was found for 317 patients in the treatment group. Chi-square contingency matched pair analysis showed the treated group had significantly lower pneumothorax (20.8 vs. 32.8%; p = 0.001) and chest tube (8.2 vs. 20.8%; p < 0.0001) rates compared to the control group. Sub-analysis including only faculty who had >30 cases of both treatment and control cases demonstrated similar findings: the treated group had significantly lower pneumothorax (17.6 vs. 30.2%; p = 0.002) and chest tube (7.2 vs. 18%; p = 0.001) rates.ConclusionsThe self-expanding tract sealant device significantly reduced the pneumothorax rate, and more importantly, the chest tube placement rate after percutaneous lung biopsy.« less

Restaurant-associated outbreak of Salmonella typhi in Nauru: an epidemiological and cost analysis.

PubMed Central

Olsen, S. J.; Kafoa, B.; Win, N. S.; Jose, M.; Bibb, W.; Luby, S.; Waidubu, G.; O'Leary, M.; Mintz, E.

2001-01-01

Typhoid fever is endemic in the South Pacific. We investigated an outbreak in Nauru. Through interviews and medical records, we identified 50 persons with onset between 1 October 1998 and 10 May 1999, of fever lasting > or = 3 days and one other symptom. Salmonella Typhi was isolated from 19 (38%) cases. Thirty-two (64%) patients were school-aged children, and 17 (34%) were in four households. Case-control studies of (a) culture-confirmed cases and age- and neighbourhood-matched controls; and (b) household index cases and randomly selected age-matched controls implicated two restaurants: Restaurant M (matched OR [MOR] = 11, 95% confidence interval [CI] = 1.3-96) and Restaurant I (MOR = 5.8, 95% CI = 1.2-29). Food-handlers at both restaurants had elevated anti-Vi antibody titres indicative of carrier state. The annual incidence was 5.0/1000 persons. Outbreak-associated costs were $46,000. Routine or emergency immunization campaigns targeting school-aged children may help prevent or control outbreaks of typhoid fever in endemic disease areas. PMID:11811872

A concordance index for matched case-control studies with applications in cancer risk.

PubMed

Brentnall, Adam R; Cuzick, Jack; Field, John; Duffy, Stephen W

2015-02-10

In unmatched case-control studies, the area under the receiver operating characteristic (ROC) curve (AUC) may be used to measure how well a variable discriminates between cases and controls. The AUC is sometimes used in matched case-control studies by ignoring matching, but it lacks interpretation because it is not based on an estimate of the ROC for the population of interest. We introduce an alternative measure of discrimination that is the concordance of risk factors conditional on the matching factors. Parametric and non-parametric estimators are given for different matching scenarios, and applied to real data from breast and lung cancer case-control studies. Diagnostic plots to verify the constancy of discrimination over matching factors are demonstrated. The proposed simple measure is easy to use, interpret, more efficient than unmatched AUC statistics and may be applied to compare the conditional discrimination performance of risk factors. Copyright © 2014 John Wiley & Sons, Ltd.

The Utility of Case-Control Methods for Health Policy and Planning Analysis: An Illustration from Kinshasa, Zaire.

ERIC Educational Resources Information Center

Mock, Nancy B.; And Others

1993-01-01

The use of case-control methodology as an applied policy/planning research tool in assessing the potential effectiveness of behavioral interventions is studied in connection with diarrhea control in Zaire. Results with 107 matched pairs of children demonstrate the importance of hygiene-related knowledge and the utility of the research approach.…

Is case-chaos methodology an appropriate alternative to conventional case-control studies for investigating outbreaks?

PubMed

Edelstein, Michael; Wallensten, Anders; Kühlmann-Berenzon, Sharon

2014-08-15

Case-chaos methodology is a proposed alternative to case-control studies that simulates controls by randomly reshuffling the exposures of cases. We evaluated the method using data on outbreaks in Sweden. We identified 5 case-control studies from foodborne illness outbreaks that occurred between 2005 and 2012. Using case-chaos methodology, we calculated odds ratios 1,000 times for each exposure. We used the median as the point estimate and the 2.5th and 97.5th percentiles as the confidence interval. We compared case-chaos matched odds ratios with their respective case-control odds ratios in terms of statistical significance. Using Spearman's correlation, we estimated the correlation between matched odds ratios and the proportion of cases exposed to each exposure and quantified the relationship between the 2 using a normal linear mixed model. Each case-control study identified an outbreak vehicle (odds ratios = 4.9-45). Case-chaos methodology identified the outbreak vehicle 3 out of 5 times. It identified significant associations in 22 of 113 exposures that were not associated with outcome and 5 of 18 exposures that were significantly associated with outcome. Log matched odds ratios correlated with their respective proportion of cases exposed (Spearman ρ = 0.91) and increased significantly with the proportion of cases exposed (b = 0.054). Case-chaos methodology missed the outbreak source 2 of 5 times and identified spurious associations between a number of exposures and outcome. Measures of association correlated with the proportion of cases exposed. We recommended against using case-chaos analysis during outbreak investigations. © The Author 2014. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The Impact of Palifermin Use on Hematopoietic Cell Transplant Outcomes in Children.

PubMed

Saber, Wael; Zhang, Mei-Jie; Steinert, Patricia; Chen, Min; Horowitz, Mary M

2016-08-01

Clinical trials evaluating palifermin have enrolled few pediatric patients, precluding safety analyses in large groups of children. We compared hematopoietic cell transplantation (HCT) outcomes among pediatric patients who did or did not receive palifermin as a preventive treatment for oral mucositis. Pediatric patients and controls, matched for HCT and donor type, disease, disease status, and age, were selected from the Center for International Blood and Marrow Transplant Research database and a 1:3 matched cohort analysis was performed. Stratified Cox proportional hazards models were built and propensity score adjustments were used to compare overall and disease-free survival outcomes between palifermin-treated and untreated patients. Three controls were identified for 90% of palifermin recipients. The remaining cases were matched with 2 (8%) controls or 1 (2%) control, for a total of 210 palifermin-treated patients matched with 606 controls. Median follow-up was 31 months in cases and 36 months in controls. Fifty-seven percent of patients underwent allogeneic HCT, mostly for acute leukemia, and 43% underwent autologous HCT, mostly for solid tumors. In univariate analyses, 2-year survival and disease-free survival rates after allogeneic HCT (58% versus 66%, P = .109; 49% versus 60%, P = .06) and after autologous HCT (73% versus 77%, P = .474; 60% versus 64%, P = .637) were similar between palifermin-treated patients and matched controls. In multivariate analysis, palifermin treatment did not significantly increase the risk of mortality (relative risk [RR], 1.20; 95% confidence interval [CI], .87 to 1.66) or of relapse (RR, 1.12; 95% CI, .78 to 1.62) compared with matched controls. No significant differences in rates of acute or chronic graft-versus-host disease (GVHD) were observed between palifermin-treated patients and matched controls. Among pediatric patients undergoing HCT, overall survival, disease-free survival, neutrophil recovery, and GVHD rates were similar between palifermin-treated patients and matched controls. Copyright © 2016 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

A population-based case-control teratologic study of furazidine, a nitrofuran-derivative treatment during pregnancy.

PubMed

Czeizel, A E; Rockenbauer, M; Sørensen, H T; Olsen, J

2000-04-01

To study human teratogenic potential of furazidine treatment during pregnancy. Pair analysis of cases with congenital abnormalities and matched population controls. The Hungarian Case-Control Surveillance of Congenital Abnormalities. 38,151 pregnant women who had newborn infants without any defects (population control group) and 22,865 pregnant women who had newborns or fetuses with congenital abnormalities between 1980 and 1996. In the case group, 157 (0.7%) and in the control group, 254 (0.7%) pregnant women were treated with furazidine. The case-control pair analysis did not indicate a teratogenic potential of furazidine use during the second to third months of gestation, i.e. in the critical period for major congenital abnormalities. Treatment with furazidine during pregnancy did not show teratogenic risk to the fetus.

Combining evidence from multiple electronic health care databases: performances of one-stage and two-stage meta-analysis in matched case-control studies.

PubMed

La Gamba, Fabiola; Corrao, Giovanni; Romio, Silvana; Sturkenboom, Miriam; Trifirò, Gianluca; Schink, Tania; de Ridder, Maria

2017-10-01

Clustering of patients in databases is usually ignored in one-stage meta-analysis of multi-database studies using matched case-control data. The aim of this study was to compare bias and efficiency of such a one-stage meta-analysis with a two-stage meta-analysis. First, we compared the approaches by generating matched case-control data under 5 simulated scenarios, built by varying: (1) the exposure-outcome association; (2) its variability among databases; (3) the confounding strength of one covariate on this association; (4) its variability; and (5) the (heterogeneous) confounding strength of two covariates. Second, we made the same comparison using empirical data from the ARITMO project, a multiple database study investigating the risk of ventricular arrhythmia following the use of medications with arrhythmogenic potential. In our study, we specifically investigated the effect of current use of promethazine. Bias increased for one-stage meta-analysis with increasing (1) between-database variance of exposure effect and (2) heterogeneous confounding generated by two covariates. The efficiency of one-stage meta-analysis was slightly lower than that of two-stage meta-analysis for the majority of investigated scenarios. Based on ARITMO data, there were no evident differences between one-stage (OR = 1.50, CI = [1.08; 2.08]) and two-stage (OR = 1.55, CI = [1.12; 2.16]) approaches. When the effect of interest is heterogeneous, a one-stage meta-analysis ignoring clustering gives biased estimates. Two-stage meta-analysis generates estimates at least as accurate and precise as one-stage meta-analysis. However, in a study using small databases and rare exposures and/or outcomes, a correct one-stage meta-analysis becomes essential. Copyright © 2017 John Wiley & Sons, Ltd.

Cumulative exposure to biologics and risk of cancer in psoriasis patients: A meta-analysis of Psonet studies from Israel, Italy, Spain, United Kingdom and Republic of Ireland.

PubMed

Garcia-Doval, I; Descalzo, M A; Mason, K J; Cohen, A D; Ormerod, A D; Gómez-García, F J; Cazzaniga, S; Feldhamer, I; Ali, H; Herrera-Acosta, E; Griffiths, C E M; Stern, R; Naldi, L

2018-05-03

Cancer risk following long-term exposure to systemic immunomodulatory therapies in psoriasis patients is possible. To assess a dose-response relationship between cumulative length of exposure to biologic therapy and risk of cancer. Four national studies (a healthcare database from Israel, and prospective cohorts form Italy, Spain and UK/ROI) collaborating through Psonet (European Registry of Psoriasis) participated in these nested case-control studies, including nearly 60.000 person-years of observation. Cases were patients who developed an incident cancer. Patients with previous cancers and benign or in-situ tumours were excluded. Four cancer-free controls were matched to each case on year of birth, gender, geographic area, and registration year. Follow-up for controls was censored at the date of cancer diagnosis for the matched case. Conditional logistic regression was performed by each registry. Results were pooled using random effects meta-analysis. 728 cases and 2671 controls were identified. After matching, differences between cases and controls were present for the Charlson comorbidity index in all three registries, and in the prevalence of previous exposure to psoralen-ultraviolet-A (PUVA) and smoking (BADBIR only). The risk of first cancers was not significantly associated with cumulative exposure to biologics (adjusted odds ratio per year of exposure 1.02; 95%CI 0.92, 1.13). Results were similar if squamous and basal cell carcinomas were included in the outcome. Cumulative length of exposure to biologic therapies of psoriasis patients in real-world clinical practice does not appear to be linked to a higher risk of cancer after several years of use. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Long-term survival after traumatic brain injury: a population-based analysis controlled for nonhead trauma.

PubMed

Brown, Allen W; Leibson, Cynthia L; Mandrekar, Jay; Ransom, Jeanine E; Malec, James F

2014-01-01

To examine the contribution of co-occurring nonhead injuries to hazard of death after traumatic brain injury (TBI). A random sample of Olmsted County, Minnesota, residents with confirmed TBI from 1987 through 1999 was identified. Each case was assigned an age- and sex-matched, non-TBI "regular control" from the population. For "special cases" with accompanying nonhead injuries, 2 matched "special controls" with nonhead injuries of similar severity were assigned. Vital status was followed from baseline (ie, injury date for cases, comparable dates for controls) through 2008. Cases were compared first with regular controls and second with regular or special controls, depending on case type. In total, 1257 cases were identified (including 221 special cases). For both cases versus regular controls and cases versus regular or special controls, the hazard ratio was increased from baseline to 6 months (10.82 [2.86-40.89] and 7.13 [3.10-16.39], respectively) and from baseline through study end (2.92 [1.74-4.91] and 1.48 [1.09-2.02], respectively). Among 6-month survivors, the hazard ratio was increased for cases versus regular controls (1.43 [1.06-2.15]) but not for cases versus regular or special controls (1.05 [0.80-1.38]). Among 6-month survivors, accounting for nonhead injuries resulted in a nonsignificant effect of TBI on long-term mortality.

Pernicious anemia and colorectal cancer risk - A nested case-control study.

PubMed

Boursi, Ben; Mamtani, Ronac; Haynes, Kevin; Yang, Yu-Xiao

2016-11-01

Hypergastrinemia was shown to stimulate colonic epithelial cell proliferation. To evaluate the association between pernicious anemia (PA), a disease with hypergastrinemia, and colorectal cancer (CRC) risk. We conducted a nested case-control study within a large database from the UK. Cases were defined as all individuals in the cohort with at least one medical code for CRC. Controls were selected based on incidence-density sampling. For each case, up to four eligible controls were matched on age at diagnosis, sex, practice-site, and both duration and calendar time of follow-up. Exposure of interest was diagnosis of PA prior to CRC diagnosis date. The primary analysis was a multivariable conditional logistic regression. Our study included 22,098 CRC cases and 85,969 matched controls. We identified 154 (0.70%) cases and 563 (0.65%) controls with past history of PA. The adjusted OR for the association between PA and CRC risk was 1.02 (95% CI 0.85-1.22). There was no difference in the results after stratification according to sex. In a sensitivity analysis only among individuals without chronic use of proton pump inhibitors (PPIs) the adjusted OR was 1.14 (95% CI 0.90-1.45). There was no association between duration of PA and CRC risk. PA is not associated with higher CRC risk. Copyright © 2016. Published by Elsevier Ltd.

Specific features of colorectal cancer in patients with metabolic syndrome: a matched case-control analysis of 772 patients.

PubMed

Zarzavadjian Le Bian, Alban; Denet, Christine; Tabchouri, Nicolas; Donatelli, Gianfranco; Wind, Philippe; Louvet, Christophe; Bennamoun, Mostefa; Christidis, Christos; Perniceni, Thierry; Fuks, David; Gayet, Brice

2018-06-01

Although association between colorectal cancer (CRC) and metabolic syndrome (MetS) is established, specific features of CRC arising in patients presenting with MetS have not been clearly identified. All patients who underwent colectomy for CRC from January 2005 to December 2014 at Institut Mutualiste Montsouris were identified from a prospectively collected database and characteristics were compared in the entire population and in a 1:2 matched case-control analysis [variables on which matching was performed were CRC localization (right- or left-sided) and AJCC stage (0 to IV)]. Out of the 772 identified patients, 98 (12.7%) presented with MetS. Entire population analysis revealed that CRC associated with MetS was more frequent in men (71.4 vs. 47.8%, p < 0.001), more often right-sided (71.4 vs. 50.4%, p < 0.001) and presented with less synchronous liver metastasis (4.1 vs. 8.7%, p = 0.002). Case-control analysis confirmed the gender association (p < 0.001) and showed HNPCC (p < 0.001) and history family of CRC (p = 0.010) to be significantly more frequent in Non-MetS patients. CRC associated with MetS is more frequent in men, more often right-sided, and presents with fewer synchronous metastasis. Further investigations should be designed in order to confirm these results and to enhance our knowledge of carcinogenesis related to MetS.

Trivalent inactivated influenza vaccine and spontaneous abortion.

PubMed

Irving, Stephanie A; Kieke, Burney A; Donahue, James G; Mascola, Maria A; Baggs, James; DeStefano, Frank; Cheetham, T Craig; Jackson, Lisa A; Naleway, Allison L; Glanz, Jason M; Nordin, James D; Belongia, Edward A

2013-01-01

To estimate the association between spontaneous abortion and influenza vaccine receipt with a case-control study utilizing data from six health care organizations in the Vaccine Safety Datalink. Women aged 18-44 years with spontaneous abortion during the autumn of 2005 or 2006 were identified using International Classification of Diseases, 9th Revision, Clinical Modification codes. Cases of spontaneous abortion at 5-16 weeks of gestation were confirmed by medical record review; date of fetal demise was based on ultrasound information when available. Control group individuals with a live birth were individually matched to case group individuals by health care organization and date of last menstrual period (LMP). The primary exposure of interest was influenza vaccination during the 28 days preceding the date of spontaneous abortion of the matched pair. Conditional logistic regression models adjusted for maternal age, health care utilization, maternal diabetes, and parity. Our final analysis included 243 women with spontaneous abortion and 243 matched control group women; 82% of women with spontaneous abortion had ultrasound confirmation of fetal demise. Using clinical diagnosis and ultrasound data, the mean gestational age at fetal demise was 7.8 weeks. Mean ages at LMP of case group women and control group women were 31.7 and 29.3 years, respectively (P<.001). Sixteen women with spontaneous abortion (7%) and 15 (6%) matched control group women received influenza vaccine within the 28-day exposure window. There was no association between spontaneous abortion and influenza vaccination in the 28-day exposure window (adjusted matched odds ratio 1.23, 95% confidence interval 0.53-2.89; P=.63). There was no statistically significant increase in the risk of pregnancy loss in the 4 weeks after seasonal inactivated influenza vaccination. II.

Atypical prediagnosis Epstein-Barr virus serology restricted to EBV-positive Hodgkin lymphoma

PubMed Central

Chang, Ellen T.; Ambinder, Richard F.; Lennette, Evelyne T.; Rubertone, Mark V.; Mann, Risa B.; Borowitz, Michael; Weir, Edward G.; Abbondanzo, Susan L.; Mueller, Nancy E.

2012-01-01

An altered anti–Epstein-Barr virus (EBV) serologic profile preceding diagnosis is associated with an increased risk of Hodgkin lymphoma. It is unknown whether this atypical pattern predicts Hodgkin lymphoma risk further subdivided by determination of EBV in tumor cells. A nested case-control study of 128 incident Hodgkin lymphoma cases and 368 matched controls from active-duty military personnel with archived serum in the US Department of Defense Serum Repository was conducted to determine whether a panel of anti-EBV antibody titers differed in EBV+ and EBV− Hodgkin lymphoma. Among 40 EBV+ Hodgkin lymphoma cases and matched controls, statistically significant increased risks were associated with elevated anti-EBV VCA IgG antibody titers (relative risk = 3.1; 95% confidence interval [CI], 1.1-8.7), and an anti–EBNA-1/anti–EBNA-2 antibody ratio ≤ 1.0 versus > 1.0 (relative risk = 4.7; 95% CI, 1.6-13.8). In contrast, no significant associations were found among 88 EBV− Hodgkin lymphoma cases relative to their matched controls. In case-case analysis, EBV+ disease was significantly associated with a low anti–EBNA-1/anti–EBNA-2 antibody ratio. This distinc-tive serologic response to EBV latent antigens, indicative of immune dysfunction in other clinical settings, is associated with an increased risk of developing EBV+ but not EBV− Hodgkin lymphoma. PMID:22972983

Methodologic considerations in the design and analysis of nested case-control studies: association between cytokines and postoperative delirium.

PubMed

Ngo, Long H; Inouye, Sharon K; Jones, Richard N; Travison, Thomas G; Libermann, Towia A; Dillon, Simon T; Kuchel, George A; Vasunilashorn, Sarinnapha M; Alsop, David C; Marcantonio, Edward R

2017-06-06

The nested case-control study (NCC) design within a prospective cohort study is used when outcome data are available for all subjects, but the exposure of interest has not been collected, and is difficult or prohibitively expensive to obtain for all subjects. A NCC analysis with good matching procedures yields estimates that are as efficient and unbiased as estimates from the full cohort study. We present methodological considerations in a matched NCC design and analysis, which include the choice of match algorithms, analysis methods to evaluate the association of exposures of interest with outcomes, and consideration of overmatching. Matched, NCC design within a longitudinal observational prospective cohort study in the setting of two academic hospitals. Study participants are patients aged over 70 years who underwent scheduled major non-cardiac surgery. The primary outcome was postoperative delirium from in-hospital interviews and medical record review. The main exposure was IL-6 concentration (pg/ml) from blood sampled at three time points before delirium occurred. We used nonparametric signed ranked test to test for the median of the paired differences. We used conditional logistic regression to model the risk of IL-6 on delirium incidence. Simulation was used to generate a sample of cohort data on which unconditional multivariable logistic regression was used, and the results were compared to those of the conditional logistic regression. Partial R-square was used to assess the level of overmatching. We found that the optimal match algorithm yielded more matched pairs than the greedy algorithm. The choice of analytic strategy-whether to consider measured cytokine levels as the predictor or outcome-- yielded inferences that have different clinical interpretations but similar levels of statistical significance. Estimation results from NCC design using conditional logistic regression, and from simulated cohort design using unconditional logistic regression, were similar. We found minimal evidence for overmatching. Using a matched NCC approach introduces methodological challenges into the study design and data analysis. Nonetheless, with careful selection of the match algorithm, match factors, and analysis methods, this design is cost effective and, for our study, yields estimates that are similar to those from a prospective cohort study design.

Lack of association between migraine headache and patent foramen ovale: results of a case-control study.

PubMed

Garg, Pallav; Servoss, Stephen J; Wu, Justina C; Bajwa, Zahid H; Selim, Magdy H; Dineen, Alexis; Kuntz, Richard E; Cook, E Francis; Mauri, Laura

2010-03-30

Clinical observations of migraine headache symptoms in patients with a patent foramen ovale (PFO), both of which conditions are highly prevalent, have raised the question of a possible pathophysiological relationship. We sought to evaluate the assumption of an association between migraine headaches and the presence of PFO by use of a large case-control study. We conducted a case-control study to assess the prevalence of PFO in subjects with and without migraine. Case subjects were those with a history of migraine (diagnosed by neurologists at a specialty academic headache clinic). Control subjects were healthy volunteers without migraine 1:1 matched on the basis of age and sex with case subjects. Presence of PFO was determined by transthoracic echocardiogram with second harmonic imaging and transcranial Doppler ultrasonography during a standardized procedure of infused agitated saline contrast with or without Valsalva maneuver and a review of the results by experts blinded to case-control status. PFO was considered present if both studies were positive. Odds ratios were calculated with conditional logistic regression in the matched cohort (n=288). In the matched analysis, the prevalence of PFO was similar in case and control subjects (26.4% versus 25.7%; odds ratio 1.04, 95% confidence interval 0.62 to 1.74, P=0.90). There was no difference in PFO prevalence in those with migraine with aura and those without (26.8% versus 26.1%; odds ratio 1.03, 95% confidence interval 0.48 to 2.21, P=0.93). We found no association between migraine headaches and the presence of PFO in this large case-control study.

Propensity score matching for selection of local areas as controls for evaluation of effects of alcohol policies in case series and quasi case-control designs.

PubMed

de Vocht, F; Campbell, R; Brennan, A; Mooney, J; Angus, C; Hickman, M

2016-03-01

Area-level public health interventions can be difficult to evaluate using natural experiments. We describe the use of propensity score matching (PSM) to select control local authority areas (LAU) to evaluate the public health impact of alcohol policies for (1) prospective evaluation of alcohol policies using area-level data, and (2) a novel two-stage quasi case-control design. Ecological. Alcohol-related indicator data (Local Alcohol Profiles for England, PHE Health Profiles and ONS data) were linked at LAU level. Six LAUs (Blackpool, Bradford, Bristol, Ipswich, Islington, and Newcastle-upon-Tyne) as sample intervention or case areas were matched to two control LAUs each using PSM. For the quasi case-control study a second stage was added aimed at obtaining maximum contrast in outcomes based on propensity scores. Matching was evaluated based on average standardized absolute mean differences (ASAM) and variable-specific P-values after matching. The six LAUs were matched to suitable control areas (with ASAM < 0.20, P-values >0.05 indicating good matching) for a prospective evaluation study that sought areas that were similar at baseline in order to assess whether a change in intervention exposure led to a change in the outcome (alcohol related harm). PSM also generated appropriate matches for a quasi case-control study--whereby the contrast in health outcomes between cases and control areas needed to be optimized in order to assess retrospectively whether differences in intervention exposure were associated with the outcome. The use of PSM for area-level alcohol policy evaluation, but also for other public health interventions, will improve the value of these evaluations by objective and quantitative selection of the most appropriate control areas. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Proton pump inhibitor use and recurrent Clostridium difficile-associated disease: a case-control analysis matched by propensity score.

PubMed

Kim, Yong Gil; Graham, David Y; Jang, Byung Ik

2012-01-01

Clostridium difficile has been increasingly diagnosed in hospitalized patients. An association between proton pump inhibitors (PPIs) use and Clostridium difficile-associated disease (CDAD) and between recurrent CDAD has been suggested. The aim of this study is to investigate whether PPI use is associated with the development of recurrent CDAD. This was a retrospective case-control study of patients with CDAD at Yeungnam University Medical Center, seen from January 2004 to December 2008. C. difficile infection was diagnosed by the presence of C. difficile toxin in the stool. Those with recurrent disease were matched with nonrecurrent controls using multivariate matched sampling methods that incorporated the propensity score. Recurrent CDAD developed in 28 (14.1%) of the 198 patients with diarrhea and positive C. difficile stool toxin assays. Multivariate analysis of the total population of recurrent versus nonrecurrent CDAD revealed that additional use of non-C. difficile antimicrobial therapy (concomitant with the treatment or after or both), poor response to therapy with metronidazole or vancomycin, and recent gastrointestinal surgery were risk factors for recurrent CDAD. We were able to match 21 recurrent CDAD subjects with 21 without recurrent CDAD. Among the matched patients only PPI use was associated with recurrent CDAD (ie, 47.6% vs. 4.8%, P=0.004 for recurrent vs. nonrecurrent CDAD, respectively). Among the matched patient groups, only PPI therapy was associated with recurrent CDAD. Prospective studies are needed to clarify whether avoidance of PPIs or specific cotherapies will reduce the incidence of recurrent C. difficile-associated diarrhea.

Risk factors for late onset gram-negative infections: a case-control study.

PubMed

Samanta, Srabani; Farrer, Kate; Breathnach, Aodhan; Heath, Paul T

2011-01-01

To determine the incidence, mortality and risk factors for neonatal late onset gram-negative sepsis and meningitis (LOGNS). Retrospective case-control study. Tertiary neonatal unit in London. Consecutive inborn infants with late onset (>48 h of life) invasive gram-negative infections diagnosed between 1999 and 2005. Controls were healthy infants matched for gestation and time of admission to the neonatal unit. Clinical and risk factor data. 73 cases of LOGNS were identified of which 48 were inborn and included in the study (incidence 1.85/1000 live births). Enterobacter spp. (28%), Escherichia coli (27%) and Klebsiella spp. (21%) were the most common pathogens. The majority of infants were of very low birthweight (VLBW; 79%), and cases and controls were well matched (median gestation 26 weeks). Overall case death was 27% in cases versus 13.5% in controls (p=0.08). There was no significant difference between cases and controls regarding maternal risk factors. Mechanical ventilation, total parenteral nutrition (TPN) and its duration, presence of a central venous line and its duration, use of specific antibiotics and the occurrence of necrotising enterocolitis at or before the first positive culture were all significantly associated with case status in univariate analysis. In multivariate logistic regression analysis, only duration of TPN at or before first positive blood culture remained independently associated with LOGNS (p<0.001). LOGNS occurs predominantly in VLBW infants. When the influence of gestational age is accounted for, the only independent risk factor found for late onset gram-negative neonatal infections is the duration of TPN.

Piped water supply interruptions and acute diarrhea among under-five children in Addis Ababa slums, Ethiopia: A matched case-control study.

PubMed

Adane, Metadel; Mengistie, Bezatu; Medhin, Girmay; Kloos, Helmut; Mulat, Worku

2017-01-01

The problem of intermittent piped water supplies that exists in low- and middle-income countries is particularly severe in the slums of sub-Saharan Africa. However, little is known about whether there is deterioration of the microbiological quality of the intermittent piped water supply at a household level and whether it is a factor in reducing or increasing the occurrence of acute diarrhea among under-five children in slums of Addis Ababa. This study aimed to determine the association of intermittent piped water supplies and point-of-use (POU) contamination of household stored water by Escherichia coli (E. coli) with acute diarrhea among under-five children in slums of Addis Ababa. A community-based matched case-control study was conducted from November to December, 2014. Cases were defined as under-five children with acute diarrhea during the two weeks before the survey. Controls were matched by age and neighborhood with cases by individual matching. Data were collected using a pre-tested structured questionnaire and E. coli analysis of water from piped water supplies and household stored water. A five-tube method of Most Probable Number (MPN)/100 ml standard procedure was used for E. coli analysis. Multivariable conditional logistic regression with 95% confidence interval (CI) was used for data analysis by controlling potential confounding effects of selected socio-demographic characteristics. During the two weeks before the survey, 87.9% of case households and 51.0% of control households had an intermittent piped water supply for an average of 4.3 days and 3.9 days, respectively. POU contamination of household stored water by E. coli was found in 83.3% of the case households, and 52.1% of the control households. In a fully adjusted model, a periodically intermittent piped water supply (adjusted matched odds ratio (adjusted mOR) = 4.8; 95% CI: 1.3-17.8), POU water contamination in household stored water by E. coli (adjusted mOR = 3.3; 95% CI: 1.1-10.1), water retrieved from water storage containers using handle-less vessels (adjusted mOR = 16.3; 95% CI: 4.4-60.1), and water retrieved by interchangeably using vessels both with and without handle (adjusted mOR = 5.4; 95% CI: 1.1-29.1) were independently associated with acute diarrhea. We conclude that provision of continuously available piped water supplies and education of caregivers about proper water retrieval methods of household stored water can effectively reduce POU contamination of water at the household level and thereby reduce acute diarrhea among under-five children in slums of Addis Ababa. Promotion of household water treatment is also highly encouraged until the City's water authority is able to deliver continuously available piped water supplies.

Transanal pullthrough for Hirschsprung disease: matched case-control comparison of Soave and Swenson techniques.

PubMed

Nasr, Ahmed; Haricharan, Ramanath N; Gamarnik, Julie; Langer, Jacob C

2014-05-01

Both the Swenson and the Soave procedures have been adapted to a transanal approach. The purpose of this study was to compare outcomes following the transanal Swenson and Soave procedures using a matched case control analysis. A retrospective chart review was performed to identify all transanal Soave and Swenson pullthroughs done at 2 tertiary care children's hospitals between 2000 and 2010. Patients were matched for gestational age, mean weight at time of the operation, level of aganglionosis, and presence of co-morbidities. Student's t-test and chi-squared analysis were performed. Fifty-four patients (Soave 27, Swenson 27) had adequate data for matching and analysis. Mean follow-up was 4±1.6 years and 3.2 ±2.7 years for the Soave and Swenson groups, respectively. No significant differences in mean operating time (Soave:191±55, Swenson:167±61 min, p=0.6), overall hospital stay (6±4 vs 7.8±5 days, p=0.7), and number with intra-operative complications (3 vs 4, p=1.0), post-operative obstructive symptoms (6 vs 9, p=0.5), enterocolitis episodes (4 vs 4, p=1.0), or fecal incontinence (0 vs 2, p=0.4) were noted. After controlling for potential confounders, there were no significant differences in the short and intermediate term outcome between transanal Soave and transanal Swenson pullthrough procedures. Copyright © 2014 Elsevier Inc. All rights reserved.

Applying Matched Sampling to Evaluate a University Tutoring Program for First-Year Students

ERIC Educational Resources Information Center

Walvoord, Mark E.; Pleitz, Jacob D.

2016-01-01

Our study used a case-control matching design to assess the influence of a voluntary tutoring program in improving first-year students' Grade Point Averages (GPA). To evaluate program effectiveness, we applied case-control matching to obtain 215 pairs of students with or without participation in tutoring, but matched on high school GPA and…

Association between age and high-risk human papilloma virus in Mexican oral cancer patients.

PubMed

González-Ramírez, I; Irigoyen-Camacho, M E; Ramírez-Amador, V; Lizano-Soberón, M; Carrillo-García, A; García-Carrancá, A; Sánchez-Pérez, Y; Méndez-Martínez, R; Granados-García, M; Ruíz-Godoy, Lm; García-Cuellar, Cm

2013-11-01

Studies reporting low prevalence of HPV in OSCC with declining age at presentation are increasing. The aim of this study was to determine the prevalence of HPV in a group of OSCC cases and controls in a Mexican population. The matched case-control study included 80 OSCC cases and 320 controls. HPV/DNA presence was evaluated through PCR amplification using three sets of consensus primers for the L1 gene. A conditional logistic regression analysis was carried out for the matched OSCC cases and controls. Interactions between risk factors and OCSS were tested in the construction process of the models. HPV prevalence was 5% in OSCC cases and 2.5% in controls. HPV-detected types were 16, 18 and 56. According to conditional logistics regression model, an association was detected between HR-HPV and OSCC. All HR-HPV-positive OSCC cases corresponded to young patients (<45 years), non-smokers and non-alcohol drinkers. The HR-HPV can be a contributing factor to oral carcinogenesis, especially in younger individuals without known risk factors such as tobacco and alcohol. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Incidental Prophylactic Nodal Irradiation and Patterns of Nodal Relapse in Inoperable Early Stage NSCLC Patients Treated With SBRT: A Case-Matched Analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lao, Louis; Department of Radiation Oncology, Auckland City Hospital, Auckland; Hope, Andrew J.

2014-09-01

Purpose: Reported rates of non-small cell lung cancer (NSCLC) nodal failure following stereotactic body radiation therapy (SBRT) are lower than those reported in the surgical series when matched for stage. We hypothesized that this effect was due to incidental prophylactic nodal irradiation. Methods and Materials: A prospectively collected group of medically inoperable early stage NSCLC patients from 2004 to 2010 was used to identify cases with nodal relapses. Controls were matched to cases, 2:1, controlling for tumor volume (ie, same or greater) and tumor location (ie, same lobe). Reference (normalized to equivalent dose for 2-Gy fractions [EQD2]) point doses atmore » the ipsilateral hilum and carina, demographic data, and clinical outcomes were extracted from the medical records. Univariate conditional logistical regression analyses were performed with variables of interest. Results: Cases and controls were well matched except for size. The controls, as expected, had larger gross tumor volumes (P=.02). The mean ipsilateral hilar doses were 9.6 Gy and 22.4 Gy for cases and controls, respectively (P=.014). The mean carinal doses were 7.0 Gy and 9.2 Gy, respectively (P=.13). Mediastinal nodal relapses, with and without ipsilateral hilar relapse, were associated with mean ipsilateral hilar doses of 3.6 Gy and 19.8 Gy, respectively (P=.01). The conditional density plot appears to demonstrate an inverse dose-effect relationship between ipsilateral hilar normalized total dose and risk of ipsilateral hilar relapse. Conclusions: Incidental hilar dose greater than 20 Gy is significantly associated with fewer ipsilateral hilar relapses in inoperable early stage NSCLC patients treated with SBRT.« less

On the use and misuse of scalar scores of confounders in design and analysis of observational studies.

PubMed

Pfeiffer, R M; Riedl, R

2015-08-15

We assess the asymptotic bias of estimates of exposure effects conditional on covariates when summary scores of confounders, instead of the confounders themselves, are used to analyze observational data. First, we study regression models for cohort data that are adjusted for summary scores. Second, we derive the asymptotic bias for case-control studies when cases and controls are matched on a summary score, and then analyzed either using conditional logistic regression or by unconditional logistic regression adjusted for the summary score. Two scores, the propensity score (PS) and the disease risk score (DRS) are studied in detail. For cohort analysis, when regression models are adjusted for the PS, the estimated conditional treatment effect is unbiased only for linear models, or at the null for non-linear models. Adjustment of cohort data for DRS yields unbiased estimates only for linear regression; all other estimates of exposure effects are biased. Matching cases and controls on DRS and analyzing them using conditional logistic regression yields unbiased estimates of exposure effect, whereas adjusting for the DRS in unconditional logistic regression yields biased estimates, even under the null hypothesis of no association. Matching cases and controls on the PS yield unbiased estimates only under the null for both conditional and unconditional logistic regression, adjusted for the PS. We study the bias for various confounding scenarios and compare our asymptotic results with those from simulations with limited sample sizes. To create realistic correlations among multiple confounders, we also based simulations on a real dataset. Copyright © 2015 John Wiley & Sons, Ltd.

Common mental disorders associated with tuberculosis: a matched case-control study.

PubMed

de Araújo, Gleide Santos; Pereira, Susan Martins; dos Santos, Darci Neves; Marinho, Jamocyr Moura; Rodrigues, Laura Cunha; Barreto, Mauricio Lima

2014-01-01

Despite the availability of treatment and a vaccine, tuberculosis continues to be a public health problem worldwide. Mental disorders might contribute to the burden of the disease. The objective of this study was to investigate the association between common mental disorders and tuberculosis. A matched case-control study was conducted. The study population included symptomatic respiratory patients who attended three referral hospitals and six community clinics in the city of Salvador, Brazil. A doctor's diagnosis defined potential cases and controls. Cases were newly diagnosed tuberculosis cases, and controls were symptomatic respiratory patients for whom tuberculosis was excluded as a diagnosis by the attending physician. Cases and controls were ascertained in the same clinic. Data collection occurred between August 2008 and April 2010. The study instruments included a structured interview, a self-reporting questionnaire for the identification of common mental disorders, and a questionnaire for alcoholism. An univariate analysis included descriptive procedures (with chi-square statistics), and a multivariate analysis used conditional logistic regression. The mean age of the cases was 38 years, and 61% of the cases were males. After adjusting for potential confounders, the odds of tuberculosis were significantly higher in patients diagnosed with a common mental disorder (OR: 1.34; 95% CI 1.05-1.70). There appears to be a positive and independent association between common mental disorders and tuberculosis; further epidemiological studies are required to increase our understanding of the possible biological and social mechanisms responsible for this association. Independent of the direction of the association, this finding has implications for the provision of care for mental disorders and for tuberculosis.

[Application of nested case-control study on safe evaluation of post-marketing traditional Chinese medicine injection].

PubMed

Xiao, Ying; Zhao, Yubin; Xie, Yanming

2011-10-01

The nested case-control study design (or the case-control in a cohort study) is described here as a new study design used in safe evaluation of post-marketing traditional Chinese medicine injection. In the nested case-control study, cases of a disease that occur in a defined cohort are identified and, for each, a specified number of matched controls is selected from among those in the cohort who have not developed the disease by the time of disease occurrence in the case. For many research questions, the nested case-control design potentially offers impressive reductions in costs and efforts of data collection and analysis compared with the full cohort approach, with relatively minor loss in statistical efficiency. The nested case-control design is particularly advantageous for studies in safe evaluation of post-marketing traditional Chinese medicine injection. Some examples of the application of nested case-control study were given.

Visits on 'lamb-viewing days' at a sheep farm open to the public was a risk factor for Q fever in 2009.

PubMed

Whelan, J; Schimmer, B; de Bruin, A; van Beest Holle, M Robert-du Ry; van der Hoek, W; ter Schegget, R

2012-05-01

Between February and May 2009, 347 laboratory-confirmed cases of acute Q fever were reported in a southern municipal health service region in The Netherlands. Commercial dairy-goat farms were implicated and control measures were initially targeted there. A preliminary investigation also implicated a non-dairy sheep farm, open to the public on 'lamb-viewing days'. This study tested the association between visiting the non-dairy sheep farm and developing Q fever in residents of the region between February and May 2009. A case-control study of 146 cases and 431 address-matched controls was conducted. Multivariable logistic regression analysis confirmed the association between visiting to the sheep farm and Q fever disease (matched odds ratio 43, 95% confidence interval 9-200). Other risk factors were being a smoker, having a past medical history and being aged >40 years. Vaccination of sheep and goats on farms open to the public should help to reduce the number of future human cases.

Antidepressant Use After Aneurysmal Subarachnoid Hemorrhage: A Population-Based Case-Control Study.

PubMed

Huttunen, Jukka; Lindgren, Antti; Kurki, Mitja I; Huttunen, Terhi; Frösen, Juhana; von Und Zu Fraunberg, Mikael; Koivisto, Timo; Kälviäinen, Reetta; Räikkönen, Katri; Viinamäki, Heimo; Jääskeläinen, Juha E; Immonen, Arto

2016-09-01

To elucidate the predictors of antidepressant use after subarachnoid hemorrhage from saccular intracranial aneurysm (sIA-SAH) in a population-based cohort with matched controls. The Kuopio sIA database includes all unruptured and ruptured sIA cases admitted to the Kuopio University Hospital from its defined catchment population in Eastern Finland, with 3 matched controls for each patient. The use of all prescribed medicines has been fused from the Finnish national registry of prescribed medicines. In the present study, 2 or more purchases of antidepressant medication indicated antidepressant use. The risk factors of the antidepressant use were analyzed in 940 patients alive 12 months after sIA-SAH, and the classification tree analysis was used to create a predicting model for antidepressant use after sIA-SAH. The 940 12-month survivors of sIA-SAH had significantly more antidepressant use (odds ratio, 2.6; 95% confidence interval, 2.2-3.1) than their 2676 matched controls (29% versus 14%). Classification tree analysis, based on independent risk factors, was used for the best prediction model of antidepressant use after sIA-SAH. Modified Rankin Scale until 12 months was the most potent predictor, followed by condition (Hunt and Hess Scale) and age on admission for sIA-SAH. The sIA-SAH survivors use significantly more often antidepressants, indicative of depression, than their matched population controls. Even with a seemingly good recovery (modified Rankin Scale score, 0) at 12 months after sIA-SAH, there is a significant risk of depression requiring antidepressant medication. © 2016 American Heart Association, Inc.

Budget Impact Analysis of Veterans Affairs Medical Foster Homes versus Community Living Centers.

PubMed

Sutton, Bryce S; Pracht, Étienne; Williams, Arthur R; Alemi, Farrokh; Williams, Allison E; Levy, Cari

2017-02-01

The objectives were to determine whether and by what amounts the US Department of Veterans Affairs (VA) use of Medical Foster Homes (MFH) rather than Community Living Centers (CLC) reduced budget impacts to the VA. This was a retrospective, matched, case-control study of veterans residing in MFH or CLC in the VA health care system from 2008 to 2012. Administrative data sets, nearest neighbor matching, generalized linear models, and a secondary analysis were used to capture and analyze budget impacts by veterans who used MFH or CLC exclusively in 2008-2012. Controls of 1483 veterans in CLC were matched to 203 cases of veterans in MFH. Use of MFH instead of CLC reduced budget impacts to the VA by at least $2645 per veteran per month. A secondary analysis of the data using different matching criteria and statistical methods produced similar results, demonstrating the robustness of the estimates of budget impact. When the average out-of-pocket payments made by MFH residents, not made by CLC residents, were included in the analysis, the net reduction of budget impact ranged from $145 to $2814 per veteran per month or a savings of $1740 to $33,768 per veteran per year. Even though outpatient costs of MFH are higher, much of the reduced budget impact of MFH use arises from lower inpatient or hospital costs. Reduced budget impacts on the VA system indicate that expansion of the MFH program may be cost-effective. Implications for further research are suggested.

Assessing different measures of population-level vaccine protection using a case-control study.

PubMed

Ali, Mohammad; You, Young Ae; Kanungo, Suman; Manna, Byomkesh; Deen, Jacqueline L; Lopez, Anna Lena; Wierzba, Thomas F; Bhattacharya, Sujit K; Sur, Dipika; Clemens, John D

2015-11-27

Case-control studies have not been examined for their utility in assessing population-level vaccine protection in individually randomized trials. We used the data of a randomized, placebo-controlled trial of a cholera vaccine to compare the results of case-control analyses with those of cohort analyses. Cases of cholera were selected from the trial population followed for three years following dosing. For each case, we selected 4 age-matched controls who had not developed cholera. For each case and control, GIS was used to calculate vaccine coverage of individuals in a surrounding "virtual" cluster. Specific selection strategies were used to evaluate the vaccine protective effects. 66,900 out of 108,389 individuals received two doses of the assigned regimen. For direct protection among subjects in low vaccine coverage clusters, we observed 78% (95% CI: 47-91%) protection in a cohort analysis and 84% (95% CI: 60-94%) in case-control analysis after adjusting for confounding factors. Using our GIS-based approach, estimated indirect protection was 52% (95% CI: 10-74%) in cohort and 76% (95% CI: 47-89%) in case control analysis. Estimates of total and overall effectiveness were similar for cohort and case-control analyses. The findings show that case-control analyses of individually randomized vaccine trials may be used to evaluate direct as well as population-level vaccine protection. Copyright © 2015. Published by Elsevier Ltd.

Biomarker discovery study design for type 1 diabetes in The Environmental Determinants of Diabetes in the Young (TEDDY) study.

PubMed

Lee, Hye-Seung; Burkhardt, Brant R; McLeod, Wendy; Smith, Susan; Eberhard, Chris; Lynch, Kristian; Hadley, David; Rewers, Marian; Simell, Olli; She, Jin-Xiong; Hagopian, Bill; Lernmark, Ake; Akolkar, Beena; Ziegler, Anette G; Krischer, Jeffrey P

2014-07-01

The Environmental Determinants of Diabetes in the Young planned biomarker discovery studies on longitudinal samples for persistent confirmed islet cell autoantibodies and type 1 diabetes using dietary biomarkers, metabolomics, microbiome/viral metagenomics and gene expression. This article describes the details of planning The Environmental Determinants of Diabetes in the Young biomarker discovery studies using a nested case-control design that was chosen as an alternative to the full cohort analysis. In the frame of a nested case-control design, it guides the choice of matching factors, selection of controls, preparation of external quality control samples and reduction of batch effects along with proper sample allocation. Our design is to reduce potential bias and retain study power while reducing the costs by limiting the numbers of samples requiring laboratory analyses. It also covers two primary end points (the occurrence of diabetes-related autoantibodies and the diagnosis of type 1 diabetes). The resulting list of case-control matched samples for each laboratory was augmented with external quality control samples. Copyright © 2013 John Wiley & Sons, Ltd.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lea, C.S.; Selvin, S.; Buffler, P.A.

This pilot study uses a unique method to calculate cumulative lifetime exposure to, ultraviolet radiation-b to determine if this refined method would indicate differences in lifetime cumulative UVB exposure between age and sex matched controls. Forty-four age and sex matched cases and controls demonstrated no significant difference in mean cumulative lifetime UVB exposure based on the duration and location of residence. This pilot study suggests that further analysis of the dataset should be conducted to determine if the cumulative lifetime exposure hypothesis is of primary importance regarding the association between UVB exposure and development of cutaneous malignant melanoma.

Mitochondrial dysfunction in Gulf War illness revealed by 31Phosphorus Magnetic Resonance Spectroscopy: a case-control study.

PubMed

Koslik, Hayley J; Hamilton, Gavin; Golomb, Beatrice A

2014-01-01

Approximately 1/3 of 1990-1 Gulf War veterans developed chronic multisymptom health problems. Implicated exposures bear mechanisms that adversely affect mitochondria. Symptoms emphasize fatigue, cognition and muscle (brain and muscle are aerobically demanding); with protean additional domains affected, compatible with mitochondrial impairment. Recent evidence supports treatments targeting cell bioenergetics (coenzyme10) to benefit Gulf War illness symptoms. However, no evidence has directly documented mitochondrial or bioenergetic impairment in Gulf War illness. We sought to objectively assess for mitochondrial dysfunction, examining post-exercise phosphocreatine-recovery time constant (PCr-R) using (31)Phosphorus Magnetic Resonance Spectroscopy ((31)P-MRS), in Gulf War veterans with Gulf War illness compared to matched healthy controls. PCr-R has been described as a "robust and practical" index of mitochondrial status. Case-control study from 2012-2013. Fourteen community-dwelling Gulf War veterans and matched controls from the San Diego area comprised 7 men meeting CDC and Kansas criteria for Gulf War illness, and 7 non-deployed healthy controls matched 1:1 to cases on age, sex, and ethnicity. Calf muscle phosphocreatine was evaluated by (31)P-MRS at rest, through 5 minutes of foot pedal depression exercise, and in recovery, to assess PCr-R. Paired t-tests compared cases to matched controls. PCr-R was significantly prolonged in Gulf War illness cases vs their matched controls: control values, mean ± SD, 29.0 ± 8.7 seconds; case values 46.1 ± 18.0 seconds; difference 17.1 ± 14.9 seconds; p = 0.023. PCr-R was longer for cases relative to their matched controls for all but one pair; moreover while values clustered under 31 seconds for all but one control, they exceeded 35 seconds (with a spread up to 70 seconds) for all but one case. These data provide the first direct evidence supporting mitochondrial dysfunction in Gulf War illness. Findings merit replication in a larger study and/or corroboration with additional mitochondrial assessment tools.

rhBMP-2 protects against reoperation for pseudoarthrosis and/or instrumentation failure: A matched case-control study of 448 patients.

PubMed

Macki, Mohamed; Syeda, Sbaa; Kerezoudis, Panagiotis; Bydon, Ali; Witham, Timothy F; Sciubba, Daniel M; Wolinsky, Jean-Paul; Bydon, Mohamad; Gokaslan, Ziya

2016-10-01

The objective of this independent study is to determine the impact of recombinant human bone morphogenetic protein 2 (rhBMP-2) on reoperation for pseudarthrosis and/or instrumentation failure. A nested case-control study of first-time posterolateral, instrumented fusion of the lumbar spine for degenerative spinal disease was undertaken. Cases of reoperation for pseudoarthrosis and/or instrumentation failure were assigned to controls, who did not experience the primary outcome measure at the time of reoperation. Cases and controls were matched on number of interspaces fused and inclusion of interbody. Predictors of reoperation for pseudoarthrosis and/or instrumentation failure were assessed with a conditional logistical regression controlling for rhBMP-2, age, obesity, and smoking. Of the 448 patients, 155 cases of reoperation for pseudoarthrosis and/or instrumentation were matched with 293 controls. Twenty-six percent of first-time surgeries included rhBMP-2, which was statistically more commonly used in the control cohort (33.11%) versus the case cohort (12.90%) (Unadjusted odds ratio [ORunadj]=0.28) (95% confidence interval [CI]: 0.16-0.49). Following a multivariate analysis controlling for age, obesity, and smoking, the rhBMP-2 recipients incurred a 73% lower odds of reoperation for pseudoarthrosis and/or instrumentation failure (95% CI, 0.15-0.48). Neither sarcomatous nor osseous neoplasm was detected in the study population. Mean follow up did not differ between the cases (81.57±standard deviation [SD] 4.98months) versus controls (74.75±2.49month) (ORunadj=1.01) (95% CI: 1.00-1.01). rhBMP-2 in lumbar fusion constructs protects against reoperation for pseudoarthrosis and/or instrumentation failure. However, the decision to include fusion supplements should be weighted between surgical determinants and clinical outcomes. Copyright © 2016 Elsevier Ltd. All rights reserved.

An Algorithm for Creating Virtual Controls Using Integrated and Harmonized Longitudinal Data.

PubMed

Hansen, William B; Chen, Shyh-Huei; Saldana, Santiago; Ip, Edward H

2018-06-01

We introduce a strategy for creating virtual control groups-cases generated through computer algorithms that, when aggregated, may serve as experimental comparators where live controls are difficult to recruit, such as when programs are widely disseminated and randomization is not feasible. We integrated and harmonized data from eight archived longitudinal adolescent-focused data sets spanning the decades from 1980 to 2010. Collectively, these studies examined numerous psychosocial variables and assessed past 30-day alcohol, cigarette, and marijuana use. Additional treatment and control group data from two archived randomized control trials were used to test the virtual control algorithm. Both randomized controlled trials (RCTs) assessed intentions, normative beliefs, and values as well as past 30-day alcohol, cigarette, and marijuana use. We developed an algorithm that used percentile scores from the integrated data set to create age- and gender-specific latent psychosocial scores. The algorithm matched treatment case observed psychosocial scores at pretest to create a virtual control case that figuratively "matured" based on age-related changes, holding the virtual case's percentile constant. Virtual controls matched treatment case occurrence, eliminating differential attrition as a threat to validity. Virtual case substance use was estimated from the virtual case's latent psychosocial score using logistic regression coefficients derived from analyzing the treatment group. Averaging across virtual cases created group estimates of prevalence. Two criteria were established to evaluate the adequacy of virtual control cases: (1) virtual control group pretest drug prevalence rates should match those of the treatment group and (2) virtual control group patterns of drug prevalence over time should match live controls. The algorithm successfully matched pretest prevalence for both RCTs. Increases in prevalence were observed, although there were discrepancies between live and virtual control outcomes. This study provides an initial framework for creating virtual controls using a step-by-step procedure that can now be revised and validated using other prevention trial data.

Evaluation of Female Breast Cancer Risk Among the Betel Quid Chewer: A Bio-Statistical Assessment in Assam, India.

PubMed

Rajbongshi, Nijara; Mahanta, Lipi B; Nath, Dilip C

2015-06-01

Breast cancer is the most commonly diagnosed cancer among the female population of Assam, India. Chewing of betel quid with or without tobacco is common practice among female population of this region. Moreoverthe method of preparing the betel quid is different from other parts of the country.So matched case control study is conducted to analyse whetherbetel quid chewing plays a significant role in the high incidence of breast cancer occurrences in Assam. Here, controls are matched to the cases by age at diagnosis (±5 years), family income and place of residence with matching ratio 1:1. Conditional logistic regression models and odd ratios (OR) was used to draw conclusions. It is observed that cases are more habituated to chewing habits than the controls.Further the conditional logistic regression analysis reveals that betel quid chewer faces 2.353 times more risk having breast cancer than the non-chewer with p value 0.0003 (95% CI 1.334-4.150). Though the female population in Assam usually does not smoke, the addictive habits typical to this region have equal effect on the occurrence of breast cancer.

Generalisability of vaccine effectiveness estimates: an analysis of cases included in a postlicensure evaluation of 13-valent pneumococcal conjugate vaccine in the USA

PubMed Central

Link-Gelles, Ruth; Westreich, Daniel; Aiello, Allison E; Shang, Nong; Weber, David J; Rosen, Jennifer B; Motala, Tasneem; Mascola, Laurene; Eason, Jeffery; Scherzinger, Karen; Holtzman, Corinne; Reingold, Arthur L; Barnes, Meghan; Petit, Susan; Farley, Monica M; Harrison, Lee H; Zansky, Shelley; Thomas, Ann; Schaffner, William; McGee, Lesley; Whitney, Cynthia G; Moore, Matthew R

2017-01-01

Objectives External validity, or generalisability, is the measure of how well results from a study pertain to individuals in the target population. We assessed generalisability, with respect to socioeconomic status, of estimates from a matched case–control study of 13-valent pneumococcal conjugate vaccine effectiveness for the prevention of invasive pneumococcal disease in children in the USA. Design Matched case–control study. Setting Thirteen active surveillance sites for invasive pneumococcal disease in the USA. Participants Cases were identified from active surveillance and controls were age and zip code matched. Outcome measures Socioeconomic status was assessed at the individual level via parent interview (for enrolled individuals only) and birth certificate data (for both enrolled and unenrolled individuals) and at the neighbourhood level by geocoding to the census tract (for both enrolled and unenrolled individuals). Prediction models were used to determine if socioeconomic status was associated with enrolment. Results We enrolled 54.6% of 1211 eligible cases and found a trend toward enrolled cases being more affluent than unenrolled cases. Enrolled cases were slightly more likely to have private insurance at birth (p=0.08) and have mothers with at least some college education (p<0.01). Enrolled cases also tended to come from more affluent census tracts. Despite these differences, our best predictive model for enrolment yielded a concordance statistic of only 0.703, indicating mediocre predictive value. Variables retained in the final model were assessed for effect measure modification, and none were found to be significant modifiers of vaccine effectiveness. Conclusions We conclude that although enrolled cases are somewhat more affluent than unenrolled cases, our estimates are externally valid with respect to socioeconomic status. Our analysis provides evidence that this study design can yield valid estimates and the assessing generalisability of observational data is feasible, even when unenrolled individuals cannot be contacted. PMID:28851801

Piped water supply interruptions and acute diarrhea among under-five children in Addis Ababa slums, Ethiopia: A matched case-control study

PubMed Central

Adane, Metadel; Mengistie, Bezatu; Medhin, Girmay; Kloos, Helmut; Mulat, Worku

2017-01-01

Background The problem of intermittent piped water supplies that exists in low- and middle-income countries is particularly severe in the slums of sub-Saharan Africa. However, little is known about whether there is deterioration of the microbiological quality of the intermittent piped water supply at a household level and whether it is a factor in reducing or increasing the occurrence of acute diarrhea among under-five children in slums of Addis Ababa. This study aimed to determine the association of intermittent piped water supplies and point-of-use (POU) contamination of household stored water by Escherichia coli (E. coli) with acute diarrhea among under-five children in slums of Addis Ababa. Methods A community-based matched case-control study was conducted from November to December, 2014. Cases were defined as under-five children with acute diarrhea during the two weeks before the survey. Controls were matched by age and neighborhood with cases by individual matching. Data were collected using a pre-tested structured questionnaire and E. coli analysis of water from piped water supplies and household stored water. A five-tube method of Most Probable Number (MPN)/100 ml standard procedure was used for E. coli analysis. Multivariable conditional logistic regression with 95% confidence interval (CI) was used for data analysis by controlling potential confounding effects of selected socio-demographic characteristics. Main findings During the two weeks before the survey, 87.9% of case households and 51.0% of control households had an intermittent piped water supply for an average of 4.3 days and 3.9 days, respectively. POU contamination of household stored water by E. coli was found in 83.3% of the case households, and 52.1% of the control households. In a fully adjusted model, a periodically intermittent piped water supply (adjusted matched odds ratio (adjusted mOR) = 4.8; 95% CI: 1.3–17.8), POU water contamination in household stored water by E. coli (adjusted mOR = 3.3; 95% CI: 1.1–10.1), water retrieved from water storage containers using handle-less vessels (adjusted mOR = 16.3; 95% CI: 4.4–60.1), and water retrieved by interchangeably using vessels both with and without handle (adjusted mOR = 5.4; 95% CI: 1.1–29.1) were independently associated with acute diarrhea. Conclusion We conclude that provision of continuously available piped water supplies and education of caregivers about proper water retrieval methods of household stored water can effectively reduce POU contamination of water at the household level and thereby reduce acute diarrhea among under-five children in slums of Addis Ababa. Promotion of household water treatment is also highly encouraged until the City’s water authority is able to deliver continuously available piped water supplies. PMID:28723927

Comparisons of serum miRNA expression profiles in patients with diabetic retinopathy and type 2 diabetes mellitus.

PubMed

Ma, Jianping; Wang, Jufang; Liu, Yanfen; Wang, Changyi; Duan, Donghui; Lu, Nanjia; Wang, Kaiyue; Zhang, Lu; Gu, Kaibo; Chen, Sihan; Zhang, Tao; You, Dingyun; Han, Liyuan

2017-02-01

The aim of this study was to compare the expression levels of serum miRNAs in diabetic retinopathy and type 2 diabetes mellitus. Serum miRNA expression profiles from diabetic retinopathy cases (type 2 diabetes mellitus patients with diabetic retinopathy) and type 2 diabetes mellitus controls (type 2 diabetes mellitus patients without diabetic retinopathy) were examined by miRNA-specific microarray analysis. Quantitative real-time polymerase chain reaction was used to validate the significantly differentially expressed serum miRNAs from the microarray analysis of 45 diabetic retinopathy cases and 45 age-, sex-, body mass index- and duration-of-diabetes-matched type 2 diabetes mellitus controls. The relative changes in serum miRNA expression levels were analyzed using the 2-ΔΔCt method. A total of 5 diabetic retinopathy cases and 5 type 2 diabetes mellitus controls were included in the miRNA-specific microarray analysis. The serum levels of miR-3939 and miR-1910-3p differed significantly between the two groups in the screening stage; however, quantitative real-time polymerase chain reaction did not reveal significant differences in miRNA expression for 45 diabetic retinopathy cases and their matched type 2 diabetes mellitus controls. Our findings indicate that miR-3939 and miR-1910-3p may not play important roles in the development of diabetic retinopathy; however, studies with a larger sample size are needed to confirm our findings.

Risk of radiation-induced malignancy with heterotopic ossification prophylaxis: a case-control analysis.

PubMed

Sheybani, Arshin; TenNapel, Mindi J; Lack, William D; Clerkin, Patrick; Hyer, Daniel E; Sun, Wenqing; Jacobson, Geraldine M

2014-07-01

To determine the risk of radiation-induced malignancy after prophylactic treatment for heterotopic ossification (HO). A matched case-control study was conducted within a population-based cohort of 3489 patients treated either for acetabular fractures with acetabular open reduction internal fixation or who underwent total hip arthroplasty from 1990 to 2009. Record-linkage techniques identified patients who were diagnosed with a malignancy from our state health registry. Patients with a prior history of malignancy were excluded from the cohort. For each documented case of cancer, 2 controls were selected by stratified random sampling from the cohort that did not develop a malignancy. Matching factors were sex, age at time of hip treatment, and duration of follow-up. A total of 243 patients were diagnosed with a malignancy after hip treatment. Five patients were excluded owing to inadequate follow-up time in the corresponding control cohort. A cohort of 238 cases (control, 476 patients) was included. Mean follow-up was 10 years, 12 years in the control group. In the cancer cohort, 4% of patients had radiation therapy (RT), compared with 7% in the control group. Of the 9 patients diagnosed with cancer after RT, none occurred within the field. The mean latency period was 5.9 years in the patients who received RT and 6.6 years in the patients who did not. Median (range) age at time of cancer diagnosis in patients who received RT was 62 (43-75) years, compared with 70 (32-92) years in the non-RT patients. An ad hoc analysis was subsequently performed in all 2749 patients who were not matched and found neither an increased incidence of malignancy nor a difference in distribution of type of malignancy. We were unable to demonstrate an increased risk of malignancy in patients who were treated with RT for HO prophylaxis compared with those who were not. Copyright © 2014 Elsevier Inc. All rights reserved.

A Step-by-Step Guide to Propensity Score Matching in R

ERIC Educational Resources Information Center

Randolph, Justus J.; Falbe, Kristina; Manuel, Austin Kureethara; Balloun, Joseph L.

2014-01-01

Propensity score matching is a statistical technique in which a treatment case is matched with one or more control cases based on each case's propensity score. This matching can help strengthen causal arguments in quasi-experimental and observational studies by reducing selection bias. In this article we concentrate on how to conduct propensity…

A prospective study of Trichomonas vaginalis and prostate cancer risk among African American men.

PubMed

Fowke, Jay H; Han, Xijing; Alderete, J F; Moses, Kelvin A; Signorello, Lisa B; Blot, William J

2016-04-18

African Americans (AA) have a higher prevalence of Trichomonas vaginalis (Tv) infection and a higher prostate (PC) risk. Past studies suggest an association between Tv seropositivity and PC, and therefore we prospectively investigated this association among AA men. Incident PC cases were individually matched to controls in a nested case-control study within the Southern Community Cohort Study (SCCS). Primary analysis included 296 PC cases and 497 race-matched controls. Levels of Tv antibody response were measured by ELISA in serum collected at baseline. Tv antibody response did not significantly differ between cases and controls overall or within AA participants (253 AA cases). There were no significant associations or trends between levels of Tv response and PC risk or the diagnosis of aggressive PC. We found no evidence of a prospective association between baseline Tv infection and PC risk in AA men. Tv infection in men may have substantial health implications in HIV transmission and reproductive outcomes, but may not impact future PC risk in AA men at high-risk for PC. Further efforts need to define past vs. present Tv infection and to separate pathophysiology from PC detection.

Investigation to identify a resource-efficient case-control methodology for determining antibiotics associated with Clostridium difficile infection.

PubMed

Chung, Philip; Currie, Brian; Guo, Yi; Talansky, Moshe; Brown, Shakara; Ostrowsky, Belinda

2014-10-01

Antimicrobial exposure remains an important risk factor for developing Clostridium difficile infection (CDI). Efficient method to identify antibiotics associated with CDI is important for formulating strategies to curtail their use. As a prelude to a more extensive Agency for Healthcare Research and Quality-funded project (Evaluation & Research on Antimicrobial Stewardship's Effect on Clostridium difficile), we undertook an exploratory evaluation to determine a resource-efficient method for identifying antibiotic targets for antimicrobial stewardship interventions. The study compared a series of 6 focused case-control studies. Cases consisted of patients with laboratory-confirmed CDI admitted from July-October 2009. Controls were selected from patients without CDI hospitalized during the same period. Five groups of controls were matched to cases (2:1 ratio) using group-specific matching criteria, including admission date, age, type of admission, length of stay (LOS) to discharge, and/or LOS to CDI diagnosis. The final control group was selected from patients who received antibiotics during hospitalization. Data, including demographics and antibiotic usage, were compared between case and control groups. A total of 126 cases were matched to 6 groups of 252 controls. For control groups 1-5, the use of piperacillin and tazobactam, ceftriaxone or cefepime, ciprofloxacin or moxifloxacin, intravenous vancomycin, azithromycin, and antibiotics of last resort were significantly more frequent in case than control patients. For the final control group, the associations between ceftriaxone or cefepime, and ciprofloxacin or moxifloxacin use and CDI no longer persisted. This could in part be explained by differences in comorbidities between case and control patients even with stringent matching criteria. Use of a simple matching strategy to conduct case-control studies is an efficient and feasible compromise strategy, especially in resource-limited settings, to identify high-risk antibiotics associated with CDI. Copyright © 2014 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

VIM-positive Pseudomonas aeruginosa in a large tertiary care hospital: matched case-control studies and a network analysis.

PubMed

Voor In 't Holt, Anne F; Severin, Juliëtte A; Hagenaars, Margot B H; de Goeij, Inge; Gommers, Diederik; Vos, Margreet C

2018-01-01

Emergence of multidrug-resistant Pseudomonas aeruginosa is of global concern. We aimed to identify epidemiological relationships, the most common way of transmission, and risk factors for presence of Verona Integron-encoded Metallo-β-lactamase (VIM)-positive P. aeruginosa (VIM-PA). We conducted a network analysis and matched case-control studies (1:2:2). Controls were hospital-based and matched with cases for ward, day of admission (control group 1 and 2) and time between admission and the identification of VIM-PA (control group 1). The network was visualized using Cytoscape, and risk factors were determined using conditional logistic regression. Between August 2003 and April 2015, 144 case patients and 576 control patients were recruited. We identified 307 relationships in 114 out of these 144 patients, with most relationships (84.7%) identified at the same department < 3 months after a previous case patient was discharged. In the multivariable model, having undergone ≥1 gastroscopy (odds ratio [OR] = 4.40, 95% confidence interval [CI] = 2.00 to 9.65 and OR = 2.47; 95% CI = 1.12 to 5.49), > 10 day use of selective digestive tract decontamination (SDD) (OR = 2.97; 95% CI = 1.02 to 8.68 and OR = 4.61; 95% CI = 1.22 to 17.37), and use of quinolones (OR = 3.29; 95% CI = 1.34 to 8.10 and OR = 3.95; 95% CI = 1.13 to 13.83 and OR = 4.47; 95% CI = 1.75 to 11.43) were identified as risk factors when using both control groups. The network analysis indicated that the majority of transmissions occurred on the wards, but through unidentified and presumably persistent sources, which are most likely in the innate hospital environment. Previous use of certain antibiotic regimens made patients prone to VIM-PA carriage. Additionally, gastroscopy could be considered as a high-risk procedure in patients with risk factors. Our results add to the growing body of evidence that infection control measures targeting VIM-PA should be focused on reducing antibiotics and eliminating sources in the environment.

The association of contact lens solution use and Acanthamoeba keratitis

PubMed Central

Joslin, Charlotte E.; Tu, Elmer Y.; Shoff, Megan E.; Booton, Gregory C.; Fuerst, Paul A.; McMahon, Timothy T.; Anderson, Robert J.; Dworkin, Mark S.; Sugar, Joel; Davis, Faith G.; Stayner, Leslie T.

2009-01-01

Purpose Diagnosis of Acanthamoeba keratitis, a rare but serious corneal infection, has recently increased significantly at the University of Illinois at Chicago (UIC) Cornea Service. The purpose is to investigate Acanthamoeba keratitis risk factors. Design Retrospective case-control study. Methods Setting University, tertiary care hospital. Patients Fifty-five Acanthamoeba keratitis cases with contact lens use were diagnosed between May 1, 2003 and September 15, 2006. Clinic-matched controls with contact lens use were recruited. Subjects completed surveys targeting lens hygiene, contact lens solution use, and water exposure. Main Outcome Measure Acanthamoeba keratitis. Results Thirty-nine (73.6%) cases and 113 (65.3%) controls participated; 38 cases had complete contact lens data. Thirty-five of 38 cases (92.1%) and 47 of 100 controls (47.0%) used soft lenses. Analysis was performed on 30 cases and 39 controls with matched pairs with soft lens use. Exclusive use of AMO Complete MoisturePlus Multi-Purpose Solution was independently associated with Acanthamoeba keratitis in multivariable analysis (55.2% vs. 10.5%; OR, 16.67; 95% CI, 2.11–162.63; p = 0.008). However, 38.8% of cases reported no use of AMO Complete MoisturePlus Multi-Purpose Solution or used it in combination with other solutions. Although not statistically significant, additional hygiene-related variables (solution ‘reuse’, lack of ‘rubbing’, and showering with lenses) suggest a pattern of risk,. Conclusions AMO Complete MoisturePlus Multi-Purpose Solution use is independently associated with Acanthamoeba keratitis among soft contact lens users. However, it does not explain all cases, suggesting additional factors. Further research into environmental risk factors and hygiene practices is warranted, especially considering this is the second outbreak of an atypical, contact lens-related infection. PMID:17588524

The association of contact lens solution use and Acanthamoeba keratitis.

PubMed

Joslin, Charlotte E; Tu, Elmer Y; Shoff, Megan E; Booton, Gregory C; Fuerst, Paul A; McMahon, Timothy T; Anderson, Robert J; Dworkin, Mark S; Sugar, Joel; Davis, Faith G; Stayner, Leslie T

2007-08-01

To investigate Acanthamoeba keratitis (AK) risk factors. Diagnosis of AK, a rare but serious corneal infection, has recently increased significantly at the University of Illinois at Chicago (UIC) Cornea Service. Retrospective case-control study. settings: University, tertiary care hospital. patients: Fifty-five AK cases with contact lens use were diagnosed between May 1, 2003 and September 15, 2006. Clinic-matched controls with contact lens use were recruited. Subjects completed surveys targeting lens hygiene, contact lens solution use, and water exposure. main outcome measure: Acanthamoeba keratitis. Thirty-nine (73.6%) cases and 113 (65.3%) controls participated; 38 cases had complete contact lens data. Thirty-five of 38 cases (92.1%) and 47 of 100 controls (47.0%) used soft lenses. Analysis was performed on 30 cases and 39 controls with matched pairs with soft lens use. Exclusive use of Advance Medical Optics (AMO) Complete MoisturePlus Multi-Purpose Solution was independently associated with AK in multivariable analysis (55.2% vs 10.5%; odds ratio [OR], 16.67; 95% confidence interval [CI] 2.11 to 162.63; P = .008). However, 38.8% of cases reported no use of AMO Complete MoisturePlus Multi-Purpose Solution either alone or in combination with other solutions. Although not statistically significant, additional hygiene-related variables (solution "reuse," lack of "rubbing," and showering with lenses) suggest a pattern of risk. AMO Complete MoisturePlus Multi-Purpose Solution use is independently associated with AK among soft contact lens users. However, it does not explain all cases, suggesting additional factors. Further research into environmental risk factors and hygiene practices is warranted, especially considering this is the second outbreak of an atypical, contact lens-related infection.

Effectiveness of 7-valent pneumococcal conjugate vaccine in the prevention of invasive pneumococcal disease in children aged 7-59 months. A matched case-control study.

PubMed

Domínguez, Angela; Ciruela, Pilar; García-García, Juan José; Moraga, Fernando; de Sevilla, Mariona F; Selva, Laura; Coll, Francis; Muñoz-Almagro, Carmen; Planes, Ana María; Codina, Gemma; Jordán, Iolanda; Esteva, Cristina; Hernández, Sergi; Soldevila, Núria; Cardeñosa, Neus; Batalla, Joan; Salleras, Luis

2011-11-08

The aim of this study was to evaluate the effectiveness of the administration of the 7-valent pneumococcal conjugate vaccine in a region with an intermediate vaccination coverage. A matched case-control study was carried out in children aged 7-59 months with invasive pneumococcal disease (IPD) admitted to two university hospitals in Catalonia. Three controls matched for hospital, age, sex, date of hospitalization and underlying disease were selected for each case. Information on the vaccination status of cases and controls was obtained from the vaccination card, the child's health card, the hospital medical record or the vaccination register of the primary healthcare center where the child was attended for non-severe conditions. A conditional logistic regression analysis was made to control for the effect of possible confounding variables. The adjusted vaccination effectiveness of the complete vaccination schedule (3 doses at 2, 4 and 6 months and a fourth dose at 15 months, 2 doses at least two months apart in children aged 12-23 months or a single dose in children aged >24 months) in preventing IPD caused by vaccine serotypes was 93.7% (95% CI 51.8-99.2). It was not effective in preventing cases caused by non-vaccine serotypes. The results of this study carried out in a population with intermediate vaccination coverage confirm those of other observational studies showing high levels of effectiveness of routine 7-valent pneumococcal conjugate vaccination. Copyright © 2011 Elsevier Ltd. All rights reserved.

Gall bladder mucoceles and their association with endocrinopathies in dogs: a retrospective case-control study.

PubMed

Mesich, M L L; Mayhew, P D; Paek, M; Holt, D E; Brown, D C

2009-12-01

To investigate the relationship between endocrinopathies and diagnosis of gall bladder mucocele in dogs via a retrospective case-control study. Records of 78 dogs with a surgical or ultrasonographic diagnosis of gall bladder mucocele were examined for the presence or absence of hyperadrenocorticism, hypothyroidism and diabetes mellitus. Two age- and breed-matched controls for each gall bladder mucocele dog (156 total control dogs) were examined for the same concurrent diseases. A matched case-control analysis was performed using conditional logistic regression. The odds of mucocele in dogs with hyperadrenocorticism were 29 times that of dogs without hyperadrenocorticism (P=0.001; 95 per cent CI 3.8, 219.9). No difference was found between dogs with and without diabetes mellitus. Although a significant association was found between gall bladder mucocele and hypothyroidism, potential observation bias was also identifi ed. Hyperadrenocorticoid dogs that were presented for acute illness with laboratory evidence of hepatobiliary disease should undergo evaluation for the presence of a biliary mucocele. Dogs diagnosed with a gall bladder mucocele should be screened for concurrent hyperadrenocorticism if clinical suspicion exists.

Excess Readmission vs Excess Penalties: Maximum Readmission Penalties as a Function of Socioeconomics and Geography.

PubMed

Caracciolo, Chris; Parker, Devin; Marshall, Emily; Brown, Jeremiah

2017-08-01

The Hospital Readmission Reduction Program (HRRP) penalizes hospitals with "excess" readmissions up to 3% of Medicare reimbursement. Approximately 75% of eligible hospitals received penalties, worth an estimated $428 million, in fiscal year 2015. To identify demographic and socioeconomic disparities between matched and localized maximum-penalty and no-penalty hospitals. A case-control study in which cases included were hospitals to receive the maximum 3% penalty under the HRRP during the 2015 fiscal year. Controls were drawn from no-penalty hospitals and matched to cases by hospital characteristics (primary analysis) or geographic proximity (secondary analysis). A selectiion of 3383 US hospitals eligible for HRRP. Thirty-nine case and 39 control hospitals from the HRRP cohort. Socioeconomic status variables were collected by the American Community Survey. Hospital and health system characteristics were drawn from Centers for Medicare and Medicaid Services, American Hospital Association, and Dartmouth Atlas of Health Care. The statistical analysis was conducted using Student t tests. Thirty-nine hospitals received a maximum penalty. Relative to controls, maximum-penalty hospitals in counties with lower SES profiles are defined by increased poverty rates (19.1% vs 15.5%, = 0.015) and lower rates of high school graduation (82.2% vs 87.5%, = 0.001). County level age, sex, and ethnicity distributions were similar between cohorts. Cases were more likely than controls to be in counties with low socioeconomic status; highlighting potential unintended consequences of national benchmarks for phenomena underpinned by environmental factors; specifically, whether maximum penalties under the HRRP are a consequence of underperforming hospitals or a manifestation of underserved communities. © 2017 Society of Hospital Medicine

Endemic cryptosporidiosis and exposure to municipal tap water in persons with acquired immunodeficiency syndrome (AIDS): A case-control study

PubMed Central

Aragón, Tomás J; Novotny, Suzanne; Enanoria, Wayne; Vugia, Duc J; Khalakdina, Asheena; Katz, Mitchell H

2003-01-01

Background In persons with acquired immunodeficiency syndrome (AIDS), Cryptosporidium parvum causes a prolonged, severe diarrheal illness to which there is no effective treatment, and the risk of developing cryptosporidiosis from drinking tap water in non-outbreak settings remains uncertain. To test the hypothesis that drinking tap water was associated with developing cryptosporidiosis, we conducted a matched case-control study among persons with AIDS in San Francisco. Methods Among patients reported to the San Francisco AIDS Registry from May 1996 through September 1998, we compared patients who developed cryptosporidiosis to those who did not. Cases were individually matched to controls based on age, sex, race/ethnicity, CD4+ T lymphocyte count, date of CD4+ count, and date of case diagnosis. Population attributable fractions (PAFs) were calculated. Results The study consisted of 49 cases and 99 matched controls. In the multivariable analysis with adjustments for confounders, tap water consumption inside and outside the home at the highest exposure categories was associated with the occurrence of cryptosporidiosis (inside the home: odds ratio (OR), 6.76; 95% CI 1.37–33.5, and outside the home: OR 3.16; 95% CI 1.23–8.13). The PAF was 85%; that is, the proportion of cases of cryptosporidiosis in San Francisco AIDS patients attributable to tap water consumption could have been as high as 85%. Conclusions Although the results from this observational study cannot be considered definitive, until there is more data, we recommend persons with AIDS, especially those with compromised immune systems, consider avoiding tap water. PMID:12515584

Endemic cryptosporidiosis and exposure to municipal tap water in persons with acquired immunodeficiency syndrome (AIDS): a case-control study.

PubMed

Aragón, Tomás J; Novotny, Suzanne; Enanoria, Wayne; Vugia, Duc J; Khalakdina, Asheena; Katz, Mitchell H

2003-01-06

In persons with acquired immunodeficiency syndrome (AIDS), Cryptosporidium parvum causes a prolonged, severe diarrheal illness to which there is no effective treatment, and the risk of developing cryptosporidiosis from drinking tap water in non-outbreak settings remains uncertain. To test the hypothesis that drinking tap water was associated with developing cryptosporidiosis, we conducted a matched case-control study among persons with AIDS in San Francisco. Among patients reported to the San Francisco AIDS Registry from May 1996 through September 1998, we compared patients who developed cryptosporidiosis to those who did not. Cases were individually matched to controls based on age, sex, race/ethnicity, CD4+ T lymphocyte count, date of CD4+ count, and date of case diagnosis. Population attributable fractions (PAFs) were calculated. The study consisted of 49 cases and 99 matched controls. In the multivariable analysis with adjustments for confounders, tap water consumption inside and outside the home at the highest exposure categories was associated with the occurrence of cryptosporidiosis (inside the home: odds ratio (OR), 6.76; 95% CI 1.37-33.5, and outside the home: OR 3.16; 95% CI 1.23-8.13). The PAF was 85%; that is, the proportion of cases of cryptosporidiosis in San Francisco AIDS patients attributable to tap water consumption could have been as high as 85%. Although the results from this observational study cannot be considered definitive, until there is more data, we recommend persons with AIDS, especially those with compromised immune systems, consider avoiding tap water.

Ring-enhancement pattern on contrast-enhanced CT predicts adenosquamous carcinoma of the pancreas: a matched case-control study.

PubMed

Imaoka, Hiroshi; Shimizu, Yasuhiro; Mizuno, Nobumasa; Hara, Kazuo; Hijioka, Susumu; Tajika, Masahiro; Tanaka, Tsutomu; Ishihara, Makoto; Ogura, Takeshi; Obayashi, Tomohiko; Shinagawa, Akihide; Sakaguchi, Masafumi; Yamaura, Hidekazu; Kato, Mina; Niwa, Yasumasa; Yamao, Kenji

2014-01-01

Adenosquamous carcinoma of the pancreas (ASC) is a rare malignant neoplasm of the pancreas, exhibiting both glandular and squamous differentiation. However, little is known about its imaging features. This study examined the imaging features of pancreatic ASC. We evaluated images of contrast-enhanced computed tomography (CT) and endoscopic ultrasonography (EUS). As controls, solid pancreatic neoplasms matched in a 2:1 ratio to ASC cases for age, sex and tumor location were also evaluated. Twenty-three ASC cases were examined, and 46 solid pancreatic neoplasms (43 pancreatic ductal adenocarcinomas, two pancreatic neuroendocrine tumors and one acinar cell carcinoma) were matched as controls. Univariate analysis demonstrated significant differences in the outline and vascularity of tumors on contrast-enhanced CT in the ASC and control groups (P < 0.001 and P < 0.001, respectively). A smooth outline, cystic changes, and the ring-enhancement pattern on contrast-enhanced CT were seen to have significant predictive powers by stepwise forward logistic regression analysis (P = 0.044, P = 0.010, and P = 0.001, respectively). Of the three, the ring-enhancement pattern was the most useful, and its predictive diagnostic sensitivity, specificity, positive predictive value and negative predictive value for diagnosis of ASC were 65.2%, 89.6%, 75.0% and 84.3%, respectively. These results demonstrate that presence of the ring-enhancement pattern on contrast-enhanced CT is the most useful predictive factor for ASC. Copyright © 2014 IAP and EPC. Published by Elsevier B.V. All rights reserved.

Vaccination history and risk of childhood leukaemia.

PubMed

Ma, Xiaomei; Does, Monique B; Metayer, Catherine; Russo, Carolyn; Wong, Alan; Buffler, Patricia A

2005-10-01

Previous studies on vaccination and childhood leukaemia generated inconsistent results. In the Northern California Childhood Leukaemia Study, a case-control study with incident cases and matched birth certificate controls, detailed written vaccination records were collected. A total of 323 cases aged 0-14 years at diagnosis and 409 controls were included in this analysis. All vaccinations were censored on the reference date (date of diagnosis for cases and the corresponding date for matched controls). Conditional logistic regression analysis was conducted, adjusting for potential confounding factors. A primary variable of interest is the number of administrations (doses) of various types of vaccines. Vaccinations against diphtheria, pertussis, tetanus, poliomyelitis, measles, mumps, and rubella were not associated with the risk of leukaemia. The odds ratio for each dose of Haemophilus influenzae type b (Hib) vaccine was 0.81 (95% CI 0.68-0.96). Compared with children who received two or fewer doses of Hib vaccine, those who received three or more doses had a significantly reduced risk of childhood leukaemia (odds ratio = 0.55, 95% confidence interval 0.32-0.94). The number of doses of hepatitis B vaccine received was not associated with leukaemia risk. Hib vaccination is associated with a reduced risk of childhood leukaemia. Future studies with detailed exposure assessment and large sample sizes are needed to further address the role of vaccinations in the etiology of childhood leukaemia.

Maternal Exposure to Bisphenol-A and Fetal Growth Restriction: A Case-Referent Study

PubMed Central

Burstyn, Igor; Martin, Jonathan W.; Beesoon, Sanjay; Bamforth, Fiona; Li, Qiaozhi; Yasui, Yutaka; Cherry, Nicola M.

2013-01-01

We conducted a case-referent study of the effect of exposure to bisphenol-A on fetal growth in utero in full-term, live-born singletons in Alberta, Canada. Newborns <10 percentile of expected weight for gestational age and sex were individually matched on sex, maternal smoking and maternal age to referents with weight appropriate to gestational age. Exposure of the fetus to bisphenol-A was estimated from maternal serum collected at 15–16 weeks of gestation. We pooled sera across subjects for exposure assessment, stratified on case-referent status and sex. Individual 1:1 matching was maintained in assembling 69 case and 69 referent pools created from 550 case-referent pairs. Matched pools had an equal number of aliquots from individual women. We used an analytical strategy conditioning on matched set and total pool-level values of covariates to estimate individual-level effects. Pools of cases and referents had identical geometric mean bisphenol-A concentrations (0.5 ng/mL) and similar geometric standard deviations (2.3–2.5). Mean difference in concentration between matched pools was 0 ng/mL, standard deviation: 1 ng/mL. Stratification by sex and control for confounding did not suggest bisphenol-A increased fetal growth restriction. Our analysis does not provide evidence to support the hypothesis that bisphenol-A contributes to fetal growth restriction in full-term singletons. PMID:24336026

Dietary habits after myocardial infarction - results from a cross-sectional study.

PubMed

Wallström, P; Mattisson, I; Tydén, P; Berglund, G; Janzon, L

2005-04-01

Comparing habitual nutrient intakes in persons with a history of acute myocardial infarction (AMI), and age-matched controls. Design. Cross-sectional study. Subjects. Men and women (525 cases and 1890 matched controls), aged 47-73 years, of the population-based Malmö Diet and Cancer cohort. Nutrient intakes were assessed by a validated modified diet history method. Body fatness was assessed by bioimpedance analysis. Case ascertainment was provided by national and regional registries. Men and women were analysed separately. Median time since AMI was 5.5 years in men and 3.8 years in women. Cases reported lower energy intakes (EIs) than controls, despite having similar basal metabolic rates. After adjustment for total EI, both male and female cases had lower fat intake and higher intake of several micronutrients, such as ascorbic acid, folate, and vitamin E, than controls, the difference being largest in men. Most of the cases reporting dietary change quoted 'disease' as their main reason for change. They had lower EI and lower energy-adjusted intake of fat than other cases. Survivors of AMI reported dietary habits more in line with current recommendations, particularly those who afterwards reported having changed their dietary habits. The possible bias introduced by social desirability is discussed.

Estimating time-varying exposure-outcome associations using case-control data: logistic and case-cohort analyses.

PubMed

Keogh, Ruth H; Mangtani, Punam; Rodrigues, Laura; Nguipdop Djomo, Patrick

2016-01-05

Traditional analyses of standard case-control studies using logistic regression do not allow estimation of time-varying associations between exposures and the outcome. We present two approaches which allow this. The motivation is a study of vaccine efficacy as a function of time since vaccination. Our first approach is to estimate time-varying exposure-outcome associations by fitting a series of logistic regressions within successive time periods, reusing controls across periods. Our second approach treats the case-control sample as a case-cohort study, with the controls forming the subcohort. In the case-cohort analysis, controls contribute information at all times they are at risk. Extensions allow left truncation, frequency matching and, using the case-cohort analysis, time-varying exposures. Simulations are used to investigate the methods. The simulation results show that both methods give correct estimates of time-varying effects of exposures using standard case-control data. Using the logistic approach there are efficiency gains by reusing controls over time and care should be taken over the definition of controls within time periods. However, using the case-cohort analysis there is no ambiguity over the definition of controls. The performance of the two analyses is very similar when controls are used most efficiently under the logistic approach. Using our methods, case-control studies can be used to estimate time-varying exposure-outcome associations where they may not previously have been considered. The case-cohort analysis has several advantages, including that it allows estimation of time-varying associations as a continuous function of time, while the logistic regression approach is restricted to assuming a step function form for the time-varying association.

Association Between Smoking Status, Preoperative Exhaled Carbon Monoxide Levels, and Postoperative Surgical Site Infection in Patients Undergoing Elective Surgery

PubMed Central

Martin, David P.; Thompson, Rodney; Schroeder, Darrell R.; Hanson, Andrew C.; Warner, David O.

2017-01-01

Importance Cigarette smoking is a risk factor for many perioperative complications, including surgical site infection (SSI). The duration of abstinence from smoking required to reduce this risk is unknown. Objectives To evaluate if abstinence from smoking on the day of surgery is associated with a decreased frequency of SSI in patients who smoke cigarettes and to confirm that smoking is significantly independently associated with SSI when adjustment is made for potentially relevant covariates, such as body mass index. Design, Setting, and Participants In this observational, nested, matched case-control study, 2 analyses were performed at an academic referral center in the upper Midwest. Cases included all patients undergoing elective surgical procedures at Mayo Clinic, Rochester, Minnesota, between January 1, 2009, and July 31, 2014 (inclusive) who subsequently developed an SSI. Controls for both analyses were matched on age, sex, and type of surgery. Exposures Smoking status and preoperative exhaled carbon monoxide level, assessed by nurses in the preoperative holding area. Patients were classified as smoking on the day of surgery if they self-reported smoking or if their preoperative exhaled carbon monoxide level was 10 ppm or higher. Main Outcomes and Measures Surgical site infection after a surgical procedure at Mayo Clinic, Rochester, as identified by routine clinical surveillance using National Healthcare Safety Network criteria. Results Of the 6919 patients in the first analysis, 3282 (47%) were men and 3637 (53%) were women; median age (interquartile range) for control and SSI cases was 60 (48-70). Of the 392 patients in the second analysis, 182 (46%) were men and 210 (54%) were women; median age (interquartile range) for controls was 53 (45-49) and for SSI cases was 51 (45-60). During the study period, approximately 2% of surgical patients developed SSI annually. Available for the first analysis (evaluating the influence of current smoking status) were 2452 SSI cases matched to 4467 controls. The odds ratio for smoking and SSI was 1.51 (95% CI, 1.20-1.90; P < .001), which remained statistically significant after adjusting for covariates. In the second analysis (evaluating the influence of smoking on the day of surgery), there were 137 SSI cases matched to 255 controls. The odds ratio for smoking on the day of surgery and SSI was 1.96 (95% CI, 1.23-3.13; P < .001), which remained statistically significant after adjusting for covariates. Preoperative exhaled carbon monoxide level was not associated with the frequency of SSI, suggesting that the association between smoking on the day of surgery and SSI was not related to preoperative exhaled carbon monoxide levels. Conclusions and Relevance Current smoking is associated with the development of SSI, and smoking on the day of surgery is independently associated with the development of SSI. These data cannot distinguish whether abstinence per se reduces risk or whether it is associated with other factors that may be causative. PMID:28199450

Case Selection via Matching

ERIC Educational Resources Information Center

Nielsen, Richard A.

2016-01-01

This article shows how statistical matching methods can be used to select "most similar" cases for qualitative analysis. I first offer a methodological justification for research designs based on selecting most similar cases. I then discuss the applicability of existing matching methods to the task of selecting most similar cases and…

Substantially Higher and Earlier Occurrence of Anti-Tuberculosis Drug-Related Adverse Reactions in HIV Coinfected Tuberculosis Patients: A Matched-Cohort Study.

PubMed

Matono, Takashi; Nishijima, Takeshi; Teruya, Katsuji; Morino, Eriko; Takasaki, Jin; Gatanaga, Hiroyuki; Kikuchi, Yoshimi; Kaku, Mitsuo; Oka, Shinichi

2017-11-01

Little information exists on the frequency, severity, and timing of first-line anti-tuberculosis drug-related adverse events (TB-AEs) in HIV-tuberculosis coinfected (HIV-TB) patients in the antiretroviral therapy (ART) era. This matched-cohort study included HIV-TB patients as cases and HIV-uninfected tuberculosis (non-HIV-TB) patients as controls. Tuberculosis was culture-confirmed in both groups. Cases were matched to controls in a 1:4 ratio on age, sex, and year of diagnosis. TB-AEs were defined as Grade 2 or higher requiring drug discontinuation/regimen change. From 2003 to 2015, 94 cases and 376 controls were analyzed (95% men, 98% Asians). Standard four-drug combination therapy was initiated in 91% of cases and 89% of controls (p = 0.45). Cases had a higher frequency of TB-AE [51% (48/94) vs. 10% (39/376), p < 0.001]. Their major TB-AEs were fever (19%), rash (11%), and neutropenia (11%). TB-AEs were more severe in cases [Grade 3 or higher: cases (71%, 34/48) vs. controls (49%, 19/39), p < 0.001]. The time from treatment initiation to TB-AE was shorter in cases [median 18 (interquartile range 12-28) vs. 27 (15-57) days, p = 0.027], and 73% of TB-AEs in cases occurred within 4 weeks of starting anti-tuberculosis treatment. HIV infection was an independent risk factor for TB-AEs in the multivariate Cox analysis [adjusted HR (aHR): 6.96; 95% confidence interval: 3.93-12.3]. TB-AEs occurred more frequently in HIV-TB than in non-HIV-TB patients, and were more severe. The majority of TB-AEs occurred within 4 weeks of initiating anti-tuberculosis treatment. Because TB-AEs may delay ART initiation, careful monitoring during this period is warranted in coinfected patients.

Spatial clustering of malaria and associated risk factors during an epidemic in a highland area of western Kenya.

PubMed

Brooker, Simon; Clarke, Siân; Njagi, Joseph Kiambo; Polack, Sarah; Mugo, Benbolt; Estambale, Benson; Muchiri, Eric; Magnussen, Pascal; Cox, Jonathan

2004-07-01

The epidemiology of malaria over small areas remains poorly understood, and this is particularly true for malaria during epidemics in highland areas of Africa, where transmission intensity is low and characterized by acute within and between year variations. We report an analysis of the spatial distribution of clinical malaria during an epidemic and investigate putative risk factors. Active case surveillance was undertaken in three schools in Nandi District, Western Kenya for 10 weeks during a malaria outbreak in May-July 2002. Household surveys of cases and age-matched controls were conducted to collect information on household construction, exposure factors and socio-economic status. Household geographical location and altitude were determined using a hand-held geographical positioning system and landcover types were determined using high spatial resolution satellite sensor data. Among 129 cases identified during the surveillance, which were matched to 155 controls, we identified significant spatial clusters of malaria cases as determined using the spatial scan statistic. Conditional multiple logistic regression analysis showed that the risk of malaria was higher in children who were underweight, who lived at lower altitudes, and who lived in households where drugs were not kept at home. Copyright 2004 Blackwell Publishing Ltd

Traffic rule violations of private bus drivers and bus crashes in Sri Lanka: a case-control study.

PubMed

Jayatilleke, Achala Upendra; Poudel, Krishna C; Nakahara, Shinji; Dharmaratne, Samath D; Jayatilleke, Achini Chinthika; Jimba, Masamine

2010-06-01

To explore the association between self-reported traffic rule violations of private sector bus drivers and bus crashes in the Kandy district, Sri Lanka. We carried out a case-control study from August to September 2006. Cases were all the private bus drivers registered in the Kandy district and involved in crashes reported to the police between November 2005 and April 2006 (n = 63). We included two control groups: the private bus drivers working on the same routes of the cases (n = 90; matched controls) and the drivers selected randomly from the other routes of the district (n = 111; unmatched controls). We used a self-administered questionnaire to collect data on the self-reported traffic rule violations and analyzed the association between the self-reported traffic rule violations and crashes using logistic regression. The following variables showed significant associations with private bus crashes: illegal overtaking (matched controls, adjusted odds ratio [AOR] = 14.78, unmatched controls, AOR = 1.04), taking passengers outside the bus bays (matched controls, AOR = 3.96, unmatched controls, AOR = 2.29), and overloading (matched controls, AOR = 10.26, unmatched controls, AOR = 1.93). However, we did not observe an association between high-speed driving and bus crashes matched controls, AOR = 1.22, unmatched controls, AOR = 0.81. Traffic rule violations, such as illegal overtaking, overloading, and taking passengers outside the bus bays, are significant risk factors for private bus crashes in Sri Lanka.

Outbreak of Neisseria meningitidis C in workers at a large food-processing plant in Brazil: challenges of controlling disease spread to the larger community.

PubMed

Iser, B P M; Lima, H C A V; de Moraes, C; de Almeida, R P A; Watanabe, L T; Alves, S L A; Lemos, A P S; Gorla, M C O; Gonçalves, M G; Dos Santos, D A; Sobel, J

2012-05-01

SUMMARYAn outbreak of meningococcal disease (MD) with severe morbidity and mortality was investigated in midwestern Brazil in order to identify control measures. A MD case was defined as isolation of Neisseria meningitidis, or detection of polysaccharide antigen in a sterile site, or presence of clinical purpura fulminans, or an epidemiological link with a laboratory-confirmed case-patient, between June and August 2008. In 8 out of 16 MD cases studied, serogroup C ST103 complex was identified. Five (31%) cases had neurological findings and five (31%) died. The attack rate was 12 cases/100 000 town residents and 60 cases/100 000 employees in a large local food-processing plant. We conducted a matched case-control study of eight primary laboratory-confirmed cases (1:4). Factors associated with illness in single variable analysis were work at the processing plant [matched odds ratio (mOR) 22, 95% confidence interval (CI) 2·3-207·7, P<0·01], and residing <1 year in Rio Verde (mOR 7, 95% CI 1·11-43·9, P<0·02). Mass vaccination (>10 000 plant employees) stopped propagation in the plant, but not in the larger community.

The lack of selection bias in a snowball sampled case-control study on drug abuse.

PubMed

Lopes, C S; Rodrigues, L C; Sichieri, R

1996-12-01

Friend controls in matched case-control studies can be a potential source of bias based on the assumption that friends are more likely to share exposure factors. This study evaluates the role of selection bias in a case-control study that used the snowball sampling method based on friendship for the selection of cases and controls. The cases selected fro the study were drug abusers located in the community. Exposure was defined by the presence of at least one psychiatric diagnosis. Psychiatric and drug abuse/dependence diagnoses were made according to the Diagnostic and Statistical Manual of Mental Disorders (DSM-III-R) criteria. Cases and controls were matched on sex, age and friendship. The measurement of selection bias was made through the comparison of the proportion of exposed controls selected by exposed cases (p1) with the proportion of exposed controls selected by unexposed cases (p2). If p1 = p2 then, selection bias should not occur. The observed distribution of the 185 matched pairs having at least one psychiatric disorder showed a p1 value of 0.52 and a p2 value of 0.51, indicating no selection bias in this study. Our findings support the idea that the use of friend controls can produce a valid basis for a case-control study.

Vitamin D deficiency in first episode psychosis: a case-control study.

PubMed

Crews, Matthieu; Lally, John; Gardner-Sood, Poonam; Howes, Oliver; Bonaccorso, Stefania; Smith, Shubulade; Murray, Robin M; Di Forti, Marta; Gaughran, Fiona

2013-11-01

Vitamin D deficiency is seen in a high proportion of people with established psychotic disorders, but it is not known if this is present at onset of the illness. We set out to examine vitamin D levels in people with their first episode of psychosis (FEP). We conducted a matched case-control study to examine vitamin D levels and rates of vitamin D deficiency in sixty nine patients presenting with their FEP and sixty nine controls matched for age, sex and ethnicity. Differences between groups were tested using student's-t tests, paired t-tests and odds ratios for further analysis. Vitamin D levels were significantly lower in cases than in controls (p<0.001). The odds ratio of being vitamin D deficient was 2.99 in the FEP group relative to the control group. There was no correlation between vitamin D levels and length of hospitalisation in the patient group (r=-0.027, p=0.827). We found higher rates of vitamin D deficiency in people with FEP compared to matched controls. Given that vitamin D is neuroprotective; that developmental vitamin D deficiency may be a risk factor for psychosis, and that incipient psychosis may affect lifestyle factors and diet, future studies are required to examine this association further. In the meantime, there is a need for more widespread testing of vitamin D levels in FEP and for the development of appropriate management strategies. © 2013 Elsevier B.V. All rights reserved.

Leveraging public health's participation in a Health Information Exchange to improve communicable disease reporting.

PubMed

Painter, Ian; Revere, Debra; Gibson, P Joseph; Baseman, Janet

2017-01-01

Infectious diseases can appear and spread rapidly. Timely information about disease patterns and trends allows public health agencies to quickly investigate and efficiently contain those diseases. But disease case reporting to public health has traditionally been paper-based, resulting in somewhat slow, burdensome processes. Fortunately, the expanding use of electronic health records and health information exchanges has created opportunities for more rapid, complete, and easily managed case reporting and investigation. To assess how this new service might impact the efficiency and quality of a public health agency's case investigations, we compared the timeliness of usual case investigation to that of case investigations based on case report forms that were partially pre-populated with electronic data. Between September 2013-March 2014, chlamydia disease report forms for certain clinics in Indianapolis were electronically pre-populated with clinical, lab and patient data available through the Indiana Health Information Exchange, then provided to the patient’s doctor. Doctors could then sign the form and deliver it to public health for investigation and population-level disease tracking. Methods: We utilized a novel matched case analysis of timeliness changes in receipt and processing of communicable disease report forms. Each Chlamydia cases reported with the pre-populated form were matched to cases reported in usual ways. We assessed the time from receipt of the case at the public health agency: 1) inclusion of the case into the public health surveillance system and 2) to close to case. A hierarchical random effects model was used to compare mean difference in each outcome between the target cases and the matched cases, with random intercepts for case. Twenty-one Chlamydia cases were reported to the public health agency using the pre-populated form. Sixteen of these pre-populated form cases were matched to at least one other case, with a mean of 23 matches per case. The mean Reporting Lag for the pre-populated form cases was 2.5 days, which was 2.7 days shorter than the mean Reporting Lag for the matched controls (p = <0.001). The mean time to close a pre-populated form case was 4.7 days, which was 0.2 days shorter than time to close for the matched controls (p = 0.792). Use of pre-populated forms significantly decreased the time it took for the local public health agency to begin documenting and closing chlamydia case investigations. Thoughtful use of electronic health data for case reporting may decrease the per-case workload of public health agencies, and improve the timeliness of information about the pattern and spread of disease.

Serum Vitamin D Is Significantly Inversely Associated with Disease Severity in Caucasian Adults with Obstructive Sleep Apnea Syndrome.

PubMed

Kerley, Conor P; Hutchinson, Katrina; Bolger, Kenneth; McGowan, Aisling; Faul, John; Cormican, Liam

2016-02-01

To evaluate vitamin D (25(OH)D) levels in obstructive sleep apnea syndrome (OSAS) and possible relationships to OSAS severity, sleepiness, lung function, nocturnal heart rate (HR), and body composition. We also aimed to compare the 25(OH)D status of a subset of OSAS patients compared to controls matched for important determinants of both OSAS and vitamin D deficiency (VDD). This was a cross-sectional study conducted at an urban, clinical sleep medicine outpatient center. We recruited newly diagnosed, Caucasian adults who had recently undergone nocturnal polysomnography. We compared body mass index (BMI), body composition (bioelectrical impedance analysis), neck circumference, sleepiness (Epworth Sleepiness Scale), lung function, and vitamin D status (serum 25-hydrpoxyvitamin D (25(OH)D) across OSAS severity categories and non-OSAS subjects. Next, using a case-control design, we compared measures of serum 25(OH)D from OSAS cases to non-OSAS controls who were matched for age, gender, skin pigmentation, sleepiness, season, and BMI. 106 adults (77 male; median age = 54.5; median BMI = 34.3 kg/m(2)) resident in Dublin, Ireland (latitude 53°N) were recruited and categorized as non-OSAS or mild/moderate/severe OSAS. 98% of OSAS cases had insufficient 25(OH)D (< 75 nmol/L), including 72% with VDD (< 50 nmol/L). 25(OH)D levels decreased with OSAS severity (P = 0.003). 25(OH)D was inversely correlated with BMI, percent body fat, AHI, and nocturnal HR. Subsequent multivariate regression analysis revealed that 25(OH)D was independently associated with both AHI (P = 0.016) and nocturnal HR (P = 0.0419). Our separate case-control study revealed that 25(OH)D was significantly lower in OSAS cases than matched, non-OSAS subjects (P = 0.001). We observed widespread vitamin D deficiency and insufficiency in a Caucasian, OSAS population. There were significant, independent, inverse relationships between 25(OH)D and AHI as well as nocturnal HR, a known cardiovascular risk factor. Further, 25(OH)D was significantly lower in OSAS cases compared to matched, non-OSAS subjects. We provide evidence that 25(OH)D and OSAS are related, but the role, if any, of replenishment has not been investigated. © 2016 Associated Professional Sleep Societies, LLC.

Child Maltreatment as a Risk Factor for Opioid Dependence: Comparison of Family Characteristics and Type and Severity of Child Maltreatment with a Matched Control Group

ERIC Educational Resources Information Center

Conroy, Elizabeth; Degenhardt, Louisa; Mattick, Richard P.; Nelson, Elliot C.

2009-01-01

Objective: To examine the prevalence, characteristics and risk factors for child maltreatment among opioid-dependent persons compared to a community sample of similar social disadvantage. Method: The study employed a case-control design. Cases had a history of opioid pharmacotherapy. Controls were frequency matched to cases with regard to age, sex…

Risk factors for syphilis infection in men who have sex with men: results of a case-control study in Lille, France.

PubMed

Champenois, Karen; Cousien, Anthony; Ndiaye, Bakhao; Soukouna, Yougoudou; Baclet, Véronique; Alcaraz, Isabelle; Choisy, Philippe; Chaud, Pascal; Velter, Annie; Gallay, Anne; Yazdanpanah, Yazdan

2013-03-01

Substantial increases in syphilis have been reported since the early 2000s in northern countries, particularly among men who have sex with men (MSM). The authors aimed to identify risk factors for early syphilis in MSM in Lille, a large urban area of northern France. A matched case-control study was conducted in MSM aged ≥ 18 years. Cases were diagnosed with primary, secondary or early latent syphilis between April 2008 and June 2010. Controls sought care in STIs clinics or were followed in an HIV clinic. Controls had no history of and no current syphilis. They were matched to cases for age and HIV status. Multivariate conditional logistic regression models were used to identify risk factors for early syphilis. 53 patients with early syphilis were enrolled. Average age was 37 years, and 47% were HIV-infected. For analysis, they were matched to 90 controls. Factors associated with syphilis were: low educational attainment (OR=5.38, 95% CI 1.94 to 14.94; p=0.001), receptive oral sex with casual male partners without a condom (OR=4.86, 95% CI 1.63 to 14.48; p=0.005) and anal sex toy use with casual male partners (OR=2.72, 95% CI 1.01 to 7.32; p=0.05). Seeking of sex partners online (OR=5.17, 95% CI 1.33 to 20.11), use of poppers (OR=2.2, 95% CI 1.1 to 4.3) and erectile dysfunction drugs (OR=1.9, 95% CI 1.0 to 13.2) were associated with syphilis only in the univariate analysis. Receptive oral sex without a condom and use of anal sex toys were identified as presenting a major risk of syphilis infection. Although these practices have been shown to present low risk of HIV transmission, the general public is unaware of their impact on transmission of other STIs.

Association of young and advanced age of pregnant women with the risk of isolated congenital abnormalities in Hungary - a population-based case-matched control study.

PubMed

Csermely, Gyula; Susánszky, Éva; Czeizel, Andrew E

2015-03-01

To analyze the possible association of maternal age with the risk of all congenital abnormalities (CAs) in a population-based large case-matched control data set. The Hungarian Case-Control Surveillance of Congenital Abnormalities included 21,494 cases with isolated CA and their 34,311 matched controls. First the distribution of maternal age groups in 24 CA-groups and their matched controls was compared. In the second step, young (19 years or less) and advanced (35 years or more) age groups were compared. Finally, the subgroups of neural-tube defects, congenital heart defects and abdominal wall's CA were evaluated separately. A higher risk of gastroschisis, congenital heart defects, particularly left-sided obstructive defects, undescended testis and clubfoot was found in the youngest age group (19 years or less) of cases. The higher proportion of pregnant women with advanced age (i.e. 35 years or more) showed only a borderline excess in cases with clubfoot. The so-called U-shaped risk of maternal age distribution was found in cases with clubfoot and in the total group of isolated CAs. The maternal age is a contributing factor to the origin of some isolated CAs mainly in young pregnant women.

Electrocardiographic features of sudden unexpected death in epilepsy.

PubMed

Chyou, Janice Y; Friedman, Daniel; Cerrone, Marina; Slater, William; Guo, Yu; Taupin, Daniel; O'Rourke, Sean; Priori, Silvia G; Devinsky, Orrin

2016-07-01

Sudden unexpected death in epilepsy (SUDEP) is the most common cause of epilepsy-related mortality. We hypothesized that electrocardiography (ECG) features may distinguish SUDEP cases from living subjects with epilepsy. Using a matched case-control design, we compared ECG studies of 12 consecutive cases of SUDEP over 10 years and 22 epilepsy controls matched for age, sex, epilepsy type (focal, generalized, or unknown/mixed type), concomitant antiepileptic, and psychotropic drug classes. Conduction intervals and prevalence of abnormal ventricular conduction diagnosis (QRS ≥110 msec), abnormal ventricular conduction pattern (QRS <110 msec, morphology of incomplete right or left bundle branch block or intraventricular conduction delay), early repolarization, and features of inherited cardiac channelopathies were assessed. Abnormal ventricular conduction diagnosis and pattern distinguished SUDEP cases from matched controls. Abnormal ventricular conduction diagnosis was present in two cases and no controls. Abnormal ventricular conduction pattern was more common in cases than controls (58% vs. 18%, p = 0.04). Early repolarization was similarly prevalent in cases and controls, but the overall prevalence exceeded that of published community-based cohorts. Wiley Periodicals, Inc. © 2016 International League Against Epilepsy.

Decreased hospital length of stay associated with presentation of cases at morning report with librarian support

PubMed Central

Banks, Daniel E.; Shi, Runhua; Timm, Donna F.; Christopher, Kerri Ann; Duggar, David Charles; Comegys, Marianne; McLarty, Jerry

2007-01-01

Objective: The research sought to determine whether case discussion at residents' morning report (MR), accompanied by a computerized literature search and librarian support, affects hospital charges, length of stay (LOS), and thirty-day readmission rate. Methods: This case-control study, conducted from August 2004 to March 2005, compared outcomes for 105 cases presented at MR within 24 hours of admission to 19,210 potential matches, including cases presented at MR and cases not presented at MR. With matching criteria of patient age (± 5 years), identical primary diagnosis, and secondary diagnoses (within 3 additional diagnoses) using International Classification of Diseases (ICD-9) codes, 55 cases were matched to 136 controls. Statistical analyses included Student's t tests, chi-squared tests, and nonparametric methods. Results: LOS differed significantly between matched MR cases and controls (3 days vs. 5 days, P < 0.024). Median total hospital charges were $7,045 for the MR group and $10,663 for the control group. There was no difference in 30-day readmission rate between the 2 groups. Discussion/Conclusion: Presentation of a case at MR, followed by the timely dissemination of the results of an online literature review, resulted in a shortened LOS and lower hospital charges compared with controls. MR, in association with a computerized literature search guided by the librarians, was an effective means for introducing evidence-based medicine into patient care practices. PMID:17971885

The utility of the Kohlman Evaluation of Living Skills test is associated with substantiated cases of elder self-neglect.

PubMed

Pickens, Sabrina; Naik, Aanand D; Burnett, Jason; Kelly, P A; Gleason, Mary; Dyer, Carmel B

2007-03-01

Self-neglect is the most prevalent finding among cases reported to Adult Protective Services (APS) and is characterized by an inability to meet one's own basic needs. The Kohlman evaluation of living skills (KELS) has been validated in geriatric populations to assess performance with both instrumental and basic activities of daily living and as an assessment tool for the capacity to live independently; therefore, the purpose of this analysis was to compare the scores of the KELS between substantiated cases of self-neglect and matched community-dwelling elders. This is a cross-sectional pilot study of 50 adults aged 65 years and older who were recruited from APS as documented cases of self-neglect and 50 control participants recruited from Harris County Hospital District outpatient clinics. Control participants were matched for age, race, gender, and ZIP code. A geriatric nurse practitioner (NP)-led team administered a comprehensive geriatric assessment in homes of all study participants. The assessment included the KELS and mini-mental state examination (MMSE) tests. Chi-square analyses were used to determine if cases of self-neglect were significantly more likely to fail the KELS test than matched controls. The analyses revealed that self-neglectors were significantly more likely to fail the KELS than non-self-neglectors (50% vs. 30%, p = .025). When stratified by MMSE scores, self-neglectors with intact cognitive function remained significantly more likely to fail the KELS compared to matched, cognitively intact controls (45% vs. 17%, p = .013). Abnormal results using an in-home KELS test were significantly associated with substantiated cases of self-neglect. There is currently no gold-standard measure for identifying capacity with self-care behaviors among cases of self-neglect. As a result, self-neglect may remain unidentified in many clinical settings. The KELS provides clinicians with an objective measure of an individual's capacity and performance with everyday life-supporting tasks and thus, provides information that can help NPs identify elders at risk for self-neglect. These findings suggest that the KELS test has significant utility as part of a comprehensive geriatric assessment to aid clinicians in suspected cases of self-neglect.

Critical issues in ALS case-control studies: the case of the Euro-MOTOR study.

PubMed

D'Ovidio, Fabrizio; Rooney, James P K; Visser, Anne E; Vermeulen, Roel C H; Veldink, Jan H; Van Den Berg, Leonard H; Hardiman, Orla; Logroscino, Giancarlo; Chiò, Adriano; Beghi, Ettore

2017-08-01

Backround: Political and sociocultural differences between countries can affect the outcome of clinical and epidemiological studies in ALS. Cross-national studies represent the ideal process by which risk factors can be assessed using the same methodology in different geographical areas. A survey of three European countries (The Netherlands, Ireland and Italy) has been conducted in which incident ALS patients and matched controls were recruited in a population-based study based on age, gender and area of residency, under the Euro-MOTOR systems biology programme of research. We have identified strengths and limitations during the trajectory of the Euro-MOTOR study, from the research design to data analysis. We have analysed the implications of factors including cross-national differences in healthcare systems, sample size, types of matching, the definition of exposures and statistical analysis. Addressing critical methodological aspects of the design of the Euro-MOTOR project minimises bias and will facilitate scientific assessment of the independent role of well-defined exposures.

Novel application of the matched case-control design to compare food supply chains during an Escherichia coli O157 outbreak, United Kingdom, 2016.

PubMed

Inns, Thomas; Cleary, Paul; Bundle, Nick; Foulkes, Sarah; Sharp, Ashley; Utsi, Lara; McBrien, Chris; Teagle, Rehman; Waldram, Alison; Williams, Chris; McCann, Cathy; Smith, Rob; Saleh, Sepeedeh; McCarthy, Noel; Vivancos, Roberto; Hawker, Jeremy; Decraene, Valerie

2018-05-01

There is a need for innovative methods to investigate outbreaks of food-borne infection linked to produce with a complex distribution network. The investigation of a large outbreak of Escherichia coli O157 PT34 infection in the United Kingdom in 2016 indicated that catering venues associated with multiple cases had used salad leaves sourced from one supplier. Our aim was to investigate whether catering venues linked to cases were more likely to have used salad leaves from this supplier. We conducted a matched case-control study, with catering venues as the units of analysis. We compared venues linked to cases to those without known linked cases. We included 43 study pairs and obtained information on salad leaf products received by each venue. The odds of a case venue being supplied with salad leaves by Supplier A were 7.67 times (95% confidence interval: 2.30-25.53) those of control venues. This association provided statistical evidence to support the findings of the other epidemiological investigations undertaken for this outbreak. This is a novel approach which is labour-intensive but which addresses the challenge of investigating exposures to food across a complex distribution network.

Association of HLA-B*5801 allele and allopurinol-induced stevens johnson syndrome and toxic epidermal necrolysis: a systematic review and meta-analysis

PubMed Central

2011-01-01

Background Despite some studies suggesting a possible association between human leukocyte antigen, HLA-B*5801 and allopurinol induced Stevens-Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN), the evidence of association and its magnitude remain inconclusive. This study aims to systematically review and meta-analyze the association between HLA-B*5801 allele and allopurinol-induced SJS/TEN. Methods A comprehensive search was performed in databases including MEDLINE, Pre-MEDLINE, Cochrane Library, EMBASE, International Pharmaceutical Abstracts (IPA), CINAHL, PsychInfo, the WHO International, Clinical Trial Registry, and ClinicalTrial.gov from their inceptions to June 2011. Only studies investigating association between HLA-B*5801 with allopurinol-induced SJS/TEN were included. All studies were extracted by two independent authors. The primary analysis was the carrier frequency of HLA-B*5801 comparison between allopurinol-induced SJS/TEN cases and each comparative group. The pooled odds ratios were calculated using a random effect model. Results A total of 4 studies with 55 SJS/TEN cases and 678 matched-controls (allopurinol-tolerant control) was identified, while 5 studies with 69 SJS/TEN cases and 3378 population-controls (general population) were found. SJS/TEN cases were found to be significantly associated with HLA-B*5801 allele in both groups of studies with matched-control (OR 96.60, 95%CI 24.49-381.00, p < 0.001) and population-control (OR 79.28, 95%CI 41.51-151.35, p < 0.001). Subgroup analysis for Asian and Non-Asian population yielded similar findings. Conclusion We found a strong and significant association between HLA-B*5801 and allopurinol-induced SJS/TEN. Therefore, HLA-B*5801 allele screening may be considered in patients who will be treated with allopurinol. PMID:21906289

[Risk factors for patent ductus arteriosus in early preterm infants: a case-control study].

PubMed

Du, Jin-Feng; Liu, Tian-Tian; Wu, Hui

2016-01-01

To investigate the risk factors for the occurrence of patent ductus arteriosus (PDA) and to provide a clinical basis for reducing the occurrence of PDA in early preterm infants. A total of 136 early preterm infants (gestational age≤32 weeks) who were hospitalized between January 2013 and December 2014 and diagnosed with hemodynamicalhy significant PDA (hs-PDA) were enrolled as the case group. Based on the matched case-control principle, 136 early preterm infants without hs-PDA were selected among those who were hospitalized within the same period at a ratio of 1:1 and enrolled as the control group. The two groups were matched for sex and gestational age. The basic information of neonates and maternal conditions during the pregnancy and perinatal periods were collected. Logistic regression analysis was performed to identify the risk factors for the development of PDA. Univariate analysis showed that neonatal infectious diseases, neonatal respiratory distress syndrome, decreased platelet count within 24 hours after birth, and low birth weight were associated with the development of hs-PDA (P<0.05). Multivariate conditional logistic regression analysis revealed that neonatal infectious diseases (OR=2.368) and decreased platelet count within 24 hours after birth (OR=0.996) were independent risk factors for hs-PDA. Neonatal infectious diseases and decreased platelet count within 24 hours after birth increase the risk of hs-PDA in early preterm infants.

Association between plasma triglycerides and high-density lipoprotein cholesterol and microvascular kidney disease and retinopathy in type 2 diabetes mellitus: a global case-control study in 13 countries.

PubMed

Sacks, Frank M; Hermans, Michel P; Fioretto, Paola; Valensi, Paul; Davis, Timothy; Horton, Edward; Wanner, Christoph; Al-Rubeaan, Khalid; Aronson, Ronnie; Barzon, Isabella; Bishop, Louise; Bonora, Enzo; Bunnag, Pongamorn; Chuang, Lee-Ming; Deerochanawong, Chaicharn; Goldenberg, Ronald; Harshfield, Benjamin; Hernández, Cristina; Herzlinger-Botein, Susan; Itoh, Hiroshi; Jia, Weiping; Jiang, Yi-Der; Kadowaki, Takashi; Laranjo, Nancy; Leiter, Lawrence; Miwa, Takashi; Odawara, Masato; Ohashi, Ken; Ohno, Atsushi; Pan, Changyu; Pan, Jiemin; Pedro-Botet, Juan; Reiner, Zeljko; Rotella, Carlo Maria; Simo, Rafael; Tanaka, Masami; Tedeschi-Reiner, Eugenia; Twum-Barima, David; Zoppini, Giacomo; Carey, Vincent J

2014-03-04

Microvascular renal and retinal diseases are common major complications of type 2 diabetes mellitus. The relation between plasma lipids and microvascular disease is not well established. The case subjects were 2535 patients with type 2 diabetes mellitus with an average duration of 14 years, 1891 of whom had kidney disease and 1218 with retinopathy. The case subjects were matched for diabetes mellitus duration, age, sex, and low-density lipoprotein cholesterol to 3683 control subjects with type 2 diabetes mellitus who did not have kidney disease or retinopathy. The study was conducted in 24 sites in 13 countries. The primary analysis included kidney disease and retinopathy cases. Matched analysis was performed by use of site-specific conditional logistic regression in multivariable models that adjusted for hemoglobin A1c, hypertension, and statin treatment. Mean low-density lipoprotein cholesterol concentration was 2.3 mmol/L. The microvascular disease odds ratio increased by a factor of 1.16 (95% confidence interval, 1.11-1.22) for every 0.5 mmol/L (≈1 quintile) increase in triglycerides or decreased by a factor of 0.92 (0.88-0.96) for every 0.2 mmol/L (≈1 quintile) increase in high-density lipoprotein cholesterol. For kidney disease, the odds ratio increased by 1.23 (1.16-1.31) with triglycerides and decreased by 0.86 (0.82-0.91) with high-density lipoprotein cholesterol. Retinopathy was associated with triglycerides and high-density lipoprotein cholesterol in matched analysis but not significantly after additional adjustment. Diabetic kidney disease is associated worldwide with higher levels of plasma triglycerides and lower levels of high-density lipoprotein cholesterol among patients with good control of low-density lipoprotein cholesterol. Retinopathy was less robustly associated with these lipids. These results strengthen the rationale for studying dyslipidemia treatment to prevent diabetic microvascular disease.

Return to Sport and Performance After Microfracture in the Knees of National Basketball Association Players

PubMed Central

Harris, Joshua D.; Walton, David M.; Erickson, Brandon J.; Verma, Nikhil N.; Abrams, Geoffrey D.; Bush-Joseph, Charles A.; Bach, Bernard R.; Cole, Brian J.

2013-01-01

Background: Use of microfracture in the knees of National Basketball Association (NBA) players is controversial. Hypotheses: (1) There would be a high rate of return to sport (RTS) in NBA players following microfracture, (2) players would RTS the season following surgery, (3) preoperative player performance would not be significantly different on RTS, and (4) there would be no significant difference in RTS rate or postoperative performance in players undergoing microfracture in comparison with an age-, position-, NBA experience–, and performance-matched control group. Study Design: Cohort study; Level of evidence, 3. Methods: NBA players undergoing microfracture were evaluated. Age-, body mass index–, position-, NBA experience–, and performance-matched controls were selected from the NBA during the same years as those undergoing microfracture. An index year was selected (controls) to match the number of seasons of NBA experience in microfracture cases. RTS and performance were analyzed and compared between cases and controls. Student t tests were performed for analysis of within- and between-group variables. Results: A total of 41 NBA players underwent microfracture and were compared with 41 demographic- and performance-matched controls. Rate of RTS after microfracture was 73% in the NBA and 83% in professional basketball (NBA, D-league, and International Basketball Federation [FIBA]). Time to RTS in NBA was 9.20 ± 4.88 months. Seventy-one percent (29/41) of players RTS the season following microfracture. Length of NBA career following microfracture (4.10 ± 3.91 years) was not significantly different from controls. After microfracture, case athletes played fewer games per season and with fewer points and steals per game (relative to premicrofracture; P < .05). Performance was better in control (after index year) versus case players (after microfracture) with regard to points per game, games played per season, and field goal and free throw percentage (P < .05). Conclusion: Eighty-three percent of NBA players undergoing microfracture returned to professional basketball. Career length was not significantly different between players undergoing microfracture and controls. However, following microfracture, players competed in fewer games per season with fewer points and steals. PMID:26535256

Return to Sport and Performance After Microfracture in the Knees of National Basketball Association Players.

PubMed

Harris, Joshua D; Walton, David M; Erickson, Brandon J; Verma, Nikhil N; Abrams, Geoffrey D; Bush-Joseph, Charles A; Bach, Bernard R; Cole, Brian J

2013-11-01

Use of microfracture in the knees of National Basketball Association (NBA) players is controversial. (1) There would be a high rate of return to sport (RTS) in NBA players following microfracture, (2) players would RTS the season following surgery, (3) preoperative player performance would not be significantly different on RTS, and (4) there would be no significant difference in RTS rate or postoperative performance in players undergoing microfracture in comparison with an age-, position-, NBA experience-, and performance-matched control group. Cohort study; Level of evidence, 3. NBA players undergoing microfracture were evaluated. Age-, body mass index-, position-, NBA experience-, and performance-matched controls were selected from the NBA during the same years as those undergoing microfracture. An index year was selected (controls) to match the number of seasons of NBA experience in microfracture cases. RTS and performance were analyzed and compared between cases and controls. Student t tests were performed for analysis of within- and between-group variables. A total of 41 NBA players underwent microfracture and were compared with 41 demographic- and performance-matched controls. Rate of RTS after microfracture was 73% in the NBA and 83% in professional basketball (NBA, D-league, and International Basketball Federation [FIBA]). Time to RTS in NBA was 9.20 ± 4.88 months. Seventy-one percent (29/41) of players RTS the season following microfracture. Length of NBA career following microfracture (4.10 ± 3.91 years) was not significantly different from controls. After microfracture, case athletes played fewer games per season and with fewer points and steals per game (relative to premicrofracture; P < .05). Performance was better in control (after index year) versus case players (after microfracture) with regard to points per game, games played per season, and field goal and free throw percentage (P < .05). Eighty-three percent of NBA players undergoing microfracture returned to professional basketball. Career length was not significantly different between players undergoing microfracture and controls. However, following microfracture, players competed in fewer games per season with fewer points and steals.

Matched samples logistic regression in case-control studies with missing values: when to break the matches.

PubMed

Hansson, Lisbeth; Khamis, Harry J

2008-12-01

Simulated data sets are used to evaluate conditional and unconditional maximum likelihood estimation in an individual case-control design with continuous covariates when there are different rates of excluded cases and different levels of other design parameters. The effectiveness of the estimation procedures is measured by method bias, variance of the estimators, root mean square error (RMSE) for logistic regression and the percentage of explained variation. Conditional estimation leads to higher RMSE than unconditional estimation in the presence of missing observations, especially for 1:1 matching. The RMSE is higher for the smaller stratum size, especially for the 1:1 matching. The percentage of explained variation appears to be insensitive to missing data, but is generally higher for the conditional estimation than for the unconditional estimation. It is particularly good for the 1:2 matching design. For minimizing RMSE, a high matching ratio is recommended; in this case, conditional and unconditional logistic regression models yield comparable levels of effectiveness. For maximizing the percentage of explained variation, the 1:2 matching design with the conditional logistic regression model is recommended.

The Association Between Neurocysticercosis and Hippocampal Atrophy is Related to Age

PubMed Central

Del Brutto, Oscar H.; Issa, Naoum P.; Salgado, Perla; Del Brutto, Victor J.; Zambrano, Mauricio; Lama, Julio; García, Héctor H.

2017-01-01

Neurocysticercosis (NCC) has been associated with hippocampal atrophy, but the prevalence and pathogenic mechanisms implicated in this relationship are unknown. Using a population-based, case–control study design, residents in a rural village (Atahualpa) aged ≥ 40 years with calcified NCC were identified as cases and paired to NCC-free individuals (control subjects) matched by age, sex, and level of education. Cases and control subjects underwent magnetic resonance imaging for hippocampal rating according to the Scheltens' scale for medial temporal atrophy and were interviewed to identify those with a clinical seizure disorder. The prevalence of hippocampal atrophy was compared between cases and control subjects by the use of the McNemar's test for correlated proportions. Seventy-five individuals with calcified NCC and their matched control subjects were included in the analysis. Hippocampal atrophy was noted in 26 (34.7%) cases and nine (12%) control subjects (odds ratio: 4.4; 95% confidence interval: 1.6–14.9, P < 0.0021). Stratification of pairs according to tertiles of age revealed an age-related trend in this association, which became significant only in those aged ≥ 68 years (P = 0.027). Only five cases and one control had recurrent seizures (P = 0.221); three of these five cases had hippocampal atrophy, and the single control subject had normal hippocampi. This study confirms an association between NCC and hippocampal atrophy, and shows that this association is stronger in older age groups. This suggests that NCC-related hippocampal atrophy takes a long time to develop. PMID:28077750

[The case-case-time-control study design].

PubMed

Wang, Jing; Zhuo, Lin; Zhan, Siyan

2014-12-01

Although the 'self-matched case-only studies' (such as the case-cross-over or self-controlled case-series method) can control the time-invariant confounders (measured or unmeasured) through design of the study, however, they can not control those confounders that vary with time. A bidirectional case-crossover design can be used to adjust the exposure-time trends. In the areas of pharmaco-epidemiology, illness often influence the future use of medications, making a bidirectional study design problematic. Suissa's case-time-control design combines the case-crossover and the case-control design which could adjust for exposure-trend bias, but the control group may reintroduce selection bias, if the matching does not go well. We propose a "case-case-time-control" design which is an extension of the case-time-control design. However, rather than using a sample of external controls, we choose those future cases as controls for current cases to counter the bias that arising from temporal trends caused by exposure to the target of interest. In the end of this article we will discuss the strength and limitations of this design based on an applied example.

Effectiveness of penicillin, dicloxacillin and cefuroxime for penicillin-susceptible Staphylococcus aureus bacteraemia: a retrospective, propensity-score-adjusted case-control and cohort analysis.

PubMed

Nissen, Jette Lindbjerg; Skov, Robert; Knudsen, Jenny Dahl; Ostergaard, Christian; Schønheyder, Henrik Carl; Frimodt-Møller, Niels; Benfield, Thomas

2013-08-01

Penicillin-susceptible Staphylococcus aureus isolates account for a fifth of cases of S. aureus bacteraemia (SAB) in Denmark, but little is known about treatment outcomes with penicillins or other antimicrobials. Here we compare penicillin, dicloxacillin and cefuroxime as definitive treatments in relation to 30 day mortality. A retrospective chart review of 588 penicillin-susceptible S. aureus cases at five centres from January 1995 to December 2010. Data on demographics, antimicrobial treatment, clinical signs and symptoms, and mortality at day 30 were collected. Hazard ratios (HRs) with 95% CIs associated with mortality were modelled using propensity-score-adjusted Cox proportional hazards regression analysis. Propensity-score-matched case-control studies were carried out. Definitive therapy with cefuroxime was associated with an increased risk of 30 day mortality compared with penicillin (adjusted HR 2.54, 95% CI 1.49-4.32). Other variables that were statistically significantly associated with 30 day mortality included increasing age, disease severity and a primary respiratory focus. Osteomyelitis/arthritis was associated with a lower risk of death than were other secondary manifestations. Propensity-score-matched case-control studies confirmed an increased risk of 30 day mortality: cefuroxime treatment (39%) versus penicillin treatment (20%), P = 0.037; and cefuroxime treatment (38%) versus dicloxacillin treatment (10%), P = 0.004. Definitive therapy for penicillin-susceptible SAB with cefuroxime was associated with a significantly higher mortality than was seen with therapy with penicillin or dicloxacillin.

Outcome of Intravenous Azithromycin Therapy in Patients with Complicated Scrub Typhus Compared with That of Doxycycline Therapy Using Propensity-Matched Analysis

PubMed Central

Jang, Mi-Ok; Jang, Hee-Chang; Kim, Uh Jin; Ahn, Joon Hwan; Kang, Seung-Ji; Jung, Sook-In; Shin, Hee-Young

2014-01-01

There are no well-matched, controlled studies comparing azithromycin with doxycycline for the treatment of complicated scrub typhus. A retrospective propensity score-matched case-control study was performed for patients who presented with complicated scrub typhus and were treated with doxycycline or azithromycin between 2001 and 2011. Data on comorbidities, clinical manifestations, laboratory studies, treatments, and outcomes were extracted for analysis. The clinical characteristics and outcomes of the azithromycin-treated group (n = 73) were compared to those of the doxycycline-treated group (n = 108). Of 181 patients, 73 from each group were matched by propensity scores. There were no significant differences in baseline characteristics between the matched groups. The treatment success and survival rates were not significantly different (89% [65/73 patients] versus 96% [70/73 patients] and 96% [70/73 patients] versus 96% [70/73 patients], respectively [P > 0.05]). No difference was observed in the time to defervescence or length of hospital stay between the two groups (P > 0.05). In complicated scrub typhus patients (n = 181), multivariate analysis showed that only APACHE II score was an independent risk factor for mortality (95% confidence interval, 1.11 to 1.56; P < 0.001). Our data suggest that outcomes of azithromycin therapy are comparable to those of doxycycline therapy in patients with complicated scrub typhus. PMID:24366734

pN0(i+) Breast Cancer: Treatment Patterns, Locoregional Recurrence, and Survival Outcomes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Karam, Irene; Breast Cancer Outcomes Unit, British Columbia Cancer Agency, Vancouver, BC; Lesperance, Maria F.

Purpose: To examine treatment patterns, recurrence, and survival outcomes in patients with pN0(i+) breast cancer. Methods and Materials: Subjects were 5999 women with AJCC (6th edition) pT1-3, pN0-N1a, M0 breast cancer diagnosed between 2003 and 2006. Of these, 4342 (72%) had pN0, 96 (2%) had pN0(i+), 349 (6%) had pNmic (micrometastases >0.2 mm to ≤2 mm), and 1212 (20%) had pN1a (1-3 positive macroscopic nodes) disease. Treatment characteristics and 5-year Kaplan-Meier local recurrence, regional recurrence (RR), locoregional recurrence (LRR), and overall survival were compared between nodal subgroups. Multivariable analysis was performed using Cox regression modeling. A 1:3 case-match analysis examinedmore » outcomes in pN0(i+) cases compared with pN0 controls matched for similar tumor and treatment characteristics. Results: Median follow-up was 4.8 years. Adjuvant systemic therapy use increased with nodal stage: 81%, 92%, 95%, and 94% in pN0, pN0(i+), pNmic, and pN1a disease, respectively (P<.001). Nodal radiation therapy (RT) use also increased with nodal stage: 1.7% in pN0, 27% in pN0(i+), 33% in pNmic, and 63% in pN1a cohorts (P<.001). Five-year Kaplan-Meier outcomes in pN0 versus pN0(i+) cases were as follows: local recurrence 1.7% versus 3.7% (P=.20), RR 0.5% versus 2.2% (P=.02), and LRR 2.1% versus 5.8% (P=.02). There were no RR events in 26 patients with pN0(i+) disease who received nodal RT and 2 RR events in 70 patients who did not receive nodal RT. On multivariable analysis, pN0(i+) was not associated with worse locoregional control or survival. On case-match analysis, LRR and overall survival were similar between pN0(i+) and matched pN0 counterparts. Conclusions: Nodal involvement with isolated tumor cells is not a significant prognostic factor for LRR or survival in this study's multivariable and case-match analyses. These data do not support the routine use of nodal RT in the setting of pN0(i+) disease. Prospective studies are needed to define optimal locoregional management for women with pN0(i+) breast cancer.« less

Risk and protective factors for meningococcal disease in adolescents: matched cohort study.

PubMed

Tully, Joanna; Viner, Russell M; Coen, Pietro G; Stuart, James M; Zambon, Maria; Peckham, Catherine; Booth, Clare; Klein, Nigel; Kaczmarski, Ed; Booy, Robert

2006-02-25

To examine biological and social risk factors for meningococcal disease in adolescents. Prospective, population based, matched cohort study with controls matched for age and sex in 1:1 matching. Controls were sought from the general practitioner. Six contiguous regions of England, which represent some 65% of the country's population. 15-19 year olds with meningococcal disease recruited at hospital admission in six regions (representing 65% of the population of England) from January 1999 to June 2000, and their matched controls. Blood samples and pernasal and throat swabs were taken from case patients at admission to hospital and from cases and matched controls at interview. Data on potential risk factors were gathered by confidential interview. Data were analysed by using univariate and multivariate conditional logistic regression. 144 case control pairs were recruited (74 male (51%); median age 17.6). 114 cases (79%) were confirmed microbiologically. Significant independent risk factors for meningococcal disease were history of preceding illness (matched odds ratio 2.9, 95% confidence interval 1.4 to 5.9), intimate kissing with multiple partners (3.7, 1.7 to 8.1), being a university student (3.4, 1.2 to 10) and preterm birth (3.7, 1.0 to 13.5). Religious observance (0.09, 0.02 to 0.6) and meningococcal vaccination (0.12, 0.04 to 0.4) were associated with protection. Activities and events increasing risk for meningococcal disease in adolescence are different from in childhood. Students are at higher risk. Altering personal behaviours could moderate the risk. However, the development of further effective meningococcal vaccines remains a key public health priority.

Tight Bounds for Minimax Grid Matching, with Applications to the Average Case Analysis of Algorithms.

DTIC Science & Technology

1986-05-01

AD-ft?l 552 TIGHT BOUNDS FOR NININAX GRID MATCHING WITH i APPLICATIONS TO THE AVERAGE C.. (U) MASSACHUSETTS INST OF TECH CAMBRIDGE LAS FOR COMPUTER...MASSACHUSETTS LABORATORYFORNSTITUTE OF COMPUTER SCIENCE TECHNOLOGY MIT/LCS/TM-298 TIGHT BOUNDS FOR MINIMAX GRID MATCHING, WITH APPLICATIONS TO THE AVERAGE...PERIOD COVERED Tight bounds for minimax grid matching, Interim research with applications to the average case May 1986 analysis of algorithms. 6

Long term outcome of neonatal meningitis

PubMed Central

Stevens, J; Eames, M; Kent, A; Halket, S; Holt, D; Harvey, D

2003-01-01

Objectives: To quantify long term impairment after neonatal meningitis. Design: Longitudinal case-control study over 9–10 years. Subjects and methods: A total of 111 children who had suffered neonatal meningitis were seen and compared with 113 matched controls from their birth hospital and 49 controls from general practices. Assessments included the WISC IIIUK , movement assessment battery for children (mABC), audiometry, vision testing, and social and medical data. Statistical analysis was by multiple regression, analysis of variance, and χ2 tests. Results: Some 10.8% of cases had a severe and 9% a moderate overall outcome compared with 0% and 1.8% for the hospital controls. The mean intelligence quotient (IQ) of the cases (88.8) was significantly less than that of the hospital controls (99.4) or the GP controls (99.6) . The mABC score was significantly worse for the cases (7.08) than the hospital (5) or GP (4) controls. Some 3.6% of cases had sensorineural hearing loss, 2.7% had persisting hydrocephalus; no controls did. Some 5.4% of cases and 1.7% of hospital controls had treatment for seizures. Conclusions: Severe neurodisability and milder motor and psychometric impairment result from neonatal meningitis. Both clinical follow up and comprehensive developmental assessment are needed after this disease. PMID:12719389

[Method to calculate the additional hospital stay in patients with cross infection].

PubMed

Angeles-Garay, Ulises; Velázquez-Chávez, Yesenia; Molinar-Ramos, Fernando; Anaya-Flores, Verónica E; Uribe-Márquez, Samuel E

2009-01-01

To calculate additional hospital stay due to specific cross infection. Cases and controls study; matched by age +/- 2 years, sex, specialty in which were taken care, diagnosis, surgical procedure and hospitalization stay, between July 2005-June 2006. t test, chi(2) to calculate death risk, Kaplan-Meier analysis to calculate survival, Hosmer-Lemeshow test to know the contribution of cross infection for additional hospital stay due to cross infection (AHSDCI). We identified 851 patients with 1347 cross infection in 16 528 discharges. We could match 677. The cases stayed 25.42 days and the controls 13.29 (p < 0.01). The death risk for the cases was 5.8 (CI 95 % = 3.7-8.6, p < 0.01), four weeks survival 55.3 % for cases and 79.2 % for the controls. The AHSDCI for pneumonia was 10.39 days, urinary-tract-infection 6.28, bacteremia 8.92, vascular-catheter-related infection 3.31, surgical site infections 7.42, and skin and soft-tissue-infection 3.31 (p < 0.05). We used a multivariate model fitted to patient's gravity and complexity to extract the proportion days of AHSDCI of each cross infection.

Continuous Positive Airway Pressure Adherence In Patients with Obstructive Sleep Apnea & Symptomatic BPH.

PubMed

Metta, Ramesh V V S; Zaka, Awais; Lee, Vincent C; Mador, M Jeffery

2017-04-01

Purpose To determine the short-term and long-term adherence rates with continuous positive airway pressure (CPAP) therapy in sleep apnea patients with benign prostatic hyperplasia (BPH) compared to matched controls. Methods A case-control retrospective analysis was performed in a veterans affairs hospital. All symptomatic patients with BPH (n = 107) ever started on CPAP therapy between 2006 and 2012 were compared with controls matched for severity of sleep apnea (AHI). Adherence measures were obtained at the third and twelfth month visits. The cases included symptomatic BPH patients on active medical therapy. Diuretic use among cases and controls, and severity of nocturia among the cases were also analyzed. Results The mean AHI among cases and controls was 35.6 ± 27.3 and 35.5 ± 31 (p = 0.96). The population was male and predominantly Caucasian. There was no statistically significant difference in percent days CPAP device use ≥4 h. between symptomatic BPH patients and controls at 3-month (51.6 ± 38 vs. 47.2 ± 36; p = 0.43) and 1-year (64 ± 40.5 vs. 64.7 ± 31.3; p = 0.90) visits. The use of diuretics in the cases and controls, and the severity of nocturia in the cases did not influence adherence with CPAP therapy. Conclusions BPH or diuretic use did not affect adherence with CPAP therapy in obstructive sleep apnea. Severity of nocturia did not have any influence on adherence among the cases. BPH, regardless of the severity of nocturia, and diuretic use does not influence CPAP adherence in patients with OSA.

Patterns of Migration and Risks Associated with Leprosy among Migrants in Maranhão, Brazil

PubMed Central

Murto, Christine; Chammartin, Frédérique; Schwarz, Karolin; da Costa, Lea Marcia Melo; Kaplan, Charles; Heukelbach, Jorg

2013-01-01

Leprosy remains a public health problem in Brazil with new case incidence exceeding World Health Organization (WHO) goals in endemic clusters throughout the country. Migration can facilitate movement of disease between endemic and non-endemic areas, and has been considered a possible factor in continued leprosy incidence in Brazil. A study was conducted to investigate migration as a risk factor for leprosy. The study had three aims: (1) examine past five year migration as a risk factor for leprosy, (2) describe and compare geographic and temporal patterns of migration among past 5-year migrants with leprosy and a control group, and (3) examine social determinants of health associated with leprosy among past 5-year migrants. The study implemented a matched case-control design and analysis comparing individuals newly diagnosed with leprosy (n = 340) and a clinically unapparent control group (n = 340) without clinical signs of leprosy, matched for age, sex and location in four endemic municipalities in the state of Maranhão, northeastern Brazil. Fishers exact test was used to conduct bivariate analyses. A multivariate logistic regression analysis was employed to control for possible confounding variables. Eighty cases (23.5%) migrated 5-years prior to diagnosis, and 55 controls (16.2%) migrated 5-years prior to the corresponding case diagnosis. Past 5 year migration was found to be associated with leprosy (OR: 1.59; 95% CI 1.07–2.38; p = 0.02), and remained significantly associated with leprosy after controlling for leprosy contact in the family, household, and family/household contact. Poverty, as well as leprosy contact in the family, household and other leprosy contact, was associated with leprosy among past 5-year migrants in the bivariate analysis. Alcohol consumption was also associated with leprosy, a relevant risk factor in susceptibility to infection that should be explored in future research. Our findings provide insight into patterns of migration to localize focused control efforts in endemic areas with high population mobility. PMID:24040433

Statin use is associated with reduced risk of histologic subtypes of esophageal cancer: a nested case-control analysis.

PubMed

Alexandre, Leo; Clark, Allan B; Bhutta, Hina Y; Holt, Sean; Lewis, Michael P N; Hart, Andrew R

2014-03-01

Most patients with esophageal adenocarcinoma (EAC) or squamous cell cancer (ESCC) present with advanced, incurable disease. Statins have reported anti-carcinogenic effects and may be chemoprotective. We investigated the association between regular use of statins and the main histologic subtypes of esophageal malignancy (EAC, esophagogastric junctional adenocarcinoma, and ESCC) in the UK general population. We identified all individuals in the UK General Practice Research Database diagnosed with esophageal cancer from 2000 through 2009. Patients were linked to the National Cancer Registry to confirm histologic subtypes. Each patient was matched with up to 4 controls for age, sex, and practice. We performed a nested case-control analysis using conditional logistic regression to estimate the risk of each subtype with regular statin use, adjusted for body mass index, smoking, alcohol intake, and concomitant use of medications. In total, 581 participants with EAC, 213 with esophagogastric junctional adenocarcinoma, and 332 with ESCC were matched to 2167, 783, and 1242 controls, respectively. Regular statin use was inversely associated with development of EAC (odds ratio = 0.58; 95% confidence interval: 0.39-0.87) (with significant dose and duration responses) and esophagogastric junctional adenocarcinoma (odds ratio = 0.29; 95% confidence interval: 0.09-0.92) (with high-dose use only). Statin use for 1-4 years was inversely associated with ESCC (odds ratio = 0.51; 95% confidence interval: 0.27-0.98). In a nested case-control analysis of a UK population-based cohort, statin use was inversely associated with histologic subtypes of esophageal cancer. Randomized controlled trials are warranted to determine whether statins have chemopreventive effects in high-risk groups. Copyright © 2014 AGA Institute. Published by Elsevier Inc. All rights reserved.

Determinants of unwanted pregnancies in India using matched case-control designs.

PubMed

Dixit, Priyanka; Ram, Faujdar; Dwivedi, Laxmi Kant

2012-08-11

In India, while the total fertility rate has been declined from 3.39 in 1992-93 to 2.68 in 2005-06, the prevalence of unintended pregnancy is still stagnant over the same period. A review of existing literature shows that within the country, there are variations in fertility preferences between different regions. Also there is a strong argument that the availability of a health facility at the village level plays an important role in reshaping the fertility behavior of women. Keeping in mind the fact that there is no information at the village level (which is the lowest geographical boundary) in the recent round of National Family Health Survey (NFHS-3), the specific objective of this study is to examine the impact of individual and household level variables on unwanted pregnancies without controlling the village level variation. Further, once the village level variation (i.e. unobserved variation) has been controlled, it is necessary to study whether there has been any alteration in the contribution of factors from earlier results of without adjusting the village level variation. This paper attempts to examine the associated factors of unwanted pregnancies, without matching the village and after matching the village, by using the matched case-control design. Nationwide data from India's latest NFHS-3 conducted during 2005-06 was used for the present study. Frequency and pair wise matching has been applied in the present paper and conditional logistic regression analysis was used to work out the models and to find out the factors associated with unwanted pregnancies. A major finding of this study was that 1:3 case-control study (without matching the village) shows that women belonging to non Hindu/Muslim religion, Scheduled Tribe, women who have experienced child loss and if the previous birth interval is 24 through 36 months were significant predictors of unwanted pregnancy. However, this relationship did not hold significant after village wise matching. Other factors such as Muslim religion, women and their partners with high school education and above, women belonging to the richest wealth index and if the sex of the last child was female, emerge as significant predictors of unwanted pregnancies. This study clearly underscores the importance of adjusting the village (PSU) level variation in explaining unwanted pregnancies.

The financial impact of heparin-induced thrombocytopenia.

PubMed

Smythe, Maureen A; Koerber, John M; Fitzgerald, Maureen; Mattson, Joan C

2008-09-01

Heparin-induced thrombocytopenia (HIT) is an adverse drug reaction that increases patient morbidity and mortality. The financial impact of HIT to an institution is thought to be significant. The objective of this study was to evaluate the financial impact of HIT. A case-control study was employed. Case patients were identified as newly diagnosed HIT patients. Control subjects were matched by diagnosis-related group, primary diagnosis code, primary procedure code, and hospital admission date. The financial/decision support database of the hospital was queried to identify the matched control subjects, total cost, and reimbursement. The determination of financial impact included the total profit or (total loss) and the backfill effect (ie, the lost operating margin resulting from increased length of stay). Length of stay and mortality were compared. Data from 22 case patients and 255 control subjects were analyzed. On average, HIT case patients incurred a financial loss of $14,387 per patient and an increase in length of stay of 14.5 days. When confining the analysis to only Medicare case patients (n = 17) and Medicare control subjects, case patients incurred a financial loss of $20,170 per case and an increase in length of stay of 15.8 days. Depending on the occupancy rate of the institution, additional financial loss could result from the backfill effect. Mortality was not significantly affected. For an institution that sees 50 new cases of HIT per year, the projected annual financial impact ranges from approximately $700,000 to $1 million. Institutions with high bed occupancy rates may see an additional loss from the backfill effect.

German outbreak of Escherichia coli O104:H4 associated with sprouts.

PubMed

Buchholz, Udo; Bernard, Helen; Werber, Dirk; Böhmer, Merle M; Remschmidt, Cornelius; Wilking, Hendrik; Deleré, Yvonne; an der Heiden, Matthias; Adlhoch, Cornelia; Dreesman, Johannes; Ehlers, Joachim; Ethelberg, Steen; Faber, Mirko; Frank, Christina; Fricke, Gerd; Greiner, Matthias; Höhle, Michael; Ivarsson, Sofie; Jark, Uwe; Kirchner, Markus; Koch, Judith; Krause, Gérard; Luber, Petra; Rosner, Bettina; Stark, Klaus; Kühne, Michael

2011-11-10

A large outbreak of the hemolytic-uremic syndrome caused by Shiga-toxin-producing Escherichia coli O104:H4 occurred in Germany in May 2011. The source of infection was undetermined. We conducted a matched case-control study and a recipe-based restaurant cohort study, along with environmental, trace-back, and trace-forward investigations, to determine the source of infection. The case-control study included 26 case subjects with the hemolytic-uremic syndrome and 81 control subjects. The outbreak of illness was associated with sprout consumption in univariable analysis (matched odds ratio, 5.8; 95% confidence interval [CI], 1.2 to 29) and with sprout and cucumber consumption in multivariable analysis. Among case subjects, 25% reported having eaten sprouts, and 88% reported having eaten cucumbers. The recipe-based study among 10 groups of visitors to restaurant K included 152 persons, among whom bloody diarrhea or diarrhea confirmed to be associated with Shiga-toxin-producing E. coli developed in 31 (20%). Visitors who were served sprouts were significantly more likely to become ill (relative risk, 14.2; 95% CI, 2.6 to ∞). Sprout consumption explained 100% of cases. Trace-back investigation of sprouts from the distributor that supplied restaurant K led to producer A. All 41 case clusters with known trading connections could be explained by producer A. The outbreak strain could not be identified on seeds from the implicated lot. Our investigations identified sprouts as the most likely outbreak vehicle, underlining the need to take into account food items that may be overlooked during subjects' recall of consumption.

Proton Pump Inhibitor use as a risk factor for Enterobacteriaceal infection: a case-control study.

PubMed

Cunningham, Richard; Jones, Lewis; Enki, Doyo Gragn; Tischhauser, Robert

2018-06-01

Gastric acid suppressants increase the risk of gastroenteritis by allowing ingested pathogens to survive passage through the stomach. It is not known whether the same mechanism affects transmission of Enterobacteriacae. We carried out a case-control study to answer this question. To determine whether use of Proton Pump Inhibitors (PPIs) increases the risk of infection with Enterobacteriacae in hospital patients. Retrospective case-control study in a teaching hospital in South West England. Cases were 126 patients infected with extended-spectrum beta-lactamase producing Enterobacteriacae (ESBL) between April 2014 and March 2015. Use of PPIs, H2 receptor antagonists or antacids at the time of admission or in the preceding six months was compared with 126 demographically matched controls infected with non-ESBL producing Enterobacteriacae and 126 uninfected controls, matched by primary diagnosis. 66 of 126 ESBL cases, 62 of 126 non-ESBL controls and 34 of 126 uninfected controls were prescribed PPIs on or within 6 months of admission. Multivariable logistic regression analysis gave an Odds Ratio (95% confidence interval) of 3.37 (1.84 - 6.18) for PPI exposure versus uninfected controls and 1.15 (0.68 - 1.95) for ESBL infection versus non-ESBL infection. H2RA and antacids were not significantly associated with infection. PPI exposure within the previous 6 months is significantly associated with infection with both ESBL and non-ESBL producing bacteria. Reducing inappropriate use of PPIs may be a novel way of reducing transmission, which might reduce antibiotic use and help control antimicrobial resistance. Copyright © 2018. Published by Elsevier Ltd.

A case-matched study of neurophysiological correlates to attention/working memory in people with somatic hypervigilance.

PubMed

Berryman, Carolyn; Wise, Vikki; Stanton, Tasha R; McFarlane, Alexander; Moseley, G Lorimer

2017-02-01

Somatic hypervigilance describes a clinical presentation in which people report more, and more intense, bodily sensations than is usual. Most explanations of somatic hypervigilance implicate altered information processing, but strong empirical data are lacking. Attention and working memory are critical for information processing, and we aimed to evaluate brain activity during attention/working memory tasks in people with and without somatic hypervigilance. Data from 173 people with somatic hypervigilance and 173 controls matched for age, gender, handedness, and years of education were analyzed. Event-related potential (ERP) data, extracted from the continuous electroencephalograph recordings obtained during performance of the Auditory Oddball task, and the Two In A Row (TIAR) task, for N1, P2, N2, and P3, were used in the analysis. Between-group differences for P3 amplitude and N2 amplitude and latency were assessed with two-tailed independent t tests. Between-group differences for N1 and P2 amplitude and latency were assessed using mixed, repeated measures analyses of variance (ANOVAs) with group and Group × Site factors. Linear regression analysis investigated the relationship between anxiety and depression and any outcomes of significance. People with somatic hypervigilance showed smaller P3 amplitudes-Auditory Oddball task: t(285) = 2.32, 95% confidence interval, CI [3.48, 4.47], p = .026, d = 0.27; Two-In-A-Row (TIAR) task: t(334) = 2.23, 95% CI [2.20; 3.95], p = .021, d = 0.24-than case-matched controls. N2 amplitude was also smaller in people with somatic hypervigilance-TIAR task: t(318) = 2.58, 95% CI [0.33, 2.47], p = .010, d = 0.29-than in case-matched controls. Neither depression nor anxiety was significantly associated with any outcome. People with somatic hypervigilance demonstrated an event-related potential response to attention/working memory tasks that is consistent with altered information processing.

Plasma carotenoids, retinol, and tocopherols and postmenopausal breast cancer risk in the Multiethnic Cohort Study: a nested case-control study

PubMed Central

Epplein, Meira; Shvetsov, Yurii B; Wilkens, Lynne R; Franke, Adrian A; Cooney, Robert V; Le Marchand, Loïc; Henderson, Brian E; Kolonel, Laurence N; Goodman, Marc T

2009-01-01

Introduction Assessments by the handful of prospective studies of the association of serum antioxidants and breast cancer risk have yielded inconsistent results. This multiethnic nested case-control study sought to examine the association of plasma carotenoids, retinol, and tocopherols with postmenopausal breast cancer risk. Methods From the biospecimen subcohort of the Multiethnic Cohort Study, 286 incident postmenopausal breast cancer cases were matched to 535 controls on age, sex, ethnicity, study location (Hawaii or California), smoking status, date/time of collection and hours of fasting. We measured prediagnostic circulating levels of individual carotenoids, retinol, and tocopherols. Conditional logistic regression was used to compute odds ratios and 95% confidence intervals. Results Women with breast cancer tended to have lower levels of plasma carotenoids and tocopherols than matched controls, but the differences were not large or statistically significant and the trends were not monotonic. No association was seen with retinol. A sensitivity analysis excluding cases diagnosed within 1 year after blood draw did not alter the findings. Conclusions The lack of significant associations in this multiethnic population is consistent with previously observed results from less racially-diverse cohorts and serves as further evidence against a causal link between plasma micronutrient concentrations and postmenopausal breast cancer risk. PMID:19619335

The cost of absenteeism and short-term disability associated with colorectal cancer: a case-control study.

PubMed

Yaldo, Avin; Seal, Brian S; Lage, Maureen J

2014-08-01

Examine the incremental impact of absenteeism and short-term disability associated with colorectal cancer (CRC). Absenteeism and short-term disability data were used for a case-control analysis of a healthy cohort (controls) compared with CRC patients (cases). Cases were matched to controls on the basis of age, sex, and region of residence. Multivariate regression models examined the costs of absenteeism and short-term disability, controlling for patient characteristics, prior medical costs, and patient general health. Compared with controls, CRC patients experience significantly higher short-term disability costs (mean, $45,716 vs $7367 [P < 0.0001]; median, $35,827 vs $7365 [P < 0.0001]), as well as significantly higher absenteeism costs (mean, $8841 vs $4596 [P < 0.0001]; median, $9971 vs $4795 [P < 0.0001]) in the 1 year after diagnosis of CRC. Colorectal cancer is associated with significant work-related productivity loss costs in the first year after diagnosis.

Energy Impairments in Older Adults with Low Back Pain and Radiculopathy: A Matched Case-Control Study.

PubMed

Coyle, Peter C; Pugliese, Jenifer M; Sions, J Megan; Eskander, Mark S; Schrack, Jennifer A; Hicks, Gregory E

2018-04-23

To investigate the impact that the presence of chronic low back pain with radiculopathy (CLBPR) may have on 1) energy efficiency and 2) energy capacity among community-dwelling older adults. Matched case-control study. Clinical research laboratory. 38 community-dwelling older adults (60-85 years) with (n=19) and without (n=19) CLBPR were included in this analysis. Participants were matched between-groups on age (± 5 years), sex, and diabetic status. Not applicable. Energy cost of walking at self-selected speed (i.e. energy efficiency) and Peak Walking VO2 (i.e. energy capacity). Older adults with CLBPR had a higher energy cost of walking at self-selected speed (p=.009) and lower Peak Walking VO2 (p=.050), compared to those without pain. Older adults with CLBPR may benefit from specific rehabilitative interventions that target these potentially modifiable energetic outcomes, thereby reducing the risk of mobility decline. Future studies should identify which mechanisms specifically contribute to diminished energy efficiency and capacity among older adults with CLBPR. Copyright © 2018. Published by Elsevier Inc.

Control selection and confounding factors: A lesson from a Japanese case-control study to examine acellular pertussis vaccine effectiveness.

PubMed

Ohfuji, Satoko; Okada, Kenji; Nakano, Takashi; Ito, Hiroaki; Hara, Megumi; Kuroki, Haruo; Hirota, Yoshio

2017-08-24

When using a case-control study design to examine vaccine effectiveness, both the selection of control subjects and the consideration of potential confounders must be the important issues to ensure accurate results. In this report, we described our experience from a case-control study conducted to evaluate the effectiveness of acellular pertussis vaccine combined with diphtheria-tetanus toxoids (DTaP vaccine). Newly diagnosed pertussis cases and age- and sex-matched friend-controls were enrolled, and the history of DTaP vaccination was compared between groups. Logistic regression models were used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) of vaccination for development of pertussis. After adjustment for potential confounders, four doses of DTaP vaccination showed a lower OR for pediatrician-diagnosed pertussis (OR=0.11, 95% CI, 0.01-0.99). In addition, the decreasing OR of four doses vaccination was more pronounced for laboratory-confirmed pertussis (OR=0.07, 95%CI, 0.01-0.82). Besides, positive association with pertussis was observed in subjects with a history of steroid treatment (OR=5.67) and those with a recent contact with a lasting cough (OR=4.12). When using a case-control study to evaluate the effectiveness of vaccines, particularly those for uncommon infectious diseases such as pertussis, the use of friend-controls may be optimal due to the fact that they shared a similar experience for exposure to the pathogen as the cases. In addition, to assess vaccine effectiveness as accurately as possible, the effects of confounding should be adequately controlled with a matching or analysis technique. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Frequency of and risk factors associated with catastrophic musculoskeletal injuries in Quarter Horses at two Midwestern racetracks: 67 cases (2000-2011).

PubMed

Beisser, Andrea; McClure, Scott; Rezabek, Grant; Soring, Keith H; Wang, Chong

2014-11-15

To determine the incidence and anatomic location of and potential risk factors for catastrophic musculoskeletal injuries (CMIs) in racing Quarter Horses. Retrospective matched case-control study. 67 racing Quarter Horse racehorses euthanized because of CMIs and 134 matched controls. Data for Quarter Horses that sustained CMIs and the total number of race starts for each year were obtained from 2 Midwestern racing jurisdictions from 2000 through 2011. Information for each horse with a CMI and for 2 randomly selected control horses that ran in the same race but did not incur a CMI were obtained from race records, past performance reports, and video analysis. There were 61,797 race starts and 82 CMIs from 2000 through 2011 at the 2 racetracks studied, for an overall CMI incidence of 1.33 CMIs/1,000 starts. Sixty-seven horses with CMIs for which complete data were available and 134 matched control horses were included in the study. There was no difference in the incidence of CMIs between the 2 racetracks or over the years studied. The right forelimb was injured in 38 of the 67 (56.7%) horses. Injures to the carpus (24/67 [35.8%]) and metacarpophalangeal joint (fetlock joint; 23/67 [34.3%]) occurred most frequently. Case-control data indicated that the horses with a CMI had fewer starts, were more likely to have stumbled at the break, had a more erratic stride, were fatigued, and trailed in the race, compared with matched controls from the same races. Irrespective of race distance, most of the horses (47/67 [70.1%]) were injured after or within 10 yards before the finish line. The results of the present study may aid in the identification of racing Quarter Horses at risk for CMIs. The cluster of injuries near the finish line provides a specific focus for future research into methods of injury prevention in this population of racehorses.

Joint Control: A Discussion of Recent Research

PubMed Central

Palmer, David C

2006-01-01

The discrimination of the onset of joint control is an important interpretive tool in explaining matching behavior and other complex phenomena, but the difficulty of getting experimental control of all relevant variables stands in the way of a definitive experiment. The studies in the present issue of The Analysis of Verbal Behavior illustrate how modest experiments can take their place in a web of interpretation to make a strong case that joint control is a necessary element of such phenomena. PMID:22477357

Asthma exacerbation and proximity of residence to major roads: a population-based matched case-control study among the pediatric Medicaid population in Detroit, Michigan

PubMed Central

2011-01-01

Background The relationship between asthma and traffic-related pollutants has received considerable attention. The use of individual-level exposure measures, such as residence location or proximity to emission sources, may avoid ecological biases. Method This study focused on the pediatric Medicaid population in Detroit, MI, a high-risk population for asthma-related events. A population-based matched case-control analysis was used to investigate associations between acute asthma outcomes and proximity of residence to major roads, including freeways. Asthma cases were identified as all children who made at least one asthma claim, including inpatient and emergency department visits, during the three-year study period, 2004-06. Individually matched controls were randomly selected from the rest of the Medicaid population on the basis of non-respiratory related illness. We used conditional logistic regression with distance as both categorical and continuous variables, and examined non-linear relationships with distance using polynomial splines. The conditional logistic regression models were then extended by considering multiple asthma states (based on the frequency of acute asthma outcomes) using polychotomous conditional logistic regression. Results Asthma events were associated with proximity to primary roads with an odds ratio of 0.97 (95% CI: 0.94, 0.99) for a 1 km increase in distance using conditional logistic regression, implying that asthma events are less likely as the distance between the residence and a primary road increases. Similar relationships and effect sizes were found using polychotomous conditional logistic regression. Another plausible exposure metric, a reduced form response surface model that represents atmospheric dispersion of pollutants from roads, was not associated under that exposure model. Conclusions There is moderately strong evidence of elevated risk of asthma close to major roads based on the results obtained in this population-based matched case-control study. PMID:21513554

Complexity analysis of fetal heart rate preceding intrauterine demise.

PubMed

Schnettler, William T; Goldberger, Ary L; Ralston, Steven J; Costa, Madalena

2016-08-01

Visual non-stress test interpretation lacks the optimal specificity and observer-agreement of an ideal screening tool for intrauterine fetal demise (IUFD) syndrome prevention. Computational methods based on traditional heart rate variability have also been of limited value. Complexity analysis probes properties of the dynamics of physiologic signals that are otherwise not accessible and, therefore, might be useful in this context. To explore the association between fetal heart rate (FHR) complexity analysis and subsequent IUFD. Our specific hypothesis is that the complexity of the fetal heart rate dynamics is lower in the IUFD group compared with controls. This case-control study utilized cases of IUFD at a single tertiary-care center among singleton pregnancies with at least 10min of continuous electronic FHR monitoring on at least 2 weekly occasions in the 3 weeks immediately prior to fetal demise. Controls delivered a live singleton beyond 35 weeks' gestation and were matched to cases by gestational age, testing indication, and maternal age in a 3:1 ratio. FHR data was analyzed using the multiscale entropy (MSE) method to derive their complexity index. In addition, pNNx, a measure of short-term heart rate variability, which in adults is ascribable primarily to cardiac vagal tone modulation, was also computed. 211 IUFDs occurred during the 9-year period of review, but only 6 met inclusion criteria. The median gestational age at the time of IUFD was 35.5 weeks. Three controls were matched to each case for a total of 24 subjects, and 87 FHR tracings were included for analysis. The median gestational age at the first fetal heart rate tracing was similar between groups (median [1st-3rd quartiles] weeks: IUFD cases: 34.7 (34.4-36.2); controls: 35.3 (34.4-36.1); p=.94). The median complexity of the cases' tracings was significantly less than the controls' (12.44 [8.9-16.77] vs. 17.82 [15.21-22.17]; p<.0001). Furthermore, the cases' median complexity decreased as gestation advanced whereas the controls' median complexity increased over time. However, this difference was not statistically significant [-0.83 (-2.03 to 0.47) vs. 0.14 (-1.25 to 0.94); p=.62]. The degree of short-term variability of FHR tracings, as measured by the pNN metric, was significantly lower (p<.005) for the controls (1.1 [0.8-1.3]) than the IUFD cases (1.3 [1.1-1.6]). FHR complexity analysis using multiscale entropy analysis may add value to other measures in detecting and monitoring pregnancies at the highest risk for IUFD. The decrease in complexity and short-term variability seen in the IUFD cases may reflect perturbations in neuroautonomic control due to multiple maternal-fetal factors. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Risk and protective factors for meningococcal disease in adolescents: matched cohort study

PubMed Central

Tully, Joanna; Viner, Russell M; Coen, Pietro G; Stuart, James M; Zambon, Maria; Peckham, Catherine; Booth, Clare; Klein, Nigel; Kaczmarski, Ed; Booy, Robert

2006-01-01

Objective To examine biological and social risk factors for meningococcal disease in adolescents. Design Prospective, population based, matched cohort study with controls matched for age and sex in 1:1 matching. Controls were sought from the general practitioner. Setting Six contiguous regions of England, which represent some 65% of the country's population. Participants 15-19 year olds with meningococcal disease recruited at hospital admission in six regions (representing 65% of the population of England) from January 1999 to June 2000, and their matched controls. Methods Blood samples and pernasal and throat swabs were taken from case patients at admission to hospital and from cases and matched controls at interview. Data on potential risk factors were gathered by confidential interview. Data were analysed by using univariate and multivariate conditional logistic regression. Results 144 case control pairs were recruited (74 male (51%); median age 17.6). 114 cases (79%) were confirmed microbiologically. Significant independent risk factors for meningococcal disease were history of preceding illness (matched odds ratio 2.9, 95% confidence interval 1.4 to 5.9), intimate kissing with multiple partners (3.7, 1.7 to 8.1), being a university student (3.4, 1.2 to 10) and preterm birth (3.7, 1.0 to 13.5). Religious observance (0.09, 0.02 to 0.6) and meningococcal vaccination (0.12, 0.04 to 0.4) were associated with protection. Conclusions Activities and events increasing risk for meningococcal disease in adolescence are different from in childhood. Students are at higher risk. Altering personal behaviours could moderate the risk. However, the development of further effective meningococcal vaccines remains a key public health priority. PMID:16473859

Use of the i2b2 research query tool to conduct a matched case-control clinical research study: advantages, disadvantages and methodological considerations.

PubMed

Johnson, Emilie K; Broder-Fingert, Sarabeth; Tanpowpong, Pornthep; Bickel, Jonathan; Lightdale, Jenifer R; Nelson, Caleb P

2014-01-30

A major aim of the i2b2 (informatics for integrating biology and the bedside) clinical data informatics framework aims to create an efficient structure within which patients can be identified for clinical and translational research projects.Our objective was to describe the respective roles of the i2b2 research query tool and the electronic medical record (EMR) in conducting a case-controlled clinical study at our institution. We analyzed the process of using i2b2 and the EMR together to generate a complete research database for a case-control study that sought to examine risk factors for kidney stones among gastrostomy tube (G-tube) fed children. Our final case cohort consisted of 41/177 (23%) of potential cases initially identified by i2b2, who were matched with 80/486 (17%) of potential controls. Cases were 10 times more likely to be excluded for inaccurate coding regarding stones vs. inaccurate coding regarding G-tubes. A majority (67%) of cases were excluded due to not meeting clinical inclusion criteria, whereas a majority of control exclusions (72%) occurred due to inadequate clinical data necessary for study completion. Full dataset assembly required complementary information from i2b2 and the EMR. i2b2 was critical as a query analysis tool for patient identification in our case-control study. Patient identification via procedural coding appeared more accurate compared with diagnosis coding. Completion of our investigation required iterative interplay of i2b2 and the EMR to assemble the study cohort.

Serum Vitamin D Is Significantly Inversely Associated with Disease Severity in Caucasian Adults with Obstructive Sleep Apnea Syndrome

PubMed Central

Kerley, Conor P.; Hutchinson, Katrina; Bolger, Kenneth; McGowan, Aisling; Faul, John; Cormican, Liam

2016-01-01

Study Objectives: To evaluate vitamin D (25(OH)D) levels in obstructive sleep apnea syndrome (OSAS) and possible relationships to OSAS severity, sleepiness, lung function, nocturnal heart rate (HR), and body composition. We also aimed to compare the 25(OH)D status of a subset of OSAS patients compared to controls matched for important determinants of both OSAS and vitamin D deficiency (VDD). Methods: This was a cross-sectional study conducted at an urban, clinical sleep medicine outpatient center. We recruited newly diagnosed, Caucasian adults who had recently undergone nocturnal polysomnography. We compared body mass index (BMI), body composition (bioelectrical impedance analysis), neck circumference, sleepiness (Epworth Sleepiness Scale), lung function, and vitamin D status (serum 25-hydrpoxyvitamin D (25(OH)D) across OSAS severity categories and non-OSAS subjects. Next, using a case-control design, we compared measures of serum 25(OH)D from OSAS cases to non-OSAS controls who were matched for age, gender, skin pigmentation, sleepiness, season, and BMI. Results: 106 adults (77 male; median age = 54.5; median BMI = 34.3 kg/m2) resident in Dublin, Ireland (latitude 53°N) were recruited and categorized as non-OSAS or mild/moderate/severe OSAS. 98% of OSAS cases had insufficient 25(OH)D (< 75 nmol/L), including 72% with VDD (< 50 nmol/L). 25(OH)D levels decreased with OSAS severity (P = 0.003). 25(OH)D was inversely correlated with BMI, percent body fat, AHI, and nocturnal HR. Subsequent multivariate regression analysis revealed that 25(OH)D was independently associated with both AHI (P = 0.016) and nocturnal HR (P = 0.0419). Our separate case-control study revealed that 25(OH)D was significantly lower in OSAS cases than matched, non-OSAS subjects (P = 0.001). Conclusions: We observed widespread vitamin D deficiency and insufficiency in a Caucasian, OSAS population. There were significant, independent, inverse relationships between 25(OH)D and AHI as well as nocturnal HR, a known cardiovascular risk factor. Further, 25(OH)D was significantly lower in OSAS cases compared to matched, non-OSAS subjects. We provide evidence that 25(OH)D and OSAS are related, but the role, if any, of replenishment has not been investigated. Citation: Kerley CP, Hutchinson K, Bolger K, McGowan A, Faul J, Comican L. Serum vitamin D is significantly inversely associated with disease severity in Caucasian adults with obstructive sleep apnea syndrome. SLEEP 2016;39(2):293–300. PMID:26414899

Argyrophilic grain disease as a neurodegenerative substrate in late-onset schizophrenia and delusional disorders.

PubMed

Nagao, Shigeto; Yokota, Osamu; Ikeda, Chikako; Takeda, Naoya; Ishizu, Hideki; Kuroda, Shigetoshi; Sudo, Koichiro; Terada, Seishi; Murayama, Shigeo; Uchitomi, Yosuke

2014-06-01

To study the relationship between neurodegenerative diseases including argyrophilic grain disease (AGD) and late-onset schizophrenia and delusional disorders (LOSD; onset ≥40 years of age), we pathologically examined 23 patients with LOSD, 71 age-matched normal controls, and 22 psychiatric disease controls (11 depression, six personality disorder, two bipolar disorders, and three neurotic disorders cases). In all LOSD cases (compared to age-matched normal controls), the frequencies of Lewy body disease (LBD), AGD, and corticobasal degeneration (CBD) were 26.1 % (11.3 %), 21.7 % (8.5 %), and 4.3 % (0.0 %), respectively. There was no case of pure Alzheimer's disease (AD). The total frequency of LBD, AGD, and CBD was significantly higher in LOSD cases than in normal controls. Argyrophilic grains were significantly more severe in LOSD than in controls, but were almost completely restricted to the limbic system and adjacent temporal cortex. In LOSD patients whose onset occurred at ≥65 years of age (versus age-matched normal controls), the frequencies of LBD and AGD were 36.4 % (19.4 %) and 36.4 % (8.3 %), respectively, and AGD was significantly more frequent in LOSD patients than in normal controls. In LOSD patients whose onset occurred at <65 years of age, the frequencies of LBD, AGD, and CBD were 16.7, 8.3, and 8.3 %, comparable to those of age-matched normal controls (10.2, 5.1, and 0.0 %). In all psychiatric cases, delusion was significantly more frequent in AGD cases than in cases bearing minimal AD pathology alone. Given these findings, LOSD patients may have heterogeneous pathological backgrounds, and AGD may be associated with the occurrence of LOSD especially after 65 years of age.

Case-control analysis of ambulance, emergency room, or inpatient hospital events for epilepsy and antiepileptic drug formulation changes.

PubMed

Zachry, Woodie M; Doan, Quynhchau D; Clewell, Jerry D; Smith, Brien J

2009-03-01

Although antiepileptic drugs (AEDs) with multisource generic alternatives are becoming more prevalent, no case-control studies have been published examining multisource medication use and epilepsy-related outcomes. This study evaluated the association between inpatient/emergency epilepsy care and the occurrence of a recent switch in AED formulation. A case-control analysis was conducted utilizing the Ingenix LabRx Database. Eligible patients were 12-64 years of age, received >or=145 days of AEDs in the preindex period, had continuous eligibility for 6 months preindex, and no prior inpatient/emergency care. Cases received care between 7/1/2006 and 12/31/2006 in an ambulance, emergency room, or inpatient hospital with a primary epilepsy diagnosis. Controls had a primary epilepsy diagnosis in a physician's office during the same period. The index date was the earliest occurrence of care in each respective setting. Cases and controls were matched 1:3 by epilepsy diagnosis and age. Odds of a switch between "A-rated" AEDs within 6 months prior to index were calculated. Cases (n = 416) had 81% greater odds of having had an A-rated AED formulation switch [odds ratio (OR) = 1.81; 95% confidence interval (CI) = 1.25 to 2.63] relative to controls (n = 1248). There were no significant differences between groups regarding demographics or diagnosis. Significant differences were found with regard to medical coverage type (case Medicaid = 4.6%, control Medicaid = 1.8%, p = 0.002). Post hoc analysis results excluding Medicaid recipients remained significant and concordant with the original analysis. This analysis found an association between patients receiving epilepsy care in an emergency or inpatient setting and the recent occurrence of AED formulation switching involving A-rated generics.

Comparative analysis of lactic acidosis induced by linezolid and vancomycin therapy using cohort and case-control studies of incidence and associated risk factors.

PubMed

Mori, Nobuaki; Kamimura, Yoshio; Kimura, Yuki; Hirose, Shoko; Aoki, Yasuko; Bito, Seiji

2018-04-01

Lactic acidosis is a rare complication of linezolid (LZD) therapy, and its incidence and risk factors remain unknown. This study aimed to compare the incidence of LZD-associated lactic acidosis (LALA) and vancomycin (VAN)-associated lactic acidosis (VALA) and investigate the risk factors for LALA. We performed a retrospective cohort study using propensity score-matched analyses comparing the incidence of lactic acidosis between LZD and VAN therapy. We included adult patients administered LZD or VAN between April 2014 and March 2016 and extracted patient baseline data. In a case-control study, we identified the risk factors of lactic acidosis in patients treated with LZD. We identified 94 and 313 patients who were administered LZD and VAN, respectively. The incidence of lactic acidosis after LZD and VAN therapy was 10.6 and 0.3%, respectively. After propensity score-matched analyses, the incidence of lactic acidosis with LZD therapy was significantly higher than that with VAN therapy [10.0% (8/80) vs. 0% (0/80), respectively; risk difference, 0.1; 95% confidence interval (CI), 0.03-0.17; p = 0.004]. In a case-control study, 10 patients with LALA were matched to 20 non-lactic acidosis patients by age and sex. Patients with LALA were more likely to have renal insufficiency than non-lactic acidosis patients that were in the univariate analysis (odds ratio, 7.4; 95% CI, 1.0-84.4; p = 0.02). This study indicates that LALA occurs more frequently than VALA does and is associated with renal insufficiency. Therefore, close monitoring of kidney function and serum lactate is recommended during LZD therapy.

Outcomes and prognostic factors for squamous cell carcinoma of the oral tongue in young adults: a single-institution case-matched analysis.

PubMed

Blanchard, Pierre; Belkhir, Farid; Temam, Stéphane; El Khoury, Clément; De Felice, Francesca; Casiraghi, Odile; Patrikidou, Anna; Mirghani, Haitham; Levy, Antonin; Even, Caroline; Gorphe, Philippe; Nguyen, France; Janot, François; Tao, Yungan

2017-03-01

There is controversy regarding prognosis and treatment of young patients with oral cavity cancer compared to their older counterparts. We conducted a retrospective case-matched analysis of all adult patients younger than 40 years and treated at our institution for a squamous cell carcinoma of the oral cavity. Only non-metastatic adult patients (age >18) with oral tongue cancer were eventually included and matched 1:1 with patients over 40 years of age, at least 20 years older than the cases, with same T and N category and treatment period. Sixty-three patients younger than 40 had an oral cavity squamous cell cancer out of which 57 had an oral tongue primary during the period 1999-2012, and 50 could be matched with an older control. No difference could be seen between younger and older patients with regard to overall, cancer-specific, or progression-free survival. The patterns of failure were similar, although in young patients, almost all failures occurred during the first 2 years following treatment. Although overall survival shows a trend toward lower survival in older patients, cancer-specific survival and analysis of pattern failure suggest that disease prognosis is similar between young and older adults with oral tongue cancer. Further work is needed to identify the younger patients with poorer prognosis who overwhelmingly fail during the first year after treatment and could benefit from treatment intensification. Until then, young adults ought to be treated using standard guidelines.

Tularemia Outbreak Investigation in Kosovo: Case Control and Environmental Studies

PubMed Central

Dedushaj, Isuf; Gjini, Ardiana; Jorgensen, Tine Rikke; Cotter, Benvon; Lieftucht, Alfons; D’Ancona, Fortunato; Dennis, David T.; Kosoy, Michael A.; Mulliqi-Osmani, Gjyle; Grunow, Roland; Kalaveshi, Ariana; Gashi, Luljeta; Humolli, Isme

2002-01-01

A large outbreak of tularemia occurred in Kosovo in the early postwar period, 1999-2000. Epidemiologic and environmental investigations were conducted to identify sources of infection, modes of transmission, and household risk factors. Case and control status was verified by enzyme-linked immunosorbent assay, Western blot, and microagglutination assay. A total of 327 serologically confirmed cases of tularemia pharyngitis and cervical lymphadenitis were identified in 21 of 29 Kosovo municipalities. Matched analysis of 46 case households and 76 control households suggested that infection was transmitted through contaminated food or water and that the source of infection was rodents. Environmental circumstances in war-torn Kosovo led to epizootic rodent tularemia and its spread to resettled rural populations living under circumstances of substandard housing, hygiene, and sanitation. PMID:11749751

A Structural Equation Modeling Analysis of Influences on Juvenile Delinquency

ERIC Educational Resources Information Center

Barrett, David E.; Katsiyannis, Antonis; Zhang, Dalun; Zhang, Dake

2014-01-01

This study examined influences on delinquency and recidivism using structural equation modeling. The sample comprised 199,204 individuals: 99,602 youth whose cases had been processed by the South Carolina Department of Juvenile Justice and a matched control group of 99,602 youth without juvenile records. Structural equation modeling for the…

Incremental cost effectiveness of proton pump inhibitors for the prevention of non-steroidal anti-inflammatory drug ulcers: a pharmacoeconomic analysis linked to a case-control study.

PubMed

Vonkeman, Harald E; Braakman-Jansen, Louise M A; Klok, Rogier M; Postma, Maarten J; Brouwers, Jacobus R B J; van de Laar, Mart A F J

2008-01-01

We estimated the cost effectiveness of concomitant proton pump inhibitors (PPIs) in relation to the occurrence of non-steroidal anti-inflammatory drug (NSAID) ulcer complications. This study was linked to a nested case-control study. Patients with NSAID ulcer complications were compared with matched controls. Only direct medical costs were reported. For the calculation of the incremental cost effectiveness ratio we extrapolated the data to 1,000 patients using concomitant PPIs and 1,000 patients not using PPIs for 1 year. Sensitivity analysis was performed by 'worst case' and 'best case' scenarios in which the 95% confidence interval (CI) of the odds ratio (OR) and the 95% CI of the cost estimate of a NSAID ulcer complication were varied. Costs of PPIs was varied separately. In all, 104 incident cases and 284 matched controls were identified from a cohort of 51,903 NSAID users with 10,402 NSAID exposition years. Use of PPIs was associated with an adjusted OR of 0.33 (95% CI 0.17 to 0.67; p = 0.002) for NSAID ulcer complications. In the extrapolation the estimated number of NSAID ulcer complications was 13.8 for non-PPI users and 3.6 for PPI users. The incremental total costs were euro 50,094 higher for concomitant PPIs use. The incremental cost effectiveness ratio was euro 4,907 per NSAID ulcer complication prevented when using the least costly PPIs. Concomitant use of PPIs for the prevention of NSAID ulcer complications costs euro 4,907 per NSAID ulcer complication prevented when using the least costly PPIs. The price of PPIs highly influenced the robustness of the results.

Risk of Psoriasis Following Terbinafine or Itraconazole Treatment for Onychomycosis: A Population-Based Case-Control Comparative Study.

PubMed

Chiu, Hsien-Yi; Chang, Wei-Lun; Tsai, Tsen-Fang; Tsai, Yi-Wen; Shiu, Ming-Neng

2018-03-01

Several case studies have reported an association between antifungal drug use and psoriasis risk. The objective of this study was to investigate the association between terbinafine/itraconazole exposure and psoriasis incidence. Among patients with onychomycosis in the Taiwan National Health Insurance Research Database, 3831 incident psoriasis cases were identified during 2004-2010 and compared with 3831 age- and sex-matched controls with the same look-back period. Multivariate conditional logistic regression was used for the analysis. The psoriasis cases were significantly more likely than matched controls to have used terbinafine or itraconazole (59.85 vs. 42.70%, respectively; p < 0.0001). After adjusting for potential confounders and cumulative duration of antifungal drug prescription, terbinafine/itraconazole use was associated with an increased psoriasis risk (adjusted odds ratio 1.33, 95% confidence interval 1.15-1.54). The association was stronger for more recent drug exposure (adjusted odds ratio 2.96, 95% confidence interval 2.25-3.90 for ≤ 90 days before the sampling date; adjusted odds ratio 1.04, 95% confidence interval 0.89-1.22 for > 360 days). In a comparison of patients receiving terbinafine or itraconazole only, psoriasis risk was higher for itraconazole (adjusted odds ratio 1.21, 95% confidence interval 1.05-1.40). This large population-based case-control analysis showed that exposure to terbinafine or itraconazole is associated with an increased risk of incident psoriasis. The finding of an increased psoriasis risk for antifungal drug users, particularly for itraconazole, deserves attention in clinical practice although further prospective studies are necessary to confirm our findings and clarify the biological mechanisms that underlie these associations.

Comparison of Well-being of Older Adult Choir Singers and the General Population in Finland: A Case-Control Study.

PubMed

Johnson, Julene K; Louhivuori, Jukka; Siljander, Eero

2017-06-01

Previous research suggests that singing in a choir as an older adult is associated with better quality of life (QOL). However, the degree to which sociodemographic variables and level of engagement in hobbies contribute to this relationship is largely unknown. The aim of the study was to compare quality of life (QOL) of older adult choir singers with a matched sample of older adults from the general population in Finland, taking into consideration sociodemographic, satisfaction with health, and level of engagement in hobbies (active, inactive). Case-control methods were used to match a sample of 109 older adult singers with a sample of 307 older adults from the general population. Tobit regression analysis with sociodemographic covariates was used to explore observed group differences in QOL as measured by two WHOQOL-Bref domains (psychological and physical). Probit regression analysis was used to examine the effect of sociodemographic variables and engagement in hobbies and on overall QOL and satisfaction with health. As expected, sociodemographic variables were strongly associated with physical and psychological QOL. After controlling for sociodemographic variables, the older choir singers reported significantly higher ratings on physical QOL, but not psychological QOL, compared to matched controls. Additional adjustment for satisfaction for health attenuated the results. When considering level of engagement in hobbies, older adult choir singers reported significantly higher overall QOL and satisfaction with health when compared to either controls who were either actively engaged in hobbies or not active in hobbies. These results suggest that singing in a choir as an older adult may promote well-being, even after accounting for sociodemographic and level of engagement in hobbies.

Comparison of Well-being of Older Adult Choir Singers and the General Population in Finland: A Case-Control Study

PubMed Central

Johnson, Julene K; Louhivuori, Jukka; Siljander, Eero

2017-01-01

Previous research suggests that singing in a choir as an older adult is associated with better quality of life (QOL). However, the degree to which sociodemographic variables and level of engagement in hobbies contribute to this relationship is largely unknown. The aim of the study was to compare quality of life (QOL) of older adult choir singers with a matched sample of older adults from the general population in Finland, taking into consideration sociodemographic, satisfaction with health, and level of engagement in hobbies (active, inactive). Case-control methods were used to match a sample of 109 older adult singers with a sample of 307 older adults from the general population. Tobit regression analysis with sociodemographic covariates was used to explore observed group differences in QOL as measured by two WHOQOL-Bref domains (psychological and physical). Probit regression analysis was used to examine the effect of sociodemographic variables and engagement in hobbies and on overall QOL and satisfaction with health. As expected, sociodemographic variables were strongly associated with physical and psychological QOL. After controlling for sociodemographic variables, the older choir singers reported significantly higher ratings on physical QOL, but not psychological QOL, compared to matched controls. Additional adjustment for satisfaction for health attenuated the results. When considering level of engagement in hobbies, older adult choir singers reported significantly higher overall QOL and satisfaction with health when compared to either controls who were either actively engaged in hobbies or not active in hobbies. These results suggest that singing in a choir as an older adult may promote well-being, even after accounting for sociodemographic and level of engagement in hobbies. PMID:28736492

Muscle Synergies May Improve Optimization Prediction of Knee Contact Forces During Walking

PubMed Central

Walter, Jonathan P.; Kinney, Allison L.; Banks, Scott A.; D'Lima, Darryl D.; Besier, Thor F.; Lloyd, David G.; Fregly, Benjamin J.

2014-01-01

The ability to predict patient-specific joint contact and muscle forces accurately could improve the treatment of walking-related disorders. Muscle synergy analysis, which decomposes a large number of muscle electromyographic (EMG) signals into a small number of synergy control signals, could reduce the dimensionality and thus redundancy of the muscle and contact force prediction process. This study investigated whether use of subject-specific synergy controls can improve optimization prediction of knee contact forces during walking. To generate the predictions, we performed mixed dynamic muscle force optimizations (i.e., inverse skeletal dynamics with forward muscle activation and contraction dynamics) using data collected from a subject implanted with a force-measuring knee replacement. Twelve optimization problems (three cases with four subcases each) that minimized the sum of squares of muscle excitations were formulated to investigate how synergy controls affect knee contact force predictions. The three cases were: (1) Calibrate+Match where muscle model parameter values were calibrated and experimental knee contact forces were simultaneously matched, (2) Precalibrate+Predict where experimental knee contact forces were predicted using precalibrated muscle model parameters values from the first case, and (3) Calibrate+Predict where muscle model parameter values were calibrated and experimental knee contact forces were simultaneously predicted, all while matching inverse dynamic loads at the hip, knee, and ankle. The four subcases used either 44 independent controls or five synergy controls with and without EMG shape tracking. For the Calibrate+Match case, all four subcases closely reproduced the measured medial and lateral knee contact forces (R2 ≥ 0.94, root-mean-square (RMS) error < 66 N), indicating sufficient model fidelity for contact force prediction. For the Precalibrate+Predict and Calibrate+Predict cases, synergy controls yielded better contact force predictions (0.61 < R2 < 0.90, 83 N < RMS error < 161 N) than did independent controls (-0.15 < R2 < 0.79, 124 N < RMS error < 343 N) for corresponding subcases. For independent controls, contact force predictions improved when precalibrated model parameter values or EMG shape tracking was used. For synergy controls, contact force predictions were relatively insensitive to how model parameter values were calibrated, while EMG shape tracking made lateral (but not medial) contact force predictions worse. For the subject and optimization cost function analyzed in this study, use of subject-specific synergy controls improved the accuracy of knee contact force predictions, especially for lateral contact force when EMG shape tracking was omitted, and reduced prediction sensitivity to uncertainties in muscle model parameter values. PMID:24402438

Muscle synergies may improve optimization prediction of knee contact forces during walking.

PubMed

Walter, Jonathan P; Kinney, Allison L; Banks, Scott A; D'Lima, Darryl D; Besier, Thor F; Lloyd, David G; Fregly, Benjamin J

2014-02-01

The ability to predict patient-specific joint contact and muscle forces accurately could improve the treatment of walking-related disorders. Muscle synergy analysis, which decomposes a large number of muscle electromyographic (EMG) signals into a small number of synergy control signals, could reduce the dimensionality and thus redundancy of the muscle and contact force prediction process. This study investigated whether use of subject-specific synergy controls can improve optimization prediction of knee contact forces during walking. To generate the predictions, we performed mixed dynamic muscle force optimizations (i.e., inverse skeletal dynamics with forward muscle activation and contraction dynamics) using data collected from a subject implanted with a force-measuring knee replacement. Twelve optimization problems (three cases with four subcases each) that minimized the sum of squares of muscle excitations were formulated to investigate how synergy controls affect knee contact force predictions. The three cases were: (1) Calibrate+Match where muscle model parameter values were calibrated and experimental knee contact forces were simultaneously matched, (2) Precalibrate+Predict where experimental knee contact forces were predicted using precalibrated muscle model parameters values from the first case, and (3) Calibrate+Predict where muscle model parameter values were calibrated and experimental knee contact forces were simultaneously predicted, all while matching inverse dynamic loads at the hip, knee, and ankle. The four subcases used either 44 independent controls or five synergy controls with and without EMG shape tracking. For the Calibrate+Match case, all four subcases closely reproduced the measured medial and lateral knee contact forces (R2 ≥ 0.94, root-mean-square (RMS) error < 66 N), indicating sufficient model fidelity for contact force prediction. For the Precalibrate+Predict and Calibrate+Predict cases, synergy controls yielded better contact force predictions (0.61 < R2 < 0.90, 83 N < RMS error < 161 N) than did independent controls (-0.15 < R2 < 0.79, 124 N < RMS error < 343 N) for corresponding subcases. For independent controls, contact force predictions improved when precalibrated model parameter values or EMG shape tracking was used. For synergy controls, contact force predictions were relatively insensitive to how model parameter values were calibrated, while EMG shape tracking made lateral (but not medial) contact force predictions worse. For the subject and optimization cost function analyzed in this study, use of subject-specific synergy controls improved the accuracy of knee contact force predictions, especially for lateral contact force when EMG shape tracking was omitted, and reduced prediction sensitivity to uncertainties in muscle model parameter values.

String Vessel Formation is Increased in the Brain of Parkinson Disease.

PubMed

Yang, Panzao; Pavlovic, Darja; Waldvogel, Henry; Dragunow, Mike; Synek, Beth; Turner, Clinton; Faull, Richard; Guan, Jian

2015-01-01

String vessels are collapsed basement membrane without endothelium and have no function in circulation. String vessel formation contributes to vascular degeneration in Alzheimer disease. By comparing to age-matched control cases we have recently reported endothelial degeneration in brain capillaries of human Parkinson disease (PD). Current study evaluated changes of basement membrane of capillaries, string vessel formation and their association with astrocytes, blood-brain-barrier integrity and neuronal degeneration in PD. Brain tissue from human cases of PD and age-matched controls was used. Immunohistochemical staining for collagen IV, GFAP, NeuN, tyrosine hydroxylase, fibrinogen and Factor VIII was evaluated by image analysis in the substantia nigra, caudate nucleus and middle frontal gyrus. While the basement-membrane-associated vessel density was similar between the two groups, the density of string vessels was significantly increased in the PD cases, particularly in the substantia nigra. Neuronal degeneration was found in all brain regions. Astrocytes and fibrinogen were increased in the caudate nuclei of PD cases compared with control cases. Endothelial degeneration and preservation of basement membrane result in an increase of string vessel formation in PD. The data may suggest a possible role for cerebral hypoperfusion in the neuronal degeneration characteristic of PD, which needs further investigation. Elevated astrocytosis in the caudate nucleus of PD cases could be associated with disruption of the blood-brain barrier in this brain region.

Case-control study of childhood acute lymphoblastic leukemia and residential radon exposure.

PubMed

Lubin, J H; Linet, M S; Boice, J D; Buckley, J; Conrath, S M; Hatch, E E; Kleinerman, R A; Tarone, R E; Wacholder, S; Robison, L L

1998-02-18

Several ecologic analyses have shown significant positive associations between mean indoor radon concentrations and risk of leukemia at all ages (acute myeloid leukemia and chronic lymphocytic leukemia) and for children (all leukemia, acute myeloid leukemia, and acute lymphoblastic leukemia [ALL]). As part of an age-matched, case-control study of childhood ALL in the United States, we investigated the association between the incidence of ALL in children under age 15 years and indoor radon exposure. Radon detectors were placed in current and previous homes of subjects where they resided for 6 months or longer. Children were included in analyses if radon measurements covered 70% or more of the 5-year period prior to diagnosis for case subjects (or from birth for case subjects under age 5 years) and the corresponding reference dates for control subjects. Radon levels could be estimated for 97% of the exposure period for the eligible 505 case subjects and 443 control subjects. Mean radon concentration was lower for case subjects (65.4 becquerels per cubic meter [Bqm(-3)]) than for control subjects (79.1 Bqm(-3)). For categories less than 37, 37-73, 74-147, and 148 or more Bqm(-3) of radon exposure, relative risks based on matched case-control pairs were 1.00, 1.22, 0.82, and 1.02, respectively, and were similar to results from an unmatched analysis. There was no association between ALL and radon exposure within subgroups defined by categories of age, income, birth order, birth weight, sex, type of residence, magnetic field exposure, parental age at the subject's birth, parental occupation, or parental smoking habits. In contrast to prior ecologic studies, the results from this analytic study provide no evidence for an association between indoor radon exposure and childhood ALL.

Clinically observed chickenpox and the risk of childhood-onset multiple sclerosis.

PubMed

Mikaeloff, Yann; Caridade, Guillaume; Suissa, Samy; Tardieu, Marc

2009-05-15

The authors conducted a population-based case-control study to investigate whether clinically observed chickenpox, linked with a level of intensity for clinical expression, increases the risk of multiple sclerosis (MS) in childhood. The cases were MS patients whose disease onset occurred between 1994 and 2003, before age 16 years, in France. Each case was matched for age, sex, and geographic origin with as many as 12 controls randomly selected from the general population. Information about clinically observed chickenpox in cases and controls before the index date regarding onset of MS was collected with a standardized questionnaire and was checked against health certificates. Conditional logistic regression was used to estimate the odds ratio for an association between MS and chickenpox. The 137 MS cases were matched with 1,061 controls. Clinically observed chickenpox had occurred in 76.6% of the cases and 84.9% of their matched controls. The adjusted odds ratio of MS onset associated with chickenpox occurrence was 0.58 (95% confidence interval: 0.36, 0.92). The authors concluded that clinically observed chickenpox was associated with a lower risk of childhood-onset MS in a French population.

Risk factors for oropharyngeal gonorrhoea in men who have sex with men: an age-matched case-control study.

PubMed

Cornelisse, Vincent J; Walker, Sandra; Phillips, Tiffany; Hocking, Jane S; Bradshaw, Catriona S; Lewis, David A; Prestage, Garrett Paul; Grulich, Andrew E; Fairley, Christopher K; Chow, Eric P F

2018-01-22

Oropharyngeal gonorrhoea is common among men who have sex with men (MSM). We aimed to clarify which oral sex practices were independent risk factors for oropharyngeal gonorrhoea: tongue kissing, receptive oro-penile sex (fellatio) or insertive oro-anal sex (rimming), and whether daily use of mouthwash and recent antibiotic use was protective. In 2015, we conducted an age-matched case-control study of MSM who attended the Melbourne Sexual Health Centre. Cases had tested positive for oropharyngeal gonorrhoea by nucleic acid amplification testing, and controls had tested negative. Questionnaire items included tongue kissing, oral sex practices, condom use, recent antibiotic use, mouthwash use and alcohol consumption. We identified 177 cases, age matched to 354 controls. In univariable analyses, cases were 1.90 times (95% CI 1.13 to 3.20) more likely than controls to have had casual sexual partners (CSP) in the preceding 3 months, were 2.17 times (95% CI 1.31 to 3.59) more likely to have kissed CSP and were 2.04 times (95% CI 1.26 to 3.30) more likely to have had receptive oro-penile sex with CSP. Oropharyngeal gonorrhoea was not associated with insertive oro-anal sex or mouthwash use. The number of CSP for tongue kissing and receptive oral sex and total CSP were highly correlated, and in multivariable analysis neither kissing nor receptive oro-penile sex was significantly associated with having oropharyngeal gonorrhoea, after adjusting for total number of CSP. The finding that oropharyngeal gonorrhoea was associated with a higher number of sexual partners but not specific sexual practices highlights the need for further research in the area of gonorrhoea transmission to define the probability of transmission from specific sex acts. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

The Economic Burden of Urinary Tract Infection and Pressure Ulceration in Acute Traumatic Spinal Cord Injury Admissions: Evidence for Comparative Economics and Decision Analytics from a Matched Case-Control Study.

PubMed

White, Barry A B; Dea, Nicolas; Street, John T; Cheng, Christiana L; Rivers, Carly S; Attabib, Najmedden; Kwon, Brian K; Fisher, Charles G; Dvorak, Marcel F

2017-10-15

Secondary complications of spinal cord injury (SCI) are a burden to affected individuals and the rest of society. There is limited evidence of the economic burden or cost of complications in SCI populations in Canada, however, which is necessary for comparative economic analyses and decision analytic modeling of possible solutions to these common health problems. Comparative economic analyses can inform resource allocation decisions, but the outputs are only as good as the inputs. In this article, new evidence of the excess or incremental costs of urinary tract infection (UTI) and pressure ulceration (PU) in acute traumatic SCI from an exploratory case series analysis of admissions to a Level I specialized Canadian spine facility (2008-2013) is presented. Participants in a national SCI registry were case-control matched (1:1) on the predicted probability of experiencing UTI or PU during initial acute SCI admission. The excess costs of UTI and PU are estimated as the mean of the differences in total direct acute SCI admission costs (length of stay, accommodation, nursing, pharmacy) from the perspective of the admitting facility between participants matched or paired on demographic and SCI characteristics. Even relatively minor UTI and PU, respectively, added an average of $7,790 (standard deviation [SD] $6,267) and $18,758 (SD $27,574) to the direct cost of acute SCI admission in 2013 Canadian dollars (CAD). This case series analysis established evidence of the excess costs of UTI and PU in acute SCI admissions, which will support decision-informing analyses in SCI.

Age-specific fluoride exposure in drinking water and osteosarcoma (United States).

PubMed

Bassin, Elise B; Wypij, David; Davis, Roger B; Mittleman, Murray A

2006-05-01

We explored age-specific and gender-specific effects of fluoride level in drinking water and the incidence of osteosarcoma. We used data from a matched case-control study conducted through 11 hospitals in the United States that included a complete residential history for each patient and type of drinking water (public, private well, bottled) used at each address. Our analysis was limited to cases less than 20 years old. We standardized fluoride exposure estimates based on CDC-recommended target levels that take climate into account. We categorized exposure into three groups (<30%, 30-99%, >99% of target) and used conditional logistic regression to estimate odds ratios. Analysis is based on 103 cases under the age of 20 and 215 matched controls. For males, the unadjusted odds ratios for higher exposures were greater than 1.0 at each exposure age, reaching a peak of 4.07 (95% CI 1.43, 11.56) at age 7 years for the highest exposure. Adjusting for potential confounders produced similar results with an adjusted odds ratio for males of 5.46 (95% CI 1.50, 19.90) at age 7 years. This association was not apparent among females. Our exploratory analysis found an association between fluoride exposure in drinking water during childhood and the incidence of osteosarcoma among males but not consistently among females. Further research is required to confirm or refute this observation.

Risk of intracerebral hemorrhage associated with phenprocoumon exposure: a nested case-control study in a large population-based German database.

PubMed

Behr, Sigrid; Andersohn, Frank; Garbe, Edeltraut

2010-07-01

Intracerebral hemorrhage (ICH) is the most serious complication of oral anticoagulation. This study investigated the risk of ICH for phenprocoumon which is the most widely used oral anticoagulant in Germany. We conducted a nested case-control study in a cohort of 13.4 million insurants of 4 German statutory health insurances (SHIs) who were continuously enrolled for 6 months prior to cohort entry. Cases were patients hospitalized for ICH. Ten controls were matched to each case by SHI, birth year, and sex using incidence density sampling. Rate ratios (RR) of ICH for current phenprocoumon use as compared to non-use were estimated from odds ratios calculated by conditional logistic regression analyses considering multiple risk factors. Analysis of the full cohort revealed a strong increase in incidence of ICH with increasing age. In the nested case-control study including 8138 cases of ICH and 81,373 matched controls, we observed an increased risk of ICH for current phenprocoumon exposure that varied with age. The phenprocoumon-associated risk of ICH was lower in older age groups with RRs from 4.20 (95% confidence interval (CI) 2.44-7.21) for phenprocoumon users less than 55 years of age to 2.43 (95%CI, 1.81-3.27) for those older than 85 years. Our study confirmed known risk factors of ICH. Phenprocoumon exposure was associated with an increased risk of ICH. The interaction of risk for phenprocoumon with age was unexpected and needs further study. (c) 2010 John Wiley & Sons, Ltd.

A case-control study of bladder cancer in the United States rubber and tyre industry.

PubMed

Checkoway, H; Smith, A H; McMichael, A J; Jones, F S; Monson, R R; Tyroler, H A

1981-08-01

A case-control study of bladder cancer was conducted in five United States rubber and tyre companies to determine if there were high-risk jobs and work areas within the industry. The study included 220 male cases of bladder cancer, of whom 107 were identified from hospital record reviews and 113 from death certificates. Each case was matched individually with two industry controls by sex, race, year of birth, and company. One control was matched additionally by year of hire and duration of employment. Comparisons of cases and controls not matched by year of hire and age of hire showed no differences for those variables, which suggests that age and calendar period of first exposure to the industry were not risk determinants. When the work histories of both cases and controls were contrasted it was found that cases were more likely than controls to have worked in milling (odds ratio (OR) = 1.91) and calender operation (OR = 2.21) jobs. The relative risk estimates for milling and calender operation both exhibited linear trends of increase with duration of exposure. Milling and calender operation jobs entail potential exposures to volatilised reaction products from heated rubber stock. A better understanding of aetiological associations with job type will require more detailed characterisation of the work environment with regard to the sources and levels of aromatic amines and other suspected bladder carcinogens.

A case-control study of bladder cancer in the United States rubber and tyre industry.

PubMed Central

Checkoway, H; Smith, A H; McMichael, A J; Jones, F S; Monson, R R; Tyroler, H A

1981-01-01

A case-control study of bladder cancer was conducted in five United States rubber and tyre companies to determine if there were high-risk jobs and work areas within the industry. The study included 220 male cases of bladder cancer, of whom 107 were identified from hospital record reviews and 113 from death certificates. Each case was matched individually with two industry controls by sex, race, year of birth, and company. One control was matched additionally by year of hire and duration of employment. Comparisons of cases and controls not matched by year of hire and age of hire showed no differences for those variables, which suggests that age and calendar period of first exposure to the industry were not risk determinants. When the work histories of both cases and controls were contrasted it was found that cases were more likely than controls to have worked in milling (odds ratio (OR) = 1.91) and calender operation (OR = 2.21) jobs. The relative risk estimates for milling and calender operation both exhibited linear trends of increase with duration of exposure. Milling and calender operation jobs entail potential exposures to volatilised reaction products from heated rubber stock. A better understanding of aetiological associations with job type will require more detailed characterisation of the work environment with regard to the sources and levels of aromatic amines and other suspected bladder carcinogens. PMID:7272236

Psychological disorders and oral lichen planus: matched case-control study and literature review.

PubMed

Pippi, R; Romeo, U; Santoro, M; Del Vecchio, A; Scully, C; Petti, S

2016-04-01

Oral lichen planus (OLP) may be linked to psychological disorders. This study investigated psychological factors associated with OLP. A case-control study with incident OLP case patients and age-gender-socio-economic status-matched controls, recruited from among relatives, accompanying persons, and departmental staff, investigated psychological traits using the Psychological General Well-Being Index-Short form. Common factor analysis was used to generate a set of psychological dimensions. The association between these dimensions and OLP adjusted for confounders (education, number of lifetime sexual partners, drinking-smoking) and interactions was assessed through conditional logistic regression and odds ratios (OR) were estimated. A total of 67 case-control pairs were recruited. Psychological dimensions generated were: dimension-1 (anxiety, low vitality), dimension-2 (negative well-being, low vitality), dimension-3 (depressed mood, low self-control). The ORs for OLP were, dimension-1, 1.0 (95% confidence interval -95CI, 0.3-2.6); dimension-2, 0.5 (95CI, 0.2-1.2); dimension-3, 4.8 (95CI, 1.8-12.9). Dimension-3 was highly associated with mild, but not associated with severe, OLP. Literature searching provided 21 studies, with anxiety and depression principally associated with OLP. Depressed mood and low self-control were highly associated with OLP, particularly the reticular-papular forms. These traits could have a causative role in OLP development-progression, but further investigations are necessary. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Increased Risk of Venous Thromboembolism in Women with Uterine Leiomyoma: A Nationwide, Population-Based Case-Control Study

PubMed Central

Huang, Hung-Kai; Kor, Chew-Teng; Chen, Ching-Pei; Chen, Hung-Te; Yang, Po-Ta; Tsai, Chen-Dao; Huang, Ching-Hui

2018-01-01

Background Venous thromboembolism (VTE) is a sex-specific disease that has different presentations between men and women. Women with uterine leiomyoma can present with VTE without exhibiting the traditional risk factors. We investigated the relationship between a history of uterine leiomyoma and the risk of VTE using the National Health Insurance Research Database (NHIRD). Methods We conducted a retrospective, nationwide, population-based case-control study using the NHIRD. We identified 2,282 patients with diagnosed VTE and 392,635 subjects without VTE from 2000 to 2013. After development of an age and index diagnosis year frequency-matched model and propensity score-matched model, 2 models with a case-to-control ratio of 1 to 4 were established. Using the diagnosis of uterine leiomyoma as the exposure factor, conditional logistic regression was performed to examine the association between uterine leiomyoma and VTE. Multiple logistic regression analysis was used to investigate the joint effect of uterine leiomyoma and comorbid diseases on the risk of VTE. Results A strong association was observed between uterine leiomyoma and VTE in the overall patient model, frequency-matched model and propensity score-matched model [p < 0.0001, odds ratio (OR): 1.547; p = 0.0005, OR: 1.486; p = 0.0405, OR: 1.26, respectively]. In the subgroup analyses, women with uterine leiomyoma who were ≥ 45 years old were less likely to experience VTE, but women with uterine leiomyoma and anemia, cancer, coronary artery disease or heart failure were more likely to experience VTE. Conclusions Women with uterine leiomyomas have an increased risk of developing VTE, especially during reproductive periods or in the presence of specific diseases. PMID:29375226

Better cancer biomarker discovery through better study design.

PubMed

Rundle, Andrew; Ahsan, Habibul; Vineis, Paolo

2012-12-01

High-throughput laboratory technologies coupled with sophisticated bioinformatics algorithms have tremendous potential for discovering novel biomarkers, or profiles of biomarkers, that could serve as predictors of disease risk, response to treatment or prognosis. We discuss methodological issues in wedding high-throughput approaches for biomarker discovery with the case-control study designs typically used in biomarker discovery studies, especially focusing on nested case-control designs. We review principles for nested case-control study design in relation to biomarker discovery studies and describe how the efficiency of biomarker discovery can be effected by study design choices. We develop a simulated prostate cancer cohort data set and a series of biomarker discovery case-control studies nested within the cohort to illustrate how study design choices can influence biomarker discovery process. Common elements of nested case-control design, incidence density sampling and matching of controls to cases are not typically factored correctly into biomarker discovery analyses, inducing bias in the discovery process. We illustrate how incidence density sampling and matching of controls to cases reduce the apparent specificity of truly valid biomarkers 'discovered' in a nested case-control study. We also propose and demonstrate a new case-control matching protocol, we call 'antimatching', that improves the efficiency of biomarker discovery studies. For a valid, but as yet undiscovered, biomarker(s) disjunctions between correctly designed epidemiologic studies and the practice of biomarker discovery reduce the likelihood that true biomarker(s) will be discovered and increases the false-positive discovery rate. © 2012 The Authors. European Journal of Clinical Investigation © 2012 Stichting European Society for Clinical Investigation Journal Foundation.

Babies and bearded dragons: sudden increase in reptile-associated Salmonella enterica serovar Tennessee infections, Germany 2008.

PubMed

Weiss, Bettina; Rabsch, Wolfgang; Prager, Rita; Tietze, Erhard; Koch, Judith; Mutschmann, Frank; Roggentin, Peter; Frank, Christina

2011-09-01

In 2008 a marked increase in Salmonella enterica serovar Tennessee infections in infants occurred in Germany. In March and April 2008, eight cases were notified compared to a median of 0-1 cases in 2001-2006. We carried out an investigation including a case-control study to identify the source of infection. A patient was a child < 3 years of age with Salmonella Tennessee isolated from stool from September 1, 2007, through December 31, 2008, identified through the national surveillance system. A control was a child with a notified rotavirus infection in the matching district, frequency matched by age group. We conducted telephone interviews on feeding, herbal infusions, and animal contact. Matched odds ratios (mOR) were calculated using exact conditional logistic regression. For Salmonella Tennessee isolates, pulsed-field gel electrophoresis and multiple-locus variable number tandem repeat analysis were performed. Further cloacal swab samples of reptiles kept in case households were investigated. We identified 18 cases < 3 years. Ten children were male; median age was 3 months (1-32 months). In 8 of 16 case households reptiles were kept. Direct contact between child and reptile was denied. Other forms of reptile contact were reported in four of the remaining eight households. Ten case- and 21 control-patients were included in the study. Only keeping of a reptile and "any reptile contact" were associated with Salmonella Tennessee infection (mOR 29.0; 95% CI 3.1 ± ∞ and mOR 119.5; 95% CI 11.7 - ∞). Identical Salmonella Tennessee strains of child and reptile kept in the same household could be shown in 2 cases. Reptiles were the apparent source of Salmonella Tennessee infection in these infants. Indirect contact between infants and reptiles seems to be sufficient to cause infection and should therefore be avoided.

Iodine 125 Brachytherapy With Vitrectomy and Silicone Oil in the Treatment of Uveal Melanoma: 1-to-1 Matched Case-Control Series

DOE Office of Scientific and Technical Information (OSTI.GOV)

McCannel, Tara A., E-mail: TMcCannel@jsei.ucla.edu; McCannel, Colin A.

Purpose: We initially reported the radiation-attenuating effect of silicone oil 1000 centistokes for iodine 125. The purpose of this report was to compare the clinical outcomes in case patients who had iodine 125 brachytherapy with vitrectomy and silicone oil 1000 centistokes with the outcomes in matched control patients who underwent brachytherapy alone. Methods and Materials: Consecutive patients with uveal melanoma who were treated with iodine 125 plaque brachytherapy and vitrectomy with silicone oil with minimum 1-year follow-up were included. Control patients who underwent brachytherapy alone were matched for tumor size, location, and sex. Baseline patient and tumor characteristics and tumor response tomore » radiation, final visual acuity, macular status, central macular thickness by ocular coherence tomography (OCT), cataract progression, and metastasis at last follow-up visit were compared. Surgical complications were also determined. Results: Twenty case patients met the inclusion criteria. The average follow-up time was 22.1 months in case patients and 19.4 months in control patients. The final logMAR vision was 0.81 in case patients and 1.1 in control patients (P=.071); 8 case patients and 16 control patients had abnormal macular findings (P=.011); and the average central macular thickness by OCT was 293.2 μm in case patients and 408.5 μm in control patients (P=.016). Eleven case patients (55%) and 1 control patient (5%) had required cataract surgery at last follow-up (P=.002). Four patients in the case group and 1 patient in the control group experienced metastasis (P=.18). Among the cases, intraoperative retinal tear occurred in 3 patients; total serous retinal detachment and macular hole developed in 1 case patient each. There was no case of rhegmatogenous retinal detachment, treatment failure, or local tumor dissemination in case patients or control patients. Conclusions: With up to 3 years of clinical follow-up, silicone oil during brachytherapy for the treatment of uveal melanoma resulted in fewer abnormal maculas, lower central macular thickness on OCT, and a trend toward better final visual acuity in comparison with matched control patients who underwent brachytherapy alone.« less

Risk factors for the development of colorectal carcinoma: A case control study from South India

PubMed Central

Iswarya, Santhana Krishnan; Premarajan, Kariyarath Cheriyath; Kar, Sitanshu Sekhar; Kumar, Sathasivam Suresh; Kate, Vikram

2016-01-01

AIM: To study the association of colorectal carcinoma (CRC) with diet, smoking, alcohol, physical activity, body mass index, family history and diabetes. METHODS: All consecutive patients with CRC confirmed by histopathology diagnosis were included. Age (± 5 years) and gender matched controls were selected among the patients admitted in surgery ward for various conditions without any co-existing malignancy. Food frequency questionnaire (FFQ) was developed and validated after pretesting by investigator trained in data collection techniques. Cases and controls were interviewed ensuring privacy, in similar interview setting, with same duration of time for both cases and controls without any leading question. Biological variables like family history of CRC in first degree relatives, history of diabetes mellitus; behavioral factors like tobacco use both smoking and smokeless form, alcohol consumption and physical activity were recorded. Dietary details were recorded using a FFQ consisting 29 food items with seven categories. Analysis was done using appropriate statistical methods. RESULTS: Ninety-four histopathologically confirmed cases of CRC and equal number of age and gender matched controls treated over a period of two years were studied. Age distribution, mean age, male to female ratio, education level and socioeconomic status were similar in cases and controls. Intake of food items was categorized into tertile due to skewed distribution of subjects as per recommended cut off for consumption of food item. On univariate analysis red meat [OR = 7.4 (2.935-18.732)], egg [OR = 5.1 (2.26-11.36)], fish, fried food and oil consumption were found to be risk factors for CRC. On multivariate analysis red meat consumption of more than 2-3 times a month (OR = 5.4; 95%CI: 1.55-19.05) and egg consumption of more than 2-3 times a week (OR = 3.67; 95%CI: 1.23-9.35) were found to be independent risk factors for the development of CRC. CONCLUSION: Egg and red meat consumption found to be independent risk factors for CRC. Smoking, alcohol, physical activity and family history were not associated with increased risk. PMID:26909135

Statin Use and Fatal Prostate Cancer: A Matched Case-Control Study

PubMed Central

Marcella, Stephen W.; David, Alice; Ohman-Strickland, Pamela A.; Carson, Jeffery; Rhoads, George G.

2015-01-01

Background Statins are one of the most commonly prescribed medications in medical practice and prostate cancer is the most common male malignancy. While there has been no consistent evidence that statins affect cancer incidence, including prostate cancer, several reports suggest they may decrease the rate of advanced prostate cancer. However, no study has examined statin use and prostate cancer mortality specifically. We report here a population-based case-control investigation that examines this association. Methods We conducted a matched case-control study. Cases were residents of New Jersey ages 55 – 79 who died from prostate cancer between 1997–2000. We individually matched population-based controls by five-year age-group and race. Medication data were obtained identically for cases and controls from blinded medical chart review. We used conditional logistic regression to adjust for confounders. Results We identified 718 cases and obtained cooperation from 77% of their spouses (N=553). After review of medical records, 387 were eligible and 380 were matched to a control. The unadjusted odds ratio was 0.49 (95% CI, 0.34–0.70) which decreased to 0.37 (p<0.0001) after adjustment for education, waist size, BMI, comorbidities, and anti-hypertensive medication. There was little difference between lipophilic and hydrophilic statins but more risk reduction was noted for hi-potency statins (73%, p<0.0001) as compared to low-potency statins (31%, p=0.32). Conclusion Statin use is associated with substantial protection against prostate cancer death, adding to the epidemiologic evidence for an inhibitory effect on prostate cancer. PMID:22180145

Dietary and other risk factors in the aetiology of cholelithiasis: a case control study.

PubMed

Linos, A D; Daras, V; Linos, D A; Kekis, V; Tsoukas, M M; Golematis, V

1989-10-01

We studied the effect of dietary factors and a variety of other risk factors on the development of cholelithiasis through a case control study. The study involved 96 cases and 118 age and sex matched controls. All cases and controls were interviewed with regard to a variety of risk factors and frequency of consumption of over 100 food items. Analysis was done both by chi square and a multiple logistic regression model. From all the dietary factors the only ones that showed a positive statistically significantly (p less than 0.05) association was consumption of animal fat as expressed by eating all visible fat on the meat and using butter on the table. Interestingly high consumption of olive oil had a negative (protective) association with the disease. A negative association was also found with smoking and holding a job demanding hard labor.

A case control study of senile cataract in a hospital based population.

PubMed

Badrinath, S S; Sharma, T; Biswas, J; Srinivas, V

1996-12-01

A case-control study (244 cases and 264 controls) was done during 1986-89 on a hospital based population to evaluate the risk factors associated with the etiology of senile cataract. Patient with age between 40-60 years, visual acuity of 6/9 or less, and presence of lenticular opacity of senile origin were included as cases. Age matched individuals with absence of lenticular opacity made up the controls. Multivariate logistic regression analysis revealed that higher systolic BP and number of meals were significantly (P < or = 0.05) associated with presence of senile cataract; whereas higher weight, education and income, and utilization of cooking water had a significant protective effect against senile cataract. The present study helps the clinician to understand the possible risk factors associated with the development of senile cataract and could be helpful in designing a intervention strategy in future.

Dietary and Other Risk Factors in The Aetiology of Cholelithiasis: A Case Control Study

PubMed Central

Daras, V.; Linos, D. A.; Kekis, V.; Tsoukas, M. M.; Golematis, V.

1989-01-01

We studied the effect of dietary factors and a variety of other risk factors on the development of cholelithiasis through a case control study. The study involved 96 cases and 118 age and sex matched controls. All cases and controls were interviewed with regard to a variety of risk factors and frequency of consumption of over 100 food items. Analysis was done both by chi square and a multiple logistic regression model. From all the dietry factors the only ones that showed a positive statistically signficantly (p<0.05) association was consumption of animal fat as expressed by eating all visible fat on the meat and using butter on the table. Interestingly high consumption of olive oil had a negative (protective) association with the disease. A negative association was also found with smoking and holding a job demanding hard labor. PMID:2487388

Packed red blood cell transfusion is not associated with increased risk of necrotizing enterocolitis in premature infants

PubMed Central

Sharma, R; Kraemer, DF; Torrazza, RM; Mai, V; Neu, J; Shuster, JJ; Hudak, ML

2015-01-01

OBJECTIVE Recent reports have posited a temporal association between blood transfusion with packed red blood cells (BT) and necrotizing enterocolitis (NEC). We evaluated the relationship between BT and NEC among infants at three hospitals who were consented at birth into a prospective observational study of NEC. STUDY DESIGN We used a case–control design to match each case of NEC in our study population of infants born at <33 weeks postmenstrual age (PMA) to one control infant using hospital of birth, PMA, birth weight and date of birth. RESULT The number of transfusions per infant did not differ between 42 NEC cases and their controls (4.0 ± 4.6 vs 5.4 ± 4.1, mean ± s.d., P = 0.063). A matched-pair analysis did not identify an association of transfusion with NEC in either the 48-h or 7-day time periods before the onset of NEC. Stratifying on matched-sets, the Cox proportional hazard model did not identify any difference in the total number of BTs between the two groups (hazard ratio 0.78, 95% confidence interval 0.57 to 1.07, P = 0.11). CONCLUSION In contrast to previous studies, our case–control study did not identify a significant temporal association between BT and NEC. Additional large prospective randomized studies are needed to clarify the relationship between BT and NEC. PMID:25144159

The impact of hospital-onset Clostridium difficile infection on outcomes of hospitalized patients with sepsis.

PubMed

Lagu, Tara; Stefan, Mihaela S; Haessler, Sarah; Higgins, Thomas L; Rothberg, Michael B; Nathanson, Brian H; Hannon, Nicholas S; Steingrub, Jay S; Lindenauer, Peter K

2014-07-01

To examine the impact of hospital-onset Clostridium difficile infection (HOCDI) on the outcomes of patients with sepsis. Most prior studies that have addressed this issue lacked adequate matching to controls, suffered from small sample size, or failed to consider time to infection. Retrospective cohort study. We identified adults with a principal or secondary diagnosis of sepsis who received care at 1 of the institutions that participated in a large multihospital database between July 1, 2004 and December 31, 2010. Among eligible patients with sepsis, we identified patients who developed HOCDI during their hospital stay. We used propensity matching and date of diagnosis to match cases to patients without Clostridium difficile infections and compared outcomes between the 2 groups. Of 218,915 sepsis patients, 2368 (1.08%) developed HOCDI. Unadjusted in-hospital mortality was significantly higher in HOCDI patients than controls (25% vs 10%, P < 0.001). After multivariate adjustment, in-hospital mortality rate was 24% in cases vs. 15% in controls. In an analysis limited to survivors, adjusted length of stay (LOS) among cases with Clostridium difficile infections was 5.1 days longer than controls (95% confidence interval: 4.4-5.8) and the median-adjusted cost increase was $4916 (P < 0.001). After rigorous adjustment for time to diagnosis and presenting severity, hospital-acquired Clostridium difficile infection was associated with increased mortality, LOS, and cost. Our results can be used to assess the cost-effectiveness of prevention programs and suggest that efforts directed toward high-risk patient populations are needed. © 2014 Society of Hospital Medicine.

Characterization of dermatitis after PD-1/PD-L1 inhibitor therapy and association with multiple oncologic outcomes: a retrospective case-control study.

PubMed

Min Lee, Charles Kyung; Li, Shufeng; Tran, Duy Cong; Zhu, Gefei Alex; Kim, Jinah; Kwong, Bernice Y; Chang, Anne Lynn S

2018-05-29

Cutaneous adverse events are common with Programmed Death (PD)-1/ PD-Ligand (L)1 inhibitors. However, the nature of the specific cutaneous adverse event of dermatitis has not been investigated across various PD-1/PD-L1 inhibitors. Oncologic outcomes potentially associated with dermatitis are not well characterized. (s): To assess the nature of dermatitis after PD-1/PD-L1 inhibitor exposure and oncologic outcomes associated with dermatitis. Retrospective, matched, case-control study conducted at a single academic center. The most common histologic patterns were lichenoid dermatitis (50%) and spongiotic dermatitis (40%). Overall tumor response rate was 65.0% for cases and 17.0% for controls (p=0.0007), odds ratio: 7.3 (95% CI 2.3-23.1). Progression Free Survival (PFS) and Overall Survival (OS) times were significantly longer for cases than controls by Kaplan-Meier analysis (p<0.0001 and 0.0203, respectively). Retrospective design and relatively small sample size precluded matching on all cancer types. Lichenoid and spongiotic dermatitis associated with PD-1/PD-L1 inhibitors could be a sign of robust immune response and improved oncologic outcomes. The predictive value of PD-1/PD-L1 related dermatitis on cancer outcomes awaits investigation through prospective multicenter studies for specific cancer types. Copyright © 2018. Published by Elsevier Inc.

Clinical and treatment-related risk factors for nosocomial colonisation with extensively drug-resistant Pseudomonas aeruginosa in a haematological patient population: a matched case control study.

PubMed

Willmann, Matthias; Klimek, Anna M; Vogel, Wichard; Liese, Jan; Marschal, Matthias; Autenrieth, Ingo B; Peter, Silke; Buhl, Michael

2014-12-10

This study aimed to investigate risk factors for colonisation with extensively drug-resistant P. aeruginosa (XDR-PA) in immunocompromised patients and to build a clinical risk score (CRS) based on these results. We conducted a matched case-control study with 31 cases and 93 controls (1:3). Cases were colonised with XDR-PA during hospitalisation. Independent risk factors were determined using a three step conditional logistic regression procedure. A CRS was built with respect to the corresponding risk fraction of each risk factor, and its discriminatory power was estimated by receiver operating characteristic (ROC) analysis. The presence of a central venous catheter (OR 7.41, P = 0.0008), the presence of a urinary catheter (OR 21.04, P < 0.0001), CRP > 10 mg/dl (OR 7.36, P = 0.0015), and ciprofloxacin administration (OR 5.53, P = 0.025) were independent risk factors. The CRS exhibited a high discriminatory power, defining a high risk population with an approximately fourteen times greater risk for XDR-PA colonisation. Unnecessary use of antibiotics, particularly ciprofloxacin should be avoided, and a high standard of infection control measures must be achieved when using medical devices. A CRS can be used for adaptation of the active screening culture policy to the local setting.

A Case-Control Study to Identify Risk Factors Associated with Avian Influenza Subtype H9N2 on Commercial Poultry Farms in Pakistan

PubMed Central

Chaudhry, Mamoona; Rashid, Hamad B.; Thrusfield, Michael; Welburn, Sue; Bronsvoort, Barend MdeC.

2015-01-01

A 1:1 matched case-control study was conducted to identify risk factors for avian influenza subtype H9N2 infection on commercial poultry farms in 16 districts of Punjab, and 1 administrative unit of Pakistan. One hundred and thirty-three laboratory confirmed positive case farms were matched on the date of sample submission with 133 negative control farms. The association between a series of farm-level characteristics and the presence or absence of H9N2 was assessed by univariable analysis. Characteristics associated with H9N2 risk that passed the initial screening were included in a multivariable conditional logistic regression model. Manual and automated approaches were used, which produced similar models. Key risk factors from all approaches included selling of eggs/birds directly to live bird retail stalls, being near case/infected farms, a previous history of infectious bursal disease (IBD) on the farm and having cover on the water storage tanks. The findings of current study are in line with results of many other studies conducted in various countries to identify similar risk factors for AI subtype H9N2 infection. Enhancing protective measures and controlling risks identified in this study could reduce spread of AI subtype H9N2 and other AI viruses between poultry farms in Pakistan. PMID:25774768

Sarcoidosis diagnosed after September 11, 2001, among adults exposed to the World Trade Center disaster.

PubMed

Jordan, Hannah T; Stellman, Steven D; Prezant, David; Teirstein, Alvin; Osahan, Sukhminder S; Cone, James E

2011-09-01

Explore relationships between World Trade Center (WTC) exposures and sarcoidosis. Sarcoidosis has been reported after exposure to the WTC disaster. We ascertained biopsy-proven post-9/11 sarcoidosis among WTC Health Registry enrollees. Cases diagnosed after Registry enrollment were included in a nested case-control study. Controls were matched to cases on age, sex, race or ethnicity, and eligibility group (eg, rescue or recovery worker). We identified 43 cases of post-9/11 sarcoidosis. Twenty-eight incident cases and 109 controls were included in the case-control analysis. Working on the WTC debris pile was associated with sarcoidosis (odds ratio 9.1, 95% confidence interval 1.1 to 74.0), but WTC dust cloud exposure was not (odds ratio 1.0, 95% confidence interval 0.4 to 2.8). Working on the WTC debris pile was associated with an elevated risk of post-9/11 sarcoidosis. Occupationally exposed workers may be at increased risk. (C)2011The American College of Occupational and Environmental Medicine

Statin use and fatal prostate cancer: a matched case-control study.

PubMed

Marcella, Stephen W; David, Alice; Ohman-Strickland, Pamela A; Carson, Jeffery; Rhoads, George G

2012-08-15

Statins are some of the most commonly prescribed medications in medical practice, and prostate cancer is the most common malignancy among men. Although there has been no consistent evidence that statins affect cancer incidence, including prostate cancer, several reports suggest they may decrease the rate of advanced prostate cancer. However, no study to date has specifically examined statin use and prostate cancer mortality. The authors conducted this population-based case-control investigation to examine this association. This was a matched case-control study. Cases were residents of New Jersey ages 55 to 79 years who died from prostate cancer between 1997 and 2000. The cases were matched individually to population-based controls by 5-year age group and race. Medication data were obtained identically for cases and controls from blinded medical chart review. Conditional logistic regression was used to adjust for confounders. In total, 718 cases were identified, and cooperation was obtained from 77% of their spouses (N = 553). After a review of medical records, 387 men were eligible, and 380 were matched to a control. The unadjusted odds ratio was 0.49 (95% confidence interval, 0.34-0.70) and decreased to 0.37 (P < .0001) after adjusting for education, waist size, body mass index, comorbidities, and antihypertensive medication. There was little difference between lipophilic and hydrophilic statins, but more risk reduction was noted for high-potency statins (73%; P < .0001) compared with low-potency statins (31%; P = .32). Statin use was associated with substantial protection against prostate cancer death, adding to the epidemiologic evidence for an inhibitory effect on prostate cancer. Copyright © 2011 American Cancer Society.

Risk factors for non-syndromic oral clefts: a matched case-control study in Hubei Province, China.

PubMed

Qi, L; Liu, J; Zhang, Y; Wang, J; Yang, M; Gong, T; Shen, M; Du, Y

2015-01-01

To explore the risk factors for CL/P in Hubei Province, China. A hospital-based, matched case-control study was conducted. One hundred and eight cases with CL/P were matched by age and sex with 108 normal controls. Their parents were retrospectively interviewed using a questionnaire. Univariate and multivariate analyses were used to calculate the relative risk by odds ratio and 95% confidence interval. Univariate analysis identified ten factors as significantly related to CL/P (P < 0.05). Multivariate conditional logistic regression models showed that five of these factors were significantly associated with CL/P. Paternal occupational exposure (OR = 13.08, 95% CI: 2.35-72.86), first-trimester maternal illness (OR = 36.67, 95% CI: 5.37-250.36), first-trimester maternal bad mood (OR = 8.69, 95% CI: 1.35-55.84), first-trimester maternal diet of eggs or milk (≥5 meals per week, OR = 6.72, 95% CI: 1.23-36.69), and first-trimester maternal sexual activity (OR = 5.98, CI 95%:1.14-31.49) were risk factors for CL/P. In our study, we identified that paternal occupational exposure, first-trimester maternal illness, first-trimester maternal bad mood, first-trimester maternal diet of eggs or milk (≥5 meals per week), and first-trimester maternal sexual activities were significantly associated with increased CL/P. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

High incidence of non-tuberculous mycobacteria-positive cultures among adolescent with cystic fibrosis.

PubMed

Cavalli, Zoé; Reynaud, Quitterie; Bricca, Romain; Nove-Josserand, Raphaële; Durupt, Stéphane; Reix, Philippe; Perceval, Marie; de Montclos, Michèle Pérouse; Lina, Gérard; Durieu, Isabelle

2017-09-01

We evaluated the prevalence of non-tuberculous mycobacteria (NTM)-positive cultures among our cystic fibrosis (CF) center patients, reviewed risk factors for NTM positivity, and determined its impact on lung function evolution. From 2009 to 2014, CF adults and children attending the CF center of Lyon (France) and having at least one positive NTM isolate were included. Each case was matched by age and gender with two CF patients with no NTM isolate (controls). 48 CF patients with NTM-positive isolates were matched to 96 controls. The age group for whom incident NTM was higher was young adolescents aged 13 to 17. A significant association for NTM positivity was found with Staphylococcusaureus in multivariate analysis and with allergic bronchopulmonary aspergillosis, corticosteroid and itraconazole in univariate analysis. Mean annual FEV1 decline was faster for NTM-positive patients compared to controls. These data highlight the high incidence of NTM-positive cultures among young adolescents with CF. Copyright © 2017 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.

Patterns of Somatic Diagnoses in Older People with Intellectual Disability: A Swedish Eleven Year Case-Control Study of Inpatient Data

ERIC Educational Resources Information Center

Sandberg, Magnus; Ahlström, Gerd; Kristensson, Jimmie

2017-01-01

Background: Knowledge about diagnoses patterns in older people with intellectual disabilities is limited. Methods: The case group (n = 7936) comprised people with intellectual disabilities aged 55 years and older. The control group (n = 7936) was age matched and sex matched. Somatic inpatient diagnoses (2002-2012) were collected retrospectively.…

Pilot case-control study of paediatric falls from windows.

PubMed

Johnston, Brian D; Quistberg, D Alexander; Shandro, Jamie R; Partridge, Rebecca L; Song, Hyun Rae; Ebel, Beth E

2011-12-01

Unintentional falls from windows are an important cause of paediatric morbidity. There have been no controlled studies to identify modifiable environmental risk factors for window falls in young children. The authors have piloted a case-control study to test procedures for case identification, subject enrolment, and environmental data collection. Case windows were identified when a child 0-9 years old presented for care after a fall from that window. Control windows were identified (1) from the child's home and (2) from the home of an age- and gender-matched child seeking care for an injury diagnosis not related to a window fall. Study staff visited enrolled homes to collect window measurements and conduct window screen performance tests. The authors enrolled and collected data on 18 case windows, 18 in-home controls, and 14 matched community controls. Six potential community controls were contacted for every one enrolled. Families who completed the home visit viewed study procedures positively. Case windows were more likely than community controls to be horizontal sliders (100% vs 50%), to have deeper sills (6.28 vs 4.31 inches), to be higher above the exterior surface (183 vs 82 inches), and to have screens that failed below a threshold derived from the static pressure of a 3-year-old leaning against the mesh (60.0% vs 16.7%). Case windows varied very little from in-home controls. Case-control methodology can be used to study risk factors for paediatric falls from windows. Recruitment of community controls is challenging but essential, because in-home controls tend to be over-matched on important variables. A home visit allows direct measurement of window type, height, sill depth, and screen performance. These variables should all be investigated in subsequent, larger studies covering major housing markets.

A three-dimensional soft tissue analysis of Class III malocclusion: a case-controlled cross-sectional study.

PubMed

Johal, Ama; Chaggar, Amrit; Zou, Li Fong

2018-03-01

The present study used the optical surface laser scanning technique to compare the facial features of patients aged 8-18 years presenting with Class I and Class III incisor relationship in a case-control design. Subjects with a Class III incisor relationship, aged 8-18 years, were age and gender matched with Class I control and underwent a 3-dimensional (3-D) optical surface scan of the facial soft tissues. Landmark analysis revealed Class III subjects displayed greater mean dimensions compared to the control group most notably between the ages of 8-10 and 17-18 years in both males and females, in respect of antero-posterior (P = 0.01) and vertical (P = 0.006) facial dimensions. Surface-based analysis, revealed the greatest difference in the lower facial region, followed by the mid-face, whilst the upper face remained fairly consistent. Significant detectable differences were found in the surface facial features of developing Class III subjects.

Possible association of first and high birth order of pregnant women with the risk of isolated congenital abnormalities in Hungary - a population-based case-matched control study.

PubMed

Csermely, Gyula; Susánszky, Éva; Czeizel, Andrew E; Veszprémi, Béla

2014-08-01

In epidemiological studies at the estimation of risk factors in the origin of specified congenital abnormalities in general birth order (parity) is considered as confounder. The aim of this study was to analyze the possible association of first and high (four or more) birth order with the risk of congenital abnormalities in a population-based case-matched control data set. The large dataset of the Hungarian Case-Control Surveillance of Congenital Abnormalities included 21,494 cases with different isolated congenital abnormality and their 34,311 matched controls. First the distribution of birth order was compared of 24 congenital abnormality groups and their matched controls. In the second step the possible association of first and high birth order with the risk of congenital abnormalities was estimated. Finally some subgroups of neural-tube defects, congenital heart defects and abdominal wall's defects were evaluated separately. A higher risk of spina bifida aperta/cystica, esophageal atresia/stenosis and clubfoot was observed in the offspring of primiparous mothers. Of 24 congenital abnormality groups, 14 had mothers with larger proportion of high birth order. Ear defects, congenital heart defects, cleft lip± palate and obstructive defects of urinary tract had a linear trend from a lower proportion of first born cases to the larger proportion of high birth order. Birth order showed U-shaped distribution of neural-tube defects and clubfoot, i.e. both first and high birth order had a larger proportion in cases than in their matched controls. Birth order is a contributing factor in the origin of some isolated congenital abnormalities. The higher risk of certain congenital abnormalities in pregnant women with first or high birth order is worth considering in the clinical practice, e.g. ultrasound scanning. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Systematic review and meta-analysis estimating association of cysticercosis and neurocysticercosis with epilepsy.

PubMed

Debacq, Gabrielle; Moyano, Luz M; Garcia, Héctor H; Boumediene, Farid; Marin, Benoit; Ngoungou, Edgard B; Preux, Pierre-Marie

2017-03-01

We reviewed studies that analyzed cysticercosis (CC), neurocysticercosis (NCC) and epilepsy across Latin America, Asia and Sub-Saharan Africa, to estimate the odds ratio and etiologic fraction of epilepsy due to CC in tropical regions. We conducted a systematic review of the literature on cysticercosis and epilepsy in the tropics, collecting data from case-control and cross-sectional studies. Exposure criteria for CC included one or more of the following: serum ELISA or EITB positivity, presence of subcutaneous cysts (both not verified and unverified by histology), histology consistent with calcified cysts, and brain CT scan consistent with NCC. A common odds-ratio was then estimated using meta-analysis. 37 studies from 23 countries were included (n = 24,646 subjects, 14,934 with epilepsy and 9,712 without epilepsy). Of these, 29 were case-control (14 matched). The association between CC and epilepsy was significant in 19 scientific articles. Odds ratios ranged from 0.2 to 25.4 (a posteriori power 4.5-100%) and the common odds ratio was 2.7 (95% CI 2.1-3.6, p <0.001). Three subgroup analyses performed gave odds ratios as: 2.2 (EITB-based studies), 3.2 (CT-based studies), 1.9 (neurologist-confirmed epilepsy; door-to-door survey and at least one matched control per case). Etiologic fraction was estimated to be 63% in the exposed group among the population. Despite differences in findings, this meta-analysis suggests that cysticercosis is a significant contributor to late-onset epilepsy in tropical regions around the world, and its impact may vary depending on transmission intensity.

Risk factors for infection with highly pathogenic influenza A virus (H5N1) in commercial chickens in Bangladesh.

PubMed

Biswas, P K; Christensen, J P; Ahmed, S S U; Barua, H; Das, A; Rahman, M H; Giasuddin, M; Hannan, A S M A; Habib, A M; Debnath, N C

2009-06-13

A matched case-control study was carried out to identify risk factors for highly pathogenic avian influenza A virus (subtype H5N1) infection in commercial chickens in Bangladesh. A total of 33 commercial farms diagnosed with H5N1 before September 9, 2007, were enrolled as cases, and 99 geographically matched unaffected farms were enrolled as control farms. Farm data were collected using a pretested questionnaire, and analysed by matched-pair analysis and multivariate conditional logistic regression. Two factors independently and positively associated with H5N1 infection remained in the final model. They were 'farm accessible to feral and wild animals' (odds ratio [OR] 5.71, 95 per cent confidence interval [CI] 1.81 to 18.0, P=0.003) and 'footbath at entry to farm/shed' (OR 4.93, 95 per cent CI 1.61 to 15.1, P=0.005). The use of a designated vehicle for sending eggs to a vendor or market appeared to be a protective factor (OR 0.14, 95 per cent CI 0.02 to 0.88, P=0.036).

Importance of relationship context in HIV transmission: results from a qualitative case-control study in Rakai, Uganda.

PubMed

Higgins, Jenny A; Mathur, Sanyukta; Eckel, Elizabeth; Kelley, Laura; Kelly, Laura; Nakyanjo, Neema; Sekamwa, Richard; Namatovu, Josephine; Ddaaki, William; Nakubulwa, Rosette; Namakula, Sylvia; Nalugoda, Fred; Santelli, John S

2014-04-01

We present results from life history interviews with 60 young adults from southern Uganda. Using a novel qualitative case-control design, we compared newly HIV-positive cases with HIV-negative controls matched on age, gender, marital status, and place of residence. Relationship context was the most salient theme differentiating cases from controls. Compared with HIV-negative respondents, recent seroconverters described relationships marked by poorer communication, greater suspicion and mistrust, and larger and more transitory sexual networks. Results highlight the importance of dyadic approaches to HIV and possibly of couple-based interventions. Using HIV-matched pairs allowed additional understanding of the factors influencing transmission. This hybrid methodological approach holds promise for future studies of sexual health.

Importance of Relationship Context in HIV Transmission: Results From a Qualitative Case-Control Study in Rakai, Uganda

PubMed Central

Mathur, Sanyukta; Eckel, Elizabeth; Kelly, Laura; Nakyanjo, Neema; Sekamwa, Richard; Namatovu, Josephine; Ddaaki, William; Nakubulwa, Rosette; Namakula, Sylvia; Nalugoda, Fred; Santelli, John S.

2014-01-01

We present results from life history interviews with 60 young adults from southern Uganda. Using a novel qualitative case-control design, we compared newly HIV-positive cases with HIV-negative controls matched on age, gender, marital status, and place of residence. Relationship context was the most salient theme differentiating cases from controls. Compared with HIV-negative respondents, recent seroconverters described relationships marked by poorer communication, greater suspicion and mistrust, and larger and more transitory sexual networks. Results highlight the importance of dyadic approaches to HIV and possibly of couple-based interventions. Using HIV-matched pairs allowed additional understanding of the factors influencing transmission. This hybrid methodological approach holds promise for future studies of sexual health. PMID:24524490

Tramadol use and the risk of hospitalization for hypoglycemia in patients with noncancer pain.

PubMed

Fournier, Jean-Pascal; Azoulay, Laurent; Yin, Hui; Montastruc, Jean-Louis; Suissa, Samy

2015-02-01

Tramadol is a weak opioid analgesic whose use has increased rapidly, and it has been associated with adverse events of hypoglycemia. To assess whether tramadol use, when compared with codeine use, is associated with an increased risk of hospitalization for hypoglycemia. A nested case-control analysis was conducted within the United Kingdom Clinical Practice Research Datalink linked to the Hospital Episodes Statistics database of all patients newly treated with tramadol or codeine for noncancer pain between 1998 and 2012. Cohort and case-crossover analyses were also conducted to assess consistency of the results. Cases of hospitalization for hypoglycemia were matched with up to 10 controls on age, sex, and duration of follow-up. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated comparing use of tramadol with codeine. A cohort analysis, with high-dimensional propensity score-adjusted hazard ratios (HRs) and 95% CIs, was performed comparing tramadol with codeine in the first 30 days after treatment initiation. Finally, a case-crossover analysis was also performed, in which exposure to tramadol in a 30-day risk period immediately before the hospitalization for hypoglycemia was compared with 11 consecutive 30-day control periods. Odds ratios and 95% CIs were estimated using conditional logistic regression analysis. The cohort included 334,034 patients, of whom 1105 were hospitalized for hypoglycemia during follow-up (incidence, 0.7 per 1000 per year) and matched to 11,019 controls. Compared with codeine, tramadol use was associated with an increased risk of hospitalization for hypoglycemia (OR, 1.52 [95% CI, 1.09-2.10]), particularly elevated in the first 30 days of use (OR, 2.61 [95% CI, 1.61-4.23]). This 30-day increased risk was confirmed in the cohort (HR, 3.60 [95% CI, 1.56-8.34]) and case-crossover analyses (OR, 3.80 [95% CI, 2.64-5.47]). The initiation of tramadol therapy is associated with an increased risk of hypoglycemia requiring hospitalization. Additional studies are needed to confirm this rare but potentially fatal adverse event.

Prenatal folic acid use associated with decreased risk of myelomeningocele: A case-control study offers further support for folic acid fortification in Bangladesh.

PubMed

Kancherla, Vijaya; Ibne Hasan, Md Omar Sharif; Hamid, Rezina; Paul, Ligi; Selhub, Jacob; Oakley, Godfrey; Quamruzzaman, Quazi; Mazumdar, Maitreyi

2017-01-01

Neural tube defects contribute to severe morbidity and mortality in children and adults; however, they are largely preventable through maternal intake of folic acid before and during early pregnancy. We examined the association between maternal prenatal folic acid supplement intake and risk of myelomeningocele (a severe and common type of neural tube defect) in the offspring. We performed secondary analysis using data from a case-control study conducted at Dhaka Community Hospital, Bangladesh between April and November of 2013. Cases and controls included children with and without myelomeningocele, respectively, and their mothers. Cases were identified from local hospitals and rural health clinics served by Dhaka Community Hospital. Controls were selected from pregnancy registries located in the same region as the cases, and matched (1:1) to cases by age and sex. Myelomeningocele in the offspring was confirmed by a pediatrician with expertise in classifying neural tube defects. Maternal prenatal folic acid supplement intake was the main exposure of interest. We estimated crude and adjusted odds ratios (OR) and 95% confidence intervals (CI) using conditional logistic regression analysis. There were 53 pairs of matched cases and controls in our study. Overall, 51% of case mothers reported using folic acid supplements during pregnancy compared to 72% of control mothers (p = 0.03). Median plasma folate concentrations at the time of study visit were 2.79 ng/mL and 2.86 ng/mL among case and control mothers, respectively (p = 0.85). Maternal prenatal folic acid use significantly decreased the odds of myelomeningocele in the offspring (unadjusted OR = 0.42, 95% CI = 0.18-0.96). The association was slightly attenuated after adjusting for maternal age at the time of pregnancy (adjusted OR = 0.43, 95% CI = 0.18-1.02). Our study confirms the protective association between maternal prenatal folic acid supplement use and myelomeningocele among children born in Bangladesh. Our findings point to an overall low folic acid supplement use and low plasma folate concentrations among women of reproductive age in Bangladesh. Mandatory fortification of staple foods with folic acid can address low folate status among women of child-bearing age, and prevent child morbidity and mortality associated with myelomeningocele in Bangladesh.

Relationship between C-Reactive Protein Level and Diabetic Retinopathy: A Systematic Review and Meta-Analysis

PubMed Central

Chen, Song; Duan, Hongtao; Kong, Jiahui; Li, Zedong

2015-01-01

Objectives To date, the relationship between C-reactive protein (CRP) level and diabetic retinopathy (DR) remains controversial. Therefore, a systematic review and meta-analysis was used to reveal the potential relationship between CRP level and DR. Methods A systematic search of PubMed, Embase.com, and Web of Science was performed to identify all comparative studies that compared the CRP level of two groups (case group and control group). We defined that diabetic patients without retinopathy and /or matched healthy persons constituted the control group, and patients with DR were the case group. Results Two cross sectional studies and twenty case control studies including a total of 3679 participants were identified. After pooling the data from all 22 studies, obvious heterogeneity existed between the studies, so a subgroup analysis and sensitivity analysis were performed. Removing the sensitivity studies, the blood CRP levels in the case group were observed to be higher than those in the control group [SMD = 0.22, 95% confidence interval (CI), 0.11–0.34], and the blood CRP levels in the proliferative diabetic retinopathy (PDR) group were also higher than those in the non-proliferative diabetic retinopathy (NPDR) group [SMD = 0.50, 95% CI, 0.30–0.70]. Conclusions The results from this current meta-analysis indicate that the CRP level might be used as a biomarker to determine the severity of DR. PMID:26636823

Risk of Radiation-Induced Malignancy With Heterotopic Ossification Prophylaxis: A Case–Control Analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sheybani, Arshin, E-mail: arshin-sheybani@uiowa.edu; TenNapel, Mindi J.; Lack, William D.

2014-07-01

Purpose: To determine the risk of radiation-induced malignancy after prophylactic treatment for heterotopic ossification (HO). Methods and Materials: A matched case–control study was conducted within a population-based cohort of 3489 patients treated either for acetabular fractures with acetabular open reduction internal fixation or who underwent total hip arthroplasty from 1990 to 2009. Record-linkage techniques identified patients who were diagnosed with a malignancy from our state health registry. Patients with a prior history of malignancy were excluded from the cohort. For each documented case of cancer, 2 controls were selected by stratified random sampling from the cohort that did not developmore » a malignancy. Matching factors were sex, age at time of hip treatment, and duration of follow-up. Results: A total of 243 patients were diagnosed with a malignancy after hip treatment. Five patients were excluded owing to inadequate follow-up time in the corresponding control cohort. A cohort of 238 cases (control, 476 patients) was included. Mean follow-up was 10 years, 12 years in the control group. In the cancer cohort, 4% of patients had radiation therapy (RT), compared with 7% in the control group. Of the 9 patients diagnosed with cancer after RT, none occurred within the field. The mean latency period was 5.9 years in the patients who received RT and 6.6 years in the patients who did not. Median (range) age at time of cancer diagnosis in patients who received RT was 62 (43-75) years, compared with 70 (32-92) years in the non-RT patients. An ad hoc analysis was subsequently performed in all 2749 patients who were not matched and found neither an increased incidence of malignancy nor a difference in distribution of type of malignancy. Conclusion: We were unable to demonstrate an increased risk of malignancy in patients who were treated with RT for HO prophylaxis compared with those who were not.« less

Possible association between different congenital abnormalities and use of different sulfonamides during pregnancy.

PubMed

Czeizel, Andrew E; Puhó, Erzsébet; Sørensen, Henrik T; Olsen, Jørn

2004-06-01

The objective of the study presented here was to check the debated human teratogenic potential of sulfonamide drugs. Five different sulfonamides such as sulfamethazine, sulfathiourea, sulfamethoxypyridazine, sulfamethoxydiazine and the combination of sulfamethazine-sulfathiourea-sulfamethoxypyridazine were differentiated. Cases with congenital abnormalities were compared with their matched controls without congenital abnormalities in the population-based large data set of the Hungarian Case-Control Surveillance of Congenital Abnormalities between 1980 and 1996. Of 38,151 newborn infants without any congenital abnormalities (control group), 163 (0.4%) had mothers who were treated with the sulfonamides studied during pregnancy, while of 22,843 cases with congenital abnormalities, 140 (0.6%) had mothers who were treated with the sulfonamides studied during pregnancy. The analysis of cases and matched controls indicated a higher rate of cardiovascular malformation (adjusted prevalence odds ratios [POR] with 95% CI: 3.5, 1.9-6.4) and clubfoot (adjusted POR with 95% CI: 2.6, 1.1-6.2) in infants born to mothers with sulfonamide treatment in the second and third months of pregnancy. The detailed analysis of different sulfonamides showed a possible association between cardiovascular malformations (adjusted POR with 95%; CI: 6.5, 2.6-15.9), particularly ventricular septal defect (17.1, 1.3-141.1) and sulfamethoxydiazine during the second and third months of pregnancy. In addition, a possible association was found between clubfoot and sulfathiourea, both during the entire pregnancy (adjusted POR with 95% CI: 2.3, 1.2-4.3) and in the second and third months of gestation (3.9, 1.1-13.8). Thus, maternal treatment of sulfamethoxydiazine may cause ventricular septal defect, while sulfathiourea may induce clubfoot; however, further studies are needed to verify or reject these associations.

Identification and selection of cases and controls in the Pneumonia Etiology Research for Child Health project.

PubMed

Deloria-Knoll, Maria; Feikin, Daniel R; Scott, J Anthony G; O'Brien, Katherine L; DeLuca, Andrea N; Driscoll, Amanda J; Levine, Orin S

2012-04-01

Methods for the identification and selection of patients (cases) with severe or very severe pneumonia and controls for the Pneumonia Etiology Research for Child Health (PERCH) project were needed. Issues considered include eligibility criteria and sampling strategies, whether to enroll hospital or community controls, whether to exclude controls with upper respiratory tract infection (URTI) or nonsevere pneumonia, and matching criteria, among others. PERCH ultimately decided to enroll community controls and an additional human immunodeficiency virus (HIV)-infected control group at high HIV-prevalence sites matched on age and enrollment date of cases; controls with symptoms of URTI or nonsevere pneumonia will not be excluded. Systematic sampling of cases (when necessary) and random sampling of controls will be implemented. For each issue, we present the options that were considered, the advantages and disadvantages of each, the rationale for the methods selected for PERCH, and remaining implications and limitations.

No effect of 2008/09 seasonal influenza vaccination on the risk of pandemic H1N1 2009 influenza infection in England.

PubMed

Pebody, Richard; Andrews, Nick; Waight, Pauline; Malkani, Rashmi; McCartney, Christine; Ellis, Joanna; Miller, Elizabeth

2011-03-21

This study reports effectiveness of trivalent influenza vaccine (TIV) against confirmed pandemic influenza infection in England using a retrospective test-negative case-control study. Cases and controls were frequency matched by age, swabbing-week and region. On univariable and multivariable analysis adjusted for underlying clinical risk factors, cases were no more or less likely than controls to be vaccinated with 2008-09 or 2007-08 season TIV. Adjusted vaccine effectiveness for the former was -6% (-43% to 22%). Vaccine effectiveness did not differ significantly by age-group or hospitalisation status. There was no evidence prior vaccination with TIV significantly altered subsequent risk of pandemic influenza H1N1 2009 infection. Copyright © 2011 Elsevier Ltd. All rights reserved.

Contacts with children and young people and adult risk of suffering herpes zoster.

PubMed

Salleras, M; Domínguez, A; Soldevila, N; Prat, A; Garrido, P; Torner, N; Borrás, E; Salleras, L

2011-10-13

We carried out a matched case-control study to analyze the possible association between exposure to the children and the risk of suffering herpes-zoster in adulthood. Cases of herpes zoster in immunocompetent healthy patients aged ≥ 25 years seen in the dermatology department of the Sagrado Corazón Hospital in 2007-2008 were matched with four controls. Data were analyzed using conditional logistic regression. 153 cases and 604 matched controls were included. Contacts with children were significantly associated with a reduction in the risk of suffering herpes zoster in adulthood (adjusted OR 0.56 [0.37-0.85]). Herpes-zoster vaccination in immunocompetent people aged ≥ 50 years could counteract the possible negative effects of mass varicella vaccination in childhood on the epidemiology of herpes zoster in adults. Copyright © 2011 Elsevier Ltd. All rights reserved.

Somatoform disorder as a predictor of interstitial cystitis/bladder pain syndrome: Evidence from a nested case-control study and a retrospective cohort study.

PubMed

Chen, I-Chun; Lee, Ming-Huei; Lin, Hsuan-Hung; Wu, Shang-Liang; Chang, Kun-Min; Lin, Hsiu-Ying

2017-05-01

Interstitial cystitis/bladder pain syndrome (IC/BPS) has several well-known comorbid psychiatric manifestations, including insomnia, anxiety, and depression. We hypothesized that somatoform disorder, which is a psychosomatic disease, can be used as a sensitive psychiatric phenotype of IC/BPS. We investigated whether somatoform disorder increases the risk of IC/BPS.A nested case-control study and a retrospective cohort study were followed up over a 12-year period (2002-2013) in the Taiwan Health Insurance Reimbursement Database. In the nested case-control study, 1612 patients with IC/BPS were matched in a 1:2 ratio to 3224 controls based on propensity scores. The odds ratio for somatoform disorder was calculated using conditional logistic regression analysis. In the retrospective cohort study, 1436 patients with somatoform disorder were matched in a 1:2 ratio to 2872 patients with nonsomatoform disorder based on propensity scores. Cox regression analysis was used to estimate the hazard ratio associated with the development of IC/BPS in patients with somatoform disorder, and the cumulative survival probability was tested using the Kaplan-Meier analysis.We found that the odds ratio for somatoform disorder was 2.46 (95% confidence interval [CI], 1.05-5.76). Although the average time until IC/BPS development in the control subjects was 11.5 ± 1.3 years, this interval was shorter in patients with somatoform disorder (6.3 ± 3.6 years). The hazard ratio for developing IC/BPS was 2.50 (95% CI 1.23-5.58); the adjusted hazard ratio was 2.26 (95% CI 1.002-5.007). The patients and controls also differed significantly in their cumulative survival probability for IC/BPS (log rank P < .05).Evidence from the nested case-control study and retrospective cohort study consistently indicated that somatoform disorder increases the risk for IC/BPS. Our study suggests that somatoform disorder can be used as a sensitive psychiatric phenotype to predict IC/BPS. Any past history of somatoform disorder should be documented while examining patients with IC/BPS.

Longitudinal plasma metanephrines preceding pheochromocytoma diagnosis: a retrospective case-control serum repository study.

PubMed

Olson, S W; Yoon, S; Baker, T; Prince, L K; Oliver, D; Abbott, K C

2016-03-01

Plasma metanephrines (PMN) are highly sensitive for diagnosis of pheochromocytoma, but the natural history of PMN before pheochromocytoma diagnosis has not been previously described. The aim of the study was to compare the progression of PMN before pheochromocytoma diagnosis to matched healthy and essential hypertension disease controls. A retrospective case-control Department of Defense Serum Repository (DoDSR) study. We performed a DoDSR study that compared three longitudinal pre-diagnostic PMN for 30 biopsy-proven pheochromocytoma cases to three longitudinal PMN for age, sex, race, and age of serum sample matched healthy and essential hypertension disease controls. Predominant metanephrine (MN) or normetanephrine (NMN) production was identified for each case and converted to a percentage of the upper limit of normal to allow analysis of all cases together. PMN were measured by Quest Diagnostics. The predominant plasma metanephrine (PPM) was >100 and 300% of the upper limit of normal a median of 6.6 and 4.1 years before diagnosis respectively. A greater percentage of pheochromocytoma patients had a PPM >100 and >300% of the upper limit of normal compared with combined healthy and essential hypertension disease controls <2, 2-8, and >8 years prior to diagnosis. For patients with a baseline PPM 90-300% of the upper limit of normal, a 25% rate of rise per year was 100% specific for pheochromocytoma. PPMs elevate years before diagnosis which suggests that delayed diagnoses are common. For mild PMN elevations, follow-up longitudinal PMN trends may provide a highly specific and economical diagnostic tool. © 2016 European Society of Endocrinology.

Advance Care Planning in an Accountable Care Organization Is Associated with Increased Advanced Directive Documentation and Decreased Costs.

PubMed

Bond, William F; Kim, Minchul; Franciskovich, Chris M; Weinberg, Jason E; Svendsen, Jessica D; Fehr, Linda S; Funk, Amy; Sawicki, Robert; Asche, Carl V

2018-04-01

Advance care planning (ACP) documents patient wishes and increases awareness of palliative care options. To study the association of outpatient ACP with advanced directive documentation, utilization, and costs of care. This was a case-control study of cases with ACP who died matched 1:1 with controls. We used 12 months of data pre-ACP/prematch and predeath. We compared rates of documentation with logit model regression and conducted a difference-in-difference analysis using generalized linear models for utilization and costs. Medicare beneficiaries attributed to a large rural-suburban-small metro multisite accountable care organization from January 2013 to April 2016, with cross reference to ACP facilitator logs to find cases. The presence of advance directive forms was verified by chart review. Cost analysis included all utilization and costs billed to Medicare. We matched 325 cases and 325 controls (51.1% female and 48.9% male, mean age 81). 320/325 (98.5%) ACP versus 243/325 (74.8%) of controls had a Healthcare Power of Attorney (odds ratio [OR] 21.6, 95% CI 8.6-54.1) and 172/325(52.9%) ACP versus 145/325 (44.6%) controls had Practitioner Orders for Life Sustaining Treatment (OR 1.40, 95% CI 1.02-1.90) post-ACP/postmatch. Adjusted results showed ACP cases had fewer inpatient admissions (-0.37 admissions, 95% CI -0.66 to -0.08), and inpatient days (-3.66 days, 95% CI -6.23 to -1.09), with no differences in hospice, hospice days, skilled nursing facility use, home health use, 30-day readmissions, or emergency department visits. Adjusted costs were $9,500 lower in the ACP group (95% CI -$16,207 to -$2,793). ACP increases documentation and was associated with a reduction in overall costs driven primarily by a reduction in inpatient utilization. Our data set was limited by small numbers of minorities and cancer patients.

Effects of computerized match-to-sample training on emergent fraction-decimal relations in individuals with fragile X syndrome.

PubMed

Hammond, Jennifer L; Hirt, Melissa; Hall, Scott S

2012-01-01

Individuals diagnosed with fragile X syndrome (FXS), the most common known form of inherited intellectual disability, are reported to exhibit considerable deficits in mathematical skills that are often attributed to brain-based abnormalities associated with the syndrome. We examined whether participants with FXS would display emergent fraction-decimal relations following brief, intensive match-to-sample training on baseline relations. The performance profiles on tests of symmetry and transitivity/equivalence of 11 participants with FXS, aged 10-23 years, following baseline match-to-sample training were compared to those of 11 age- and IQ-matched controls with idiopathic developmental disability. The results showed that both groups of participants showed significant improvements in the baseline (trained) relations, as expected. However, participants with FXS failed to show significant improvements in the (untrained) symmetry and transitivity/equivalence relations compared to those in the control group. A categorical analysis of the data indicated that five participants with FXS and eight controls showed at least "intermediate" emergence of symmetry relations, whereas one individual with FXS and three controls showed at least intermediate emergence of transitivity/equivalence relations. A correlation analysis of the data indicated that improvements in the symmetry relations were significantly associated with improvements in the transitivity/equivalence relations in the control group (r=.69, p=.018), but this was not the case in the FXS group (r=.34, p>.05). Participant IQ was significantly associated with improvements in the symmetry relations in individuals with FXS (r=.60, p=.049), but not in controls (r=.21, p>.05). Taken together, these results suggest that brief, computerized match-to-sample training may produce emergent mathematical relations for a subset of children with FXS and developmental disabilities. However, the ability of individuals with FXS to form transitivity/equivalence relations may be impaired relative to those with idiopathic developmental disabilities, which may be attributed to neurodevelopmental variables associated with the syndrome. Copyright © 2011 Elsevier Ltd. All rights reserved.

Genome-wide Association Study of Obsessive-Compulsive Disorder

PubMed Central

Stewart, S Evelyn; Yu, Dongmei; Scharf, Jeremiah M; Neale, Benjamin M; Fagerness, Jesen A; Mathews, Carol A; Arnold, Paul D; Evans, Patrick D; Gamazon, Eric R; Osiecki, Lisa; McGrath, Lauren; Haddad, Stephen; Crane, Jacquelyn; Hezel, Dianne; Illman, Cornelia; Mayerfeld, Catherine; Konkashbaev, Anuar; Liu, Chunyu; Pluzhnikov, Anna; Tikhomirov, Anna; Edlund, Christopher K; Rauch, Scott L; Moessner, Rainald; Falkai, Peter; Maier, Wolfgang; Ruhrmann, Stephan; Grabe, Hans-Jörgen; Lennertz, Leonard; Wagner, Michael; Bellodi, Laura; Cavallini, Maria Cristina; Richter, Margaret A; Cook, Edwin H; Kennedy, James L; Rosenberg, David; Stein, Dan J; Hemmings, Sian MJ; Lochner, Christine; Azzam, Amin; Chavira, Denise A; Fournier, Eduardo; Garrido, Helena; Sheppard, Brooke; Umaña, Paul; Murphy, Dennis L; Wendland, Jens R; Veenstra-VanderWeele, Jeremy; Denys, Damiaan; Blom, Rianne; Deforce, Dieter; Van Nieuwerburgh, Filip; Westenberg, Herman GM; Walitza, Susanne; Egberts, Karin; Renner, Tobias; Miguel, Euripedes Constantino; Cappi, Carolina; Hounie, Ana G; Conceição do Rosário, Maria; Sampaio, Aline S; Vallada, Homero; Nicolini, Humberto; Lanzagorta, Nuria; Camarena, Beatriz; Delorme, Richard; Leboyer, Marion; Pato, Carlos N; Pato, Michele T; Voyiaziakis, Emanuel; Heutink, Peter; Cath, Danielle C; Posthuma, Danielle; Smit, Jan H; Samuels, Jack; Bienvenu, O Joseph; Cullen, Bernadette; Fyer, Abby J; Grados, Marco A; Greenberg, Benjamin D; McCracken, James T; Riddle, Mark A; Wang, Ying; Coric, Vladimir; Leckman, James F; Bloch, Michael; Pittenger, Christopher; Eapen, Valsamma; Black, Donald W; Ophoff, Roel A; Strengman, Eric; Cusi, Daniele; Turiel, Maurizio; Frau, Francesca; Macciardi, Fabio; Gibbs, J Raphael; Cookson, Mark R; Singleton, Andrew; Hardy, John; Crenshaw, Andrew T; Parkin, Melissa A; Mirel, Daniel B; Conti, David V; Purcell, Shaun; Nestadt, Gerald; Hanna, Gregory L; Jenike, Michael A; Knowles, James A; Cox, Nancy; Pauls, David L

2014-01-01

Obsessive-compulsive disorder (OCD) is a common, debilitating neuropsychiatric illness with complex genetic etiology. The International OCD Foundation Genetics Collaborative (IOCDF-GC) is a multi-national collaboration established to discover the genetic variation predisposing to OCD. A set of individuals affected with DSM-IV OCD, a subset of their parents, and unselected controls, were genotyped with several different Illumina SNP microarrays. After extensive data cleaning, 1,465 cases, 5,557 ancestry-matched controls and 400 complete trios remained, with a common set of 469,410 autosomal and 9,657 X-chromosome SNPs. Ancestry-stratified case-control association analyses were conducted for three genetically-defined subpopulations and combined in two meta-analyses, with and without the trio-based analysis. In the case-control analysis, the lowest two p-values were located within DLGAP1 (p=2.49×10-6 and p=3.44×10-6), a member of the neuronal postsynaptic density complex. In the trio analysis, rs6131295, near BTBD3, exceeded the genome-wide significance threshold with a p-value=3.84 × 10-8. However, when trios were meta-analyzed with the combined case-control samples, the p-value for this variant was 3.62×10-5, losing genome-wide significance. Although no SNPs were identified to be associated with OCD at a genome-wide significant level in the combined trio-case-control sample, a significant enrichment of methylation-QTLs (p<0.001) and frontal lobe eQTLs (p=0.001) was observed within the top-ranked SNPs (p<0.01) from the trio-case-control analysis, suggesting these top signals may have a broad role in gene expression in the brain, and possibly in the etiology of OCD. PMID:22889921

Sources of heterogeneity in case-control studies on associations between statins, ACE-inhibitors, and proton pump inhibitors and risk of pneumonia.

PubMed

de Groot, Mark C H; Klungel, Olaf H; Leufkens, Hubert G M; van Dijk, Liset; Grobbee, Diederick E; van de Garde, Ewoudt M W

2014-10-01

The heterogeneity in case-control studies on the associations between community-acquired pneumonia (CAP) and ACE-inhibitors (ACEi), statins, and proton pump inhibitors (PPI) hampers translation to clinical practice. Our objective is to explore sources of this heterogeneity by applying a common protocol in different data settings. We conducted ten case-control studies using data from five different health care databases. Databases varied on type of patients (hospitalised vs. GP), level of case validity, and mode of exposure ascertainment (prescription or dispensing based). Identified CAP patients and controls were matched on age, gender, and calendar year. Conditional logistic regression was used to calculate odds ratios (OR) for the associations between the drugs of interest and CAP. Associations were adjusted by a common set of potential confounders. Data of 38,742 cases and 118,019 controls were studied. Comparable patterns of variation between case-control studies were observed for ACEi, statins and PPI use and pneumonia risk with adjusted ORs varying from 1.04 to 1.49, 0.82 to 1.50 and 1.16 to 2.71, respectively. Overall, higher ORs were found for hospitalised CAP patients matched to population controls versus GP CAP patients matched to population controls. Prevalence of drug exposure was higher in dispensing data versus prescription data. We show that case-control selection and methods of exposure ascertainment induce bias that cannot be adjusted for and to a considerable extent explain the heterogeneity in results obtained in case-control studies on statins, ACEi and PPIs and CAP. The common protocol approach helps to better understand sources of variation in observational studies.

Impact of organised mammography screening on breast cancer mortality in a case–control and cohort study

PubMed Central

Heinävaara, Sirpa; Sarkeala, Tytti; Anttila, Ahti

2016-01-01

Background: The usefulness of case–control studies has been questioned. Our aim was to evaluate the long-term effect of screening on breast cancer mortality within the population-based mammography programme in Finland using a case–control design, and to compare the analyses with the earlier cohort study. Methods: The cases were women invited to screening, diagnosed and died from breast cancer in 1992–2011 while being 50–84 years at death. We chose 10 controls for each case with non-restrictive eligibility criteria. Our data included 1907 cases and 18 978 matched controls. We analysed associations between the screening participation and the risk of breast cancer death using the conditional Cox proportional hazards model. The effect estimates were corrected for self-selection bias. Results: An overall effect of screening was 0.67 (95% confidence interval (CI): 0.49–0.90), and that remained unchanged over time. Analyses with matching criteria comparable to the cohort study yielded an effect (0.70, 95% CI: 0.49–1.00) in 1992–2003 similar to that of the previous cohort analysis (0.72, 95% CI: 0.56–0.88). Conclusions: Organised mammography screening decreases mortality from breast cancer by 33% among the participants. If made comparable, a case–cohort study can yield effect estimates similar to a cohort study. PMID:27010748

[The protective efficacy of BCG against leprosy in São Paulo, Brazil].

PubMed

Lombardi, C; Pedrazzani, E S; Pedrazzani, J C; Ferreira Filho, P; Zicker, F

1995-11-01

The protection against leprosy conferred by BCG vaccination was evaluated in a case-control study. Selected for the study were 97 patients under 16 years of age who had been diagnosed with leprosy (cases) and 385 healthy persons (controls), who were matched according to sex, age, place of residence, and type of contact (intra- or extradomicilliary). The cases were selected from a register of active cases as well as a series of new leprosy patients treated in 50 centers in the city of São Paulo, Brasil. To estimate the protective effect of BCG, the prevalences of BCG scars among cases and controls were compared. The presence of one or more scars was associated with a protective efficacy of 90% (95% confidence interval: 78%-96%). Stratified analysis by age group, sex, socioeconomic level, and clinical form of leprosy did not reveal any important differences in the protection conferred by the vaccine. The significance of these findings and the appropriateness of using BCG in leprosy control programs is discussed.

Risk factors for epilepsy in Bas-Uélé Province, Democratic Republic of the Congo: a case-control study.

PubMed

Colebunders, Robert; Mandro, Michel; Mokili, John L; Mucinya, Gisele; Mambandu, Germain; Pfarr, Kenneth; Reiter-Owona, Ingrid; Hoerauf, Achim; Tepage, Floribert; Levick, Bethanie; Begon, Michael; Laudisoit, Anne

2016-08-01

The reason for the high prevalence of epilepsy in onchocerciasis endemic areas remains unknown. The aim of this study was to detect risk factors associated with epilepsy in a region endemic for onchocerciasis. In June 2014, a case-control study was performed in Titule, Bas-Uélé Province in the Democratic Republic of the Congo. Individuals with unprovoked convulsive epilepsy of unknown aetiology were enrolled as cases (n=59). Healthy members of families without cases of epilepsy in the same village were recruited as controls (n=61). A multivariate binomial logistic regression analysis was performed to identify potential risk factors associated with epilepsy. To evaluate the potential protective effect of ivermectin treatment on the development of epilepsy, a nested age-matched case-control study was performed including only those who were eligible for ivermectin treatment in the year before they developed epilepsy. Suspected onchocerciasis skin lesions were more often present in cases than in controls: 12/41 (29%) vs. 1/56 (2%), respectively (odds ratio (OR) 20.26, 95% confidence interval (CI) 2.42-170; p<0.01). Ivermectin had been taken 7 months earlier in 29/59 (49%) cases and 29/61 (48%) controls. Onchocerca volvulus (OV) DNA was detected by PCR in skin snips in 26/34 cases (76%) and 10/14 controls (71%) (p=0.7), and there was presence of OV IgG4 antibodies in 35/48 (73%) cases and 15/18 (83%) controls (p=0.5). OV DNA was not detected in the cerebrospinal fluid of cases (controls not tested). Both cases and controls reported frequent bites by blackflies (Diptera, Simuliidae). Bathing daily as opposed to less often (OR 16.7, 95% CI 2.2-125.8; p<0.01), bathing between 11 a.m. and 4 p.m. (OR 12.7, 95% CI 1.6-103.7; p=0.02), and washing clothes between 11 a.m. and 4 p.m. (OR 10.9, 95% CI 1.5-77.3; p=0.02) were all independently associated with epilepsy. Blood screening by specific PCR tests for Toxoplasma and Wuchereria bancrofti was negative in all cases and controls. A Loa loa infestation was found in only one case and one control by PCR and Giemsa smear. Antibodies to Taenia solium, Toxocara, and Trypanosoma sp were not detected in any of the participants. In an age-matched case-control analysis, 16/18 (89%) cases had not taken ivermectin the year before they developed epilepsy, compared to 7/18 (39%) controls that same year (p=0.002). These data suggest that frequent activities at rivers known to be blackfly breeding sites and a historical lack of ivermectin treatment were risk factors for epilepsy in this onchocerciasis endemic area. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Psychosocial factors in childhood pedestrian injury: a matched case-control study. Kid's'n'Cars Team.

PubMed

Christoffel, K K; Donovan, M; Schofer, J; Wills, K; Lavigne, J V

1996-01-01

Psychosocial factors--such as hyperactivity and low family cohesion--contribute to the risk for child pedestrian injury (PI), even after controlling for known demographic risk factors. Urban PI victims aged 5 to 12 years were recruited from one large, urban pediatric trauma center in a large city. One hundred twenty-eight cases were matched to uninjured children on age, sex, race, location of residence, and parental education. Among matched cases: 70% were male, 41% were black, 33% were Hispanic, and 66% of the mothers had a high school education or less. RESEARCH DESIGN AND MEASUREMENTS: Case-control comparisons on 19 psychosocial variables drawn from interviews and standardized tests, using one-tailed matched-pairs t tests and conditional logistic regression analyses. Cases had higher reported physical quotient [PQ] (P = .01), self-help quotient (P = .04), and family stress (P = .02), and lower family supportiveness (P = .03). Multivariate analyses confirmed that PQ was higher in cases (10-point increase: odds ratio (OR) = 1.32 [90% confidence interval (CI) 1.01-1.76], that stress was higher in cases (1 log increase: OR 2.13, [1.26-3.61]), and that cases had lower family supportiveness (25-point decrease: OR 1.43 [1.25-1.63]). It also identified household crowding as a factor for non-black cases (OR for increase of 0.25 people per room: 2.18, [1.31-3.62]). Even when controlling for demographic risk, several family factors and one child factor place children at risk for PI. Clinicians may choose to use these as indicators for injury prevention counseling. Research on family effects may help clarify means to protect children who are demographically at risk for PI.

Analysis of Clinical Cohort Data Using Nested Case-control and Case-cohort Sampling Designs. A Powerful and Economical Tool.

PubMed

Ohneberg, K; Wolkewitz, M; Beyersmann, J; Palomar-Martinez, M; Olaechea-Astigarraga, P; Alvarez-Lerma, F; Schumacher, M

2015-01-01

Sampling from a large cohort in order to derive a subsample that would be sufficient for statistical analysis is a frequently used method for handling large data sets in epidemiological studies with limited resources for exposure measurement. For clinical studies however, when interest is in the influence of a potential risk factor, cohort studies are often the first choice with all individuals entering the analysis. Our aim is to close the gap between epidemiological and clinical studies with respect to design and power considerations. Schoenfeld's formula for the number of events required for a Cox' proportional hazards model is fundamental. Our objective is to compare the power of analyzing the full cohort and the power of a nested case-control and a case-cohort design. We compare formulas for power for sampling designs and cohort studies. In our data example we simultaneously apply a nested case-control design with a varying number of controls matched to each case, a case cohort design with varying subcohort size, a random subsample and a full cohort analysis. For each design we calculate the standard error for estimated regression coefficients and the mean number of distinct persons, for whom covariate information is required. The formula for the power of a nested case-control design and the power of a case-cohort design is directly connected to the power of a cohort study using the well known Schoenfeld formula. The loss in precision of parameter estimates is relatively small compared to the saving in resources. Nested case-control and case-cohort studies, but not random subsamples yield an attractive alternative for analyzing clinical studies in the situation of a low event rate. Power calculations can be conducted straightforwardly to quantify the loss of power compared to the savings in the num-ber of patients using a sampling design instead of analyzing the full cohort.

Clostridium difficile infection is associated with graft loss in solid organ transplant recipients.

PubMed

Cusini, A; Béguelin, C; Stampf, S; Boggian, K; Garzoni, C; Koller, M; Manuel, O; Meylan, P; Mueller, N J; Hirsch, H H; Weisser, M; Berger, C; van Delden, C

2018-01-19

Clostridium difficile infection (CDI) is a leading cause of infectious diarrhea in solid organ transplant recipients (SOT). We aimed to assess incidence, risk factors, and outcome of CDI within the Swiss Transplant Cohort Study (STCS). We performed a case-control study of SOT recipients in the STCS diagnosed with CDI between May 2008 and August 2013. We matched 2 control subjects per case by age at transplantation, sex, and transplanted organ. A multivariable analysis was performed using conditional logistic regression to identify risk factors and evaluate outcome of CDI. Two thousand one hundred fifty-eight SOT recipients, comprising 87 cases of CDI and 174 matched controls were included. The overall CDI rate per 10 000 patient days was 0.47 (95% confidence interval ([CI] 0.38-0.58), with the highest rate in lung (1.48, 95% CI 0.93-2.24). In multivariable analysis, proven infections (hazard ratio [HR] 2.82, 95% CI 1.29-6.19) and antibiotic treatments (HR 4.51, 95% CI 2.03-10.0) during the preceding 3 months were independently associated with the development of CDI. Despite mild clinical presentations, recipients acquiring CDI posttransplantation had an increased risk of graft loss (HR 2.24, 95% CI 1.15-4.37; P = .02). These findings may help to improve the management of SOT recipients. © 2018 The American Society of Transplantation and the American Society of Transplant Surgeons.

A Prospective Study Investigating Pre-diagnostic Leukocyte Telomere Length and Risk of Developing Rheumatoid Arthritis in Women

PubMed Central

Prescott, Jennifer; Karlson, Elizabeth W.; Orr, Esther H.; Zee, Robert Y.L.; De Vivo, Immaculata; Costenbader, Karen H.

2015-01-01

Objective To prospectively examine the association between leukocyte telomere length (LTL) and subsequent RA development in women. Methods Using a case-control design nested within the prospective Nurses’ Health Study (NHS), Nurses’ Health Study II (NHSII), and Women’s Health Study (WHS), each validated case of RA with a pre-diagnostic blood sample was matched to three controls by cohort, age, menopausal status, postmenopausal hormone therapy, and blood collection covariates. We measured telomere length in genomic DNA extracted from stored buffy coat samples using quantitative PCR. We used unconditional logistic regression to determine odds ratios (OR) and 95% confidence intervals (CI), and random-effects meta-analysis to combine study results. Results In total, we analyzed 296 incident RA cases and 827 matched controls. Mean age of diagnosis among women who developed RA was 60.5 in NHS/NHSII and 61.3 in WHS. Meta-analysis demonstrated that longer pre-diagnostic LTL was associated with increased RA risk when women in the longest vs. shortest LTL tertile were compared (OR=1.51, 95% CI=1.03–2.23; pheterogeneity=0.27). However, statistically significant between study heterogeneity was observed for the intermediate tertile category (pheterogeneity=0.008). We did not observe heterogeneity by menopausal status, inflammatory cytokine levels, age at diagnosis, age at blood collection, body mass index, seropositivity, or HLA-DRB1 shared epitope status. Conclusion Our results do not support a role for short LTL preceding RA development. PMID:26773113

Sudden cardiac death in adults with congenital heart disease: does QRS-complex fragmentation discriminate in structurally abnormal hearts?

PubMed

Vehmeijer, Jim T; Koyak, Zeliha; Bokma, Jouke P; Budts, Werner; Harris, Louise; Mulder, Barbara J M; de Groot, Joris R

2018-06-01

Sudden cardiac death (SCD) causes a large portion of all mortality in adult congenital heart disease (ACHD) patients. However, identification of high-risk patients remains challenging. Fragmented QRS-complexes (fQRS) are a marker for SCD in patients with acquired heart disease but data in ACHD patients are lacking. We therefore aim to evaluate the prognostic value of fQRS for SCD in ACHD patients. From a multicentre cohort of 25 790 ACHD patients, we included tachyarrhythmic SCD cases (n = 147), and controls (n = 266) matched by age, gender, congenital defect and (surgical) intervention. fQRS was defined as ≥1 discontinuous deflection in narrow QRS-complexes, and ≥2 in wide QRS-complexes (>120 ms), in two contiguous ECG leads. We calculated odds ratios (OR) using univariable and multivariable conditional logistic regression models correcting for impaired systemic ventricular function, heart failure and QRS duration >120 ms. ECGs of 147 SCD cases (65% male, median age of death 34 years) and of 266 controls were assessed. fQRS was present in 51% of cases and 34% of controls (OR 2.0, P = 0.003). In multivariable analysis, fQRS was independently associated with SCD (OR 1.9, P = 0.01). The most common diagnose of SCD cases was tetralogy of Fallot (ToF, 34 cases). In ToF, fQRS was present in 71% of cases vs. 43% of controls (OR for SCD 2.8, P = 0.03). fQRS was independently associated with SCD in ACHD patients in a cohort of SCD patients and matched controls. fQRS may therefore contribute to the decision when evaluating ACHD patients for primary prevention of SCD.

The role of HIV infection in the etiology and epidemiology of diarrheal disease among children aged 0-59 months in Manhiça district, Rural Mozambique.

PubMed

Acácio, Sozinho; Nhampossa, Tacilta; Quintó, Llorenç; Vubil, Delfino; Sacoor, Charfudin; Kotloff, Karen; Farag, Tamer; Dilruba, Nasrin; Macete, Eusebio; Levine, Myron M; Alonso, Pedro; Mandomando, Inácio; Bassat, Quique

2018-05-28

Diarrhea is an important health problem among HIV-infected patients. This study evaluates the role of HIV on the epidemiology, etiology and severity of diarrheal disease among children. The Global Enteric Multicenter Study enrolled children with moderate-to-severe (MSD) and less severe (LSD) diarrhea between December 2007 and November 2012. One to three controls for MSD cases and one per LSD case were enrolled and matched by age, sex and neighborhood. All children were tested for HIV. Clinical, anthropometric data and stools were collected. A follow-up was performed at 60 days. 214 MSD cases and 418 controls, together with 349 LSD cases and 214 controls were tested. HIV prevalence among MSD cases was 25% (4% for matched controls) and 6% among LSD cases (6% among matched controls). HIV-infected children were more likely to have MSD (OR=5.6, p< 0.0001). Mortality rates were higher among HIV-infected children compared with uninfected (34 vs. 5 per 1000 children-weeks at risk; p=0.0039). Cryptosporidium, Giardia, EAEC (aatA only) were more prevalent among HIV-infected MSD-cases than uninfected ones. HIV is an important risk factor for MSD. The high mortality rate implies that children with MSD should be screened for HIV and managed accordingly. Copyright © 2018. Published by Elsevier Ltd.

Risk factors for the transmission of diarrhoea in children: a case-control study in rural Malaysia.

PubMed

Knight, S M; Toodayan, W; Caique, W C; Kyi, W; Barnes, A; Desmarchelier, P

1992-08-01

In response to a recorded increasing incidence of diarrhoea in Tumpat District, Malaysia, a case-control study was performed to identify modifiable risk factors for the transmission of diarrhoea, in children aged 4-59 months. Ninety-eight pairs of children, matched on age and sex, were recruited prospectively from health centres. Exposure status was determined during a home visit. Interviewers were 'blinded' as to the disease status of each child. Odds ratios were measured through matched pair analysis and conditional logistic regression. Risk factors for diarrhoea identified were: reported--drinking of unboiled water, storage of cooked food before consumption and bottle feeding; and observations--animals inside the house and absence of washing water in latrines. Water quality, source of drinking water, reported hand washing behaviour, indiscriminate defecation by children, cup use and the absence of a functional latrine were not associated with diarrhoea. Nonsignificant associations were found for: accessibility of washing water source, type of water storage container and use of fly covers for food.

Quantification of beta A4 protein deposition in the medial temporal lobe: a comparison of Alzheimer's disease and senile dementia of the Lewy body type.

PubMed

Gentleman, S M; Williams, B; Royston, M C; Jagoe, R; Clinton, J; Perry, R H; Ince, P G; Allsop, D; Polak, J M; Roberts, G W

1992-08-03

The distribution of beta-amyloid protein (beta A4) was examined in the medial temporal lobes from cases of Alzheimer's disease (AD) (n = 13), senile dementia of Lewy body type (SDLT) (n = 12) and age matched controls (n = 9). Using a previously described image analysis technique the extent of beta A4 pathology was determined in ten distinct anatomical sites within the medial temporal lobe. AD and SDLT cases contained very similar amounts of beta A4 in the areas sampled and both contained significantly more beta A4 than the age matched controls, particularly in the dentate and parahippocampal gyri. The similarity of the beta A4 load in the two conditions is in contrast to reported differences in the number of neurofibrillary tangles which can be observed. It is suggested that AD and SDLT represent a spectrum of pathology which centres around the aberrant processing of the beta A4 precursor protein.

Acute myeloid leukemia risk by industry and occupation.

PubMed

Tsai, Rebecca J; Luckhaupt, Sara E; Schumacher, Pam; Cress, Rosemary D; Deapen, Dennis M; Calvert, Geoffrey M

2014-11-01

Acute myeloid leukemia (AML) is the most common type of leukemia found in adults. Identifying jobs that pose a risk for AML may be useful for identifying new risk factors. A matched case-control analysis was conducted using California Cancer Registry data from 1988 to 2007. This study included 8999 cases of AML and 24 822 controls. Industries with a statistically significant increased AML risk were construction (matched odds ratio [mOR] = 1.13); crop production (mOR = 1.41); support activities for agriculture and forestry (mOR = 2.05); and animal slaughtering and processing (mOR = 2.09). Among occupations with a statistically significant increased AML risk were miscellaneous agricultural workers (mOR = 1.76); fishers and related fishing workers (mOR = 2.02); nursing, psychiatric and home health aides (mOR = 1.65); and janitors and building cleaners (mOR = 1.54). Further investigation is needed to confirm study findings and to identify specific exposures responsible for the increased risks.

Higher sweat chloride levels in patients with asthma: a case-control study.

PubMed

Awasthi, Shally; Dixit, Pratibha; Maurya, Nutan

2015-02-01

To screen asthmatic patients by sweat chloride test to identify proportion with Cystic Fibrosis (CF); (Sweat chloride level >60 mmol/L). Also, to compare sweat chloride levels between cases of bronchial asthma and age and sex matched healthy children aged 5 mo-15 y. The present case-control study was conducted in a tertiary care hospital in India. Cases of bronchial asthma, diagnosed by GINA guideline 2008, and age matched healthy controls were included. Case to control ratio was 2:1. Sweat Chloride test was done by Pilocarpine Iontophoresis method. From April 2010 through May 2012, 216 asthmatics and 112 controls were recruited. Among asthmatics, there was no case of Cystic Fibrosis. Mean sweat chloride levels in asthmatics was 22.39 ± 8.45 mmol/L (inter-quartile range - 15-28 mmol/L) and in controls 19.55 ± 7.04 mmol/L (inter-quartile range - 15-23.5 mmol/L) (p value = 0.048). No Cystic Fibrosis case was identified among asthmatics. Mean sweat chloride levels were higher in asthmatics as compared to controls.

Second primary malignancies after treatment for malignant lymphoma

PubMed Central

Okines, A; Thomson, C S; Radstone, C R; Horsman, J M; Hancock, B W

2005-01-01

To determine the incidence and possible causes of second primary malignancies after treatment for Hodgkin's and Non-Hodgkin's lymphoma (HL and NHL). A cohort of 3764 consecutive patients diagnosed with HL or NHL between January 1970 and July 2001 was identified using the Sheffield Lymphoma Group database. A search was undertaken for all patients diagnosed with a subsequent primary malignancy. Two matched controls were identified for each case. Odds ratios were calculated to detect and quantify any risk factors in the cases compared to their matched controls. Mean follow-up for the cohort was 5.2 years. A total of 68 patients who developed second cancers at least 6 months after their primary diagnosis were identified, giving a crude incidence of 1.89% overall: 3.21% among the patients treated for HL, 1.32% in those treated for NHL. Most common were bronchial, breast, colorectal and haematological malignancies. High stage at diagnosis almost reached statistical significance in the analysis of just the NHL patients (odds ratio=3.48; P=0.068) after adjustment for other factors. Treatment modality was not statistically significant in any analysis. High stage at diagnosis of NHL may be a risk factor for developing a second primary cancer. PMID:16106249

Interior surface materials in the home and the development of bronchial obstruction in young children in Oslo, Norway.

PubMed Central

Jaakkola, J J; Oie, L; Nafstad, P; Botten, G; Samuelsen, S O; Magnus, P

1999-01-01

OBJECTIVES: This study assessed the role of polyvinyl chloride (PVC) plastics and textile materials in the home in the development of bronchial obstruction during the first 2 years of life. METHODS: The study was a matched pair case-control study based on a cohort of 3754 newborns in Oslo in 1992 and 1993 who were followed up for 2 years. The case group consisted of 251 children with bronchial obstruction; the control group was matched one-to-one for date of birth. RESULTS: In conditional logistic regression analysis, the risk of bronchial obstruction was related to the presence of PVC flooring (adjusted odds ratio [OR] = 1.89; 95% confidence interval [CI] = 1.14, 3.14) and textile wall materials (adjusted OR = 1.58; 95% CI = 0.98, 2.54). The reference category was wood or parquet flooring and painted walls and ceiling. Further analysis revealed an exposure-response relationship between the assessed amount of PVC and other plasticizer-containing surface materials and the risk of bronchial obstruction. CONCLUSIONS: This study provides new evidence of the role of PVC and textile wall materials in the development of bronchial obstruction in young children. PMID:9949747

Interior surface materials in the home and the development of bronchial obstruction in young children in Oslo, Norway.

PubMed

Jaakkola, J J; Oie, L; Nafstad, P; Botten, G; Samuelsen, S O; Magnus, P

1999-02-01

This study assessed the role of polyvinyl chloride (PVC) plastics and textile materials in the home in the development of bronchial obstruction during the first 2 years of life. The study was a matched pair case-control study based on a cohort of 3754 newborns in Oslo in 1992 and 1993 who were followed up for 2 years. The case group consisted of 251 children with bronchial obstruction; the control group was matched one-to-one for date of birth. In conditional logistic regression analysis, the risk of bronchial obstruction was related to the presence of PVC flooring (adjusted odds ratio [OR] = 1.89; 95% confidence interval [CI] = 1.14, 3.14) and textile wall materials (adjusted OR = 1.58; 95% CI = 0.98, 2.54). The reference category was wood or parquet flooring and painted walls and ceiling. Further analysis revealed an exposure-response relationship between the assessed amount of PVC and other plasticizer-containing surface materials and the risk of bronchial obstruction. This study provides new evidence of the role of PVC and textile wall materials in the development of bronchial obstruction in young children.

Laparoscopic versus open liver segmentectomy: prospective, case-matched, intention-to-treat analysis of clinical outcomes and cost effectiveness.

PubMed

Polignano, Francesco M; Quyn, Aaron J; de Figueiredo, Rodrigo S M; Henderson, Nikola A; Kulli, Christoph; Tait, Iain S

2008-12-01

Reduction in hospital stay, blood loss, postoperative pain and complications are common findings after laparoscopic liver resection, suggesting that the laparoscopic approach may be a suitable alternative to open surgery. Some concerns have been raised regarding cost effectiveness of this procedure and potential implications of its large-scale application. Our aim has been to determine cost effectiveness of laparoscopic liver surgery by a case-matched, case-control, intention-to-treat analysis of its costs and short-term clinical outcomes compared with open surgery. Laparoscopic liver segmentectomies and bisegmentectomies performed at Ninewells Hospital and Medical School between 2005 and 2007 were considered. Resections involving more than two Couinaud segments, or involving any synchronous procedure, were excluded. An operation-magnitude-matched control group was identified amongst open liver resections performed between 2004 and 2007. Hospital costs were obtained from the Scottish Health Service Costs Book (ISD Scotland) and average national costs were calculated. Cost of theatre time, disposable surgical devices, hospital stay, and high-dependency unit (HDU) and intensive care unit (ICU) usage were the main endpoints for comparison. Secondary endpoints were morbidity and mortality. Statistical analysis was performed with Student's t-test, chi(2) and Fisher exact test as most appropriate. Twenty-five laparoscopic liver resections were considered, including atypical resection, segmentectomy and bisegmentectomy, and they were compared to 25 matching open resections. The two groups were homogeneous by age, sex, coexistent morbidity, magnitude of resection, prevalence of liver cirrhosis and indications. Operative time (p < 0.03), blood loss (p < 0.0001), Pringle manoeuvre (p < 0.03), hospital stay (p < 0.003) and postoperative complications (p < 0.002) were significantly reduced in the laparoscopic group. Overall hospital cost was significantly lower in the laparoscopic group by an average of 2,571 pounds sterling (p < 0.04). Laparoscopic liver segmentectomy and bisegmentectomy are feasible, safe and cost effective compared to similar open resections. Large-scale application of laparoscopic liver surgery could translate into significant savings to hospitals and health care programmes.

Overall survival and clinical characteristics of BRCA mutation carriers with stage I/II pancreatic cancer.

PubMed

Golan, Talia; Sella, Tal; O'Reilly, Eileen M; Katz, Matthew H G; Epelbaum, Ron; Kelsen, David P; Borgida, Ayelet; Maynard, Hannah; Kindler, Hedy; Friedmen, Eitan; Javle, Milind; Gallinger, Steven

2017-03-14

BRCA1/BRCA2 germ line (GL) mutation carriers with pancreatic adenocarcinoma (PDAC) may have distinct outcomes. We recently described an apparent more favourable prognosis of surgically resected BRCA-associated PDAC patients in a single-arm, uncontrolled, retrospective study. However, the prognostic impact of GL BRCA1/2 mutations in surgically resected PDAC has not been compared with a matched control population. A larger multi-centre, case-control retrospective analysis was performed. Cases were patients with surgically resected, BRCA1/2-associated PDAC from 2004 to 2013. Controls included surgically resected PDAC cases treated during the same time period that were either BRCA non-carriers, or had no family history of breast, ovarian or pancreatic cancers. Cases and controls were matched by: age at diagnosis (within ±5-year period) and institution. Demographics, clinical history, overall survival (OS) and disease-free survival (DFS) were abstracted from patient records. Statistical comparisons were assessed using χ 2 - and Fisher's exact test, and median DFS/OS using Kaplan-Meier method and log-rank testing. Twenty-five patients with BRCA1-(n=4) or BRCA2 (N=21)-associated resectable PDAC were identified. Mean age was 55.7 years (range, 34-78 years), 48% (n=12) were females and 76% (n=19) were Jewish. Cases were compared (1 : 2) with 49 resectable PDAC controls, and were balanced for age, ethnicity and other relevant clinical and pathological features. BRCA-associated PDAC patients received neoadjuvant, or adjuvant platinum-based treatment more frequently than controls (7 out of 8 vs 6 out of 14) and (7 out of 21 vs 3 out of 44), respectively. No significant difference in median OS (37.06 vs 38.77 months, P=0.838) and in DFS (14.3 vs 12.0 months, P=0.303) could be demonstrated between cases and controls. A trend to increased DFS was observed among BRCA-positive cases treated with neoadjuvant/adjuvant platinum-containing regimens (n=10) compared with similarly treated controls (n=7) (39.1 vs 12.4 months, P=0.255). In this retrospective analysis, the prognosis of surgically resectable BRCA-associated PDAC is no different than that of sporadic PDAC from the same institution. The role of platinum-based adjuvant therapy in this setting requires prospective investigation.

An Approach to Assess Generalizability in Comparative Effectiveness Research: A Case Study of the Whole Systems Demonstrator Cluster Randomized Trial Comparing Telehealth with Usual Care for Patients with Chronic Health Conditions.

PubMed

Steventon, Adam; Grieve, Richard; Bardsley, Martin

2015-11-01

Policy makers require estimates of comparative effectiveness that apply to the population of interest, but there has been little research on quantitative approaches to assess and extend the generalizability of randomized controlled trial (RCT)-based evaluations. We illustrate an approach using observational data. Our example is the Whole Systems Demonstrator (WSD) trial, in which 3230 adults with chronic conditions were assigned to receive telehealth or usual care. First, we used novel placebo tests to assess whether outcomes were similar between the RCT control group and a matched subset of nonparticipants who received usual care. We matched on 65 baseline variables obtained from the electronic medical record. Second, we conducted sensitivity analysis to consider whether the estimates of treatment effectiveness were robust to alternative assumptions about whether "usual care" is defined by the RCT control group or nonparticipants. Thus, we provided alternative estimates of comparative effectiveness by contrasting the outcomes of the RCT telehealth group and matched nonparticipants. For some endpoints, such as the number of outpatient attendances, the placebo tests passed, and the effectiveness estimates were robust to the choice of comparison group. However, for other endpoints, such as emergency admissions, the placebo tests failed and the estimates of treatment effect differed markedly according to whether telehealth patients were compared with RCT controls or matched nonparticipants. The proposed placebo tests indicate those cases when estimates from RCTs do not generalize to routine clinical practice and motivate complementary estimates of comparative effectiveness that use observational data. Future RCTs are recommended to incorporate these placebo tests and the accompanying sensitivity analyses to enhance their relevance to policy making. © The Author(s) 2015.

The art of matching brain tissue from patients and controls for postmortem research.

PubMed

Bao, Ai-Min; Swaab, Dick F

2018-01-01

The quality of postmortem research depends strongly on a thorough clinical investigation and documentation of the patient's disorder and therapies. In addition, a systematic and professional neuropathologic investigation of both cases and controls is absolutely crucial. In the experience of the Netherlands Brain Bank (NBB), about 20% of clinical neurologic diagnoses, despite being made in first-rate clinics, have to be revised or require an extra diagnosis after a complete and thorough review by the NBB. The neuropathology examination may reveal for instance that the "controls" already have preclinical neurodegenerative alterations. In postmortem studies the patient and control groups must be matched for as many of the known confounding factors as possible. This is necessary to make the groups as similar as possible, except for the topic being investigated. Confounding factors are present before, during, and after death. They are respectively: (1) genetic background, systemic diseases, duration and gravity of illness, medicines and addictive compounds used, age, sex, gender identity, sexual orientation, circadian and seasonal fluctuations, lateralization; (2) agonal state, stress of dying; and (3) postmortem delay, freezing procedures, fixation and storage time. Consequently, a brain bank should have a large number of controls at its disposal for appropriate matching. If matching fails for some confounders, then their influence may be determined by statistical methods such as analysis of variance or regression models. Copyright © 2018 Elsevier B.V. All rights reserved.

Impact of Resident Involvement in Neurosurgery: An American College of Surgeons’ National Surgical Quality Improvement Program Database Analysis of 33,977 Patients

PubMed Central

Kumar, Prateek; Seicean, Sinziana; Neuhauser, Duncan; Selman, Warren R.; Bambakidis, Nicholas C.

2018-01-01

Objective There is conflicting and limited literature on the effect of intraoperative resident involvement on surgical outcomes. Our study assessed effects of resident involvement on outcomes in patients undergoing neurosurgery. Methods We identified 33,977 adult neurosurgical cases from 374 hospitals in the 2006–2012 National Surgical Quality Improvement Program, a prospectively collected national database with established reproducibility and validity. Outcomes were compared according to resident involvement before and after 1:1 matching on procedure and perioperative risk factors. Results Resident involvement was documented in 13,654 cases. We matched 10,170 resident-involved cases with 10,170 attending-alone. In the matched sample, resident involvement was associated with increased surgery duration (average, 34 minutes) and slight increases in odds for prolonged hospital stay (odds ratio, 1.2; 95% confidence interval [CI], 1.2–1.3) and complications (odds ratio, 1.2; 95% CI, 1.1–1.3) including infections (odds ratio, 1.4; 95% CI, 1.2–1.7). Increased risk for infections persisted after controlling for surgery duration (odds ratio, 1.3; 95% CI, 1.1–1.5). The majority of cases were spine surgeries, and resident involvement was not associated with morbidity or mortality for malignant tumor and aneurysm patients. Training level of residents was not associated with differences in outcomes. Conclusion Resident involvement was more common in sicker patients undergoing complex procedures, consistent with academic centers undertaking more complex cases. After controlling for patient and intraoperative characteristics, resident involvement in neurosurgical cases continued to be associated with longer surgical duration and slightly higher infection rates. Longer surgery duration did not account for differences in infection rates. PMID:29656619

Maternal Infection during Pregnancy and Autism Spectrum Disorders

ERIC Educational Resources Information Center

Zerbo, Ousseny; Qian, Yinge; Yoshida, Cathleen; Grether, Judith K.; Van de Water, Judy; Croen, Lisa A.

2015-01-01

We conducted a nested case-control study including 407 cases and 2,075 frequency matched controls to investigate the association between maternal infections during pregnancy and risk of autism spectrum disorders (ASD). Cases, controls, and maternal infections were ascertained from Kaiser Permanente Northern California clinical databases. No…

Does BCG vaccine prevent tuberculous meningitis?

PubMed Central

Thilothammal, N; Krishnamurthy, P V; Runyan, D K; Banu, K

1996-01-01

The reported efficacy of BCG vaccine in preventing pulmonary tuberculosis varies from 0-80%; however, its efficacy in preventing tuberculous meningitis ranges from 52%-84%. A case-control study was conducted to assess the efficacy of BCG in preventing tuberculous meningitis in children. New cases of tuberculous meningitis, confirmed bacteriologically, were registered as cases. Controls were children suffering from febrile convulsions attending the same hospital. A total of 107 cases and 321 controls, block matched for age, were registered. Vaccination status was determined from the history reported by the mother and by BCG scar reading. Data regarding socioeconomic status, crowding, and nutritional status were collected. Using multiple logistic regression analysis the odds ratio obtained for the presence of BCG scar was 0.23 (95% confidence interval (CI) 0.14 to 0.37) and the protective efficacy of BCG vaccine in preventing tuberculous meningitis in children was found to be 77% (95% CI 71 to 83%). PMID:8660078

Alternative approaches to analytical designs in occupational injury epidemiology.

PubMed

Mittleman, M A; Maldonado, G; Gerberich, S G; Smith, G S; Sorock, G S

1997-08-01

In this paper, we discuss the theoretical framework upon which observational studies of occupational injuries are based. Following a general description of how causal effects are estimated, the challenges faced by researchers working in this area are outlined, with an emphasis on case-control studies. These challenges include defining the at-risk period for workers whose tasks change over time and whose hazard period may be very brief, evaluating the underreporting of both exposures and injuries, and considering the effects of multiple injuries per individual on study design and data analysis. We review both the theoretical and practical considerations in the design and conduct of traditional case-control studies, based on the collection of individual level data, as well as other approaches, such as using information culled from administrative and descriptive databases, and case-control studies in which the plant or work site is the unit of analysis. The case-crossover design is also reviewed and its utility for reducing confounding due to differences between individuals by self-matching is highlighted. While this design has not yet been applied to the work setting, its potential for increasing our understanding of the causes of acute-onset occupational injuries seems promising. Finally, a variety of hybrid designs are discussed, including combinations of case-control, case-crossover, and cohort designs.

Case-Control Study of Writer's Cramp

ERIC Educational Resources Information Center

Roze, E.; Soumare, A.; Pironneau, I.; Sangla, S.; de Cock, V. Cochen; Teixeira, A.; Astorquiza, A.; Bonnet, C.; Bleton, J. P.; Vidailhet, M.; Elbaz, A.

2009-01-01

Task-specific focal dystonias are thought to be due to a combination of individual vulnerability and environmental factors. There are no case-control studies of risk factors for writer's cramp. We undertook a case-control study of 104 consecutive patients and matched controls to identify risk factors for the condition. We collected detailed data…

Effect of perioperative oral care on prevention of postoperative pneumonia associated with esophageal cancer surgery: A multicenter case-control study with propensity score matching analysis.

PubMed

Soutome, Sakiko; Yanamoto, Souichi; Funahara, Madoka; Hasegawa, Takumi; Komori, Takahide; Yamada, Shin-Ichi; Kurita, Hiroshi; Yamauchi, Chika; Shibuya, Yasuyuki; Kojima, Yuka; Nakahara, Hirokazu; Oho, Takahiko; Umeda, Masahiro

2017-08-01

The aim of this study was to investigate the effectiveness of oral care in prevention of postoperative pneumonia associated with esophageal cancer surgery.Postoperative pneumonia is a severe adverse event associated with esophageal cancer surgery. It is thought to be caused by aspiration of oropharyngeal fluid containing pathogens. However, the relationship between oral health status and postoperative pneumonia has not been well investigated.This study included 539 patients with esophageal cancer undergoing surgery at 1 of 7 university hospitals. While 306 patients received perioperative oral care, 233 did not. Various clinical factors as well as occurrence of postoperative pneumonia were retrospectively evaluated. Propensity-score matching was performed to minimize selection biases associated with comparison of retrospective data between the oral care and control groups. Factors related to postoperative pneumonia were analyzed by logistic regression analysis.Of the original 539 patients, 103 (19.1%) experienced postoperative pneumonia. The results of multivariate analysis of the 420 propensity score-matched patients revealed longer operation time, postoperative dysphagia, and lack of oral care intervention to be significantly correlated with postoperative pneumonia.The present findings demonstrate that perioperative oral care can reduce the risk of postoperative pneumonia in patients undergoing esophageal cancer surgery.

Pedestrian signalization and the risk of pedestrian-motor vehicle collisions in Lima, Peru

PubMed Central

Quistberg, D. Alex; Koepsell, Thomas D.; Boyle, Linda Ng; Miranda, J. Jaime; Johnston, Brian D.; Ebel, Beth E.

2014-01-01

Safe walking environments are essential for protecting pedestrians and promoting physical activity. In Peru, pedestrians comprise of over three-quarters of road fatality victims. Pedestrian signalization plays an important role managing pedestrian and vehicle traffic and may help improve pedestrian safety. We examined the relationship between pedestrian-motor vehicle collisions and the presence of visible traffic signals, pedestrian signals, and signal timing to determine whether these countermeasures improved pedestrian safety. A matched case-control design was used where the units of study were crossing locations. We randomly sampled 97 control-matched collisions (weighted N=1134) at intersections occurring from October, 2010 to January, 2011 in Lima. Each case-control pair was matched on proximity, street classification, and number of lanes. Sites were visited between February, 2011 and September, 2011. Each analysis accounted for sampling weight and matching and was adjusted for vehicle and pedestrian traffic flow, crossing width, and mean vehicle speed. Collisions were more common where a phased pedestrian signal (green or red-lit signal) was present compared to no signalization (odds ratio [OR] 8.88, 95% Confidence Interval [CI] 1.32–59.6). A longer pedestrian-specific signal duration was associated with collision risk (OR 5.31, 95% CI 1.02–9.60 per 15-second interval). Collisions occurred more commonly in the presence of any signalization visible to pedestrians or pedestrian-specific signalization, though these associations were not statistically significant. Signalization efforts were not associated with lower risk for pedestrians; rather, they were associated with an increased risk of pedestrian-vehicle collisions. PMID:24821630

Pedestrian signalization and the risk of pedestrian-motor vehicle collisions in Lima, Peru.

PubMed

Quistberg, D Alex; Koepsell, Thomas D; Boyle, Linda Ng; Miranda, J Jaime; Johnston, Brian D; Ebel, Beth E

2014-09-01

Safe walking environments are essential for protecting pedestrians and promoting physical activity. In Peru, pedestrians comprise over three-quarters of road fatality victims. Pedestrian signalization plays an important role managing pedestrian and vehicle traffic and may help improve pedestrian safety. We examined the relationship between pedestrian-motor vehicle collisions and the presence of visible traffic signals, pedestrian signals, and signal timing to determine whether these countermeasures improved pedestrian safety. A matched case-control design was used where the units of study were crossing locations. We randomly sampled 97 control-matched collisions (weighted N=1134) at intersections occurring from October, 2010 to January, 2011 in Lima. Each case-control pair was matched on proximity, street classification, and number of lanes. Sites were visited between February, 2011 and September, 2011. Each analysis accounted for sampling weight and matching and was adjusted for vehicle and pedestrian traffic flow, crossing width, and mean vehicle speed. Collisions were more common where a phased pedestrian signal (green or red-light signal) was present compared to no signalization (odds ratio [OR] 8.88, 95% Confidence Interval [CI] 1.32-59.6). A longer pedestrian-specific signal duration was associated with collision risk (OR 5.31, 95% CI 1.02-9.60 per 15-s interval). Collisions occurred more commonly in the presence of any signalization visible to pedestrians or pedestrian-specific signalization, though these associations were not statistically significant. Signalization efforts were not associated with lower risk for pedestrians; rather, they were associated with an increased risk of pedestrian-vehicle collisions. Copyright © 2014 Elsevier Ltd. All rights reserved.

Investigation of a cluster of pituitary adenomas in workers in the aluminum industry.

PubMed

Cullen, M R; Checkoway, H; Alexander, B H

1996-11-01

Four cases of pituitary adenoma among employees at a primary aluminum production factory were identified over a five year period by a community physician. The objective of this investigation was to determine whether there has been a comparable high incidence in other aluminum factories, and if particular jobs, departments, or activities in the industry are associated with higher rates of the disease. Pituitary adenoma in employees at all United States factories of the company for the years 1989-94 was assessed by a search of a health data information bank and an insurance data base covering present and past employees of the corporation. The incidence in the aluminum workers was estimated and compared with the workers in the index plant. A nested case control study was conducted to compare employment histories of identified cases with those of age and sex matched controls selected from the health information data base. 25 cases, including the index cases, were identified which had been diagnosed during the period 1989-94. The resulting rate of 10.4/100,000 person-years was much lower than that at the index plant. Case-control analysis showed no coherent pattern of location, department, or job significantly associated with risk. In particular, jobs and departments associated with exposures common to aluminum smelting-such as coal tar pitch volatiles and fluorides-were shown to be uncommon among cases compared with age and sex matched controls. Overall, despite the unprecedented cluster at a single plant, no strong evidence was found that the rate of pituitary adenoma is increased in aluminum workers generally. We found no association with any work activity or location in the industry to suggest a work related or exposure related cause for the disease.

Differential Epidemiology of Salmonella Typhi and Paratyphi A in Kathmandu, Nepal: A Matched Case Control Investigation in a Highly Endemic Enteric Fever Setting

PubMed Central

Tran Vu Thieu, Nga; Dongol, Sabina; Le Thi Phuong, Tu; Voong Vinh, Phat; Arjyal, Amit; Martin, Laura B.; Rondini, Simona; Farrar, Jeremy J.; Dolecek, Christiane; Basnyat, Buddha; Baker, Stephen

2013-01-01

Background Enteric fever, a systemic infection caused by the bacteria Salmonella Typhi and Salmonella Paratyphi A, is endemic in Kathmandu, Nepal. Previous work identified proximity to poor quality water sources as a community-level risk for infection. Here, we sought to examine individual-level risk factors related to hygiene and sanitation to improve our understanding of the epidemiology of enteric fever in this setting. Methodology and principal findings A matched case-control analysis was performed through enrollment of 103 blood culture positive enteric fever patients and 294 afebrile community-based age and gender-matched controls. A detailed questionnaire was administered to both cases and controls and the association between enteric fever infection and potential exposures were examined through conditional logistic regression. Several behavioral practices were identified as protective against infection with enteric fever, including water storage and hygienic habits. Additionally, we found that exposures related to poor water and socioeconomic status are more influential in the risk of infection with S. Typhi, whereas food consumption habits and migration play more of a role in risk of S. Paratyphi A infection. Conclusions and significance Our work suggests that S. Typhi and S. Paratyphi A follow different routes of infection in this highly endemic setting and that sustained exposure to both serovars probably leads to the development of passive immunity. In the absence of a polyvalent vaccine against S. Typhi and S. Paratyphi A, we advocate better systems for water treatment and storage, improvements in the quality of street food, and vaccination with currently available S. Typhi vaccines. PMID:23991240

Long-Term Survival and Quality of Life After Transfusion-Associated Pulmonary Edema in Critically III Medical Patients

PubMed Central

Kojicic, Marija; Reriani, Martin K.; Fernández Pérez, Evans R.; Thakur, Lokendra; Kashyap, Rahul; Van Buskirk, Camille M.; Gajic, Ognjen

2010-01-01

Background: Transfusion-related acute lung injury (TRALI) and transfusion-associated circulatory overload (TACO) commonly complicate transfusion in critically ill patients. Prior outcome studies of TACO and TRALI have focused on short-term morbidity and mortality, but the long-term survival and quality of life (QOL) of these patients remain unknown. Methods: In a nested case-control study, we compared survival and QOL between critically ill medical patients who developed pulmonary edema after transfusion (TRALI or TACO) and medical critically ill transfused controls, matched by age, gender, and admission diagnostic group. QOL in survivors was assessed with a 36-item short form health survey 1 year after initial hospitalization. Results: Hospital, 1-year, and 2-year mortality among the 74 TRALI cases and 74 matched controls were 43.2% vs 24.3% (P = .020), 63.8% vs 46.4% (P = .037) and 74.3% vs 54.3% (P = .031), whereas among the 51 TACO cases and 51 matched controls these values were 7.8% vs 11.8% (P = .727), 38.0% vs 28.0% (P = .371), and 44.9% vs 38.8% (P = .512). When adjusted for age and baseline severity of illness in a Cox proportional hazard analysis, the development of TRALI remained associated with decreased survival (hazard ratio 1.86; 95% CI, 1.19-2.93; P = .006). Both TRALI (P = .006, P = .03) and TACO (P = .03, P = .049) were associated with prolonged ICU and hospital lengths of stay. Conclusions: In critically ill medical patients, development of TRALI, but not TACO, is independently associated with decreased long-term survival. PMID:19837827

Gastric cancer mortality and nitrate levels in Wisconsin drinking water.

PubMed

Rademacher, J J; Young, T B; Kanarek, M S

1992-01-01

The association between nitrate levels in public and private sources of drinking water and gastric cancer mortality in Wisconsin was investigated in a case-control study. All gastric cancer deaths of Wisconsin residents from 1982 through 1985 were compared with deaths from other causes (controls), and nitrate levels in the home drinking water of these residents were determined. Nitrate measures for public sources were obtained from historic nitrate data from municipal sources that existed in 1970. Nitrate measures for private water sources were obtained by testing the wells individually at the existing residences. Controls were matched individually to gastric cancer cases with respect to sex, year of birth, year of death, Wisconsin birth, and Wisconsin residency at the time of death. Matched-pair analyses were performed on the paired data, and the following levels of nitrate-nitrogen exposure were used as indicators of exposure: 0.5, 2.5, 5.0, and 10.0 mg/l. Matched-pair analysis was also performed for which private water supply constituted exposure. Odds ratios and 95% confidence intervals were, respectively, 0.92 (0.75, 1.12); 0.97 (0.74, 1.35); 0.86 (0.69, 1.08); 1.50 (0.12, 18.25); and 1.09 (0.82, 1.47) for exposure to private well-water sources. These results did not indicate an increased risk of gastric cancer at any level.

Association between biomass fuel and pulmonary tuberculosis: a nested case-control study.

PubMed

Kolappan, C; Subramani, R

2009-08-01

To quantify the association between biomass fuel usage and sputum-positive pulmonary tuberculosis. A tuberculosis prevalence survey was conducted in a random sample of 50 rural units (villages) and three urban units in the Tiruvallur district of Tamilnadu, India during the period 2001-2003. Additional data regarding exposure to tobacco smoking, alcohol consumption, biomass fuel usage and Standard of Living Index (SLI) were also collected from the study participants. A nested case-control study was carried out in this population. Cases are defined as bacteriological-positive cases diagnosed by either sputum smear or culture examination. For each case, five age- (within +/-5 years of age) and sex-matched controls were selected randomly from the non-cases residing in the same village/unit. Thus, 255 cases and 1275 controls were included in this study. The unadjusted OR measured from univariate analysis for biomass fuel is 2.9 (95% CI 1.8 to 4.7). The adjusted OR measured from multivariate analysis using Cox regression is 1.7 (95% CI 1.0 to 2.9). Thirty-six percent of cases are attributable to biomass fuel usage. The findings from this case-control study add to the evidence for an independent association between biomass smoke and pulmonary tuberculosis. Improvement in standards of living brought about by economic development will lead to more people using cleaner fuels for cooking than biomass fuel which in turn will lead to a reduction in the occurrence of pulmonary tuberculosis in the community.

Health related quality of life among myocardial infarction survivors in the United States: a propensity score matched analysis.

PubMed

Mollon, Lea; Bhattacharjee, Sandipan

2017-12-04

Little is known regarding the health-related quality of life among myocardial infarction (MI) survivors in the United States. The purpose of this population-based study was to identify differences in health-related quality of life domains between MI survivors and propensity score matched controls. This retrospective, cross-sectional matched case-control study examined differences in health-related quality of life (HRQoL) among MI survivors of myocardial infarction compared to propensity score matched controls using data from the 2015 Behavioral Risk Factor Surveillance System (BRFSS) survey. Propensity scores were generated via logistic regression for MI survivors and controls based on gender, race/ethnicity, age, body mass index (BMI), smoking status, and comorbidities. Chi-square tests were used to compare differences between MI survivors to controls for demographic variables. A multivariate analysis of HRQoL domains estimated odds ratios. Life satisfaction, sleep quality, and activity limitations were estimated using binary logistic regression. Social support, perceived general health, perceived physical health, and perceived mental health were estimated using multinomial logistic regression. Significance was set at p < 0.05. The final sample consisted of 16,729 MI survivors matched to 50,187 controls (n = 66,916). Survivors were approximately 2.7 times more likely to report fair/poor general health compared to control (AOR = 2.72, 95% CI: 2.43-3.05) and 1.5 times more likely to report limitations to daily activities (AOR = 1.46, 95% CI: 1.34-1.59). Survivors were more likely to report poor physical health >15 days in the month (AOR = 1.63, 95% CI: 1.46-1.83) and poor mental health >15 days in the month (AOR = 1.25, 95% CI: 1.07-1.46) compared to matched controls. There was no difference in survivors compared to controls in level of emotional support (rarely/never: AOR = 0.75, 95% CI: 0.48-1.18; sometimes: AOR = 0.73, 95% CI: 0.41-1.28), hours of recommended sleep (AOR = 1.14, 95% CI: 0.94-1.38), or life satisfaction (AOR = 1.62, 95% CI: 0.99-2.63). MI survivors experienced lower HRQoL on domains of general health, physical health, daily activity, and mental health compared to the general population.

Environmental arsenic exposure and risk of diabetes type 2 in Ron Phibun subdistrict, Nakhon Si Thammarat Province, Thailand: unmatched and matched case–control studies

PubMed Central

Sripaoraya, Kwanyuen; Siriwong, Wattasit; Pavittranon, Sumol; Chapman, Robert S

2017-01-01

Background There are inconsistent findings on associations between low-to-moderate level of arsenic in water and diabetes risk from previous epidemiological reports. In Ron Phibun subdistrict, Nakhon Si Thammarat Province, Thailand, a low level of arsenic exposure among population was observed and increased diabetes mellitus (DM) rate was identified. Objectives We aimed to investigate the association between determinants (including low-level water arsenic exposure) of DM type 2 risk among residents of three villages of Ron Phibun subdistrict, Nakhon Si Thammarat Province. Materials and methods Secondary data from two previous community based-studies, conducted in 2000 and 2008, were utilized. Data on independent variables relating to arsenic exposure and sociodemographic characteristics were taken from questionnaires and worksheets for health-risk screening. Water samples collected during household visit were sent for analysis of arsenic level at certified laboratories. Diabetes cases (N=185) were those who had been diagnosed with DM type 2. Two groups of controls, one unmatched to cases (n=200) and one pair matched on age and gender (n=200), were selected for analysis as unmatched and matched case–control studies, respectively. A multiple imputation technique was used to impute missing values of independent variables. Multivariable logistic regression models, with independent variables for arsenic exposure and sociodemographic characteristics, were constructed. The unmatched and matched data sets were analyzed using unconditional and conditional logistic analyses, respectively. Results Older age, body mass index (BMI), having a history of illness in siblings and parents, and drinking were associated with increased DM type 2 risk. We found no convincing association between DM type 2 risk and water arsenic concentration in either study. Conclusion We did not observe meaningful association between diabetes risk and the low-to-moderate arsenic levels observed in this study. Further research is needed to confirm this finding in the study area and elsewhere in Thailand. PMID:28442938

Results of routine restaurant inspections can predict outbreaks of foodborne illness: the Seattle-King County experience.

PubMed Central

Irwin, K; Ballard, J; Grendon, J; Kobayashi, J

1989-01-01

To analyze the association between the results of routine inspections and foodborne outbreaks in restaurants, we conducted a matched case-control study using available data from Seattle-King County, Washington. Case restaurants were facilities with a reported foodborne outbreak between January 1, 1986 and March 31, 1987 (N = 28). Two control restaurants with no reported outbreaks during this period were matched to each case restaurant on county health district and date of routine inspection (N = 56). Data from the routine inspection that preceded the outbreak (for case restaurants) or the date-matched routine inspection (for control restaurants) were abstracted from computerized inspection records. Case restaurants had a significantly lower mean inspection score (83.8 on a 0 to 100 point scale) than control restaurants (90.9). Restaurants with poor inspection scores and violations of proper temperature controls of potentially hazardous foods were, respectively, five and ten times more likely to have outbreaks than restaurants with better results. Although this study demonstrates that Seattle-King County's routine inspection form can successfully identify restaurants at increased risk of foodborne outbreaks, it also illustrates that more emphasis on regulation and education is needed to prevent outbreaks in restaurants with poor inspection results. PMID:2705592

Predictors and outcomes of superior mesenteric artery syndrome in patients with constipation: a prospective, nested case-control study.

PubMed

Xu, Lin; Yu, Wen-Kui; Lin, Zhi-Liang; Jiang, Jun; Feng, Xiao-Bo; Li, Ning

2014-10-01

Superior mesenteric artery (SMA) syndrome may occur in patients with constipation, whereas the association between these two distinct diseases has not been confirmed yet. We investigated the incidence, risk factors and treatment strategy associated with SMA syndrome in constipated patients. We conducted a prospective nested case-control study from a 9-year hospitalization cohort (n=973). Cases were matched to controls 1:4 on factors of age and gender. Cases developed SMA syndrome in long term follow-up (n=26) and controls did not (n=104). Independent risk factors were identified by using univariate analysis and conditional logistic regression analysis. Enteral nutritional support was applied in all cases and its curative effect was evaluated by retrospective analysis. The incidence of SMA syndrome was 2.67%. The risk factors under scrutiny were body mass index (BMI)≤18 (odds ratio (OR) 2.89, 95% CI 1.14 to 9.31) and abnormal colon transit time (OR 3.57, 95% CI 1.36 to 9.35). Twenty-two patients recovered after treatment of nutritional support, and the success rate of conservative treatment was 84.6%. BMI≤18 and prolonged colon transit time both were risk factors associated with SMA syndrome in constipated patients. Enteral nutritional support should be adopted as the first-line treatment for this condition.

Brick mortar exposure and chronic lymphocytic leukemia.

PubMed

Markovic-Denic, L; Jankovic, S; Marinkovic, J; Radovanovic, Z

1995-01-01

A case-control study of 130 patients with chronic lymphocytic leukemia (CLL) and 130 controls matched with respect to sex, age (2 years), type of residence (urban-rural) and area of residence (according to the national per capita income) was carried out. Conditional logistic regression analysis showed that, apart of four risk factors already described in the literature (work in a hazardous industry, hair dye use, family history of leukemia and exposure to electromagnetic radiation), brick mortar exposure was also significantly related to CLL.

Combining epidemiology and biomechanics in sports injury prevention research: a new approach for selecting suitable controls.

PubMed

Finch, Caroline F; Ullah, Shahid; McIntosh, Andrew S

2011-01-01

Several important methodological issues need to be considered when designing sports injury case-control studies. Major design goals for case-control studies include the accounting for prior injury risk exposure, and optimal definitions of both cases and suitable controls are needed to ensure this. This article reviews methodological aspects of published sports injury case-control studies, particularly with regard to the selection of controls. It argues for a new approach towards selecting controls for case-control studies that draws on an interface between epidemiological and biomechanical concepts. A review was conducted to identify sport injury case-control studies published in the peer-review literature during 1985-2008. Overall, 32 articles were identified, of which the majority related to upper or lower extremity injuries. Matching considerations were used for control selection in 16 studies. Specific mention of application of biomechanical principles in the selection of appropriate controls was absent from all studies, including those purporting to evaluate the benefits of personal protective equipment to protect against impact injury. This is a problem because it could lead to biased conclusions, as cases and controls are not fully comparable in terms of similar biomechanical impact profiles relating to the injury incident, such as site of the impact on the body. The strength of the conclusions drawn from case-control studies, and the extent to which results can be generalized, is directly influenced by the definition and recruitment of cases and appropriate controls. Future studies should consider the interface between epidemiological and biomechanical concepts when choosing appropriate controls to ensure that proper adjustment of prior exposure to injury risk is made. To provide necessary guidance for the optimal selection of controls in case-control studies of interventions to prevent sports-related impact injury, this review outlines a new case-control selection strategy that reflects the importance of biomechanical considerations, which ensures that controls are selected based on the presence of the same global injury mechanism as the cases. To summarize, the general biomechanical principles that should apply to the selection of controls in future case-control studies are as follows: (i) each control must have been exposed to the same global injury mechanism as the case, (e.g. head impact, fall onto outstretched arm); and (ii) intrinsic (individual) factors (e.g. age, sex, skill level) that might modify the person's response to the relevant biomechanical loads are adjusted when either selecting the controls or are in the analysis phase. The same considerations for control selection apply to other study designs such as matched cohort studies or case-crossover studies.

Chronic osteomyelitis correlates with increased risk of acute pancreatitis in a case-control study in Taiwan.

PubMed

Lai, Shih-Wei; Lai, Hsueh-Chou; Lin, Cheng-Li; Liao, Kuan-Fu; Tseng, Chun-Hung

2015-07-01

The objective of this study was to examine the relationship between chronic osteomyelitis and acute pancreatitis in Taiwan. This was a population-based case-control study utilizing the database of the Taiwan National Health Insurance Program. We identified 7678 cases aged 20-84 with newly diagnosed acute pancreatitis during the period of 1998 to 2011. From the same database, 30,712 subjects without diagnosis of acute pancreatitis were selected as controls. The cases and controls were matched with sex, age and index year of diagnosing acute pancreatitis. The odds ratio with 95% confidence interval of acute pancreatitis associated with chronic osteomyelitis was examined by the multivariable unconditional logistic regression analysis. After adjustment for multiple confounders, the multivariable analysis showed that the adjusted odds ratio of acute pancreatitis was 1.93 for subjects with chronic osteomyelitis (95% confidence interval 1.01, 3.69), when compared with subjects without chronic osteomyelitis. Chronic osteomyelitis correlates with increased risk of acute pancreatitis. Patients with chronic osteomyelitis should be carefully monitored about the risk of acute pancreatitis. Copyright © 2015 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.

Job and industry classifications associated with sarcoidosis in A Case-Control Etiologic Study of Sarcoidosis (ACCESS).

PubMed

Barnard, Juliana; Rose, Cecile; Newman, Lee; Canner, Martha; Martyny, John; McCammon, Chuck; Bresnitz, Eddy; Rossman, Milt; Thompson, Bruce; Rybicki, Benjamin; Weinberger, Steven E; Moller, David R; McLennan, Geoffrey; Hunninghake, Gary; DePalo, Louis; Baughman, Robert P; Iannuzzi, Michael C; Judson, Marc A; Knatterud, Genell L; Teirstein, Alvin S; Yeager, Henry; Johns, Carol J; Rabin, David L; Cherniack, Reuben

2005-03-01

To determine whether specific occupations and industries may be associated with sarcoidosis. A Case Control Etiologic Study of Sarcoidosis (ACCESS) obtained occupational and environmental histories on 706 newly diagnosed sarcoidosis cases and matched controls. We used Standard Industrial Classification (SIC) and Standard Occupational Classification (SOC) to assess occupational contributions to sarcoidosis risk. Univariable analysis identified elevated risk of sarcoidosis for workers with industrial organic dust exposures, especially in Caucasian workers. Workers for suppliers of building materials, hardware, and gardening materials were at an increased risk of sarcoidosis as were educators. Work providing childcare was negatively associated with sarcoidosis risk. Jobs with metal dust or metal fume exposures were negatively associated with sarcoidosis risk, especially in Caucasian workers. In this study, we found that exposures in particular occupational settings may contribute to sarcoidosis risk.

Hypovitaminosis D increases TB co-infection risk on HIV patients

NASA Astrophysics Data System (ADS)

Gayatri, Y. A. A. A.; Sukmawati, D. D.; Utama, S. M.; Somia, I. K. A.; Merati, T. P.

2018-03-01

Tuberculosis is causes of mortality and morbidity in patients with HIV. Hypovitaminosis D, a defective cell-mediated immune response to Mycobacterium tuberculosis infection has been extensively described in HIV patients, but studies assessing the role of vitamin D in TB-HIV co-infection are lacking. We, therefore, conducted a 1:1 pair- matched case-control study to verify hypovitaminosis D possible risk factor of TB- HIV co- infection. Consecutive HIV patients starting ARV and sex, age and CD4 cell count matched were by recruiting. Tuberculosis has confirmed by thepresence of acid-fast bacilli in sputum or mycobacterium detected in specimens culture/Gene Xpert/PCR. Vitamin D levels were by measuring direct chemiluminescent immunoassay on a LIAISON®25OH analyzer. The study comprised 25 cases and 25 controls, median (interquartile range) 25(OH)D3 serum concentration were 19.80 (12.15-27.45) ng/mL in cases and 33.30 (27.2-39.4) ng/mL in controls (P<0.001). After adjustment for potential confounders included anemia, smoking,and low BMI, with multivariate logistic regression analysis, hypovitaminosis Dindependently associated with the development of active tuberculosis in HIV patients.(OR 26.154 (90% CI: 4.371-156.541); p <0.001). The finding indicates that hypovitaminosis D was a risk factor of TB-HIV co-infection.

Effect of playing tactics on goal scoring in Norwegian professional soccer.

PubMed

Tenga, Albin; Holme, Ingar; Ronglan, Lars Tore; Bahr, Roald

2010-02-01

Methods that include an assessment of opponent interactions are thought to provide a more valid analysis of team match performance. The purpose of this study was to examine the effect of playing tactics on goal scoring by assessing opponent interactions in Norwegian elite soccer. The sample included 203 team possessions leading to goals (cases) and 1688 random team possessions (control group) from 163 of 182 (90%) matches played in the men's professional league during the 2004 season. Multidimensional qualitative data using ten ordered categorical variables were obtained to characterize each team possession. The proportion of goals scored during counterattacks (52%) was higher than during elaborate attacks (48%), while for the control group the proportion using elaborate attacks (59%) was higher than when using counterattacks (41%) (P = 0.002). Multiple logistic regression analyses showed that, for the main variable "team possession type", counterattacks were more effective than elaborate attacks when playing against an imbalanced defence (OR = 1.64; 95% confidence interval: 1.03 to 2.61; P = 0.038). Assessment of opponent interactions is critical to evaluate the effectiveness of offensive playing tactics on the probability of scoring goals, and improves the validity of team match-performance analysis in soccer.

Chromosomal DNA damage measured using the cytokinesis-block micronucleus cytome assay is significantly associated with cognitive impairment in South Australians.

PubMed

Lee, Sau Lai; Thomas, Philip; Hecker, Jane; Faunt, Jeffrey; Fenech, Michael

2015-01-01

Loss of genome integrity may be associated with increased risk for neurodegenerative disease. The aim of this study was to investigate whether mild cognitive impairment (MCI) or Alzheimer's disease (AD) individuals have increased DNA damage relative to age- and gender- matched controls using the cytokinesis-block micronucleus cytome (CBMN-Cyt) assay. DNA damage was measured as micronuclei (MN), nucleoplasmic bridges (NPB), and nuclear buds (NBUD) in binucleated cells. The assay was performed on blood samples from 80 participants consisting of (i) MCI cases (N = 20) and age- and gender- matched controls (N = 20), and (ii) AD cases (N = 20) and age- and gender- matched controls (N = 20). There was a significant increase in MCI NBUD frequency (P = 0.006) relative to controls, which was also observed in male (P = 0.03) and female (P = 0.04) subgroups. For AD cases, there were no significant differences in assay biomarkers relative to controls. There was a significant negative correlation between Mini Mental State Examination (MMSE) and (i) MN in all controls, (R = -0.3, P = 0.04), and AD cases (R = -0.4, P = 0.03), (ii) NPB in all controls, (R = -0.4, P = 0.006) and AD cases (R = -0.5, P = 0.01), and (iii) NBUD in MCI cases (R = -0.5, P = 0.007) and AD cases (R = -0.7, P = 0.0002). The results suggest that an increase in lymphocyte CBMN-Cyt DNA damage biomarkers may be associated with cognitive decline. © 2014 Wiley Periodicals, Inc.

Association of functional MMP-2 gene variant with intracranial aneurysms: case-control genetic association study and meta-analysis.

PubMed

Alg, Varinder S; Ke, Xiayi; Grieve, Joan; Bonner, Stephen; Walsh, Daniel C; Bulters, Diederik; Kitchen, Neil; Houlden, Henry; Werring, David J

2018-01-15

Abnormalities in Matrix Metalloproteinase (MMP) genes, which are important in extracellular matrix (ECM) maintenance and therefore arterial wall integrity are a plausible underlying mechanism of intracranial aneurysm (IA) formation, growth and subsequent rupture. We investigated whether the rs243865 C > T SNP (single nucleotide polymorphism) within the MMP-2 gene (which influences gene transcription) is associated with IA compared to matched controls. We conducted a case-control genetic association study, adjusted for known IA risk factors (smoking and hypertension), in a UK Caucasian population of 1409 patients with intracranial aneurysms (IA), and 1290 matched controls, to determine the association of the rs243865 C > T functional MMP-2 gene SNP with IA (overall, and classified as ruptured and unruptured). We also undertook a meta-analysis of two previous studies examining this SNP. The rs243865 T allele was associated with IA presence in univariate (OR 1.18 [95% CI 1.04-1.33], p = .01) and in multi-variable analyses adjusted for smoking and hypertension status (OR 1.16 [95% CI 1.01-1.35], p = .042). Subgroup analysis demonstrated an association of the rs243865 SNP with ruptured IA (OR 1.18 [95% CI 1.03-1.34] p = .017), but, not unruptured IA (OR 1.17 [95% CI 0.97-1.42], p = .11). Our study demonstrated an association between the functional MMP-2 rs243865 variant and IAs. Our findings suggest a genetic role for altered extracellular matrix integrity in the pathogenesis of IA development and rupture.

Use of antiepileptic drugs and risk of fractures: case-control study among patients with epilepsy.

PubMed

Souverein, P C; Webb, D J; Weil, J G; Van Staa, T P; Egberts, A C G

2006-05-09

To study the association between use of antiepileptic drugs (AEDs) and risk of fractures. The authors obtained data from the General Practice Research Database (GPRD). A case-control study was nested within a cohort of patients with active epilepsy. Cases were patients with a first fracture after cohort entry. Up to four controls were matched to each case by practice, sex, year of birth, timing of first epilepsy diagnosis, index date, and duration of GPRD history. Cumulative exposure to AEDs was assessed by summing the duration of all AED prescriptions. A distinction was made between AEDs that induce the hepatic cytochrome P-450 enzyme system and AEDs that do not. Medical conditions and drugs known to be associated with bone metabolism or falls were evaluated as potential confounders. Conditional logistic regression analysis was used to calculate odds ratios (ORs) and 95% CIs. The study population comprised 1,018 cases and 1,842 matched controls. The risk of fractures increased with cumulative duration of exposure (p for trend < 0.001), with the strongest association for greater than 12 years of use: adjusted OR 4.15 (95% CI 2.71 to 6.34). Risk estimates were higher in women than in men. There was no difference between users of AEDs that induce and AEDs that do not induce the hepatic cytochrome P-450 system. Long-term use of AEDs was associated with an increased risk of fractures, especially in women. More research on mechanisms of AED-induced bone breakdown and female vulnerability to the effects of AEDs on bone health is warranted.

Stress and psychiatric disorder in healthcare professionals and hospital staff.

PubMed

Weinberg, A; Creed, F

2000-02-12

Previous studies of stress in healthcare staff have indicated a probable high prevalence of distress. Whether this distress can be attributed to the stressful nature of the work situation is not clear. No previous study has used a detailed interview method to ascertain the link between stress in and outside of work and anxiety and depressive disorders. Doctors, nurses, and administrative and ancillary staff were screened using the general health questionnaire (GHQ). High scorers (GHQ>4) and matched individuals with low GHQ scores were interviewed by means of the clinical interview schedule to ascertain definite anxiety and depressive disorders (cases). Cases and controls, matched for age, sex, and occupational group were interviewed with the life events and difficulties schedule classification and an objective measure of work stress to find out the amount of stress at work and outside of work. Sociodemographic and stress variables were entered into a logistic-regression analysis to find out the variables associated with anxiety and depressive disorders. 64 cases and 64 controls were matched. Cases and controls did not differ on demographic variables but cases were less likely to have a confidant (odds ratio 0.09 [95% CI 0.01-0.79]) and more likely to have had a previous episode of psychiatric disorder (3.07 [1.10-8.57]). Cases and controls worked similar hours and had similar responsibility but cases had a greater number of objective stressful situations both in and out of work (severe event or substantial difficulty in and out of work-45 cases vs 18 controls 6.05 [2.81-13.00], p<0.001; severe chronic difficulty outside of work-27 vs 8, 5.12 [2.09-12.46], p<0.001). Cases had significantly more objective work problems than controls (median 6 vs 4, z=3.81, p<0.001). The logistic-regression analyses indicated that even after the effects of personal vulnerability to psychiatric disorder and ongoing social stress outside of work had been taken into account, stressful situations at work contributed to anxiety and depressive disorders. Both stress at work and outside of work contribute to the anxiety and depressive disorders experienced by healthcare staff. Our findings suggest that the best way to decrease the prevalence of these disorders is individual treatment, which may focus on personal difficulties outside of work, combined with organisational attempts to reduce work stress. The latter may involve more assistance for staff who have a conflict between their managerial role and clinical role.

Risk assessment in ginecology and obstetrics in Sicily: an approach based on Wolff's Criteria.

PubMed

Matranga, D; Marsala, M G L; Vadalà, M; Morici, M; Restivo, V; Ferrara, C; Vitale, F; Firenze, A

2013-01-01

To apply Wolff's Criteria to hospital discharge records (HDR) in order to detect adverse events worthy of further study. Gynecology and Obstetrics Units of three Sicilian hospitals were considered and HDR regarding ordinary and day hospital admissions in 2008 were collected. A matched case-control study was designed, by random selection of 10 controls at maximum for each case. Matching was performed on the variables age and speciality of admission (gynecology or obstetrics). Out of a total of 7011 HDR examined, 114 cases were identified with Wolff's Criteria. Multivariate analysis confirmed a statistically significant association with the origin of admission, diagnosis at the acceptance and length of stay: there was a decreased risk of Wolff's event in patients having urgent admission compared to elective (OR = 0.47, 95% CI = [0.28-0.78]), an increased risk in patients reporting tumor (OR = 5:41, 95 % CI [1.89-15.47]) and other causes (OR = 2.16, 95% CI [1.10-4.24]) compared to delivery diagnosis at acceptance and in patients whose length of stay was more than 6 days (OR = 23.17, 95% CI = [12.56-42.7]) compared to less or equal than 3 days Wolff's Criteria can be applied for the analysis of clinical risk in hospitals with different structural characteristics, on condition that the HDR database is complete and good quality.

Systematic review and meta-analysis estimating association of cysticercosis and neurocysticercosis with epilepsy

PubMed Central

Debacq, Gabrielle; Garcia, Héctor H.; Boumediene, Farid; Marin, Benoit; Ngoungou, Edgard B.; Preux, Pierre-Marie

2017-01-01

Background We reviewed studies that analyzed cysticercosis (CC), neurocysticercosis (NCC) and epilepsy across Latin America, Asia and Sub-Saharan Africa, to estimate the odds ratio and etiologic fraction of epilepsy due to CC in tropical regions. Methodology We conducted a systematic review of the literature on cysticercosis and epilepsy in the tropics, collecting data from case-control and cross-sectional studies. Exposure criteria for CC included one or more of the following: serum ELISA or EITB positivity, presence of subcutaneous cysts (both not verified and unverified by histology), histology consistent with calcified cysts, and brain CT scan consistent with NCC. A common odds-ratio was then estimated using meta-analysis. Principal findings 37 studies from 23 countries were included (n = 24,646 subjects, 14,934 with epilepsy and 9,712 without epilepsy). Of these, 29 were case-control (14 matched). The association between CC and epilepsy was significant in 19 scientific articles. Odds ratios ranged from 0.2 to 25.4 (a posteriori power 4.5–100%) and the common odds ratio was 2.7 (95% CI 2.1–3.6, p <0.001). Three subgroup analyses performed gave odds ratios as: 2.2 (EITB-based studies), 3.2 (CT-based studies), 1.9 (neurologist-confirmed epilepsy; door-to-door survey and at least one matched control per case). Etiologic fraction was estimated to be 63% in the exposed group among the population. Significance Despite differences in findings, this meta-analysis suggests that cysticercosis is a significant contributor to late-onset epilepsy in tropical regions around the world, and its impact may vary depending on transmission intensity. PMID:28267746

Occupational kidney disease among Chinese herbalists exposed to herbs containing aristolochic acids.

PubMed

Yang, Hsiao-Yu; Wang, Jung-Der; Lo, Tsai-Chang; Chen, Pau-Chung

2011-04-01

Many Chinese herbs contain aristolochic acids (ALAs) which are nephrotoxic and carcinogenic. The objective of this study was to identify whether exposure to herbs containing ALAs increased the risk of kidney disease among Chinese herbalists. A nested case-control study was carried out on 6538 Chinese herbalists registered between 1985 and 1998. All incident cases of chronic renal failure reported to the Database of Catastrophic Illness of the National Health Insurance Bureau between 1995 and 2000 were defined as the case group. Up to four controls without renal failure were randomly matched to each case by sex and year of birth. A structured questionnaire survey was administered between November and December 2002. The Mantel-Haenszel method and conditional logistic regression were used to estimate the risks. 40 cases and 98 matched controls were included in the final analysis. After adjusting for age, frequent analgesic use, and habitual consumption of alcohol, fermented or smoked food, we found manufacturing and selling Chinese herbal medicine (OR 3.43, 95% CI 1.16 to 10.19), processing, selling or dispensing herbal medicines containing Fangji (OR 4.17, 95% CI 1.36 to 12.81), living in the workplace (OR 3.14, 95% CI 1.11 to 8.84) and a history of taking of herbal medicines containing Fangji (frequently or occasionally) (OR 5.42, 95% CI 1.18 to 24.96) were significantly associated with renal failure. Occupational exposure to and consumption of herbs containing ALAs increases the risk of renal failure in Chinese herbalists.

Outbreak of uncommon O4 non-agglutinating Salmonella typhimurium linked to minced pork, Saxony-Anhalt, Germany, January to April 2013.

PubMed

Alt, Katja; Simon, Sandra; Helmeke, Carina; Kohlstock, Claudia; Prager, Rita; Tietze, Erhard; Rabsch, Wolfgang; Karagiannis, Ioannis; Werber, Dirk; Frank, Christina; Fruth, Angelika

2015-01-01

In January 2013, the National Reference Centre for Salmonella (NRC) detected a salmonellosis cluster in Saxony-Anhalt, Germany, caused by uncommon O4 non-agglutinating, monophasic Salmonella (S.) Typhimurium DT193. Circulating predominant monophasic S. Typhimurium DT193 clones typically display resistance phenotype ASSuT. We investigated common exposures to control the outbreak, and conducted microbiological investigations to assess the strains' phenotype. We conducted a case-control study defining cases as persons living or working in Saxony-Anhalt diagnosed with the O4 non-agglutinating strain between January and March 2013. We selected two controls contemporarily reported with norovirus infection, frequency-matched on residence and age group, per case. We interviewed regarding food consumption, especially pork and its place of purchase. We calculated odds ratios (ORs) with 95% confidence intervals (95% CI) using logistic regression. The NRC investigated human and food isolates by PCR, SDS-PAGE, MLST, PFGE, MLVA and susceptibility testing. Altogether, 68 O4 non-agglutinating human isolates were confirmed between January and April 2013. Of those, 61 were assigned to the outbreak (median age 57 years, 44% female); 83% cases ≥ 60 years were hospitalized. Eating raw minced pork from butcheries within 3 days was associated with disease (31 cases, 28 controls; OR adjusted for sex: 3.6; 95% CI: 1.0-13). Phage type DT193 and MLST ST34 were assigned, and isolates' lipopolysaccharide (LPS) matched control strains. Isolates linked to Saxony-Anhalt exhibited PFGE type 5. ASSuT- and ACSSuT phenotype proportions were 34 and 39% respectively; 54% were resistant to chloramphenicol. Three pork isolates matched the outbreak strain. Raw minced pork was the most likely infection vehicle in this first reported outbreak caused by O4 non-agglutinating, mostly chloramphenicol-resistant S. Typhimurium DT193. High hospitalization proportions demand awareness on the risk of consumption of raw pork among elderly. LPS analysis indicated O4 expression; therefore, testing with antisera from different lots is recommendable in unexpected agglutination reactions.

Issues Related to Obtaining Intelligence Quotient-Matched Controls in Autism Research

PubMed Central

Rao, Vanitha S.; Raman, Vijaya; Mysore, Ashok V.

2015-01-01

Background: Intelligence Quotient (IQ) is considered to be an index of global cognitive functioning and has traditionally been used as a fulcral measure in case-control studies in neuro-developmental disorders such as autism. Aim: The aim is to highlight the issues of “matching for IQ” with controls in autism research. Materials and Methods: Percentile scores on the Coloured Progressive Matrices of 20 children with autism in the age range of 5 to 12 years have been graphically compared with 21 age matched typically developing children. Results and Conclusions: The percentile scores of the so-called high functioning children with autism from special schools were well below that of typically developing children. There are many challenges when using IQ in case-control studies of autism. Alternative approaches need to be considered. PMID:25969598

Early Urinary Markers of Diabetic Kidney Disease: A Nested Case-Control Study From the Diabetes Control and Complications Trial (DCCT)

PubMed Central

Kern, Elizabeth O; Erhard, Penny; Sun, Wanjie; Genuth, Saul; Weiss, Miriam F

2010-01-01

Background Urinary markers were tested as predictors of macroalbuminuria or microalbuminuria in type 1 diabetes. Study Design Nested case:control of participants in the Diabetes Control and Complications Trial (DCCT) Setting & Participants Eighty-seven cases of microalbuminuria were matched to 174 controls in a 1:2 ratio, while 4 cases were matched to 4 controls in a 1:1 ratio, resulting in 91 cases and 178 controls for microalbuminuria. Fifty-five cases of macroalbuminuria were matched to 110 controls in a 1:2 ratio. Controls were free of micro/macroalbuminuria when their matching case first developed micro/macroalbuminuria. Predictors Urinary N-acetyl-β-D-glucosaminidase, pentosidine, AGE fluorescence, albumin excretion rate (AER) Outcomes Incident microalbuminuria (two consecutive annual AER > 40 but <= 300 mg/day), or macroalbuminuria (AER > 300 mg/day) Measurements Stored urine samples from DCCT entry, and 1–9 years later when macroalbuminuria or microalbuminuria occurred, were measured for the lysosomal enzyme, N-acetyl-β-D-glucosaminidase, and the advanced glycosylation end-products (AGEs) pentosidine and AGE-fluorescence. AER and adjustor variables were obtained from the DCCT. Results Sub-microalbuminuric levels of AER at baseline independently predicted microalbuminuria (adjusted OR 1.83; p<.001) and macroalbuminuria (adjusted OR 1.82; p<.001). Baseline N-acetyl-β-D-glucosaminidase independently predicted macroalbuminuria (adjusted OR 2.26; p<.001), and microalbuminuria (adjusted OR 1.86; p<.001). Baseline pentosidine predicted macroalbuminuria (adjusted OR 6.89; p=.002). Baseline AGE fluorescence predicted microalbuminuria (adjusted OR 1.68; p=.02). However, adjusted for N-acetyl-β-D-glucosaminidase, pentosidine and AGE-fluorescence lost predictive association with macroalbuminuria and microalbuminuria, respectively. Limitations Use of angiotensin converting-enzyme inhibitors was not directly ascertained, although their use was proscribed during the DCCT. Conclusions Early in type 1 diabetes, repeated measurements of AER and urinary NAG may identify individuals susceptible to future diabetic nephropathy. Combining the two markers may yield a better predictive model than either one alone. Renal tubule stress may be more severe, reflecting abnormal renal tubule processing of AGE-modified proteins, among individuals susceptible to diabetic nephropathy. PMID:20138413

Exclusive and Combined Use of Statins and Aspirin and the Risk of Pancreatic Cancer: a Case-Control Study.

PubMed

Archibugi, Livia; Piciucchi, Matteo; Stigliano, Serena; Valente, Roberto; Zerboni, Giulia; Barucca, Viola; Milella, Michele; Maisonneuve, Patrick; Delle Fave, Gianfranco; Capurso, Gabriele

2017-10-12

Data on the association between aspirin and statin use and Pancreatic Ductal AdenoCarcinoma (PDAC) risk are conflicting. These drugs are often co-prescribed, but no studies evaluated the potential combined or confounding effect of the two at the same time. We aimed to investigate the association between aspirin and statin exclusive and combined use and PDAC occurrence. Data on environmental factors, family and medical history were screened in a case-control study. PDAC cases were matched to controls for age and gender. Power calculation performed ahead. Odds ratios (OR) and 95% confidence intervals(CI) were obtained from multivariable logistic regression analysis. In 408 PDAC patients and 816 matched controls, overall statin (OR 0.61; 95%CI,0.43-0.88), but not aspirin use was associated to reduced PDAC risk. Compared to non-users, exclusive statin (OR 0.51; 95%CI,0.32-0.80) and exclusive aspirin users (OR 0.64; 95%CI,0.40-1.01) had reduced PDAC risk. Concomitant statin and aspirin use did not further reduce the risk compared with statin use alone and no interaction was evident. Statin protective association was dose-dependent, and consistent in most subgroups, being stronger in smokers, elderly, obese and non-diabetic patients. The present study suggests that statin use is associated to reduced PDAC risk, supporting a chemopreventive action of statins on PDAC.

Nitrates in municipal drinking water and non-Hodgkin lymphoma: an ecological cancer case-control study in Taiwan.

PubMed

Chang, Chih-Ching; Tsai, Shang-Shyue; Wu, Trong-Neng; Yang, Chun-Yuh

2010-01-01

The relationship between nitrate levels in drinking water and increased risk of non-Hodgkin lymphoma (NHL) development has been inconclusive. A matched cancer case-control and a nitrate ecology study was used to investigate the association between mortality attributed to NHL and nitrate exposure from Taiwan's drinking water. All deaths due to NHL in Taiwan residents from 2000 through 2006 were obtained from the Bureau of Vital Statistics of the Taiwan Provincial Department of Health. Controls were deaths from other causes and were pair-matched to the cases by gender, year of birth, and year of death. Each matched control was selected randomly from the set of possible controls for each case. Data on nitrate-nitrogen (NO(3)-N) levels of drinking water throughout Taiwan were collected from the Taiwan Water Supply Corporation (TWSC). The municipality of residence for cancer cases and controls was presumed to be the source of the subject's nitrate exposure via drinking water. The adjusted odds ratios (OR) for NHL death for those with high nitrate levels in their drinking water, as compared to the lowest tertile, were 1.02 (0.87-1.2) and 1.05 (0.89-1.24), respectively. The results of the present study show that there was no statistically significant association between nitrates in drinking water at levels in this investigation and increased risk of death attributed to NHL.

Nitrate in drinking water and risk of death from bladder cancer: an ecological case-control study in Taiwan.

PubMed

Chiu, Hui-Fen; Tsai, Shang-Shyue; Yang, Chun-Yuh

2007-06-01

The relationship between nitrate levels in drinking water and bladder cancer development is controversial. A matched cancer case-control with nitrate ecology study was used to investigate the association between bladder cancer mortality occurrence and nitrate exposure from Taiwan drinking water. All bladder cancer deaths of Taiwan residents from 1999 through 2003 were obtained from the Bureau of Vital Statistics of the Taiwan Provincial Department of Health. Controls were deaths from other causes and were pair-matched to the cases by gender, year of birth,and year of death. Each matched control was selected randomly from the set of possible controls for each cancer case. Data on nitrate-nitrogen (NO3-N) levels in drinking water throughout Taiwan were collected from Taiwan Water Supply Corporation (TWSC). The municipality of residence for cancer cases and controls was assumed to be the source of the subject's nitrate exposure via drinking water. The adjusted odds ratios for bladder cancer death for those with high nitrate levels in their drinking water were 1.76 (1.28-2.42) and 1.96 (1.41-2.72) as compared to the lowest tertile. The results of the present study show that there was a significant positive relationship between the levels of nitrate in drinking water and risk of death from bladder cancer.

Pooled analysis of case-control studies on malignant brain tumours and the use of mobile and cordless phones including living and deceased subjects.

PubMed

Hardell, Lennart; Carlberg, Michael; Hansson Mild, Kjell

2011-05-01

We studied the association between use of mobile and cordless phones and malignant brain tumours. Pooled analysis was performed of two case-control studies on patients with malignant brain tumours diagnosed during 1997-2003 and matched controls alive at the time of study inclusion and one case-control study on deceased patients and controls diagnosed during the same time period. Cases and controls or relatives to deceased subjects were interviewed using a structured questionnaire. Replies were obtained for 1,251 (85%) cases and 2,438 (84%) controls. The risk increased with latency period and cumulative use in hours for both mobile and cordless phones. Highest risk was found for the most common type of glioma, astrocytoma, yielding in the >10 year latency group for mobile phone use odds ratio (OR) = 2.7, 95% confidence interval (CI) = 1.9-3.7 and cordless phone use OR = 1.8, 95% CI = 1.2-2.9. In a separate analysis, these phone types were independent risk factors for glioma. The risk for astrocytoma was highest in the group with first use of a wireless phone before the age of 20; mobile phone use OR = 4.9, 95% CI = 2.2-11, cordless phone use OR = 3.9, 95% CI = 1.7-8.7. In conclusion, an increased risk was found for glioma and use of mobile or cordless phone. The risk increased with latency time and cumulative use in hours and was highest in subjects with first use before the age of 20.

Toxocara canis infection of children: epidemiologic and neuropsychologic findings.

PubMed Central

Marmor, M; Glickman, L; Shofer, F; Faich, L A; Rosenberg, C; Cornblatt, B; Friedman, S

1987-01-01

Sera from 4,652 children whose blood was submitted to the New York City Department of Health for lead analysis were tested for antibodies to Toxocara canis using an enzyme-linked immunosorbent assay (ELISA). Standardized to the age distribution of the study population, T. canis seropositivity (inverse titers greater than or equal to 16) was 5.7 per cent in males and 5.1 per cent in females. T. canis antibody titers and lead exposures as measured by Centers for Disease Control lead classes were positively correlated. Children who were seropositive to T. canis (cases) were compared to seronegatives (controls) matched on age (+/- 6 months), sex, time-of-screening (+/- 3 months) and CDC lead class. Logistic regression analysis of 155 case-control pairs demonstrated elevated relative risks (RRs) for geophagia (RR = 3.14; 95% CI = 1.75, 5.64) and having had a litter of puppies in the home (RR = 5.22; 95% CI = 1.63, 16.71). Compared to controls, cases had increased eosinophil counts, serum immunoglobulin E concentrations, and anti-hemagglutinin-A titers. Small deficits in cases compared to controls were found in performance on several neuropsychological tests after adjustment for potential confounders including case-control differences in race, socioeconomic status, and current blood lead concentrations. The study thus confirmed that T. canis infection is common in urban children and suggested that infection may be associated with adverse neuropsychological effects. PMID:3565646

Exchangeability in the case-crossover design

PubMed Central

Mittleman, Murray A; Mostofsky, Elizabeth

2014-01-01

In cohort and case-control studies, confounding that arises as a result of differences in the distribution of determinants of the outcome between exposure groups leading to non-exchangeability are addressed by restriction, matching or with statistical models. In case-only studies, this issue is addressed by comparing each individual with his/herself. Although case-only designs use self-matching and only include individuals who develop the outcome of interest, issues of non-exchangeability are identical to those that arise in traditional case-control and cohort studies. In this review, we describe one type of case-only design, the case-crossover design, and discuss how the concept of exchangeability can be used to understand issues of confounding, carryover effects, period effects and selection bias in case-crossover studies. PMID:24756878

Orbital fractures due to domestic violence: an epidemiologic study.

PubMed

Goldberg, Stuart H.; McRill, Connie M.; Bruno, Christopher R.; Ten Have, Tom; Lehman, Erik

2000-09-01

Domestic violence is an important cause of orbital fractures in women. Physicians who treat patients with orbital fractures may not suspect this mechanism of injury. The purpose of this study was to assess the association between domestic violence and orbital fractures. A medical center-based case-control study with matching on age and site of admission was done. Medical center databases were searched using ICD-9 codes to identify all cases of orbital fractures encountered during a three-year period. Medical records of female patients age 13 and older were reviewed along with those of age, gender and site of admission matched controls. A stratified exact test was employed to test the association between domestic violence and orbital fracture. Among 41 adult female cases with orbital fractures treated at our medical center, three (7.3%) reported domestic violence compared to zero among the matched controls (p = 0.037). We believe that domestic violence may be under-reported in both orbital fracture cases and controls. This may result in an underestimate of the orbital fracture versus domestic violence association. Domestic violence is a serious women's health and societal problem. Domestic violence may have a variety of presentations, including illnesses and injuries. Orbital fracture is an identifiable manifestation of domestic violence. Domestic violence is more likely to be detected in adult female hospital patients with orbital fracture than in matched controls with any other diagnosis. Physicians who treat patients with orbital fractures should be familiar with this mechanism of injury.

The impact of the Catholic Jubilee in 2000 on infectious diseases. A case-control study of giardiasis, Rome, Italy 2000-2001.

PubMed

Faustini, A; Marinacci, C; Fabrizi, E; Marangi, M; Recchia, O; Pica, R; Giustini, F; La Marca, A; Nacci, A; Panichi, G; Perucci, C A

2006-06-01

Mass gatherings are believed to increase the transmission of infectious diseases although surveillance systems have shown a low impact. The Catholic Jubilee was held in Rome, Italy in 2000. We conducted a case-control study to analyse the risk factors of giardiasis among residents. All diseases reported to the laboratory surveillance system from January 2000 to May 2001 were compared with hospital controls concurrently selected in the same season as cases and frequency-matched for age and birth country. Fifty-two cases (44.1%) and 72 controls were enrolled. In the multivariable analysis factors associated with giardiasis among adults were: travelling abroad (OR 24.2, P>0.01), exposure to surface water (OR 4.80, P=0.05), high educational level (OR 3.8, P=0.03). Having a maid from a high-prevalence country was independently associated (OR 2.3) although not statistically significant. This is the only exposure that changed during the Jubilee.

Clinical Risk Factors Associated With Peripartum Maternal Bacteremia.

PubMed

Easter, Sarah Rae; Molina, Rose L; Venkatesh, Kartik K; Kaimal, Anjali; Tuomala, Ruth; Riley, Laura E

2017-10-01

To evaluate risk factors associated with maternal bacteremia in febrile peripartum women. We performed a case-control study of women with fevers occurring between 7 days before and up to 42 days after delivery of viable neonates at two academic hospitals. Women with positive blood cultures were matched with the next two febrile women meeting inclusion criteria with negative blood cultures in the microbiology data without other matching parameters. We compared maternal and neonatal characteristics and outcomes between women in the case group and those in the control group with univariate analysis. We then used logistic regression to examine the association between clinical characteristics and maternal bacteremia. After excluding blood cultures positive only for contaminants, we compared 115 women in the case group with 285 in the control group. Bacteremic women were more likely to experience their initial fever during labor (40.9% compared with 22.8%, P<.01) and more likely to have fever at or above 102°F (62.6% compared with 31.6%, P<.01). These associations persisted in the adjusted analysis: multiparity (adjusted odds ratio [OR] 1.75, 95% CI 1.07-2.87), initial fever during labor (adjusted OR 2.82, 95% CI 1.70-4.70), and fever at or above 102°F (adjusted OR 3.83, 95% CI 2.37-6.19). In an analysis restricted to neonates whose mothers had initial fevers before or in the immediate 24 hours after delivery, neonates born to women in the case group had higher rates of bacteremia compared with those born to women in the control group (9.0% compared with 1.3%, P<.01). Eight of the nine bacteremic neonates born to bacteremic mothers (89%) grew the same organism as his or her mother in blood culture. Maternal bacteremia is associated with multiparity, initial fever during labor, and fever at or above 102°F; however, 37.5% of cases of bacteremia occurred in women with maximum fevers below this threshold. Obstetricians should maintain a heightened suspicion for an infectious source of fever in women with these clinical characteristics.

Risk Factors for Drug Abuse among Nepalese Samples Selected from a Town of Eastern Nepal

ERIC Educational Resources Information Center

Niraula, Surya Raj; Chhetry, Devendra Bahadur; Singh, Girish Kumar; Nagesh, S.; Shyangwa, Pramod Mohan

2009-01-01

The study focuses on the serious issue related to the adolescents' and adults' behavior and health. It aims to identify the risk factors for drug abuse from samples taken from a town of Eastern Nepal. This is a matched case-control study. The conditional logistic regression method was adopted for data analysis. The diagnosis cut off was determined…

Case control study of neuroblastoma in west-Germany after the Chernobyl accident.

PubMed

Michaelis, J; Haaf, H G; Zöllner, J; Kaatsch, P; Krummenauer, F; Berthold, F

1996-01-01

To explore possible causes of a 1988 incidence peak of infant neuroblastoma in west German regions which were contaminated with more than 6000 Bq/m2 Cs137 from the Chernobyl accident. The primary working hypothesis was that parents of the diseased children had been contaminated by an excessive intake of locally produced food, especially mushrooms or deer. Case control study with 1:2 (cases:controls) matching. Data were collected from the children's parents by questionnaires and telephone interviews. Nation-wide study (former FRG) based on the German Childhood Cancer Registry. Cases born in 1988 and reported with a neuroblastoma to the registry until March 1992. Population-based healthy controls, matched for age, sex and residence at time of diagnosis. The working hypothesis could not be confirmed by the study, because the parents of cases tended to eat less locally grown food than the parents of controls (RR = 0.63, 95% CI:0.20-1.97). Possible influence factors which previously have been described to be associated with neuroblastoma incidence could not be confirmed by the study. Parental exposure to herbicides and pesticides was associated with the occurrence of neuroblastoma (RR = 4.2, 95% CI:1.4-12.9). Neuroblastoma stage distribution in the contaminated regions was shifted towards lower stages as compared to the less contaminated regions and previous age cohorts. The study does not show additional evidence that the observed increase in neuroblastoma incidence might have been caused by exposure to fallout from the Chernobyl accident. The observed shift towards lower clinical stages may rather indicate increased diagnostic awareness. The association between neuroblastoma and parental exposure with herbicides and pesticides resulted from an extensive exploratory data analysis and needs to be confirmed in further studies.

The effect of gun control laws on hospital admissions for children in the United States.

PubMed

Tashiro, Jun; Lane, Rebecca S; Blass, Lawrence W; Perez, Eduardo A; Sola, Juan E

2016-10-01

Gun control laws vary greatly between states within the United States. We hypothesized that states with strict gun laws have lower mortality and resource utilization rates from pediatric firearms-related injury admissions. Kids' Inpatient Database (1997-2012) was searched for accidental (E922), self-inflicted (E955), assault (E965), legal intervention-related (E970), or undetermined circumstance (E985) firearm injuries. Patients were younger than 20 years and admitted for their injuries. Case incidence trends were examined for the study period. Propensity score-matched analyses were performed using 38 covariates to compare outcomes between states with strict or lenient gun control laws. Overall, 38,424 cases were identified, with an overall mortality of 7%. Firearm injuries were most commonly assault (64%), followed by accidental (25%), undetermined circumstance (7%), or self-inflicted (3%). A small minority involved military-grade weapons (0.2%). Most cases occurred in lenient gun control states (48%), followed by strict (47%) and neutral (6%).On 1:1 propensity score-matched analysis, in-hospital mortality by case was higher in lenient (7.5%) versus strict (6.5%) states, p = 0.013. Lenient states had a proportionally higher rate of accidental (31%) and self-inflicted injury (4%) versus strict states (17% and 1.6%, respectively), p < 0.001. Assault-related injuries were proportionally lower in lenient (54%) versus strict (75%) states, p < 0.001. Military-grade weapons were more common in lenient (0.4%) versus strict (0.1%) states, p = 0.001. These findings highlight the importance of legislative measures and their role in injury prevention, as firearm injuries are entirely avoidable mechanisms of injury. Lenient gun control contributes not only to worse outcomes per case, but also to a more significant and detrimental impact on public health. Epidemiologic study, level III.

Overall survival and clinical characteristics of BRCA mutation carriers with stage I/II pancreatic cancer

PubMed Central

Golan, Talia; Sella, Tal; O'Reilly, Eileen M; Katz, Matthew H G; Epelbaum, Ron; Kelsen, David P; Borgida, Ayelet; Maynard, Hannah; Kindler, Hedy; Friedmen, Eitan; Javle, Milind; Gallinger, Steven

2017-01-01

Background: BRCA1/BRCA2 germ line (GL) mutation carriers with pancreatic adenocarcinoma (PDAC) may have distinct outcomes. We recently described an apparent more favourable prognosis of surgically resected BRCA-associated PDAC patients in a single-arm, uncontrolled, retrospective study. However, the prognostic impact of GL BRCA1/2 mutations in surgically resected PDAC has not been compared with a matched control population. Methods: A larger multi-centre, case–control retrospective analysis was performed. Cases were patients with surgically resected, BRCA1/2-associated PDAC from 2004 to 2013. Controls included surgically resected PDAC cases treated during the same time period that were either BRCA non-carriers, or had no family history of breast, ovarian or pancreatic cancers. Cases and controls were matched by: age at diagnosis (within ±5-year period) and institution. Demographics, clinical history, overall survival (OS) and disease-free survival (DFS) were abstracted from patient records. Statistical comparisons were assessed using χ2- and Fisher's exact test, and median DFS/OS using Kaplan–Meier method and log-rank testing. Results: Twenty-five patients with BRCA1-(n=4) or BRCA2 (N=21)-associated resectable PDAC were identified. Mean age was 55.7 years (range, 34–78 years), 48% (n=12) were females and 76% (n=19) were Jewish. Cases were compared (1 : 2) with 49 resectable PDAC controls, and were balanced for age, ethnicity and other relevant clinical and pathological features. BRCA-associated PDAC patients received neoadjuvant, or adjuvant platinum-based treatment more frequently than controls (7 out of 8 vs 6 out of 14) and (7 out of 21 vs 3 out of 44), respectively. No significant difference in median OS (37.06 vs 38.77 months, P=0.838) and in DFS (14.3 vs 12.0 months, P=0.303) could be demonstrated between cases and controls. A trend to increased DFS was observed among BRCA-positive cases treated with neoadjuvant/adjuvant platinum-containing regimens (n=10) compared with similarly treated controls (n=7) (39.1 vs 12.4 months, P=0.255). Conclusions: In this retrospective analysis, the prognosis of surgically resectable BRCA-associated PDAC is no different than that of sporadic PDAC from the same institution. The role of platinum-based adjuvant therapy in this setting requires prospective investigation. PMID:28183138

A Two-Phase Case-Control Study of Autism Risk Among Children Born From the Late 1990s Through the Early 2000s in the United States.

PubMed

Geier, David A; Kern, Janet K; Geier, Mark R

2016-12-29

BACKGROUND This study evaluated the hypothesis that the 1999 recommendation by the American Academy of Pediatrics (AAP) and US Public Health Service (PHS) to reduce exposure to mercury (Hg) from Thimerosal in US vaccines would be associated with a reduction in the long-term risk of being diagnosed with autism. MATERIAL AND METHODS A two-phase assessment utilizing a case (n=73) -control (n=11,783) study in the Vaccine Adverse Event Reporting System (VAERS) database (for hypothesis generating) and a more rigorous, independent matched case (n=40) -control (n=40) study (hypothesis testing) was undertaken. RESULTS Analysis of the VAERS database using logistic regression revealed that the odds ratio (OR) for being an autism case in the VAERS database significantly decreased with a more recent year of vaccination in comparison to controls (OR=0.65) from 1998 to 2003. Sex-separated analyses revealed similar significant effects for males (OR=0.62) and females (OR=0.71). Analyses of the matched case-control data revealed, using the t-test statistic, that the mean date of birth among cases diagnosed with an autism spectrum disorder (ASD) (2000.5±1.2) was significantly more in the past than in controls (2001.1±1.3). Logistic regression also revealed that the OR for being diagnosed with ASD significantly decreased with a more recent date of birth in comparison to controls (OR=0.67) from 1998-2003. CONCLUSIONS This study reveals that the risk of autism during from the late1990s to early 2000s in the US significantly decreased with reductions in Hg exposure from Thimerosal-containing childhood vaccines, but future studies should examine this phenomenon in other US populations. Vaccine programs have significantly reduced the morbidity and mortality associated with infectious disease, but Thimerosal should be removed from all vaccines.

Allergies and risk of head and neck cancer: an original study plus meta-analysis.

PubMed

Hsiao, Jenn-Ren; Ou, Chun-Yen; Lo, Hung-I; Huang, Cheng-Chih; Lee, Wei-Ting; Huang, Jehn-Shyun; Chen, Ken-Chung; Wong, Tung-Yiu; Tsai, Sen-Tien; Yen, Chia-Jui; Wu, Yuan-Hua; Hsueh, Wei-Ting; Yang, Ming-Wei; Wu, Shang-Yin; Chang, Jang-Yang; Chang, Kwang-Yu; Lin, Chen-Lin; Wang, Fang-Ting; Wang, Yi-Hui; Weng, Ya-Ling; Yang, Han-Chien; Chang, Jeffrey S

2013-01-01

Although the relationship between allergy and cancer has been investigated extensively, the role of allergy in head and neck cancer (HNC) appears less consistent. It is not clear whether allergies can independently influence the risk of HNC in the presence of known strong environmental risk factors, including consumption of alcohol, betel quid, and cigarette. THE CURRENT PAPER REPORTS RESULTS FROM: 1) an original hospital-based case-control study, which included 252 incident cases of HNC and 236 controls frequency-matched to cases on sex and age; and 2) a meta-analysis combining the results of the current case-control study and 13 previously published studies (9 cohort studies with 727,569 subjects and 550 HNC outcomes and 5 case-control studies with 4,017 HNC cases and 10,928 controls). In the original case-control study, we observed a strong inverse association between allergies and HNC [odds ratio = 0.41, 95% confidence interval (CI): 0.27-0.62]. The meta-analysis also indicated a statistically significant inverse association between HNC and allergies [meta-relative risk (RR) = 0.76, 95% CI: 0.63-0.91], particularly strong for allergic rhinitis (meta-RR = 0.55, 95% CI: 0.40-0.76). In addition, the inverse association between allergies and HNC was observed only among men (meta-RR = 0.67, 95% CI: 0.54-0.84) but not among women (meta-RR = 0.98, 95% CI: 0.81-1.18). These findings suggest that immunity plays an influential role in the risk of HNC. Future studies investigating immune biomarkers, including cytokine profiles and genetic polymorphisms, are warranted to further delineate the relationship between allergies and HNC. Understanding the relationship between allergies and HNC may help devise effective strategies to reduce and treat HNC.

Dental caries experience and periodontal treatment needs of children with autistic spectrum disorder.

PubMed

Fakroon, S; Arheiam, A; Omar, S

2015-04-01

To assess dental caries experience and periodontal treatment needs among Libyan children diagnosed with autistic spectrum disorder (ASD). A cross-sectional, comparative case-control study was used, in which dental caries experience of 50 children with ASD was compared with that of 50 controls. The children with ASD were recruited from Benghazi Centre of Children with ASD, Libya. Controls were recruited from school children and matched for age, gender and socioeconomic status. DMFT, dmft for dental caries experience and CPITN for periodontal treatment needs were calculated according to WHO criteria by a calibrated examiner. Scores for DMFT as well as CPITN indices were compared using bivariate analysis. The data analysed for this study comprised observations from a group of children (cases = 50) diagnosed with ASD matched with healthy children (controls = 50). Consequently, each group consisted of 40 males and 10 females aged between 3 and 14 years (mean 7.29 ± 3.11). The ASD children showed significantly lower means for DMFT and dmft teeth as well as higher periodontal treatment needs (p > 0.05). Children with ASD were found to be more likely caries-free and have lower DMFT scores and higher unmet periodontal treatment needs than did the unaffected control children.

Epidemiologic study of residential proximity to transmission lines and childhood cancer in California: description of design, epidemiologic methods and study population

PubMed Central

Kheifets, Leeka; Crespi, Catherine M; Hooper, Chris; Oksuzyan, Sona; Cockburn, Myles; Ly, Thomas; Mezei, Gabor

2015-01-01

We conducted a large epidemiologic case-control study in California to examine the association between childhood cancer risk and distance from the home address at birth to the nearest high-voltage overhead transmission line as a replication of the study of Draper et al. in the United Kingdom. We present a detailed description of the study design, methods of case ascertainment, control selection, exposure assessment and data analysis plan. A total of 5788 childhood leukemia cases and 3308 childhood central nervous system cancer cases (included for comparison) and matched controls were available for analysis. Birth and diagnosis addresses of cases and birth addresses of controls were geocoded. Distance from the home to nearby overhead transmission lines was ascertained on the basis of the electric power companies’ geographic information system (GIS) databases, additional Google Earth aerial evaluation and site visits to selected residences. We evaluated distances to power lines up to 2000 m and included consideration of lower voltages (60–69 kV). Distance measures based on GIS and Google Earth evaluation showed close agreement (Pearson correlation >0.99). Our three-tiered approach to exposure assessment allowed us to achieve high specificity, which is crucial for studies of rare diseases with low exposure prevalence. PMID:24045429

Color and texture associations in voice-induced synesthesia

PubMed Central

Moos, Anja; Simmons, David; Simner, Julia; Smith, Rachel

2013-01-01

Voice-induced synesthesia, a form of synesthesia in which synesthetic perceptions are induced by the sounds of people's voices, appears to be relatively rare and has not been systematically studied. In this study we investigated the synesthetic color and visual texture perceptions experienced in response to different types of “voice quality” (e.g., nasal, whisper, falsetto). Experiences of three different groups—self-reported voice synesthetes, phoneticians, and controls—were compared using both qualitative and quantitative analysis in a study conducted online. Whilst, in the qualitative analysis, synesthetes used more color and texture terms to describe voices than either phoneticians or controls, only weak differences, and many similarities, between groups were found in the quantitative analysis. Notable consistent results between groups were the matching of higher speech fundamental frequencies with lighter and redder colors, the matching of “whispery” voices with smoke-like textures, and the matching of “harsh” and “creaky” voices with textures resembling dry cracked soil. These data are discussed in the light of current thinking about definitions and categorizations of synesthesia, especially in cases where individuals apparently have a range of different synesthetic inducers. PMID:24032023

A test of the occupational matching hypothesis for rehabilitation clients with severe mental illness.

PubMed

Bond, Gary R; Campbell, Kikuko; Becker, Deborah R

2013-06-01

This study compared job matching rates for clients with severe mental illness enrolled in two types of employment programs. Also examined was the occupational matching hypothesis that job matching is associated with better employment outcomes. The study involved a secondary analysis of a randomized controlled trial comparing evidence-based supported employment to a diversified placement approach. The study sample consisted of 187 participants, of whom 147 obtained a paid job during the 2-year follow-up. Jobs were coded using the Dictionary of Occupational Titles classification system. Match between initial job preferences and type of job obtained was the predictor variable. Outcomes included time to job start, job satisfaction, and job tenure on first job. Most occupational preferences were for clerical and service jobs, and most participants obtained employment in these two occupational domains. In most cases, the first job obtained matched a participant's occupational preference. The occupational matching hypothesis was not supported for any employment outcome. The occupational matching rate was similar in this study to previous studies. Most clients who obtain employment with the help of evidence-based supported employment or diversified placement services find jobs matching their occupational preference, and most often it is a rough match. Occupational matching is but one aspect of job matching; it may be time to discard actuarial classification systems such as the Dictionary of Occupational Titles as a basis for assessing job match.

[Epigenetic research of cognitive deficit in schizophrenia: some methodological considerations].

PubMed

Lezheiko, T V; Alfimova, M V

To highlights the problems of assessing cognitive deficits in schizophrenia, relevant to the epigenetic, as well as a wide range of other approaches to the search for biological bases of cognition. The literature on the weaknesses in the evaluation of cognitive functions in patients with schizophrenia are summarized and discussed. The analysis is illustrated by our experience in developing a cognitive battery and a sample to examine relationships between DNA methylation in blood cells and cognitive deficits in schizophrenia. It has been shown that to assess cognitive deficits in patients and to reduce the influence of confounders in epigenetic analysis it is necessary (1) to use a battery with the existing co-normative data in the target population, which allows to evaluate representativeness of control and patients included in the study sample, (2) to verify the theoretically driven battery structure using normative population and a cohort of patients, (3) to balance groups of cases and controls on the number, age and sex, for which an individual matching of cases and controls is best suited, (4) to conduct an additional statistical analysis controlling for education and smoking.

Relationship between ADD1 Gly460Trp gene polymorphism and essential hypertension in Madeira Island.

PubMed

Sousa, Ana Célia; Palma Dos Reis, Roberto; Pereira, Andreia; Borges, Sofia; Freitas, Ana Isabel; Guerra, Graça; Góis, Teresa; Rodrigues, Mariana; Henriques, Eva; Freitas, Sónia; Ornelas, Ilídio; Pereira, Décio; Brehm, António; Mendonça, Maria Isabel

2017-10-01

Essential hypertension (EH) is a complex disease in which physiological, environmental, and genetic factors are involved in its genesis. The genetic variant of the alpha-adducin gene (ADD1) has been described as a risk factor for EH, but with controversial results.The objective of this study was to evaluate the association of ADD1 (Gly460Trp) gene polymorphism with the EH risk in a population from Madeira Island.A case-control study with 1614 individuals of Caucasian origin was performed, including 817 individuals with EH and 797 controls. Cases and controls were matched for sex and age, by frequency-matching method. All participants collected blood for biochemical and genotypic analysis for the Gly460Trp polymorphism. We further investigated which variables were independently associated to EH, and, consequently, analyzed their interactions.In our study, we found a significant association between the ADD1 gene polymorphism and EH (odds ratio 2.484, P = .01). This association remained statistically significant after the multivariate analysis (odds ratio 2.548, P = .02).The ADD1 Gly460Trp gene polymorphism is significantly and independently associated with EH risk in our population. The knowledge of genetic polymorphisms associated with EH is of paramount importance because it leads to a better understanding of the etiology and pathophysiology of this pathology.

Relationship between ADD1 Gly460Trp gene polymorphism and essential hypertension in Madeira Island

PubMed Central

Sousa, Ana Célia; Palma dos Reis, Roberto; Pereira, Andreia; Borges, Sofia; Freitas, Ana Isabel; Guerra, Graça; Góis, Teresa; Rodrigues, Mariana; Henriques, Eva; Freitas, Sónia; Ornelas, Ilídio; Pereira, Décio; Brehm, António; Mendonça, Maria Isabel

2017-01-01

Abstract Essential hypertension (EH) is a complex disease in which physiological, environmental, and genetic factors are involved in its genesis. The genetic variant of the alpha-adducin gene (ADD1) has been described as a risk factor for EH, but with controversial results. The objective of this study was to evaluate the association of ADD1 (Gly460Trp) gene polymorphism with the EH risk in a population from Madeira Island. A case-control study with 1614 individuals of Caucasian origin was performed, including 817 individuals with EH and 797 controls. Cases and controls were matched for sex and age, by frequency-matching method. All participants collected blood for biochemical and genotypic analysis for the Gly460Trp polymorphism. We further investigated which variables were independently associated to EH, and, consequently, analyzed their interactions. In our study, we found a significant association between the ADD1 gene polymorphism and EH (odds ratio 2.484, P = .01). This association remained statistically significant after the multivariate analysis (odds ratio 2.548, P = .02). The ADD1 Gly460Trp gene polymorphism is significantly and independently associated with EH risk in our population. The knowledge of genetic polymorphisms associated with EH is of paramount importance because it leads to a better understanding of the etiology and pathophysiology of this pathology. PMID:29049185

Case-control study of infections with Salmonella enteritidis phage type 4 in England.

PubMed Central

Cowden, J. M.; Lynch, D.; Joseph, C. A.; O'Mahony, M.; Mawer, S. L.; Rowe, B.; Bartlett, C. L.

1989-01-01

OBJECTIVE--To determine the source of indigenous sporadic infection with Salmonella enteritidis phage type 4. DESIGN--Case-control study of primary sporadic cases identified by the Public Health Laboratory Service between 1 August and 30 September 1988. SETTING--PHLS Communicable Disease Surveillance Centre, Division of Enteric Pathogens, 11 PHLS laboratories, and 42 local authority environmental health departments in England. SUBJECTS--232 Patients (cases) with confirmed primary sporadic infection, for 160 of whom (88 female) (median age 30 years, age range 4 months to 85 years) data were obtained by questionnaire about consumption of fresh eggs, egg products, precooked chicken, and minced meat in the three days and one week before onset of the symptoms. Up to three controls, matched for neighbourhood, age, and sex (if aged greater than 11 years), were asked the same questions for the same calendar period. MAIN OUTCOME MEASURE--Association of primary sporadic infection with consumption of suspected food items. RESULTS--Illness due to S enteritidis phage type 4 was significantly associated with consumption of raw shell egg products (homemade mayonnaise, ice cream, and milk drinks containing eggs) (matched p = 0.02) and shop bought sandwiches containing mayonnaise (matched p = 0.00004) or eggs (matched p = 0.02). Illness was also significantly associated with eating lightly cooked eggs (unmatched p = 0.02), but not soft boiled eggs, and precooked hot chicken (matched p = 0.006). Reported consumption of eggs was not appreciably different between cases and controls before or after the median date of interview. CONCLUSIONS--Fresh shell eggs, egg products, and precooked hot chicken are vehicles of S enteritidis phage type 4 infection in indigenous sporadic cases. Public health education and reduction in contamination of eggs and infection of poultry with S enteritidis are needed to reduce the incidence of human infection. PMID:2508916

Dosimetric advantages of intensity-modulated proton therapy for oropharyngeal cancer compared with intensity-modulated radiation: A case-matched control analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Holliday, Emma B.; Kocak-Uzel, Esengul; Department of Radiation Therapy, Beykent University, Istanbul

A potential advantage of intensity-modulated proton therapy (IMPT) over intensity-modulated (photon) radiation therapy (IMRT) in the treatment of oropharyngeal carcinoma (OPC) is lower radiation dose to several critical structures involved in the development of nausea and vomiting, mucositis, and dysphagia. The purpose of this study was to quantify doses to critical structures for patients with OPC treated with IMPT and compare those with doses on IMRT plans generated for the same patients and with a matched cohort of patients actually treated with IMRT. In this study, 25 patients newly diagnosed with OPC were treated with IMPT between 2011 and 2012.more » Comparison IMRT plans were generated for these patients and for additional IMRT-treated controls extracted from a database of patients with OPC treated between 2000 and 2009. Cases were matched based on the following criteria, in order: unilateral vs bilateral therapy, tonsil vs base of tongue primary, T-category, N-category, concurrent chemotherapy, induction chemotherapy, smoking status, sex, and age. Results showed that the mean doses to the anterior and posterior oral cavity, hard palate, larynx, mandible, and esophagus were significantly lower with IMPT than with IMRT comparison plans generated for the same cohort, as were doses to several central nervous system structures involved in the nausea and vomiting response. Similar differences were found when comparing dose to organs at risks (OARs) between the IMPT cohort and the case-matched IMRT cohort. In conclusion, these findings suggest that patients with OPC treated with IMPT may experience fewer and less severe side effects during therapy. This may be the result of decreased beam path toxicities with IMPT due to lower doses to several dysphagia, odynophagia, and nausea and vomiting–associated OARs. Further study is needed to evaluate differences in long-term disease control and chronic toxicity between patients with OPC treated with IMPT in comparison to those treated with IMRT.« less

Using full-cohort data in nested case-control and case-cohort studies by multiple imputation.

PubMed

Keogh, Ruth H; White, Ian R

2013-10-15

In many large prospective cohorts, expensive exposure measurements cannot be obtained for all individuals. Exposure-disease association studies are therefore often based on nested case-control or case-cohort studies in which complete information is obtained only for sampled individuals. However, in the full cohort, there may be a large amount of information on cheaply available covariates and possibly a surrogate of the main exposure(s), which typically goes unused. We view the nested case-control or case-cohort study plus the remainder of the cohort as a full-cohort study with missing data. Hence, we propose using multiple imputation (MI) to utilise information in the full cohort when data from the sub-studies are analysed. We use the fully observed data to fit the imputation models. We consider using approximate imputation models and also using rejection sampling to draw imputed values from the true distribution of the missing values given the observed data. Simulation studies show that using MI to utilise full-cohort information in the analysis of nested case-control and case-cohort studies can result in important gains in efficiency, particularly when a surrogate of the main exposure is available in the full cohort. In simulations, this method outperforms counter-matching in nested case-control studies and a weighted analysis for case-cohort studies, both of which use some full-cohort information. Approximate imputation models perform well except when there are interactions or non-linear terms in the outcome model, where imputation using rejection sampling works well. Copyright © 2013 John Wiley & Sons, Ltd.

Impact of traumatic dental injury on the quality of life of young children: a case-control study.

PubMed

Vieira-Andrade, Raquel Gonçalves; Siqueira, Maria Betânia Lins; Gomes, Genara Brum; D'Avila, Sérgio; Pordeus, Isabela Almeida; Paiva, Saul Martins; Granville-Garcia, Ana Flávia

2015-10-01

There are no longitudinal studies that assess the impact of traumatic dental injury (TDI) on the oral health-related quality of life (OHRQoL) of preschool children. To investigate the impact of TDI on OHRQoL among preschool children, a population-based case-control study was carried out with a representative sample of 335 children, 3-5 years of age, enrolled at public and private preschools in the city of Campina Grande, Brazil. The case group and the control group were matched for age, gender, type of preschool and monthly household income at a ratio of 1:4 (67 cases and 286 controls). Impact on the OHRQoL of children was assessed through administration of the Early Childhood Oral Health Impact Scale (ECOHIS). The occurrence of TDI was determined through clinical examinations performed by three calibrated dentists. Data analysis involved descriptive statistics, McNemar's test, the chi-square test with linear trend and conditional logistic regression analysis [P≤0.05; 95% confidence interval (95% CI)]. The most frequent responses were 'felt pain' (19.4%) and 'difficulty eating' (16.4%). The prevalence of TDI was 37.3% in the case group and 33.9% in the control group. No statistically significant differences were found between case and control groups regarding the presence of TDI (odds ratio=1.16; 95% CI: 0.66-2.02). TDI had no impact on the quality of life of preschool children. © 2015 FDI World Dental Federation.

Anesthesia and Poliomyelitis: A Matched Cohort Study.

PubMed

Van Alstine, Luke W; Gunn, Paul W; Schroeder, Darrell R; Hanson, Andrew C; Sorenson, Eric J; Martin, David P

2016-06-01

Poliomyelitis is a viral infectious disease caused by 1 of the 3 strains of poliovirus. The World Health Organization launched an eradication campaign in 1988. Although the number of cases of poliomyelitis has drastically declined, eradication has not yet been achieved, and there are a substantial number of survivors of the disease. Survivors of poliomyelitis present a unique set of challenges to the anesthesiologist. The scientific literature regarding the anesthetic management of survivors of poliomyelitis, however, is limited and primarily experiential in nature. Using a retrospective, matched cohort study, we sought to more precisely characterize the anesthetic implications of poliomyelitis and to determine what risks, if any, may be present for patients with a history of the disease. Using the Mayo Clinic Life Sciences System Data Discovery and Query Builder, study subjects were identified as those with a history of paralytic poliomyelitis who had undergone major surgery at Mayo Clinic Rochester between 2005 and 2009. For each case, 2 sex- and age-matched controls that underwent the same surgical procedure during the study period were randomly selected from a pool of possible controls. Medical records were manually interrogated with respect to demographic variables, comorbid conditions, operative and anesthetic course, and postoperative course. We analyzed 100 cases with 2:1 matched controls and found that the peri- and postoperative courses were very similar for both groups of patients. Pain scores, postanesthesia care unit admission, length of postanesthesia care unit stay, intensive care unit admission, length of intensive care unit stay, and initial extubation location were not significantly different between the 2 groups. Looking at pulmonary complications in our primary outcome, there was no significant difference between the 2 groups (17% vs 14% for polio versus control, respectively; conditional logistic regression odds ratio = 1.5; 95% confidence interval, 0.7-3.3; P = 0.33). In addition, no difference was noted in those requiring a code or rapid response team intervention (4% vs 3% for polio versus control; P = 0.46) and the 30-day mortality rate was also not significantly different, with 2% of polio patients dying compared with 3% of controls (P = 0.79). The analysis of the primary outcome was repeated for the subset of patients with a history of poliomyelitis who had persistent neurologic deficits preoperatively (n = 36) and their matched controls (n = 72). In this subset analysis, there were 4 (11%) polio patients and 8 (11%) control patients who experienced pulmonary complications (conditional logistic regression odds ratio = 1.00; 95% confidence interval, 0.27-3.72; P = 1.00). The percentage of patients experiencing specific pulmonary complications of interest was similar between groups (postoperative mechanical ventilation: 6% vs 8% for polio and control patients, respectively; prolonged mechanical ventilation: 0% vs 1%; reintubation: 8% vs 4%; pulmonary infection: 6% vs 6%; and aspiration: 0% vs 1%). This study suggests that patients with a history of poliomyelitis do not seem to have an increased risk of pulmonary complications in the perioperative period. However, an odds ratio as great as 3.3-fold may be present.

Newspaper coverage of suicide and initiation of suicide clusters in teenagers in the USA, 1988-96: a retrospective, population-based, case-control study.

PubMed

Gould, Madelyn S; Kleinman, Marjorie H; Lake, Alison M; Forman, Judith; Midle, Jennifer Bassett

2014-06-01

Public health and clinical efforts to prevent suicide clusters are seriously hampered by the unanswered question of why such outbreaks occur. We aimed to establish whether an environmental factor-newspaper reports of suicide-has a role in the emergence of suicide clusters. In this retrospective, population-based, case-control study, we identified suicide clusters in young people aged 13-20 years in the USA from 1988 to 1996 (preceding the advent of social media) using the time-space Scan statistic. For each cluster community, we selected two matched non-cluster control communities in which suicides of similarly aged youth occurred, from non-contiguous counties within the same state as the cluster. We examined newspapers within each cluster community for stories about suicide published in the days between the first and second suicides in the cluster. In non-cluster communities, we examined a matched length of time after the matched control suicide. We used a content-analysis procedure to code the characteristics of each story and compared newspaper stories about suicide published in case and control communities with mixed-effect regression analyses. We identified 53 suicide clusters, of which 48 were included in the media review. For one cluster we could identify only one appropriate control; therefore, 95 matched control communities were included. The mean number of news stories about suicidal individuals published after an index cluster suicide (7·42 [SD 10·02]) was significantly greater than the mean number of suicide stories published after a non-cluster suicide (5·14 [6.00]; p<0·0001). Several story characteristics, including front-page placement, headlines containing the word suicide or a description of the method used, and detailed descriptions of the suicidal individual and act, appeared more often in stories published after the index cluster suicides than after non-cluster suicides. Our identification of an association between newspaper reports about suicide (including specific story characteristics) and the initiation of teenage suicide clusters should provide an empirical basis to support efforts by mental health professionals, community officials, and the media to work together to identify and prevent the onset of suicide clusters. US National Institute of Mental Health and American Foundation for Suicide Prevention. Copyright © 2014 Elsevier Ltd. All rights reserved.

Appendectomy, smoking habits and the risk of developing ulcerative colitis: a case control study in private practice setting.

PubMed

de Saussure, Philippe; Clerson, Pierre; Prost, Pierre-Louis; Truong Tan, Nghiep; Bouhnik, Yoram; Gil-Rch

2007-05-01

The strongest environmental factors identified for ulcerative colitis (UC) are cigarette smoking and appendectomy. However, most studies have been performed using case-controls from hospital-based populations. The purpose of this study was to compare the history of previous appendectomy and smoking habits in a group of patients with UC and a control group, followed by gastroenterologists in private practice. We performed a case control study in which 100 physicians recruited UC-patients and age and sex matched controls. Data were collected during a single visit. Based on a standardized questionnaire, UC patients and controls were divided into never, former or current smokers, and into subjects with or without a previous history of appendectomy. One hundred and ninety eight age- and sex-matched pairs of UC patients and controls were included. The prevalence of appendectomy in the UC-patients and control group was 12% and 46%, respectively. The pairwise-matched OR of ulcerative colitis for previous appendectomy was 0.10 (95% CI, 0.05-0.21) (P<0.0001). The OR for former and never smokers versus current smokers was 2.40 (95% CI 1.31-4.38) (P=0.004). In UC-patients, the OR of family history of UC compared with controls was 2.80 (95% CI, 1.01-7.77) (P=0.048). This case-control study confirmed a strong negative correlation between both appendectomy and tobacco smoking, and ulcerative colitis in patients followed-up by gastroenterological practitioners.

The HLA-matching effect in different cohorts of kidney transplant recipients: 10 years later.

PubMed

Sasaki, Nori; Idica, Adam

2010-01-01

Almost all the HLA-matching effects found by the 2000 analysis were confirmed by this study. The only HLA-matching effect found in the 2000 analysis that disappeared were those of "small matching effect" found in sub-populations of type I diabetes (PRA < 10%, donor age 20-35). The 2000 analysis found a lack of HLA matching effect in non-African American kidney transplant patients with type I diabetes between 1987 and 2000. The 2000 analysis found that a patients' ethnic group was a factor in graft survival; African American patients were found to have a significantly lower 10-year graft survival in the 5 or 6 mismatched group (27%) compared to Caucasian patients (40%). In addition, Asian patients (42%) had higher graft survival compared to that of Caucasian patients. In this study, we observe a similar pattern with death-censored graft analysis for all ethnic groups with 10-year graft survivals at 72.9% for Asians, 69.5% for Caucasians, and 49.3% for African Americans. There was an overall lack of HLA-matching effect on patient survival in the 2000 analysis. In our current analysis, the patient survivals remained virtually the same despite moderate increase in graft survival over the same period of time. The HLA-C locus mismatch was found to have additive effect to the 10-year graft survival trends observed in A and B mismatch cases. HLA-DQ mismatch on the other hand, showed limited HLA-matching effect and did not show the same additive effect as C. There are various possible issues in the DQ mismatch analysis, from the consistency of DQ typing results, lack of diversity in the DQ antigen, to the possibility of DQ mismatch having little effect on the graft survival. Utilizing kidney transplant cases performed from 1995 through 2000, the 2000 analysis projected 10-year survivals of 64% and 47% for the 0 ABDR mismatch and 5 or 6 ABDR mismatched cases respectively; the 2000 projection only missed actual death-censored survivals by 9% lower for the 0 mismatch and 17% lower for the 5 or 6 mismatch cases. Utilizing the transplant cases of 2005 through 2009, we projected their 10-year graft survivals for year 2020. The 10-year graft survival for 0 ABDR mismatched patients is expected to be over 85% and nearly 70% for 5 or 6 ABDR mismatched patients. The general upward trend of graft survival we have observed in the last 10 years has been dependent upon the development of novel transplant protocols and use of novel immunomodulatory reagents. This trend is likely to continue given the promise of new drugs and personalized healthcare. The decreasing range of the differences in the 10-year graft survival between best matched and worst matched HLA groups is also likely to continue. One interesting trend that is clearly evident is the increasing difference between the best and worst HLA-matching in terms of the associated graft half-life. The positive HLA-matching effect on long-term graft survival is clearly evident and should be taken into consideration for all kidney transplants.

Assessment of Lead Exposure Risk in Locksmiths

PubMed Central

Kondrashov, Vladislav; McQuirter, Joseph L.; Miller, Melba; Rothenberg, Stephen J.

2005-01-01

Exposure to lead has been well recognized in a number of work environments, but little is known about lead exposure associated with machining brass keys containing lead. The brass that is widely used for key manufacturing usually contains 1.5% – 2.5 % of lead. Six (6) licensed locksmiths and 6 case-matched controls successfully completed the pilot study to assess the prevalence of increased body lead burden of professional locksmiths. We measured both Blood Lead (atomic absorption spectrometry), bone-lead (KXRF) and had each subject complete a health and lead exposure risk questionnaire. One locksmith had not cut keys during the past two years, therefore this subject and case-matched control was excluded from the blood lead analysis only. The average blood-lead concentration (±SEM) for the 5 paired subjects was 3.1 (± 0.4) μg/dL and 2.2 (± 0.3) μg /dL for controls. Bone measurements, including all 6 paired subjects, showed tibia lead concentration (±SEM) for locksmiths and controls was 27.8 (± 2.3) μg /g and 13.7 (± 3.3) μg /g, respectively; average calcaneus lead concentration for locksmiths and controls was 31.9 (± 3.7) μg /g and 22.6 (± 4.1) μg /g, respectively: The t-test shows a significantly higher tibia lead (p<0.05) and blood lead (p<0.05) for locksmiths than for their matched controls, but no significant difference for calcaneus lead (p>0.10). Given that the mean tibia bone lead concentration was 13.1μg/g higher in locksmiths than in their matched controls, this average difference in the two groups would translate to an OR of increased hypertension in locksmiths of between 1.1 and 2.3, based on the published literature. Even with the very small number of subjects participating in this pilot study, we were able to demonstrate that locksmiths had significantly higher current exposure to lead (blood lead concentration) and significantly higher past exposure to lead (tibia lead concentration) than their age, sex and ethnically matched controls. Additional research is needed to fully identify the prevalence and associated risk factors for occupational exposure of lead in this previously understudied profession. PMID:16705814

Evaluating the use of friend or family controls in epidemiologic case-control studies.

PubMed

Zhong, Charlie; Cockburn, Myles; Cozen, Wendy; Voutsinas, Jenna; Lacey, James V; Luo, Jianning; Sullivan-Halley, Jane; Bernstein, Leslie; Wang, Sophia S

2017-02-01

Traditional methodologies for identifying and recruiting controls in epidemiologic case-control studies, such as random digit dialing or neighborhood walk, suffer from declining response rates. Here, we revisit the feasibility and comparability of using alternative sources of controls, specifically friend and family controls. We recruited from a recently completed case-control study of non-Hodgkin lymphoma (NHL) among women in Los Angeles County where controls from the parent study were ascertained by neighborhood walk. We calculated participation rates and compared questionnaire responses between the friend/family controls and the original matched controls from the parent study. Of the 182 NHL case patients contacted, 111 (61%) agreed to participate in our feasibility study. 70 (63%) provided contact information for potential friend and/or family member controls. We were able to successfully contact and recruit a friend/family member for 92% of the case patients. This represented 46 friend controls and 54 family controls. Family controls significantly differed from original matched controls by sex and household income. Other characteristics were similar between friend controls and the original study's neighborhood controls. The apparent comparability of neighborhood controls to friend and family controls among respondents in this study suggests that these alternative methods of control identification can serve as a complementary source of eligible controls in epidemiologic case-control studies. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Attitudes and Perception Towards Eye Donation in Patients with Corneal Disease: A Case-controlled Population-based Study.

PubMed

Noopur, Gupta; Praveen, Vashist; Radhika, Tandon; Sanjeev K, Gupta; Mani, Kalaivani; Deepak, Kumar

2018-06-01

To assess awareness, barriers, and misconceptions related to eye donation in people with corneal disease as compared to controls in a population setting. A population-based study was conducted in 25 randomly selected clusters of Rural Gurgaon, Haryana, India, as part of the CORE (Cornea Opacity Rural Epidemiological) study. In addition to ophthalmic examination, knowledge and perceptions regarding eye donation were assessed through a validated questionnaire. The questionnaire captured the sociodemographic factors influencing awareness regarding eye donation in participants with corneal disease and twice the number of age- and gender-matched controls recruited from the same study clusters. Descriptive statistics were computed along with multivariable logistic regression analysis to determine associated factors for awareness of eye donation. In the CORE study, 452 participants had corneal opacities on ocular examination. Of these, 442 were assessed for eye donation awareness. Additionally, 884 age- and gender-matched controls were recruited. The mean age of cases and controls was 60.9 ± 15.5 and 59.6 ± 14.3 years, respectively. Awareness of eye donation in cases and controls was 46.4% (n = 205 of 442) and 52.3% (n = 462 of 884), respectively (P = 0.044). Educational status was an important factor determining knowledge about eye donation in both cases and controls (P = < 0.001). Major barriers reported for not pledging eyes were lack of willingness (36.7%) and ignorance (15.3%). Common misconceptions like eyes could be donated before death or even after 24 h of death and that any type of blindness could be treated with corneal transplantation were prevalent. The study demonstrated that although there is substantial awareness about eye donation, there are numerous barriers in this population that need to be resolved to improve donation rates. Additional efforts are needed to translate this awareness into actual eye donation in both cases with corneal disease and controls.

Unique local bone tissue characteristics in iliac crest bone biopsy from adolescent idiopathic scoliosis with severe spinal deformity

PubMed Central

Wang, Zhiwei; Chen, Huanxiong; Yu, Y. Eric; Zhang, Jiajun; Cheuk, Ka-Yee; Ng, Bobby K. W.; Qiu, Yong; Guo, X. Edward; Cheng, Jack C. Y.; Lee, Wayne Y. W.

2017-01-01

Adolescent idiopathic scoliosis is a complex disease with unclear etiopathogenesis. Systemic and persistent low bone mineral density is an independent prognostic factor for curve progression. The fundamental question of how bone quality is affected in AIS remains controversy because there is lack of site-matched control for detailed analysis on bone-related parameters. In this case-control study, trabecular bone biopsies from iliac crest were collected intra-operatively from 28 severe AIS patients and 10 matched controls with similar skeletal and sexual maturity, anthropometry and femoral neck BMD Z-score to control confounding effects. In addition to static histomorphometry, micro-computed tomography (μCT) and real time-PCR (qPCR) analyses, individual trabecula segmentation (ITS)-based analysis, finite element analysis (FEA), energy dispersive X-ray spectroscopy (EDX) were conducted to provide advanced analysis of structural, mechanical and mineralization features. μCT and histomorphometry showed consistently reduced trabecular number and connectivity. ITS revealed predominant change in trabecular rods, and EDX confirmed less mineralization. The structural and mineralization abnormality led to slight reduction in apparent modulus, which could be attributed to differential down-regulation of Runx2, and up-regulation of Spp1 and TRAP. In conclusion, this is the first comprehensive study providing direct evidence of undefined unique pathological changes at different bone hierarchical levels in AIS. PMID:28054655

Evaluation of salivary tumor necrosis factor-alpha in patients with the chronic periodontitis: A case-control study.

PubMed

Yousefimanesh, Hojatollah; Maryam, Robati; Mahmoud, Jahangirnezhad; Mehri, Ghafourian Boroujerdnia; Mohsen, Taghipour

2013-11-01

Periodontitis is a chronic infectious disease that leads to inflammation of the tissues supporting the teeth, bone loss, attachment loss progressively. In chronic periodontitis for starting the host response and inflammatory reaction, the presence of the infectious agent is necessary. One of inflammatory factors is tumor necrosis factor-alpha (TNF-α) that appear to be important in the destruction of periodontal tissues that were examined in this study. This study was performed in the laboratory and case-control study. The samples of study collected from 30 individuals with chronic periodontitis and 30 healthy controls that matched for age and sex, together. Unstimulated saliva samples were collected from patients and then TNF-α level were measured by enzyme-linked immunosorbent assay and were compared with the control group. In this study for statistical analysis, Mann-Whitney was used. There were differences in mean salivary concentrations of TNF-α in controls and patients. The average concentration in the case group was 9.1 (pg/ml) and the control group was 8.7 (pg/ml), but there was no significant difference between case and control groups (P > 0.05). The results of this analysis showed no significant relationship between two groups TNF-α concentration. This biomarker can not seem to be a good index to evaluate or predict periodontal disease.

[Clinical and epidemiological differences between Bordetella pertussis and respiratory syncytial virus infections in infants: a matched case control study].

PubMed

Giménez-Sánchez, Francisco; Cobos-Carrascosa, Elena; Sánchez-Forte, Miguel; López-Sánchez, María Ángeles; González-Jiménez, Yolanda; Azor-Martínez, Ernestina

2014-01-01

An increase in cases of pertussis, mainly in young infants, has been reported in the last few years. The clinical presentation of this disease is very similar to that produced by respiratory syncytial virus (RSV), which makes the diagnosis difficult. To compare the clinical and epidemiological characteristics between Bordetella pertussis and RSV infections in infants admitted to hospital. An analytical matched case-control study was conducted during the period 2008-2011. Cases were defined as infants admitted with pertussis confirmed by PCR in nasopharyngeal aspirate. Each case was matched by age, sex and date of admission to two controls defined as patients with RSV infection detected by immunochromatography in nasal aspirate. Demographic, clinical, laboratory data were compared. Seventy eight patients (26 cases of pertussis and 52 controls RSV+) were included. Sociodemographic characteristics were similar in both groups. Cases had more days of symptoms prior to admission, longer hospital stays, and increased frequency of epidemic family environment. Apnoea and cyanosis were more frequent. Cases of pertussis were more likely to have apnoea, cyanosis, and lymphocytosis while RSV infections had more frequent fever, vomiting and respiratory distress. The clinical presentations of pertussis and RSV infection are similar, but there are some characteristics that can help to distinguish between them. Copyright © 2013 Elsevier España, S.L. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

Atrioventricular valve repair in patients with functional single-ventricle physiology: impact of ventricular and valve function and morphology on survival and reintervention.

PubMed

Honjo, Osami; Atlin, Cori R; Mertens, Luc; Al-Radi, Osman O; Redington, Andrew N; Caldarone, Christopher A; Van Arsdell, Glen S

2011-08-01

This study was to determine whether atrioventricular valve repair modifies natural history of single-ventricle patients with atrioventricular valve insufficiency and to identify factors predicting survival and reintervention. Fifty-seven (13.5%) of 422 single-ventricle patients underwent atrioventricular valve repair. Valve morphology, regurgitation mechanism, and ventricular morphology and function were analyzed for effect on survival, transplant, and reintervention with multivariate logistic and Cox regression models. Comparative analysis used case-matched controls. Atrioventricular valve was tricuspid in 67% and common in 28%. Ventricular morphology was right in 83%. Regurgitation mechanisms were prolapse (n = 24, 46%), dysplasia (n = 18, 35%), annular dilatation (n = 8, 15%), and restriction or cleft (n = 2, 4%). Postrepair insufficiency was none or trivial in 14 (26%), mild in 33 (61%), and moderate in 7 (13%). Survival in repair group was lower than in matched controls (78.9% vs 92.7% at 1 year, 68.7% vs 90.6% at 3 years, P = .015). Patients with successful repair and normal ventricular function had equivalent survival to matched controls (P = .36). Independent predictors for death or transplant included increased indexed annular size (P = .05), increased cardiopulmonary bypass time (P = .04), and decreased postrepair ventricular function (P = .01). Ventricular dilation was a time-related factor for all events, including failed repair. Survival was lower in single-ventricle patients operated on for atrioventricular valve insufficiency than in case-matched controls. Patients with little postoperative residual regurgitation and preserved ventricular function had equivalent survival to controls. Lower grade ventricular function and ventricular dilation correlated with death and repair failure, suggesting that timing of intervention may affect outcome. Copyright © 2011 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

Dermatoglyphics and Karyotype Analysis in Primary Amenorrhoea

PubMed Central

Sontakke, Bharat R; Waghmare, Jwalant E; Tarnekar, Aditya M; Shende, Moreshwar R; Pal, Asoke K

2014-01-01

Background: Dermatoglyphics is the scientific study of the skin ridge patterns on the fingers, toes, palms of the hands and soles of feet. Dermatoglyphics is in use as a supportive diagnostic tool in genetic or chromosomal disorders as well as in clinical conditions with genetic etiologies. Primary amenorrhoea and Dermatoglyphics, both have the suspected multifactorial (genetic and environmental) aetiologies. Objective: In the present study the finger dermatoglyphic patterns were studied in primary amenorrhoea cases and age matched fertile control females and also attention was given to find out whether a specific dermatoglyphic trait exists in primary amenorrhoea cases and whether it was statistically significant. Materials and Methods: To study the role of dermatoglyphics in primary amenorrhoea, a study was conducted on 30 subjects with primary amenorrhoea (as cases) and compared it with equal number of age matched fertile females (as controls). We studied fingertip patterns in all the subjects enrolled. Simultaneously we have assessed the Karyotype of primary amenorrhoea cases. Result and Conclusion: Two subjects in experimental group have shown abnormal Karyotypes. The most significant finding in present study was increased total finger ridge count (TFRC) in primary amenorrhoea cases which was statistically significant. We also found higher frequency of loops and arches in primary amenorrhoea with abnormal karyotypes. This type of study may be quite useful as a supportive investigation, in stating the predisposition of an individual to primary amenorrhoea and referral of an individual for karyotyping. PMID:25653930

Protective efficacy of BCG against leprosy in São Paulo.

PubMed

Lombardi, C; Pedrazzani, E S; Pedrazzani, J C; Filho, P F; Zicker, F

1996-03-01

The case-control study reported here evaluated the protective effect of BCG vaccine against leprosy in São Paulo, Brazil. Seventy-eight patients under age 16 who had been diagnosed as having leprosy (cases) and 385 healthy individuals (controls) were selected and matched by sex, age, place of residence, and type of exposure to leprosy (intradomiciliary or extradomiciliary). The cases were drawn from an active patient registry and from a group of new leprosy cases treated at 50 health centers in the cities of Bauru and Ribeirão Preto in the state of São Paulo. In order to estimate the protective effect of BCG, the prevalences of BCG scars in cases and controls were compared. The presence of one or more scars was associated with an estimated protective efficacy of 90% (95% confidence interval: 78% to 96%). Stratified analysis by age group, sex, socioeconomic level, and clinical form of the disease revealed no significant differences in the protection provided by the vaccine. However, it seems clear that more data will be needed in order to accurately assess the true relevance of BCG for leprosy control programs.

Modified metabolic syndrome and second cancers in women: A case control study.

PubMed

Ortiz-Mendoza, Carlos-Manuel; Pérez-Chávez, Ernesto; Fuente-Vera, Tania-Angélica De-la

2016-01-01

According to some studies, the metabolic syndrome causes diverse primary cancers; however, there is no evidence about metabolic syndrome impact on second cancers development in women. To find out the implication of the modified metabolic syndrome in women with second cancers. This was a case-control study, at a general hospital in Mexico City, in women with second cancers (cases) and age-matched women with only one neoplasm (controls). The analysis comprised: Tumor (s), anthropometric features, and body mass index (BMI); moreover, presence of diabetes mellitus, hypertension, and fasting serum levels of total cholesterol, triglycerides and glucose. The sample was of nine cases and 27 controls. In cases, the metabolic syndrome (diabetes mellitus or glucose > 99 mg/dL + hypertension or blood pressure ≥ 135/85 mm Hg + triglycerides > 149 mg/dL or BMI ≥ 30 kg/m 2 ) was more frequent (odds ratio 20.8, 95% confidence interval: 1.9-227.1). Our results suggest that in women, the modified metabolic syndrome may be a risk factor for second cancers.

Toxoplasma gondii Infection and Headache: A Matched Case-Control Study in a Public Hospital in Durango City, Mexico

PubMed Central

Alvarado-Esquivel, Cosme; Rico-Almochantaf, Yazmin del Rosario; Sanchez-Anguiano, Luis Francisco; Quinones-Canales, Gerardo; Hernandez-Tinoco, Jesus; Torres-Gonzalez, Jorge; Gonzalez-Silva, Maria Felix; Ramirez-Valles, Eda Guadalupe

2018-01-01

Background Toxoplasma gondii (T. gondii) can disseminate to brain in infected hosts. Little is known about the magnitude of the association between this infection and headache. Therefore, we sought to determine the association of T. gondii seropositivity and headache in patients attending neurological consultations in a public hospital in Durango City, Mexico. Methods Through an age- and gender-matched case-control study, 105 patients suffering from headache and 105 subjects without headache were examined for anti-T. gondii IgG and IgM antibodies using commercially available enzyme-linked immunoassays. Seropositive cases were analyzed for detection of T. gondii DNA by polymerase chain reaction. Results Anti-T. gondii IgG antibodies were found in five (4.8%) of the 105 cases and in seven (6.7%) of the 105 controls (odds ratio (OR) = 0.70; 95% confidence interval (CI): 0.21 - 2.28; P = 0.76). The frequency of high (> 150 IU/mL) levels of anti-T. gondii IgG antibodies among anti-T. gondii IgG positive individuals was significantly (P = 0.01) higher in cases (5/5) than in controls (1/7). Anti-T. gondii IgM antibodies were found in one (20.0%) of the five IgG seropositive cases, and in three (42.9%) of the seven IgG seropositive controls (P = 0.60). T. gondii DNA was not detected in any of the five anti-T. gondii IgG positive cases. No association between T. gondii infection and specific headache types was found. Conclusions This is the first matched case-control study on the association between T. gondii infection and headache. Results suggest that high anti-T. gondii IgG antibody levels, but not T. gondii seropositivity, were associated with headache in the population studied. PMID:29238431

Toxoplasma gondii Infection and Headache: A Matched Case-Control Study in a Public Hospital in Durango City, Mexico.

PubMed

Alvarado-Esquivel, Cosme; Rico-Almochantaf, Yazmin Del Rosario; Sanchez-Anguiano, Luis Francisco; Quinones-Canales, Gerardo; Hernandez-Tinoco, Jesus; Torres-Gonzalez, Jorge; Gonzalez-Silva, Maria Felix; Ramirez-Valles, Eda Guadalupe

2018-01-01

Toxoplasma gondii ( T. gondii ) can disseminate to brain in infected hosts. Little is known about the magnitude of the association between this infection and headache. Therefore, we sought to determine the association of T. gondii seropositivity and headache in patients attending neurological consultations in a public hospital in Durango City, Mexico. Through an age- and gender-matched case-control study, 105 patients suffering from headache and 105 subjects without headache were examined for anti- T. gondii IgG and IgM antibodies using commercially available enzyme-linked immunoassays. Seropositive cases were analyzed for detection of T. gondii DNA by polymerase chain reaction. Anti- T. gondii IgG antibodies were found in five (4.8%) of the 105 cases and in seven (6.7%) of the 105 controls (odds ratio (OR) = 0.70; 95% confidence interval (CI): 0.21 - 2.28; P = 0.76). The frequency of high (> 150 IU/mL) levels of anti- T. gondii IgG antibodies among anti- T. gondii IgG positive individuals was significantly (P = 0.01) higher in cases (5/5) than in controls (1/7). Anti- T. gondii IgM antibodies were found in one (20.0%) of the five IgG seropositive cases, and in three (42.9%) of the seven IgG seropositive controls (P = 0.60). T. gondii DNA was not detected in any of the five anti- T. gondii IgG positive cases. No association between T. gondii infection and specific headache types was found. This is the first matched case-control study on the association between T. gondii infection and headache. Results suggest that high anti- T. gondii IgG antibody levels, but not T. gondii seropositivity, were associated with headache in the population studied.

Primary health care utilization prior to suicide: a retrospective case-control study among active-duty military personnel.

PubMed

Hochman, Eldar; Shelef, Leah; Mann, J John; Portugese, Shirly; Krivoy, Amir; Shoval, Gal; Weiser, Mark; Fruchter, Eyal

2014-08-01

About 45% of civilians who died by suicide had contact with a doctor within 1 month of death. Thus, educating primary care physicians (PCP) to detect and mitigate depression is an important suicide-prevention strategy. However, the PCP consulting rate before suicide has not been examined in a military population. We investigated the utilization of primary health care and mental health services by active-duty military personnel suicide cases prior to death in comparison to matched military controls. All suicides (N = 170) were extracted from a cohort of all active-duty Israeli military male personnel between 2002 and 2012. Applying a retrospective, nested case-control design, we compared primary care services utilization by suicide cases with demographic and occupationally matched military controls (N = 500). Whereas 38.3% of suicide cases contacted a PCP within the last month before death, only 27.6% of suicide cases contacted a mental health specialist during their entire service time. The PCP contact rate within 1 month before death or index day did not differ between suicide cases and military controls (38.3% vs. 33.8%, χ²₁ = 1.05, P = .3). More suicide cases contacted a mental health specialist within service time than did military controls (27.6% vs. 13.6%, χ²₁ = 10.85, P = .001). Even though PCP contact rate by military personnel who died by suicide is slightly lower than that reported for civilians who died by suicide prior to their death, it is higher than mental health specialist contact rate and higher than that by age-matched civilians who died by suicide. These results imply that PCPs education is a viable approach to suicide prevention in a military setting. © Copyright 2014 Physicians Postgraduate Press, Inc.

Mediastinal micro-vessels clipping during lymph node dissection may contribute to reduce postoperative pleural drainage

PubMed Central

Yan, Shi; Wang, Xing; Lv, Chao; Phan, Kevin; Wang, Yuzhao; Wang, Jia; Yang, Yue

2016-01-01

Background Postoperative pleural drainage markedly influences the length of postoperative stay and financial costs of medical care. The aim of this study is to retrospectively investigate potentially predisposing factors related to pleural drainage after curative thoracic surgery and to explore the impact of mediastinal micro-vessels clipping on pleural drainage control after lymph node dissection. Methods From February 2012 to November 2013, 322 consecutive cases of operable non-small cell lung cancers (NSCLC) undergoing lobectomy and mediastinal lymph node dissection with or without application of clipping were collected. Total and daily postoperative pleural drainage were recorded. Propensity score matching (1:2) was applied to balance variables potentially impacting pleural drainage between group clip and group control. Analyses were performed to compare drainage volume, duration of chest tube and postoperative hospital stay between the two groups. Variables linked with pleural drainage in whole cohort were assessed using multivariable logistic regression analysis. Results Propensity score matching resulted in 197 patients (matched cohort). Baseline patient characteristics were matched between two groups. Group clip showed less cumulative drainage volume (P=0.020), shorter duration of chest tube (P=0.031) and postoperative hospital stay (P=0.022) compared with group control. Risk factors significantly associated with high-output drainage in multivariable logistic regression analysis were being male, age >60 years, bilobectomy/sleeve lobectomy, pleural adhesion, the application of clip applier, duration of operation ≥220 minutes and chylothorax (P<0.05). Conclusions This study suggests that mediastinal micro-vessels clipping during lymph node dissection may reduce postoperative pleural drainage and thus shorten hospital stay. PMID:27076936

USING MICROSOFT OFFICE EXCEL® 2007 TO CONDUCT GENERALIZED MATCHING ANALYSES

PubMed Central

Reed, Derek D

2009-01-01

The generalized matching equation is a robust and empirically supported means of analyzing relations between reinforcement and behavior. Unfortunately, no simple task analysis is available to behavior analysts interested in using the matching equation to evaluate data in clinical or applied settings. This technical article presents a task analysis for the use of Microsoft Excel to analyze and plot the generalized matching equation. Using a data-based case example and a step-by-step guide for completing the analysis, these instructions are intended to promote the use of quantitative analyses by researchers with little to no experience in quantitative analyses or the matching law. PMID:20514196

Using Microsoft Office Excel 2007 to conduct generalized matching analyses.

PubMed

Reed, Derek D

2009-01-01

The generalized matching equation is a robust and empirically supported means of analyzing relations between reinforcement and behavior. Unfortunately, no simple task analysis is available to behavior analysts interested in using the matching equation to evaluate data in clinical or applied settings. This technical article presents a task analysis for the use of Microsoft Excel to analyze and plot the generalized matching equation. Using a data-based case example and a step-by-step guide for completing the analysis, these instructions are intended to promote the use of quantitative analyses by researchers with little to no experience in quantitative analyses or the matching law.

Nitrates in drinking water and risk of death from rectal cancer in Taiwan.

PubMed

Kuo, Hsin-Wei; Wu, Trong-Neng; Yang, Chun-Yuh

2007-10-01

The relationship between nitrate levels in drinking water and rectal cancer development has been inconclusive. A matched case-control and nitrate ecology study was used to investigate the association between mortality attributed to rectal cancer and drinking-water nitrate exposure in Taiwan. All deaths due to rectal cancer of Taiwan residents from 1999 through 2003 were obtained from the Bureau of Vital Statistics of the Taiwan Provincial Department of Health. Controls were deaths from other causes and were pair matched to the cancer cases by gender, year of birth, and year of death. Each matched control was selected randomly from the set of possible controls for each case. Data on nitrate-nitrogen (NO3-N) levels in drinking water throughout Taiwan were collected from Taiwan Water Supply Corporation (TWSC). The municipality of residence for cancer cases and controls was assumed to be the source of the subject's nitrate exposure via drinking water. The adjusted odds ratios for rectal cancer death for those with high nitrate levels in their drinking water, as compared to the lowest tertile, were 1.22 (0.98-1.52) and 1.36 (1.08-1.70), respectively. The findings of this study warrant further investigation of the role of nitrates in drinking water in the etiology of rectal cancer in Taiwan.

Effectiveness of the 10-Valent Pneumococcal Conjugate Vaccine (PCV-10) in Children in Chile: A Nested Case-Control Study Using Nationwide Pneumonia Morbidity and Mortality Surveillance Data

PubMed Central

Toscano, Cristiana M.; Alencar, Gizelton P.; Alvarez, Andrés; Valenzuela, Maria T.; Andrus, Jon; del Aguila, Roberto; Hormazábal, Juan C.; Araya, Pamela; Pidal, Paola; Matus, Cuauhtemoc R.; de Oliveira, Lucia H.

2016-01-01

Background The ten-valent pneumococcal conjugate vaccine (PCV10) was introduced into the Chilean National Immunization Program (NIP) in January 2011 with a 3+1 schedule (2, 4, 6 and 12 months) without catch-up vaccination. We evaluated the effectiveness of PCV10 on pneumonia morbidity and mortality among infants during the first two years after vaccine introduction. Methods This is a population-based nested case-control study using four merged nationwide case-based electronic health data registries: live birth, vaccination, hospitalization and mortality. Children born in 2010 and 2011 were followed from two moths of age for a period of two years. Using four different case definitions of pneumonia hospitalization and/or mortality (all-cause and pneumonia related deaths), all cases and four randomly selected matched controls per case were selected. Controls were matched to cases on analysis time. Vaccination status was then assessed. Vaccine effectiveness (VE) was estimated using conditional logistic regression. Results There were a total of 497,996 children in the 2010 and 2011 Chilean live-birth cohorts. PCV10 VE was 11.2% (95%CI 8.5–13.6) when all pneumonia hospitalizations and deaths were used to define cases. VE increased to 20.7 (95%CI 17.3–23.8) when ICD10 codes used to denote viral pneumonia were excluded from the case definition. VE estimates on pneumonia deaths and all-cause deaths were 71.5 (95%CI 9.0–91.8) and 34.8 (95% CI 23.7–44.4), respectively. Conclusion PCV10 vaccination substantially reduced the number of hospitalizations due to pneumonia and deaths due to pneumonia and to all-causes over this study period. Our findings also reinforce the importance of having quality health information systems for measuring VE. PMID:27058873

ICU telemedicine and critical care mortality: a national effectiveness study

PubMed Central

Kahn, Jeremy M; Le, Tri Q.; Barnato, Amber E.; Hravnak, Marilyn; Kuza, Courtney C.; Pike, Francis; Angus, Derek C.

2015-01-01

Background Intensive care unit (ICU) telemedicine is an increasingly common strategy for improving the outcome of critical care, but its overall impact is uncertain. Objectives To determine the effectiveness of ICU telemedicine in a national sample of hospitals and quantify variation in effectiveness across hospitals. Research design We performed a multi-center retrospective case-control study using 2001–2010 Medicare claims data linked to a national survey identifying United States hospitals adopting ICU telemedicine. We matched each adopting hospital (cases) to up to 3 non-adopting hospitals (controls) based on size, case-mix and geographic proximity during the year of adoption. Using ICU admissions from 2 years before and after the adoption date, we compared outcomes between case and control hospitals using a difference-in-differences approach. Results 132 adopting case hospitals were matched to 389 similar non-adopting control hospitals. The pre- and post-adoption unadjusted 90-day mortality was similar in both case hospitals (24.0% vs. 24.3%, p=0.07) and control hospitals (23.5% vs. 23.7%, p<0.01). In the difference-in-differences analysis, ICU telemedicine adoption was associated with a small relative reduction in 90-day mortality (ratio of odds ratios: 0.96, 95% CI = 0.95–0.98, p<0.001). However, there was wide variation in the ICU telemedicine effect across individual hospitals (median ratio of odds ratios: 1.01; interquartile range 0.85–1.12; range 0.45–2.54). Only 16 case hospitals (12.2%) experienced statistically significant mortality reductions post-adoption. Hospitals with a significant mortality reduction were more likely to have large annual admission volumes (p<0.001) and be located in urban areas (p=0.04) compared to other hospitals. Conclusions Although ICU telemedicine adoption resulted in a small relative overall mortality reduction, there was heterogeneity in effect across adopting hospitals, with large-volume urban hospitals experiencing the greatest mortality reductions. PMID:26765148

Occupational risk factors for Wilms' tumor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bunin, G.; Kramer, S.; Nass, C.

A matched case-control study of Wilms' tumor investigated parental occupational risk factors. Cases diagnosed in 1970-1983 were identified through a population-based tumor registry and hospital registries in the Greater Philadelphia area. Controls were selected by random digit dialing and were matched to cases on race, birth date (+/- 3 years), and the area code and exchange of the case's telephone number at diagnosis. Parents of 100 matched pairs were interviewed by telephone. Parents of patients and controls were generally similar in demographic characteristics, except that mothers differed in religion. Published schemes were used to group jobs into clusters of similarmore » exposures and to determine exposures from industry and job title. Analyses were done for preconception, pregnancy, and postnatal time periods. More case than control fathers had jobs in a cluster that includes machinists and welders (odds ratios (ORs) = 4.0-5.7, p less than or equal to 0.04). Paternal exposures to lead, silver, tin, and iron (some exposures of this cluster) were associated with Wilms' tumor in some analyses, with moderate odds ratios (ORs = 1.5-3.4). In general, the highest odds ratios were found for the preconception period among the genetic (prezygotic) cases. No maternal job clusters or exposures gave significantly elevated odds ratios. These results support a previous finding that lead is a risk factor, but not radiation, hydrocarbon, or boron exposures.« less

Impact of the viral respiratory season on postoperative outcomes in children undergoing cardiac surgery.

PubMed

Spaeder, Michael C; Carson, Kathryn A; Vricella, Luca A; Alejo, Diane E; Holmes, Kathryn W

2011-08-01

To compare postoperative outcomes in children undergoing cardiac surgery during the viral respiratory season and nonviral season at our institution. This was a retrospective cohort study and secondary matched case-control analysis. The setting was an urban academic tertiary-care children's hospital. The study was comprised of all patients <18 years of age who underwent cardiac surgery at Johns Hopkins Hospital from October 2002 through September 2007. Patients were stratified by season of surgery, complexity of cardiac disease, and presence or absence of viral respiratory infection. Measurements included patient characteristics and postoperative outcomes. The primary outcome was postoperative length of stay (LOS). A total of 744 patients were included in the analysis. There was no difference in baseline characteristics or outcomes, specifically, no difference in postoperative LOS, intensive care unit (ICU) LOS, and mortality, among patients by seasons of surgery. Patients with viral respiratory illness were more likely to have longer postoperative LOS (p < 0.01) and ICU LOS (p < 0.01) compared with matched controls. We identified no difference in postoperative outcomes based on season in patients undergoing cardiac surgery. Children with viral respiratory infection have significantly worse outcomes than matched controls, strengthening the call for universal administration of influenza vaccination and palivizumab to appropriate groups. Preoperative testing for respiratory viruses should be considered during the winter months for children undergoing elective cardiac surgery.

Nutrient intake and gastric cancer risk: a case-control study in Spain.

PubMed

Ramón, J M; Serra-Majem, L; Cerdó, C; Oromí, J

1993-12-01

A case-control study of dietary factors and gastric cancer was conducted between September 1986 and March 1989 in the Barcelona metropolitan area, Spain. In all 117 cases with histologically confirmed diagnosis of gastric adenocarcinoma were matched on sex, age and possession of a telephone to 234 population controls. Of the controls 188 (80.3%) were selected by random digit telephone dialing and 46 (19.7%) by neighbourhood of residence. Information about frequency and amount of consumption of 89 alimentary items was gathered by questionnaire, and cases and controls were interviewed in their homes by trained interviewers. The gastric cancer risk decreased in proportion to vitamin C intake. In multivariate analysis adjusting for major covariables, energy and vitamin A intake, the estimated odds ratio (OR) for the upper quartile of vitamin C intake was 0.3 (95% confidence interval [CI]: 0.1-0.8). After adjustment for major covariables, calories and vitamin C intake, vitamin A did not show significant association with the gastric cancer risk. Our findings are consistent with previous case-control studies and with the hypothesis that vitamin C may inhibit the intragastric nitrosation process.

Risk factors, clinical features, and outcomes of toxoplasmosis in solid-organ transplant recipients: a matched case-control study.

PubMed

Fernàndez-Sabé, Núria; Cervera, Carlos; Fariñas, M Carmen; Bodro, Marta; Muñoz, Patricia; Gurguí, Mercè; Torre-Cisneros, Julián; Martín-Dávila, Pilar; Noblejas, Ana; Len, Oscar; García-Reyne, Ana; Del Pozo, José Luis; Carratalà, Jordi

2012-02-01

Solid-organ transplant (SOT) recipients are considered to be at increased risk for toxoplasmosis. However, risk factors for this infection have not been assessed. The aim of this study was to determine the risk factors, clinical features, and outcomes of toxoplasmosis in SOT recipients. A multicenter, matched case-control study (1:2 ratio) was conducted between 2000 and 2009. Control subjects were matched for center, transplant type, and timing. Cases were identified from the hospitals' microbiology and transplantation program databases. Logistic regression was performed to identify independent risk factors. Twenty-two cases (0.14%) of toxoplasmosis were identified among 15 800 SOTs performed in 11 Spanish hospitals, including 12 heart, 6 kidney, and 4 liver recipients. Diagnosis was made by seroconversion (n = 17), histopathologic examination (n = 5), polymerase chain reaction (n = 2), and autopsy (n = 2). In a comparison of case patients with 44 matched control subjects, a negative serostatus prior to transplantation was the only independent risk factor for toxoplasmosis (odds ratio, 15.12 [95% confidence interval, 2.37-96.31]; P = .004). The median time to diagnosis following transplantation was 92 days. Primary infection occurred in 18 (81.8%) cases. Manifestations included pneumonitis (n = 7), myocarditis (n = 5), brain abscesses (n = 5), chorioretinitis (n = 3), lymph node enlargement (n = 2), hepatosplenomegaly (n = 2), and meningitis (n =1). Five patients (22.7%) had disseminated disease. Crude mortality rate was 13.6% (3 of 22 patients). Although uncommon, toxoplasmosis in SOT patients causes substantial morbidity and mortality. Seronegative recipients are at high risk for developing toxoplasmosis and should be given prophylaxis and receive careful follow-up.

Sleepiness/fatigue and distraction/inattention as factors for fatal versus nonfatal commercial motor vehicle driver injuries.

PubMed

Bunn, T L; Slavova, S; Struttmann, T W; Browning, S R

2005-09-01

A retrospective population-based case-control study was conducted to determine whether driver sleepiness/fatigue and inattention/distraction increase the likelihood that a commercial motor vehicle collision (CVC) will be fatal. Cases were identified as CVC drivers who died (fatal) and controls were drivers who survived (nonfatal) an injury collision using the Kentucky Collision Report Analysis for Safer Highways (CRASH) electronic database from 1998-2002. Cases and controls were matched on unit type and roadway type. Conditional logistic regression was performed. Driver sleepiness/fatigue, distraction/inattention, age of 51 years of age and older, and nonuse of safety belts increase the odds that a CVC will be fatal. Primary safety belt law enactment and enforcement for all states, commercial vehicle driver education addressing fatigue and distraction and other approaches including decreased hours-of-service, rest breaks and policy changes, etc. may decrease the probability that a CVC will be fatal.

Short Report: Lack of Evidence of Hepatitis C and HIV Co-Infection among Men Who Have Sex with Men in Peru

PubMed Central

Lama, Javier R.; Lucchetti, Aldo; Cabezas, Cesar; Suarez-Ognio, Luis; Sanchez, Jorge

2012-01-01

Hepatitis C virus (HCV) infection occurs among human immunodeficiency virus (HIV)-infected men who have sex with men (MSM) because of shared routes of transmission. To assess the association between HCV and HIV infection among MSM in Peru, we conducted a matched case-control study (162 HIV-positive cases and 324 HIV-negative controls) among participants of an HIV sentinel surveillance survey in six urban cities. The HCV infection was initially screened using anti-HCV ELISA and immunoblot assay, and thereafter confirmed by the HCV RNA qualitative assay. Among cases, no confirmed HCV infection was found while among controls, only two confirmed HCV infections were reported (0.62%). This matched case-control reports a very low probability of association between HCV and HIV co-infection and suggests a very low prevalence of HCV infection among MSM in Peru. PMID:19556587

[Lack of association between MMR vaccination and the incidence of autism in children: a case-control study].

PubMed

Mrozek-Budzyn, Dorota; Kiełtyka, Agnieszka; Majewska, Renata

2009-01-01

The matched case-control study has been undertook to investigate whether measles, mumps, and rubella (MMR) vaccine may be casually associated with autism in children. Cases were children to 14-year old with diagnosis of core autism or atypical autism. Controls were matched on age, sex and general practice. The 96 cases and 192 controls were included. The study provides strong evidence against association of autism with both MMR and a single measles individual vaccine. Additionally children vaccinated with MMR, regardless of age of vaccination (to 18th, 24th and 36th month of life), had risk equal half of that of single measles vaccinated (for vaccinated to 18th month OR=0.41 95%PU: 0.20-0.85). Our findings confirm that MMR vaccination is not associated with an increased risk of autism in children.

Circulatory nucleosome levels are significantly increased in early and late-onset preeclampsia.

PubMed

Zhong, Xiao Yan; Gebhardt, Stefan; Hillermann, Renate; Tofa, Kashefa Carelse; Holzgreve, Wolfgang; Hahn, Sinuhe

2005-08-01

Elevations in circulatory DNA, as measured by real-time PCR, have been observed in pregnancies with manifest preeclampsia. Recent reports have indicated that circulatory nucleosome levels are elevated in the periphery of cancer patients. We have now examined whether circulatory nucleosome levels are similarly elevated in cases with preeclampsia. Maternal plasma samples were prepared from 17 cases with early onset preeclampsia (<34 weeks gestation) with 14 matched normotensive controls, as well as 15 cases late-onset preeclampsia (>34 weeks gestation) with 10 matched normotensive controls. Levels of circulatory nucleosomes were quantified by commercial ELISA (enzyme-linked immunosorbant assay). The level of circulatory nucleosomes was significantly elevated in both study preeclampsia groups, compared to the matched normotensive control group (p = 0.000 and p = 0.001, respectively). Our data suggests that preeclampsia is associated with the elevated presence of circulatory nucleosomes, and that this phenomenon occurs in both early- and late-onset forms of the disorder. Copyright 2005 John Wiley & Sons, Ltd.

Bayes and empirical Bayes methods for reduced rank regression models in matched case-control studies.

PubMed

Satagopan, Jaya M; Sen, Ananda; Zhou, Qin; Lan, Qing; Rothman, Nathaniel; Langseth, Hilde; Engel, Lawrence S

2016-06-01

Matched case-control studies are popular designs used in epidemiology for assessing the effects of exposures on binary traits. Modern studies increasingly enjoy the ability to examine a large number of exposures in a comprehensive manner. However, several risk factors often tend to be related in a nontrivial way, undermining efforts to identify the risk factors using standard analytic methods due to inflated type-I errors and possible masking of effects. Epidemiologists often use data reduction techniques by grouping the prognostic factors using a thematic approach, with themes deriving from biological considerations. We propose shrinkage-type estimators based on Bayesian penalization methods to estimate the effects of the risk factors using these themes. The properties of the estimators are examined using extensive simulations. The methodology is illustrated using data from a matched case-control study of polychlorinated biphenyls in relation to the etiology of non-Hodgkin's lymphoma. © 2015, The International Biometric Society.

Risk factors of post-traumatic stress disorder (PTSD) after Wenchuan earthquake: a case control study.

PubMed

Cheng, Yongzhong; Wang, Fang; Wen, Jin; Shi, Yingkang

2014-01-01

Few clues were found in the literature about the independent risk factors for PTSD among earthquake survivors in Sichuan province three years after the 2008 earthquake. Ours was the first case-control study with matching factors of age and distance from the epicenter among survivors age 16 years or older, three years after the catastrophe. To identify independent risk factors for PTSD among earthquake survivors. We performed a population-based matched case-control study. The cases were drawn from earthquake areas three years after the Wenchuan earthquake, including 113 cases who met positive criteria for PTSD symptoms according to the PCL-C (PTSD Checklist-Civilian Version) score and 452 controls who did not meet the criteria. Cases and controls were matched individually by birth year (+ three years) and the town they lived in when the earthquake occurred. Independent risk factors for PTSD symptoms included two-week disease prevalence (odds ratio [OR],1.92; 95% confidence interval [CI],1.18-3.13), witnessing someone being killed in the earthquake (OR, 2.04;95%CI, 1.17-3.58), having no regular income after the earthquake (OR, 0.52; 95%CI, 0.28-0.98), receiving mental health support only one time after the earthquake (OR, 2.43; 95%CI, 1.09-5.42) and lower social support (lower PSSS score) (OR, 0.95; 95%CI, 0.93-0.97). Earthquake experience, suffering from physical illnesses, lack of stable income, and lower social support were associated with PTSD symptoms.

Escherichia coli O157:H7 outbreak associated with consumption of ground beef, June-July 2002.

PubMed

Vogt, Richard L; Dippold, Laura

2005-01-01

A case-control and environmental study tested the hypothesis that purchasing and eating ground beef from a specific source was the cause of a cluster of cases of hemolytic uremic syndrome (HUS) and Escherichia coli (E. coli) O157:H7 gastroenteritis. A case-control study comparing risk factors was conducted over the telephone on nine case-patients with 23 selected controls. An environmental investigation was conducted that consisted of reviewing beef handling practices at a specific local supermarket and obtaining ground beef samples from the store and two households with case-patients. The analysis of the case-control study showed that eight case-patients (89%) purchased ground beef at Grocery Chain A compared with four controls who did not develop illness (17%) (matched odds ratio=undefined; 95% confidence interval 2.8, infinity; p=0.006). The environmental investigation showed that Grocery Chain A received meat from Meatpacker A. Laboratory analysis of meat samples from Meatpacker A and Grocery Chain A and stool samples from some patients recovered an identical strain of E. coli O157:H7 according to pulse-field gel electrophoresis. Both the case-control and environmental studies showed that purchasing ground beef at Grocery Chain A, which received ground beef from Meatpacker A, was the major risk factor for illness in eight case-patients; the ninth case-patient was found to be unrelated to the outbreak. Furthermore, meat from Meatpacker A was associated with a nationwide outbreak of E. coli O157:H7 illness that resulted in the second largest recall of beef in U.S. history at the time.

Longitudinal Analysis of the Premature Infant Intestinal Microbiome Prior to Necrotizing Enterocolitis: A Case-Control Study

PubMed Central

Zhou, Yanjiao; Shan, Gururaj; Sodergren, Erica; Weinstock, George; Walker, W. Allan; Gregory, Katherine E.

2015-01-01

Necrotizing enterocolitis (NEC) is an inflammatory disease of the newborn bowel, primarily affecting premature infants. Early intestinal colonization has been implicated in the pathogenesis of NEC. The objective of this prospective case-control study was to evaluate differences in the intestinal microbiota between infants who developed NEC and unaffected controls prior to disease onset. We conducted longitudinal analysis of the 16S rRNA genes of 312 samples obtained from 12 NEC cases and 26 age-matched controls with a median frequency of 7 samples per subject and median sampling interval of 3 days. We found that the microbiome undergoes dynamic development during the first two months of life with day of life being the major factor contributing to the colonization process. Depending on when the infant was diagnosed with NEC (i.e. early vs. late onset), the pattern of microbial progression was different for cases and controls. The difference in the microbiota was most overt in early onset NEC cases and controls. In proximity to NEC onset, the abundances of Clostridium sensu stricto from Clostridia class were significantly higher in early onset NEC subjects comparing to controls. In late onset NEC, Escherichia/Shigella among Gammaproteobacteria, showed an increasing pattern prior to disease onset, and was significantly higher in cases than controls six days before NEC onset. Cronobacter from Gammaproteobacteria was also significantly higher in late onset NEC cases than controls 1-3 days prior to NEC onset. Thus, the specific infectious agent associated with NEC may vary by the age of infant at disease onset. We found that intravenously administered antibiotics may have an impact on the microbial diversity present in fecal material. Longitudinal analysis at multiple time points was an important strategy utilized in this study, allowing us to appreciate the dynamics of the premature infant intestinal microbiome while approaching NEC at various points. PMID:25741698

Outcomes of Arthroscopic Rotator Cuff Repair in Patients Who Are 70 Years of Age or Older Versus Under 70 Years of Age: A Sex- and Tear Size-Matched Case-Control Study.

PubMed

Gwark, Ji-Yong; Sung, Chang-Meen; Na, Jae-Boem; Park, Hyung Bin

2018-05-19

To compare the structural and clinical outcomes after arthroscopic rotator cuff repair (ARCR) of a case group aged 70 and above with those of a control group younger than 70, with the 2 groups matched for sex and tear size. The case group, comprising 53 patients 70 or older, and the control group, comprising 159 patients younger than 70, all received ARCR to 1 shoulder with symptomatic full-thickness rotator cuff tear. The case and the control subjects, who were matched for sex and tear size to minimize bias related to tendon healing, received ARCR during the same period. The mean age was 71.8 ± 2.6 years in the case group and 59.3 ± 7.1 years in the control group. The minimum follow-up period was 1 year in both groups. Cuff integrity was evaluated using ultrasonography. Structural and clinical outcomes of the 2 groups were compared. Regarding structural outcomes, the complete healing, partial-thickness retear, and full-thickness retear rates were 66% (35/53), 15% (8/53), and 19% (10/53) in the case group, and 68% (108/159), 19% (30/159), and 13% (21/159), respectively, in the control group. The 2 groups had no significantly different retear rates (P = .52). Regarding clinical outcomes, the mean improvements in range of motion, pain, muscle strength, and age- and sex-matched Constant scores were not significantly different between the 2 groups (P > .37). The preoperative tear size was significantly associated with retear in both studied groups (P = .02). The clinical and structural outcomes of ARCR in patients 70 or older with symptomatic full-thickness rotator cuff tear are comparable with those in patients younger than 70 with at least 1-year follow-up. Preoperative tear size, a biological factor, is a strong predictor for retear. Level III, a retrospective comparative (case-control) study. Copyright © 2018 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

Isavuconazole treatment for mucormycosis: a single-arm open-label trial and case-control analysis.

PubMed

Marty, Francisco M; Ostrosky-Zeichner, Luis; Cornely, Oliver A; Mullane, Kathleen M; Perfect, John R; Thompson, George R; Alangaden, George J; Brown, Janice M; Fredricks, David N; Heinz, Werner J; Herbrecht, Raoul; Klimko, Nikolai; Klyasova, Galina; Maertens, Johan A; Melinkeri, Sameer R; Oren, Ilana; Pappas, Peter G; Ráčil, Zdeněk; Rahav, Galia; Santos, Rodrigo; Schwartz, Stefan; Vehreschild, J Janne; Young, Jo-Anne H; Chetchotisakd, Ploenchan; Jaruratanasirikul, Sutep; Kanj, Souha S; Engelhardt, Marc; Kaufhold, Achim; Ito, Masanori; Lee, Misun; Sasse, Carolyn; Maher, Rochelle M; Zeiher, Bernhardt; Vehreschild, Maria J G T

2016-07-01

Mucormycosis is an uncommon invasive fungal disease with high mortality and few treatment options. Isavuconazole is a triazole active in vitro and in animal models against moulds of the order Mucorales. We assessed the efficacy and safety of isavuconazole for treatment of mucormycosis and compared its efficacy with amphotericin B in a matched case-control analysis. In a single-arm open-label trial (VITAL study), adult patients (≥18 years) with invasive fungal disease caused by rare fungi, including mucormycosis, were recruited from 34 centres worldwide. Patients were given isavuconazole 200 mg (as its intravenous or oral water-soluble prodrug, isavuconazonium sulfate) three times daily for six doses, followed by 200 mg/day until invasive fungal disease resolution, failure, or for 180 days or more. The primary endpoint was independent data review committee-determined overall response-ie, complete or partial response (treatment success) or stable or progressive disease (treatment failure)-according to prespecified criteria. Mucormycosis cases treated with isavuconazole as primary treatment were matched with controls from the FungiScope Registry, recruited from 17 centres worldwide, who received primary amphotericin B-based treatment, and were analysed for day-42 all-cause mortality. VITAL is registered with ClinicalTrials.gov, number NCT00634049. FungiScope is registered with ClinicalTrials.gov, number NCT01731353. Within the VITAL study, from April 22, 2008, to June 21, 2013, 37 patients with mucormycosis received isavuconazole for a median of 84 days (IQR 19-179, range 2-882). By day 42, four patients (11%) had a partial response, 16 (43%) had stable invasive fungal disease, one (3%) had invasive fungal disease progression, three (8%) had missing assessments, and 13 (35%) had died. 35 patients (95%) had adverse events (28 [76%] serious). Day-42 crude all-cause mortality in seven (33%) of 21 primary-treatment isavuconazole cases was similar to 13 (39%) of 33 amphotericin B-treated matched controls (weighted all-cause mortality: 33% vs 41%; p=0·595). Isavuconazole showed activity against mucormycosis with efficacy similar to amphotericin B. Isavuconazole can be used for treatment of mucormycosis and is well tolerated. Astellas Pharma Global Development, Basilea Pharmaceutica International. Copyright © 2016 Elsevier Ltd. All rights reserved.

Obesity and Diabetes Mellitus Adversely Affect Outcomes after Cardiac Surgery in Children's Hospitals.

PubMed

Shamszad, Pirouz; Rossano, Joseph W; Marino, Bradley S; Lowry, Adam W; Knudson, Jarrod D

2016-09-01

To assess how obesity or diabetes mellitus impacts outcomes in patients undergoing cardiac surgery in pediatric hospitals. A multi-institutional, matched case-control study of the Pediatric Health Information System database was performed. Tertiary children's hospitals in the United States. All cardiac surgical cases in patients with obesity or diabetes mellitus between 2004 and 2012 were included. Cases were matched to controls by age, sex, race, and Risk Adjustment for Congenital Heart Surgery score. Mortality, surgical complications, and hospital utilization. Differences in outcome measures were assessed by chi-square and Mann-Whitney tests. P value < .05 was significant. Six hundred twenty-nine cardiac surgical cases (median age 17 years [IQR 12-32]) with obesity or diabetes mellitus were matched to 629 controls. Cases demonstrated lower median household income than those in the control group ($38,031 [IQR $31,900-$48,844] vs. ($41,896 [IQR $32,854-$56,020], P < .001). Mortality was similar between cases and controls (22% vs. 1.9%, P =.692). Surgical complications occurred similarly between cases and controls (13.5% vs. 12.4%, P = .535). Cases had longer intensive care unit length of stay than controls (3 vs. 2 days, P = .001), resulting in longer overall hospital length of stay (5 vs. 4 days, P < .001). Cases also had a higher odds of undergoing mechanical ventilation for >96 hours (OR 2.0, 95% CI 1.1-3.7) and higher rate of total parenteral nutrition use (7.2% vs. 4.5%, P = .040). Median hospital charges were higher in cases (clinical: $6,696 vs. $5,872; laboratory: $14,168 vs. $12,251; pharmacy: $12,971 vs. $10,426; imaging: $6,259 vs. $5,660; P ≤ .030 for all). The presence of obesity or diabetes mellitus was associated with increased postoperative morbidity, hospital utilization, and cost in patients undergoing cardiac surgery in pediatric hospitals. © 2016 Wiley Periodicals, Inc.

Risk factors associated with overdose among Bahraini youth.

PubMed

Al Ansari, A M; Hamadeh, R R; Matar, A M; Marhoon, H; Buzaboon, B Y; Raees, A G

2001-01-01

The aim of this study was to identify the risk factors of overdose among Bahraini youth (15-24 years). These factors included psychiatric disorders, family pathology, and psychosocial stress. All suicide attempters in the country during an 18-month period (N= 100) were identified prospectively. One hospital-matched control was selected for each case. Both cases and controls underwent a semistructured personal interview in the two state general hospitals. A matched pair analysis was done, as well as computation of McNemar's continuity corrected chi-square test, odds ratio, and the 95% confidence interval of the odds ratio. The overdose attempter was more likely than the control to be unemployed, a member of a non-intact family, having a mother whose education was high school or above, not having a friend, involved in a boy/girlfriend relationship, and a cigarette smoker. More students among attempters had failed an examination in the past year than matched controls. Father's education, social class, death of father, recent row with a friend, use of drugs and alcohol, relationship with teachers, recent mobility, financial difficulties, and legal problems were similar in both groups. Stresses generated from living in a non-intact family, interpersonal relationships mainly with the opposite sex, unemployment, and school performance came out as the main risk factors. The association of previously identified risk factors such as depression, aggressive behavior, and use of drug and alcohol was low among attempters. While the results of this study are consistent with the present view that suicidal behaviors are multifactorial in origin, the magnitude and effect of each factor are culturally determined.

Neonatal vitamin D status and risk of schizophrenia: a population-based case-control study.

PubMed

McGrath, John J; Eyles, Darryl W; Pedersen, Carsten B; Anderson, Cameron; Ko, Pauline; Burne, Thomas H; Norgaard-Pedersen, Bent; Hougaard, David M; Mortensen, Preben B

2010-09-01

Clues from the epidemiology of schizophrenia suggest that low levels of developmental vitamin D may be associated with increased risk of schizophrenia. To directly examine the association between neonatal vitamin D status and risk of schizophrenia. Individually matched case-control study drawn from a population-based cohort. Danish national health registers and neonatal biobank. A total of 424 individuals with schizophrenia and 424 controls matched for sex and date of birth. The concentration of 25 hydroxyvitamin D(3) (25[OH]D3) was assessed from neonatal dried blood samples using a highly sensitive liquid chromatography tandem mass spectroscopy method. Relative risks were calculated for the matched pairs when examined for quintiles of 25(OH)D3. Compared with neonates in the fourth quintile (with 25[OH]D3 concentrations between 40.5 and 50.9 nmol/L), those in each of the lower 3 quintiles had a significantly increased risk of schizophrenia (2-fold elevated risk). Unexpectedly, those in the highest quintile also had a significantly increased risk of schizophrenia. Based on this analysis, the population-attributable fraction associated with neonatal vitamin D status was 44%. The relationship was not explained by a wide range of potential confounding or interacting variables. Both low and high concentrations of neonatal vitamin D are associated with increased risk of schizophrenia, and it is feasible that this exposure could contribute to a sizeable proportion of cases in Denmark. In light of the substantial public health implications of this finding, there is an urgent need to further explore the effect of vitamin D status on brain development and later mental health.

Statistical methods for analysis of radiation effects with tumor and dose location-specific information with application to the WECARE study of asynchronous contralateral breast cancer

PubMed Central

Langholz, Bryan; Thomas, Duncan C.; Stovall, Marilyn; Smith, Susan A.; Boice, John D.; Shore, Roy E.; Bernstein, Leslie; Lynch, Charles F.; Zhang, Xinbo; Bernstein, Jonine L.

2009-01-01

Summary Methods for the analysis of individually matched case-control studies with location-specific radiation dose and tumor location information are described. These include likelihood methods for analyses that just use cases with precise location of tumor information and methods that also include cases with imprecise tumor location information. The theory establishes that each of these likelihood based methods estimates the same radiation rate ratio parameters, within the context of the appropriate model for location and subject level covariate effects. The underlying assumptions are characterized and the potential strengths and limitations of each method are described. The methods are illustrated and compared using the WECARE study of radiation and asynchronous contralateral breast cancer. PMID:18647297

Maternal characteristics and birth outcomes of pregnant women who had offspring with congenital ear abnormalities - a population-based case-control study.

PubMed

Paput, László; Bánhidy, Ferenc; Czeizel, Andrew E

2011-09-01

To describe the maternal characteristics and birth outcomes of newborn infants affected with isolated ear congenital abnormalities (IECA), mainly isolated anotia/microtia and unclassified multiple congenital abnormalities (CAs) including anotia/microtia (UMAM). Cases with IECA and UMAM were compared with their matched controls and all controls without any defect and malformed controls affected with other defects in the population-based large dataset of the Hungarian Case-Control Surveillance of Congenital Abnormalities. The mothers of 354 cases with IECA did not show significant difference in age, but their mean birth order was higher while their socio-economic status based on the maternal employment status was lower compared to the figures of their matched controls. There was a male excess among cases with microtia and mainly with UMAM. The evaluation of birth outcomes of newborns affected with IECA indicated intrauterine fetal growth retardation. Newborn infants with isolated microtia had intrauterine growth retardation and the association of this developmental defect localized for a small region of head with the general fetal development raises interesting theoretical question.

The Association Between Mild Intraoperative Hypotension and Stroke in General Surgery Patients.

PubMed

Hsieh, Jason K; Dalton, Jarrod E; Yang, Dongsheng; Farag, Ehab S; Sessler, Daniel I; Kurz, Andrea M

2016-10-01

Intraoperative hypotension may contribute to perioperative strokes. We therefore tested the hypothesis that intraoperative hypotension is associated with perioperative stroke. After institutional review board approval for this case-control study, we identified patients who had nonneurological, noncardiac, and noncarotid surgery under general anesthesia at the Cleveland Clinic between 2005 and 2011 and experienced a postoperative stroke. Control patients not experiencing postoperative stroke were matched in a 4-to-1 ratio using propensity scores and restriction to the same procedure type as stroke patients. The association between intraoperative hypotension, measured as time-integrated area under a mean arterial pressure (MAP) of 70 mm Hg, and postoperative stroke was assessed using zero-inflated negative binomial regression. Among 106 337 patients meeting inclusion criteria, we identified 120 who had confirmed postoperative stroke events based on manual chart review. Four-to-one propensity matching yielded a final matched sample of 104 stroke cases and 398 controls. There was no association between stroke and intraoperative hypotension. Stroke patients were not more likely than controls to have been hypotensive (odds ratio, 0.49 [0.18-1.38]), and among patients with intraoperative hypotension, stroke patients did not experience a greater degree of hypotension than controls (ratio of geometric means, 1.07 [0.76-1.53]). In our propensity score-matched case-control study, we did not find an association between intraoperative hypotension, defined as MAP < 70 mm Hg, and postoperative stroke.

The Role of Procurement Biopsies in Acceptance Decisions for Kidneys Retrieved for Transplant

PubMed Central

Stewart, Darren E.; Bista, Bipin R.; Salkowski, Nicholas; Snyder, Jon J.; Israni, Ajay K.; Crary, Gretchen S.; Rosendale, John D.; Matas, Arthur J.; Delmonico, Francis L.

2014-01-01

Background and objectives There is a shortage of kidneys for transplant, and many patients on the deceased donor kidney transplant waiting list would likely benefit from kidneys that are currently being discarded. In the United States, the most common reason given for discarding kidneys retrieved for transplant is procurement biopsy results. This study aimed to compare biopsy results from discarded kidneys with discard attributed to biopsy findings, with biopsy results from comparable kidneys that were successfully transplanted. Design, setting, participants, & measurements In this retrospective, observational, case-control study, biopsy reports were examined from 83 kidneys discarded in 2010 due to biopsy findings (cases), 83 contralateral transplanted kidneys from the same donor (contralateral controls), and 83 deceased donors randomly matched to cases by donor risk profile (randomly matched controls). A second procurement biopsy was obtained in 64 of 332 kidneys (19.3%). Results The quality of biopsy reports was low, with amounts of tubular atrophy, interstitial inflammation, arteriolar hyalinosis, and acute tubular necrosis often not indicated; 69% were wedge biopsies and 94% used frozen tissue. The correlation between first and second procurement biopsies was poor; only 25% of the variability (R2) in glomerulosclerosis was explained by biopsies being from the same kidney. The percentages of glomerulosclerosis overlapped substantially between cases, contralateral controls, and randomly matched controls: 17.1%±15.3%, 9.0%±6.6%, and 5.0%±5.9%, respectively. Of all biopsy findings, only glomerulosclerosis>20% was independently correlated with discard (cases versus contralateral controls; odds ratio, 15.09; 95% confidence interval, 2.47 to 92.41; P=0.003), suggesting that only this biopsy result was used in acceptance decisions. One-year graft survival was 79.5% and 90.7% in contralateral and randomly matched controls, respectively, versus 91.6% among all deceased donor transplants in the Scientific Registry of Transplant Recipients. Conclusions Routine use of biopsies could lead to unnecessary kidney discards. PMID:24558053

Factors associated with adult poisoning in northern Malaysia: a case-control study.

PubMed

Fathelrahman, A I; Ab Rahman, A F; Zain, Z Mohd; Tengku, M A

2006-04-01

Data on adult risk factors associated with drug or chemical poisonings in Malaysia are scarce. The objective of the study was to identify possible risk factors associated with adult admissions to the Penang General Hospital (PGH) due to chemical poisoning and/or drug overdose. The present study was a case-control study, conducted over 18 weeks. One hundred acutely poisoned adult patients admitted to PGH during the period from September 2003 to February 2004 were considered as cases. Two hundred patients admitted to the same medical wards for other illnesses, during the same period, were matched for age and gender with the poisoned cases and thus selected as controls. McNemar test and binary logistic were used for univariate analysis and logistic regression analysis for multivariate analyses. The odds ratio (OR) and its 95% confidence interval (95% CI) were calculated for each predictor variable. Positive histories of psychiatric illness and previous poisoning, problems in boy/girl friend relationships, family problems, marital problems, Indian ethnicity, Chinese ethnicity, living in rented houses and living in a household with less than five people were significant risk factors associated with adult admissions due to poisoning.

Statin Medications and the Risk of Gynecomastia.

PubMed

Skeldon, Sean C; Carleton, Bruce; Brophy, James; Sodhi, Mohit; Etminan, Mahyar

2018-06-19

Case reports have suggested an increased risk of gynecomastia with HMG-CoA reductase inhibitors (i.e. statins). A recent meta-analysis also found that statins decrease circulating testosterone levels in men. We investigated whether statin use was associated with an increased risk of gynecomastia. Case control study. A cohort of patients from a random sample of 9,053,240 US subjects from the PharMetrics Plus ™ health claims database from 2006 to 2016 was created. New cases of gynecomastia requiring at least two ICD-9 codes were identified from the cohort and matched to 10 controls by follow-up time and age using density-based sampling. Rate ratios (RRs) for past users of statins were computed using conditional logistic regression adjusting for alcoholic cirrhosis, hyperthyroidism, testicular cancer, Klinefelter syndrome, obesity, hypogonadism, hyperprolactinemia and use of spironolactone, ketoconazole, H 2 receptor antagonists (H 2 blockers), risperidone, testosterone and androgen deprivation therapy. Our cohort included 6,147 cases of gynecomastia and 61,470 corresponding matched controls. The adjusted RR for current, recent and past statin use with respect to gynecomastia was 1.19 (1.04-1.36), 1.38 (1.15-1.65) and 1.20 (1.03-1.40) respectively. Statin use is associated with an increased risk of developing gynecomastia. Clinicians should be cognizant of this effect and educate patients accordingly. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Effectiveness of pneumococcal vaccination for elderly people in Catalonia, Spain: a case-control study.

PubMed

Dominguez, Angela; Salleras, Lluis; Fedson, David S; Izquierdo, Conchita; Ruiz, Laura; Ciruela, Pilar; Fenoll, Asuncion; Casal, Julio

2005-05-01

Observational studies offer an approach to evaluating the effectiveness of vaccination programs. We evaluated the effectiveness of a 23-valent pneumococcal vaccination program for elderly people in Catalonia, Spain, in a matched-set case-control study. We identified 149 cases of invasive pneumococcal disease among patients aged > or =65 years who were hospitalized in 12 large hospitals in Catalonia during the period of 1 January 2001 through 31 March 2002. We selected 2 hospital control patients and 1 outpatient control subject for each case patient, matching on the basis of age and underlying medical conditions. We obtained their pneumococcal vaccination histories and used conditional logistic regression to determine effectiveness of vaccination. Among all 149 cases of invasive pneumococcal disease, 131 (87.9%) were caused by vaccine or vaccine-related serotypes. In the adjusted analysis, overall effectiveness of vaccination against infections due to all serotypes was 70% (95% confidence interval [CI], 48%-82%). Among immunocompetent subjects with or without high-risk conditions, effectiveness of vaccination was 76% (95% CI, 51%-88%), but among immunocompromised subjects it was 50% (95% CI, -44% to 82%). Among subjects with infections due to vaccine or vaccine-related serotypes, effectiveness of vaccination was 72% (95% CI, 50%-85%) overall and 78% (95% CI, 50%-90%) in those who were immunocompetent, but it was only 46% (95% CI, -54% to 81%) in those who were immunocompromised. Overall effectiveness of vaccination was 65% (95% CI, 35%-81%) during the noninfluenza period. Pneumococcal vaccination was effective in preventing invasive pneumococcal disease among all elderly persons in Catalonia. Effectiveness was greater in immunocompetent persons, most of whom had underlying high-risk conditions. The number of subjects was too small to determine whether vaccination was effective in those who were immunocompromised.

Drug interactions with phenprocoumon and the risk of serious haemorrhage: a nested case-control study in a large population-based German database.

PubMed

Jobski, Kathrin; Behr, Sigrid; Garbe, Edeltraut

2011-09-01

Phenprocoumon is the most frequently used vitamin K antagonist in Germany. The aim of this study was to estimate the risk of serious bleeding as a result of the use of drugs with potential interaction with phenprocoumon. We conducted a nested case-control study in a cohort of 246,220 phenprocoumon users in the German Pharmacoepidemiological Research Database. Cases were patients hospitalised for haemorrhage of different kinds. Ten controls were matched to each case by health insurance, birth year and sex using incidence density sampling. Odds ratios (OR) with 95% confidence intervals (CI) of the risk of serious bleeding associated with combined use of phenprocoumon and potentially interacting drugs versus phenprocoumon alone were estimated using conditional logistic regression analysis. Our analyses considered multiple risk factors, such as bleeding history, other comorbidities or co-medication. Our study included 2,553 cases and 25,348 matched controls. An increased risk of bleeding was observed for the combined use of phenprocoumon and clopidogrel vs phenprocoumon use alone (OR: 1.83, 95% CI: 1.41-2.36). Antibiotic drugs associated with an increased risk of haemorrhage in the population of phenprocoumon users included the group of quinolones with ORs ranging from 2.74 (95% CI: 1.80-4.18) for ciprofloxacin to 4.40 (95% CI: 2.45-7.89) for levofloxacin, amoxicillin plus clavulanic acid (OR: 2.99, 95% CI: 1.39-6.42) and cotrimoxazole (OR 3.57, 95% CI: 2.36-5.40). Among non-steroidal anti-inflammatory drugs (NSAIDs), ketoprofen and naproxen were associated with the highest risks. Significantly elevated risks of major bleeding were mainly observed for drugs with known pharmacodynamic interaction with phenprocoumon, and less for drugs with possible pharmacokinetic interaction.

Vaccine Effectiveness against Influenza in 2015/16 in Hospital and Ambulatory Medical Care Facilities: Polish Results of the European I-MOVE+ Multicenter Study.

PubMed

Paradowska-Stankiewicz, Iwona; Korczyńska, Monika R; Cieślak, Katarzyna; Kowalczyk, Dorota; Szymański, Karol; Brydak, Lidia B

2018-01-01

Influenza vaccination is the best measure available to prevent seasonal influenza infection. The majority of studies on vaccine effectiveness in the 2015/16 season conducted in the European I-MOVE+ Project, show that a match between the circulating influenza strains in the general public and those included in the vaccine for the Northern Hemisphere was low to moderate. As part of I-MOVE+, Poland has implemented a case control negative study design and molecular biology methods, such as real time RT-PCR, to assess the vaccine match and effectiveness. The research described herein consisted of two major influenza vaccine effectiveness investigations conducted in Poland in the 2015/16 season. The general practice part of the study included 228 cases consisting of 159 type A, 65 type B, and 4 coinfections (types A + B), and 312 negative control cases. The hospital study part included 26 cases consisting of 21 type A, 2 type B, and 3 coinfections, and 13 negative control cases. The data were collected from patients of all ages recruited by 46 volunteering doctors in 15 Poland's provinces and three hospitals, respectively. In both study parts, only were seven patients and 12 control subjects vaccinated. Low vaccine coverage, a major limitation of the Polish study, makes the calculation of vaccine effectiveness for the Polish population hardly applicable statistically. Despite the crudeness of data, they were included into the common European analysis. The overall vaccine effectiveness amounted to 21.0% (95% CI: 74-122). It was somehow better for type B virus: 53.9% (95% CI: 47-87) and type A virus: 23.6% (95% CI: 83-185). A larger sample size is needed to achieve a desired interpretation of results on influenza vaccine effectiveness in Poland.

Effectiveness of vaccination with 23-valent pneumococcal polysaccharide vaccine in preventing hospitalization with laboratory confirmed influenza during the 2009-2010 and 2010-2011 seasons

PubMed Central

Domínguez, Angela; Castilla, Jesús; Godoy, Pere; Delgado-Rodríguez, Miguel; Saez, Marc; Soldevila, Núria; Astray, Jenaro; Mayoral, José María; Martín, Vicente; Quintana, José María; González-Candelas, Fernando; Galán, Juan Carlos; Tamames, Sonia; Castro, Ady; Baricot, Maretva; Garín, Olatz; Pumarola, Tomas; Working Group (Spain), CIBERESP Cases and Controls in Pandemic Influenza

2013-01-01

Background: Since influenza predisposes to bacterial pneumonia caused by Streptococcus pneumoniae, studies have suggested that pneumococcal vaccination might reduce its occurrence during pandemics. We assessed the effectiveness of pneumococcal polysaccharide vaccination alone and in combination with influenza vaccination in preventing influenza hospitalization during the 2009–2010 pandemic wave and 2010–2011 influenza epidemic. Methods: We conducted a multicenter case-control study in 36 Spanish hospitals. We selected patients aged ≥ 18 y hospitalized with confirmed influenza and two hospitalized controls per case, matched according to age, date of hospitalization and province of residence. Multivariate analysis was performed using conditional logistic regression. Subjects were considered vaccinated if they had received the pneumococcal or seasonal influenza vaccine > 14 d (or > 7 d for pandemic influenza vaccine) before the onset of symptoms (cases) or the onset of symptoms in matched cases (controls). Results: 1187 cases and 2328 controls were included. The adjusted estimate of effectiveness of pneumococcal vaccination in preventing influenza hospitalization was 41% (95% CI 8–62) in all patients and 43% (95% CI 2–78) in patients aged ≥ 65 y. The adjusted effectiveness of dual PPV23 and influenza vaccination was 81% (95% CI 65–90) in all patients and 76% (95% CI 46–90) in patients aged ≥ 65 y. The adjusted effectiveness of influenza vaccination alone was 58% (95% CI 38–72). Conclusions: In elderly people and adults with chronic illness, pneumococcal vaccination may reduce hospitalizations during the influenza season. In people vaccinated with both the influenza and pneumococcal vaccines, the benefit in hospitalizations avoided was greater than in those vaccinated only against influenza. PMID:23563516

Nonsteroidal Anti-Inflammatory Drug without Antibiotics for Acute Viral Infection Increases the Empyema Risk in Children: A Matched Case-Control Study.

PubMed

Le Bourgeois, Muriel; Ferroni, Agnès; Leruez-Ville, Marianne; Varon, Emmanuelle; Thumerelle, Caroline; Brémont, François; Fayon, Michael J; Delacourt, Christophe; Ligier, Caroline; Watier, Laurence; Guillemot, Didier

2016-08-01

To investigate the risk factors of empyema after acute viral infection and to clarify the hypothesized association(s) between empyema and some viruses and/or the use of nonsteroidal anti-inflammatory drugs (NSAIDs). A case-control study was conducted in 15 centers. Cases and controls were enrolled for a source population of children 3-15 years of age with acute viral infections between 2006 and 2009. Among 215 empyemas, 83 cases (children with empyema and acute viral infection within the 15 preceding days) were included, and 83 controls (children with acute viral infection) were matched to cases. Considering the intake of any drug within 72 hours after acute viral infection onset and at least 6 consecutive days of antibiotic use and at least 1 day of NSAIDs exposure, the multivariable analysis retained an increased risk of empyema associated with NSAIDs exposure (aOR 2.79, 95% CI 1.4-5.58, P = .004), and a decreased risk associated with antibiotic use (aOR 0.32, 95% CI 0.11-0.97, P = .04). The risk of empyema associated with NSAIDs exposure was greater for children not prescribed an antibiotic and antibiotic intake diminished that risk for children given NSAIDs. NSAIDs use during acute viral infection is associated with an increased risk of empyema in children, and antibiotics are associated with a decreased risk. The presence of antibiotic-NSAIDs interaction with this risk is suggested. These findings suggest that NSAIDs should not be recommended as a first-line antipyretic treatment during acute viral infections in children. Copyright © 2016 Elsevier Inc. All rights reserved.

Case-control study on risk factors for acute hepatitis E in Germany, 2012 to 2014.

PubMed

Faber, Mirko; Askar, Mona; Stark, Klaus

2018-05-01

BackgroundNotified cases of hepatitis E have increased 40-fold in the past 10 years in Germany. Food safety is a major concern as hepatitis E virus (HEV) RNA has been detected in ready-to-eat retail-level food products. The objective of this case-control study was to assess risk factors for autochthonous symptomatic hepatitis E and explore reasons for delays in diagnosis. Methods: Demographic, clinical and exposure data from notified hepatitis E cases and individually matched population controls were collected in semi-standardised telephone interviews. Conditional logistic regression analysis was used to calculate matched odds ratios (mOR) and population attributable fractions (PAF). Results: In total, 270 cases and 1,159 controls were included (mean age 53 years, 61% men in both groups). Associated with disease were: consumption of undercooked pork liver, pork, wild boar meat, frankfurters, liver sausage and raw vegetables; contact with waste water (occupational) and various host factors (mORs between 1.9 and 34.1, p value < 0.03). PAF for frankfurters and liver sausage were 17.6%, and 23.6%, respectively. There were statistically significant differences in the clinical presentation and hospitalisation proportion of acute hepatitis E in men and women. Diagnosis was preceded by more invasive procedures in 29.2% of patients, suggesting that hepatitis E was not immediately considered as a common differential diagnosis. Conclusions: Our study suggests that there are indeed sex-specific differences in disease development and lends important epidemiological evidence to specific ready-to-eat pork products as a major source for autochthonous hepatitis E. A review of existing consumer recommendations and production methods may be indicated.

Health-related quality of life among long-term rectal cancer survivors with an ostomy: manifestations by sex.

PubMed

Krouse, Robert S; Herrinton, Lisa J; Grant, Marcia; Wendel, Christopher S; Green, Sylvan B; Mohler, M Jane; Baldwin, Carol M; McMullen, Carmit K; Rawl, Susan M; Matayoshi, Eric; Coons, Stephen Joel; Hornbrook, Mark C

2009-10-01

Intestinal stomas can pose significant challenges for long-term (> or = 5 years) rectal cancer (RC) survivors. Specifying common challenges and sociodemographic or clinical differences will further the development of tailored interventions to improve health-related quality of life (HRQOL). This was a matched cross-sectional study of long-term RC survivors conducted in three Kaiser Permanente regions. The mailed questionnaire included the modified City of Hope Quality of Life-Ostomy (mCOH-QOL-Ostomy) and Medical Outcomes Study 36-Item Short-Form Health Survey, version 2 (SF-36v2). Groups surveyed were permanent ostomates (cases) and those who did not require an ostomy (controls). RC survivors were matched on sex, age, and time since diagnosis. Comparisons between groups used regression analysis with adjustment for age, comorbidity score, history of radiation therapy, income, and work status. Response rate was 54% (491 of 909). Cases and controls had similar demographic characteristics. On the basis of the mCOH-QOL-Ostomy, both male and female cases had significantly worse social well-being compared with controls, while only female cases reported significantly worse overall HRQOL and psychological well-being. For younger females (< age 75 years), ostomy had a greater impact on physical well-being compared with older females. Based on the SF-36v2, statistically significant and meaningful differences between female cases and controls were observed for seven of the eight scales and on the physical and mental component summary scores. Men and women report a different profile of challenges, suggesting the need for targeted or sex-specific interventions to improve HRQOL in this population. This may include focus on physical HRQOL for female ostomy survivors younger than age 75.

Health-Related Quality of Life Among Long-Term Rectal Cancer Survivors With an Ostomy: Manifestations by Sex

PubMed Central

Krouse, Robert S.; Herrinton, Lisa J.; Grant, Marcia; Wendel, Christopher S.; Green, Sylvan B.; Mohler, M. Jane; Baldwin, Carol M.; McMullen, Carmit K.; Rawl, Susan M.; Matayoshi, Eric; Coons, Stephen Joel; Hornbrook, Mark C.

2009-01-01

Purpose Intestinal stomas can pose significant challenges for long-term (≥ 5 years) rectal cancer (RC) survivors. Specifying common challenges and sociodemographic or clinical differences will further the development of tailored interventions to improve health-related quality of life (HRQOL). Patients and Methods This was a matched cross-sectional study of long-term RC survivors conducted in three Kaiser Permanente regions. The mailed questionnaire included the modified City of Hope Quality of Life-Ostomy (mCOH-QOL-Ostomy) and Medical Outcomes Study 36-Item Short-Form Health Survey, version 2 (SF-36v2). Groups surveyed were permanent ostomates (cases) and those who did not require an ostomy (controls). RC survivors were matched on sex, age, and time since diagnosis. Comparisons between groups used regression analysis with adjustment for age, comorbidity score, history of radiation therapy, income, and work status. Results Response rate was 54% (491 of 909). Cases and controls had similar demographic characteristics. On the basis of the mCOH-QOL-Ostomy, both male and female cases had significantly worse social well-being compared with controls, while only female cases reported significantly worse overall HRQOL and psychological well-being. For younger females (< age 75 years), ostomy had a greater impact on physical well-being compared with older females. Based on the SF-36v2, statistically significant and meaningful differences between female cases and controls were observed for seven of the eight scales and on the physical and mental component summary scores. Conclusion Men and women report a different profile of challenges, suggesting the need for targeted or sex-specific interventions to improve HRQOL in this population. This may include focus on physical HRQOL for female ostomy survivors younger than age 75. PMID:19720920

Cell-free fetal DNA concentration in plasma of patients with abnormal uterine artery Doppler waveform and intrauterine growth restriction--a pilot study.

PubMed

Caramelli, Elisabetta; Rizzo, Nicola; Concu, Manuela; Simonazzi, Giuliana; Carinci, Paolo; Bondavalli, Corrado; Bovicelli, Luciano; Farina, Antonio

2003-05-01

To evaluate if an increased amount of fetal DNA concentration can be found in women screened positive for intrauterine growth restriction because of abnormal uterine artery Doppler waveforms. We enrolled eight pregnant women (each bearing a male fetus), with the evidence of abnormal uterine artery Doppler waveforms, and 16 control patients for a case-control study matched for gestational age (1 : 2). Uterine artery Doppler was carried out at 20 to 35 weeks' gestation (median 29). The mean uterine artery resistance index (RI) was subsequently calculated, and a value >0.6 was considered positive for the clinical features of pre-eclampsia. The SRY locus was used to determine the amount of male fetal DNA in the maternal plasma at the time of Doppler analysis. Two controls (normal Doppler) were excluded from the final analysis because they had a pre-term delivery. One case (abnormal Doppler) had evidence of intrauterine growth restriction at the time of enrolment. In four out of eight cases (abnormal Doppler), intrauterine growth restriction was subsequently observed. Multiples of median (MoM) conversion of the fetal DNA values showed an increase of 1.81 times in the cases when compared to the controls. An increase of 2.16 times was instead observed for the cases with a growth-restricted fetus (5 cases out of 8) in comparison with the controls (14 cases). In subjects positive to uterine artery Doppler velocimetry analysis (Doppler analysis for pre-eclampsia screening), the fetal DNA concentration is higher than expected, in the absence of any other clinical feature. Since the increase in fetal DNA seems to be related to the presence or to the future development of intrauterine growth restriction, this paper suggests a possible integration between ultrasound and molecular markers for predicting the disease in some cases. Copyright 2003 John Wiley & Sons, Ltd.

Analysis of User Interaction with a Brain-Computer Interface Based on Steady-State Visually Evoked Potentials: Case Study of a Game

PubMed Central

de Carvalho, Sarah Negreiros; Costa, Thiago Bulhões da Silva; Attux, Romis; Hornung, Heiko Horst; Arantes, Dalton Soares

2018-01-01

This paper presents a systematic analysis of a game controlled by a Brain-Computer Interface (BCI) based on Steady-State Visually Evoked Potentials (SSVEP). The objective is to understand BCI systems from the Human-Computer Interface (HCI) point of view, by observing how the users interact with the game and evaluating how the interface elements influence the system performance. The interactions of 30 volunteers with our computer game, named “Get Coins,” through a BCI based on SSVEP, have generated a database of brain signals and the corresponding responses to a questionnaire about various perceptual parameters, such as visual stimulation, acoustic feedback, background music, visual contrast, and visual fatigue. Each one of the volunteers played one match using the keyboard and four matches using the BCI, for comparison. In all matches using the BCI, the volunteers achieved the goals of the game. Eight of them achieved a perfect score in at least one of the four matches, showing the feasibility of the direct communication between the brain and the computer. Despite this successful experiment, adaptations and improvements should be implemented to make this innovative technology accessible to the end user. PMID:29849549

Analysis of User Interaction with a Brain-Computer Interface Based on Steady-State Visually Evoked Potentials: Case Study of a Game.

PubMed

Leite, Harlei Miguel de Arruda; de Carvalho, Sarah Negreiros; Costa, Thiago Bulhões da Silva; Attux, Romis; Hornung, Heiko Horst; Arantes, Dalton Soares

2018-01-01

This paper presents a systematic analysis of a game controlled by a Brain-Computer Interface (BCI) based on Steady-State Visually Evoked Potentials (SSVEP). The objective is to understand BCI systems from the Human-Computer Interface (HCI) point of view, by observing how the users interact with the game and evaluating how the interface elements influence the system performance. The interactions of 30 volunteers with our computer game, named "Get Coins," through a BCI based on SSVEP, have generated a database of brain signals and the corresponding responses to a questionnaire about various perceptual parameters, such as visual stimulation, acoustic feedback, background music, visual contrast, and visual fatigue. Each one of the volunteers played one match using the keyboard and four matches using the BCI, for comparison. In all matches using the BCI, the volunteers achieved the goals of the game. Eight of them achieved a perfect score in at least one of the four matches, showing the feasibility of the direct communication between the brain and the computer. Despite this successful experiment, adaptations and improvements should be implemented to make this innovative technology accessible to the end user.

History of preeclampsia is more predictive of cardiometabolic and cardiovascular risk factors than obesity.

PubMed

Heidema, Wieteke M; Scholten, Ralph R; Lotgering, Fred K; Spaanderman, Marc E A

2015-11-01

To determine to what extent a history of preeclampsia affects traditional cardiometabolic (insulin resistance and dyslipidemia) and cardiovascular (hypertension and micro-albuminuria) risk factors of the metabolic syndrome irrespective of BMI. In a retrospective case-control study we compared 90 formerly preeclamptic women, divided in 3 BMI-classes (BMI 19.5-24.9, 25.0-29.9, ≥30.0kg/m(2)) to 30 controls, matched for BMI, age and parity. Cardiometabolic and cardiovascular risk factors (WHO-criteria) were tested 6-18 months post partum. Statistical analysis included unpaired t-tests, Mann-Whitney U test, or Chi square test and two-way ANOVA. Constituents of the metabolic syndrome (glucose, insulin, HOMAIR, HDL-cholesterol, triglycerides, blood pressure, micro-albuminuria) were higher in formerly preeclamptic women than in BMI-matched controls. Resultantly, traditional risk factors were more prevalent in formerly preeclamptic women than in controls (insulin resistance 80% vs 30%, dyslipidemia 52% vs 3%, hypertension 24% vs 0%, micro-albuminuria 30% vs 0%). Cardiometabolic risk factors increased with BMI, to the same extent in both groups. Formerly preeclamptic women had metabolic syndrome more often than their BMI-matched controls (38% vs 3%, p<0.001). Traditional risk factors of the metabolic syndrome are more prevalent in formerly preeclamptic women than in BMI-matched controls and increase with BMI to the same extent in both groups. A history of preeclampsia seems to be a stronger indicator of cardiovascular risk than obesity per se. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Increased risk of narcolepsy in children and adults after pandemic H1N1 vaccination in France.

PubMed

Dauvilliers, Yves; Arnulf, Isabelle; Lecendreux, Michel; Monaca Charley, Christelle; Franco, Patricia; Drouot, Xavier; d'Ortho, Marie-Pia; Launois, Sandrine; Lignot, Séverine; Bourgin, Patrice; Nogues, Béatrice; Rey, Marc; Bayard, Sophie; Scholz, Sabine; Lavault, Sophie; Tubert-Bitter, Pascale; Saussier, Cristel; Pariente, Antoine

2013-08-01

An increased incidence of narcolepsy in children was detected in Scandinavian countries where pandemic H1N1 influenza ASO3-adjuvanted vaccine was used. A campaign of vaccination against pandemic H1N1 influenza was implemented in France using both ASO3-adjuvanted and non-adjuvanted vaccines. As part of a study considering all-type narcolepsy, we investigated the association between H1N1 vaccination and narcolepsy with cataplexy in children and adults compared with matched controls; and compared the phenotype of narcolepsy with cataplexy according to exposure to the H1N1 vaccination. Patients with narcolepsy-cataplexy were included from 14 expert centres in France. Date of diagnosis constituted the index date. Validation of cases was performed by independent experts using the Brighton collaboration criteria. Up to four controls were individually matched to cases according to age, gender and geographic location. A structured telephone interview was performed to collect information on medical history, past infections and vaccinations. Eighty-five cases with narcolepsy-cataplexy were included; 23 being further excluded regarding eligibility criteria. Of the 62 eligible cases, 59 (64% males, 57.6% children) could be matched with 135 control subjects. H1N1 vaccination was associated with narcolepsy-cataplexy with an odds ratio of 6.5 (2.1-19.9) in subjects aged<18 years, and 4.7 (1.6-13.9) in those aged 18 and over. Sensitivity analyses considering date of referral for diagnosis or the date of onset of symptoms as the index date gave similar results, as did analyses focusing only on exposure to ASO3-adjuvanted vaccine. Slight differences were found when comparing cases with narcolepsy-cataplexy exposed to H1N1 vaccination (n=32; mostly AS03-adjuvanted vaccine, n=28) to non-exposed cases (n=30), including shorter delay of diagnosis and a higher number of sleep onset rapid eye movement periods for exposed cases. No difference was found regarding history of infections. In this sub-analysis, H1N1 vaccination was strongly associated with an increased risk of narcolepsy-cataplexy in both children and adults in France. Even if, as in every observational study, the possibility that some biases participated in the association cannot be completely ruled out, the associations appeared robust to sensitivity analyses, and a specific analysis focusing on ASO3-adjuvanted vaccine found similar increase.

Associated factors and outcomes for OXA-232 Carbapenem-resistant Enterobacteriaceae infections in a tertiary care centre in Mexico City: A case-control-control study.

PubMed

Torres-González, Pedro; Ortiz-Brizuela, Edgar; Cervera-Hernandez, Miguel Enrique; Bobadilla-Del Valle, Miriam; Martínez-Gamboa, Areli; Sifuentes-Osornio, José; Ponce-de-Leon, Alfredo

2016-10-01

We describe the outcomes and factors associated with OXA-232 producing carbapenem-resistant Enterobacteriaceae infections. A case-control-control study was performed; each case of infection by a carbapenem-resistant/OXA-232 (OXA-232-cases, n=27) was matched by isolation site, species, and date, with 2 cases of infection by carbapenem-susceptible/third-generation cephalosporin-susceptible (TGCS-controls, n=54) and 2 cases by carbapenem-susceptible/ESBL producing Enterobacteriaceae (ESBL-controls, n=54); 66% were urinary tract and 18.5% intra-abdominal infections. In the multivariable analysis with ESBL-controls, previous use β-lactam/β-lactamase antibiotics (OR 6.2; 95% CI 1.6-23.8) and, third-generation cephalosporins (OR 0.2; 95% CI 0.05-0.8) were associated with OXA-232 infection; with TGSC-controls previous use of β-lactam/β-lactamase antibiotics (OR 3.7; 95% 1.1-12.0) was associated. Among the OXA-232-cases, 29% received imipenem/cilastatin or meropenem, 11.1% ceftriaxone, 22.2% a carbapenem-based combination and 33.3% other antimicrobials as treatment. Previous β-lactam/β-lactamase antibiotics are associated with OXA-232 infections, and some may be treated with other active carbapenems or, in the absence of ESBL, third-generation cephalosporins. Copyright © 2016 Elsevier Inc. All rights reserved.

Outbreak of haemolytic uraemic syndrome in Norway caused by stx2-positive Escherichia coli O103:H25 traced to cured mutton sausages

PubMed Central

Schimmer, Barbara; Nygard, Karin; Eriksen, Hanne-Merete; Lassen, Jørgen; Lindstedt, Bjørn-Arne; Brandal, Lin T; Kapperud, Georg; Aavitsland, Preben

2008-01-01

Background On 20–21 February 2006, six cases of diarrhoea-associated haemolytic uraemic syndrome (HUS) were reported by paediatricians to the Norwegian Institute of Public Health. We initiated an investigation to identify the etiologic agent and determine the source of the outbreak in order to implement control measures. Methods A case was defined as a child with diarrhoea-associated HUS or any person with an infection with the outbreak strain of E. coli O103 (defined by the multi-locus variable number tandem repeats analysis (MLVA) profile) both with illness onset after January 1st 2006 in Norway. After initial hypotheses-generating interviews, we performed a case-control study with the first fifteen cases and three controls for each case matched by age, sex and municipality. Suspected food items were sampled, and any E. coli O103 strains were typed by MLVA. Results Between 20 February and 6 April 2006, 17 cases were identified, of which 10 children developed HUS, including one fatal case. After pilot interviews, a matched case-control study was performed indicating an association between a traditional cured sausage (odds ratio 19.4 (95% CI: 2.4–156)) and STEC infection. E. coli O103:H25 identical to the outbreak strain defined by MLVA profile was found in the product and traced back to contaminated mutton. Conclusion We report an outbreak caused by a rare STEC variant (O103:H25, stx2-positive). More than half of the diagnosed patients developed HUS, indicating that the causative organism is particularly virulent. Small ruminants continue to be important reservoirs for human-pathogen STEC. Improved slaughtering hygiene and good manufacturing practices for cured sausage products are needed to minimise the possibility of STEC surviving through the entire sausage production process. PMID:18387178

Clinical and psychological features of normal-weight women with subthreshold anorexia nervosa: a pilot case-control observational study.

PubMed

Tagliabue, Anna; Ferraris, Cinzia; Martinelli, Valentina; Pinelli, Giovanna; Repossi, Ilaria; Trentani, Claudia

2012-01-01

Weight preoccupations have been frequently reported in normal-weight subjects. Subthreshold anorexia nervosa (s-AN, all DSM IV TR criteria except amenorrhea or underweight) is a form of eating disorder not otherwise specified that has received scarce scientific attention. Under a case-control design we compared the general characteristics, body composition, and psychopathological features of normal-weight patients with s-AN with those of BMI- and sex-matched controls. Participants in this pilot study included 9 normal-weight women who met the DSM IV TR criteria for s-AN and 18 BMI-matched normal-weight controls. The general characteristics of the study participants were collected by questionnaire. Body composition was measured by bioelectrical impedance. Behavioral and psychological measures included the standardized symptom checklist (SCL-90-R) and the eating disorder inventory (EDI-2). There were no differences in age, education, employment status, marital status, and history of previous slimming treatment in the two study groups. In addition, anthropometric measures and body composition of s-AN patients and BMI-matched normal weight controls were not significantly different. In the s-AN subgroup, we found a significant relationship between waist circumference and the SCL-90-R obsessivity-compulsivity scale (n=9, r=-0.69, p<0.05). After multiple regression analysis, the SCL-90-R obsessivity-compulsivity scale (beta = 0.61, t=2.7, p=0.017) was the only independent predictor of the presence s-AN in our study cohort. These pilot results suggest that psychopathological criteria (particularly related to the obsessivity-compulsivity dimension) may be more useful than anthropometric measures for screening of s-AN in normal-weight women.

Comparison of lateral abdominal muscle thickness between weightlifters and matched controls.

PubMed

Sitilertpisan, Patraporn; Pirunsan, Ubon; Puangmali, Aatit; Ratanapinunchai, Jonjin; Kiatwattanacharoen, Suchart; Neamin, Hudsaleark; Laskin, James J

2011-11-01

To compare lateral abdominal muscle thickness between weightlifters and matched controls. A case control study design. University laboratory. 16 female Thai national weightlifters and 16 matched controls participated in this study. Ultrasound imaging with a 12-MHz linear array was used to measure the resting thickness of transversus abdominis (TrA), internal oblique (IO) and total thickness (Total) of lateral abdominal muscle (LAM) on the right side of abdominal wall. The absolute muscle thickness and the relative contribution of each muscle to the total thickness were determined. Weightlifters had significantly thicker absolute TrA and IO muscles than matched controls (p < 0.01). Further, the relative thickness of the IO was significantly greater in weightlifters than matched controls (p < 0.05). The findings of this study suggest that routine Olympic style weight training among female weightlifters appears to result in preferential hypertrophy or adaptation of the IO muscle. Copyright © 2011 Elsevier Ltd. All rights reserved.

Racial/ethnic and educational differences in the estimated odds of recent nitrite use among adult household residents in the United States: an illustration of matching and conditional logistic regression.

PubMed

Delva, J; Spencer, M S; Lin, J K

2000-01-01

This article compares estimates of the relative odds of nitrite use obtained from weighted unconditional logistic regression with estimates obtained from conditional logistic regression after post-stratification and matching of cases with controls by neighborhood of residence. We illustrate these methods by comparing the odds associated with nitrite use among adults of four racial/ethnic groups, with and without a high school education. We used aggregated data from the 1994-B through 1996 National Household Survey on Drug Abuse (NHSDA). Difference between the methods and implications for analysis and inference are discussed.

Association Between Gout and Aortic Stenosis

PubMed Central

Chang, Kevin; Yokose, Chio; Tenner, Craig; Oh, Cheongeun; Donnino, Robert; Choy-Shan, Alana; Pike, Virginia C.; Shah, Binita D.; Lorin, Jeffrey D.; Krasnokutsky, Svetlana; Sedlis, Steven P.; Pillinger, Michael H.

2017-01-01

Background An independent association between gout and coronary artery disease is well established. The relationship between gout and valvular heart disease, however, is unclear. The aim of this study was to assess the association between gout and aortic stenosis. Methods We performed a retrospective case-control study. Aortic stenosis cases were identified through a review of outpatient transthoracic echocardiography (TTE) reports. Age-matched controls were randomly selected from patients who had undergone TTE and did not have aortic stenosis. Charts were reviewed to identify diagnoses of gout and the earliest dates of gout and aortic stenosis diagnosis. Results Among 1085 patients who underwent TTE, 112 aortic stenosis cases were identified. Cases and non-aortic stenosis controls (n=224) were similar in age and cardiovascular comorbidities. A history of gout was present in 21.4% (n=24) of aortic stenosis subjects compared with 12.5% (n=28) of controls (unadjusted OR 1.90, 95% CI 1.05–3.48, p=0.038). Multivariate analysis retained significance only for gout (adjusted OR 2.08, 95% CI 1.00–4.32, p=0.049). Among subjects with aortic stenosis and gout, gout diagnosis preceded aortic stenosis diagnosis by 5.8 ± 1.6 years. The age at onset of aortic stenosis was similar among patients with and without gout (78.7 ± 1.8 vs. 75.8 ± 1.0 years old, p=0.16). Conclusions Aortic stenosis patients had a markedly higher prevalence of precedent gout than age-matched controls. Whether gout is a marker of, or a risk factor for the development of aortic stenosis remains uncertain. Studies investigating the potential role of gout in the pathophysiology of aortic stenosis are warranted and could have therapeutic implications. PMID:27720853

Association Between Gout and Aortic Stenosis.

PubMed

Chang, Kevin; Yokose, Chio; Tenner, Craig; Oh, Cheongeun; Donnino, Robert; Choy-Shan, Alana; Pike, Virginia C; Shah, Binita D; Lorin, Jeffrey D; Krasnokutsky, Svetlana; Sedlis, Steven P; Pillinger, Michael H

2017-02-01

An independent association between gout and coronary artery disease is well established. The relationship between gout and valvular heart disease, however, is unclear. The aim of this study was to assess the association between gout and aortic stenosis. We performed a retrospective case-control study. Aortic stenosis cases were identified through a review of outpatient transthoracic echocardiography (TTE) reports. Age-matched controls were randomly selected from patients who had undergone TTE and did not have aortic stenosis. Charts were reviewed to identify diagnoses of gout and the earliest dates of gout and aortic stenosis diagnosis. Among 1085 patients who underwent TTE, 112 aortic stenosis cases were identified. Cases and nonaortic stenosis controls (n = 224) were similar in age and cardiovascular comorbidities. A history of gout was present in 21.4% (n = 24) of aortic stenosis subjects compared with 12.5% (n = 28) of controls (unadjusted odds ratio 1.90, 95% confidence interval 1.05-3.48, P = .038). Multivariate analysis retained significance only for gout (adjusted odds ratio 2.08, 95% confidence interval 1.00-4.32, P = .049). Among subjects with aortic stenosis and gout, gout diagnosis preceded aortic stenosis diagnosis by 5.8 ± 1.6 years. The age at onset of aortic stenosis was similar among patients with and without gout (78.7 ± 1.8 vs 75.8 ± 1.0 years old, P = .16). Aortic stenosis patients had a markedly higher prevalence of precedent gout than age-matched controls. Whether gout is a marker of, or a risk factor for, the development of aortic stenosis remains uncertain. Studies investigating the potential role of gout in the pathophysiology of aortic stenosis are warranted and could have therapeutic implications. Published by Elsevier Inc.

Entamoeba histolytica Infection in Female Sex Workers: A Matched Case-Control Study in Durango, Mexico.

PubMed

Alvarado-Esquivel, Cosme; Sanchez-Anguiano, Luis Francisco; Hernandez-Tinoco, Jesus; Estrada-Martinez, Sergio; Perez-Alamos, Alma Rosa; Ramos-Nevarez, Agar; Cerrillo-Soto, Sandra Margarita; Guido-Arreola, Carlos Alberto

2017-07-01

Infection with Entamoeba histolytica ( E. histolytica ) can be potentially transmitted by sexual contact. The seroepidemiology of E. histolytica in female sex workers has not been studied. The aim of the study was to determine whether E. histolytica is associated with the occupation of female sex work. In addition, the correlates of E. histolytica seroprevalence in female sex workers were also investigated. We performed an age- and gender-matched case-control study of 187 female sex workers and 374 women without sex work. Cases and controls were tested for the presence of E. histolytica IgG antibodies using a commercially available enzyme-linked immunoassay. Seroprevalence association with the characteristics of female sex workers was determined by bivariate analysis. Anti- E. histolytica IgG antibodies were found in five (2.7%) of 187 female sex workers and in 16 (4.3%) of 374 controls (odds ratios (OR) = 0.61; 95% confidence intervals (CI): 0.22 - 1.70; P = 0.34). Mean optical density of the immunoassay in seropositive cases and controls was 1.35 ± 0.93 and 0.73 ± 0.45, respectively (P = 0.05). Seroprevalence of E. histolytica infection did not vary significantly with age, education, socioeconomic level, or health status of sex workers. Seropositivity to E. histolytica did not correlate with work characteristics such as duration in the occupation, condom use, type of sex, or a history of sexually transmitted diseases, or with behavioral variables such as washing hands before eating, or consumption of untreated water. Results indicate that female sex workers do not have an increased risk for E. histolytica infection in Durango City, Mexico. Further studies to determine the risk of infection with E. histolytica by sexual contact should be conducted.

Entamoeba histolytica Infection in Female Sex Workers: A Matched Case-Control Study in Durango, Mexico

PubMed Central

Alvarado-Esquivel, Cosme; Sanchez-Anguiano, Luis Francisco; Hernandez-Tinoco, Jesus; Estrada-Martinez, Sergio; Perez-Alamos, Alma Rosa; Ramos-Nevarez, Agar; Cerrillo-Soto, Sandra Margarita; Guido-Arreola, Carlos Alberto

2017-01-01

Background Infection with Entamoeba histolytica (E. histolytica) can be potentially transmitted by sexual contact. The seroepidemiology of E. histolytica in female sex workers has not been studied. The aim of the study was to determine whether E. histolytica is associated with the occupation of female sex work. In addition, the correlates of E. histolytica seroprevalence in female sex workers were also investigated. Methods We performed an age- and gender-matched case-control study of 187 female sex workers and 374 women without sex work. Cases and controls were tested for the presence of E. histolytica IgG antibodies using a commercially available enzyme-linked immunoassay. Seroprevalence association with the characteristics of female sex workers was determined by bivariate analysis. Results Anti-E. histolytica IgG antibodies were found in five (2.7%) of 187 female sex workers and in 16 (4.3%) of 374 controls (odds ratios (OR) = 0.61; 95% confidence intervals (CI): 0.22 - 1.70; P = 0.34). Mean optical density of the immunoassay in seropositive cases and controls was 1.35 ± 0.93 and 0.73 ± 0.45, respectively (P = 0.05). Seroprevalence of E. histolytica infection did not vary significantly with age, education, socioeconomic level, or health status of sex workers. Seropositivity to E. histolytica did not correlate with work characteristics such as duration in the occupation, condom use, type of sex, or a history of sexually transmitted diseases, or with behavioral variables such as washing hands before eating, or consumption of untreated water. Conclusions Results indicate that female sex workers do not have an increased risk for E. histolytica infection in Durango City, Mexico. Further studies to determine the risk of infection with E. histolytica by sexual contact should be conducted. PMID:28611864

Residential traffic density and childhood leukemia risk.

PubMed

Von Behren, Julie; Reynolds, Peggy; Gunier, Robert B; Rull, Rudolph P; Hertz, Andrew; Urayama, Kevin Y; Kronish, Daniel; Buffler, Patricia A

2008-09-01

Exposures to carcinogenic compounds from vehicle exhaust may increase childhood leukemia risk, and the timing of this exposure may be important. We examined the association between traffic density and childhood leukemia risk for three time periods: birth, time of diagnosis, and lifetime average, based on complete residential history in a case-control study. Cases were rapidly ascertained from participating hospitals in northern and central California between 1995 and 2002. Controls were selected from birth records, individually matched on age, sex, race, and Hispanic ethnicity. Traffic density was calculated by estimating total vehicle miles traveled per square mile within a 500-foot (152 meter) radius area around each address. We used conditional logistic regression analyses to account for matching factors and to adjust for household income. We included 310 cases of acute lymphocytic leukemias (ALL) and 396 controls in our analysis. The odds ratio for ALL and residential traffic density above the 75th percentile, compared with subjects with zero traffic density, was 1.17 [95% confidence interval (95% CI), 0.76-1.81] for residence at diagnosis and 1.11 (95% CI, 0.70-1.78) for the residence at birth. For average lifetime traffic density, the odds ratio was 1.24 (95% CI, 0.74-2.08) for the highest exposure category. Living in areas of high traffic density during any of the exposure time periods was not associated with increased risk of childhood ALL in this study.

Outcomes of preterm neonates with frontal horn cysts: a retrospective study.

PubMed

Trawber, Rory; Rao, Shripada; Srinivasjois, Ravisha; Thonell, Sven; Nagarajan, Lakshmi; French, Noel; Jacoby, Peter; McMichael, Judy

2010-11-01

Isolated paraventricular frontal horn cysts are sometimes encountered on cranial ultrasound examinations of preterm neonates. The etiology and clinical significance of these lesions are unclear. The authors aimed to identify antenatal/intrapartum risk factors associated with the occurrence of these cysts and to assess developmental outcomes of preterm neonates with isolated frontal horn cysts. A retrospective cohort study with matched control design was used. A total of 28 cases were matched for gestation with 56 controls. No antenatal/intrapartum factors were associated with these cysts. At corrected age of 1 year, there was no difference in the mean general quotient between cases and controls (97.75 ± 17.28 vs 94.94 ± 9.86; P = .410). In all, 1 case and no controls had a diagnosis of cerebral palsy and 1 case and 3 controls had general quotients less than 80. The authors conclude that isolated paraventricular frontal horn cysts are benign, with no effect on neurodevelopment.

Cost Analysis of an Intervention to Prevent Methicillin-Resistant Staphylococcus Aureus (MRSA) Transmission.

PubMed

Chowers, Michal; Carmeli, Yehuda; Shitrit, Pnina; Elhayany, Asher; Geffen, Keren

2015-01-01

Our objective was to assess the cost implications of a vertical MRSA prevention program that led to a reduction in MRSA bacteremia. We performed a matched historical cohort study and cost analysis in a single hospital in Israel for the years 2005-2011. The cost of MRSA bacteremia was calculated as total hospital cost for patients admitted with bacteremia and for patients with hospital-acquired bacteremia, the difference in cost compared to matched controls. The cost of prevention was calculated as the sum of the cost of microbiology tests, single-use equipment used for patients in isolation, and infection control personnel. An average of 20,000 patients were screened yearly. The cost of prevention was $208,100 per year, with the major contributor being laboratory cost. We calculated that our intervention averted 34 cases of bacteremia yearly: 17 presenting on admission and 17 acquired in the hospital. The average cost of a case admitted with bacteremia was $14,500, and the net cost attributable to nosocomial bacteremia was $9,400. Antibiotics contributed only 0.4% of the total disease management cost. When the annual cost of averted cases of bacteremia and that of prevention were compared, the intervention resulted in annual cost savings of $199,600. A vertical MRSA prevention program targeted at high-risk patients, which was highly effective in preventing bacteremia, is cost saving. These results suggest that allocating resources to targeted prevention efforts might be beneficial even in a single institution in a high incidence country.

Does Educational Preparation Match Professional Practice: The Case of Higher Education Policy Analysts

ERIC Educational Resources Information Center

Arellano, Eduardo C.; Martinez, Mario C.

2009-01-01

This study compares the extent to which higher education policy analysts and master's and doctoral faculty of higher education and public affairs programs match on a set of competencies thought to be important to higher education policy analysis. Analysts matched master's faculty in three competencies while analysts and doctoral faculty matched in…

Breast Reference Set Application: GeorgeTuszynski-Temple (2012) — EDRN Public Portal

Cancer.gov

As recommended by the review committee, we will analyze 30 invasive cancer cases and 30 benign controls from the EDRN breast reference set. Cases and controls should be selected that are Caucasian and post-menopausal. It is suggested that the Caucasian cases and controls match as closely as possible in regards to age and body mass index.

Are steroids useful to treat cerebral venous thrombosis?

PubMed

Canhão, Patrícia; Cortesão, Ana; Cabral, Marta; Ferro, José M; Stam, Jan; Bousser, Marie-Germaine; Barinagarrementeria, Fernando

2008-01-01

No randomized controlled trial has evaluated the efficacy of steroids in acute cerebral venous thrombosis (CVT). We aimed to analyze the effect of steroids on the outcome of patients in the International Study on Cerebral Veins and Dural Sinus Thrombosis (ISCVT). ISCVT is a prospective observational study that included 624 CVT patients. Death or dependence at 6 months was compared between cases (patients treated with steroids) and controls (patients not treated with steroids), using 3 designs: (1) Matched case-control study (each case matched with a control for prognostic factors); (2) Nonmatched case-control study of the ISCVT cohort; (3) Case-control study in different strata according to the number of poor prognostic variables in each patient. One hundred and fifty (24%) patients were treated with steroids. (1) In the matched case-control study, poor outcome was similar in the two groups of patients (26/146 versus 17/149, OR=1.7; 95% CI 0.9 to 3.3, P=0.119). (2) In the ISCVT cohort, no significant difference in poor outcomes was found whether patients were treated with steroids or not (26/146 versus 60/469, OR=1.5; 95% CI 0.9 to 2.4). Patients without parenchymal lesions treated with steroids had worse prognosis than those treated without steroids (8/45 versus 9/184, OR=4.2, 95% CI 1.6 to 11.6, P=0.008). (3) Treatment with steroids was not associated with a better outcome in any strata of patients according to the number of poor prognostic factors. Steroids in the acute phase of CVT were not useful and were detrimental in patients without parenchymal cerebral lesions. These results do not support the use of steroids in CVT (evidence level III).

Toxoplasmosis gondii and schizophrenia: a case control study in a low Toxoplasma gondii seroprevalence Mexican population

USDA-ARS?s Scientific Manuscript database

There are conflicting reports concerning the association of T. gondii infection and schizophrenia. Therefore, we determined such association in a Mexican population of Mestizo ethnicity. Through a case-control study design, 50 schizophrenic patients and 150 control subjects matched by gender, age, r...

Nonadherence with Employer-Mandated Sleep Apnea Treatment and Increased Risk of Serious Truck Crashes

PubMed Central

Burks, Stephen V.; Anderson, Jon E.; Bombyk, Matthew; Haider, Rebecca; Ganzhorn, Derek; Jiao, Xueyang; Lewis, Connor; Lexvold, Andrew; Liu, Hong; Ning, Jiachen; Toll, Alice; Hickman, Jeffrey S.; Mabry, Erin; Berger, Mark; Malhotra, Atul; Czeisler, Charles A.; Kales, Stefanos N.

2016-01-01

Study Objectives: To evaluate the effect of an employer-mandated obstructive sleep apnea (OSA) program on the risk of serious preventable truck crashes. Methods: Data are from the first large-scale, employer-mandated program to screen, diagnose, and monitor OSA treatment adherence in the US trucking industry. A retrospective analysis of cohorts was constructed: polysomnogram-diagnosed drivers (OSA positive n = 1,613, OSA negative n = 403) were matched to control drivers unlikely to have OSA (n = 2,016) on two factors affecting crash risk, experience-at-hire and length of job tenure; tenure was matched on the date of each diagnosed driver's polysomnogram. Auto-adjusting positive airway pressure (APAP) treatment was provided to all cases (i.e. OSA positive drivers); treatment adherence was objectively monitored. Cases were grouped by treatment adherence: “Full Adherence” (n = 682), “Partial Adherence” (n = 571), or “No Adherence” (n = 360). Preventable Department-of-Transportation-reportable crashes/100,000 miles were compared across study subgroups. Robustness was assessed. Results: After the matching date, “No Adherence” cases had a preventable Department of Transportation-reportable crash rate that was fivefold greater (incidence rate ratio = 4.97, 95% confidence interval: 2.09, 10.63) than that of matched controls (0.070 versus 0.014 per 100,000 miles). The crash rate of “Full Adherence” cases was statistically similar to controls (incidence rate ratio = 1.02, 95% confidence interval: 0.48, 2.04; 0.014 per 100,000 miles). Conclusions: Nontreatment-adherent OSA-positive drivers had a fivefold greater risk of serious preventable crashes, but were discharged or quit rapidly, being retained only one-third as long as other subjects. Thus, the mandated program removed risky nontreatment-adherent drivers and retained adherent drivers at the study firm. Current regulations allow nonadherent OSA cases to drive at another firm by keeping their diagnosis private. Commentary: A commentary on this article appears in this issue on page 961. Citation: Burks SV, Anderson JE, Bombyk M, Haider R, Ganzhorn D, Jiao X, Lewis C, Lexvold A, Liu H, Ning J, Toll A, Hickman JS, Mabry E, Berger M, Malhotra A, Czeisler CA, Kales SN. Nonadherence with employer-mandated sleep apnea treatment and increased risk of serious truck crashes. SLEEP 2016;39(5):967–975. PMID:27070139

Selection of Reference Gene Expression in a Schizophrenia Brain Cohort

PubMed Central

Weickert, Cynthia Shannon; Sheedy, Donna; Rothmond, Debora A.; Dedova, Irina; Fung, Samantha; Garrick, Therese; Wong, Jenny; Harding, Antony J.; Sivagnanansundaram, Sinthuja; Hunt, Clare; Duncan, Carlotta; Sundqvist, Nina; Tsai, Shan-Yuan; Anand, Jasna; Draganic, Daren; Harper, Clive

2010-01-01

Objective To conduct postmortem human brain research into the neuropathological basis of schizophrenia, it is critical to establish cohorts that are well-characterised and well-matched. Our objective was to determine if specimen characteristics, including: diagnosis, age, postmortem interval (PMI), brain acidity (pH), and/or the agonal state of the subject at death related to RNA quality, and to determine the most appropriate reference gene mRNAs. Methods We selected a matched cohort of 74 cases (37 schizophrenia / schizoaffective disorder cases and 37 controls cases). Middle frontal gyrus tissue was pulverised, tissue pH was measured, RNA isolated for cDNA from each case, and RNA integrity number (RIN) measurements were assessed. Using RT-PCR, we measured nine housekeeper genes and calculated a geomean in each diagnostic group. Results We found that the RINs were very good (mean 7.3) and all nine housekeeper control genes were significantly correlated with RIN. Seven of nine housekeeper genes were also correlated with pH, and two clinical variables, agonal state and duration of illness did have an effect on some control mRNAs. No major impact of PMI or freezer time on housekeeper mRNAs was detected. Our results show that people with schizophrenia had significantly less PPIA, and SDHA and tended to have less GUSB and B2M mRNA suggesting that these control genes may not be good candidates for normalisation. Conclusions In our cohort, less than 10% variability in RIN values was detected and the diagnostic groups were well matched overall. Our cohort was adequately powered (0.80–0.90) to detect mRNA differences (25%) due to disease. Our study suggests that multiple factors should be considered in mRNA expression studies of human brain tissues. When schizophrenia cases are adequately matched to control cases subtle differences in gene expression can be reliably detected. PMID:20073568

Factors influencing tackle injuries in rugby union football

PubMed Central

Garraway, W. M.; Lee, A. J.; Macleod, D. A.; Telfer, J. W.; Deary, I. J.; Murray, G. D.

1999-01-01

OBJECTIVES: To assess the influence of selected aspects of lifestyle, personality, and other player related factors on injuries in the tackle. To describe the detailed circumstances in which these tackles occurred. METHODS: A prospective case-control study was undertaken in which the tackling and tackled players ("the cases") involved in a tackle injury were each matched with "control" players who held the same respective playing positions in the opposing teams. A total of 964 rugby matches involving 71 senior clubs drawn from all districts of the Scottish Rugby Union (SRU) were observed by nominated linkmen who administered self report questionnaires to the players identified as cases and controls. Information on lifestyle habits, match preparation, training, and coaching experience was obtained. A validated battery of psychological tests assessed players' trait anger and responses to anger and hostility. The circumstances of the tackles in which injury occurred were recorded by experienced SRU coaching staff in interviews with involved players after the match. RESULTS: A total of 71 tackle injury episodes with correct matching of cases and controls were studied. The following player related factors did not contribute significantly to tackle injuries: alcohol consumption before the match, feeling "below par" through minor illness, the extent of match preparation, previous coaching, or practising tackling. Injured and non- injured players in the tackle did not differ in their disposition toward, or expression of, anger or hostility. Some 85% of tackling players who were injured were three quarters, and 52% of injuries occurred when the tackle came in behind the tackled player or within his peripheral vision. Either the tackling or tackled player was sprinting or running in all of these injury episodes. One third of injuries occurred in differential speed tackles--that is, when one player was travelling much faster than the other at impact. The player with the lower momentum was injured in 80% of these cases. Forceful or crunching tackles resulting in injury mostly occurred head on or within the tackled player's side vision. CONCLUSIONS: Attention should be focused on high speed tackles going in behind the tackled player's line of vision. Comparative information on the circumstances of the vast majority of tackles in which no injury occurs is required before any changes are considered to reduce injuries in the tackle. 


 PMID:10027056

Genome-scale case-control analysis of CD4+ T-cell DNA methylation in juvenile idiopathic arthritis reveals potential targets involved in disease.

PubMed

Ellis, Justine A; Munro, Jane E; Chavez, Raul A; Gordon, Lavinia; Joo, Jihoon E; Akikusa, Jonathan D; Allen, Roger C; Ponsonby, Anne-Louise; Craig, Jeffrey M; Saffery, Richard

2012-11-13

Juvenile Idiopathic Arthritis (JIA) is a complex autoimmune rheumatic disease of largely unknown cause. Evidence is growing that epigenetic variation, particularly DNA methylation, is associated with autoimmune disease. However, nothing is currently known about the potential role of aberrant DNA methylation in JIA. As a first step to addressing this knowledge gap, we have profiled DNA methylation in purified CD4+ T cells from JIA subjects and controls. Genomic DNA was isolated from peripheral blood CD4+ T cells from 14 oligoarticular and polyarticular JIA cases with active disease, and healthy age- and sex-matched controls. Genome-scale methylation analysis was carried out using the Illumina Infinium HumanMethylation27 BeadChip. Methylation data at >25,000 CpGs was compared in a case-control study design. Methylation levels were significantly different (FDR adjusted p<0.1) at 145 loci. Removal of four samples exposed to methotrexate had a striking impact on the outcome of the analysis, reducing the number of differentially methylated loci to 11. The methotrexate-naive analysis identified reduced methylation at the gene encoding the pro-inflammatory cytokine IL32, which was subsequently replicated using a second analysis platform and a second set of case-control pairs. Our data suggests that differential T cell DNA methylation may be a feature of JIA, and that reduced methylation at IL32 is associated with this disease. Further work in larger prospective and longitudinal sample collections is required to confirm these findings, assess whether the identified differences are causal or consequential of disease, and further investigate the epigenetic modifying properties of therapeutic regimens.

Automated Peak Detection and Matching Algorithm for Gas Chromatography–Differential Mobility Spectrometry

PubMed Central

Fong, Sim S.; Rearden, Preshious; Kanchagar, Chitra; Sassetti, Christopher; Trevejo, Jose; Brereton, Richard G.

2013-01-01

A gas chromatography–differential mobility spectrometer (GC-DMS) involves a portable and selective mass analyzer that may be applied to chemical detection in the field. Existing approaches examine whole profiles and do not attempt to resolve peaks. A new approach for peak detection in the 2D GC-DMS chromatograms is reported. This method is demonstrated on three case studies: a simulated case study; a case study of headspace gas analysis of Mycobacterium tuberculosis (MTb) cultures consisting of three matching GC-DMS and GC-MS chromatograms; a case study consisting of 41 GC-DMS chromatograms of headspace gas analysis of MTb culture and media. PMID:21204557

Endoscopic detection rate of sessile serrated lesions in Lynch syndrome patients is comparable with an age- and gender-matched control population: case-control study with expert pathology review.

PubMed

Vleugels, Jasper L A; Sahin, Husna; Hazewinkel, Yark; Koens, Lianne; van den Berg, Jose G; van Leerdam, Monique E; Dekker, Evelien

2018-05-01

Carcinogenesis in Lynch syndrome involves fast progression of adenomas to colorectal cancer (CRC) because of microsatellite instability. The role of sessile serrated lesions (SSLs) and the serrated neoplasia pathway in these patients is unknown. The aim of this matched case-control study was to compare endoscopic detection rates and distribution of SSLs in Lynch syndrome patients with a matched control population. We collected data of Lynch syndrome patients with a proven germline mutation who underwent colonoscopy between January 2011 and April 2016 in 2 tertiary referral hospitals. Control subjects undergoing elective colonoscopy from 2011 and onward for symptoms or surveillance were selected from a prospectively collected database. Patients were matched 1:1 for age, gender, and index versus surveillance colonoscopy. An expert pathology review of serrated polyps was performed. The primary outcomes included the detection rates and distribution of SSLs. We identified 321 patients with Lynch syndrome who underwent at least 1 colonoscopy. Of these, 223 Lynch syndrome patients (mean age, 49.3; 59% women; index colonoscopy, 56%) were matched to 223 control subjects. SSLs were detected in 7.6% (95% confidence interval, 4.8-11.9) of colonoscopies performed in Lynch syndrome patients and in 6.7% (95% confidence interval, 4.1-10.8) of control subjects (P = .86). None of the detected SSLs in Lynch syndrome patients contained dysplasia. The detection rate of SSLs in Lynch syndrome patients undergoing colonoscopy is comparable with a matched population. These findings suggest that the role of the serrated neoplasia pathway in CRC development in Lynch syndrome seems to be comparable with that in the general population. Copyright © 2018 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

``Carbon Credits'' for Resource-Bounded Computations Using Amortised Analysis

NASA Astrophysics Data System (ADS)

Jost, Steffen; Loidl, Hans-Wolfgang; Hammond, Kevin; Scaife, Norman; Hofmann, Martin

Bounding resource usage is important for a number of areas, notably real-time embedded systems and safety-critical systems. In this paper, we present a fully automatic static type-based analysis for inferring upper bounds on resource usage for programs involving general algebraic datatypes and full recursion. Our method can easily be used to bound any countable resource, without needing to revisit proofs. We apply the analysis to the important metrics of worst-case execution time, stack- and heap-space usage. Our results from several realistic embedded control applications demonstrate good matches between our inferred bounds and measured worst-case costs for heap and stack usage. For time usage we infer good bounds for one application. Where we obtain less tight bounds, this is due to the use of software floating-point libraries.

A population-based study on the association between chronic periodontitis and sialolithiasis.

PubMed

Hung, Shih-Han; Huang, Hung-Meng; Lee, Hsin-Chien; Ching Lin, Herng; Kao, Li-Ting; Wu, Chuan-Song

2016-04-01

Whereas the impression that poor oral hygiene is linked to the development of sialolithiasis may be widely accepted, very few studies provide evidence to support this. This study therefore aimed to evaluate the association between chronic periodontitis (CP) and the subsequent development of salivary gland stone based on a nationwide coverage database. A case-control study. A total of 987 subjects with sialolithiasis were included as cases. In a ratio of five controls per case, 4,935 controls matched in terms of sex and age group were selected. Conditional logistic regression analysis was performed to determine the possible association of sialolithiasis with previously diagnosed CP. The prevalence of prior CP between cases and controls demonstrated that 1,831 (30.9%) out of the 5,922 sampled subjects had prior CP. By Chi-square test, there was a significant difference in the prevalence of prior CP between the cases and controls (36.8% vs. 29.7%, P < 0.001). By conditional logistic regression analysis, the odds ratio (OR) of prior CP for cases was 1.37 (95% confidence interval [CI], 1.19-1.56) compared to the controls after adjusting for geographic location and tobacco use. Further analyzing the relationship between sialolithiasis and prior CP according to sex, sialolithiasis was associated with prior CP regardless of sex. The adjusted OR of prior CP for the cases was 1.34 (95% CI, 1.10-1.64) and 1.41 (95% CI, 1.15-1.73) for males and females, respectively, when compared to controls. This study demonstrates an association between CP and sialolithiasis. 3b. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.

Effectiveness of 23-valent pneumococcal polysaccharide vaccine and seasonal influenza vaccine for pneumonia among the elderly - Selection of controls in a case-control study.

PubMed

Kondo, Kyoko; Suzuki, Kanzo; Washio, Masakazu; Ohfuji, Satoko; Fukushima, Wakaba; Maeda, Akiko; Hirota, Yoshio

2017-08-24

We conducted a case-control study to elucidate associations between pneumonia in elderly individuals and 23-valent pneumococcal polysaccharide vaccine (PPSV23) and seasonal influenza vaccine (influenza vaccine). Here, we examined selection of controls in our study using an analytic epidemiology approach. The study period was from October 1, 2009 through September 30, 2014. Cases comprised ≥65-year-old patients newly diagnosed with pneumonia. For every case with pneumonia, two patients with other diseases (one respiratory medicine, one non-respiratory medicine) who were sex-, age-, visit date- and visit hospital-matched were selected as controls. Odds ratios (ORs) and 95% confidence intervals (CIs) of vaccination for pneumonia were calculated using conditional logistic regression model. Similar analyses were also conducted based on the clinical department of controls. Analysis was conducted in 234 cases and 438 controls. Effectiveness of pneumococcal vaccination or influenza vaccination against pneumonia was not detected. Proportions of either vaccination in controls were greater among respiratory medicine (pneumococcal vaccine, 38%; influenza vaccine, 55%) than among non-respiratory medicine (23%; 48%). Analysis using controls restricted to respiratory medicine showed marginally significant effectiveness of pneumococcal vaccination (OR, 0.59; 95%CI, 0.34-1.03; P=0.064) and influenza vaccination (0.64; 0.40-1.04; 0.072). However, this effectiveness might have been overestimated by selection bias of controls, as pneumonia cases are not necessarily respiratory medicine patients. In the analysis using controls restricted to non-respiratory medicine, OR of pneumococcal vaccination for pneumonia was close to 1, presumably because the proportion of pneumococcal vaccination was higher in cases than in controls. Because pneumococcal vaccine was not routinely administered during the study period, differences in recommendations of vaccination by physician in different clinical departments might have greatly affected vaccination proportions. When we select controls, we should consider the background factors (underlying diseases, clinical department, etc.) which affect physicians' recommendation of vaccination. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Pharmaceutical industry research and cost savings in community-acquired pneumonia.

PubMed

Kessler, Lori A; Waterer, Grant W; Barca, Robin; Wunderink, Richard G

2002-09-01

To provide financial justification for continuing pharmaceutical research in an environment that has met with increasing resistance from insurance carriers to paying for the care of patients enrolled in research studies. Matched case-control study of patients enrolled into inpatient community-acquired pneumonia (CAP) pharmaceutical research protocols. Case patients were enrolled into a CAP pharmaceutical research trial. Control patients were obtained from a prospective cohort study of CAP. Cases were matched to controls on the basis of age, sex, pneumonia severity index (PSI) grade, and comorbid illnesses as measured by the PSI and Acute Physiologic and Chronic Health Evaluation II (APACHE II) scoring systems. Financial data were obtained from hospital billing records. Twenty-five cases were identified and matched to appropriate controls. There was no statistically significant difference in mean PSI and APACHE II scores between cases and controls. There was a significant reduction in the total charges for hospital care of patients enrolled into a pharmaceutical industry trial ($6267 vs $9979; P = .03). As expected, the most dramatic reduction was in pharmacy charges ($642 vs $1797; P = .002), but there were trends toward lower charges in all cost subgroups. Interestingly, there was also a strong trend toward reduced length of hospital stay associated with enrollment in a pharmaceutical trial (4.5 vs 6.0 days; P = .06). Enrollment in a pharmaceutical research protocol results in significant cost savings in patients admitted to the hospital with CAP and may lead to earlier hospital discharge.

Retrospective multicenter matched case-control study on the risk factors for narcolepsy with special focus on vaccinations (including pandemic influenza vaccination) and infections in Germany.

PubMed

Oberle, Doris; Pavel, Jutta; Mayer, Geert; Geisler, Peter; Keller-Stanislawski, Brigitte

2017-06-01

Studies associate pandemic influenza vaccination with narcolepsy. In Germany, a retrospective, multicenter, matched case-control study was performed to identify risk factors for narcolepsy, particularly regarding vaccinations (seasonal and pandemic influenza vaccination) and infections (seasonal and pandemic influenza) and to quantify the detected risks. Patients with excessive daytime sleepiness who had been referred to a sleep center between April 2009 and December 2012 for multiple sleep latency test (MSLT) were eligible. Case report forms were validated according to the criteria for narcolepsy defined by the Brighton Collaboration (BC). Confirmed cases of narcolepsy (BC level of diagnostic certainty 1-4a) were matched with population-based controls by year of birth, gender, and place of residence. A second control group was established including patients in whom narcolepsy was definitely excluded (test-negative controls). A total of 103 validated cases of narcolepsy were matched with 264 population-based controls. The second control group included 29 test-negative controls. A significantly increased odd ratio (OR) to develop narcolepsy (crude OR [cOR] = 3.9, 95% confidence interval [CI] = 1.8-8.5; adjusted OR [aOR] = 4.5, 95% CI = 2.0-9.9) was detected in individuals immunized with pandemic influenza A/H1N1/v vaccine prior to symptoms onset as compared to nonvaccinated individuals. Using test-negative controls, in individuals immunized with pandemic influenza A/H1N1/v vaccine prior to symptoms onset, a nonsignificantly increased OR of narcolepsy was detected when compared to nonvaccinated individuals (whole study population, BC levels 1-4a: cOR = 1.9, 95% CI = 0.5-6.9; aOR = 1.8, 95% CI = 0.3-10.1). The findings of this study support an increased risk for narcolepsy after immunization with pandemic influenza A/H1N1/v vaccine. Copyright © 2017 Elsevier B.V. All rights reserved.

Folate and Breast Cancer: Role of Intake, Blood Levels, and Metabolic Gene Polymorphisms

DTIC Science & Technology

2006-06-01

polymorphisms . The specific aims are 1) methodological training in the analysis of gene - gene and gene -environment interactions by studying folate...evaluation of folate intake, plasma folate, and metabolic gene polymorphisms in relation to breast cancer risk: Months 1-19. b. Prepare blood samples...isolated for the folate and gene polymorphism assays among the 184 cases and matched controls. The folate assays are on-going at this time and over

Return to Play and Decreased Performance After Anterior Cruciate Ligament Reconstruction in National Football League Defensive Players.

PubMed

Read, Connor R; Aune, Kyle T; Cain, E Lyle; Fleisig, Glenn S

2017-07-01

Anterior cruciate ligament (ACL) injuries occur commonly in football. Recent work has reported ACL reconstruction (ACLR) as one of several orthopaedic procedures with unfavorable outcomes for professional athletes. The performance impact to defensive players after surgery has not been quantified. To quantify the effect of ACLR on the performance of defensive players by comparing them to a cohort of matched controls as well as to measure the effect of ACLR on athletes' career length in the National Football League (NFL). Case-control and cohort study; Level of evidence, 3. Thirty-eight NFL defensive players with a history of ACLR from 2006 to 2012 were identified. For each injured player, a matched control player was identified. Demographic and performance statistics were collected from the online NFL player database. Players who returned after ACLR (n = 23) were compared with players who did not return (n = 15) using t tests and chi-squared analyses. Similarly, players who returned after ACLR (n = 23) were compared with their matched controls with t tests and chi-squared analyses. Two-way repeated-measures analysis of variance was utilized to test for significant differences between performance before and after the season of the injury for the players in the ACLR group who returned (n = 23) and for their matched controls. Kaplan-Meier analysis was performed to test for differences in the rate of retirement between the groups. For all analyses, P values <.05 were considered significant. Approximately 74% (28/38) of athletes who underwent ACLR returned to play at least 1 NFL game, and 61% (23/38) successfully returned to play at least half a season (ie, 8 games). Athletes in the ACLR group who returned retired from the NFL significantly sooner and more often after surgery than their matched controls. In the seasons leading up to their injury, athletes who successfully returned to play started a greater percentage of their games (81%) and made more solo tackles per game (3.44 ± 1.47) compared with athletes in the ACLR group who did not return to play (54% and 1.82 ± 1.17, respectively) and compared with healthy control players (52% and 1.77 ± 1.19, respectively). After the season of surgery, athletes in the ACLR group who returned to play decreased to 57% games started and 2.38 ± 1.24 solo tackles per game, while their matched controls suffered no significant decreases. Players who successfully returned were above-average NFL players before their injury but comparatively average after their return.

Psychosocial and Psychiatric Factors Associated with Adolescent Suicide: A Case-Control Psychological Autopsy Study

ERIC Educational Resources Information Center

Portzky, Gwendolyn; Audenaert, Kurt; van Heeringen, Kees

2009-01-01

This study aimed at the investigation of psychosocial and psychiatric risk factors of adolescent suicide by means of a case-control psychological autopsy study. Relatives and other informants of 19 suicide victims and 19 matched psychiatric controls were interviewed by means of a semi-structured interview schedule. Psychiatric controls included…

Dyslipidaemia in woman with polycystic ovarian syndrome: a case control study in tertiary care hospital of Karachi.

PubMed

Hussain, Amna; Alam, Junaid Mahmood

2014-09-01

To compare lipid profile in lean and obese women with polycystic ovary syndrome with normal weight and obese controls. The case-control study was conducted at the Department of Chemical Pathology, Liaquat National Hospital, Karachi, from March 2006 to April 2007. It comprised 50 cases of polycystic ovary syndrome along with 50 healthy controls matching for age, gender and weight. SPSS 14 was used for statistical analysis. The mean fasting levels of triglyceride and Low density lipoprotein cholesterol were considerably higher in women with polycystic ovary syndrome than those in the control group (p < 0.05), while high-density lipoprotein cholesterolwas significantly low in patients than the controls (p <0.001). Obese patients had high triglyceride value (p < 0.05). There was significant interaction between polycystic ovary syndrome, obesity and triglyceride levels (p < 0.05). Polycystic ovary syndrome is associated with a more pronounced atherogenic lipid profile. Lipid parameters were adversely affected in a subgroup that was obese. As such, women with polycystic ovary syndrome are at high risk of developing cardiovascular disease due to the presence of dyslipidaemia.

Nitrate in drinking water and risk of death from pancreatic cancer in Taiwan.

PubMed

Yang, Chun-Yuh; Tsai, Shang-Shyue; Chiu, Hui-Fen

2009-01-01

The relationship between nitrate levels in drinking water and risk of pancreatic cancer development remains inconclusive. A matched case-control and nitrate ecology study was used to investigate the association between mortality attributed to pancreatic cancer and nitrate exposure from Taiwan's drinking water. All pancreatic cancer deaths of Taiwan residents from 2000 through 2006 were obtained from the Bureau of Vital Statistics of the Taiwan Provincial Department of Health. Controls were deaths from other causes and were pair-matched to the cases by gender, year of birth, and year of death. Each matched control was selected randomly from the set of possible controls for each case. Data on nitrate-nitrogen (NO(3)-N) levels of drinking water throughout Taiwan were collected from Taiwan Water Supply Corporation (TWSC). The municipality of residence for cancer cases and controls was assumed to be the source of the subject's nitrate exposure via drinking water. The adjusted odds ratios and confidence limits for pancreatic cancer death for those with high nitrate levels in their drinking water, as compared to the lowest tertile, were 1.03 (0.9-1.18) and 1.1 (0.96-1.27), respectively. The results of the present study show that there was no statistically significant association between the levels of nitrate in drinking water and increased risk of death from pancreatic cancer.

Phenoxy herbicides and chlorophenols: a case control study on soft tissue sarcoma and malignant lymphoma.

PubMed Central

Smith, J. G.; Christophers, A. J.

1992-01-01

A case control study on patients with soft tissue sarcoma and malignant lymphoma was undertaken to test whether there was any association between these diseases and past exposure to chlorinated phenoxy acid herbicides or chlorophenols. It was carried out over the period 1982-1988 in Victoria, Australia. Thirty males with soft tissue sarcoma and 52 males with malignant lymphoma were matched by age, place of residence and sex with one population control and one cancer control each. Exposure was assessed by personal interviews conducted by an occupational hygienist. Exposures within 5 years prior to diagnosis of each matched case were ignored, both for the cases and their matched controls. The estimated relative risks for definite or probable exposure to chlorinated phenoxy compounds or chlorophenols for at least 1 day were 1.0 (95% confidence interval (CI): 0.3-3.1) for soft tissue sarcoma and 1.5 (95% CI: 0.6-3.7) for malignant lymphoma. When the criterion for exposure was raised to more than 30 days, the estimated relative risks were 2.0 (95% CI: 0.5-8.0) for soft tissue sarcoma and 2.7 (95% CI: 0.7-9.6) for malignant lymphoma. Additional analyses were carried out for exposure of at least 1 day to phenoxy herbicides alone or chlorophenols alone. None of the estimated relative risks was significantly greater than unity. PMID:1558802

Feasibility of reusing time-matched controls in an overlapping cohort.

PubMed

Delcoigne, Bénédicte; Hagenbuch, Niels; Schelin, Maria Ec; Salim, Agus; Lindström, Linda S; Bergh, Jonas; Czene, Kamila; Reilly, Marie

2018-06-01

The methods developed for secondary analysis of nested case-control data have been illustrated only in simplified settings in a common cohort and have not found their way into biostatistical practice. This paper demonstrates the feasibility of reusing prior nested case-control data in a realistic setting where a new outcome is available in an overlapping cohort where no new controls were gathered and where all data have been anonymised. Using basic information about the background cohort and sampling criteria, the new cases and prior data are "aligned" to identify the common underlying study base. With this study base, a Kaplan-Meier table of the prior outcome extracts the risk sets required to calculate the weights to assign to the controls to remove the sampling bias. A weighted Cox regression, implemented in standard statistical software, provides unbiased hazard ratios. Using the method to compare cases of contralateral breast cancer to available controls from a prior study of metastases, we identified a multifocal tumor as a risk factor that has not been reported previously. We examine the sensitivity of the method to an imperfect weighting scheme and discuss its merits and pitfalls to provide guidance for its use in medical research studies.

Risk factors for acquisition of OXA-48-producing Klebsiella pneumonia among contact patients: a multicentre study.

PubMed

Hilliquin, D; Le Guern, R; Thepot Seegers, V; Neulier, C; Lomont, A; Marie, V; Legeay, C; Merrer, J; Lepelletier, D; Rogues, A M; Grandbastien, B; Lucet, J C; Zahar, J R

2018-03-01

Cohorting carbapenemase-producing Enterobacteriaceae (CPE) carriers during hospitalization limits in-hospital spreading. To identify risk factors for CPE acquisition among contacts of an index patient in non-cohorted populations. A multicentre retrospective matched case-control study was conducted in five hospitals. Each contact patient (case) who acquired Klebsiella pneumoniae (KP)-OXA-48 from an index patient was compared to three contact (controls) with the same index patients matched with hospitalization in the same unit and similar exposure times. Fifty-one secondary cases and 131 controls were included. By univariate analysis, exposure time (odds ratio: 1.06; 95% confidence interval: 1.02-1.1; P = 0.006), concomitant infection at admission (3.23; 1.42-7.35; P = 0.005), antimicrobial therapy within the last month before hospitalization (2.88; 1.34-6.2; P = 0.007), antimicrobial therapy during the exposure time (5.36; 2.28-12.6; P < 0.001), use of at least one invasive procedure (2.99; 1.25-7.15; P = 0.014), number of invasive procedures (1.52; 1.05-2.19; P = 0.025), and geographical proximity (2.84; 1.15-7.00; P = 0.023) were associated with CPE acquisition. By multivariate analysis, antimicrobial therapy during the exposure time (odds ratio: 6.36; 95% confidence interval: 2.46-16.44; P < 0.001), at least one invasive procedure (2.92; 1.04-8.17; P = 0.041), and geographical proximity (3.69; 1.15-11.86; P = 0.028) were associated with acquisition. In this study, geographical proximity, invasive procedure, and antimicrobial therapy during exposure time were significantly associated with KP-OXA-48 acquisition. Copyright © 2017 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

Differential effects of saturated fatty acids on the risk of metabolic syndrome: a matched case-control and meta-analysis study.

PubMed

Yang, Wei-Sin; Chen, Pei-Chun; Hsu, Hsiu-Ching; Su, Ta-Chen; Lin, Hung-Ju; Chen, Ming-Fong; Lee, Yuan-Teh; Chien, Kuo-Liong

2018-06-01

We investigated the association between plasma saturated fatty acids (SFAs) and the risk of metabolic syndrome among ethnic Chinese adults in Taiwan who attended a health check-up center. A case-control study based on 1000 cases of metabolic syndrome and 1:1 matched control participants (mean age, 54.9 ± 10.7 y; 36% females) were recruited. Metabolic syndrome was defined according to the criteria of the International Diabetes Federation. Gas chromatography was used to measure the distribution of fatty acids in plasma (% of total fatty acids). Even-chain SFAs, including 14:0, 16:0, and 18:0, were associated with metabolic syndrome; the adjusted odds ratio [OR] and 95% confidence interval [CI] per standard deviation [SD] difference was 3.32, [1.98-5.59]; however, very-long-chain SFAs, including 20:0, 21:0, 22:0, 23:0, and 24:0, were inversely associated with metabolic syndrome. The adjusted OR [95% CI] per SD difference was 0.67 [0.58-0.78]. The area under the receiver operative characteristic curve increased from 0.814 in the basic model to 0.815 (p = 0.54, compared with the basic model), 0.818 (p < 0.0001), and 0.820 (p < 0.0001) after adding odd-chain, even-chain, and very-long chain SFAs. A meta-analysis based on 12 studies showed that the summarized OR for type 2 diabetes mellitus was 1.16 [0.96-1.41] for the top versus bottom SFAs. Different carbon numbers of SFAs have been shown to have differential effects on the status of metabolic syndrome, implying that SFAs are not homogenous for the effects. Copyright © 2018 Elsevier Inc. All rights reserved.

DNA Damage Analysis in Children with Non-syndromic Developmental Delay by Comet Assay.

PubMed

Susai, Surraj; Chand, Parkash; Ballambattu, Vishnu Bhat; Hanumanthappa, Nandeesha; Veeramani, Raveendranath

2016-05-01

Majority of the developmental delays in children are non-syndromic and they are believed to have an underlying DNA damage, though not well substantiated. Hence the present study was carried out to find out if there is any increased DNA damage in children with non-syndromic developmental delay by using the comet assay. The present case-control study was undertaken to assess the level of DNA damage in children with non syndromic developmental delay and compare the same with that of age and sex matched controls using submarine gel electrophoresis (Comet Assay). The blood from clinically diagnosed children with non syndromic developmental delay and controls were subjected for alkaline version of comet assay - Single cell gel electrophoresis using lymphocytes isolated from the peripheral blood. The comets were observed under a bright field microscope; photocaptured and scored using the Image J image quantification software. Comet parameters were compared between the cases and controls and statistical analysis and interpretation of results was done using the statistical software SPSS version 20. The mean comet tail length in cases and control was 20.77+7.659μm and 08.97+4.398μm respectively which was statistically significant (p<0.001). Other comet parameters like total comet length and % DNA in tail also showed a statistically significant difference (p < 0.001) between cases and controls. The current investigation unraveled increased levels of DNA damage in children with non syndromic developmental delay when compared to the controls.

Volumetric analysis of cerebellum in short-track speed skating players.

PubMed

Park, In Sung; Lee, Nam Joon; Kim, Tae-Young; Park, Jin-Hoon; Won, Yu-Mi; Jung, Yong-Ju; Yoon, Jin-Hwan; Rhyu, Im Joo

2012-12-01

The cerebellum is associated with balance control and coordination, which might be important for gliding on smooth ice at high speeds. A number of case studies have shown that cerebellar damage induces impaired balance and coordination. As a positive model, therefore, we investigated whether plastic changes in the volumes of cerebellar subregions occur in short-track speed skating players who must have extraordinary abilities of balance and coordination, using three-dimensional magnetic resonance imaging volumetry. The manual tracing was performed and the volumes of cerebellar hemisphere and vermian lobules were compared between short-track speed skating players (n=16) and matched healthy controls (n=18). We found larger right cerebellar hemisphere volume and vermian lobules VI-VII (declive, folium, and tuber) in short-track speed skating players in comparison with the matched controls. The finding suggests that the specialized abilities of balance and coordination are associated with structural plasticity of the right hemisphere of cerebellum and vermian VI-VII and these regions play an essential role in balance and coordination.

Case-control study on uveal melanoma (RIFA): rational and design

PubMed Central

Schmidt-Pokrzywniak, Andrea; Jöckel, Karl-Heinz; Bornfeld, Norbert; Stang, Andreas

2004-01-01

Background Although a rare disease, uveal melanoma is the most common primary intraocular malignancy in adults, with an incidence rate of up to 1.0 per 100,000 persons per year in Europe. Only a few consistent risk factors have been identified for this disease. We present the study design of an ongoing incident case-control study on uveal melanoma (acronym: RIFA study) that focuses on radiofrequency radiation as transmitted by radio sets and wireless telephones, occupational risk factors, phenotypical characteristics, and UV radiation. Methods/Design We conduct a case-control study to identify the role of different exposures in the development of uveal melanoma. The cases of uveal melanoma were identified at the Division of Ophthalmology, University of Essen, a referral centre for tumours of the eye. We recruit three control groups: population controls, controls sampled from those ophthalmologists who referred cases to the Division of Ophthalmology, University of Duisburg-Essen, and sibling controls. For each case the controls are matched on sex and age (five year groups), except for sibling controls. The data are collected from the study participants by short self-administered questionnaire and by telephone interview. During and at the end of the field phase, the data are quality-checked. To estimate the effect of exposures on uveal melanoma risk, we will use conditional logistic regression that accounts for the matching factors and allows to control for potential confounding. PMID:15318944

Natural history and clinical detection of undiagnosed coeliac disease in a North American community.

PubMed

Hujoel, I A; Van Dyke, C T; Brantner, T; Larson, J; King, K S; Sharma, A; Murray, J A; Rubio-Tapia, A

2018-05-01

Coeliac disease is a substantially underdiagnosed disorder, with clinical testing currently guided by case finding. To determine the presence of indications for diagnostic testing and frequency of clinical testing in undiagnosed coeliac disease. This was a case-control study of adults without prior diagnosis of coeliac disease. Undiagnosed cases were identified through sequential serology, and unaffected age- and gender-matched controls were selected. Medical records were systematically reviewed for indications for and evidence of clinical testing. Of 47 557 adults, 408 cases of undiagnosed coeliac disease were identified. 408 serology negative matched controls were selected. Eight-matched pairs were excluded, leading to 800 included individuals (61% female; median age 44.2 years). The odds of any indication for clinical testing were similar among undiagnosed coeliac disease and controls (odds ratio (OR) 1.18; 95% CI: 0.85-1.63, P = 0.32). Most individual indications were not associated with serologic status. Exceptions to this include hypothyroidism, which was more likely in cases of undiagnosed coeliac disease, and dyspepsia and chronic diarrhoea, which were less likely. Cases of undiagnosed coeliac disease were more likely to develop osteoporosis (P = 0.005), dermatitis herpetiformis (P = 0.006), chronic fatigue (P = 0.033), thyroiditis (P = 0.003), autoimmune diseases (P = 0.008), and have a family member diagnosed with coeliac disease (P = 0.001). This study strongly suggests that current case finding is not effective in detecting undiagnosed coeliac disease. Individuals with undiagnosed coeliac disease were more likely than controls to develop indications for testing overtime. A more effective method for detection of coeliac disease is needed. © 2018 John Wiley & Sons Ltd and Mayo Foundation.

Systemic Lupus Erythematosus is Associated with Uranium Exposure in a Community Living Near a Uranium Processing Plant: A Nested Case-Control Study

PubMed Central

Lu-Fritts, Pai-Yue; Kottyan, Leah C.; James, Judith A.; Xie, Changchung; Buckholz, Jeanette M.; Pinney, Susan M.; Harley, John B.

2014-01-01

Objective Explore the hypothesis that cases of SLE will be found more frequently in community members with high prior uranium exposure in the Fernald Community Cohort (FCC). Methods A nested case control study was performed. The FCC is a volunteer population that lived near a uranium ore processing plant in Fernald, Ohio, USA during plant operation and members were monitored for 18 years. Uranium plant workers were excluded. SLE cases were identified using American College of Rheumatology classification criteria, laboratory testing, and medical record review. Each case was matched to four age-, race-, and sex-matched controls. Sera from potential cases and controls were screened for autoantibodies. Cumulative uranium particulate exposure was calculated using a dosimetry model. Logistic regression with covariates was used to calculate odds ratios (OR) with 95% confidence intervals (CI). Results The FCC includes 4,187 individuals with background uranium exposure, 1,273 with moderate exposure, and 2,756 with higher exposure. SLE was confirmed in 23 of 31 individuals with a lupus ICD9 code, and in 2 of 43 other individuals prescribed hydroxychloroquine. The female:male ratio was 5.25:1. Of the 25 SLE cases, 12 were in the higher exposure group. SLE was associated with higher uranium exposure (OR 3.92, 95% CI 1.131-13.588, p = 0.031). Conclusion High uranium exposure is associated with SLE relative to matched controls in this sample of uranium exposed individuals. Potential explanations for this relationship include possible autoimmune or estrogen effects of uranium, somatic mutation, epigenetic effects, or effects of some other unidentified accompanying exposure. PMID:25103365

Intrapartum fetal heart rate patterns of trisomy 21 fetuses: A case-control study.

PubMed

Koren, Inbal; Michaelson-Cohen, Rachel; Chen, Daniela; Michaeli, Jennia; Schimmel, Michael; Tsafrir, Avi; Shen, Ori

2016-01-01

To determine whether there are specific characteristic intrapartum heart rate patterns for fetuses with trisomy 21(T21). Intrapartum fetal heart rate (FHR) tracings of T21 fetuses were compared to those of euploid fetuses in a retrospective, observational, matched, case-control study. The study group consisted of 42 fetuses with T21 and 42 matched euploid controls. Matching was designed to accommodate possible confounders. The sign test and McNemar's test were used for categorical variables. The paired t test was used for comparison between quantitative variables. Intrapartum baseline FHR of fetuses with T21 was found to be slightly decreased compared to controls (122.5 vs 129.05 beats per minute, p=0.028). No differences were detected in the presence of periodic changes, or FHR variability between the groups. When evaluating intrapartum FHR of fetuses with T21, decreased baseline FHR can be expected. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

A nested case-control study of fatal work related injuries among Brazilian steel workers.

PubMed Central

Barreto, S M; Swerdlow, A J; Smith, P G; Higgins, C D

1997-01-01

OBJECTIVES: To estimate the relative risk of death from work related injury in a steelworks, associated with exposure to various occupational hazards, sociodemographic factors, and medical history. MATERIAL AND METHODS: The study was a nested case-control design. It was based on a cohort of men employed in the steel plant of USIMINAS, Brazil between January 1977 and August 1990, who were followed up to November 1992. The cases were defined as all workers in the cohort who died from injury in the study period and whose death had been notified to the Brazilian Ministry of Labour as being related to work. Four controls per case, matched to cases on year of birth, were randomly selected from among workers employed in the plant at the time of death of the matching case. Data on potential risk factors for occupational injury were extracted from company records; for the controls these data were abstracted for the period preceding the death of the matching case. RESULTS: There were 37 deaths related to work injuries during the study period. Four surviving workers were selected as controls for each case, but for eight the personnel records were incomplete, leaving 140 controls in all. Significantly increased risk of fatal injury related to work was associated with exposure to noise, heat, dust and fumes, gases and vapours, rotating shift work, being a manual worker, and working in the steel mill, coke ovens, blast furnaces, and energy and water supply areas. Risk of fatal injury related to work increased with intensity of exposure to noise (P (trend) = 0.004) and heat (P < 0.001), and increased greatly with a hazard score that combined information on noise, heat, dust, and gas exposure (P < 0.001). Number of years of schooling (P = 0.03) and salary level (P = 0.03) were both negatively associated with risk. In a multivariate analysis including all these significant factors, only hazard score and area of work remained associated with death from injury related to work. The highest risks were for men exposed to all four environmental hazards (odds ratio (OR) 19.4; 95% confidence interval (95% CI) 1.1 to 352.1) and those working in the energy supply area (OR 18.0; 1.6 to 198.1). CONCLUSIONS: The study identified parts of the steelworks and types of hazard associated with greatly increased risk of fatal accident. Research and measures to prevent accidents need to concentrate on these areas and the people working in them. The use of a hazard score was successful in identifying high risk, and similar scoring might prove useful in other industrial situations. PMID:9326164

Chronic Rhinosinusitis Associated with Erectile Dysfunction: A Population-Based Study.

PubMed

Tai, Shu-Yu; Wang, Ling-Feng; Tai, Chih-Feng; Huang, Yu-Ting; Chien, Chen-Yu

2016-08-31

Few studies have investigated the relationship between chronic rhinosinusitis (CRS) and erectile dysfunction (ED). This case-control study aimed to investigate the association between CRS and the risk of ED in a large national sample. Tapping Taiwan's National Health Insurance Research Database, we identified people 30 years or older with a new primary diagnosis of CRS between 1996 and 2007. The cases were compared with sex- and age-matched controls. We identified 14 039 cases and recruited 140 387 matched controls. Both groups were followed up in the same database until the end of 2007 for instances of ED. Of those with CRS, 294 (2.1%) developed ED during a mean (SD) follow-up of 3.20 (2.33) years, while 1 661 (1.2%) of the matched controls developed ED, mean follow up 2.97 (2.39) years. Cox regression analyses were performed adjusting for sex, age, insurance premium, residence, hypertension, hyperlipidemia, diabetes, obesity, coronary heart disease, chronic kidney disease, chronic obstructive pulmonary disease, asthma, allergic rhinitis, arrhythmia, ischemic stroke, intracerebral hemorrhage, and medications. CRS was revealed to be an independent predictor of ED in the fully adjusted model (HR = 1.51; 95% CI = 1.33-1.73; P < 0.0001).

Effects of a psychosocial intervention on survival among patients with stage I breast and prostate cancer: a matched case-control study.

PubMed

Shrock, D; Palmer, R F; Taylor, B

1999-05-01

Psychosocial factors have been linked to the development and progression of cancer and shown to be relevant in cancer care. However, the evidence that psychosocial interventions affect cancer survival is less conclusive. Few methodologically sound studies have addressed this issue. To investigate the effects of a 6-week psychosocial intervention on survival among patients with stage I breast and prostate cancer. Matched case-control. 3 rural hospitals or cancer centers in central Pennsylvania. 21 breast and 29 prostate stage I cancer patients (treatment group) matched with 74 breast and 65 prostate stage I cancer patients from the same hospitals who did not receive the intervention (control group). Six 2-hour health psychology classes conducted by a licensed staff psychologist. Survival time was compared between the 2 groups and with national norms. The intervention group lived significantly longer than did matched controls. At 4- to 7-year follow-up (median = 4.2 years), none of the breast cancer patients in the intervention group died, whereas 12% of those in the control group died. Twice as many matched-control prostate cancer patients died compared with those in the intervention group (28% vs 14%). Control group survival was similar to national norms. These results are consistent with prior clinical trials and suggest that short-term psychosocial interventions that encourage the expression of emotions, provide social support, and teach coping skills can influence survival among cancer patients. However, self-selection bias cannot be ruled out as an alternative explanation for the results. These interventions merit further consideration and research.

Pulmonary Tuberculosis Is Associated With Biomass Fuel Use Among Rural Women in Pakistan: An Age- and Residence-Matched Case-Control Study.

PubMed

Rabbani, Unaib; Sahito, Ambreen; Nafees, Asaad Ahmed; Kazi, Ambreen; Fatmi, Zafar

2017-04-01

Facility-based, age- and residential area-matched case-control study was conducted in Sindh, Pakistan to determine association between biomass fuel use for cooking and pulmonary tuberculosis (TB). Cases were women with pulmonary TB, and controls were those suffering from other diseases. Current users of biomass fuel were at higher risk of pulmonary TB (adjusted matched odds ratio [mOR] = 3.0; 95% CI = 1.1-4.9) compared with nonusers. In comparison with former biomass users (women not using biomass for >10 years), recent biomass users (women who switched from biomass to nonbiomass ≤10 years ago), and current (lifetime) users were at a higher risk in a dose-response manner (adjusted mOR = 2.8, 95% CI = 0.9-8.2 and adjusted mOR = 3.9, 95% CI = 1.4-10.7, respectively). Population attributable fraction for TB related to biomass fuel use was 40.6% (95% CI = 35.5%-45.7%). This study strengthens the evidence that biomass fuel use for cooking is associated with pulmonary TB and risk increases with duration of exposure.

Factors associated with coronary artery disease and stroke in adults with congenital heart disease.

PubMed

Bokma, Jouke P; Zegstroo, Ineke; Kuijpers, Joey M; Konings, Thelma C; van Kimmenade, Roland R J; van Melle, Joost P; Kiès, Philippine; Mulder, Barbara J M; Bouma, Berto J

2018-04-01

To determine factors associated with coronary artery disease (CAD) and ischaemic stroke in ageing adult congenital heart disease (ACHD) patients. We performed a multicentre case-control study, using data from the national CONgenital CORvitia (CONCOR) registry to identify ACHD patients within five participating centres. Patients with CAD were matched (1:2 ratio) with ACHD patients without CAD on age, CHD defect group and gender. Patients with ischaemic stroke (or transient ischaemic attack) were matched similarly. Medical charts were reviewed and a standardised questionnaire was used to determine presence of risk factors. Of 6904 ACHD patients, a total of 55 cases with CAD (80% male, mean age 55.1±12.4 years) and 56 cases with stroke (46% male, mean age 46.9±15.2) were included and matched with control patients. In multivariable logistic regression analysis, traditional atherosclerotic risk factors (hypertension (OR 2.45; 95% CI 1.15 to 5.23), hypercholesterolaemia (OR 3.99; 95% CI 1.62 to 9.83) and smoking (OR 2.25; 95% CI 1.09 to 4.66)) were associated with CAD. In contrast, these risk factors were not associated with ischaemic stroke. In multivariable analysis, stroke was associated with previous shunt operations (OR 4.20; 95% CI 1.36 to 12.9), residual/unclosed septal defects (OR 2.38; 95% CI 1.03 to 5.51) and left-sided mechanical valves (OR 2.67; 95% CI 1.09 to 6.50). Traditional atherosclerotic risk factors were associated with CAD in ACHD patients. In contrast, ischaemic stroke was related to factors (previous shunts, septal defects, mechanical valves) suggesting a cardioembolic aetiology. These findings may inform surveillance and prevention strategies. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Pituitary gland volumes in bipolar disorder.

PubMed

Clark, Ian A; Mackay, Clare E; Goodwin, Guy M

2014-12-01

Bipolar disorder has been associated with increased Hypothalamic-Pituitary-Adrenal axis function. The mechanism is not well understood, but there may be associated increases in pituitary gland volume (PGV) and these small increases may be functionally significant. However, research investigating PGV in bipolar disorder reports mixed results. The aim of the current study was twofold. First, to assess PGV in two novel samples of patients with bipolar disorder and matched healthy controls. Second, to perform a meta-analysis comparing PGV across a larger sample of patients and matched controls. Sample 1 consisted of 23 established patients and 32 matched controls. Sample 2 consisted of 39 medication-naïve patients and 42 matched controls. PGV was measured on structural MRI scans. Seven further studies were identified comparing PGV between patients and matched controls (total n; 244 patients, 308 controls). Both novel samples showed a small (approximately 20mm(3) or 4%), but non-significant, increase in PGV in patients. Combining the two novel samples showed a significant association of age and PGV. Meta-analysis showed a trend towards a larger pituitary gland in patients (effect size: .23, CI: -.14, .59). While results suggest a possible small difference in pituitary gland volume between patients and matched controls, larger mega-analyses with sample sizes greater even than those used in the current meta-analysis are still required. There is a small but potentially functionally significant increase in PGV in patients with bipolar disorder compared to controls. Results demonstrate the difficulty of finding potentially important but small effects in functional brain disorders. Copyright © 2014 Elsevier B.V. All rights reserved.

UV-laser microdissection and mRNA expression analysis of individual neurons from postmortem Parkinson's disease brains.

PubMed

Gründemann, Jan; Schlaudraff, Falk; Liss, Birgit

2011-01-01

Cell specificity of gene expression analysis is essential to avoid tissue sample related artifacts, in particular when the relative number of target cells present in the compared tissues varies dramatically, e.g., when comparing dopamine neurons in midbrain tissues from control subjects with those from Parkinson's disease (PD) cases. Here, we describe a detailed protocol that combines contact-free UV-laser microdissection and quantitative PCR of reverse-transcribed RNA of individual neurons from postmortem human midbrain tissue from PD patients and unaffected controls. Among expression changes in a variety of dopamine neuron marker, maintenance, and cell-metabolism genes, we found that α-synuclein mRNA levels were significantly elevated in individual neuromelanin-positive dopamine midbrain neurons from PD brains when compared to those from matched controls.

Outbreak of Shiga Toxin-Producing Escherichia coli (STEC) O157:H7 Associated with Romaine Lettuce Consumption, 2011

PubMed Central

Slayton, Rachel B.; Turabelidze, George; Bennett, Sarah D.; Schwensohn, Colin A.; Yaffee, Anna Q.; Khan, Faisal; Butler, Cindy; Trees, Eija; Ayers, Tracy L.; Davis, Marjorie L.; Laufer, Alison S.; Gladbach, Stephen; Williams, Ian; Gieraltowski, Laura B.

2013-01-01

Background Shiga toxin-producing Escherichia coli (STEC) O157:H7 is the causal agent for more than 96,000 cases of diarrheal illness and 3,200 infection-attributable hospitalizations annually in the United States. Materials and Methods We defined a confirmed case as a compatible illness in a person with the outbreak strain during 10/07/2011-11/30/2011. Investigation included hypothesis generation, a case-control study utilizing geographically-matched controls, and a case series investigation. Environmental inspections and tracebacks were conducted. Results We identified 58 cases in 10 states; 67% were hospitalized and 6.4% developed hemolytic uremic syndrome. Any romaine consumption was significantly associated with illness (matched Odds Ratio (mOR) = 10.0, 95% Confidence Interval (CI) = 2.1–97.0). Grocery Store Chain A salad bar was significantly associated with illness (mOR = 18.9, 95% CI = 4.5–176.8). Two separate traceback investigations for romaine lettuce converged on Farm A. Case series results indicate that cases (64.9%) were more likely than the FoodNet population (47%) to eat romaine lettuce (p-value = 0.013); 61.3% of cases reported consuming romaine lettuce from the Grocery Store Chain A salad bar. Conclusions This multistate outbreak of STEC O157:H7 infections was associated with consumption of romaine lettuce. Traceback analysis determined that a single common lot of romaine lettuce harvested from Farm A was used to supply Grocery Store Chain A and a university campus linked to a case with the outbreak strain. An investigation at Farm A did not identify the source of contamination. Improved ability to trace produce from the growing fields to the point of consumption will allow more timely prevention and control measures to be implemented. PMID:23390525

Hyperactivity of the default-mode network in first-episode, drug-naive schizophrenia at rest revealed by family-based case-control and traditional case-control designs.

PubMed

Guo, Wenbin; Liu, Feng; Chen, Jindong; Wu, Renrong; Li, Lehua; Zhang, Zhikun; Chen, Huafu; Zhao, Jingping

2017-03-01

Abnormal regional activity and functional connectivity of the default-mode network (DMN) have been reported in schizophrenia. However, previous studies may have been biased by unmatched case-control design. To limit such bias, the present study used both the family-based case-control design and the traditional case-control design to investigate abnormal regional activity of the DMN in patients with schizophrenia at rest.Twenty-eight first-episode, drug-naive patients with schizophrenia, 28 age-, sex-matched unaffected siblings of the patients (family-based controls, FBC), and 40 healthy controls (HC) underwent resting-state functional magnetic resonance imaging (fMRI) scans. The group-independent component analysis and fractional amplitude of low-frequency fluctuation (fALFF) methods were used to analyze the data.Patients with schizophrenia show increased fALFF in an overlapped region of the right superior medial prefrontal cortex (MPFC) relative to the FBC and the HC. Compared with the HC, the patients and the FBC exhibit increased fALFF in an overlapped region of the left posterior cingulate cortex/precuneus (PCC/PCu). Furthermore, the z values of the 2 overlapped regions can separate the patients from the FBC/HC, and separate the patients/FBC from the HC with relatively high sensitivity and specificity.Both the family-based case-control and traditional case-control designs reveal hyperactivity of the DMN in first-episode, drug-naive patients with paranoid schizophrenia, which highlights the importance of the DMN in the neurobiology of schizophrenia. Family-based case-control design can limit the confounding effects of environmental factors in schizophrenia. Combination of the family-based case-control and traditional case-control designs may be a viable option for the neuroimaging studies.

Melasma and its association with different types of nevi in women: A case-control study

PubMed Central

Adalatkhah, Hassan; Sadeghi-bazargani, Homayoun; Amini-sani, Nayereh; Zeynizadeh, Somayeh

2008-01-01

Background Very little is known about possible association of nevi and melasma. The study objective was to determine if there is an association between melasma and existence of different kinds of nevi. Methods In a case-control study, 120 female melasma patients referred to dermatology clinic of Ardabil and 120 patients referred to other specialty clinics who lacked melasma were enrolled after matching for age. Number of different types of nevi including lentigines and melanocytic nevi were compared between case and control group patients. Data were entered into the computer and analyzed by SPSS 13 statistical software. Results Mean number of lentigines was 25.5 in melasma group compared to 8 in control group(P < 0.01). Mean number of melanocytic nevi was 13.2 in cases compared to 2.8 in control group(P < 0.001). Multivariate analysis showed that existence of freckles, lentigines and more than three melanocytic nevi were positively related to developing melasma. The chance of melasma increased up to 23 times for patients having more than three melanocytic nevi. Congenital nevi were observed among 10% both in case and control groups. Campbell de morgan angiomas were seen among 26 patients(21.8%) in case group compared to 6 patients(5%) in control group. Conclusion Existence of lentigines and melanocytic nevi increases chance of having melasma PMID:18680608

Allergies and Risk of Head and Neck Cancer: An Original Study plus Meta-Analysis

PubMed Central

Lo, Hung-I; Huang, Cheng-Chih; Lee, Wei-Ting; Huang, Jehn-Shyun; Chen, Ken-Chung; Wong, Tung-Yiu; Tsai, Sen-Tien; Yen, Chia-Jui; Wu, Yuan-Hua; Hsueh, Wei-Ting; Yang, Ming-Wei; Wu, Shang-Yin; Chang, Jang-Yang; Chang, Kwang-Yu; Lin, Chen-Lin; Wang, Fang-Ting; Wang, Yi-Hui; Weng, Ya-Ling; Yang, Han-Chien; Chang, Jeffrey S.

2013-01-01

Background Although the relationship between allergy and cancer has been investigated extensively, the role of allergy in head and neck cancer (HNC) appears less consistent. It is not clear whether allergies can independently influence the risk of HNC in the presence of known strong environmental risk factors, including consumption of alcohol, betel quid, and cigarette. Methods The current paper reports results from: 1) an original hospital-based case-control study, which included 252 incident cases of HNC and 236 controls frequency-matched to cases on sex and age; and 2) a meta-analysis combining the results of the current case-control study and 13 previously published studies (9 cohort studies with 727,569 subjects and 550 HNC outcomes and 5 case-control studies with 4,017 HNC cases and 10,928 controls). Results In the original case-control study, we observed a strong inverse association between allergies and HNC [odds ratio = 0.41, 95% confidence interval (CI): 0.27–0.62]. The meta-analysis also indicated a statistically significant inverse association between HNC and allergies [meta-relative risk (RR) = 0.76, 95% CI: 0.63–0.91], particularly strong for allergic rhinitis (meta-RR = 0.55, 95% CI: 0.40–0.76). In addition, the inverse association between allergies and HNC was observed only among men (meta-RR = 0.67, 95% CI: 0.54–0.84) but not among women (meta-RR = 0.98, 95% CI: 0.81–1.18). Conclusions These findings suggest that immunity plays an influential role in the risk of HNC. Future studies investigating immune biomarkers, including cytokine profiles and genetic polymorphisms, are warranted to further delineate the relationship between allergies and HNC. Understanding the relationship between allergies and HNC may help devise effective strategies to reduce and treat HNC. PMID:23383309

Human-Automation Integration: Principle and Method for Design and Evaluation

NASA Technical Reports Server (NTRS)

Billman, Dorrit; Feary, Michael

2012-01-01

Future space missions will increasingly depend on integration of complex engineered systems with their human operators. It is important to ensure that the systems that are designed and developed do a good job of supporting the needs of the work domain. Our research investigates methods for needs analysis. We included analysis of work products (plans for regulation of the space station) as well as work processes (tasks using current software), in a case study of Attitude Determination and Control Officers (ADCO) planning work. This allows comparing how well different designs match the structure of the work to be supported. Redesigned planning software that better matches the structure of work was developed and experimentally assessed. The new prototype enabled substantially faster and more accurate performance in plan revision tasks. This success suggests the approach to needs assessment and use in design and evaluation is promising, and merits investigatation in future research.

Impact of treatment with pioglitazone on stroke outcomes: a real world database analysis.

PubMed

Morgan, Christopher Ll; Inzucchi, Silvio E; Puelles, Jorge; Jenkins-Jones, Sara; Currie, Craig J

2018-05-07

Randomised controlled trials have reported an association between pioglitazone and reduced incidence of stroke in type 2 diabetic (T2DM) and insulin-resistant populations. We investigated this association within a real-world database. T2DM patients initiating pioglitazone between 2000-2012 were extracted from the Clinical Practice Research Datalink (CPRD); a UK routine. Two non-exposed control cohorts were matched on age, gender, HbA1c, diabetes duration, stroke history, co-morbidities and prior T2DM regimen. Control cohort-1 comprised patients initiating a new T2DM therapy as their respective case initiated pioglitazone. Control cohort-2 remained on the same T2DM regimen as their respective case prior to the case initiating pioglitazone. The primary outcome was incident stroke; other outcomes included mortality, hospital length of stay and stroke recurrence. 4,234 pioglitazone patients matched to controls in cohort-1 and 3,604 in cohort-2. For the primary outcome there were significantly reduced hazard ratios (HRs) for cases:controls. Cohort 1, the HR was 0.627 (95% CI, 0.404-0.972) during the therapy period and 0.640 (0.485-0.843) over the entire observation period; respective HRs were 0.516 (0.336-0.794) and 0.773 (0.611-0.978) for cohort 2. There was no significant difference in 30-day mortality rate or rate of recurrent stroke. For hospitalised stroke events there was a significant difference in length of stay for patients discharged to usual residence (median 3.0 days versus 7.0 days; p=0.008) for control cohort-2 whilst on-treatment. In support of evidence from two large randomized trials, these observational data show that pioglitazone has a potent effect in reducing stroke events in patients with type 2 diabetes. This article is protected by copyright. All rights reserved.

Household and Individual Risk Factors for Cholera among Cholera Vaccine Recipients in Rural Haiti

PubMed Central

Matias, Wilfredo R.; Teng, Jessica E.; Hilaire, Isabelle J.; Harris, Jason B.; Franke, Molly F.; Ivers, Louise C.

2017-01-01

Abstract. Oral cholera vaccination was used as part of cholera control in Haiti, but the vaccine does not provide complete protection. We conducted secondary data analyses of a vaccine effectiveness study in Haiti to evaluate risk factors for cholera among cholera vaccine recipients. Individuals vaccinated against cholera that presented with acute watery diarrhea and had a stool sample positive for Vibrio cholerae O1 were included as cases. Up to four vaccinated individuals who did not present for treatment of diarrhea were included as controls for each case, and matched by location of residence, enrollment time, and age. We evaluated sociodemographic characteristics and risk factors for cholera. Univariable and multivariable logistic regression were performed to identify risk factors for cholera among vaccinees. Thirty-three vaccine recipients with culture-confirmed cholera were included as cases. One-hundred-and-seventeen of their matched controls reported receiving vaccine and were included as controls. In a multivariable analysis, self-reporting use of branded household water disinfection products as a means of treating water (adjusted relative risk [aRR] = 44.3, 95% confidence interval [CI] = 4.19–468.05, P = 0.002), and reporting having a latrine as the main household toilet (aRR = 4.22, 95% CI = 1.23–14.43, P = 0.02), were independent risk factors for cholera. Self-reporting always treating water (aRR = 0.09, 95% CI = 0.01–0.57, P = 0.01) was associated with protection against cholera. The field effectiveness of water, sanitation, and hygiene interventions used in combination with cholera vaccination in cholera control should be measured and monitored over time to identify and remediate shortcomings, and ensure successful impact on disease control. PMID:28722575

A Comparative Study of Pituitary Volume Variations in MRI in Acute Onset of Psychiatric Conditions.

PubMed

Soni, Brijesh Kumar; Joish, Upendra Kumar; Sahni, Hirdesh; George, Raju A; Sivasankar, Rajeev; Aggarwal, Rohit

2017-02-01

The growing belief that endocrine abnormalities may underlie many mental conditions has led to increased use of imaging and hormonal assays in patients attending to psychiatric OPDs. People who are in an acute phase of a psychiatric disorder show Hypothalamic Pituitary Adrenal (HPA) axis hyperactivity, but the precise underlying central mechanisms are unclear. To assess the pituitary gland volume variations in patients presenting with new onset acute psychiatric illness in comparison with age and gender matched controls by using MRI. The study included 50 patients, with symptoms of acute psychiatric illness presenting within one month of onset of illness and 50 age and gender matched healthy controls. Both patients and controls were made to undergo MRI of the Brain. A 0.9 mm slices of entire brain were obtained by 3 dimensional T1 weighted sequence. Pituitary gland was traced in all sagittal slices. Anterior pituitary and posterior pituitary bright spot were measured separately in each slice. Volume of the pituitary (in cubic centimetre- cm 3 ) was calculated by summing areas. Significance of variations in pituitary gland volumes was compared between the cases and controls using Analysis of Covariance (ANOVA). There were significantly larger pituitary gland volumes in the cases than the controls, irrespective of psychiatric diagnosis (ANOVA, f=15.56; p=0.0002). Pituitary volumes in cases were 15.36% (0.73 cm 3 ) higher than in controls. There is a strong likelihood of HPA axis overactivity during initial phase of all mental disorders along with increased pituitary gland volumes. Further studies including hormonal assays and correlation with imaging are likely to provide further insight into neuroanatomical and pathological basis of psychiatric disorders.

Household and Individual Risk Factors for Cholera among Cholera Vaccine Recipients in Rural Haiti.

PubMed

Matias, Wilfredo R; Teng, Jessica E; Hilaire, Isabelle J; Harris, Jason B; Franke, Molly F; Ivers, Louise C

2017-08-01

Oral cholera vaccination was used as part of cholera control in Haiti, but the vaccine does not provide complete protection. We conducted secondary data analyses of a vaccine effectiveness study in Haiti to evaluate risk factors for cholera among cholera vaccine recipients. Individuals vaccinated against cholera that presented with acute watery diarrhea and had a stool sample positive for Vibrio cholerae O1 were included as cases. Up to four vaccinated individuals who did not present for treatment of diarrhea were included as controls for each case, and matched by location of residence, enrollment time, and age. We evaluated sociodemographic characteristics and risk factors for cholera. Univariable and multivariable logistic regression were performed to identify risk factors for cholera among vaccinees. Thirty-three vaccine recipients with culture-confirmed cholera were included as cases. One-hundred-and-seventeen of their matched controls reported receiving vaccine and were included as controls. In a multivariable analysis, self-reporting use of branded household water disinfection products as a means of treating water (adjusted relative risk [aRR] = 44.3, 95% confidence interval [CI] = 4.19-468.05, P = 0.002), and reporting having a latrine as the main household toilet (aRR = 4.22, 95% CI = 1.23-14.43, P = 0.02), were independent risk factors for cholera. Self-reporting always treating water (aRR = 0.09, 95% CI = 0.01-0.57, P = 0.01) was associated with protection against cholera. The field effectiveness of water, sanitation, and hygiene interventions used in combination with cholera vaccination in cholera control should be measured and monitored over time to identify and remediate shortcomings, and ensure successful impact on disease control.

The Use of Benzodiazepine Receptor Agonists and Risk of Respiratory Failure in Patients with Chronic Obstructive Pulmonary Disease: A Nationwide Population-Based Case-Control Study.

PubMed

Chen, Su-Jung; Yeh, Chiu-Mei; Chao, Tze-Fan; Liu, Chia-Jen; Wang, Kang-Ling; Chen, Tzeng-Ji; Chou, Pesus; Wang, Fu-Der

2015-07-01

Insomnia is prevalent in patients with chronic obstructive pulmonary disease (COPD), and benzodiazepine receptor agonists (BZRAs) are the most commonly used drugs despite their adverse effects on respiratory function. The aim of this study was to investigate whether the use of BZRAs was associated with an increased risk of respiratory failure (RF) in COPD patients. Matched case-control study. National Health Insurance Research Database (NHIRD) in Taiwan. The case group consisted of 2,434 COPD patients with RF, and the control group consisted of 2,434 COPD patients without RF, matched for age, sex, and date of enrollment. Exposure to BZRAs during the 180-day period preceding the index date was analyzed and compared in the case and control groups. Conditional logistic regression was performed, and the use of BZRAs was associated with an increased risk of RF (adjusted odds ratio [aOR] 1.56, 95% confidence interval [CI] 1.14-2.13). In subgroup analysis, we found that the benzodiazepine (BZD) users had a higher risk of RF (aOR 1.58, 95% CI 1.14-2.20), whereas the risk in non-benzodiazepine (non-BZD) users was insignificant (aOR 0.85, 95% CI 0.51-1.44). A greater than 2-fold increase in risk was found in those who received two or more kinds of BZRAs and those using a combination of BZD and non-BZD medications. The use of benzodiazepine receptor agonists was a significant risk factor for respiratory failure in patients with chronic obstructive pulmonary disease (COPD). Compared to benzodiazepine, the prescription of non-benzodiazepine may be safer for the management of insomnia in COPD patients. © 2015 Associated Professional Sleep Societies, LLC.

A close examination of healthcare expenditures related to fractures.

PubMed

Kilgore, Meredith L; Curtis, Jeffrey R; Delzell, Elizabeth; Becker, David J; Arora, Tarun; Saag, Kenneth G; Morrisey, Michael A

2013-04-01

This study evaluated reasons for healthcare expenditures both before and after the occurrence of fractures among Medicare beneficiaries. In a previous study we examined healthcare expenditures in the 6 months before and after fractures. The difference-"incremental" expenditures-provides one estimate of the potentially avoidable costs associated with fractures. We constructed a second estimate of the cost burden-"attributable" expenditures-using only those costs recorded in claims with fracture diagnosis codes. Attributable expenditures accounted for only 24% to 60% of incremental expenditures, depending on the fracture site. We examined health care expenditures between 1999 and 2005 among Medicare beneficiaries who experienced fractures (cases) and among beneficiaries who did not experience fractures (controls), matched to cases on age, race, and sex. We also examined healthcare expenditures for cases and controls for 24 months prior to the fracture index date. When expenditures associated with diagnoses for aftercare, joint pain, and osteoporosis, other musculoskeletal diagnoses, pneumonia, and pressure ulcers were included, the proportion of incremental costs directly attributable to fracture care rose to 72% to 88%. Expenditures prior to fracture were higher for cases than controls, and the rate of increase accelerated over the 12 months prior to the hip fracture. Our findings confirm that the original incremental cost analysis constituted a satisfactory method for estimating avoidable costs associated with fractures. We also conclude that those with fractures had much higher and growing healthcare expenditures in the 12 months prior to the event, compared with age-, race-, and sex-matched controls. This suggests that patterns of healthcare services utilization may provide a means to improve fracture prediction rules. Copyright © 2013 American Society for Bone and Mineral Research.

Geographic Region, Weather, Pilot Age and Air Carrier Crashes: a Case-Control Study

PubMed Central

Li, Guohua; Pressley, Joyce C.; Qiang, Yandong; Grabowski, Jurek G.; Baker, Susan P.; Rebok, George W.

2009-01-01

Background Information about risk factors of aviation crashes is crucial for developing effective intervention programs. Previous studies assessing factors associated with crash risk were conducted primarily in general aviation, air taxis and commuter air carriers. Methods A matched case-control design was used to examine the associations of geographic region, basic weather condition, and pilot age with the risk of air carrier (14 CFR Part 121) crash involvement. Cases (n=373) were air carrier crashes involving aircraft made by Boeing, McDonnell Douglas, and Airbus, recorded in the National Transportation Safety Board’s aviation crash database during 1983 through 2002, and controls (n=746) were air carrier incidents involving aircraft of the same three makes selected at random from the Federal Aviation Administration’s aviation incident database. Each case was matched with two controls on the calendar year when the index crash occurred. Conditional logistic regression was used for statistical analysis. Results With adjustment for basic weather condition, pilot age, and total flight time, the risk of air carrier crashes in Alaska was more than three times the risk for other regions [adjusted odds ratio (OR) 3.18, 95% confidence interval (CI) 1.35 – 7.49]. Instrument meteorological conditions were associated with an increased risk for air carrier crashes involving pilot error (adjusted OR 2.26, 95% CI 1.15 – 4.44) and a decreased risk for air carrier crashes without pilot error (adjusted OR 0.57, 95% CI 0.40 – 0.87). Neither pilot age nor total flight time was significantly associated with the risk of air carrier crashes. Conclusions The excess risk of air carrier crashes in Alaska and the effect of adverse weather on pilot-error crashes underscore the importance of environmental hazards in flight safety. PMID:19378910

Geographic region, weather, pilot age, and air carrier crashes: a case-control study.

PubMed

Li, Guohua; Pressley, Joyce C; Qiang, Yandong; Grabowski, Jurek G; Baker, Susan P; Rebok, George W

2009-04-01

Information about risk factors of aviation crashes is crucial for developing effective intervention programs. Previous studies assessing factors associated with crash risk were conducted primarily in general aviation, air taxis, and commuter air carriers. A matched case-control design was used to examine the associations of geographic region, basic weather condition, and pilot age with the risk of air carrier (14 CFR Part 121) crash involvement. Cases (N = 373) were air carrier crashes involving aircraft made by Boeing, McDonnell Douglas, and Airbus recorded in the National Transportation Safety Board's aviation crash database during 1983 through 2002, and controls (N = 746) were air carrier incidents involving aircraft of the same three makes selected at random from the Federal Aviation Administration's aviation incident database. Each case was matched with two controls on the calendar year when the index crash occurred. Conditional logistic regression was used for statistical analysis. With adjustment for basic weather condition, pilot age, and total flight time, the risk of air carrier crashes in Alaska was more than three times the risk for other regions ladjusted odds ratio (OR) 3.18, 95% confidence interval (CI) 1.35-7.49]. Instrument meteorological conditions were associated with an increased risk for air carrier crashes involving pilot error (adjusted OR 2.26, 95% CI 1.15-4.44) and a decreased risk for air carrier crashes without pilot error (adjusted OR 0.60, 95% CI 0.37-0.96). Neither pilot age nor total flight time were significantly associated with the risk of air carrier crashes. The excess risk of air carrier crashes in Alaska and the effect of adverse weather on pilot-error crashes underscore the importance of environmental hazards in flight safety.

Proton pump inhibitor and histamine-2 receptor antagonist use and risk of liver cancer in two population-based studies.

PubMed

Tran, K T; McMenamin, Ú C; Hicks, B; Murchie, P; Thrift, A P; Coleman, H G; Iversen, L; Johnston, B T; Lee, A J; Cardwell, C R

2018-05-09

Proton pump inhibitors (PPIs) and histamine-2 receptor antagonists (H2RAs) are commonly used. PPIs have been shown to promote liver cancer in rats; however, only one study has examined the association in humans. To investigate PPIs and H2RAs and risk of primary liver cancer in two large independent study populations. We conducted a nested case-control study within the Primary Care Clinical Informatics Unit (PCCIU) database in which up to five controls were matched to cases with primary liver cancer, recorded by General Practitioners. Odds ratios (ORs) and 95% confidence intervals (95% CIs) for associations with prescribed PPIs and H2RAs were calculated using conditional logistic regression. We also conducted a prospective cohort study within the UK Biobank using self-reported medication use and cancer-registry recorded primary liver cancer. Hazard ratios (HRs) and 95% CIs were calculated using Cox regression. In the PCCIU case-control analysis, 434 liver cancer cases were matched to 2103 controls. In the UK Biobank cohort, 182 of 475 768 participants developed liver cancer. In both, ever use of PPIs was associated with increased liver cancer risk (adjusted OR 1.80, 95% CI 1.34, 2.41 and adjusted HR 1.99, 95% CI 1.34, 2.94 respectively). There was little evidence of association with H2RA use (adjusted OR 1.21, 95% CI 0.84, 1.76 and adjusted HR 1.70, 95% CI 0.82, 3.53 respectively). We found some evidence that PPI use was associated with liver cancer. Whether this association is causal or reflects residual confounding or reverse causation requires additional research. © 2018 John Wiley & Sons Ltd.

Effectiveness of reactive oral cholera vaccination in rural Haiti: a case-control study and bias-indicator analysis.

PubMed

Ivers, Louise C; Hilaire, Isabelle J; Teng, Jessica E; Almazor, Charles P; Jerome, J Gregory; Ternier, Ralph; Boncy, Jacques; Buteau, Josiane; Murray, Megan B; Harris, Jason B; Franke, Molly F

2015-03-01

Between April and June, 2012, a reactive cholera vaccination campaign was done in Haiti with an oral inactivated bivalent whole-cell vaccine. We aimed to assess the effectiveness of the vaccine in a case-control study and to assess the likelihood of bias in that study in a bias-indicator study. Residents of Bocozel or Grand Saline who were eligible for the vaccination campaign (ie, age ≥12 months, not pregnant, and living in the region at the time of the vaccine campaign) were included. In the primary case-control study, cases had acute watery diarrhoea, sought treatment at one of three participating cholera treatment units, and had a stool sample positive for cholera by culture. For each case, four control individuals who did not seek treatment for acute watery diarrhoea were matched by location of residence, enrolment time (within 2 weeks of the case), and age (1-4 years, 5-15 years, and >15 years). Cases in the bias-indicator study were individuals with acute watery diarrhoea with a negative stool sample for cholera. Controls were selected in the same manner as in the primary case-control study. Trained staff used standard laboratory procedures to do rapid tests and stool cultures from study cases. Participants were interviewed to collect data on sociodemographic characteristics, risk factors for cholera, and self-reported vaccination. Data were analysed by conditional logistic regression, adjusting for matching factors. From Oct 24, 2012, to March 9, 2014, 114 eligible individuals presented with acute watery diarrhoea and were enrolled, 25 of whom were subsequently excluded. 47 participants were analysed as cases in the vaccine effectiveness case-control study and 42 as cases in the bias-indicator study. 33 (70%) of 47 cholera cases self-reported vaccination versus 167 (89%) of 188 controls (vaccine effectiveness 63%, 95% CI 8-85). 27 (57%) of 47 cases had certified vaccination versus 147 (78%) of 188 controls (vaccine effectiveness 58%, 13-80). Neither self-reported nor verified vaccination was significantly associated with non-cholera diarrhoea (vaccine effectiveness 18%, 95% CI -208 to 78 by self-report and -21%, -238 to 57 by verified vaccination). Bivalent whole-cell oral cholera vaccine effectively protected against cholera in Haiti from 4 months to 24 months after vaccination. Vaccination is an important component of efforts to control cholera epidemics. National Institutes of Health, Delivering Oral Vaccines Effectively project, and Department of Global Health and Social Medicine at Harvard Medical School. Copyright © 2015 Ivers et al. Open Access article distributed under the terms of CC BY-NC-ND. Published by .. All rights reserved.

Analysis of Risk Factors for Colonic Diverticular Bleeding: A Matched Case-Control Study.

PubMed

Sugihara, Yuusaku; Kudo, Shin-ei; Miyachi, Hideyuki; Misawa, Masashi; Okoshi, Shogo; Okada, Hiroyuki; Yamamoto, Kazuhide

2016-03-01

Diverticular bleeding can occasionally cause massive bleeding that requires urgent colonoscopy (CS) and treatment. The aim of this study was to identify significant risk factors for colonic diverticular hemorrhage. Between January 2009 and December 2012, 26,602 patients underwent CS at our institution. One hundred twenty-three patients underwent an urgent CS due to acute lower gastrointestinal hemorrhage. Seventy-two patients were diagnosed with colonic diverticular hemorrhage. One hundred forty-nine age- and sex-matched controls were selected from the patients with nonbleeding diverticula who underwent CS during the same period. The relationship of risk factors to diverticular bleeding was compared between the cases and controls. Uni- and multivariate conditional logistic regression analyses demonstrated that the use of nonsteroidal anti-inflammatory drugs (odds ratio [OR], 14.70; 95% confidence interval [CI], 3.89 to 55.80; p<0.0001), as well as the presence of cerebrovascular disease (OR, 8.66; 95% CI, 2.33 to 32.10; p=0.00126), and hyperuricemia (OR, 15.5; 95% CI, 1.74 to 138.00; p=0.014) remained statistically significant predictors of diverticular bleeding. Nonsteroidal anti-inflammatory drugs, cerebrovascular disease and hyperuricemia were significant risks for colonic diverticular hemorrhage. The knowledge obtained from this study may provide some insight into the diagnostic process for patients with lower gastrointestinal bleeding.

Propositional density and cognitive function in later life: findings from the Precursors Study.

PubMed

Engelman, Michal; Agree, Emily M; Meoni, Lucy A; Klag, Michael J

2010-11-01

We used longitudinal data from the Johns Hopkins Precursors Study to test the hypothesis that written propositional density measured early in life is lower for people who develop dementia categorized as Alzheimer's disease (AD). This association was reported in 1996 for the Nun Study, and the Precursors Study offered an unprecedented chance to reexamine it among respondents with different gender, education, and occupation profiles. Eighteen individuals classified as AD patients (average age at diagnosis: 74) were assigned 2 sex-and-age matched controls, and propositional density in medical school admission essays (average age at writing: 22) was assessed via Computerized Propositional Idea Density Rater 3 linguistic analysis software. Adjusted odds ratios (ORs) for the matched case-control study were calculated using conditional (fixed-effects) logistic regression. Mean propositional density is lower for cases than for controls (4.70 vs. 4.99 propositions per 10 words, 1-sided p = .01). Higher propositional density substantially lowers the odds of AD (OR = 0.16, 95% confidence interval = 0.03-0.90, 1-sided p = .02). Propositional density scores in writing samples from early adulthood appear to predict AD in later life for men as well as women. Studies of cognition across the life course might beneficially incorporate propositional density as a potential marker of cognitive reserve.

Reduced Risk of Barrett's Esophagus in Statin Users: Case-Control Study and Meta-Analysis.

PubMed

Beales, Ian L P; Dearman, Leanne; Vardi, Inna; Loke, Yoon

2016-01-01

Use of statins has been associated with a reduced incidence of esophageal adenocarcinoma in population-based studies. However there are few studies examining statin use and the development of Barrett's esophagus. The purpose of this study was to examine the association between statin use and the presence of Barrett's esophagus in patients having their first gastroscopy. We have performed a case-control study comparing statin use between patients with, and without, an incident diagnosis of non-dysplastic Barrett's esophagus. Male Barrett's cases (134) were compared to 268 male age-matched controls in each of two control groups (erosive gastro-esophageal reflux and dyspepsia without significant upper gastrointestinal disease). Risk factor and drug exposure were established using standardised interviews. Logistic regression was used to compare statin exposure and correct for confounding factors. We performed a meta-analysis pooling our results with three other case-control studies. Regular statin use was associated with a significantly lower incidence of Barrett's esophagus compared to the combined control groups [adjusted OR 0.62 (95 % confidence intervals 0.37-0.93)]. This effect was more marked in combined statin plus aspirin users [adjusted OR 0.43 (95 % CI 0.21-0.89)]. The inverse association between statin or statin plus aspirin use and risk of Barrett's was significantly greater with longer duration of use. Meta-analysis of pooled data (1098 Barrett's, 2085 controls) showed that statin use was significantly associated with a reduced risk of Barrett's esophagus [pooled adjusted OR 0.63 (95 % CI 0.51-0.77)]. Statin use is associated with a reduced incidence of a new diagnosis of Barrett's esophagus.

Advance Care Planning in an Accountable Care Organization Is Associated with Increased Advanced Directive Documentation and Decreased Costs

PubMed Central

Kim, Minchul; Franciskovich, Chris M.; Weinberg, Jason E.; Svendsen, Jessica D.; Fehr, Linda S.; Funk, Amy; Sawicki, Robert; Asche, Carl V.

2018-01-01

Abstract Background: Advance care planning (ACP) documents patient wishes and increases awareness of palliative care options. Objective: To study the association of outpatient ACP with advanced directive documentation, utilization, and costs of care. Design: This was a case–control study of cases with ACP who died matched 1:1 with controls. We used 12 months of data pre-ACP/prematch and predeath. We compared rates of documentation with logit model regression and conducted a difference-in-difference analysis using generalized linear models for utilization and costs. Setting/subjects: Medicare beneficiaries attributed to a large rural-suburban-small metro multisite accountable care organization from January 2013 to April 2016, with cross reference to ACP facilitator logs to find cases. Measurements: The presence of advance directive forms was verified by chart review. Cost analysis included all utilization and costs billed to Medicare. Results: We matched 325 cases and 325 controls (51.1% female and 48.9% male, mean age 81). 320/325 (98.5%) ACP versus 243/325 (74.8%) of controls had a Healthcare Power of Attorney (odds ratio [OR] 21.6, 95% CI 8.6–54.1) and 172/325(52.9%) ACP versus 145/325 (44.6%) controls had Practitioner Orders for Life Sustaining Treatment (OR 1.40, 95% CI 1.02–1.90) post-ACP/postmatch. Adjusted results showed ACP cases had fewer inpatient admissions (−0.37 admissions, 95% CI −0.66 to −0.08), and inpatient days (−3.66 days, 95% CI −6.23 to −1.09), with no differences in hospice, hospice days, skilled nursing facility use, home health use, 30-day readmissions, or emergency department visits. Adjusted costs were $9,500 lower in the ACP group (95% CI −$16,207 to −$2,793). Conclusions: ACP increases documentation and was associated with a reduction in overall costs driven primarily by a reduction in inpatient utilization. Our data set was limited by small numbers of minorities and cancer patients. PMID:29206564

Low α-defensin gene copy number increases the risk for IgA nephropathy and renal dysfunction.

PubMed

Ai, Zhen; Li, Ming; Liu, Wenting; Foo, Jia-Nee; Mansouri, Omniah; Yin, Peiran; Zhou, Qian; Tang, Xueqing; Dong, Xiuqing; Feng, Shaozhen; Xu, Ricong; Zhong, Zhong; Chen, Jian; Wan, Jianxin; Lou, Tanqi; Yu, Jianwen; Zhou, Qin; Fan, Jinjin; Mao, Haiping; Gale, Daniel; Barratt, Jonathan; Armour, John A L; Liu, Jianjun; Yu, Xueqing

2016-06-29

Although a major source of genetic variation, copy number variations (CNVs) and their involvement in disease development have not been well studied. Immunoglobulin A nephropathy (IgAN) is the most common primary glomerulonephritis worldwide. We performed association analysis of the DEFA1A3 CNV locus in two independent IgAN cohorts of southern Chinese Han (total of 1189 cases and 1187 controls). We discovered three independent copy number associations within the locus: DEFA1A3 [P = 3.99 × 10(-9); odds ratio (OR), 0.88], DEFA3 (P = 6.55 × 10(-5); OR, 0.82), and a noncoding deletion variant (211bp) (P = 3.50 × 10(-16); OR, 0.75) (OR per copy, fixed-effects meta-analysis). While showing strong association with an increased risk for IgAN (P = 9.56 × 10(-20)), low total copy numbers of the three variants also showed significant association with renal dysfunction in patients with IgAN (P = 0.03; hazards ratio, 3.69; after controlling for the effects of known prognostic factors) and also with increased serum IgA1 (P = 0.02) and galactose-deficient IgA1 (P = 0.03). For replication, we confirmed the associations of DEFA1A3 (P = 4.42 × 10(-4); OR, 0.82) and DEFA3 copy numbers (P = 4.30 × 10(-3); OR, 0.74) with IgAN in a Caucasian cohort (531 cases and 198 controls) and found the 211bp variant to be much rarer in Caucasians. We also observed an association of the 211bp copy number with membranous nephropathy (P = 1.11 × 10(-7); OR, 0.74; in 493 Chinese cases and 500 matched controls), but not with diabetic kidney disease (in 806 Chinese cases and 786 matched controls). By explaining 4.96% of disease risk and influencing renal dysfunction in patients with IgAN, the DEFA1A3 CNV locus may be a potential therapeutic target for developing treatments for this disease. Copyright © 2016, American Association for the Advancement of Science.

Genome-wide copy number variation study associates metabotropic glutamate receptor gene networks with attention deficit hyperactivity disorder

PubMed Central

Elia, Josephine; Glessner, Joseph T; Wang, Kai; Takahashi, Nagahide; Shtir, Corina J; Hadley, Dexter; Sleiman, Patrick M A; Zhang, Haitao; Kim, Cecilia E; Robison, Reid; Lyon, Gholson J; Flory, James H; Bradfield, Jonathan P; Imielinski, Marcin; Hou, Cuiping; Frackelton, Edward C; Chiavacci, Rosetta M; Sakurai, Takeshi; Rabin, Cara; Middleton, Frank A; Thomas, Kelly A; Garris, Maria; Mentch, Frank; Freitag, Christine M; Steinhausen, Hans-Christoph; Todorov, Alexandre A; Reif, Andreas; Rothenberger, Aribert; Franke, Barbara; Mick, Eric O; Roeyers, Herbert; Buitelaar, Jan; Lesch, Klaus-Peter; Banaschewski, Tobias; Ebstein, Richard P; Mulas, Fernando; Oades, Robert D; Sergeant, Joseph; Sonuga-Barke, Edmund; Renner, Tobias J; Romanos, Marcel; Romanos, Jasmin; Warnke, Andreas; Walitza, Susanne; Meyer, Jobst; Pálmason, Haukur; Seitz, Christiane; Loo, Sandra K; Smalley, Susan L; Biederman, Joseph; Kent, Lindsey; Asherson, Philip; Anney, Richard J L; Gaynor, J William; Shaw, Philip; Devoto, Marcella; White, Peter S; Grant, Struan F A; Buxbaum, Joseph D; Rapoport, Judith L; Williams, Nigel M; Nelson, Stanley F; Faraone, Stephen V; Hakonarson, Hakon

2014-01-01

Attention deficit hyperactivity disorder (ADHD) is a common, heritable neuropsychiatric disorder of unknown etiology. We performed a whole-genome copy number variation (CNV) study on 1,013 cases with ADHD and 4,105 healthy children of European ancestry using 550,000 SNPs. We evaluated statistically significant findings in multiple independent cohorts, with a total of 2,493 cases with ADHD and 9,222 controls of European ancestry, using matched platforms. CNVs affecting metabotropic glutamate receptor genes were enriched across all cohorts (P = 2.1 × 10−9). We saw GRM5 (encoding glutamate receptor, metabotropic 5) deletions in ten cases and one control (P = 1.36 × 10−6). We saw GRM7 deletions in six cases, and we saw GRM8 deletions in eight cases and no controls. GRM1 was duplicated in eight cases. We experimentally validated the observed variants using quantitative RT-PCR. A gene network analysis showed that genes interacting with the genes in the GRM family are enriched for CNVs in ~10% of the cases (P = 4.38 × 10−10) after correction for occurrence in the controls. We identified rare recurrent CNVs affecting glutamatergic neurotransmission genes that were overrepresented in multiple ADHD cohorts. PMID:22138692

Oral contraceptive use, parity, and constitutional characteristics in soft tissue sarcoma: a Swedish population-based case-control study 1988-2009.

PubMed

Wagner, Philippe; Alvegård, Thor; Ranstam, Jonas; Rydholm, Anders; Vult von Steyern, Fredrik; Olsson, Håkan

2014-09-01

The study was designed to investigate the influence of surrogate factors associated with sex (SH) and growth hormones (GH) on the risk of developing soft tissue sarcomas (STS). The etiology of soft tissue sarcoma is largely unknown. We have studied the effect of hormone related factors on STS in the Swedish population between 1988 and 2009 using a population-based matched case-control design. Our study is the largest on this topic to date, including 634 cases in a primary matched analysis and 855 cases in an unmatched sensitivity analysis. We identified protective effects connected to constitutional characteristics, hormonal and reproductive factors. Being shorter than your peers at age 11 was associated with an odds ratio (OR) of 0.51 (0.36-0.74). Having used oral contraceptives (OC), OR 0.75 (0.49-1.15), and high parity, OR 0.16 (0.04-0.63), comparing three or more children to two or less, also appeared to reduce the risk of STS. The risk was further reduced with the duration of OC use (p = 0.01), comparing use for 11 years or more to use for 3 years or less yielded an OR of 0.10 (0.02-0.41). No effect was observed for ever having had perimenopausal hormone therapy OR 1.02 (0.70-1.47). The effect of BMI varied significantly with subtype (p = 0.03) and tumor location (p < 0.001). We observed surrogates of SH, GH, and insulin-like growth factor 1 to be associated with STS development. These findings are important as they may connect STSs to the group of hormone-dependent tumors, potentially revealing common treatment and prevention targets.

Is screening of TORCH worthwhile in women with bad obstetric history: an observation from eastern Nepal.

PubMed

Kumari, Namrata; Morris, Norman; Dutta, Renu

2011-02-01

This pilot case-control study at a tertiary-care hospital over a four-month period was aimed at evaluating the possible usefulness of screening of TORCH (Toxoplasma gondii, rubella virus, cytomegalovirus, and Herpes simplex virus) in females with bad obstetric history. The study included 12 women with bad obstetric history and a similar number of matched controls with previous normal pregnancies. A serological evaluation of TORCH infections was carried out by detecting IgG and IgM antibodies against these infections by ELISA test-kit. Statistical analysis was not done to compare the results relating to the two groups due to a small number of cases and controls included in the study. Ten (83.3%) of the 12 cases with bad obstetric history and two (16.7%) of the 12 healthy controls were serologically positive at least for one of the TORCH agents. The seropositivity rate in women with bad obstetric history was quite high compared to that in the normal healthy controls. The results suggest that a previous history of pregnancy wastage and the serological evaluation of TORCH infections during current pregnancy must be considered while managing cases with bad obstetric history.

Cerebral malaria and sequelar epilepsy: first matched case-control study in Gabon.

PubMed

Ngoungou, Edgard Brice; Koko, Jean; Druet-Cabanac, Michel; Assengone-Zeh-Nguema, Yvonne; Launay, Marylène Ndong; Engohang, Edouard; Moubeka-Mounguengui, Martine; Kouna-Ndouongo, Philomène; Loembe, Paul-Marie; Preux, Pierre-Marie; Kombila, Maryvonne

2006-12-01

Cerebral malaria (CM) is suspected to be a potential cause of epilepsy in tropical areas. The purpose of this article was to evaluate the relationship between CM and epilepsy in Gabon. A matched case-control study was carried out on a sample of subjects aged six months to 25 years and hospitalized between 1990 and 2004 in three hospitals in Libreville, Gabon. Cases were defined as patients suffering from epilepsy and confirmed by a neurologist. Controls were defined as patients without epilepsy. The exposure of interest was CM according to WHO criteria. In total, 296 cases and 296 controls were included. Of these, 36 (26 cases and 10 controls) had a CM history. The adjusted odds ratio (aOR) to develop epilepsy after CM was 3.9 [95% CI: 1.7-8.9], p<0.001. Additional risk factors were identified: family history of epilepsy: aOR=6.0 [95% CI: 2.6-14.1], p<0.0001, and febrile convulsions: aOR=9.2 [95% CI 4.0-21.1], p<0.0001. This first case-control study on that issue suggests that epilepsy-related CM is an underrecognized problem. It emphasizes the need for further studies to better evaluate the role of convulsions during CM.

The Effect of Latent Binary Variables on the Uncertainty of the Prediction of a Dichotomous Outcome Using Logistic Regression Based Propensity Score Matching.

PubMed

Szekér, Szabolcs; Vathy-Fogarassy, Ágnes

2018-01-01

Logistic regression based propensity score matching is a widely used method in case-control studies to select the individuals of the control group. This method creates a suitable control group if all factors affecting the output variable are known. However, if relevant latent variables exist as well, which are not taken into account during the calculations, the quality of the control group is uncertain. In this paper, we present a statistics-based research in which we try to determine the relationship between the accuracy of the logistic regression model and the uncertainty of the dependent variable of the control group defined by propensity score matching. Our analyses show that there is a linear correlation between the fit of the logistic regression model and the uncertainty of the output variable. In certain cases, a latent binary explanatory variable can result in a relative error of up to 70% in the prediction of the outcome variable. The observed phenomenon calls the attention of analysts to an important point, which must be taken into account when deducting conclusions.

Increasing maternal percentage body fat in early second trimester: a risk factor for preeclampsia.

PubMed

Wang, Yanxia; Qiu, Jie; Zhou, Min; Wang, Youjie; Du, Yukai

2015-02-01

To determine if maternal percentage body fat (PBF) or fat free mass (FFM) in the early second trimester of pregnancy influenced the development of preeclampsia. A matched nested case-control study was conducted from a cohort study of 1668 women at Gansu provincial maternal and child care hospital from July 2007 to August 2011 in China. Maternal PBF and FFM were assessed by bioelectrical impedance analysis during 12th-16th gestational week. The demographic characteristics were all chart abstracted. After childbirth, 70 cases of preeclampsia were matched by race/age with 140 uncomplicated pregnancies women. Multivariate logistic regression analysis was performed to determine the associated risk factors. Pre-pregnancy body mass index were higher in women who subsequently developed preeclampsia compared with controls (p < 0.001). During 12th-16th gestational week, there were nearly 7-fold increase in the odds of preeclampsia (adjusted OR: 6.84, 95% CI: 4.15-41.60) among women with PBF ≥ 40% versus women with PBF < 40%. But FFM were not at further increased risk of the development of preeclampsia (adjusted OR, 1.02; 95% CI, 0.6-3.6). Maternal PBF but not FFM is a predictor of preeclampsia in the early second trimester. Excessive adipose tissue possibly played an important role in developing of preeclampsia.

Role of classic signs as diagnostic predictors for enteric fever among returned travellers: Relative bradycardia and eosinopenia.

PubMed

Matono, Takashi; Kutsuna, Satoshi; Kato, Yasuyuki; Katanami, Yuichi; Yamamoto, Kei; Takeshita, Nozomi; Hayakawa, Kayoko; Kanagawa, Shuzo; Kaku, Mitsuo; Ohmagari, Norio

2017-01-01

The lack of characteristic clinical findings and accurate diagnostic tools has made the diagnosis of enteric fever difficult. We evaluated the classic signs of relative bradycardia and eosinopenia as diagnostic predictors for enteric fever among travellers who had returned from the tropics or subtropics. This matched case-control study used data from 2006 to 2015 for culture-proven enteric fever patients as cases. Febrile patients (>38.3°C) with non-enteric fever, who had returned from the tropics or subtropics, were matched to the cases in a 1:3 ratio by age (±3 years), sex, and year of diagnosis as controls. Cunha's criteria were used for relative bradycardia. Absolute eosinopenia was defined as an eosinophilic count of 0/μL. Data from 160 patients (40 cases and 120 controls) were analysed. Cases predominantly returned from South Asia (70% versus 18%, p <0.001). Relative bradycardia (88% versus 51%, p <0.001) and absolute eosinopenia (63% versus 38%, p = 0.008) were more frequent in cases than controls. In multivariate logistic regression analysis, return from South Asia (aOR: 21.6; 95% CI: 7.17-64.9) and relative bradycardia (aOR: 11.7; 95% CI: 3.21-42.5) were independent predictors for a diagnosis of enteric fever. The positive likelihood ratio was 4.00 (95% CI: 2.58-6.20) for return from South Asia, 1.72 (95% CI: 1.39-2.13) for relative bradycardia, and 1.63 (95%CI: 1.17-2.27) for absolute eosinopenia. The negative predictive values of the three variables were notably high (83-92%);. however, positive predictive values were 35-57%. The classic signs of relative bradycardia and eosinopenia were not specific for enteric fever; however both met the criteria for being diagnostic predictors for enteric fever. Among febrile returned travellers, relative bradycardia and eosinopenia should be re-evaluated for predicting a diagnosis of enteric fever in non-endemic areas prior to obtaining blood cultures.

Exposure to nonsteroidal anti-inflammatory drugs among older adult patients hospitalized for peptic ulcer disease in Argentina: A case-control study.

PubMed

Insúa, Jorge; Mavros, Panagiotis; Hunsche, Elke; Kong, Sheldon; Tibaudin-Agver, Osvaldo

2006-09-01

This study examined the association between exposure to nonselective NSAIDs and hospitalization for peptic ulcer disease (PUD) among older adults in Argentina. This was a case-control study based on the medical records of 5 hospitals in Buenos Aires. Cases were patients aged > or =50 years and hospitalized with PUD between 1997 and 2002 who were identified by mode of presentation (acute abdominal pain, vomiting, hematemesis, melena, shock, and asymptomatic anemia, or admission for an unknown reason and a discharge diagnosis related to upper gastrointestinal complications). Controls were hospitalized patients without PUD and were matched to cases (1:1) by age, sex, and admission date. NSAID exposure was defined as the use of NSAIDs during the year before admission. Conditional logistic regression analysis was used to examine the association between exposure to nonselective NSAIDs and hospitalizations for PUD, after adjusting for predictors. Subgroup analyses were conducted on patients with severe PUD, moderate PUD, and those whose PUD was confirmed by endoscopy. The study included 324 cases and 324 matched controls. The mean patient age was 74 years. The discharge diagnoses indicated severe PUD in 46.3% (150/324), moderate PUD in 49.4% (160/324), and mild PUD in 4.3% (14/324) of cases. NSAID exposure was associated with an increased risk of hospitalization for PUD (odds ratio [OR], 5.20; 95% CI, 3.31-8.15). Risk was also increased for severe PUD (OR, 4.24; 95% CI, 2.29-7.87) and moderate PUD (OR, 6.08; 95% CI, 3.09-11.96). A history of upper gastrointestinal complications was independently associated with hospitalization for PUD (OR, 14.62; 95% CI, 6.70-31.91). Use of nonselective NSAIDs is a significant risk factor for PUD-related hospitalizations among older adults in Argentina. The magnitude of the risk ratio resembles that reported for developed countries.

A sham case-control study of effectiveness of DTP-Hib-hepatitis B vaccine against rotavirus acute gastroenteritis in Kenya

PubMed Central

2014-01-01

Background In many GAVI-eligible countries, effectiveness of new vaccines will be evaluated by case-control methodology. To inform the design and assess selection bias of a future case-control study of rotavirus vaccine effectiveness (VE) in western Kenya, we performed a sham case-control study evaluating VE of pentavalent vaccine (DTP-Hib-HepB) against rotavirus acute gastroenteritis (AGE). Methods From ongoing rotavirus surveillance, we defined cases as children 12 weeks to 23 months old with EIA-confirmed rotavirus AGE. We enrolled one community-based and two hospital-based control groups. We collected vaccination status from cards at enrollment, or later in homes, and evaluated VE by logistic regression. Results We enrolled 91 cases (64 inpatient, 27 outpatient), 252 non-rotavirus AGE facility-based controls (unmatched), 203 non-AGE facility-based controls (age-matched) and 271 community controls (age-matched). Documented receipt of 3 pentavalent doses was 77% among cases and ranged from 81-86% among controls. One percent of cases and 0-2% of controls had no pentavalent doses. The adjusted odds ratio of three versus zero doses for being a case was 3.27 (95% CI 0.01-1010) for community controls and 0.69 (95% CI 0.06-7.75) for non-rotavirus hospital-based AGE controls, translating to VE of -227% and 31%, respectively, with wide confidence intervals. (No facility-based non-AGE controls were unvaccinated.) Similar results were found for ≥2 pentavalent doses and for severe rotavirus AGE. Conclusions The study showed that it is feasible to carry out a real case control in the study area, but this needs to be done as soon as the vaccine is introduced to capture the real impact. Sham case-control or pilot studies before vaccine introduction can be useful in designing case-control VE studies. PMID:24517198

A sham case-control study of effectiveness of DTP-Hib-hepatitis B vaccine against rotavirus acute gastroenteritis in Kenya.

PubMed

Khagayi, Sammy; Tate, Jacqueline E; Onkoba, Reuben; Parashar, Umesh; Odhiambo, Frank; Burton, Deron; Laserson, Kayla; Feikin, Daniel R

2014-02-11

In many GAVI-eligible countries, effectiveness of new vaccines will be evaluated by case-control methodology. To inform the design and assess selection bias of a future case-control study of rotavirus vaccine effectiveness (VE) in western Kenya, we performed a sham case-control study evaluating VE of pentavalent vaccine (DTP-Hib-HepB) against rotavirus acute gastroenteritis (AGE). From ongoing rotavirus surveillance, we defined cases as children 12 weeks to 23 months old with EIA-confirmed rotavirus AGE. We enrolled one community-based and two hospital-based control groups. We collected vaccination status from cards at enrollment, or later in homes, and evaluated VE by logistic regression. We enrolled 91 cases (64 inpatient, 27 outpatient), 252 non-rotavirus AGE facility-based controls (unmatched), 203 non-AGE facility-based controls (age-matched) and 271 community controls (age-matched). Documented receipt of 3 pentavalent doses was 77% among cases and ranged from 81-86% among controls. One percent of cases and 0-2% of controls had no pentavalent doses. The adjusted odds ratio of three versus zero doses for being a case was 3.27 (95% CI 0.01-1010) for community controls and 0.69 (95% CI 0.06-7.75) for non-rotavirus hospital-based AGE controls, translating to VE of -227% and 31%, respectively, with wide confidence intervals. (No facility-based non-AGE controls were unvaccinated.) Similar results were found for ≥2 pentavalent doses and for severe rotavirus AGE. The study showed that it is feasible to carry out a real case control in the study area, but this needs to be done as soon as the vaccine is introduced to capture the real impact. Sham case-control or pilot studies before vaccine introduction can be useful in designing case-control VE studies.

Delinquency and Recidivism: A Multicohort, Matched-Control Study of the Role of Early Adverse Experiences, Mental Health Problems, and Disabilities

ERIC Educational Resources Information Center

Barrett, David E.; Katsiyannis, Antonis; Zhang, Dalun; Zhang, Dake

2014-01-01

The authors examined the role of early adverse experiences, mental health problems, and disabilities in the prediction of juvenile delinquency and recidivism, using a matched-control group design. The delinquent group comprised 99,602 youth, born between 1981 and 1988, whose cases had been processed by the South Carolina Department of Juvenile…

Early Neuropsychological Tests as Correlates of Productivity 1 Year after Traumatic Brain Injury: A Preliminary Matched Case-Control Study

ERIC Educational Resources Information Center

Ryu, Won Hyung A.; Cullen, Nora K.; Bayley, Mark T.

2010-01-01

This study explored the relative strength of five neuropsychological tests in correlating with productivity 1 year after traumatic brain injury (TBI). Six moderate-to-severe TBI patients who returned to work at 1-year post-injury were matched with six controls who were unemployed after 1 year based on age, severity of injury, and Functional…

Keeping children safe at home: protocol for three matched case–control studies of modifiable risk factors for falls

PubMed Central

Kendrick, Denise; Stewart, Jane; Clacy, Rose; Coffey, Frank; Cooper, Nicola; Coupland, Carol; Hayes, Mike; McColl, Elaine; Reading, Richard; Sutton, Alex; M L Towner, Elizabeth; Craig Watson, Michael

2012-01-01

Background Childhood falls result in considerable morbidity, mortality and health service use. Despite this, little evidence exists on protective factors or effective falls prevention interventions in young children. Objectives To estimate ORs for three types of medically attended fall injuries in young children in relation to safety equipment, safety behaviours and hazard reduction and explore differential effects by child and family factors and injury severity. Design Three multicentre case–control studies in UK hospitals with validation of parental reported exposures using home observations. Cases are aged 0–4 years with a medically attended fall injury occurring at home, matched on age and sex with community controls. Children attending hospital for other types of injury will serve as unmatched hospital controls. Matched analyses will use conditional logistic regression to adjust for potential confounding variables. Unmatched analyses will use unconditional logistic regression, adjusted for age, sex, deprivation and distance from hospital in addition to other confounders. Each study requires 496 cases and 1984 controls to detect an OR of 0.7, with 80% power, 5% significance level, a correlation between cases and controls of 0.1 and a range of exposure prevalences. Main outcome measures Falls on stairs, on one level and from furniture. Discussion As the largest in the field to date, these case control studies will adjust for potential confounders, validate measures of exposure and investigate modifiable risk factors for specific falls injury mechanisms. Findings should enhance the evidence base for falls prevention for young children. PMID:22628151

Association between depression and diabetes amongst adults in Bangladesh: a hospital based case–control study

PubMed Central

Islam, Sheikh Mohammed Shariful; Ferrari, Uta; Seissler, Jochen; Niessen, Louis; Lechner, Andreas

2015-01-01

Methods A matched case–control study was conducted among 591 consecutive patients with diabetes attending a tertiary hospital in Dhaka and 591 controls matched for age, sex and area of residence without diabetes not related with the index–case. Depression was measured using the Patient Health Questionnaire–9. Multivariate logistic regression was performed to examine the association between depression and diabetes. Results The mean age (±standard deviation) of the participants was 50.4 ± 11.4 years, with a male to female ratio of 43:57. The prevalence of depression was 45.2% and 19.8% among cases and controls, respectively. In the multivariate analysis, mild as well as moderate to severe depression were significantly associated with diabetes and independent of sociodemographic factors and co–morbidity (adjusted odds ratio (OR) = 2.0, 95% confidence interval (CI) = 1.4–2.9 and adjusted OR = 6.4, 95% CI = 3.4–12.3; P < 0.001 for both). Conclusion The high prevalence and strong association of depression in individuals with diabetes in Bangladesh suggests that depression should be routinely screened for patients with diabetes at the clinics and that management strategies adequate for resource–poor settings need to be developed. Further research to determine the pathophysiological role of depression in the development of diabetes is merited. PMID:26649173

Postmastectomy radiation therapy for lymph node-negative, locally advanced breast cancer after modified radical mastectomy: analysis of the NCI Surveillance, Epidemiology, and End Results database.

PubMed

Yu, James B; Wilson, Lynn D; Dasgupta, Tina; Castrucci, William A; Weidhaas, Joanne B

2008-07-01

The role of postmastectomy radiotherapy (PMRT) for lymph node-negative locally advanced breast carcinoma (T3N0M0) after modified radical mastectomy (MRM) with regard to improvement in survival remains an area of controversy. The 1973-2004 National Cancer Institute (NCI) Surveillance, Epidemiology, and End Results (SEER) database was examined for patients with T3N0M0 ductal, lobular, or mixed ductal and lobular carcinoma of the breast who underwent MRM, treated from 1988-2003. Patients who were men, who had positive lymph nodes, who survived < or =6 months, for whom breast cancer was not the first malignancy, who had nonbeam radiation, intraoperative or preoperative radiation were excluded. The average treatment effect of PMRT on mortality was estimated with a propensity score case-matched analysis. In all, 1777 patients were identified; 568 (32%) patients received PMRT. Median tumor size was 6.3 cm. The median number of lymph nodes examined was 14 (range, 1-49). Propensity score matched case-control analysis showed no improvement in overall survival with the delivery of PMRT in this group. Older patients, patients with ER- disease (compared with ER+), and patients with high-grade tumors (compared with well differentiated) had increased mortality. The use of PMRT for T3N0M0 breast carcinoma after MRM is not associated with an increase in overall survival. It was not possible to analyze local control in this study given the limitations of the SEER database. The impact of potential improvement in local control as it relates to overall survival should be the subject of further investigation. (Copyright) 2008 American Cancer Society.

Statin use and risk of cholecystectomy - A case-control analysis using Swiss claims data.

PubMed

Biétry, Fabienne A; Reich, Oliver; Schwenkglenks, Matthias; Meier, Christoph R

2016-12-01

Using claims data from the Helsana Group, a large Swiss health insurance provider, we examined the association between statin use and the risk of cholecystectomy in a case-control analysis. We identified 2,200 cholecystectomy cases between 2013 and 2014 and matched 4 controls to each case on age, sex, index date and canton. We categorized statin users into current or past users (last prescription ≤ 180 or > 180 days before the index date, respectively) and classified medication use by duration based on number of prescriptions before the index date. We applied conditional logistic regression analyses to calculate odds ratios (ORs) with 95% confidence intervals (CIs) and adjusted the analyses for history of cardiovascular diseases and for use of estrogens, fibrates and other lipid-lowering agents. The adjusted OR (aOR) for cholecystectomy was 0.85 (95% CI: 0.74, 0.99) for current statin users compared to non-users. Long-term current statin use (5-19 prescriptions) was associated with a reduced OR (aOR 0.77, 95% CI: 0.65, 0.92). However, neither short-term current use nor past statin use affected the risk of cholecystectomy. The study supports the previously raised hypothesis that long-term statin use reduces the risk of cholecystectomy.

Trivalent inactivated influenza vaccine is not associated with sickle cell crises in children.

PubMed

Hambidge, Simon J; Ross, Colleen; Glanz, Jason; McClure, David; Daley, Matthew F; Xu, Stan; Shoup, Jo Ann; Narwaney, Komal; Baggs, James; Weintraub, Eric

2012-01-01

Children with sickle cell disease are considered at high risk for complications from influenza infection and are recommended to receive annual influenza vaccination. However, data on the safety of influenza vaccination in children with sickle cell anemia are sparse. Using a retrospective cohort of children aged 6 months to 17 years in 8 managed care organizations that comprise the Vaccine Safety Datalink and who had a diagnosis of sickle cell anemia from 1999 to 2006, we conducted matched case-control and self-controlled case series studies to examine the association of trivalent inactivated influenza vaccination with hospitalization for sickle cell crisis in the 2 weeks after vaccination. From an original pool of 1085 pediatric subjects with a diagnosis of sickle cell anemia, we identified 179 children with at least 1 sickle cell crisis during any influenza season (October 1-March 31). In the matched case-control study (matching on age category, gender, Vaccine Safety Datalink site, and season), the odds ratio of hospitalization for a crisis in vaccinated compared with unvaccinated children was not significant: 1.3 (95% confidence interval 0.8-2.2). In the self-controlled case series study of hospitalized cases, the incident rate ratio for hospitalization with sickle cell crisis in the 2 weeks after trivalent inactivated influenza vaccination was also not significant: 1.2 (95% confidence interval 0.75-1.95). This large cohort study did not find an association of influenza vaccination and hospitalization for sickle cell crises in children with sickle cell anemia.

Binational outbreak of Guillain-Barré syndrome associated with Campylobacter jejuni infection, Mexico and USA, 2011.

PubMed

Jackson, B R; Zegarra, J Alomía; López-Gatell, H; Sejvar, J; Arzate, F; Waterman, S; Núñez, A Sánchez; López, B; Weiss, J; Cruz, R Quintero; Murrieta, D Y López; Luna-Gierke, R; Heiman, K; Vieira, A R; Fitzgerald, C; Kwan, P; Zárate-Bermúdez, M; Talkington, D; Hill, V R; Mahon, B

2014-05-01

In June 2011, a cluster of suspected cases of Guillain-Barré syndrome (GBS), which can follow Campylobacter jejuni infection, was identified in San Luis Río Colorado (SLRC), Sonora, Mexico and Yuma County, Arizona, USA. An outbreak investigation identified 26 patients (18 from Sonora, eight from Arizona) with onset of GBS 4 May-21 July 2011, exceeding the expected number of cases (n = 1-2). Twenty-one (81%) patients reported antecedent diarrhoea, and 61% of 18 patients tested were seropositive for C. jejuni IgM antibodies. In a case-control study matched on age group, sex, ethnicity, and neighbourhood of residence, all Arizona GBS patients travelled to SLRC during the exposure period vs. 45% of matched controls (matched odds ratio 8·1, 95% confidence interval 1·5-∞). Exposure information and an environmental assessment suggested that GBS cases resulted from a large outbreak of C. jejuni infection from inadequately disinfected tap water in SLRC. Binational collaboration was essential in investigating this cross-border GBS outbreak, the first in mainland North America since 1976.

Vitamin D and Fracture Risk in Early Childhood: A Case-Control Study

PubMed Central

Anderson, Laura N.; Heong, Sze Wing; Chen, Yang; Thorpe, Kevin E.; Adeli, Khosrow; Howard, Andrew; Sochett, Etienne; Birken, Catherine S.; Parkin, Patricia C.; Maguire, Jonathon L.; Abdullah, Kawsari; Anderson, Laura N.; Birken, Catherine S.; Borkhoff, Cornelia M.; Carsley, Sarah; Chen, Yang; Katz-Lavigne, Mikael; Kavikondala, Kanthi; Kowal, Christine; Maguire, Jonathon L.; Mason, Dalah; Omand, Jessica; Parkin, Patricia C.; Persaud, Navindra; van den Heuvel, Meta; Baker, Jillian; Barozzino, Tony; Bonifacio, Joey; Campbell, Douglas; Cheema, Sohail; Chisamore, Brian; Danayan, Karoon; Das, Paul; Derocher, Mary Beth; Do, Anh; Dorey, Michael; Freeman, Sloane; Fung, Keewai; Guiang, Charlie; Handford, Curtis; Hatch, Hailey; Jacobson, Sheila; Kiran, Tara; Knowles, Holly; Kwok, Bruce; Lakhoo, Sheila; Lam-Antoniades, Margarita; Lau, Eddy; Leung, Fok-Han; Loo, Jennifer; Mahmoud, Sarah; Moodie, Rosemary; Morinis, Julia; Naymark, Sharon; Neelands, Patricia; Owen, James; Peer, Michael; Perlmutar, Marty; Persaud, Navindra; Pinto, Andrew; Porepa, Michelle; Ramji, Nasreen; Ramji, Noor; Rosenthal, Alana; Saunderson, Janet; Saxena, Rahul; Sgro, Michael; Shepherd, Susan; Smiltnieks, Barbara; Taylor, Carolyn; Weisdors, Thea; Wijayasinghe, Sheila; Wong, Peter; Ying, Ethel; Young, Elizabeth

2017-01-01

Abstract The objective of this study was to evaluate the association of vitamin D intake and serum levels with fracture risk in children under 6 years of age. A case-control study was conducted in Toronto, Ontario, Canada. Cases were recruited from the fracture clinic at the Hospital for Sick Children, and matched controls were obtained from the TARGet Kids! primary-care research network. Controls were matched to cases on age, sex, height, and season. Fracture risk was estimated from conditional logistic regression, with adjustment for skin type, fracture history, waist circumference, outdoor free play, neighborhood income, soda consumption, and child's birth weight. A total of 206 cases were recruited during May 2009–April 2013 and matched to 343 controls. Serum 25-hydroxyvitamin D concentration (per 10-nmol/L increment: adjusted odds ratio (aOR) = 0.95, 95% confidence interval (CI): 0.88, 1.03) and intake of cow's milk (<2 cups/day vs. 2 cups/day: aOR = 0.95 (95% CI: 0.60, 1.52); >2 cups/day vs. 2 cups/day: aOR = 1.39 (95% CI: 0.85, 2.23)) were not significantly associated with reduced odds of fracture. A statistically significant association was observed between child use of vitamin D supplements and decreased odds of fracture (yes vs. no: aOR = 0.42, 95% CI: 0.25, 0.69). Vitamin D supplementation, but not serum 25-hydroxyvitamin D level or milk intake, was associated with reduced fracture risk among these healthy young children. PMID:28459987

Evaluation of unique identifiers used as keys to match identical publications in Pure and SciVal - a case study from health science.

PubMed

Madsen, Heidi Holst; Madsen, Dicte; Gauffriau, Marianne

2016-01-01

Unique identifiers (UID) are seen as an effective key to match identical publications across databases or identify duplicates in a database. The objective of the present study is to investigate how well UIDs work as match keys in the integration between Pure and SciVal, based on a case with publications from the health sciences. We evaluate the matching process based on information about coverage, precision, and characteristics of publications matched versus not matched with UIDs as the match keys. We analyze this information to detect errors, if any, in the matching process. As an example we also briefly discuss how publication sets formed by using UIDs as the match keys may affect the bibliometric indicators number of publications, number of citations, and the average number of citations per publication.  The objective is addressed in a literature review and a case study. The literature review shows that only a few studies evaluate how well UIDs work as a match key. From the literature we identify four error types: Duplicate digital object identifiers (DOI), incorrect DOIs in reference lists and databases, DOIs not registered by the database where a bibliometric analysis is performed, and erroneous optical or special character recognition. The case study explores the use of UIDs in the integration between the databases Pure and SciVal. Specifically journal publications in English are matched between the two databases. We find all error types except erroneous optical or special character recognition in our publication sets. In particular the duplicate DOIs constitute a problem for the calculation of bibliometric indicators as both keeping the duplicates to improve the reliability of citation counts and deleting them to improve the reliability of publication counts will distort the calculation of average number of citations per publication. The use of UIDs as a match key in citation linking is implemented in many settings, and the availability of UIDs may become critical for the inclusion of a publication or a database in a bibliometric analysis.

Evaluation of unique identifiers used as keys to match identical publications in Pure and SciVal – a case study from health science

PubMed Central

Madsen, Heidi Holst; Madsen, Dicte; Gauffriau, Marianne

2016-01-01

Unique identifiers (UID) are seen as an effective key to match identical publications across databases or identify duplicates in a database. The objective of the present study is to investigate how well UIDs work as match keys in the integration between Pure and SciVal, based on a case with publications from the health sciences. We evaluate the matching process based on information about coverage, precision, and characteristics of publications matched versus not matched with UIDs as the match keys. We analyze this information to detect errors, if any, in the matching process. As an example we also briefly discuss how publication sets formed by using UIDs as the match keys may affect the bibliometric indicators number of publications, number of citations, and the average number of citations per publication.  The objective is addressed in a literature review and a case study. The literature review shows that only a few studies evaluate how well UIDs work as a match key. From the literature we identify four error types: Duplicate digital object identifiers (DOI), incorrect DOIs in reference lists and databases, DOIs not registered by the database where a bibliometric analysis is performed, and erroneous optical or special character recognition. The case study explores the use of UIDs in the integration between the databases Pure and SciVal. Specifically journal publications in English are matched between the two databases. We find all error types except erroneous optical or special character recognition in our publication sets. In particular the duplicate DOIs constitute a problem for the calculation of bibliometric indicators as both keeping the duplicates to improve the reliability of citation counts and deleting them to improve the reliability of publication counts will distort the calculation of average number of citations per publication. The use of UIDs as a match key in citation linking is implemented in many settings, and the availability of UIDs may become critical for the inclusion of a publication or a database in a bibliometric analysis. PMID:27635223

Risk factors for cancer cervix among rural women of a hilly state: a case-control study.

PubMed

Thakur, Anita; Gupta, Bhupender; Gupta, Anmol; Chauhan, Raman

2015-01-01

In Himachal Pradesh, cancer cervix is a major public health problem since it ranks as the number one female cancer. A case-control study of 226 newly diagnosed, histopathologically confirmed cases of cancer cervix and equal number of matched controls was conducted at Regional Cancer Center, Himachal Pradesh during the period from July 2008 to October 2009 with the objective to study the common factors associated with cancer cervix. Univariate analysis identified 10 risk factors associated significantly with the disease. On multiple logistic regression, however, only seven risk factors were found to be associated significantly with the disease. These were: Age at birth of first child, spacing between two children, age at marriage, literacy, socioeconomic status, multiparity, and poor genital hygiene. Risk factors such as poor genital hygiene, age at birth of first child <19 years, early marriage, illiteracy, multiparity, and low socioeconomic status were highly prevalent in the study subjects and were found to be significantly associated with cancer cervix.

Exposure to professional pest control treatments and the risk of childhood acute lymphoblastic leukemia.

PubMed

Bailey, Helen D; Armstrong, Bruce K; de Klerk, Nicholas H; Fritschi, Lin; Attia, John; Scott, Rodney J; Smibert, Elizabeth; Milne, Elizabeth

2011-10-01

Previous studies suggest that exposure to pesticides increases the risk of childhood acute lymphoblastic leukemia (ALL). The aim of this analysis was to investigate whether professional pest treatments in or around the home before birth or during childhood increased the risk of childhood ALL. Data from 388 cases and 870 frequency-matched controls were analyzed using unconditional logistic regression, adjusting for study matching variables and potential confounders, to calculate odds ratios (ORs). A meta-analysis of our findings with the published findings of previous studies was also conducted. The ORs for any professional pest control treatments were 1.19 (95% CI 0.83, 1.69) in the year before pregnancy, 1.30 (95% CI 0.86, 1.97) during pregnancy and 1.24 (95% CI 0.93, 1.65) for those done after the child's birth. The ORs for exposure after birth were highest when it occurred between the ages of two and three years. ORs were elevated for termite treatments before birth. ORs were higher for pre-B than T cell ALL and for t(12;21) (ETV6-Runx-1) than other cytogenetic sub-types. The pooled OR from a meta-analysis of our study with three previous studies of professional pest control treatments during pregnancy was 1.37 (95% CI 1.00, 1.88). Our results, and those of our meta-analysis, provide some evidence of a modestly increased risk of ALL for professional pest control treatments done during the index pregnancy and possibly in the child's early years. The analysis of pooled data from international collaborations may provide more certainty regarding these potentially important associations. Copyright © 2011 UICC.

Non-tuberculous mycobacterial bloodstream infections in patients with indwelling vascular catheters - the role of sickle cell anaemia.

PubMed

Edun, Babatunde; Shah, Ansal; Durkin, Martin; Whitmire, Melanie; Williams, Shanetta Patterson; Albrecht, Helmut; Al-Hasan, Majdi; Weissman, Sharon

2017-05-01

Few studies have examined risk factors for nontuberculous mycobacteria (NTM) bloodstream infections (BSI) involving indwelling vascular catheters (IDVC). Sickle cell anaemia (HbSS/SC) is known to affect several aspects of the immune system leading to relative immune deficiency. The purpose of this retrospective nested case-control study was to determine if HbSS/SC is a risk factor for NTM BSI among individuals with IDVCs. All NTM IDVC infections (cases) at two tertiary hospitals from 2008 to 2014 were reviewed. Cases were matched 2:1 with controls who had IDVC infections due to organisms other than NTM. Matching criteria included age within 10 years and IDVC infection within three months of index case. Logistic regression was used to identify risk factors for IDVC infection due to NTM. Nineteen NTM BSIs were identified. Three cases were excluded because they did not have IDVCs at the time their BSI was identified. Sixteen cases of NTM IDVC infection were matched to 32 controls with IDVC infections due to other organisms. The mean age of patients with IDVC infections was 48.5 years and 28 (58%) were male. Compared to the control group those with NTM BSI were more likely to have HbSS/SC 38% (6/16) versus 6% (2/32) (p = .006). IDVCs are a risk factor for NTM BSI. Sickle cell anaemia appears to be a risk factor for IDVC infections due to NTM. This study is limited by the small sample size. A larger study is needed to further investigate the association between HbSS/SC and NTM IDVC infections.

Contemporary Risk Factors and Outcomes of Transfusion-Associated Circulatory Overload.

PubMed

Roubinian, Nareg H; Hendrickson, Jeanne E; Triulzi, Darrell J; Gottschall, Jerome L; Michalkiewicz, Michael; Chowdhury, Dhuly; Kor, Daryl J; Looney, Mark R; Matthay, Michael A; Kleinman, Steven H; Brambilla, Donald; Murphy, Edward L

2018-04-01

Transfusion-associated circulatory overload is characterized by hydrostatic pulmonary edema following blood transfusion. Restrictive transfusion practice may affect the occurrence and severity of transfusion-associated circulatory overload in critically ill patients. We sought to examine contemporary risk factors and outcomes for transfusion-associated circulatory overload. Case-control study. Four tertiary care hospitals. We prospectively enrolled 200 patients with transfusion-associated circulatory overload identified by active surveillance and 405 controls matched by transfusion intensity. None. Among 20,845 transfused patients who received 128,263 blood components from May 2015 until July 2016, transfusion-associated circulatory overload incidence was one case per 100 transfused patients. In addition to cardiovascular comorbidities, multivariable analysis identified the following independent predictors of transfusion-associated circulatory overload: acute kidney injury, emergency surgery, pretransfusion diuretic use, and plasma transfusion-the latter especially in females. Compared with matched controls, transfusion-associated circulatory overload cases were more likely to require mechanical ventilation (71% vs 49%; p < 0.001), experienced longer intensive care and hospital lengths of stay following transfusion, and had higher mortality (21% vs 11%; p = 0.02) even after adjustment for other potentially confounding variables. Despite restrictive transfusion practice, transfusion-associated circulatory overload remains a frequent complication of transfusion and is an independent risk factor for in-hospital morbidity and mortality. In addition to cardiovascular and renal risk factors, plasma transfusion was associated with transfusion-associated circulatory overload after controlling for other covariates. Additional research is needed to examine the benefit of reduced erythrocyte or plasma exposure in patients at high risk for transfusion-associated circulatory overload.

COSTS OF INTERSTITAL CYSTITIS IN A MANAGED CARE POPULATION

PubMed Central

Clemens, J. Quentin; Meenan, Richard T.; O’Keeffe Rosetti, Maureen C.; Kimes, Terry; Calhoun, Elizabeth A.

2008-01-01

Objective This study assessed the direct medical costs, medication and procedure use associated with interstitial cystitis (IC) in women in the Kaiser Permanente Northwest (KPNW) managed care population. Methods The KPNW electronic medical record was utilized to identify women diagnosed with interstitial cystitis (n=239). Each of these cases was matched with three controls based on age and duration in the health plan. Health plan cost accounting data were used to determine inpatient, outpatient, and pharmacy costs for 1998-2003. An analysis of prescription medication use, cystoscopic and urodynamic procedures commonly associated with IC was also performed. To evaluate for comorbidities, an automated risk-adjustment model (RxRisk) linked to 28 chronic medical conditions was applied to the administrative datasets from both groups. Results The mean duration from the date of IC diagnosis to the end of the study period was 36.6 months (range 1.4-60). Mean yearly costs were 2.4-fold greater in cases than controls ($7100 vs. $2994), and median yearly costs were 3.8-fold greater ($5000 vs. $1304). These cost differences were predominantly due to outpatient and pharmacy expenses. Medication and procedure use were significantly greater in cases than controls. These findings were consistent across RxRisk categories, which suggest that the observed cost differences are IC-specific. Conclusions The direct per-person costs of IC are high, with average yearly costs approximately $4000 greater than age-matched controls. This cost differential is an underestimate, as costs preceding the diagnosis, use of alternative therapies, indirect costs and costs of those with IC that is not diagnosed are not included. PMID:18329077

Comparison of MRI-assessed body fat content between lean women with polycystic ovary syndrome (PCOS) and matched controls: less visceral fat with PCOS.

PubMed

Dolfing, Jacoba G; Stassen, Chrit M; van Haard, Paul M M; Wolffenbuttel, Bruce H R; Schweitzer, Dave H

2011-06-01

BACKGROUND Polycystic ovary syndrome (PCOS) is a heterogeneous disorder. However, PCOS has a strong resemblance to the metabolic syndrome, including preponderance of visceral fat deposition. The aim of this study is to compare fat distribution between lean women with PCOS and controls matched for body composition but with regular menstrual cycles and proven fertility. METHODS In this prospective cross-sectional study in a fertility outpatient clinic, 10 Caucasian women with PCOS and 10 controls, all with a BMI between 19 and 25 kg/m(2), were included. Fasting glucose, insulin and C-peptide concentrations, homeostasis model assessment (HOMA), hormonal levels and bioelectrical impedance analysis (BIA) variables were assessed and fat content and ovarian volume determinations were obtained with magnetic resonance imaging (MRI). Multiple axial cross-sections were calculated. RESULTS The age of the PCOS and control groups were [mean (SD)] 28.2 years (2.6) versus 33.7 years (2.3) P < 0.0001, respectively, and both groups were matched for BMI: 21.6 kg/m(2) (1.1) versus 21.8 kg/m(2) (2.1) (ns), fasting glucose, insulin, C-peptide, HOMA-insulin resistance (IR) levels and BIA parameters. PCOS cases had higher ovarian volumes and less visceral fat compared with controls. CONCLUSIONS Lean women with PCOS have higher MRI-determined ovarian volumes and less visceral fat content when compared with control women.

Continuing use of antithrombotic medications for patients with bleeding gastroduodenal ulcer requiring endoscopic hemostasis: a case-control study.

PubMed

Kawasaki, Keisuke; Nakamura, Shotaro; Kurahara, Koichi; Nagasue, Tomohiro; Yanai, Shunichi; Harada, Akira; Yaita, Hiroki; Fuchigami, Tadahiko; Matsumoto, Takayuki

2017-09-01

The aim of this study was to compare clinical characteristics and outcomes of bleeding gastroduodenal ulcer between patients taking antithrombotic medications and those not taking antithrombotic medications. We performed a case-control study of 346 patients with endoscopically verified bleeding gastroduodenal ulcer, which included 173 cases taking antithrombotic medications throughout peri-bleeding period and 173 age- and sex-matched controls not taking antithrombotic medications. The cases showed less frequent Helicobacter pylori (H. pylori) infections (45.1% versus 60.7%, p = .005), more frequent duodenal location (31.8% versus 19.1%, p = .009), and more frequent rebleeding (13.9% versus 5.8%, p = .02) than the controls. Multivariate analysis revealed that duodenal location (odds ratio [OR] 3.01, 95% confidence interval [CI] 1.37-6.65) and use of antithrombotic medications (OR 2.47, 95% CI 1.13-5.77) were independent factors for rebleeding. However, there were no differences in clinical outcomes, including final successful endoscopic hemostasis, need for surgical intervention, and mortality between cases and controls. Thromboembolic events did not occur in any cases and controls during the periendoscopic period. Low prevalence of H. pylori infection, frequent duodenal location, and high rebleeding rate are characteristics of patients with bleeding gastroduodenal ulcer under antithrombotic medications. Continuation of antithrombotic medications can be accepted for bleeding gastroduodenal ulcer.

[A case-control study on the relationship of crocidolite pollution in drinking water with the risk of gastrointestinal cancer in Dayao County].

PubMed

Mi, Jing; Peng, Wenjia; Jia, Xianjie; Wei, Binggan; Yang, Linsheng; Hu, Liming; Lu, Rong'an

2015-01-01

To explore the relationship of crocidolite pollution in drinking water with the risk of gastrointestinal cancer's death in Dayao County. A 1:2 matched case-control study involving 54 death cases of gastrointestinal cancer from a population-based cohort of twenty-seven years and 108 controls matched by age, gender, death time, etc was conducted to analyze the effect of local water condition on the risk of gastrointestinal cancer in Dayao County. Results from logistic regression analysis suggested the longer of asbestos furnace use over time, the higher the mortality risk of gastrointestinal cancer (6 - 10 years: OR = 2.920, 95% CI 1.501 - 5.604. 11 - 15 years: OR = 3.966, 95% CI 2.156 -7.950. Over 15 years: OR = 4.122, 95% CI 1.211 - 7. 584). Drinking unboiled water leaded to an increased risk of gastrointestinal cancer (OR = 1.43, 95% CI 1.07 - 1.88). Type of drinking water was associated with gastrointestinal cancer. When compared with drinking tap water, OR for drinking well water was 1.770 (95% CI 1.001 - 2.444), 2.442 for drinking river water (95% CI 0.956 - 3.950), 2.554 for drinking house and field ditch water (95% CI 1.961 - 6.584), and 3.121 for drinking pond water (95% CI 1.872 - 6.566). Related factors of drinking water in crocidolite-contaminated area in Dayao County were significantly associated with the mortality of gastrointestinal cancer.

Non-specific effect of measles vaccination on overall child mortality in an area of rural India with high vaccination coverage: a population-based case-control study.

PubMed

Kabir, Zubair; Long, Jean; Reddaiah, Vankadara P; Kevany, John; Kapoor, Suresh K

2003-01-01

To determine whether vaccination against measles in a population with sustained high vaccination coverage and relatively low child mortality reduces overall child mortality. In April and May 2000, a population-based, case-control study was conducted at Ballabgarh (an area in rural northern India). Eligible cases were 330 children born between 1 January 1991 and 31 December 1998 who died aged 12-59 months. A programme was used to match 320 controls for age, sex, family size, and area of residence from a birth cohort of 15 578 born during the same time period. The analysis used 318 matched pairs and suggested that children aged 12-59 months who did not receive measles vaccination in infancy were three times more likely to die than those vaccinated against measles. Children from lower caste households who were not vaccinated in infancy had the highest risk of mortality (odds ratio, 8.9). A 27% increase in child mortality was attributable to failure to vaccinate against measles in the study population. Measles vaccine seems to have a non-specific reducing effect on overall child mortality in this population. If true, children in lower castes may reap the greatest gains in survival. The findings should be interpreted with caution because the nutritional status of the children was not recorded and may be a residual confounder. "All-cause mortality" is a potentially useful epidemiological endpoint for future vaccine trials.

The psychosocial work environment is associated with risk of stroke at working age.

PubMed

Jood, Katarina; Karlsson, Nadine; Medin, Jennie; Pessah-Rasmussen, Hélène; Wester, Per; Ekberg, Kerstin

2017-07-01

Objective The aim of this study was to explore the relation between the risk of first-ever stroke at working age and psychological work environmental factors. Methods A consecutive multicenter matched 1:2 case-control study of acute stroke cases (N=198, age 30-65 years) who had been working full-time at the time of their stroke and 396 sex- and age-matched controls. Stroke cases and controls answered questionnaires on their psychosocial situation during the previous 12 months. The psychosocial work environment was assessed using three different measures: the job-control-demand model, the effort-reward imbalance (ERI) score, and exposures to conflict at work. Results Among 198 stroke cases and 396 controls, job strain [odds ratio (OR) 1.30, 95% confidence interval (95% CI) 1.05-1.62], ERI (OR 1.28, 95% CI 1.01-1.62), and conflict at work (OR 1.75, 95% CI 1.07-2.88) were independent risk factors of stroke in multivariable regression models. Conclusions Adverse psychosocial working conditions during the past 12 months were more frequently observed among stroke cases. Since these factors are presumably modifiable, interventional studies targeting job strain and emotional work environment are warranted.

Cost Analysis of an Intervention to Prevent Methicillin-Resistant Staphylococcus Aureus (MRSA) Transmission

PubMed Central

Chowers, Michal; Carmeli, Yehuda; Shitrit, Pnina; Elhayany, Asher; Geffen, Keren

2015-01-01

Introduction Our objective was to assess the cost implications of a vertical MRSA prevention program that led to a reduction in MRSA bacteremia. Methods We performed a matched historical cohort study and cost analysis in a single hospital in Israel for the years 2005-2011. The cost of MRSA bacteremia was calculated as total hospital cost for patients admitted with bacteremia and for patients with hospital-acquired bacteremia, the difference in cost compared to matched controls. The cost of prevention was calculated as the sum of the cost of microbiology tests, single-use equipment used for patients in isolation, and infection control personnel. Results An average of 20,000 patients were screened yearly. The cost of prevention was $208,100 per year, with the major contributor being laboratory cost. We calculated that our intervention averted 34 cases of bacteremia yearly: 17 presenting on admission and 17 acquired in the hospital. The average cost of a case admitted with bacteremia was $14,500, and the net cost attributable to nosocomial bacteremia was $9,400. Antibiotics contributed only 0.4% of the total disease management cost. When the annual cost of averted cases of bacteremia and that of prevention were compared, the intervention resulted in annual cost savings of $199,600. Conclusions A vertical MRSA prevention program targeted at high-risk patients, which was highly effective in preventing bacteremia, is cost saving. These results suggest that allocating resources to targeted prevention efforts might be beneficial even in a single institution in a high incidence country. PMID:26406889

Humidifier Disinfectants Are a Cause of Lung Injury among Adults in South Korea: A Community-Based Case-Control Study

PubMed Central

Kwon, Geun-Yong; Gwack, Jin; Park, Young-Joon; Youn, Seung-Ki; Kwon, Jun-Wook; Yang, Byung-Guk; Lee, Moo-Song; Jung, Miran; Lee, Hanyi; Jun, Byung-Yool; Lim, Hyun-Sul

2016-01-01

Backgrounds An outbreak of lung injury among South Korean adults was examined in a hospital-based case-control study, and the suspected cause was exposure to humidifier disinfectant (HD). However, a case-control study with community-dwelling controls was needed to validate the previous study’s findings, and to confirm the exposure-response relationship between HD and lung injury. Methods Each case of lung injury was matched with four community-dwelling controls, according to age (±3 years), sex, residence, and history of childbirth since 2006 (for women). Environmental risk factors, which included type and use of humidifier and HD, were investigated using a structured questionnaire during August 2011. The exposure to HD was calculated for both cases and controls, and the corresponding risks of lung injury were compared. Results Among 28 eligible cases, 16 patients agreed to participate, and 60 matched controls were considered eligible for this study. The cases were more likely to have been exposed to HD (odds ratio: 116.1, 95% confidence interval: 6.5–2,063.7). All cases were exposed to HDs containing polyhexamethyleneguanidine phosphate, and the risk of lung injury increased with the cumulative exposure, duration of exposure, and exposure per day. Conclusions This study revealed a statistically significant exposure-response relationship between HD and lung injury. Therefore, continuous monitoring and stricter evaluation of environmental chemicals’ safety should be conducted. PMID:26990641

Treatment outcomes for inpatients with obsessive-compulsive personality disorder: An open comparison trial.

PubMed

Smith, Ryan; Shepard, Christopher; Wiltgen, Anika; Rufino, Katrina; Fowler, J Christopher

2017-02-01

The current case-control study compared rates of clinically significant and reliable change in psychopathology and global functioning, prevalence of clinical deterioration, and rates of symptom remission among adult patients with obsessive compulsive personality disorder OCPD (n=52) and well-matched inpatients with any other personality disorder (n=56) and no personality disorder (n=53). Propensity score matching (PSM) was utilized to select patients matched on specific criteria present in the OCPD group. Multivariate analysis of variance models measured differences in admission functioning and RCI change across depression and anxiety severity, emotion dysregulation and suicidal ideation. Patients diagnosed with OCPD admit to treatment with higher rates of depression, anxiety, difficulty with emotion regulation and non-acceptance of emotional experience than inpatient controls. Furthermore, OCPD patients respond to treatment at a similar rate to inpatient controls, but experience lower rates of anxiety remission upon discharge. Post-hoc analyses indicate individuals meeting stubbornness and rigidity (OCPD Criteria 8) were nine times more likely to report moderate to severe anxiety at point of discharge. Limitations include a predominantly Caucasian, inpatient sample, use of self-report measures and a non-manualized treatment approach. Overall, OCPD inpatients benefit from an intensive multimodal psychiatric treatment, but experience more anxiety than non-PD patients upon discharge. Copyright © 2016 Elsevier B.V. All rights reserved.

Is Statin Use Associated With Tendon Rupture? A Population-Based Retrospective Cohort Analysis.

PubMed

Contractor, Tahmeed; Beri, Abhimanyu; Gardiner, Joseph C; Tang, Xiaoqin; Dwamena, Francesca C

2015-01-01

Previous case reports and small studies have suggested that 3-hydroxy-3-methylglutaryl-CoA reductase inhibitors (HMG-CoA-Is) may increase the risk of tendon rupture. We conducted a population-based retrospective cohort evaluation to better assess this relationship. From approximately 800,000 enrollees of a private insurance database, those who were aged ≤64 years with at least 1 year of continuous enrollment were selected. Exposure was defined as initiation of HMG-CoA-I after the beginning of the study period. Each exposed person was matched with 2 controls of similar age and gender. Baseline characteristics, including known risk factors for tendon rupture, were compared between exposed and control cohorts with fidelity to the study's matched design. After adjusting for differences in follow-up and baseline characteristics, incidence rate ratios for tendon rupture was assessed in HMG-CoA-I users and nonusers. A total of 34,749 exposed patients were matched with 69,498 controls. There was no difference in the occurrence of tendon ruptures in HMG-CoA-I users versus nonusers. The results remained unchanged after adjustment for age and gender. In conclusion, this population-based retrospective cohort evaluation suggests that use of HMG-CoA-Is as a group are not associated with tendon rupture.

Possible association between hyperthyroidism in pregnant women and obstructive congenital abnormalities of urinary tract in their offspring--a population-based case-control study.

PubMed

Bánhidy, Ferenc; Puhó, Erzsébet H; Czeizel, Andrew E

2011-02-01

The teratogenic potential of some antithyroid drugs is known, but the aim of the study was to estimate the risk of congenital abnormalities (CAs) in the offspring of pregnant women with hyperthyroidism with or without antithyroid drug treatment. Comparison of the occurrence of medically recorded hyperthyroidism who had malformed fetuses/newborns (cases) and who delivered healthy babies (controls) in the population-based Hungarian Case-Control Surveillance System of CAs, 1980-1996. Of 22,843 cases with congenital abnormalities, 71 (0.31%) while of 38,151 controls, 116 (0.30%) had mothers with hyperthyroidism. The rate of hyperthyroidism in the mothers of cases with different CAs and in the mothers of matched controls was compared. Preeclampsia-eclampsia occurred more frequently in pregnant women with hyperthyroidism without antithyroid treatment. The analysis of specific groups of CAs showed an association between hyperthyroidism in pregnant women and obstructive defects of urinary tract in their children. The lack of appropriate treatment of pregnant women affected with hyperthyroidism seems to be the major problem, because it would be necessary to prevent the hyperthyroidism related risks of pregnancy complications and CAs which exceed the risk of antithyroid medication in these pregnant women.

HPV and cofactors for invasive cervical cancer in Morocco: a multicentre case-control study.

PubMed

Berraho, Mohamed; Amarti-Riffi, Afaf; El-Mzibri, Mohammed; Bezad, Rachid; Benjaafar, Noureddine; Benideer, Abdelatif; Matar, Noureddine; Qmichou, Zinab; Abda, Naima; Attaleb, Mohammed; Znati, Kaoutar; El Fatemi, Hind; Bendahhou, Karima; Obtel, Majdouline; Filali Adib, Abdelhai; Mathoulin-Pelissier, Simone; Nejjari, Chakib

2017-06-20

Limited national information is available in Morocco on the prevalence and distribution of HPV-sub-types of cervical cancer and the role of other risk factors. The aim was to determine the frequency of HPV-sub-types of cervical cancer in Morocco and investigate risk factors for this disease. Between November 2009 and April 2012 a multicentre case-control study was carried out. A total of 144 cases of cervical cancer and 288 age-matched controls were included. Odds-ratios and corresponding confidence-intervals were computed by conditional logistic regression models. Current HPV infection was detected in 92.5% of cases and 13.9% of controls. HPV16 was the most common type for both cases and controls. Very strong associations between HPV-sub-types and cervical cancer were observed: total-HPV (OR = 39), HPV16 (OR = 49), HPV18 (OR = 31), and multiple infections (OR = 13). Education, high parity, sexual intercourse during menstruation, history of sexually transmitted infections, and husband's multiple sexual partners were also significantly associated with cervical cancer in the multivariate analysis. Our results could be used to establish a primary prevention program and to prioritize limited screening to women who have specific characteristics that may put them at an increased risk of cervical cancer.

The association between human papillomavirus infection and lung cancer: a system review and meta-analysis

PubMed Central

Xiong, Wei-Min; Xu, Qiu-Ping; Li, Xu; Xiao, Ren-Dong; Cai, Lin; He, Fei

2017-01-01

To estimate the global attributable fraction of human papillomavirus (HPV) in lung cancer, we provided updated information through a system review and meta-analysis. We did a literature search on PubMed, Ovid and Web of Science to identify case-control studies and cohort studies that detected HPV in lung carcinomas. We included studies that tested 30 or more cases and were published before Feb 28, 2017. We collected information about gender, smoking status, HPV detection methods, HPV types, materials and clinical features. If it was not possible to abstract the required information directly from the papers, we contacted the authors. A meta-analysis was performed to calculate the pooled effect sizes (OR/RR) with 95% confidence intervals (CI) including subgroup analysis and meta-regression to explore sources of heterogeneity, by Stata 13.0 software. 36 case-control studies, contributing data for 6,980 cases of lung cancer and 7,474 controls from 17 countries and one cohort study with 24,162 exposed and 1,026,986 unexposed from China were included. HPV infection was associated with cancer of lung, pooled OR was 3.64 (95% CI: 2.60–5.08), calculated with the random-effects model. Pooled OR for allogeneic case-control studies, self-matched case-control studies and nested case-control studies were 6.71 (95% CI: 4.07–11.07), 2.59 (95% CI: 1.43–4.69) and 0.92 (95% CI: 0.63–1.36), respectively. Pooled OR for HPV 16 and HPV 18 infection, were 3.14 (95% CI: 2.07–4.76) and 2.25 (95% CI: 1.49–3.40), respectively. We also found that HPV infection may be associated with squamous cell carcinoma, adenocarcinoma and small cell carcinoma. There is evidence that HPV infection, especially HPV 16 and HPV 18 infection, significantly increase the risk of lung cancer. Future research needs to focus attention toward whether an HPV vaccine can effectively reduce the incidence of lung cancer. PMID:29221217

Crayfish: a newly recognized vehicle for vibrio infections.

PubMed

Bean, N H; Maloney, E K; Potter, M E; Korazemo, P; Ray, B; Taylor, J P; Seigler, S; Snowden, J

1998-10-01

We conducted a 1-year case-control study of sporadic vibrio infections to identify risk factors related to consumption of seafood products in two coastal areas of Louisiana and Texas. Twenty-six persons with sporadic vibrio infections and 77 matched controls were enrolled. Multivariate analysis revealed that crayfish (P < 0.025) and raw oysters (P < 0.009) were independently associated with illness. Species-specific analysis revealed an association between consumption of cooked crayfish and Vibrio parahemolyticus infection (OR 9.24, P < 0.05). No crayfish consumption was reported by persons with V. vulnificus infection. Although crayfish had been suspected as a vehicle for foodborne disease, this is the first time to our knowledge that consumption of cooked crayfish has been demonstrated to be associated with vibrio infection.

Music evoked autobiographical memory after severe acquired brain injury: preliminary findings from a case series.

PubMed

Baird, A; Samson, S

2014-01-01

Music evoked autobiographical memories (MEAMs) have been characterised in the healthy population, but not, to date, in patients with acquired brain injury (ABI). Our aim was to investigate music compared with verbal evoked autobiographical memories. Five patients with severe ABI and matched controls completed the experimental music (MEAM) task (a written questionnaire) while listening to 50 "Number 1 Songs of the Year" (from 1960 to 2010). Patients also completed the Autobiographical Memory Interview (AMI) and a standard neuropsychological assessment. With the exception of Case 5, who reported no MEAMs and no autobiographical incidents on the AMI and who also had impaired pitch perception, the range of frequency and type of MEAMs in patients was broadly in keeping with their matched controls. The relative preservation of MEAMs in four cases was particularly noteworthy given their impaired verbal and/or visual anterograde memory, and in three cases, autobiographical memory impairment. The majority of MEAMs in both cases and matched controls were of a person/people or a period of life. In three patients music was more efficient at evoking autobiographical memories than the AMI verbal prompts. This is the first study of MEAMs after ABI. The findings suggest that music is an effective stimulus for eliciting autobiographical memories, and may be beneficial in the rehabilitation of autobiographical amnesia, but only in patients without a fundamental deficit in autobiographical recall memory and intact pitch perception.

Effectiveness of one dose of mumps vaccine against clinically diagnosed mumps in Guangzhou, China, 2006–2012

PubMed Central

Fu, Chuanxi; Xu, Jianxiong; Cai, Yuanjun; He, Qing; Zhang, Chunhuan; Chen, Jian; Dong, Zhiqiang; Hu, Wensui; Wang, Hui; Zhu, Wei; Wang, Ming

2013-01-01

Although mumps-containing vaccines were introduced in China in 1990s, mumps continues to be a public health concern due to the lack of decline in reported mumps cases. To assess the mumps vaccine effectiveness (VE) in Guangzhou, China, we performed a 1:1 matched case-control study. Among children in Guangzhou aged 8 mo to 12 y during 2006 to 2012, we matched one healthy child to each child with clinically diagnosed mumps. Cases with clinically diagnosed mumps were identified from surveillance sites system and healthy controls were randomly sampled from the Children’s Expanded Programmed Immunization Administrative Computerized System in Guangzhou. Conditional logistic regression was used to calculate VE. We analyzed the vaccination information for 1983 mumps case subjects and 1983 matched controls and found that the overall VE for 1 dose of mumps vaccine, irrespective of the manufacture, was 53.6% (95% confidence interval [CI], 41.0–63.5%) to children aged 8 mo to 12 y. This post-marketing mumps VE study found that immunization with one dose of the mumps vaccine confers partial protection against mumps disease. Evaluation of the VE for the current mumps vaccines, introduction of a second dose of mumps vaccine, and assessment of modifications to childhood immunization schedules is essential. PMID:23955378

Effectiveness of one dose of mumps vaccine against clinically diagnosed mumps in Guangzhou, China, 2006-2012.

PubMed

Fu, Chuanxi; Xu, Jianxiong; Cai, Yuanjun; He, Qing; Zhang, Chunhuan; Chen, Jian; Dong, Zhiqiang; Hu, Wensui; Wang, Hui; Zhu, Wei; Wang, Ming

2013-12-01

Although mumps-containing vaccines were introduced in China in 1990s, mumps continues to be a public health concern due to the lack of decline in reported mumps cases. To assess the mumps vaccine effectiveness (VE) in Guangzhou, China, we performed a 1:1 matched case-control study. Among children in Guangzhou aged 8 mo to 12 y during 2006 to 2012, we matched one healthy child to each child with clinically diagnosed mumps. Cases with clinically diagnosed mumps were identified from surveillance sites system and healthy controls were randomly sampled from the Children's Expanded Programmed Immunization Administrative Computerized System in Guangzhou. Conditional logistic regression was used to calculate VE. We analyzed the vaccination information for 1983 mumps case subjects and 1983 matched controls and found that the overall VE for 1 dose of mumps vaccine, irrespective of the manufacture, was 53.6% (95% confidence interval [CI], 41.0-63.5%) to children aged 8 mo to 12 y. This post-marketing mumps VE study found that immunization with one dose of the mumps vaccine confers partial protection against mumps disease. Evaluation of the VE for the current mumps vaccines, introduction of a second dose of mumps vaccine, and assessment of modifications to childhood immunization schedules is essential.

Maternal and paternal occupational exposures and hepatoblastoma: results from the HOPE study through the Children's Oncology Group.

PubMed

Janitz, Amanda E; Ramachandran, Gurumurthy; Tomlinson, Gail E; Krailo, Mark; Richardson, Michaela; Spector, Logan

2017-07-01

Little is known about the etiology of hepatoblastoma. We aimed to confirm the results of a previous study evaluating the association between parental occupational exposures and hepatoblastoma. In our case-control study, we identified cases (n=383) from the Children's Oncology Group and controls from birth certificates (n=387), which were frequency matched to cases on year and region of birth, sex, and birth weight. Occupational exposure in the year before and during the index pregnancy was collected through maternal interview and analyzed using unconditional logistic regression. The odds of both paternal and maternal "Likely" exposure to paints was elevated among cases compared with controls (paternal odds ratio (OR): 1.71, 95% confidence interval (CI): 1.04, 2.81; maternal OR: 3.29, 95% CI: 0.32, 33.78) after adjustment for matching factors and the confounding factors of maternal race (maternal only) and household income. In addition, paternal exposure to other chemicals was also elevated when adjusting for matching factors only (OR: 1.53, 95% CI: 1.02, 2.30). The results of our study provide further evidence of an association between parental occupation and hepatoblastoma. These results warrant further investigation of the etiologically relevant timing of occupational exposure to fumes and chemicals related to hepatoblastoma.

Campylobacteriosis in New Zealand: results of a case-control study.

PubMed

Eberhart-Phillips, J; Walker, N; Garrett, N; Bell, D; Sinclair, D; Rainger, W; Bates, M

1997-12-01

To identify and assess the contributions of major risk factors for campylobacteriosis in New Zealand. Case-control study. Home interviews were conducted over nine months using a standardised questionnaire to assess recent food consumption and other exposures. Four centres in New Zealand with high notification rates of campylobacter infections--Auckland, Hamilton, Wellington, and Christchurch. Case patients were 621 people notified between 1 June 1994 and 28 February 1995 as having campylobacter infection. Control subjects were selected randomly from telephone directories, and were matched 1:1 with case patients in relation to sex, age group, and home telephone prefix. Risk of campylobacteriosis was strongly associated with recent consumption of raw or undercooked chicken (matched odds ratio 4.52, 95% confidence interval 2.88, 7.10). There was also an increased risk with chicken eaten in restaurants (matched odds ratio 3.85; 2.52, 5.88). Recent consumption of baked or roasted chicken seemed to be protective. Campylobacteriosis was also associated with recent overseas travel, rainwater as a source of water at home, consumption of raw dairy products, and contact with puppies and cattle, particularly calves. Improperly cooked chicken seems to be associated with a large proportion of campylobacteriosis in New Zealand. Thorough cooking of chicken in homes and restaurants could reduce considerably the incidence of this disease.

A nested case-control study of predictors for tuberculosis recurrence in a large UK Centre.

PubMed

Rosser, Andrew; Richardson, Matthew; Wiselka, Martin J; Free, Robert C; Woltmann, Gerrit; Mukamolova, Galina V; Pareek, Manish

2018-02-27

Tuberculosis (TB) recurrence represents a challenge to control programs. In low incidence countries, the prevailing risk factors leading to recurrence are poorly characterised. We conducted a nested case-control study using the Leicester TB service TBIT database. Cases were identified from database notifications between 1994 and 2014. Controls had one episode and were matched to cases on a ratio of two to one by the date of notification. Multiple imputation was used to account for missing data. Multivariate conditional logistic regression analysis was employed to identify clinical, sociodemographic and TB specific risk factors for recurrence. From a cohort of 4628 patients, 82 TB recurrences occurred (1.8%). Nineteen of 82 patients had paired isolates with MIRU-VNTR strain type profiles available, of which 84% were relapses and 16% reinfections. On multivariate analysis, smoking (OR 3.8; p = 0.04), grade 3/4 adverse drug reactions (OR 5.6; p = 0.02), ethnicity 'Indian subcontinent' (OR 8.5; p = <0.01), ethnicity 'other' (OR 31.2; p = 0.01) and receipt of immunosuppressants (OR 6.8; p = <0.01) were independent predictors of TB recurrence. Within this UK setting, the rate of TB recurrence was low, predominantly due to relapse. The identification of an elevated recurrence risk amongst the ethnic group contributing most cases to the national TB burden presents an opportunity to improve individual and population health.

Risperidone and Risk of Gynecomastia in Young Men.

PubMed

Etminan, Mahyar; Carleton, Bruce; Brophy, James M

2015-11-01

The purpose of this study was to quantify the risk of gynecomastia with risperidone in adolescent and young adult males. We created a cohort of males 15-25 years of age from the IMS LifeLink database, and conducted a case-control study within the cohort by identifying all new cases of gynecomastia. For each case, 10 controls were selected and matched to the cases by age, follow-up, and calendar times (cases and controls had the same follow up time and cohort entry date). Rate ratios (RR) for current use of risperidone were computed adjusting for potential confounding variables. First diagnosis of gynecomastia was made based on International Classification of Diseases, 9th revision (ICD-9) for gynecomastia. There were 401,924 males ages 15-25 in the primary cohort. There were 1556 cases of gynecomastia and 15,560 corresponding controls. Current users of risperidone had approximately four times the risk of developing gynecomastia than non-users (RR=3.91, 95% CI=2.01-7.62). When the analysis was stratified to children and adolescents (≤18 years of age) taking risperidone, the risk of gynecomastia was five times higher than for non-users (RR=5.44, 95% CI=1.50-19.74). Risperidone is associated with an increase with the risk of gynecomastia in adolescent and young adult males.

Case-control study of renal cell carcinoma in relation to occupation, smoking, and alcohol consumption

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brownson, R.C.

1988-05-01

A case-control study based on data from a cancer registry was conducted to evaluate the effects of smoking, alcohol use, and occupation on renal cell cancer risk. Information was obtained for 326 male and female cases and 978 age- and sex-matched controls. Elevated risks were identified for cigarette smokers and for men employed as truck drivers. No relationship between alcohol consumption and renal cancer was observed.

Clinical, virologic, and immunologic outcomes in lymphoma survivors and in cancer-free, HIV-1-infected patients: a matched cohort study.

PubMed

Spagnuolo, Vincenzo; Travi, Giovanna; Galli, Laura; Cossarini, Francesca; Guffanti, Monica; Gianotti, Nicola; Salpietro, Stefania; Lazzarin, Adriano; Castagna, Antonella

2013-08-01

The objective of this study was to compare immunologic, virologic, and clinical outcomes between living human immunodeficiency virus (HIV)-infected individuals who had a diagnosis of lymphoma versus outcomes in a control group of cancer-free, HIV-infected patients. In this matched cohort study, patients in the case group were survivors of incident lymphomas that occurred between 1997 and June 2010. Controls were living, cancer-free, HIV-infected patients who were matched to cases at a 4:1 ratio by age, sex, nadir CD4 cell count, and year of HIV diagnosis. The date of lymphoma diagnosis served as the baseline in cases and in the corresponding controls. In total, 62 patients (cases) who had lymphoma (20 with Hodgkin disease [HD] and 42 with non-Hodgkin lymphoma [NHL]) were compared with 211 controls. The overall median follow-up was 4.8 years (interquartile range, 2.0-7.9 years). The CD4 cell count at baseline was 278 cells/mm³ (interquartile range, 122-419 cells/mm³) in cases versus 421 cells/mm³ (interquartile range, 222-574 cells/mm³) in controls (P = .003). At the last available visit, the CD4 cell count was 412 cells/mm³ (range, 269-694 cells/mm³) in cases versus 518 cells/mm³ (interquartile range, 350-661 cells/mm³) in controls (P = .087). The proportion of patients who achieved virologic success increased from 30% at baseline to 74% at the last available visit in cases (P = .008) and from 51% to 81% in controls (P = .0286). Patients with HD reached higher CD4 cell counts at their last visit than patients with NHL (589 cells/mm³ [range, 400-841 cells/mm³] vs 332 cells/mm³ [interquartile range, 220-530 cells/mm³], respectively; P = .003). Virologic success was similar between patients with HD and patients with NHL at the last visit. Forty cases (65%) and 76 controls (36%) experienced at least 1 clinical event after baseline (P < .0001); cases were associated with a shorter time to occurrence of the first clinical event compared with controls (P < .0001). HIV-infected lymphoma survivors experienced more clinical events than controls, especially during the first year of follow-up, but they reached similar long-term immunologic and virologic outcomes. © 2013 American Cancer Society.

Risk factors and mortality for nosocomial bloodstream infections in elderly patients.

PubMed

Reunes, S; Rombaut, V; Vogelaers, D; Brusselaers, N; Lizy, C; Cankurtaran, M; Labeau, S; Petrovic, M; Blot, S

2011-10-01

To determine risk factors for nosocomial bloodstream infection (BSI) and associated mortality in geriatric patients in geriatric and internal medicine wards at a university hospital. Single-center retrospective (1992-2007), pairwise-matched (1:1-ratio) cohort study. Geriatric patients with nosocomial BSI were matched with controls without BSI on year of admission and length of hospitalization before onset of BSI. Demographic, microbiological, and clinical data are collected. One-hundred forty-two BSI occurred in 129 patients. Predominant microorganisms were Escherichia coli (23.2%), coagulase-negative Staphylococci (19.4%), Pseudomonas aeruginosa (8.4%), Staphylococcus aureus (7.1%), Klebsiella pneumoniae (5.8%) and Candida spp. (5.8%). Matching was successful for 109 cases. Compared to matched control subjects, cases were more frequently female, suffered more frequently from arthrosis, angina pectoris and pressure ulcers, had worse Activities of Daily Living-scores, had more often an intravenous or bladder catheter, and were more often bedridden. Logistic regression demonstrated presence of an intravenous catheter (odds ratio [OR] 7.5, 95% confidence interval [CI] 2.5-22.9) and being bedridden (OR 2.9, 95% CI 1.6-5.3) as independent risk factors for BSI. In univariate analysis nosocomial BSI was associated with increased mortality (22.0% vs. 11.0%; P=0.029). After adjustment for confounding co-variates, however, nosocomial BSI was not associated with mortality (hazard ratio 1.3, 95% CI 0.6-2.6). Being bedridden and increasing age were independent risk factors for death. Intravenous catheters and being bedridden are the main risk factors for nosocomial BSI. Although associated with higher mortality, this infectious complication seems not to be an independent risk factor for death in geriatric patients. Copyright © 2011 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.

Do differences in female sex hormone levels contribute to gastro-oesophageal reflux disease?

PubMed

Menon, Shyam; Prew, Sandra; Parkes, Gill; Evans, Stephanie; Smith, Lynne; Nightingale, Peter; Trudgill, Nigel

2013-07-01

Hormone replacement therapy is associated with both reflux symptoms and oesophagitis. During pregnancy, elevated sex hormones are thought to contribute to the high prevalence of reflux symptoms. Increased female sex hormone levels may thus contribute to the aetiology of gastro-oesophageal reflux disease (GORD). To determine if female sex hormone levels are associated with symptomatic acid reflux. Women with GORD symptoms undergoing oesophageal pH monitoring were prospectively recruited. 'Cases' and 'controls' were defined by normal and excess total acid exposure on pH monitoring and were age-matched and BMI-matched. Case and control groups were further stratified into premenopausal and postmenopausal groups. Demographic data were collected, body morphological parameters were measured and oestradiol, oestrone, progesterone and sex hormone-binding globulin were measured. One hundred and twenty-one women [mean age 52 (SD 11.6) years] were recruited and 104 [mean age 51 (SD 11.6) years] were matched for age and BMI. Increasing BMI, as expected, correlated with increasing acid exposure [premenopausal (r=0.404, P=0.02), postmenopausal (r=0.401, P=0.01)]. Increasing BMI also correlated with sex hormone levels [premenopausal oestradiol (r=0.52, P=0.004), postmenopausal oestrone (r=0.364, P=0.01)]. In premenopausal women, sex hormone binding globulin (r=-0.27, P=0.05) and testosterone (r=0.29, P=0.05) correlated with increasing acid exposure, but oestradiol fell just short of significance (r=0.26, P=0.06). However, on matching for BMI, no association between sex hormones and increased acid exposure on pH monitoring was found on multivariate logistic regression analysis. Female sex hormone levels do not appear to contribute to GORD, once adjustment is made for the influence of increasing BMI.

Factors Associated with Injuries among Commercial Motorcyclists: Evidence from a Matched Case Control Study in Kampala City, Uganda

PubMed Central

Tumwesigye, Nazarius M.; Atuyambe, Lynn M.; Kobusingye, Olive K.

2016-01-01

Introduction Road traffic injuries are the eighth leading cause of death globally and the most affected are young people aged 15–29. By 2030 road traffic deaths will become the fifth leading cause of death unless urgent action is taken. Motorcyclists are among the most vulnerable road users and in Uganda they contribute 41% of all road traffic injuries. This paper establishes factors associated with the injuries of commercial motorcycle riders also known as boda-boda riders in Kampala, Uganda’s capital city. Methods The study was matched case-control with a case being a boda-boda rider that was seen at one of the 5 major city hospitals with a road traffic injury while a control was a boda-boda rider that was at the parking stage where the case operated from before the injury. The sample size was 289 riders per arm and data collection took 7 months. A structured questionnaire was used to collect data on background and exposing factors. Being matched case-control data conditional logistic regression was used in the analysis. Results Factors independently associated with injury among motorcyclists were younger age group, being a current alcohol drinker (OR = 2.30, 95%CI: 1.19–4.45), lower engine capacity (<100cc)(OR = 5.03, 95%CI: 2.91–8.70), riding experience of less than 3 years, not changing a motorcycle in past 1 year (OR = 2.04, 95%CI: 1.19–3.52), riding for a longer time in a day (OR = 6.05, 95%CI: 2.58–14.18) and sharing a motorcycle (OR = 8.25, 95%CI:2.62–25.9). Other factors associated with injury were low level of knowledge of traffic rules, being stopped by police for checks on condition of motorcycle/license/insurance, working till late. Recommendations More road safety sensitization is required among riders to raise awareness against sharing motorcycles, working for a longer time and alcohol consumption. Police enforcement of drink-driving laws should include riders of commercial motorcycles. Investigate the validity of motorcycle riding licenses and test the riding competency of all who got licenses in last 3 years. PMID:26918871

Does functional vision behave differently in low-vision patients with diabetic retinopathy?--A case-matched study.

PubMed

Ahmadian, Lohrasb; Massof, Robert

2008-09-01

A retrospective case-matched study designed to compare patients with diabetic retinopathy (DR) and other ocular diseases, managed in a low-vision clinic, in four different types of functional vision. Reading, mobility, visual motor, and visual information processing were measured in the patients (n = 114) and compared with those in patients with other ocular diseases (n = 114) matched in sex, visual acuity (VA), general health status, and age, using the Activity Inventory as a Rasch-scaled measurement tool. Binocular distance visual acuity was categorized as normal (20/12.5-20/25), near normal (20/32-20/63), moderate (20/80-20/160), severe (20/200-20/400), profound (20/500-20/1000), and total blindness (20/1250 to no light perception). Both Wilcoxon matched pairs signed rank test and the sign test of matched pairs were used to compare estimated functional vision measures between DR cases and controls. Cases ranged in age from 19 to 90 years (mean age, 67.5), and 59% were women. The mean visual acuity (logMar scale) was 0.7. Based on the Wilcoxon signed rank test analyses and after adjusting the probability for multiple comparisons, there was no statistically significant difference (P > 0.05) between patients with DR and control subjects in any of four functional visions. Furthermore, diabetic retinopathy patients did not differ (P > 0.05) from their matched counterparts in goal-level vision-related functional ability and total visual ability. Visual impairment in patients with DR appears to be a generic and non-disease-specific outcome that can be explained mainly by the end impact of the disease in the patients' daily lives and not by the unique disease process that results in the visual impairment.

Worker substance use, workplace problems and the risk of occupational injury: a matched case-control study.

PubMed

Spicer, Rebecca S; Miller, Ted R; Smith, Gordon S

2003-07-01

This study examines the tendency toward problem behavior as an explanation for the relationship between problem substance use and occupational injury. The authors used a matched case-control study nested in a cohort of 26,413 workers, in which cases (n = 3,994) were workers suffering an occupational injury. Five controls per case (n = 19,970) were selected from the cohort of workers active on the day of the injury and matched on job type. Conditional logistic regression modeled the association of problem substance use with occupational injury, controlling for problem behaviors and worker characteristics. Problem substance use was indicated indirectly if any of the following were alcohol/drug-involved during the comparison period: Employee Assistance Program visit, excused absence or disciplinary action. Discipline records identified minor (absenteeism) and serious (dishonesty, theft, assault, harassment, disrespect) problem behaviors during the comparison period. The odds of injury among workers with an indicator of problem substance use was 1.35 (p = .015) times greater than the odds among workers without an indicator, controlling for job type and demographics as well as adjusting for exposure. This ratio declined to 1.21 (p = .138) when problem behaviors were also controlled for. Minor and serious problem behaviors were significantly associated with occupational injury (odds ratio [OR] = 1.73, p < .001, and OR = 2.19, p < .001, respectively), controlling for demographics and substance use. The relationship of problem substance use with occupational injury was weak when problem behaviors were controlled for, suggesting that this relationship, observed in previous studies, may be explained by a workers tendency toward problem behaviors. Workplace injury prevention programs should address the expression of problem behaviors as a complement to drug and alcohol deterrent programs.

Rate of return to pitching and performance after Tommy John surgery in Major League Baseball pitchers.

PubMed

Erickson, Brandon J; Gupta, Anil K; Harris, Joshua D; Bush-Joseph, Charles; Bach, Bernard R; Abrams, Geoffrey D; San Juan, Angielyn M; Cole, Brian J; Romeo, Anthony A

2014-03-01

Medial ulnar collateral ligament (UCL) reconstruction is a common procedure performed on Major League Baseball (MLB) pitchers in the United States. To determine (1) the rate of return to pitching (RTP) in the MLB after UCL reconstruction, (2) the RTP rate in either the MLB and minor league combined, (3) performance after RTP, and (4) the difference in the RTP rate and performance between pitchers who underwent UCL reconstruction and matched controls without UCL injuries. Cohort study; Level of evidence, 3. Major League Baseball pitchers with symptomatic medial UCL deficiency who underwent UCL reconstruction were evaluated. All player, elbow, and surgical demographic data were analyzed. Controls matched by age, body mass index, position, handedness, and MLB experience and performance were selected from the MLB during the same years as those undergoing UCL reconstruction. An "index year" was designated for controls, analogous to the UCL reconstruction year in cases. Return to pitching and performance measures in the MLB were compared between cases and controls. Student t tests were performed for analysis of within-group and between-group variables, respectively. A total of 179 pitchers with UCL tears who underwent reconstruction met the inclusion criteria and were analyzed. Of these, 148 pitchers (83%) were able to RTP in the MLB, and 174 pitchers were able to RTP in the MLB and minor league combined (97.2%), while only 5 pitchers (2.8%) were never able to RTP in either the MLB or minor league. Pitchers returned to the MLB at a mean 20.5 ± 9.72 months after UCL reconstruction. The length of career in the MLB after UCL reconstruction was 3.9 ± 2.84 years, although 56 of these patients were still currently actively pitching in the MLB at the start of the 2013 season. The revision rate was 3.9%. In the year before UCL reconstruction, pitching performance declined significantly in the cases versus controls in the number of innings pitched, games played, and wins and the winning percentage (P < .05). After surgery, pitchers showed significantly improved performance versus before surgery (fewer losses, a lower losing percentage, lower earned run average [ERA], threw fewer walks, and allowed fewer hits, runs, and home runs) (P < .05). Comparisons between cases and controls for the time frame after UCL reconstruction (cases) or the index year (controls) demonstrated that cases had significantly (P < .05) fewer losses per season and a lower losing percentage. In addition, cases had a significantly lower ERA and allowed fewer walks and hits per inning pitched. There is a high rate of RTP in professional baseball after UCL reconstruction. Performance declined before surgery and improved after surgery. When compared with demographic-matched controls, patients who underwent UCL reconstruction had better results in multiple performance measures. Reconstruction of the UCL allows for a predictable and successful return to the MLB.

The impact of type 2 diabetes on health related quality of life in Bangladesh: results from a matched study comparing treated cases with non-diabetic controls.

PubMed

Safita, Novie; Islam, Sheikh Mohammed Shariful; Chow, Clara K; Niessen, Louis; Lechner, Andreas; Holle, Rolf; Laxy, Michael

2016-09-13

Little is known about the association between diabetes and health related quality of life (HRQL) in lower-middle income countries. This study aimed to investigate HRQL among individuals with and without diabetes in Bangladesh. The analysis is based on data of a case-control study, including 591 patients with type 2 diabetes (cases) who attended an outpatient unit of a hospital in Dhaka and 591 age -and sex-matched individuals without diabetes (controls). Information about socio-demographic characteristics, health conditions, and HRQL were assessed in a structured interview. HRQL was measured with the EuroQol (EQ) visual analogue scale (VAS) and the EQ five-dimensional (5D) descriptive system. The association between diabetes status and quality of life was examined using multiple linear and logistic regression models. Mean EQ-VAS score of patients with diabetes was 11.5 points lower (95 %-CI: -13.5, -9.6) compared to controls without diabetes. Patients with diabetes were more likely to report problems in all EQ-5D dimensions than controls, with the largest effect observed in the dimensions 'self-care' (OR = 5.9; 95 %-CI: 2.9, 11.8) and 'mobility' (OR = 4.5; 95 %-CI: 3.0, -6.6). In patients with diabetes, male gender, high education, and high-income were associated with higher VAS score and diabetes duration and foot ulcer associated with lower VAS scores. Other diabetes-related complications were not significantly associated with HRQL. Our findings suggest that the impact of diabetes on HRQL in the Bangladeshi population is much higher than what is known from western populations and that unlike in western populations comorbidities/complications are not the driving factor for this effect.

Mid-Season Influenza Vaccine Effectiveness Estimates for the 2016-2017 Influenza Season (Open Access Publisher’s Version)

DTIC Science & Technology

2017-08-01

controls ; AFHSB used healthy controls (matched to cases by sex, age, date [+/– 3 days] and location). bAFHSB-AF adjusted for age group , month of illness...presented in this report. M E T H O D S The AFHSB–Air Force Satellite Cell (AFHSB-AF) conducted a test-negative case- control study using data from the...ILI). Influenza cases were identified using reverse transcription–polymerase chain reaction (RT-PCR) or viral culture; controls were ILI patients

Early mortality and morbidity after total hip arthroplasty in patients with femoral neck fracture

PubMed Central

Hailer, Nils P; Garland, Anne; Rogmark, Cecilia; Garellick, Göran; Kärrholm, Johan

2016-01-01

Background and purpose — Early postoperative mortality is relatively high after total hip arthroplasty (THA) that has been performed due to femoral neck fracture. However, this has rarely been investigated after adjustment for medical comorbidity and comparison with the mortality in an age-matched population. We therefore assessed early mortality in hip fracture patients treated with a THA, in the setting of a nationwide matched cohort study. Patients and methods — 24,699 patients who underwent THA due to a femoral neck fracture between 1992 and 2012 were matched with 118,518 controls. Kaplan-Meier survival analysis was used to calculate cumulative unadjusted survival, and Cox regression models were fitted to compute hazard ratios (HRs) and 95% confidence intervals (CIs), with adjustment for age, sex, comorbidity, and socioeconomic background. Results — 90-day survival was 96.3% (95% CI: 96.0–96.5) for THA cases and 98.7% (95% CI: 98.6–98.8) for control individuals, giving an adjusted HR of 2.2 (95% CI: 2.0–2.4) for THA cases compared to control individuals. Comorbidity burden increased in THA cases over time, but the adjusted risk of death within 90 days did not differ statistically significantly between the time periods investigated (1992–1998, 1999–2005, and 2006–2012). A Charlson comorbidity index of 3 or more, an American Society of Anesthesiologists (ASA) grade of 3 and above, male sex, an age of 80 years and above, an income below the first quartile, and a lower level of education were all associated with an increased risk of 90-day mortality. Interpretation — The adjusted early mortality in femoral neck fracture patients who underwent THA was about double that in a matched control population. Patients with femoral neck fracture but with no substantial comorbidity and an age of less than 80 years appear to have a low risk of early death. Patients older than 80 years and those with a Charlson comorbidity index of more than 2 have a high risk of early death, and such patients would perhaps benefit from treatment strategies other than THA, but this should be investigated further. PMID:27649030

Blood-Based Biomarkers of Early-Onset Breast Cancer

DTIC Science & Technology

2015-10-01

n=51). The women with early-onset breast cancer were disease and treatment free for at least 6 months at time of blood donation . Cases and controls...were age matched to age at blood donation . 2. KEYWORDS: biomarkers, early-onset breast cancer, expression profiling, risk-assessment, breast cancer...matched controls. This prospectively collected cohort consists of blood donated to blood banks ~15 years ago and subsequently linked to the California

Risk factors in lateral epicondylitis (tennis elbow): a case-control study.

PubMed

Titchener, A G; Fakis, A; Tambe, A A; Smith, C; Hubbard, R B; Clark, D I

2013-02-01

Lateral epicondylitis is a common condition, but relatively little is known about its aetiology and associated risk factors. We have undertaken a large case-control study using The Health Improvement Network database to assess and quantify the relative contributions of some constitutional and environmental risk factors for lateral epicondylitis in the community. Our dataset included 4998 patients with lateral epicondylitis who were individually matched with a single control by age, sex, and general practice. The median age at diagnosis was 49 (interquartile range 42-56) years . Multivariate analysis showed that the risk factors associated with lateral epicondylitis were rotator cuff pathology (OR 4.95), De Quervain's disease (OR 2.48), carpal tunnel syndrome (OR 1.50), oral corticosteroid therapy (OR 1.68), and previous smoking history (OR 1.20). Diabetes mellitus, current smoking, trigger finger, rheumatoid arthritis, alcohol intake, and obesity were not found to be associated with lateral epicondylitis.

Toxoplasma gondii exposure and epilepsy: A matched case-control study in a public hospital in northern Mexico.

PubMed

Alvarado-Esquivel, Cosme; Rico-Almochantaf, Yazmin Del Rosario; Hernández-Tinoco, Jesús; Quiñones-Canales, Gerardo; Sánchez-Anguiano, Luis Francisco; Torres-González, Jorge; Ramírez-Valles, Eda Guadalupe; Minjarez-Veloz, Andrea

2018-01-01

This study aimed to determine the association between infection with Toxoplasma gondii and epilepsy in patients attended to in a public hospital in the northern Mexican city of Durango. We performed an age- and gender-matched case-control study of 99 patients suffering from epilepsy and 99 without epilepsy. Sera of participants were analyzed for anti- T. gondii IgG and IgM antibodies using commercially available enzyme-linked immunoassays. Seropositive samples to T. gondii were further analyzed for detection of T. gondii DNA by polymerase chain reaction. Anti- T. gondii IgG antibodies were found in 10 (10.1%) of the 99 cases and in 6 (6.1%) of the 99 controls (odds ratio = 1.74; 95% confidence interval: 0.60-4.99; p = 0.43). High (> 150 IU/mL) levels of anti- T. gondii IgG antibodies were found in 6 of the 99 cases and in 4 of the 99 controls (odds ratio = 1.53; 95% confidence interval: 0.41-5.60; p = 0.74). Anti- T. gondii IgM antibodies were found in 2 of the 10 IgG seropositive cases, and in 2 of the 6 IgG seropositive controls (odds ratio = 0.50; 95% confidence interval: 0.05-4.97; p = 0.60). T. gondii DNA was not found in any of the 10 anti- T. gondii IgG positive patients. Bivariate analysis of IgG seropositivity to T. gondii and International Statistical Classification of Diseases and related Health Problems, 10th Edition codes of epilepsy showed an association between seropositivity and G40.1 code (odds ratio = 22.0; 95% confidence interval: 2.59-186.5; p = 0.008). Logistic regression analysis showed an association between T. gondii infection and consumption of goat meat (odds ratio = 6.5; 95% confidence interval: 1.22-34.64; p = 0.02), unwashed raw vegetables (odds ratio = 26.3; 95% confidence interval: 2.61-265.23; p = 0.006), and tobacco use (odds ratio = 6.2; 95% confidence interval: 1.06-36.66; p = 0.04). Results suggest that T. gondii infection does not increase the risk of epilepsy in our setting; however, infection might be linked to specific types of epilepsy. Factors associated with T. gondii infection found in this study may aid in the design of preventive measures against toxoplasmosis.

Point process methods in epidemiology: application to the analysis of human immunodeficiency virus/acquired immunodeficiency syndrome mortality in urban areas.

PubMed

Quesada, Jose Antonio; Melchor, Inmaculada; Nolasco, Andreu

2017-05-26

The analysis of spatio-temporal patterns of disease or death in urban areas has been developed mainly from the ecological studies approach. These designs may have some limitations like the ecological fallacy and instability with few cases. The objective of this study was to apply the point process methodology, as a complement to that of aggregated data, to study HIV/AIDS mortality in men in the city of Alicante (Spain). A case-control study in residents in the city during the period 2004-2011 was designed. Cases were men who died from HIV/AIDS and controls represented the general population, matched by age to cases. The risk surfaces of death over the city were estimated using the log-risk function of intensities, and we contrasted their temporal variations over the two periods. High risk significant areas of death by HIV/AIDS, which coincide with the most deprived areas in the city, were detected. Significant spatial change of the areas at risk between the periods studied was not detected. The point process methodology is a useful tool to analyse the patterns of death by HIV/AIDS in urban areas.

Risk factors for the occurrence of sporadic Salmonella enterica serotype enteritidis infections in children in France: a national case-control study.

PubMed Central

Delarocque-Astagneau, E.; Desenclos, J. C.; Bouvet, P.; Grimont, P. A.

1998-01-01

To determine risk factors associated with the occurrence of sporadic cases of Salmonella enteritidis infections among children in France, we conducted a matched case-control study. Cases were identified between 1 March and 30 September 1995. One hundred and five pairs of cases and controls matched for age and place of residence were interviewed. In the 1-5 years age group, illness was associated with the consumption of raw eggs or undercooked egg-containing foods (OR 2.4, 95% CI 1.2-4.8). Storing eggs more than 2 weeks after purchase was associated with Salmonella enteritidis infection (OR 3.8, 95% CI 1.4-10.2), particularly during the summer period (OR 6.0, 95% CI 1.3-26.8). Cases were more likely to report a case of diarrhoea in the household 10-3 days before the onset of symptoms, particularly in the age group < or = 1 year (P = 0.01). This study confirms the link between eggs and the occurrence of sporadic cases of Salmonella enteritidis among children, highlights the potential role of prolonged egg storage and underlines the role of person-to-person transmission in infants. PMID:10030705

HIV infection among U.S. Army and Air Force military personnel: sociodemographic and genotyping analysis.

PubMed

Singer, Darrell E; Bautista, Christian T; O'Connell, Robert J; Sanders-Buell, Eric; Agan, Brian K; Kijak, Gustavo H; Hakre, Shilpa; Sanchez, Jose L; Sateren, Warren B; McCutchan, Francine E; Michael, Nelson L; Scott, Paul T

2010-08-01

Since 1985, the U.S. Department of Defense has periodically screened all military personnel for HIV allowing for the monitoring of the infection in this dynamic cohort population. A nested case-control study was performed to study sociodemographics, overseas assignment, and molecular analysis of HIV. Cases were newly identified HIV infections among U.S. Army and Air Force military personnel from 2000 to 2004. Controls were frequency matched to cases by gender and date of case first positive HIV screening test. Genotyping analysis was performed using high-throughput screening assays and partial genome sequencing. HIV was significantly associated with black race [odds ratio (OR) = 6.65], single marital status (OR = 4.45), and age (OR per year = 1.07). Ninety-seven percent were subtype B and 3% were non-B subtypes (A3, CRF01_AE, A/C recombinant, G, CRF02_AG). Among cases, overseas assignment in the period at risk prior to their first HIV-positive test was associated with non-B HIV subtype infection (OR = 8.44). Black and single military personnel remain disproportionately affected by HIV infection. Most non-B HIV subtypes were associated with overseas assignment. Given the increased frequency and length of assignments, and the expanding HIV genetic diversity observed in this population, there is a need for active HIV genotyping surveillance and a need to reinforce primary HIV prevention efforts.

The Ukrainian-American Study of Leukemia and Related Disorders Among Chornobyl Cleanup Workers from Ukraine: I. STUDY METHODS

PubMed Central

Romanenko, A.; Bebeshko, V; Hatch, M; Bazyka, D; Finch, S.; Dyagil, I; Reiss, R.; Chumak, V; Bouville, A; Gudzenko, N; Zablotska, L; Pilinskaya, M.; Lyubarets, T.; Bakhanova, E.; Babkina, N.; Trotsiuk, N.; Ledoschuk, B.; Belayev, Y.; Dybsky, S.S.; Ron, E.; Howe, G.

2010-01-01

Thus far there are relatively few data on the risk of leukemia among those who were exposed to external radiation during cleanup operations following the Chornobyl nuclear accident, and results have not been consistent. To investigate this issue further, we assembled a cohort of 110,645 male cleanup workers from Ukraine and identified cases of leukemia occurring during the period 1986 to 2000. Detailed interviews were conducted and individual bone marrow doses were estimated using a new time-and-motion method known as RADRUE (Realistic Analytical Dose Reconstruction with Uncertainty Estimate). See companion paper II for a detailed description of the dosimetry. For the initial analyses we used a nested case-control approach with a minimum of five controls per case, matched for year of birth, oblast (region) of registration and residence. All identified cases were reviewed by an international panel of experts. The dose-response analysis and results are given in companion paper III. PMID:19138036

Population versus hospital controls in the assessment of dietary intake of isoflavone for case-control studies on cancers in China.

PubMed

Li, Lin; Zhang, Min; Holman, C D'Arcy J

2013-01-01

To assess dietary isoflavone intake between population and hospital outpatient controls and examine if cancer risks estimated for isoflavone using hospital outpatient controls would be different from those using population controls. Three parallel case-control studies on leukemia, breast, and colorectal cancers in China in 2009-2010 were conducted, using population and hospital outpatient controls to separately match 560 incident cases at a 1:1 ratio. A validated food frequency questionnaire was administered by face-to-face interview. Conditional logistic regression analysis was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). The 2 control groups had closely similar distributions of dietary isoflavone intake. Risk estimates for breast cancers were adjusted ORs (95% CI) of 0.39 (0.23-0.66) and 0.31 (0.18-0.55) for daidzein, 0.35 (0.20-0.61) and 0.28 (0.16-0.52) for genistein, 0.66 (0.41-1.08) and 0.53 (0.32-0.88) for glycitein, and 0.53 (0.33-0.85) and 0.43 (0.26-0.71) for total isoflavone using hospital outpatient and population controls respectively. The study found that hospital outpatient controls were comparable to population controls in measured dietary intake of isoflavone in the Chinese hospital setting.

Impact of diabetes on healthcare costs in a population-based cohort: a cost analysis.

PubMed

Rosella, L C; Lebenbaum, M; Fitzpatrick, T; O'Reilly, D; Wang, J; Booth, G L; Stukel, T A; Wodchis, W P

2016-03-01

To estimate the healthcare costs attributable to diabetes in Ontario, Canada using a propensity-matched control design and health administrative data from the perspective of a single-payer healthcare system. Incident diabetes cases among adults in Ontario were identified from the Ontario Diabetes Database between 2004 and 2012 and matched 1:3 to control subjects without diabetes identified in health administrative databases on the basis of sociodemographics and propensity score. Using a comprehensive source of administrative databases, direct per-person costs (Canadian dollars 2012) were calculated. A cost analysis was performed to calculate the attributable costs of diabetes; i.e. the difference of costs between patients with diabetes and control subjects without diabetes. The study sample included 699 042 incident diabetes cases. The costs attributable to diabetes were greatest in the year after diagnosis [C$3,785 (95% CI 3708, 3862) per person for women and C$3,826 (95% CI 3751, 3901) for men], increasing substantially for older age groups and patients who died during follow-up. After accounting for baseline comorbidities, attributable costs were primarily incurred through inpatient acute hospitalizations, physician visits and prescription medications and assistive devices. The excess healthcare costs attributable to diabetes are substantial and pose a significant clinical and public health challenge. This burden is an important consideration for decision-makers, particularly given increasing concern over the sustainability of the healthcare system, aging population structure and increasing prevalence of diabetic risk factors, such as obesity. © 2015 The Authors. Diabetic Medicine published by John Wiley & Sons Ltd on behalf of Diabetes UK.

Risk of neuroblastoma, birth-related characteristics, congenital malformations and perinatal exposures: A pooled analysis of the ESCALE and ESTELLE French studies (SFCE).

PubMed

Rios, Paula; Bailey, Helen D; Orsi, Laurent; Lacour, Brigitte; Valteau-Couanet, Dominique; Levy, Dominique; Corradini, Nadège; Leverger, Guy; Defachelles, Anne-Sophie; Gambart, Marion; Sirvent, Nicolas; Thebaud, Estelle; Ducassou, Stéphane; Clavel, Jacqueline

2016-11-01

Neuroblastoma (NB), an embryonic tumour arising from neural crest cells, is the most common malignancy among infants. The aetiology of NB is largely unknown. We conducted a pooled analysis to explore whether there is an association between NB and preconception and perinatal factors using data from two French national population-based case-control studies. The mothers of 357 NB cases and 1783 controls younger than 6 years, frequency-matched by age and gender, responded to a telephone interview that focused on demographic, socioeconomic and perinatal characteristics, childhood environment, life-style and maternal reproductive history. Unconditional logistic regression was used to estimate pooled odds ratios and 95% confidence intervals. After controlling for matching variables, study of origin and potential confounders, being born either small (OR 1.4 95% CI 1.0-2.0) or large (OR 1.5 95% CI 1.1-2.2) for gestational age and, among children younger than 18 months, having congenital malformations (OR 3.6 95% CI 1.3-8.9), were significantly associated with NB. Inverse associations were observed with breastfeeding (OR 0.7 95% CI 0.5-1.0) and maternal use of any supplements containing folic acid, vitamins or minerals (OR 0.5 95% CI 0.3-0.9) during the preconception period. Our findings reinforce the hypothesis that fetal growth anomalies and congenital malformations may be associated with an increased risk of NB. Further investigations are needed in order to clarify the role of folic acid supplementation and breastfeeding, given their potential importance in NB prevention. © 2016 UICC.

Platelet aggregation inhibitors, vitamin K antagonists and risk of subarachnoid hemorrhage.

PubMed

Risselada, R; Straatman, H; van Kooten, F; Dippel, D W J; van der Lugt, A; Niessen, W J; Firouzian, A; Herings, R M C; Sturkenboom, M C J M

2011-03-01

Use of platelet aggregation inhibitors and vitamin K antagonists has been associated with an increased risk of intracranial hemorrhage (ICH). Whether the use of these antithrombotic drugs is associated with an increased risk of subarachnoid hemorrhage (SAH) remains unclear, especially as confounding by indication might play a role. The aim of the present study was to investigate whether use of platelet aggregation inhibitors or vitamin K antagonists increase the risk of SAH. We applied population-based case-control, case-crossover and case-time-control designs to estimate the risk of SAH while addressing issues both of confounding by indication and time varying exposure within the PHARMO Record Linkage System database. This system includes drug dispensing records from community pharmacies and hospital discharge records of more than 3 million community-dwelling inhabitants in the Netherlands. Patients were considered a case if they were hospitalized for a first SAH (ICD-9-CM code 430) in the period between 1st January 1998 and 31st December 2006. Controls were selected from the source population, matched on age, gender and date of hospitalization. Conditional logistic regression was used to estimate multivariable adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for the risk of SAH during use of platelet aggregation inhibitors or vitamin K antagonists. In the case-crossover and case-time-control designs we selected 11 control periods preceding the index date in successive steps of 1 month in the past. In all, 1004 cases of SAH were identified. In the case-control analysis the adjusted OR for the risk of SAH in current use of platelet aggregation inhibitors was 1.32 (95% CI: 1.02-1.70) and in current use of vitamin K antagonists 1.29 (95% CI: 0.89-1.87) compared with no use. In the case-crossover analysis the ORs for the risk of SAH in current use of platelet aggregation inhibitors and vitamin K antagonists were 1.04 (95% CI: 0.56-1.94) and 2.46 (95% CI: 1.04-5.82), respectively. In the case-time-control analysis the OR for platelet aggregation inhibitors was 0.50 (95% CI: 0.26-0.98) and for vitamin K antagonists 1.98 (95% CI: 0.82-4.76). The use of platelet aggregation inhibitors was not associated with an increased SAH risk; the modest increase observed in the case-control analysis could be as a result of confounding. The use of vitamin K antagonists seemed to be associated with an increased risk of SAH. The increase was most pronounced in the case-crossover analysis and therefore cannot be explained by unmeasured confounding. © 2011 International Society on Thrombosis and Haemostasis.

Lung Cancer Risk Among Hairdressers: A Pooled Analysis of Case-Control Studies Conducted Between 1985 and 2010

PubMed Central

Olsson, Ann C.; Xu, Yiwen; Schüz, Joachim; Vlaanderen, Jelle; Kromhout, Hans; Vermeulen, Roel; Peters, Susan; Stücker, Isabelle; Guida, Florence; Brüske, Irene; Wichmann, Heinz-Erich; Consonni, Dario; Landi, Maria Teresa; Caporaso, Neil; Tse, Lap Ah; Yu, Ignatius Tak-sun; Siemiatycki, Jack; Richardson, Lesley; Mirabelli, Dario; Richiardi, Lorenzo; Simonato, Lorenzo; Gustavsson, Per; Plato, Nils; Jöckel, Karl-Heinz; Ahrens, Wolfgang; Pohlabeln, Hermann; Tardón, Adonina; Zaridze, David; Marcus, Michael W.; ‘t Mannetje, Andrea; Pearce, Neil; McLaughlin, John; Demers, Paul; Szeszenia-Dabrowska, Neonila; Lissowska, Jolanta; Rudnai, Peter; Fabianova, Eleonora; Dumitru, Rodica Stanescu; Bencko, Vladimir; Foretova, Lenka; Janout, Vladimir; Boffetta, Paolo; Fortes, Cristina; Bueno-de-Mesquita, Bas; Kendzia, Benjamin; Behrens, Thomas; Pesch, Beate; Brüning, Thomas; Straif, Kurt

2013-01-01

Increased lung cancer risks among hairdressers were observed in large registry-based cohort studies from Scandinavia, but these studies could not adjust for smoking. Our objective was to evaluate the lung cancer risk among hairdressers while adjusting for smoking and other confounders in a pooled database of 16 case-control studies conducted in Europe, Canada, China, and New Zealand between 1985 and 2010 (the Pooled Analysis of Case-Control Studies on the Joint Effects of Occupational Carcinogens in the Development of Lung Cancer). Lifetime occupational and smoking information was collected through interviews with 19,369 cases of lung cancer and 23,674 matched population or hospital controls. Overall, 170 cases and 167 controls had ever worked as hairdresser or barber. The odds ratios for lung cancer in women were 1.65 (95% confidence interval (CI): 1.16, 2.35) without adjustment for smoking and 1.12 (95% CI: 0.75, 1.68) with adjustment for smoking; however, women employed before 1954 also experienced an increased lung cancer risk after adjustment for smoking (odds ratio = 2.66, 95% CI: 1.09, 6.47). The odds ratios in male hairdressers/barbers were generally not elevated, except for an increased odds ratio for adenocarcinoma in long-term barbers (odds ratio = 2.20, 95% CI: 1.02, 4.77). Our results suggest that the increased lung cancer risks among hairdressers are due to their smoking behavior; single elevated risk estimates should be interpreted with caution and need replication in other studies. PMID:24068200

[Shigellosis outbreak with 146 cases related to a fair].

PubMed

Castell Monsalve, Juan; Gutiérrez Avila, Gonzalo; Rodolfo Saavedra, Remedios; Santos Azorín, Antonia

2008-01-01

On September 3, 2005, the Ciudad Real Public Health Service (Spain) received a report of 20 cases of gastroenteritis in the municipality of Daimiel. We conducted an investigation to determine the cause or causes of the outbreak and to implement control measures. Most of the cases involved young people who visited the municipality's fair. We carried out a descriptive study and an analytic case-control study. In the descriptive study, all variables of interest available in the medical records were included. In the case-control study, each case was matched with a control by age (plus or minus 5 years), gender, and attendance at the fair. Sixty-five cases and 65 controls were finally included in the study. Samples of foods and stools from food handlers were taken. We found 196 cases, 146 of which were confirmed. The epidemic curve suggested a common source of infection with a short period of activity. The case-control study showed an association between infection and eating potatoes with a sauce at any of the fair's five food stalls (OR = 20.56; 95%CI, 6.15-75.93; p < 0.0001). Logistic regression analysis showed an association with eating potatoes in food stall number 2 (OR = 6.38; 95%CI, 1.70-23.90; p < 0.0059). Neither samples of foods nor stools from food handlers yielded any positive results. However, Shigella sonnei was isolated from stool samples from 20 cases. The epidemiological study suggested that the most probable cause of the outbreak was a sauce, handmade with garlic, milk, and oil and served with the potatoes.

2013 multistate outbreaks of Cyclospora cayetanensis infections associated with fresh produce: focus on the Texas investigations.

PubMed

Abanyie, F; Harvey, R R; Harris, J R; Wiegand, R E; Gaul, L; Desvignes-Kendrick, M; Irvin, K; Williams, I; Hall, R L; Herwaldt, B; Gray, E B; Qvarnstrom, Y; Wise, M E; Cantu, V; Cantey, P T; Bosch, S; DA Silva, A J; Fields, A; Bishop, H; Wellman, A; Beal, J; Wilson, N; Fiore, A E; Tauxe, R; Lance, S; Slutsker, L; Parise, M

2015-12-01

The 2013 multistate outbreaks contributed to the largest annual number of reported US cases of cyclosporiasis since 1997. In this paper we focus on investigations in Texas. We defined an outbreak-associated case as laboratory-confirmed cyclosporiasis in a person with illness onset between 1 June and 31 August 2013, with no history of international travel in the previous 14 days. Epidemiological, environmental, and traceback investigations were conducted. Of the 631 cases reported in the multistate outbreaks, Texas reported the greatest number of cases, 270 (43%). More than 70 clusters were identified in Texas, four of which were further investigated. One restaurant-associated cluster of 25 case-patients was selected for a case-control study. Consumption of cilantro was most strongly associated with illness on meal date-matched analysis (matched odds ratio 19·8, 95% confidence interval 4·0-∞). All case-patients in the other three clusters investigated also ate cilantro. Traceback investigations converged on three suppliers in Puebla, Mexico. Cilantro was the vehicle of infection in the four clusters investigated; the temporal association of these clusters with the large overall increase in cyclosporiasis cases in Texas suggests cilantro was the vehicle of infection for many other cases. However, the paucity of epidemiological and traceback information does not allow for a conclusive determination; moreover, molecular epidemiological tools for cyclosporiasis that could provide more definitive linkage between case clusters are needed.

Semiparametric time varying coefficient model for matched case-crossover studies.

PubMed

Ortega-Villa, Ana Maria; Kim, Inyoung; Kim, H

2017-03-15

In matched case-crossover studies, it is generally accepted that the covariates on which a case and associated controls are matched cannot exert a confounding effect on independent predictors included in the conditional logistic regression model. This is because any stratum effect is removed by the conditioning on the fixed number of sets of the case and controls in the stratum. Hence, the conditional logistic regression model is not able to detect any effects associated with the matching covariates by stratum. However, some matching covariates such as time often play an important role as an effect modification leading to incorrect statistical estimation and prediction. Therefore, we propose three approaches to evaluate effect modification by time. The first is a parametric approach, the second is a semiparametric penalized approach, and the third is a semiparametric Bayesian approach. Our parametric approach is a two-stage method, which uses conditional logistic regression in the first stage and then estimates polynomial regression in the second stage. Our semiparametric penalized and Bayesian approaches are one-stage approaches developed by using regression splines. Our semiparametric one stage approach allows us to not only detect the parametric relationship between the predictor and binary outcomes, but also evaluate nonparametric relationships between the predictor and time. We demonstrate the advantage of our semiparametric one-stage approaches using both a simulation study and an epidemiological example of a 1-4 bi-directional case-crossover study of childhood aseptic meningitis with drinking water turbidity. We also provide statistical inference for the semiparametric Bayesian approach using Bayes Factors. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Early postoperative magnet application combined with hydrocolloid dressing for the treatment of earlobe keloids.

PubMed

Park, Tae Hwan; Chang, Choong Hyun

2013-04-01

To prevent the recurrence of earlobe keloids after surgical removal, a reliable and safe postoperative treatment method is critical. To the authors' knowledge, no studies have elucidated the most effective postoperative dressing method for preventing the recurrence of earlobe keloids. This study aimed to compare keloid recurrence rates in patients whose keloids were dressed using conventional methods (plain gauze or a polyvinyl alcohol sponge) with those of a matched cohort of patients whose keloids were dressed using magnets combined with hydrocolloid materials. This observational case-control study compared a retrospective cohort of patients whose keloids were dressed using conventional methods with a matched prospective cohort of patients whose keloids were dressed using magnets combined with hydrocolloid materials. The study included patients with pathologically confirmed earlobe keloids that were surgically excised with primary closure. Patients 8 years of age or older underwent adjuvant pressure therapy with magnets at the study hospital. Patients were excluded from the study if they were unavailable for follow-up evaluation, if they had received additional adjuvant therapy during treatment, or if histologic confirmation of a keloid was not obtained. Matched-pair analysis was performed using the McNemar test. Treatment outcome was evaluated as recurrence or nonrecurrence. Overall, 9 (11.2%) of the 80 study patients experienced recurrence. The recurrence rate was significantly lower in the matched case group (2 of 40, 5%) than in the matched control group (7 of 40, 17.5%) during the follow-up period of 18 months (p=0.0253). The authors' novel dressing of magnets and hydrocolloid materials appears to be effective in reducing earlobe keloid recurrence. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Epidemiological study of the characteristics of veterinarians who pursue a research career: part I.

PubMed

Murray, J K; French, N P; Fitzpatrick, J L; Pinchbeck, G L

2005-09-24

This retrospective, matched case-control study compared the characteristics of veterinary surgeons employed in veterinary research with those who had never held a research post. The cases were randomly selected from graduates of veterinary schools in Great Britain or Ireland who were employed at universities or institutes that conduct research and who played a major role in veterinary research projects during 2001 to 2003. The controls were veterinary surgeons who had not held any post that was primarily a research post since they graduated. The cases and controls were matched by year of graduation and data were obtained for 173 matched sets. Graduates who were significantly (P<0.05) more likely to have a career involving research included male graduates, graduates who had completed a summer studentship, graduates who had completed an internship, residency or houseman's programme, graduates who held a veterinary diploma, and graduates who had intended to pursue a career in research or academia when they graduated from veterinary school. A career involving research was significantly (P<0.05) more likely to be associated with full-time employment and a lower salary than a career that did not involve research.

A matched case-control study of convenience store robbery risk factors.

PubMed

Hendricks, S A; Landsittel, D P; Amandus, H E; Malcan, J; Bell, J

1999-11-01

Convenience store clerks have been shown to be at high risk for assault and homicide, mostly owing to robbery or robbery attempts. Although the literature consistently indicates that at least some environmental designs are effective deterrents of robbery, the significance of individual interventions and policies has differed across past studies. To address these issues, a matched case-control study of 400 convenience store robberies in three metropolitan areas of Virginia was conducted. Conditional logistic regression was implemented to evaluate the significance of various environmental designs and other factors possibly related to convenience store robbery. Findings indicate that numerous characteristics of the surrounding environment and population were significantly associated with convenience store robbery. Results also showed that, on a univariate level, most crime prevention factors were significantly associated with a lower risk for robbery. Using a forward selection process, a multivariate model, which included cash handling policy, bullet-resistant shielding, and numerous characteristics of the surrounding area and population, was identified. This study addressed numerous limitations of the previous literature by prospectively collecting extensive data on a large sample of diverse convenience stores and directly addressing the current theory on the robbers' selection of a target store through a matched case-control design.

Neonatal hypoglycemia in term, nondiabetic pregnancies.

PubMed

DePuy, Amy M; Coassolo, Kara M; Som, Dara A; Smulian, John C

2009-05-01

To define the incidence of hypoglycemia and identify risk factors in neonates from term, singleton, nondiabetic pregnancies. We conducted a matched case-control study of term, singleton infants weighing more than 2500 g in nondiabetic pregnancies. Cases with hypoglycemia (glucose < 50 mg/dL) were identified by International Classification of Diseases, ninth revision, codes. Two controls per case were matched on race, maternal age, and birthweight. Conditional logistic regression analyses were performed. There were 116 cases and 232 controls studied. The incidence density of neonatal hypoglycemia was 24.7 per 1000 infant-days at risk. Hypoglycemia was less commonly associated with later gestational age (odds ratio [OR], 0.66; 95% confidence interval [CI], 0.53-0.85 per week of gestation). Maternal fever during labor was more common with hypoglycemia (OR, 4.08; 95% CI, 1.39-11.79). Public insurance was more than twice as common with hypoglycemia compared with those privately insured (OR, 2.31; 95% CI, 1.17-4.58). Neonatal hypoglycemia was associated with earlier gestational age, intrapartum fever, and public insurance.

RNA-Seq Analysis of Gene Expression, Viral Pathogen, and B-Cell/T-Cell Receptor Signatures in Complex Chronic Disease.

PubMed

Bouquet, Jerome; Gardy, Jennifer L; Brown, Scott; Pfeil, Jacob; Miller, Ruth R; Morshed, Muhammad; Avina-Zubieta, Antonio; Shojania, Kam; McCabe, Mark; Parker, Shoshana; Uyaguari, Miguel; Federman, Scot; Tang, Patrick; Steiner, Ted; Otterstater, Michael; Holt, Rob; Moore, Richard; Chiu, Charles Y; Patrick, David M

2017-02-15

Chronic fatigue syndrome (CFS) remains poorly understood. Although infections are speculated to trigger the syndrome, a specific infectious agent and underlying pathophysiological mechanism remain elusive. In a previous study, we described similar clinical phenotypes in CFS patients and alternatively diagnosed chronic Lyme syndrome (ADCLS) patients—individuals diagnosed with Lyme disease by testing from private Lyme specialty laboratories but who test negative by reference 2-tiered serologic analysis. Here, we performed blinded RNA-seq analysis of whole blood collected from 25 adults diagnosed with CFS and 13 ADCLS patients, comparing these cases to 25 matched controls and 11 patients with well-controlled systemic lupus erythematosus (SLE). Samples were collected at patient enrollment and not during acute symptom flares. RNA-seq data were used to study host gene expression, B-cell/T-cell receptor profiles (BCR/TCR), and potential viral infections. No differentially expressed genes (DEGs) were found to be significant when CFS or ADCLS cases were compared to controls. Forty-two DEGs were found when SLE cases were compared to controls, consistent with activation of interferon signaling pathways associated with SLE disease. BCR/TCR repertoire analysis did not show significant differences between CFS and controls or ADCLS and controls. Finally, viral sequences corresponding to anelloviruses, human pegivirus 1, herpesviruses, and papillomaviruses were detected in RNA-seq data, but proportions were similar (P = .73) across all genus-level taxonomic categories. Our observations do not support a theory of transcriptionally mediated immune cell dysregulation in CFS and ADCLS, at least outside of periods of acute symptom flares. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.

Biomarkers and bacterial pneumonia risk in patients with treated HIV infection: a case-control study.

PubMed

Bjerk, Sonja M; Baker, Jason V; Emery, Sean; Neuhaus, Jacqueline; Angus, Brian; Gordin, Fred M; Pett, Sarah L; Stephan, Christoph; Kunisaki, Ken M

2013-01-01

Despite advances in HIV treatment, bacterial pneumonia continues to cause considerable morbidity and mortality in patients with HIV infection. Studies of biomarker associations with bacterial pneumonia risk in treated HIV-infected patients do not currently exist. We performed a nested, matched, case-control study among participants randomized to continuous combination antiretroviral therapy (cART) in the Strategies for Management of Antiretroviral Therapy trial. Patients who developed bacterial pneumonia (cases) and patients without bacterial pneumonia (controls) were matched 1∶1 on clinical center, smoking status, age, and baseline cART use. Baseline levels of Club Cell Secretory Protein 16 (CC16), Surfactant Protein D (SP-D), C-reactive protein (hsCRP), interleukin-6 (IL-6), and d-dimer were compared between cases and controls. Cases (n = 72) and controls (n = 72) were 25.7% female, 51.4% black, 65.3% current smokers, 9.7% diabetic, 36.1% co-infected with Hepatitis B/C, and 75.0% were on cART at baseline. Median (IQR) age was 45 (41, 51) years with CD4+ count of 553 (436, 690) cells/mm(3). Baseline CC16 and SP-D were similar between cases and controls, but hsCRP was significantly higher in cases than controls (2.94 µg/mL in cases vs. 1.93 µg/mL in controls; p = 0.02). IL-6 and d-dimer levels were also higher in cases compared to controls, though differences were not statistically significant (p-value 0.06 and 0.10, respectively). In patients with cART-treated HIV infection, higher levels of systemic inflammatory markers were associated with increased bacterial pneumonia risk, while two pulmonary-specific inflammatory biomarkers, CC16 and SP-D, were not associated with bacterial pneumonia risk.

Quantifying risk factors for human brucellosis in rural northern Tanzania.

PubMed

John, Kunda; Fitzpatrick, Julie; French, Nigel; Kazwala, Rudovick; Kambarage, Dominic; Mfinanga, Godfrey S; MacMillan, Alastair; Cleaveland, Sarah

2010-04-01

Brucellosis is a zoonosis of veterinary, public health and economic significance in most developing countries. Human brucellosis is a severely debilitating disease that requires prolonged treatment with a combination of antibiotics. The disease can result in permanent and disabling sequel, and results in considerable medical expenses in addition to loss of income due to loss of working hours. A study was conducted in Northern Tanzania to determine the risk factors for transmission of brucellosis to humans in Tanzania. This was a matched case-control study. Any patient with a positive result by a competitive ELISA (c-ELISA) test for brucellosis, and presenting to selected hospitals with at least two clinical features suggestive of brucellosis such as headache, recurrent or continuous fever, sweating, joint pain, joint swelling, general body malaise or backache, was defined as a case. For every case in a district, a corresponding control was traced and matched by sex using multistage cluster sampling. Other criteria for inclusion as a control included a negative c-ELISA test result and that the matched individual would present to hospital if falls sick. Multivariable analysis showed that brucellosis was associated with assisted parturition during abortion in cattle, sheep or goat. It was shown that individuals living in close proximity to other households had a higher risk of brucellosis. People who were of Christian religion were found to have a higher risk of brucellosis compared to other religions. The study concludes that assisting an aborting animal, proximity to neighborhoods, and Christianity were associated with brucellosis infection. There was no association between human brucellosis and Human Immunodeficiency Virus (HIV) serostatus. Protecting humans against contact with fluids and tissues during assisted parturition of livestock may be an important means of reducing the risk of transferring brucellosis from livestock to humans. These can be achieved through health education to the communities where brucellosis is common.

Quantifying Risk Factors for Human Brucellosis in Rural Northern Tanzania

PubMed Central

John, Kunda; Fitzpatrick, Julie; French, Nigel; Kazwala, Rudovick; Kambarage, Dominic; Mfinanga, Godfrey S.; MacMillan, Alastair; Cleaveland, Sarah

2010-01-01

Background Brucellosis is a zoonosis of veterinary, public health and economic significance in most developing countries. Human brucellosis is a severely debilitating disease that requires prolonged treatment with a combination of antibiotics. The disease can result in permanent and disabling sequel, and results in considerable medical expenses in addition to loss of income due to loss of working hours. A study was conducted in Northern Tanzania to determine the risk factors for transmission of brucellosis to humans in Tanzania. Methods This was a matched case-control study. Any patient with a positive result by a competitive ELISA (c-ELISA) test for brucellosis, and presenting to selected hospitals with at least two clinical features suggestive of brucellosis such as headache, recurrent or continuous fever, sweating, joint pain, joint swelling, general body malaise or backache, was defined as a case. For every case in a district, a corresponding control was traced and matched by sex using multistage cluster sampling. Other criteria for inclusion as a control included a negative c-ELISA test result and that the matched individual would present to hospital if falls sick. Results Multivariable analysis showed that brucellosis was associated with assisted parturition during abortion in cattle, sheep or goat. It was shown that individuals living in close proximity to other households had a higher risk of brucellosis. People who were of Christian religion were found to have a higher risk of brucellosis compared to other religions. The study concludes that assisting an aborting animal, proximity to neighborhoods, and Christianity were associated with brucellosis infection. There was no association between human brucellosis and Human Immunodeficiency Virus (HIV) serostatus. Protecting humans against contact with fluids and tissues during assisted parturition of livestock may be an important means of reducing the risk of transferring brucellosis from livestock to humans. These can be achieved through health education to the communities where brucellosis is common. PMID:20376363

Factors associated with trace evidence analyses and DNA findings among police reported cases of rape.

PubMed

Forr, Camilla; Schei, Berit; Stene, Lise Eilin; Ormstad, Kari; Hagemann, Cecilie Therese

2018-02-01

The aim of this study was to examine the association between victim, suspect and assault characteristics and (1) forensic analysis of trace evidence, (2) detection of spermatozoa and (3) DNA match in police-reported cases of rape/attempted rape. In addition, we explored whether DNA findings were associated with legal outcome. We conducted a retrospective, descriptive study based on police-reported rapes and attempted rapes of women  ≥16 years of age in Sør-Trøndelag Police District throughout 1997-2010. Police data were merged with information from the Sexual Assault Centre (SAC) at St. Olavs University Hospital, Trondheim, Norway. We used binary and multivariable logistic regression for the comparisons. We identified 324 victims (mean age 24 years). The police requested analysis in 135 (45%) of the 299 collected victim samples. The police decision to analyze was after adjustment associated with the victim being employed or under education, and a public venue, but not with interval from assault to sampling. Spermatozoa were detected in 79 (61%) of the analyzed cases, of which 71 were collected from victims within 24h. Interval from assault being <24h and reporting a penetrative assault remained associated with the findings of spermatozoa after adjustments. Forensic analyses of trace evidence collected from victim, suspect and/or venue disclosed matching DNA profiles in 57 (40%) of a total of 143 analyzed cases. Matching DNA profiles were associated with suspect being known to the victim and with the venue being private. A higher proportion of cases with a DNA match were prosecuted in court: 20 of the 29 cases prosecuted. However, despite a DNA match 35 cases were anyway dismissed because of insufficient evidence. Although many of the associations in our study were expected, it is still important to report the actual numbers to gain insight into the importance of a DNA match in legal proceedings. A substantial proportion of cases with DNA match was dismissed because of insufficient evidence. To strengthen the justice response to sexual assault, it is essential to generate knowledge about the role of medico-legal evidence in such cases, and there are obviously other non-medical factors influencing the legal decisions. Copyright © 2017 Elsevier B.V. All rights reserved.

Using Clustering Strategies for Creating Authority Files.

ERIC Educational Resources Information Center

French, James C.; Powell, Allison L.; Schulman, Eric

2000-01-01

Discussion of quality control of data in online bibliographic databases focuses on authority files. Describes approximate string matching, introduces the concept of approximate word matching and clustering, and presents a case study using the Astrophysics Data System (ADS) that shows how to reduce human effort involved in authority work. (LRW)

Mix and match: how to regain your balance.

PubMed

Jupiter, Daniel C

2013-01-01

In retrospective studies, a demographic imbalance often exists between cases and controls. This imbalance may affect outcome, independent of experimental group. We discuss matching methods that allow us to overcome these imbalances. Copyright © 2013 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

Fried food and prostate cancer risk: systematic review and meta-analysis.

PubMed

Lippi, Giuseppe; Mattiuzzi, Camilla

2015-01-01

We performed systematic review and meta-analysis of published studies that investigated the potential association between fried food consumption and prostate cancer risk. Four case-control studies were finally selected for this systematic literature review, totaling 2579 cancer patients and 2277 matched controls. In two of these studies, the larger intake of fried food was associated with a 1.3- to 2.3-fold increased risk of prostate cancer, no significant association was found in another, whereas an inverse relationship was observed in the remaining. The meta-analysis of published data showed that larger intake of fried food was associated with a 35% (95% CI 17-57%) increased risk of prostate cancer. The results of this systematic literature review support the notion that larger intake of fried foods may have a role in increasing the risk of prostate cancer.

[Risk factors for the kidney stones: a hospital-based case-control study in a distric hospital in Beijing].

PubMed

Wang, Jiao; Luo, Gong-tang; Niu, Wei-jing; Gong, Man-man; Liu, Lu; Zhou, Jie; Zhou, Xue-wei; He, Li-hua

2013-12-18

To explore the risk and protective factors of kidney calculi in order to put forward theoretical basis for preventive and control measures. A 1:1 matched case-control study was performed using data from a hospital in Beijing. The case group included 100 inpatients who were diagnosed kidney calculi using B ultrasonic, X-ray and intravenous pyelography during the survey while other 100 urolithiasis and endocrine disease excluded inpatients who shared the same sex, within five years gap to the case group inpatients were for the control group. A face-to-face survey was conducted with self-made questionnaires which covered demographic characteristics, water issues, dietary habits, genetic and medical history. Epidata 3.0 was used to build the database and SPSS 19.0 for the statistical analysis. In the univariate Logistic regression analysis, ten variables were found showing statistical significance. For the multivariate Logistic regression analysis, variables left in the model were labor intensity (OR=0.622, 95%CI: 0.435-0.889), preferring to drink after dinner (OR=0.316, 95%CI: 0.122-0.815), loving drinking (OR=0.232, 95%CI: 0.084-0.642), drinking tea regularly (OR=1.463, 95%CI: 1.033-2.071), eating more vegetables (OR=0.571, 95%CI: 0.328-0.993), the history of the urolithiasis (OR=2.127, 95%CI: 1.065-90.145). Drinking tea regularly, urolithiasis history and brain work are the risk factors of kidney calculi while loving drinking and eating more vegetables for the protection.

Dermal Structure in Lymphedema Patients with History of Acute Dermatolymphangioadenitis Evaluated by Histogram Analysis of Ultrasonography Findings: A Case-Control Study.

PubMed

Dai, Misako; Sato, Aya; Maeba, Hiroko; Iuchi, Terumi; Matsumoto, Masaru; Okuwa, Mayumi; Nakatani, Toshio; Sanada, Hiromi; Sugama, Junko

2016-03-01

Acute dermatolymphangioadenitis (ADLA) is a risk factor for increasing of edema and worsening severity. Reducing ADLA frequency is an important objective of lymphedema management because ADLA episodes are strongly associated with poor quality of life. Lymphedema changes dermal and subcutaneous structure, favoring ADLA; ADLA recurrence may be caused by structural change of the dermis. However, the structure of the skin following ADLA episodes has not been studied in depth. The aim of this study was to examine changes in the skin after episodes of ADLA in breast cancer-related lymphedema (BCRL) using histogram analysis of ultrasonography findings. This was a case-control study with matching for the duration of lymphedema. We compared 10 limbs (5 BCRL patients, Cases) with a history of ADLA and 14 limbs (7 BCRL patients, Controls) without. Ultrasonography was performed using a 20-MHz probe, and measurements were made at a site 10 cm proximal to the ulnar styloid process. We compared "skewness" of the images in the dermis from the histogram analysis. This study was approved by the Ethics Committee of Kanazawa University. Skewness was significantly different between the affected and unaffected limbs (p = 0.02). Cases showed a positive value (median 0.74, range -0.18 to 1.26), whereas Controls showed a negative value (median -0.21, range -0.45 to 0.31). Episodes of ADLA changed the distribution of echogenicity on imaging, which indicates a change in the collagen fibers in the dermis. These findings might contribute to improving the management of lymphedema and prevention of recurrent ADLA.

[Risk factors for surgical site infections in patients undergoing craniotomy].

PubMed

Cha, Kyeong-Sook; Cho, Ok-Hee; Yoo, So-Yeon

2010-04-01

The objectives of this study were to determine the prevalence, incidence, and risk factors for postoperative surgical site infections (SSIs) after craniotomy. This study was a retrospective case-control study of 103 patients who had craniotomies between March 2007 and December 2008. A retrospective review of prospectively collected databases of consecutive patients who underwent craniotomy was done. SSIs were defined by using the Centers for Disease Control criteria. Twenty-six cases (infection) and 77 controls (no infection) were matched for age, gender and time of surgery. Descriptive analysis, t-test, X(2)-test and logistic regression analyses were used for data analysis. The statistical difference between cases and controls was significant for hospital length of stay (>14 days), intensive care unit stay more than 15 days, Glasgrow Coma Scale (GCS) score (< or = 7 days), extra-ventricular drainage and coexistent infection. Risk factors were identified by logistic regression and included hospital length of stay of more than 14 days (odds ratio [OR]=23.39, 95% confidence interval [CI]=2.53-216.11) and GCS score (< or = 7 scores) (OR=4.71, 95% CI=1.64-13.50). The results of this study show that patients are at high risk for infection when they have a low level of consciousness or their length hospital stay is long term. Nurses have to take an active and continuous approach to infection control to help with patients having these risk factors.

Plasma fatty acids, oxylipins, and risk of myocardial infarction: the Singapore Chinese health study

USDA-ARS?s Scientific Manuscript database

Objective: We aimed to examine the prospective association between plasma fatty acids (FAs), oxylipins and risk of acute myocardial infarction (AMI) in a Singapore Chinese population. Methods: A nested case-control study with 744 incident AMI cases and 744 matched controls aged 47-83 years was condu...

Prenatal and Perinatal Risk Factors for Autism in China

ERIC Educational Resources Information Center

Zhang, Xin; Lv, Cong-Chao; Tian, Jiang; Miao, Ru-Juan; Xi, Wei; Hertz-Picciotto, Irva; Qi, Lihong

2010-01-01

We conducted a case-control study using 190 Han children with and without autism to investigate prenatal and perinatal risk factors for autism in China. Cases were recruited through public special education schools and controls from regular public schools in the same region (Tianjin), with frequency matching on sex and birth year. Unadjusted…