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Sample records for multicenter case-control samples

  1. Occupational risk factors for mycosis fungoides: a European multicenter case-control study.

    PubMed

    Morales-Suárez-Varela, Maria M; Olsen, Jorn; Johansen, Preben; Kaerlev, Linda; Guénel, Pascal; Arveux, Patrick; Wingren, Gun; Hardell, Lennart; Ahrens, Wolfgang; Stang, Andreas; Llopis, Agustin; Merletti, Franco; Aurrekoetxea, Juan Jose; Masala, Giovanna

    2004-03-01

    Mycosis fungoides (MF) is a rare disease with an unknown etiology. Its distribution suggests that occupational exposures may play a role. In the present study, we searched for occupational factors associated with MF. A European multicenter case-control study on seven rare cancers, including MF, was conducted from 1995 to 1997. Patients between 35 and 69 years of age diagnosed with MF (n = 134) were identified and their diagnoses were checked by a reference pathologist who classified 83 cases as definitive, 35 cases as possible, and 16 cases as not histologically verified. Of the 118 histologically verified cases, 104 were interviewed, of which 76 were definitive cases. As controls, we selected population controls and colon cancer controls to serve all seven case groups. Altogether, 833 colon cancer controls and 2071 population controls were interviewed. The response rate was 91.5% for cases (76 of the 83 definitive cases), and 66.6% for controls. A high risk of MF for men was observed in the industries of other non-metallic mineral products (Odds Ratio [OR] 5.3, 95% confidence interval [CI] = 1.7-16.2) and of wholesale trade (OR 3.6, 95% CI = 1.3-10.5). A high risk was found for female employees in the sector of pulp paper manufacture (OR 14.4, 95% CI = 2.2-95.1). The male occupations with the highest risks were glass formers, potters, and ceramics workers (OR 17.9, 95% CI = 5.4-59.4) and technical salesmen (OR 8.6, 95% CI = 2.4-30.8). For women, the occupations associated with the highest risks were government executives (OR 4.8, 95% CI = 1.0-22.6) and railway and road vehicles loaders (OR 3.9, 95% CI = 1.0-14.0). The results suggest that some occupational factors are associated with MF. Working as glass formers, pottery, and ceramics workers carried the highest risk, and these findings deserve further attention and replication. Females working in the paper and pulp industries may also be exposed to carcinogens of relevance to MF.

  2. Risk factors for operated carpal tunnel syndrome: a multicenter population-based case-control study

    PubMed Central

    Mattioli, Stefano; Baldasseroni, Alberto; Bovenzi, Massimo; Curti, Stefania; Cooke, Robin MT; Campo, Giuseppe; Barbieri, Pietro G; Ghersi, Rinaldo; Broccoli, Marco; Cancellieri, Maria Pia; Colao, Anna Maria; dell'Omo, Marco; Fateh-Moghadam, Pirous; Franceschini, Flavia; Fucksia, Serenella; Galli, Paolo; Gobba, Fabriziomaria; Lucchini, Roberto; Mandes, Anna; Marras, Teresa; Sgarrella, Carla; Borghesi, Stefano; Fierro, Mauro; Zanardi, Francesca; Mancini, Gianpiero; Violante, Francesco S

    2009-01-01

    Background Carpal tunnel syndrome (CTS) is a socially and economically relevant disease caused by compression or entrapment of the median nerve within the carpal tunnel. This population-based case-control study aims to investigate occupational/non-occupational risk factors for surgically treated CTS. Methods Cases (n = 220) aged 18-65 years were randomly drawn from 13 administrative databases of citizens who were surgically treated with carpal tunnel release during 2001. Controls (n = 356) were randomly sampled from National Health Service registry records and were frequency matched by age-gender-specific CTS hospitalization rates. Results At multivariate analysis, risk factors were blue-collar/housewife status, BMI ≥ 30 kg/m2, sibling history of CTS and coexistence of trigger finger. Being relatively tall (cut-offs based on tertiles: women ≥165 cm; men ≥175 cm) was associated with lower risk. Blue-collar work was a moderate/strong risk factor in both sexes. Raised risks were apparent for combinations of biomechanical risk factors that included frequent repetitivity and sustained force. Conclusion This study strongly underlines the relevance of biomechanical exposures in both non-industrial and industrial work as risk factors for surgically treated CTS. PMID:19758429

  3. Lifestyle factors and lumbar disc disease: results of a German multi-center case-control study (EPILIFT)

    PubMed Central

    2010-01-01

    Introduction In the large-scale case-control study EPILIFT, we investigated the dose-response relationship between lifestyle factors (weight, smoking amount, cumulative duration of different sports activities) and lumbar disc disease. Methods In four German study regions (Frankfurt am Main, Freiburg, Halle/Saale, Regensburg), 564 male and female patients with lumbar disc herniation and 351 patients with lumbar disc narrowing (chondrosis) aged 25 to 70 years were prospectively recruited. From the regional population registers, 901 population control subjects were randomly selected. In a structured personal interview, we enquired as to body weight at different ages, body height, cumulative smoking amount and cumulative duration of different sports activities. Confounders were selected according to biological plausibility and to the change-in-estimate criterion. Adjusted, gender-stratified odds ratios with 95% confidence intervals were calculated using unconditional logistic regression analysis. Results The results of this case-control study reveal a positive association between weight and lumbar disc herniation as well as lumbar disc narrowing among men and women. A medium amount of pack-years was associated with lumbar disc herniation and narrowing in men and women. A non-significantly lowered risk of lumbar disc disease was found in men with high levels of cumulative body building and strength training. Conclusions According to our multi-center case-control study, body weight might be related to lumbar disc herniation as well as to lumbar disc narrowing. Further research should clarify the potential protective role of body building or strength training on lumbar disc disease. PMID:20955546

  4. Occupation and skin cancer: the results of the HELIOS-I multicenter case-control study

    PubMed Central

    Suárez, Berta; López-Abente, Gonzalo; Martínez, Carmen; Navarro, Carmen; Tormo, Maria José; Rosso, Stefano; Schraub, Simon; Gafà, Lorenzo; Sancho-Garnier, Hélène; Wechsler, Janine; Zanetti, Roberto

    2007-01-01

    Background Non-melanoma skin cancer (NMSC) is the most frequent tumour among Caucasian populations worldwide. Among the risk factors associated with this tumour, there are host-related factors and several environmental agents. A greater likelihood of high exposure to physical agents (with the exception of solar radiation) and chemical agents depends on the work setting. Our objective is to evaluate the role of occupational exposures in NMSC, with special emphasis on risk factors other than solar radiation and skin type. Methods We analysed 1585 cases (1333 basal cell carcinoma (BCC) and 183 squamous cell carcinoma (SCC)) and 1507 controls drawn from the Helios-I multicenter study. Odds ratios (OR) and 95% confidence intervals (CI) were estimated using logistic regression mixed models. Results For NMSC as a whole (both histological types), miners and quarrymen, secondary education teachers, and masons registered excess risk, regardless of exposure to solar radiation and skin type (OR 7.04, 95% CI 2.44–20.31; OR 1.75, 95% CI 1.05–2.89 and OR 1.54, 95% CI 1.04–2.27, respectively). Frequency of BCC proved higher among railway engine drivers and firemen (OR 4.55; 95% CI 0.96–21.57), specialised farmers (OR 1.65; 95% CI 1.05–2.59) and salesmen (OR 3.02; 95% CI 1.05–2.86), in addition to miners and quarrymen and secondary education teachers (OR 7.96; 95% CI 2.72–23.23 and OR 1.76; 95% CI 1.05–2.94 respectively). The occupations that registered a higher risk of SCC (though not of BCC) were those involving direct contact with livestock, construction workers not elsewhere classified (OR 2.95, 95% CI 1.12–7.74), stationary engine and related equipment operators not elsewhere classified (OR 5.31, 95% CI 1.13–21.04) and masons (OR 2.55, 95% CI 1.36–4.78). Conclusion Exposure to hazardous air pollutants, arsenic, ionizing radiations and burns may explain a good part of the associations observed in this study. The Helios study affords an excellent

  5. Risk Factors for Pancreatic Cancer in China: A Multicenter Case-Control Study

    PubMed Central

    Zheng, Zhaoxu; Zheng, Rongshou; He, Yutong; Sun, Xibin; Wang, Ning; Chen, Tianhui; Chen, Wanqing

    2016-01-01

    Background Despite having one of the highest mortality rates of all cancers, the risk factors of pancreatic cancer remain unclear. We assessed risk factors of pancreatic cancer in China. Methods A case-control study design was conducted using data from four hospital-based cancer registries (Henan Provincial Cancer Hospital, Beijing Cancer Hospital, Hebei Provincial Cancer Hospital, and Cancer Hospital of Chinese Academy of Medical Sciences). Controls were equally matched and selected from family members of non-pancreatic cancer patients in the same hospitals. Face-to-face interviews were conducted by trained staff using questionnaires. Conditional logistic regression models were used to assess odd ratios (ORs) and 95% confident intervals (CIs). Results Among 646 recruited participants, 323 were pancreatic cancer patients and 323 were controls. Multivariate logistic analysis suggested that pancreatic cancer family history (adjusted OR 1.23; 95% CI, 1.11–3.70), obesity (adjusted OR 1.77; 95% CI, 1.22–2.57), diabetes (adjusted OR 2.96; 95% CI, 1.48–5.92) and smoking (adjusted OR 1.78; 95% CI, 1.02–3.10) were risk factors for pancreatic cancer, but that drinking tea (adjusted OR 0.49; 95% CI, 0.25–0.84) was associated with reduced risk of pancreatic cancer. Conclusions Cigarette smoking, family history, obesity, and diabetes are risk factors of pancreatic cancer, which is important information for designing early intervention and preventive strategies for pancreatic cancer and may be beneficial to pancreatic cancer control in China. PMID:26441209

  6. Bile acids in a multicenter, population-based case-control study of stillbirth

    PubMed Central

    Silver, Robert M.; Parker, Corette B.; Goldenberg, Robert; Reddy, Uma M.; Dudley, Donald J.; Saade, George R.; Hogue, Carol J. Rowland; Coustan, Donald; Varner, Michael W.; Koch, Matthew A.; Conway, Deborah; Bukowski, Radek; Pinar, Halit; Stoll, Barbara; Moore, Janet; Willinger, Marian

    2015-01-01

    OBJECTIVE We sought to compare bile acids in women with and without stillbirth in a population-based study. STUDY DESIGN The Stillbirth Collaborative Research Network conducted a multisite, population-based case-control study of stillbirth (fetal deaths ≥20 weeks). Maternal sera were obtained at the time of enrollment and frozen at −80° until assay for bile acids. RESULTS Assays were performed in 581 women with stillbirth and 1546 women with live births. Bile acid levels were slightly higher in women with stillbirth (geometric mean [95% confidence interval {CI}] = 3.2 [3.0–3.5]) compared to live births (2.9 [2.7–3.1], P = .0327). However, the difference was not significant after adjustment for baseline risk factors for stillbirth. The proportion of women with elevated levels (≥10 or ≥40 μmol/L) was similar in stillbirths and live births. Results were similar when the analysis was limited to subsets of stillbirths and live births. In women with stillbirths not associated with fetal anomalies or obstetric complications bile acid levels were higher than in women with term live births (geometric mean [95% CI] = 3.4 [3.0–3.8] vs 2.9 [2.7–3.0], P = .0152, unadjusted; P = .06, adjusted). However, a similar proportion of women in both groups had levels ≥10 mmol/L (10.7 vs 7.2%; odds ratio [OR], 1.54; 95% CI, 0.97–2.44; adjusted OR, 1.29; 95% CI, 0.78–2.15) and ≥40 μmol/L (1.7 vs 0.7%; OR, 2.58; 95% CI, 0.85–7.84; adjusted OR, 2.28; 95% CI, 0.79–6.56). CONCLUSION Our data do not support testing for bile acids in cases of stillbirth in the absence of clinical evidence of intrahepatic cholestasis of pregnancy. PMID:24215860

  7. Acute Middle Gastrointestinal Bleeding Risk Associated with NSAIDs, Antithrombotic Drugs, and PPIs: A Multicenter Case-Control Study

    PubMed Central

    Nagata, Naoyoshi; Niikura, Ryota; Yamada, Atsuo; Sakurai, Toshiyuki; Shimbo, Takuro; Kobayashi, Yuka; Okamoto, Makoto; Mitsuno, Yuzo; Ogura, Keiji; Hirata, Yoshihiro; Fujimoto, Kazuma; Akiyama, Junichi; Uemura, Naomi; Koike, Kazuhiko

    2016-01-01

    Background Middle gastrointestinal bleeding (MGIB) risk has not been fully investigated due to its extremely rare occurrence and the need for multiple endoscopies to exclude upper and lower gastrointestinal bleeding. This study investigated whether MGIB is associated with the use of non-steroidal anti-inflammatory drugs (NSAIDs), low-dose aspirin (LDA), thienopyridines, anticoagulants, and proton-pump inhibitors (PPIs), and whether PPI use affects the interactions between MGIB and antithrombotic drugs. Methods In this multicenter, hospital-based, case-control study, 400 patients underwent upper and lower endoscopy, 80 had acute overt MGIB and 320 had no bleeding and were matched for age and sex as controls (1:4). MGIB was additionally evaluated by capsule and/or double-balloon endoscopy, after excluding upper and lower GI bleeding. Adjusted odds ratios (AOR) for MGIB risk were calculated using conditional logistic regression. To estimate the propensity score, we employed a logistic regression model for PPI use. Results In patients with MGIB, mean hemoglobin level was 9.4 g/dL, and 28 patients (35%) received blood transfusions. Factors significantly associated with MGIB were chronic kidney disease (p<0.001), liver cirrhosis (p = 0.034), NSAIDs (p<0.001), thienopyridines (p<0.001), anticoagulants (p = 0.002), and PPIs (p<0.001). After adjusting for these factors, NSAIDs (AOR, 2.5; p = 0.018), thienopyridines (AOR, 3.2; p = 0.015), anticoagulants (AOR, 4.3; p = 0.028), and PPIs (AOR; 2.0; p = 0.021) were independently associated with MGIB. After adjusting for propensity score, the use of PPIs remained an independent risk factors for MGIB (AOR, 1.94; p = 0.034). No significant interactions were observed between PPIs and NSAIDs (AOR, 0.7; p = 0.637), LDA (AOR, 0.3; p = 0.112), thienopyridine (AOR, 0.7, p = 0.671), or anticoagulants (AOR, 0.5; p = 0.545). Conclusions One-third of patients with acute small intestinal bleeding required blood transfusion. NSAIDs

  8. LOCAL CASE-CONTROL SAMPLING: EFFICIENT SUBSAMPLING IN IMBALANCED DATA SETS

    PubMed Central

    Fithian, William; Hastie, Trevor

    2014-01-01

    For classification problems with significant class imbalance, subsampling can reduce computational costs at the price of inflated variance in estimating model parameters. We propose a method for subsampling efficiently for logistic regression by adjusting the class balance locally in feature space via an accept–reject scheme. Our method generalizes standard case-control sampling, using a pilot estimate to preferentially select examples whose responses are conditionally rare given their features. The biased subsampling is corrected by a post-hoc analytic adjustment to the parameters. The method is simple and requires one parallelizable scan over the full data set. Standard case-control sampling is inconsistent under model misspecification for the population risk-minimizing coefficients θ*. By contrast, our estimator is consistent for θ* provided that the pilot estimate is. Moreover, under correct specification and with a consistent, independent pilot estimate, our estimator has exactly twice the asymptotic variance of the full-sample MLE—even if the selected subsample comprises a miniscule fraction of the full data set, as happens when the original data are severely imbalanced. The factor of two improves to 1+1c if we multiply the baseline acceptance probabilities by c > 1 (and weight points with acceptance probability greater than 1), taking roughly 1+c2 times as many data points into the subsample. Experiments on simulated and real data show that our method can substantially outperform standard case-control subsampling. PMID:25492979

  9. Mendelian randomization studies for a continuous exposure under case-control sampling.

    PubMed

    Dai, James Y; Zhang, Xinyi Cindy

    2015-03-15

    In this article, we assess the impact of case-control sampling on mendelian randomization analyses with a dichotomous disease outcome and a continuous exposure. The 2-stage instrumental variables (2SIV) method uses the prediction of the exposure given genotypes in the logistic regression for the outcome and provides a valid test and an approximation of the causal effect. Under case-control sampling, however, the first stage of the 2SIV procedure becomes a secondary trait association, which requires proper adjustment for the biased sampling. Through theoretical development and simulations, we compare the naïve estimator, the inverse probability weighted estimator, and the maximum likelihood estimator for the first-stage association and, more importantly, the resulting 2SIV estimates of the causal effect. We also include in our comparison the causal odds ratio estimate derived from structural mean models by double-logistic regression. Our results suggest that the naïve estimator is substantially biased under the alternative, yet it remains unbiased under the null hypothesis of no causal effect; the maximum likelihood estimator yields smaller variance and mean squared error than other estimators; and the structural mean models estimator delivers the smallest bias, though generally incurring a larger variance and sometimes having issues in algorithm stability and convergence.

  10. The Global Enteric Multicenter Study (GEMS) of Diarrheal Disease in Infants and Young Children in Developing Countries: Epidemiologic and Clinical Methods of the Case/Control Study

    PubMed Central

    Kotloff, Karen L.; Blackwelder, William C.; Nasrin, Dilruba; Nataro, James P.; Farag, Tamer H.; van Eijk, Annemieke; Adegbola, Richard A.; Alonso, Pedro L.; Breiman, Robert F.; Golam Faruque, Abu Syed; Saha, Debasish; Sow, Samba O.; Sur, Dipika; Zaidi, Anita K. M.; Biswas, Kousick; Panchalingam, Sandra; Clemens, John D.; Cohen, Dani; Glass, Roger I.; Mintz, Eric D.; Sommerfelt, Halvor; Levine, Myron M.

    2012-01-01

    Background. Diarrhea is a leading cause of illness and death among children aged <5 years in developing countries. This paper describes the clinical and epidemiological methods used to conduct the Global Enteric Multicenter Study (GEMS), a 3-year, prospective, age-stratified, case/control study to estimate the population-based burden, microbiologic etiology, and adverse clinical consequences of acute moderate-to-severe diarrhea (MSD) among a censused population of children aged 0–59 months seeking care at health centers in sub-Saharan Africa and South Asia. Methods. GEMS was conducted at 7 field sites, each serving a population whose demography and healthcare utilization practices for childhood diarrhea were documented. We aimed to enroll 220 MSD cases per year from selected health centers serving each site in each of 3 age strata (0–11, 12–23, and 24–59 months), along with 1–3 matched community controls. Cases and controls supplied clinical, epidemiologic, and anthropometric data at enrollment and again approximately 60 days later, and provided enrollment stool specimens for identification and characterization of potential diarrheal pathogens. Verbal autopsy was performed if a child died. Analytic strategies will calculate the fraction of MSD attributable to each pathogen and the incidence, financial costs, nutritional consequences, and case fatality overall and by pathogen. Conclusions. When completed, GEMS will provide estimates of the incidence, etiology, and outcomes of MSD among infants and young children in sub-Saharan Africa and South Asia. This information can guide development and implementation of public health interventions to diminish morbidity and mortality from diarrheal diseases. PMID:23169936

  11. Effective sample size: Quick estimation of the effect of related samples in genetic case-control association analyses.

    PubMed

    Yang, Yaning; Remmers, Elaine F; Ogunwole, Chukwuma B; Kastner, Daniel L; Gregersen, Peter K; Li, Wentian

    2011-02-01

    Affected relatives are essential for pedigree linkage analysis, however, they cause a violation of the independent sample assumption in case-control association studies. To avoid the correlation between samples, a common practice is to take only one affected sample per pedigree in association analysis. Although several methods exist in handling correlated samples, they are still not widely used in part because these are not easily implemented, or because they are not widely known. We advocate the effective sample size method as a simple and accessible approach for case-control association analysis with correlated samples. This method modifies the chi-square test statistic, p-value, and 95% confidence interval of the odds-ratio by replacing the apparent number of allele or genotype counts with the effective ones in the standard formula, without the need for specialized computer programs. We present a simple formula for calculating effective sample size for many types of relative pairs and relative sets. For allele frequency estimation, the effective sample size method captures the variance inflation exactly. For genotype frequency, simulations showed that effective sample size provides a satisfactory approximation. A gene which is previously identified as a type 1 diabetes susceptibility locus, the interferon-induced helicase gene (IFIH1), is shown to be significantly associated with rheumatoid arthritis when the effective sample size method is applied. This significant association is not established if only one affected sib per pedigree were used in the association analysis. Relationship between the effective sample size method and other methods - the generalized estimation equation, variance of eigenvalues for correlation matrices, and genomic controls - are discussed.

  12. Effective Sample Size: Quick Estimation of the Effect of Related Samples in Genetic Case-Control Association Analyses

    PubMed Central

    Yang, Yaning; Remmers, Elaine F.; Ogunwole, Chukwuma B.; Kastner, Daniel L.; Gregersen, Peter K.; Li, Wentian

    2011-01-01

    Summary Affected relatives are essential for pedigree linkage analysis, however, they cause a violation of the independent sample assumption in case-control association studies. To avoid the correlation between samples, a common practice is to take only one affected sample per pedigree in association analysis. Although several methods exist in handling correlated samples, they are still not widely used in part because these are not easily implemented, or because they are not widely known. We advocate the effective sample size method as a simple and accessible approach for case-control association analysis with correlated samples. This method modifies the chi-square test statistic, p-value, and 95% confidence interval of the odds-ratio by replacing the apparent number of allele or genotype counts with the effective ones in the standard formula, without the need for specialized computer programs. We present a simple formula for calculating effective sample size for many types of relative pairs and relative sets. For allele frequency estimation, the effective sample size method captures the variance inflation exactly. For genotype frequency, simulations showed that effective sample size provides a satisfactory approximation. A gene which is previously identified as a type 1 diabetes susceptibility locus, the interferon-induced helicase gene (IFIH1), is shown to be significantly associated with rheumatoid arthritis when the effective sample size method is applied. This significant association is not established if only one affected sib per pedigree were used in the association analysis. Relationship between the effective sample size method and other methods – the generalized estimation equation, variance of eigenvalues for correlation matrices, and genomic controls – are discussed. PMID:21333602

  13. Effective sample size: Quick estimation of the effect of related samples in genetic case-control association analyses.

    PubMed

    Yang, Yaning; Remmers, Elaine F; Ogunwole, Chukwuma B; Kastner, Daniel L; Gregersen, Peter K; Li, Wentian

    2011-02-01

    Affected relatives are essential for pedigree linkage analysis, however, they cause a violation of the independent sample assumption in case-control association studies. To avoid the correlation between samples, a common practice is to take only one affected sample per pedigree in association analysis. Although several methods exist in handling correlated samples, they are still not widely used in part because these are not easily implemented, or because they are not widely known. We advocate the effective sample size method as a simple and accessible approach for case-control association analysis with correlated samples. This method modifies the chi-square test statistic, p-value, and 95% confidence interval of the odds-ratio by replacing the apparent number of allele or genotype counts with the effective ones in the standard formula, without the need for specialized computer programs. We present a simple formula for calculating effective sample size for many types of relative pairs and relative sets. For allele frequency estimation, the effective sample size method captures the variance inflation exactly. For genotype frequency, simulations showed that effective sample size provides a satisfactory approximation. A gene which is previously identified as a type 1 diabetes susceptibility locus, the interferon-induced helicase gene (IFIH1), is shown to be significantly associated with rheumatoid arthritis when the effective sample size method is applied. This significant association is not established if only one affected sib per pedigree were used in the association analysis. Relationship between the effective sample size method and other methods - the generalized estimation equation, variance of eigenvalues for correlation matrices, and genomic controls - are discussed. PMID:21333602

  14. Cumulative occupational lumbar load and lumbar disc disease – results of a German multi-center case-control study (EPILIFT)

    PubMed Central

    Seidler, Andreas; Bergmann, Annekatrin; Jäger, Matthias; Ellegast, Rolf; Ditchen, Dirk; Elsner, Gine; Grifka, Joachim; Haerting, Johannes; Hofmann, Friedrich; Linhardt, Oliver; Luttmann, Alwin; Michaelis, Martina; Petereit-Haack, Gabriela; Schumann, Barbara; Bolm-Audorff, Ulrich

    2009-01-01

    Background The to date evidence for a dose-response relationship between physical workload and the development of lumbar disc diseases is limited. We therefore investigated the possible etiologic relevance of cumulative occupational lumbar load to lumbar disc diseases in a multi-center case-control study. Methods In four study regions in Germany (Frankfurt/Main, Freiburg, Halle/Saale, Regensburg), patients seeking medical care for pain associated with clinically and radiologically verified lumbar disc herniation (286 males, 278 females) or symptomatic lumbar disc narrowing (145 males, 206 females) were prospectively recruited. Population control subjects (453 males and 448 females) were drawn from the regional population registers. Cases and control subjects were between 25 and 70 years of age. In a structured personal interview, a complete occupational history was elicited to identify subjects with certain minimum workloads. On the basis of job task-specific supplementary surveys performed by technical experts, the situational lumbar load represented by the compressive force at the lumbosacral disc was determined via biomechanical model calculations for any working situation with object handling and load-intensive postures during the total working life. For this analysis, all manual handling of objects of about 5 kilograms or more and postures with trunk inclination of 20 degrees or more are included in the calculation of cumulative lumbar load. Confounder selection was based on biologic plausibility and on the change-in-estimate criterion. Odds ratios (OR) and 95% confidence intervals (CI) were calculated separately for men and women using unconditional logistic regression analysis, adjusted for age, region, and unemployment as major life event (in males) or psychosocial strain at work (in females), respectively. To further elucidate the contribution of past physical workload to the development of lumbar disc diseases, we performed lag-time analyses. Results We

  15. Spanish Multicenter Normative Studies (NEURONORMA Project): methods and sample characteristics.

    PubMed

    Peña-Casanova, Jordi; Blesa, Rafael; Aguilar, Miquel; Gramunt-Fombuena, Nina; Gómez-Ansón, Beatriz; Oliva, Rafael; Molinuevo, José Luis; Robles, Alfredo; Barquero, María Sagrario; Antúnez, Carmen; Martínez-Parra, Carlos; Frank-García, Anna; Fernández, Manuel; Alfonso, Verónica; Sol, Josep M

    2009-06-01

    This paper describes the methods and sample characteristics of a series of Spanish normative studies (The NEURONORMA project). The primary objective of our research was to collect normative and psychometric information on a sample of people aged over 49 years. The normative information was based on a series of selected, but commonly used, neuropsychological tests covering attention, language, visuo-perceptual abilities, constructional tasks, memory, and executive functions. A sample of 356 community dwelling individuals was studied. Demographics, socio-cultural, and medical data were collected. Cognitive normality was validated via informants and a cognitive screening test. Norms were calculated for midpoint age groups. Effects of age, education, and sex were determined. The use of these norms should improve neuropsychological diagnostic accuracy in older Spanish subjects. These data may also be of considerable use for comparisons with other normative studies. Limitations of these normative data are also commented on.

  16. Maté drinking and esophageal squamous cell carcinoma in South America: pooled results from two large multi-center case-control studies

    PubMed Central

    Lubin, Jay H.; De Stefani, Eduardo; Abnet, Christian C.; Acosta, Gisele; Boffetta, Paolo; Victora, Cesar; Graubard, Barry I.; Muñoz, Nubia; Deneo-Pellegrini, Hugo; Franceschi, Silvia; Castellsagué, Xavier; Ronco, Alvaro L; Dawsey, Sanford M.

    2013-01-01

    Background Maté tea is non-alcoholic infusion widely consumed in southern South America, and may increase risk of esophageal squamous cell carcinoma (ESCC) and other cancers due to polycyclic aromatic hydrocarbons and/or thermal injury. Methods We pooled two case-control studies: a 1988–2005 Uruguay study and a 1986–1992 multinational study in Argentina, Brazil, Paraguay and Uruguay, including 1,400 cases and 3,229 controls. We computed odds ratios (OR) and fitted a linear excess odds ratio (EOR) model for cumulative maté consumption in liters/day-year (LPDY). Results The adjusted OR for ESCC with 95% confidence interval (CI) by ever compared with never use of maté was 1.60 (1.2,2.2). ORs increased linearly with LPDY (test of non-linearity, P=0.69). The estimate of slope (EOR/LPDY) was 0.009 (0.005,0.014) and did not vary with daily intake, indicating maté intensity did not influence the strength of association. EOR/LPDY estimates for consumption at warm, hot and very hot beverage temperatures were 0.004 (−0.002,0.013), 0.007 (0.003,0.013) and 0.016 (0.009,0.027), respectively, and differed significantly (P<0.01). EOR/LPDY estimates were increased in younger (<65) individuals and never alcohol drinkers, but these evaluations were post hoc, and were homogeneous by sex. Conclusions ORs for ESCC increased linearly with cumulative maté consumption and were unrelated to intensity, so greater daily consumption for shorter duration or lesser daily consumption for longer duration resulted in comparable ORs. The strength of association increased with higher mate temperatures. Impact Increased understanding of cancer risks with maté consumption enhances the understanding of the public health consequences given its purported health benefits. PMID:24130226

  17. Risk Factors for Human Immunodeficiency Virus Infection among Brazilian Blood Donors; a Multicenter Case-Control Study Using Audio Computer-Assisted Structured-Interviews

    PubMed Central

    de Almeida-Neto, Cesar; Goncalez, Thelma T.; Birch, Rebecca Jeffries; de Carvalho, Silvia Maia F.; Capuani, Ligia; Leão, Silvana Carneiro; Miranda, Carolina; Rocha, Pedro Capuani; Carneiro-Proietti, Anna Barbara; Johnson, Bryce R.; Wright, David J.; Murphy, Edward L.; Custer, Brian

    2013-01-01

    Background Although risk factors for HIV infection are known, it is important for blood centers to understand local epidemiology and disease transmission patterns. Current risk factors for HIV infection in blood donors in Brazil were assessed. Methods A case-control study was conducted at large public blood centers located in four major cities between April 2009 – March 2011. Cases were persons whose donations were confirmed positive by enzyme immunoassays followed by Western Blot confirmation. Audio computer-assisted structured-interviews (ACASI) were completed by all cases and controls. Multivariable logistic regression was used to estimate adjusted odds ratios (AORs) and associated 95% confidence intervals (CIs). Results There were 341 cases, including 47 with recently-acquired infection, and 791 controls. Disclosed risk factors for both females and males were sex with an HIV-positive person (adjusted odds ratio (AOR) 11.3, 95% CI [4.1, 31.7]) and being an IVDU or sexual partner of an IVDU (AOR 4.65 [1.8, 11.7]). For female blood donors, additional risk factors were having male sex partners who also are MSM (AOR 13.5 [3.1, 59.8]), and having unprotected sex with multiple sexual partners (AOR 5.19 [2.1, 12.9]). The primary risk factor for male blood donors was MSM activity (AOR 21.6 [8.8, 52.9.]). Behaviors associated with recently-acquired HIV were being a MSM or sex partner of MSM (13.82, [4.7, 40.3]), and IVDU (11.47, [3.0, 43.2]). Conclusion Risk factors in blood donors parallel those in the general population in Brazil. Identified risk factors suggest that donor compliance with selection procedures at the participating blood centers is inadequate. PMID:23517235

  18. Risk factors for bloodstream infections due to colistin-resistant KPC-producing Klebsiella pneumoniae: results from a multicenter case-control-control study.

    PubMed

    Giacobbe, D R; Del Bono, V; Trecarichi, E M; De Rosa, F G; Giannella, M; Bassetti, M; Bartoloni, A; Losito, A R; Corcione, S; Bartoletti, M; Mantengoli, E; Saffioti, C; Pagani, N; Tedeschi, S; Spanu, T; Rossolini, G M; Marchese, A; Ambretti, S; Cauda, R; Viale, P; Viscoli, C; Tumbarello, M

    2015-12-01

    The increasing prevalence of colistin resistance (ColR) Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae (Kp) is a matter of concern because of its unfavourable impact on mortality of KPC-Kp bloodstream infections (BSI) and the shortage of alternative therapeutic options. A matched case-control-control analysis was conducted. The primary study end point was to assess risk factors for ColR KPC-Kp BSI. The secondary end point was to describe mortality and clinical characteristics of these infections. To assess risk factors for ColR, 142 patients with ColR KPC-Kp BSI were compared to two controls groups: 284 controls without infections caused by KPC-Kp (control group A) and 284 controls with colistin-susceptible (ColS) KPC-Kp BSI (control group B). In the first multivariate analysis (cases vs. group A), previous colistin therapy, previous KPC-Kp colonization, ≥3 previous hospitalizations, Charlson score ≥3 and neutropenia were found to be associated with the development of ColR KPC-Kp BSI. In the second multivariate analysis (cases vs. group B), only previous colistin therapy, previous KPC-Kp colonization and Charlson score ≥3 were associated with ColR. Overall, ColR among KPC-Kp blood isolates increased more than threefold during the 4.5-year study period, and 30-day mortality of ColR KPC-Kp BSI was as high as 51%. Strict rules for the use of colistin are mandatory to staunch the dissemination of ColR in KPC-Kp-endemic hospitals.

  19. Clinical utility of simultaneous measurement of alpha-fetoprotein and des-γ-carboxy prothrombin for diagnosis of patients with hepatocellular carcinoma in China: A multi-center case-controlled study of 1,153 subjects.

    PubMed

    Song, Peipei; Feng, Xiaobin; Inagaki, Yoshinori; Song, Tianqiang; Zhang, Keming; Wang, Zhigang; Zheng, Shuguo; Ma, Kuansheng; Li, Qiang; Kong, Dalu; Wu, Qiang; Zhang, Ti; Zhao, Xin; Hasegawa, Kiyoshi; Sugawara, Yasuhiko; Kokudo, Norihiro; Tang, Wei

    2014-10-01

    This study aimed to investigate the clinical utility of simultaneous measurement of alphafetoprotein (AFP) and des-γ-carboxy prothrombin (DCP) for hepatocellular carcinoma (HCC) diagnosis in Chinese patients predominantly caused by hepatitis B virus infection by a multi-center case-controlled study. Subjects were 1,153 individuals from three major hospitals in China, including 550 cases in HCC group, 164 in Malignant disease group, 182 in Benign disease group, 85 in Chronic liver disease group, and 173 in Normal group. Serum levels of AFP and DCP were measured and clinicopathological features were determined for all subjects. Results showed that the levels of DCP and AFP were significantly higher in HCC group (550 patients, 74.18% with HBV infection) than that in other four groups (P < 0.001). Receiver operating curves (ROC) indicated the optimal cut-off value was 86 mAU/mL for DCP with a sensitivity of 71.50% and specificity of 86.30%, and 21 ng/mL for AFP with a sensitivity of 68.00% and specificity of 93.20%. The area under ROC curve was 0.846 for DCP, 0.832 for AFP, and 0.890 for the combination of DCP and AFP. The combination of DCP and AFP resulted in a higher Youden index and a sensitivity of approximately 90%, even for small tumors. The simultaneous measurement of AFP and DCP could achieve a better sensitivity in diagnosing Chinese HCC patients, even for small tumors. PMID:25382443

  20. Sanitation and Hygiene-Specific Risk Factors for Moderate-to-Severe Diarrhea in Young Children in the Global Enteric Multicenter Study, 2007–2011: Case-Control Study

    PubMed Central

    O’Reilly, Ciara E.; Levine, Myron M.; Kotloff, Karen L.; Farag, Tamer H.; Nasrin, Dilruba; Alonso, Pedro L.; Breiman, Robert F.; Omore, Richard; Faruque, Abu S. G.; Das, Sumon Kumar; Ahmed, Shahnawaz; Saha, Debasish; Sow, Samba O.; Sur, Dipika; Zaidi, Anita K. M.; Quadri, Fahreen; Mintz, Eric D.

    2016-01-01

    Background Diarrheal disease is the second leading cause of disease in children less than 5 y of age. Poor water, sanitation, and hygiene conditions are the primary routes of exposure and infection. Sanitation and hygiene interventions are estimated to generate a 36% and 48% reduction in diarrheal risk in young children, respectively. Little is known about whether the number of households sharing a sanitation facility affects a child's risk of diarrhea. The objective of this study was to describe sanitation and hygiene access across the Global Enteric Multicenter Study (GEMS) sites in Africa and South Asia and to assess sanitation and hygiene exposures, including shared sanitation access, as risk factors for moderate-to-severe diarrhea (MSD) in children less than 5 y of age. Methods/Findings The GEMS matched case-control study was conducted between December 1, 2007, and March 3, 2011, at seven sites in Basse, The Gambia; Nyanza Province, Kenya; Bamako, Mali; Manhiça, Mozambique; Mirzapur, Bangladesh; Kolkata, India; and Karachi, Pakistan. Data was collected for 8,592 case children aged <5 y old experiencing MSD and for 12,390 asymptomatic age, gender, and neighborhood-matched controls. An MSD case was defined as a child with a diarrheal illness <7 d duration comprising ≥3 loose stools in 24 h and ≥1 of the following: sunken eyes, skin tenting, dysentery, intravenous (IV) rehydration, or hospitalization. Site-specific conditional logistic regression models were used to explore the association between sanitation and hygiene exposures and MSD. Most households at six sites (>93%) had access to a sanitation facility, while 70% of households in rural Kenya had access to a facility. Practicing open defecation was a risk factor for MSD in children <5 y old in Kenya. Sharing sanitation facilities with 1–2 or ≥3 other households was a statistically significant risk factor for MSD in Kenya, Mali, Mozambique, and Pakistan. Among those with a designated handwashing

  1. The impact of exposure-biased sampling designs on detection of gene-environment interactions in case-control studies with potential exposure misclassification.

    PubMed

    Stenzel, Stephanie L; Ahn, Jaeil; Boonstra, Philip S; Gruber, Stephen B; Mukherjee, Bhramar

    2015-05-01

    With limited funding and biological specimen availability, choosing an optimal sampling design to maximize power for detecting gene-by-environment (G-E) interactions is critical. Exposure-enriched sampling is often used to select subjects with rare exposures for genotyping to enhance power for tests of G-E effects. However, exposure misclassification (MC) combined with biased sampling can affect characteristics of tests for G-E interaction and joint tests for marginal association and G-E interaction. Here, we characterize the impact of exposure-biased sampling under conditions of perfect exposure information and exposure MC on properties of several methods for conducting inference. We assess the Type I error, power, bias, and mean squared error properties of case-only, case-control, and empirical Bayes methods for testing/estimating G-E interaction and a joint test for marginal G (or E) effect and G-E interaction across three biased sampling schemes. Properties are evaluated via empirical simulation studies. With perfect exposure information, exposure-enriched sampling schemes enhance power as compared to random selection of subjects irrespective of exposure prevalence but yield bias in estimation of the G-E interaction and marginal E parameters. Exposure MC modifies the relative performance of sampling designs when compared to the case of perfect exposure information. Those conducting G-E interaction studies should be aware of exposure MC properties and the prevalence of exposure when choosing an ideal sampling scheme and method for characterizing G-E interactions and joint effects.

  2. How Many Samples and How Many Culture Media To Diagnose a Prosthetic Joint Infection: a Clinical and Microbiological Prospective Multicenter Study

    PubMed Central

    Léger, Julie; Tandé, Didier; Plouzeau, Chloé; Valentin, Anne Sophie; Jolivet-Gougeon, Anne; Lemarié, Carole; Kempf, Marie; Héry-Arnaud, Geneviève; Bret, Laurent; Juvin, Marie Emmanuelle; Giraudeau, Bruno; Burucoa, Christophe

    2015-01-01

    Although numerous perioperative samples and culture media are required to diagnose prosthetic joint infection (PJI), their exact number and types have not yet been definitely determined with a high level of proof. We conducted a prospective multicenter study to determine the minimal number of samples and culture media required for accurate diagnosis of PJI. Over a 2-year period, consecutive patients with clinical signs suggesting PJI were included, with five perioperative samples per patient. The bacteriological and PJI diagnosis criteria were assessed using a random selection of two, three, or four samples and compared with those obtained using the recommended five samples (references guidelines). The results obtained with two or three culture media were then compared with those obtained with five culture media for both criteria. The times-to-positivity of the different culture media were calculated. PJI was confirmed in 215/264 suspected cases, with a bacteriological criterion in 192 (89%). The PJI was monomicrobial (85%) or polymicrobial (15%). Percentages of agreement of 98.1% and 99.7%, respectively, for the bacteriological criterion and confirmed PJI diagnosis were obtained when four perioperative samples were considered. The highest percentages of agreement were obtained with the association of three culture media, a blood culture bottle, a chocolate agar plate, and Schaedler broth, incubated for 5, 7, and 14 days, respectively. This new procedure leads to significant cost saving. Our prospective multicenter study showed that four samples seeded on three culture media are sufficient for diagnosing PJI. PMID:26637380

  3. How Many Samples and How Many Culture Media To Diagnose a Prosthetic Joint Infection: a Clinical and Microbiological Prospective Multicenter Study.

    PubMed

    Bémer, Pascale; Léger, Julie; Tandé, Didier; Plouzeau, Chloé; Valentin, Anne Sophie; Jolivet-Gougeon, Anne; Lemarié, Carole; Kempf, Marie; Héry-Arnaud, Geneviève; Bret, Laurent; Juvin, Marie Emmanuelle; Giraudeau, Bruno; Corvec, Stéphane; Burucoa, Christophe

    2016-02-01

    Although numerous perioperative samples and culture media are required to diagnose prosthetic joint infection (PJI), their exact number and types have not yet been definitely determined with a high level of proof. We conducted a prospective multicenter study to determine the minimal number of samples and culture media required for accurate diagnosis of PJI. Over a 2-year period, consecutive patients with clinical signs suggesting PJI were included, with five perioperative samples per patient. The bacteriological and PJI diagnosis criteria were assessed using a random selection of two, three, or four samples and compared with those obtained using the recommended five samples (references guidelines). The results obtained with two or three culture media were then compared with those obtained with five culture media for both criteria. The times-to-positivity of the different culture media were calculated. PJI was confirmed in 215/264 suspected cases, with a bacteriological criterion in 192 (89%). The PJI was monomicrobial (85%) or polymicrobial (15%). Percentages of agreement of 98.1% and 99.7%, respectively, for the bacteriological criterion and confirmed PJI diagnosis were obtained when four perioperative samples were considered. The highest percentages of agreement were obtained with the association of three culture media, a blood culture bottle, a chocolate agar plate, and Schaedler broth, incubated for 5, 7, and 14 days, respectively. This new procedure leads to significant cost saving. Our prospective multicenter study showed that four samples seeded on three culture media are sufficient for diagnosing PJI.

  4. How Many Samples and How Many Culture Media To Diagnose a Prosthetic Joint Infection: a Clinical and Microbiological Prospective Multicenter Study.

    PubMed

    Bémer, Pascale; Léger, Julie; Tandé, Didier; Plouzeau, Chloé; Valentin, Anne Sophie; Jolivet-Gougeon, Anne; Lemarié, Carole; Kempf, Marie; Héry-Arnaud, Geneviève; Bret, Laurent; Juvin, Marie Emmanuelle; Giraudeau, Bruno; Corvec, Stéphane; Burucoa, Christophe

    2016-02-01

    Although numerous perioperative samples and culture media are required to diagnose prosthetic joint infection (PJI), their exact number and types have not yet been definitely determined with a high level of proof. We conducted a prospective multicenter study to determine the minimal number of samples and culture media required for accurate diagnosis of PJI. Over a 2-year period, consecutive patients with clinical signs suggesting PJI were included, with five perioperative samples per patient. The bacteriological and PJI diagnosis criteria were assessed using a random selection of two, three, or four samples and compared with those obtained using the recommended five samples (references guidelines). The results obtained with two or three culture media were then compared with those obtained with five culture media for both criteria. The times-to-positivity of the different culture media were calculated. PJI was confirmed in 215/264 suspected cases, with a bacteriological criterion in 192 (89%). The PJI was monomicrobial (85%) or polymicrobial (15%). Percentages of agreement of 98.1% and 99.7%, respectively, for the bacteriological criterion and confirmed PJI diagnosis were obtained when four perioperative samples were considered. The highest percentages of agreement were obtained with the association of three culture media, a blood culture bottle, a chocolate agar plate, and Schaedler broth, incubated for 5, 7, and 14 days, respectively. This new procedure leads to significant cost saving. Our prospective multicenter study showed that four samples seeded on three culture media are sufficient for diagnosing PJI. PMID:26637380

  5. Moving into a new era of periodontal genetic studies: relevance of large case-control samples using severe phenotypes for genome-wide association studies.

    PubMed

    Vaithilingam, R D; Safii, S H; Baharuddin, N A; Ng, C C; Cheong, S C; Bartold, P M; Schaefer, A S; Loos, B G

    2014-12-01

    Studies to elucidate the role of genetics as a risk factor for periodontal disease have gone through various phases. In the majority of cases, the initial 'hypothesis-dependent' candidate-gene polymorphism studies did not report valid genetic risk loci. Following a large-scale replication study, these initially positive results are believed to be caused by type 1 errors. However, susceptibility genes, such as CDKN2BAS (Cyclin Dependend KiNase 2B AntiSense RNA; alias ANRIL [ANtisense Rna In the Ink locus]), glycosyltransferase 6 domain containing 1 (GLT6D1) and cyclooxygenase 2 (COX2), have been reported as conclusive risk loci of periodontitis. The search for genetic risk factors accelerated with the advent of 'hypothesis-free' genome-wide association studies (GWAS). However, despite many different GWAS being performed for almost all human diseases, only three GWAS on periodontitis have been published - one reported genome-wide association of GLT6D1 with aggressive periodontitis (a severe phenotype of periodontitis), whereas the remaining two, which were performed on patients with chronic periodontitis, were not able to find significant associations. This review discusses the problems faced and the lessons learned from the search for genetic risk variants of periodontitis. Current and future strategies for identifying genetic variance in periodontitis, and the importance of planning a well-designed genetic study with large and sufficiently powered case-control samples of severe phenotypes, are also discussed. PMID:24528298

  6. Evidence for schizophrenia susceptibility alleles in the Indian population: An association of neurodevelopmental genes in case-control and familial samples.

    PubMed

    Jajodia, Ajay; Kaur, Harpreet; Kumari, Kalpana; Gupta, Meenal; Baghel, Ruchi; Srivastava, Ankit; Sood, Mamta; Chadda, Rakesh Kumar; Jain, Sanjeev; Kukreti, Ritushree

    2015-03-01

    Schizophrenia is a severe psychiatric disorder with lifetime prevalence of ~1% worldwide. A genotyping study was conducted using a custom panel of Illumina 1536 SNPs in 840 schizophrenia cases and 876 controls (351 patients and 385 controls from North India; and 436 patients, 401 controls and 143 familial samples with 53 probands containing 37 complete and 16 incomplete trios from South India). Meta-analysis of this population of Indo-European and Dravidian ancestry identified three strongly associated variants with schizophrenia: STT3A (rs548181, p=1.47×10(-5)), NRG1 (rs17603876, p=8.66×10(-5)) and GRM7 (rs3864075, p=4.06×10(-3)). Finally, a meta-analysis was conducted comparing our data with data from the Schizophrenia Psychiatric Genome-Wide Association Study Consortium (PGC-SCZ) that supported rs548181 (p=1.39×10(-7)). In addition, combined analysis of sporadic case-control association and a transmission disequilibrium test in familial samples from South Indian population identified three associations: rs1062613 (p=3.12×10(-3)), a functional promoter variant of HTR3A; rs6710782 (p=3.50×10(-3)), an intronic variant of ERBB4; and rs891903 (p=1.05×10(-2)), an intronic variant of EBF1. The results support the risk variants observed in the earlier published work and suggest a potential role of neurodevelopmental genes in the schizophrenia pathogenesis.

  7. Oral Bisphosphonates and Upper Gastrointestinal Cancer Risks in Asians with Osteoporosis: A Nested Case-Control Study Using National Retrospective Cohort Sample Data from Korea

    PubMed Central

    Park, Eun-Ja; Suh, Hae Sun; Park, Ji-Won; Kwon, Jin-Won

    2016-01-01

    Background Bisphosphonate can irritate the gastrointestinal mucosa and increase the risk of esophageal or gastric cancer. The relatively high prevalence of upper gastrointestinal cancers and the widespread use of bisphosphonate in Korea call for further investigation. We conducted a case-control study to evaluate the risk of esophageal or gastric cancer after exposure to oral bisphosphonates in Korean patients with osteoporosis. Methods We used the National Health Insurance Service-National Sample Cohort database of Korea from 2002 to 2013. Among osteoporotic patients (>40 years), cases were defined as incident diagnosis of esophageal or gastric cancer between 2006 and 2013. For each case, four controls were matched for age, sex, and income level by type of insurance. We categorized bisphosphonate use as non-user, recent user, past user, and past and recent user, depending on prescription in two periods (1 to 2 years and 2 to 4 years prior to the index date). We also assessed the duration of bisphosphonate use by measuring cumulative duration of exposure (CDE). To examine the association between oral bisphosphonates and esophageal or gastric cancer, we estimated adjusted odds ratios (aORs) and 95% confidence intervals (CIs) using conditional logistic regression analysis, adjusting for concomitant diseases. Results A total of 1,708 cases and 6,832 controls were identified. The aORs (95% CIs) of recent, past, and continuous bisphosphonate use compared to non-users were 1.18 (0.93–1.51), 1.04 (0.83–1.29), and 1.25 (0.95–1.58)), respectively. In addition, no significant association was observed by CDE, even when different outcome definitions were applied. Conclusions This study did not prove an increased risk of esophageal or gastric cancer risk associated with bisphosphonate use, with respect to both risk windows and duration of exposure, in an Asian population-based, real-world setting. PMID:26937968

  8. Power and sample size calculations for case-control genetic association tests when errors are present: application to single nucleotide polymorphisms.

    PubMed

    Gordon, Derek; Finch, Stephen J; Nothnagel, Michael; Ott, Jürg

    2002-01-01

    The purpose of this work is to quantify the effects that errors in genotyping have on power and the sample size necessary to maintain constant asymptotic Type I and Type II error rates (SSN) for case-control genetic association studies between a disease phenotype and a di-allelic marker locus, for example a single nucleotide polymorphism (SNP) locus. We consider the effects of three published models of genotyping errors on the chi-square test for independence in the 2 x 3 table. After specifying genotype frequencies for the marker locus conditional on disease status and error model in both a genetic model-based and a genetic model-free framework, we compute the asymptotic power to detect association through specification of the test's non-centrality parameter. This parameter determines the functional dependence of SSN on the genotyping error rates. Additionally, we study the dependence of SSN on linkage disequilibrium (LD), marker allele frequencies, and genotyping error rates for a dominant disease model. Increased genotyping error rate requires a larger SSN. Every 1% increase in sum of genotyping error rates requires that both case and control SSN be increased by 2-8%, with the extent of increase dependent upon the error model. For the dominant disease model, SSN is a nonlinear function of LD and genotyping error rate, with greater SSN for lower LD and higher genotyping error rate. The combination of lower LD and higher genotyping error rates requires a larger SSN than the sum of the SSN for the lower LD and for the higher genotyping error rate.

  9. The Effects of Dinner-to-Bed Time and Post-Dinner Walk on Gastric Cancer Across Different Age Groups: A Multicenter Case-Control Study in Southeast China.

    PubMed

    Xu, Le; Zhang, Xi; Lu, Jun; Dai, Jia-Xi; Lin, Ren-Qin; Tian, Fang-Xi; Liang, Bing; Guo, Yi-Nan; Luo, Hui-Yu; Li, Ni; Fang, Dong-Ping; Zhao, Ruo-Hua; Huang, Chang-Ming

    2016-04-01

    Gastric cancer (GC) remains a major killer throughout the world. Despite the dramatic decrease in GC over the last century, its etiology has not yet been well characterized. This study investigated the possible independent and combined effects of the dinner-to-bed time and post-dinner walk on the risk for GC across different age groups. A population-based, case-control study was conducted in southeast China, including 452 patients with GC and 465 age-, race-, and gender-matched controls. A self-designed questionnaire was used to collect information on demographic characteristics, dinner-to-bed time, post-dinner walk, and other behavioral factors. Conditional logistic regression models were used to estimate the effects of the dinner-to-bed time and post-dinner walk as well as their joint effect on the risk for GC across different age groups. Individuals with dinner-to-bed time <3 hours were more prone to have GC (P < 0.001), and the shorter the dinner-to-bed time was, the higher was the risk for GC (Ptrend < 0.001). Post-dinner nonwalk was associated with a 2.9-fold increased risk for GC compared with post-dinner walk (adjusted odds ratio [AOR] = 2.942, 95% confidence intervals [95% CIs] = 2.072-4.179). The interaction effect of dinner-to-bed time and post-dinner walk on GC risk was detected (AOR = 1.862, 95% CIs = 1.584-3.885, synergy index [SI] = 2.654, 95% CIs = 2.27-3.912). Participants with dinner-to-bed time <3 hours who did not walk after dinner were 7.4 times likely to suffer from GC (AOR = 7.401, 95% CIs = 4.523-13.16) than those with dinner-to-bed time ≥4 hours who took such walk. The risk of GC due to dinner-to-bed time <3 hours, post-dinner nonwalk and their interaction was positively correlated with age. The strongest risk was observed among people ≥70 years old, but the effects were not significant for people ≤55 years old. Dinner-to-bed time <3 hours and post-dinner nonwalk are independent risk

  10. [A case-control study of factors associated with repeat teen pregnancy based on a sample from a university maternity hospital].

    PubMed

    Silva, Andréa de Albuquerque Arruda; Coutinho, Isabela C; Katz, Leila; Souza, Alex Sandro Rolland

    2013-03-01

    Repeat teen pregnancy is a frequent issue and is considered an aggravating factor for increased maternal and fetal morbidity and social problems. The aim of the study was to identify factors associated with repeat teen pregnancy. A case-control study was conducted in 90 postpartum adolescents with more than one pregnancy (cases) and 90 adult women with a history of only one pregnancy during adolescence (controls). Statistical analysis used hierarchical logistic regression with 5% significance. Early sexual initiation (< 15 years), early age at first pregnancy (< 16 years), not raising the children themselves, and low family income (< one minimum wage) were associated with repeat teenage pregnancy, while partner change was inversely associated. Repeat teen pregnancy was mainly associated with reproductive and socioeconomic factors. Partner change appeared as a protective factor. Measures should be adopted during the postpartum period of teenage mothers in order to avoid repeat pregnancy.

  11. Recalled Initiation and Duration of Maternal Breastfeeding Among Children with and Without ADHD in a Well Characterized Case-Control Sample.

    PubMed

    Stadler, Diane D; Musser, Erica D; Holton, Kathleen F; Shannon, Jackilen; Nigg, Joel T

    2016-02-01

    Early environmental influences are increasingly of interest in understanding ADHD as a neurodevelopmental condition, particularly in light of recognition that gene by environment interplay are likely involved in this condition. Breastfeeding duration predicts cognitive development, as well as development of brain white matter connectivity, in areas similar to those seen in ADHD. Prior studies show an association between breastfeeding and ADHD but without adequate evaluation of ADHD. A case control cohort of 474 children aged 7-13 years was examined, 291 with well characterized ADHD (71.5 % male) and the rest typically developing controls (51.9 % male). Mothers retrospectively reported on breast feeding initiation and duration. Initiation of breastfeeding was not associated with child ADHD, but shorter duration of breastfeeding was associated with child ADHD with a medium effect size (d = 0.40, p < 0.05); this effect held after covarying a broad set of potential confounders, including child oppositional defiant and conduct problems and including maternal and paternal ADHD symptoms. Effects were replicated across both parent and teacher ratings of child ADHD symptoms. Shorter duration of breastfeeding is among several risk factors in early life associated with future ADHD, or else longer duration is protective. The direction of this effect is unknown, however. It may be that some children are more difficult to breastfeed or that breastfeeding provides nutrients or other benefits that reduce future chance of ADHD. PMID:25749651

  12. Genetic variations in the CLNK gene and ZNF518B gene are associated with gout in case-control sample sets.

    PubMed

    Jin, Tian-Bo; Ren, Yongchao; Shi, Xugang; Jiri, Mutu; He, Na; Feng, Tian; Yuan, Dongya; Kang, Longli

    2015-07-01

    A genome-wide association study of gout in European populations identified 12 genetic variants strongly associated with risk of gout, but it is unknown whether these variants are also associated with gout risk in Chinese populations. A total of 145 patients with gout and 310 healthy control patients were recruited for a case-control association study. Twelve SNPs of CLNK and ZNF518B gene were genotyped, and association analysis was performed. Odds ratios (ORs) with 95 % confidence intervals (CIs) were used to assess the association. Overall, we found four risk alleles for gout in patients: the allele "G" of rs2041215 and rs1686947 in the CLNK gene by dominant model (OR 1.66; 95 % CI 1.04-2.63; p = 0.031) (OR 2.19; 95 % CI 1.38-3.46; p = 0.001) and additive model (OR 1.39; 95 % CI 1.00-1.93; p = 0.049) (OR 1.67; 95 % CI 1.19-2.32; p = 0.003), respectively, and the allele "A" of rs10938799 and rs10016022 in ZNF518B gene by recessive model (OR 4.66; 95 % CI 1.44-15.09; p = 0.008) (OR 4.54; 95 % CI 1.23-16.76; p = 0.020). Further haplotype analysis showed that the TCATTCTGA haplotype of CLNK was more frequent among patients with gout (adjusted OR 0.48; 95 % CI 0.24-0.95; p = 0.036). Additionally, polymorphisms of rs2041215, rs10938799, and rs17467273 were also correlated with clinical pathological parameters. This study provides evidence for gout susceptibility genes, CLNK and ZNF518B, in a Chinese population, which may have potential as diagnostic and prognostic marker for gout patients.

  13. Optimal Unified Approach for Rare-Variant Association Testing with Application to Small-Sample Case-Control Whole-Exome Sequencing Studies

    PubMed Central

    Lee, Seunggeun; Emond, Mary J.; Bamshad, Michael J.; Barnes, Kathleen C.; Rieder, Mark J.; Nickerson, Deborah A.; Christiani, David C.; Wurfel, Mark M.; Lin, Xihong

    2012-01-01

    We propose in this paper a unified approach for testing the association between rare variants and phenotypes in sequencing association studies. This approach maximizes power by adaptively using the data to optimally combine the burden test and the nonburden sequence kernel association test (SKAT). Burden tests are more powerful when most variants in a region are causal and the effects are in the same direction, whereas SKAT is more powerful when a large fraction of the variants in a region are noncausal or the effects of causal variants are in different directions. The proposed unified test maintains the power in both scenarios. We show that the unified test corresponds to the optimal test in an extended family of SKAT tests, which we refer to as SKAT-O. The second goal of this paper is to develop a small-sample adjustment procedure for the proposed methods for the correction of conservative type I error rates of SKAT family tests when the trait of interest is dichotomous and the sample size is small. Both small-sample-adjusted SKAT and the optimal unified test (SKAT-O) are computationally efficient and can easily be applied to genome-wide sequencing association studies. We evaluate the finite sample performance of the proposed methods using extensive simulation studies and illustrate their application using the acute-lung-injury exome-sequencing data of the National Heart, Lung, and Blood Institute Exome Sequencing Project. PMID:22863193

  14. CERAMIC: Case-Control Association Testing in Samples with Related Individuals, Based on Retrospective Mixed Model Analysis with Adjustment for Covariates

    PubMed Central

    Zhong, Sheng; McPeek, Mary Sara

    2016-01-01

    We consider the problem of genetic association testing of a binary trait in a sample that contains related individuals, where we adjust for relevant covariates and allow for missing data. We propose CERAMIC, an estimating equation approach that can be viewed as a hybrid of logistic regression and linear mixed-effects model (LMM) approaches. CERAMIC extends the recently proposed CARAT method to allow samples with related individuals and to incorporate partially missing data. In simulations, we show that CERAMIC outperforms existing LMM and generalized LMM approaches, maintaining high power and correct type 1 error across a wider range of scenarios. CERAMIC results in a particularly large power increase over existing methods when the sample includes related individuals with some missing data (e.g., when some individuals with phenotype and covariate information have missing genotype), because CERAMIC is able to make use of the relationship information to incorporate partially missing data in the analysis while correcting for dependence. Because CERAMIC is based on a retrospective analysis, it is robust to misspecification of the phenotype model, resulting in better control of type 1 error and higher power than that of prospective methods, such as GMMAT, when the phenotype model is misspecified. CERAMIC is computationally efficient for genomewide analysis in samples of related individuals of almost any configuration, including small families, unrelated individuals and even large, complex pedigrees. We apply CERAMIC to data on type 2 diabetes (T2D) from the Framingham Heart Study. In a genome scan, 9 of the 10 smallest CERAMIC p-values occur in or near either known T2D susceptibility loci or plausible candidates, verifying that CERAMIC is able to home in on the important loci in a genome scan. PMID:27695091

  15. Large-Scale Prospective T Cell Function Assays in Shipped, Unfrozen Blood Samples: Experiences from the Multicenter TRIGR Trial

    PubMed Central

    Cheung, Roy K.; Becker, Dorothy J.; Girgis, Rose; Palmer, Jerry P.; Cuthbertson, David; Krischer, Jeffrey P.

    2014-01-01

    Broad consensus assigns T lymphocytes fundamental roles in inflammatory, infectious, and autoimmune diseases. However, clinical investigations have lacked fully characterized and validated procedures, equivalent to those of widely practiced biochemical tests with established clinical roles, for measuring core T cell functions. The Trial to Reduce Insulin-dependent diabetes mellitus in the Genetically at Risk (TRIGR) type 1 diabetes prevention trial used consecutive measurements of T cell proliferative responses in prospectively collected fresh heparinized blood samples shipped by courier within North America. In this article, we report on the quality control implications of this simple and pragmatic shipping practice and the interpretation of positive- and negative-control analytes in our assay. We used polyclonal and postvaccination responses in 4,919 samples to analyze the development of T cell immunocompetence. We have found that the vast majority of the samples were viable up to 3 days from the blood draw, yet meaningful responses were found in a proportion of those with longer travel times. Furthermore, the shipping time of uncooled samples significantly decreased both the viabilities of the samples and the unstimulated cell counts in the viable samples. Also, subject age was significantly associated with the number of unstimulated cells and T cell proliferation to positive activators. Finally, we observed a pattern of statistically significant increases in T cell responses to tetanus toxin around the timing of infant vaccinations. This assay platform and shipping protocol satisfy the criteria for robust and reproducible long-term measurements of human T cell function, comparable to those of established blood biochemical tests. We present a stable technology for prospective disease-relevant T cell analysis in immunological diseases, vaccination medicine, and measurement of herd immunity. PMID:24334687

  16. Comparison of Address-based Sampling and Random-digit Dialing Methods for Recruiting Young Men as Controls in a Case-Control Study of Testicular Cancer Susceptibility

    PubMed Central

    Clagett, Bartholt; Nathanson, Katherine L.; Ciosek, Stephanie L.; McDermoth, Monique; Vaughn, David J.; Mitra, Nandita; Weiss, Andrew; Martonik, Rachel; Kanetsky, Peter A.

    2013-01-01

    Random-digit dialing (RDD) using landline telephone numbers is the historical gold standard for control recruitment in population-based epidemiologic research. However, increasing cell-phone usage and diminishing response rates suggest that the effectiveness of RDD in recruiting a random sample of the general population, particularly for younger target populations, is decreasing. In this study, we compared landline RDD with alternative methods of control recruitment, including RDD using cell-phone numbers and address-based sampling (ABS), to recruit primarily white men aged 18–55 years into a study of testicular cancer susceptibility conducted in the Philadelphia, Pennsylvania, metropolitan area between 2009 and 2012. With few exceptions, eligible and enrolled controls recruited by means of RDD and ABS were similar with regard to characteristics for which data were collected on the screening survey. While we find ABS to be a comparably effective method of recruiting young males compared with landline RDD, we acknowledge the potential impact that selection bias may have had on our results because of poor overall response rates, which ranged from 11.4% for landline RDD to 1.7% for ABS. PMID:24008901

  17. Designing case-control studies.

    PubMed Central

    Yanagawa, T

    1979-01-01

    Identification of confounding factors, evaluation of their influence on cause-effect associations, and the introduction of appropriate ways to account for these factors are important considerations in designing case-control studies. This paper presents designs useful for these purposes, after first providing a statistical definition of a confounding factor. Differences in the ability to identify and evaluate confounding factors and estimate disease risk between designs employing stratification (matching) and designs randomly sampling cases and controls are noted. Linear logistic models for the analysis of data from such designs are described and are shown to liberalize design requirements and to increase relative risk estimation efficiency. The methods are applied to data from a multiple factor investigation of lung cancer patients and controls. PMID:540588

  18. Calibration and seasonal adjustment for matched case-control studies of vitamin D and cancer.

    PubMed

    Gail, Mitchell H; Wu, Jincao; Wang, Molin; Yaun, Shiaw-Shyuan; Cook, Nancy R; Eliassen, A Heather; McCullough, Marjorie L; Yu, Kai; Zeleniuch-Jacquotte, Anne; Smith-Warner, Stephanie A; Ziegler, Regina G; Carroll, Raymond J

    2016-06-15

    Vitamin D measurements are influenced by seasonal variation and specific assay used. Motivated by multicenter studies of associations of vitamin D with cancer, we formulated an analytic framework for matched case-control data that accounts for seasonal variation and calibrates to a reference assay. Calibration data were obtained from controls sampled within decile strata of the uncalibrated vitamin D values. Seasonal sine-cosine series were fit to control data. Practical findings included the following: (1) failure to adjust for season and calibrate increased variance, bias, and mean square error and (2) analysis of continuous vitamin D requires a variance adjustment for variation in the calibration estimate. An advantage of the continuous linear risk model is that results are independent of the reference date for seasonal adjustment. (3) For categorical risk models, procedures based on categorizing the seasonally adjusted and calibrated vitamin D have near nominal operating characteristics; estimates of log odds ratios are not robust to choice of seasonal reference date, however. Thus, public health recommendations based on categories of vitamin D should also define the time of year to which they refer. This work supports the use of simple methods for calibration and seasonal adjustment and is informing analytic approaches for the multicenter Vitamin D Pooling Project for Breast and Colorectal Cancer. Published 2016. This article has been contributed to by US Government employees and their work is in the public domain in the USA. PMID:27133461

  19. Nasopharyngeal Case-Control Study

    Cancer.gov

    A case-control study conducted in Taiwan between 1991-1994 among approximately 1,000 individuals to examine the role of viral, environmental, and genetic factors associated with the development of nasopharyngeal carcinoma

  20. A Cladistic Analysis of Phenotypic Associations with Haplotypes Inferred from Restriction Endonuclease Mapping or DNA Sequencing. V. Analysis of Case/Control Sampling Designs: Alzheimer's Disease and the Apoprotein E Locus

    PubMed Central

    Templeton, A. R.

    1995-01-01

    Present-day associations between haplotypes at a candidate locus and phenotypes exist when phenotypically important mutations occurred at some point during the evolution of the current array of genetic variation. A cladistic statistical design can be defined that focuses power by using the evolutionary history of the candidate DNA region. This paper shows how cladistic methodology is used for the analysis of case/control data, a common sampling design in genetic/disease association studies. A worked example is presented of the associations for sporadic early and late-onset forms of Alzheimer's disease with the 19q13.2 chromosomal region that includes the loci for apoproteins E, CI, and CII. This analysis confirms earlier reports of a strong association of the ApoE &4 allele with Alzheimer's disease but indicates that it is premature to condsider this association causal, particularly for early onset cases. Associations were also found with the &2 allele, as previously reported, and with the 1 allele at the ApoCI locus. However, this analysis indicates that it is inappropriate both statistically and medically to use single markers as risk predictors when haplotype data are available, even when the mutation leading to the marker is identified as having a strong phenotypic association. PMID:7635303

  1. Case-control study on analgesics and nephropathy (SAN): protocol

    PubMed Central

    Heinemann, Lothar AJ; Garbe, Edeltraut; Lewis, Michael; van der Woude, Fokko; Graf, Helmut

    2005-01-01

    Background The association between intake of non-phenacetin-containing analgesics and the occurrence of chronic renal failure is still controversially discussed. A new epidemiologic study was planned and conducted in Germany and Austria. Methods/design The objective of the international, multicenter case-control study was to evaluate the association between end-stage renal disease (ESRD) and use of non-phenacetin-containing analgesics with particular emphasis on combined formulations. A targeted sample of 1000 new (incident) dialysis patients, aged less than 50 years, was planned to recruit between January 1, 2001 and December 31, 2004. The age limit was chosen to avoid contamination of the study population with phenacetin-containing analgesics to the extent possible. Four control subjects per ESRD case, matched by age, sex, and region were selected from the population living in the region the case came from. Lifetime exposure to analgesics and potential renal risk factors were recorded in a single face-to-face interview. A set of aids was introduced to reinforce the memory of study participants. A standardized, pre-tested interview questionnaire (participants), a medical documentation sheet (physicians in dialysis centres), a logbook for all activities (dialysis centres) were used to collect the necessary data. Quality management consisted of the standardized procedures, (re-) training and supervision of interviewers, regular checks of all incoming data for completeness and plausibility. The study is scientifically independent and governed by a international Scientific Advisory Committee that bridged the gap between the sponsoring companies and the investigators. Also other advisory groups assisted the managing committee of the study. All relevant German and Austrian nephrological associations supported the study, and the study design was carefully reviewed and approved by the Kidney Foundation of Germany. Discussion The study is expected to answer the main

  2. Multicenter Patient Records Research

    PubMed Central

    Behlen, Fred M.; Johnson, Stephen B.

    1999-01-01

    The expanding health information infrastructure offers the promise of new medical knowledge drawn from patient records. Such promise will never be fulfilled, however, unless researchers first address policy issues regarding the rights and interests of both the patients and the institutions who hold their records. In this article, the authors analyze the interests of patients and institutions in light of public policy and institutional needs. They conclude that the multicenter study, with Institutional Review Board approval of each study at each site, protects the interests of both. “Anonymity” is no panacea, since patient records are so rich in information that they can never be truly anonymous. Researchers must earn and respect the trust of the public, as responsible stewards of facts about patients' lives. The authors find that computer security tools are needed to administer multicenter patient records studies and describe simple approaches that can be implemented using commercial database products. PMID:10579601

  3. 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…

  4. Periodontal conditions in patients with Marfan syndrome – a multicenter case control study

    PubMed Central

    2013-01-01

    Background Marfan syndrome (MFS) is a disorder of the connective tissues. Alterations of the elastic fibers may manifest in different tissues especially in the skeletal, cardiovascular and ocular system. Oral manifestations like orthodontic or skeletal anomalies and fragility of the temporomandibular joint have been well described by various authors. However, no data are available regarding a possible periodontal involvement of MFS. Hence, the aim of the present study was to investigate for the first time if MFS may increase the susceptibility to periodontitis. Methods A comprehensive periodontal examination including documentation of probing pocket depth, gingival recession, clinical attachment level, and bleeding on probing was conducted in all patients. In addition, dental conditions were assessed by determining the Index for Decayed, Missing and Filled Teeth (DMFT) and a self-administered questionnaire was filled out by patients. For statistical analysis, the unpaired t-Test was applied (level of significance: p < 0.05). Both groups were matched concerning well known periodontal risk factors like age, gender and smoking habits. Results 82 participants, 51 patients with MFS (30 female and 21 male, mean age: 40.20 ± 15.35 years) and 31 sound controls (17 female and 14 male, mean age: 40.29 ± 13.94 years), were examined. All assessed periodontal and dental parameters were not significantly different between groups. Conclusions Based on our data, patients with MFS did not reveal a higher prevalence of periodontitis compared to the control group. However, Marfan patients showed a tendency to more inflammation signs, which can be explained by the crowded teeth. Therefore, a regular professional cleaning of the teeth is recommendable (i.e., 6 months intervals) in order to reduce the bacterial biofilm in the oral cavity and thus resulting in a decreased risk of systemic diseases, specifically endocarditis. PMID:24165013

  5. Evaluation of a Minimally Invasive Cell Sampling Device Coupled with Assessment of Trefoil Factor 3 Expression for Diagnosing Barrett's Esophagus: A Multi-Center Case–Control Study

    PubMed Central

    Ross-Innes, Caryn S.; Debiram-Beecham, Irene; O'Donovan, Maria; Walker, Elaine; Varghese, Sibu; Lao-Sirieix, Pierre; Lovat, Laurence; Griffin, Michael; Ragunath, Krish; Haidry, Rehan; Sami, Sarmed S.; Kaye, Philip; Novelli, Marco; Disep, Babett; Ostler, Richard; Aigret, Benoit; North, Bernard V.; Bhandari, Pradeep; Haycock, Adam; Morris, Danielle; Attwood, Stephen; Dhar, Anjan; Rees, Colin; Rutter, Matthew D. D.; Sasieni, Peter D.; Fitzgerald, Rebecca C.

    2015-01-01

    Background Barrett's esophagus (BE) is a commonly undiagnosed condition that predisposes to esophageal adenocarcinoma. Routine endoscopic screening for BE is not recommended because of the burden this would impose on the health care system. The objective of this study was to determine whether a novel approach using a minimally invasive cell sampling device, the Cytosponge, coupled with immunohistochemical staining for the biomarker Trefoil Factor 3 (TFF3), could be used to identify patients who warrant endoscopy to diagnose BE. Methods and Findings A case–control study was performed across 11 UK hospitals between July 2011 and December 2013. In total, 1,110 individuals comprising 463 controls with dyspepsia and reflux symptoms and 647 BE cases swallowed a Cytosponge prior to endoscopy. The primary outcome measures were to evaluate the safety, acceptability, and accuracy of the Cytosponge-TFF3 test compared with endoscopy and biopsy. In all, 1,042 (93.9%) patients successfully swallowed the Cytosponge, and no serious adverse events were attributed to the device. The Cytosponge was rated favorably, using a visual analogue scale, compared with endoscopy (p < 0.001), and patients who were not sedated for endoscopy were more likely to rate the Cytosponge higher than endoscopy (Mann-Whitney test, p < 0.001). The overall sensitivity of the test was 79.9% (95% CI 76.4%–83.0%), increasing to 87.2% (95% CI 83.0%–90.6%) for patients with ≥3 cm of circumferential BE, known to confer a higher cancer risk. The sensitivity increased to 89.7% (95% CI 82.3%–94.8%) in 107 patients who swallowed the device twice during the study course. There was no loss of sensitivity in patients with dysplasia. The specificity for diagnosing BE was 92.4% (95% CI 89.5%–94.7%). The case–control design of the study means that the results are not generalizable to a primary care population. Another limitation is that the acceptability data were limited to a single measure. Conclusions The

  6. Population-based, Case-Control-Family Design to Investigate Genetic and Environmental Influences on Melanoma Risk

    PubMed Central

    Cust, Anne E.; Schmid, Helen; Maskiell, Judith A.; Jetann, Jodie; Ferguson, Megan; Holland, Elizabeth A.; Agha-Hamilton, Chantelle; Jenkins, Mark A.; Kelly, John; Kefford, Richard F.; Giles, Graham G.; Armstrong, Bruce K.; Aitken, Joanne F.; Hopper, John L.; Mann, Graham J.

    2009-01-01

    Discovering and understanding genetic risk factors for melanoma and their interactions with phenotype, sun exposure, and other risk factors could lead to new strategies for melanoma control. This paper describes the Australian Melanoma Family Study, which uses a multicenter, population-based, case-control-family design. From 2001 to 2005, the authors recruited 1,164 probands including 629 cases with histopathologically confirmed, first-primary cutaneous melanoma diagnosed before age 40 years, 240 population-based controls frequency matched for age, and 295 spouse/friend controls. Information on lifetime sun exposure, phenotype, and residence history was collected for probands and nearly 4,000 living relatives. More than 3,000 subjects donated a blood sample. Proxy-reported information was collected for childhood sun exposure and deceased relatives. Important features of this study include the population-based, family-based design; a focus on early onset disease; probands from 3 major cities differing substantially in solar ultraviolet exposure and melanoma incidence; a population at high risk because of high ultraviolet exposure and susceptible pigmentation phenotypes; population-based, spouse/friend, and sibling controls; systematic recruitment of relatives of case and control probands; self and parent reports of childhood sun exposure; and objective clinical skin examinations. The authors discuss methodological and analytical issues related to the study design and conduct, as well as the potentially novel insights the study can deliver. PMID:19887461

  7. 77 FR 9665 - Submission for OMB Emergency Review; Comment Request: A Multi-Center International Hospital-Based...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-17

    ... Multi- Center International Hospital-Based Case-Control Study of Lymphoma in Asia (AsiaLymph) (NCI... currently valid OMB control number. Proposed Collection: Title: A Multi-Center International Hospital- Based... viral infections, ultraviolet radiation exposure, medical conditions, and other lifestyle factors...

  8. Serotonin transporter 5HTTLPR polymorphism and affective disorders: no evidence of association in a large European multicenter study.

    PubMed

    Mendlewicz, Julien; Massat, Isabelle; Souery, Daniel; Del-Favero, Jurgen; Oruc, Lilijana; Nöthen, Markus M; Blackwood, Douglas; Muir, Walter; Battersby, Sharon; Lerer, Beny; Segman, Ronen H; Kaneva, Radka; Serretti, Alessandro; Lilli, Roberta; Lorenzi, Christian; Jakovljevic, Miro; Ivezic, Sladana; Rietschel, Marcella; Milanova, Vihra; Van Broeckhoven, Christine

    2004-05-01

    The available data from preclinical and pharmacological studies on the role of the serotonin transporter (5-HTT) support the hypothesis that a dysfunction in brain serotonergic system activity contributes to the vulnerability to affective disorders (AD). 5-HTT is the major site of serotonin reuptake into the presynaptic neuron, and it has been shown that the polymorphic repeat polymorphism in the 5-HTT promotor region (5-HTTLPR) may affect gene-transcription activity. 5-HTT maps to chromosome 17 at position 17q11.17-q12, and the 5-HTTLPR polymorphisms have been extensively investigated in AD with conflicting results. The present study tested the genetic contribution of the 5-HTTLPR polymorphism in a large European multicenter case-control sample, including 539 unipolar (UPAD), 572 bipolar patients (BPAD), and 821 controls (C). Our European collaboration has led to efforts to optimize a methodology that attenuates some of the major limitations of the case-control association approach. No association was found with primary psychiatric diagnosis (UPAD and BPAD) and with phenotypic traits (family history of AD, suicidal attempt, and presence of psychotic features). Our negative findings are not attributable to the lack of statistical power, and may contribute to clarify the role of 5-HTTLPR polymorphism in AD.

  9. Occupational Risk Factors for COPD: A Case-Control Study

    PubMed Central

    Drame, Moustapha; Lebargy, Francois; Deschamps, Frédéric

    2016-01-01

    Objectives The aim of this research was to examine the occupational risk factors for Chronic Obstructive Pulmonary Diseases (COPD) in a range of occupations. Methods Eleven occupations involving different types of exposure were observed in this multicenter case-control study. Controls and cases were matched for sex, age and smoking. Multiple logistic regression analyses were used to estimate odds ratios (ORs). Results A total of 1,519 participants were initially recruited between September 2004 and September 2012. After matching, 547 pairs were obtained. The mean age was 56.3 +/- 10.4 years. Smelter workers were the only ones with an increased risk of COPD in this study (OR = 7.6, p < 0.0001, 95% CI [4.5, 12.9]). Physical activity was protective (OR = 0.7), while living in the city was a risk (OR = 1.6). The main used metals were cast iron, aluminum and alloys. Molds and cores were mainly made from sand and synthetic resins. Machine maintenance (65.2%), molding (49.6%), finishing (41.1%) and casting (41.0%) were the most common activities. Almost all workers (95.1%) cleaned the floors and machines with a brush or compressed air. Conclusions This study demonstrates the importance of occupational factors in the genesis of COPD, especially among smelter workers. As with the fight against smoking-related disease, the removal or substitution of recognized hazardous agents is the best way of preventing the onset of COPD. This is why it is essential to continue research on its occupational risk factors. PMID:27487078

  10. Occupational risk factors for small bowel carcinoid tumor: a European population-based case-control study.

    PubMed

    Kaerlev, Linda; Teglbjaerg, Peter Stubbe; Sabroe, Svend; Kolstad, Henrik A; Ahrens, Wolfgang; Eriksson, Mikael; Guénel, Pascal; Hardell, Lennart; Cyr, Diane; Ballard, Terri; Zambon, Paola; Morales Suárez-Varela, María M; Stang, Andreas; Olsen, Jorn

    2002-06-01

    Small bowel carcinoid tumor (SBC) is a rare disease of unknown etiology but with an age-, sex-, and place-specific occurrence that may indicate an occupational origin. A European multicenter population-based case-control study was conducted from 1995 through 1997. Incident SBC cases between 35 and 69 years of age (n = 101) were identified, together with 3335 controls sampled from the catchment area of the cases. Histological review performed by a reference pathologist left 99 cases for study; 84 cases and 2070 population controls were interviewed. The industries most closely associated (a twofold or more odds ratio [OR]) with SBC, taking into account a 10-year time lag after exposure were, among women, employment in wholesale industry of food and beverages (OR, 8.2; 95% confidence interval [CI], 1.9 to 34.9]) and among men, manufacture of motor vehicle bodies (OR, 5.2; 95% CI, 1.2 to 22.4), footwear (OR, 3.9; 95% CI, 0.9 to 16.1), and metal structures (OR, 3.3; 95% CI, 1.0 to 10.4). The identified high-risk occupations with an OR above 2 were shoemakers, structural metal preparers, construction painters and other construction workers, bookkeepers, machine fitters, and welders (men). The OR for regular occupational use of organic solvents for at least half a year was 2.0 (95% CI, 1.0 to 4.2). Exposure to rust-preventive paint containing lead was suggested as another potential occupational exposure (OR, 9.1; 95% CI, 0.8 to 107). This explorative study suggests an association between certain occupational exposures and SBC, but some of these associations could be attributable to chance. All findings should be regarded as tentative.

  11. Mixed Model with Correction for Case-Control Ascertainment Increases Association Power

    PubMed Central

    Hayeck, Tristan J.; Zaitlen, Noah A.; Loh, Po-Ru; Vilhjalmsson, Bjarni; Pollack, Samuela; Gusev, Alexander; Yang, Jian; Chen, Guo-Bo; Goddard, Michael E.; Visscher, Peter M.; Patterson, Nick; Price, Alkes L.

    2015-01-01

    We introduce a liability-threshold mixed linear model (LTMLM) association statistic for case-control studies and show that it has a well-controlled false-positive rate and more power than existing mixed-model methods for diseases with low prevalence. Existing mixed-model methods suffer a loss in power under case-control ascertainment, but no solution has been proposed. Here, we solve this problem by using a χ2 score statistic computed from posterior mean liabilities (PMLs) under the liability-threshold model. Each individual’s PML is conditional not only on that individual’s case-control status but also on every individual’s case-control status and the genetic relationship matrix (GRM) obtained from the data. The PMLs are estimated with a multivariate Gibbs sampler; the liability-scale phenotypic covariance matrix is based on the GRM, and a heritability parameter is estimated via Haseman-Elston regression on case-control phenotypes and then transformed to the liability scale. In simulations of unrelated individuals, the LTMLM statistic was correctly calibrated and achieved higher power than existing mixed-model methods for diseases with low prevalence, and the magnitude of the improvement depended on sample size and severity of case-control ascertainment. In a Wellcome Trust Case Control Consortium 2 multiple sclerosis dataset with >10,000 samples, LTMLM was correctly calibrated and attained a 4.3% improvement (p = 0.005) in χ2 statistics over existing mixed-model methods at 75 known associated SNPs, consistent with simulations. Larger increases in power are expected at larger sample sizes. In conclusion, case-control studies of diseases with low prevalence can achieve power higher than that in existing mixed-model methods. PMID:25892111

  12. Informed Conditioning on Clinical Covariates Increases Power in Case-Control Association Studies

    PubMed Central

    Zaitlen, Noah; Lindström, Sara; Pasaniuc, Bogdan; Cornelis, Marilyn; Genovese, Giulio; Pollack, Samuela; Barton, Anne; Bickeböller, Heike; Bowden, Donald W.; Eyre, Steve; Freedman, Barry I.; Friedman, David J.; Field, John K.; Groop, Leif; Haugen, Aage; Heinrich, Joachim; Henderson, Brian E.; Hicks, Pamela J.; Hocking, Lynne J.; Kolonel, Laurence N.; Landi, Maria Teresa; Langefeld, Carl D.; Le Marchand, Loic; Meister, Michael; Morgan, Ann W.; Raji, Olaide Y.; Risch, Angela; Rosenberger, Albert; Scherf, David; Steer, Sophia; Walshaw, Martin; Waters, Kevin M.; Wilson, Anthony G.; Wordsworth, Paul; Zienolddiny, Shanbeh; Tchetgen, Eric Tchetgen; Haiman, Christopher; Hunter, David J.; Plenge, Robert M.; Worthington, Jane; Christiani, David C.; Schaumberg, Debra A.; Chasman, Daniel I.; Altshuler, David; Voight, Benjamin; Kraft, Peter; Patterson, Nick; Price, Alkes L.

    2012-01-01

    Genetic case-control association studies often include data on clinical covariates, such as body mass index (BMI), smoking status, or age, that may modify the underlying genetic risk of case or control samples. For example, in type 2 diabetes, odds ratios for established variants estimated from low–BMI cases are larger than those estimated from high–BMI cases. An unanswered question is how to use this information to maximize statistical power in case-control studies that ascertain individuals on the basis of phenotype (case-control ascertainment) or phenotype and clinical covariates (case-control-covariate ascertainment). While current approaches improve power in studies with random ascertainment, they often lose power under case-control ascertainment and fail to capture available power increases under case-control-covariate ascertainment. We show that an informed conditioning approach, based on the liability threshold model with parameters informed by external epidemiological information, fully accounts for disease prevalence and non-random ascertainment of phenotype as well as covariates and provides a substantial increase in power while maintaining a properly controlled false-positive rate. Our method outperforms standard case-control association tests with or without covariates, tests of gene x covariate interaction, and previously proposed tests for dealing with covariates in ascertained data, with especially large improvements in the case of case-control-covariate ascertainment. We investigate empirical case-control studies of type 2 diabetes, prostate cancer, lung cancer, breast cancer, rheumatoid arthritis, age-related macular degeneration, and end-stage kidney disease over a total of 89,726 samples. In these datasets, informed conditioning outperforms logistic regression for 115 of the 157 known associated variants investigated (P-value = 1×10−9). The improvement varied across diseases with a 16% median increase in χ2 test statistics and a

  13. 77 FR 11136 - Proposed Collection; Comment Request; a Multi-Center International Hospital-Based Case-Control...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-24

    ... National Institutes of Health (NIH) will publish periodic summaries of proposed projects to be submitted to... enrolled at treating hospitals. The annual reporting burden is estimated at 5,302 hours (see Table...

  14. Staphylococcus aureus in Acne Pathogenesis: A Case-Control Study

    PubMed Central

    Khorvash, Farzin; Abdi, Fatemeh; Kashani, Hessam H.; Naeini, Farahnaz Fatemi; Narimani, Tahmineh

    2012-01-01

    Background: There is considerable evidence which suggests a possible pathogenetic role for Staphylococcus aureus (S. aureus) in acne vulgaris. Aim: The study was to determine S. aureus colonization and antibiotic susceptibility patterns in patients with acne and of healthy people. Materials and Methods: In the case-control study, a total of 324 people were screened for nasal carriage of S. aureus: 166 acne patients and 158 healthy persons. One control subject was individually matched to one case. Nasal swabs from anterior nares of individuals were cultured and identified as S. aureus. Antibiotic sensitivity was performed with recognized laboratory techniques. Results: S. aureus was detected in 21.7% of the subjects in acne, and in 26.6% of control groups. There was no statistical difference in colonization rates between two groups (P=0.3). In patient group, most of S. aureus isolates were resistant to doxicycline and tetracycline (P=0.001), and were more sensitive to rifampicin compared to other drugs. In control samples, the isolated demonstrated higher resistance to cotrimoxazole compared to patient samples (P=0.0001). There was no difference between groups regarding resistance to rifampicin, vancomycin, methicillin, and oxacillin. Conclusion: It is still unclear whether S. aureus is actually a causal agent in the pathogenesis of acne. Based on microbiological data of both healthy and acne-affected persons, we propose that contribution of S. aureus in acne pathogenesis is controversial. PMID:23181229

  15. Robust analysis of secondary phenotypes in case-control genetic association studies.

    PubMed

    Xing, Chuanhua; M McCarthy, Janice; Dupuis, Josée; Adrienne Cupples, L; B Meigs, James; Lin, Xihong; S Allen, Andrew

    2016-10-15

    The case-control study is a common design for assessing the association between genetic exposures and a disease phenotype. Though association with a given (case-control) phenotype is always of primary interest, there is often considerable interest in assessing relationships between genetic exposures and other (secondary) phenotypes. However, the case-control sample represents a biased sample from the general population. As a result, if this sampling framework is not correctly taken into account, analyses estimating the effect of exposures on secondary phenotypes can be biased leading to incorrect inference. In this paper, we address this problem and propose a general approach for estimating and testing the population effect of a genetic variant on a secondary phenotype. Our approach is based on inverse probability weighted estimating equations, where the weights depend on genotype and the secondary phenotype. We show that, though slightly less efficient than a full likelihood-based analysis when the likelihood is correctly specified, it is substantially more robust to model misspecification, and can out-perform likelihood-based analysis, both in terms of validity and power, when the model is misspecified. We illustrate our approach with an application to a case-control study extracted from the Framingham Heart Study. Copyright © 2016 John Wiley & Sons, Ltd.

  16. The association of beta-2 adrenoceptor genotype with short-cervix mediated preterm birth: a case-control study

    PubMed Central

    Miller, Russell; Smiley, Richard; Thom, Elizabeth A.; Grobman, William A.; Iams, Jay D.; Mercer, Brian M.; Saade, George; Tita, Alan T.; Reddy, Uma M.; Rouse, Dwight J.; Sorokin, Yoram; Blackwell, Sean C.; Esplin, M. Sean; Tolosa, Jorge E.; Caritis, Steve N.

    2014-01-01

    OBJECTIVE To determine if β2-adrenoceptor (β2AR) genotype is associated with shortening of the cervix or with preterm birth (PTB) risk among subjects with a short cervix in the second trimester. DESIGN A case-control ancillary study to a multicenter randomized controlled trial. SETTING 14 participating centers of the Maternal-Fetal Medicine Units Network of the Eunice Kennedy Shriver National Institute of Child Health and Human Development. POPULATION 439 subjects, including 315 with short cervix and 124 with normal cervical length. METHODS Nulliparous women with cervical length <30mm upon 16–22 week transvaginal sonogram and controls frequency-matched for race/ethnicity with cervical lengths ≥40mm were studied. β2AR genotype was determined at positions encoding for amino acid residues 16 and 27. MAIN OUTCOME MEASURES Genotype distributions were compared between case and control groups. Within the short cervix group, pregnancy outcomes were compared by genotype, with a primary outcome of PTB <37 weeks. RESULTS Genotype data were available at position 16 for 433 subjects and position 27 for 437. Using a recessive model testing for association between short cervix and genotype, and adjusted for ethnicity, there was no statistical difference between cases and controls for Arg16 homozygosity (OR 0.7, 95% CI 0.4–1.3) or Gln27 homozygosity (OR 0.9, 95% CI 0.3–2.7). Among cases, Arg16 homozygosity was not associated with protection from PTB or spontaneous PTB. Gln27 homozygosity was not associated with PTB risk, although sample size was limited. CONCLUSIONS β2AR genotype does not seem to be associated with short cervical length or with PTB following the second-trimester identification of a short cervix. Influences on PTB associated with β2AR genotype do not appear to involve a short cervix pathway. TWEETABLE ABSTRACT β2AR gene variation was not associated with short cervix or with PTB risk following a short cervix diagnosis. PMID:25600430

  17. Relationship between Urinary N-Desmethyl-Acetamiprid and Typical Symptoms including Neurological Findings: A Prevalence Case-Control Study.

    PubMed

    Marfo, Jemima Tiwaa; Fujioka, Kazutoshi; Ikenaka, Yoshinori; Nakayama, Shouta M M; Mizukawa, Hazuki; Aoyama, Yoshiko; Ishizuka, Mayumi; Taira, Kumiko

    2015-01-01

    Neonicotinoid insecticides are nicotinic acetylcholine receptor agonists used worldwide. Their environmental health effects including neurotoxicity are of concern. We previously determined a metabolite of acetamiprid, N-desmethyl-acetamiprid in the urine of a patient, who exhibited some typical symptoms including neurological findings. We sought to investigate the association between urinary N-desmethyl-acetamiprid and the symptoms by a prevalence case-control study. Spot urine samples were collected from 35 symptomatic patients of unknown origin and 50 non-symptomatic volunteers (non-symptomatic group, NSG, 4-87 year-old). Patients with recent memory loss, finger tremor, and more than five of six symptoms (headache, general fatigue, palpitation/chest pain, abdominal pain, muscle pain/weakness/spasm, and cough) were in the typical symptomatic group (TSG, n = 19, 5-69 year-old); the rest were in the atypical symptomatic group (ASG, n = 16, 5-78 year-old). N-desmethyl-acetamiprid and six neonicotinoids in the urine were quantified by liquid chromatography-tandem mass spectrometry. The detection of N-desmethyl-acetamiprid was the most frequent and highest in TSG (47.4%, 6.0 ppb (frequency, maximum)), followed by in ASG (12.5%, 4.4 ppb) and in NSG (6.0%, 2.2 ppb), however acetamiprid was not detected. Thiamethoxam was detected in TSG (31.6%, 1.4 ppb), in ASG (6.3%, 1.9 ppb), but not in NSG. Nitenpyram was detected in TSG (10.5%, 1.2 ppb), in ASG (6.3%, not quantified) and in NSG (2.0%, not quantified). Clothianidin was only detected in ASG (6.3%, not quantified), and in NSG (2.0%, 1.6 ppb). Thiacloprid was detected in ASG (6.3%, 0.1 ppb). The cases in TSG with detection of N-desmethyl-acetamiprid and thiamethoxam were aged 5 to 62 years and 13 to 62 years, respectively. Detection of N-desmethyl-acetamiprid was associated with increased prevalence of the symptoms (odds ratio: 14, 95% confidence interval: 3.5-57). Urinary N-desmethyl-acetamiprid can be used as a

  18. Relationship between Urinary N-Desmethyl-Acetamiprid and Typical Symptoms including Neurological Findings: A Prevalence Case-Control Study

    PubMed Central

    Ikenaka, Yoshinori; Nakayama, Shouta M. M.; Mizukawa, Hazuki; Aoyama, Yoshiko; Ishizuka, Mayumi; Taira, Kumiko

    2015-01-01

    Neonicotinoid insecticides are nicotinic acetylcholine receptor agonists used worldwide. Their environmental health effects including neurotoxicity are of concern. We previously determined a metabolite of acetamiprid, N-desmethyl-acetamiprid in the urine of a patient, who exhibited some typical symptoms including neurological findings. We sought to investigate the association between urinary N-desmethyl-acetamiprid and the symptoms by a prevalence case-control study. Spot urine samples were collected from 35 symptomatic patients of unknown origin and 50 non-symptomatic volunteers (non-symptomatic group, NSG, 4–87 year-old). Patients with recent memory loss, finger tremor, and more than five of six symptoms (headache, general fatigue, palpitation/chest pain, abdominal pain, muscle pain/weakness/spasm, and cough) were in the typical symptomatic group (TSG, n = 19, 5–69 year-old); the rest were in the atypical symptomatic group (ASG, n = 16, 5–78 year-old). N-desmethyl-acetamiprid and six neonicotinoids in the urine were quantified by liquid chromatography-tandem mass spectrometry. The detection of N-desmethyl-acetamiprid was the most frequent and highest in TSG (47.4%, 6.0 ppb (frequency, maximum)), followed by in ASG (12.5%, 4.4 ppb) and in NSG (6.0%, 2.2 ppb), however acetamiprid was not detected. Thiamethoxam was detected in TSG (31.6%, 1.4 ppb), in ASG (6.3%, 1.9 ppb), but not in NSG. Nitenpyram was detected in TSG (10.5%, 1.2 ppb), in ASG (6.3%, not quantified) and in NSG (2.0%, not quantified). Clothianidin was only detected in ASG (6.3%, not quantified), and in NSG (2.0%, 1.6 ppb). Thiacloprid was detected in ASG (6.3%, 0.1 ppb). The cases in TSG with detection of N-desmethyl-acetamiprid and thiamethoxam were aged 5 to 62 years and 13 to 62 years, respectively. Detection of N-desmethyl-acetamiprid was associated with increased prevalence of the symptoms (odds ratio: 14, 95% confidence interval: 3.5–57). Urinary N-desmethyl-acetamiprid can be used as a

  19. Multicenter Study of Hand Carriage of Potential Pathogens by Neonatal ICU Healthcare Personnel

    PubMed Central

    Ferng, Yu-hui; Clock, Sarah A.; Wong-Mcloughlin, Jennifer; DeLaMora, Patricia A.; Perlman, Jeffrey M.; Gray, Kelly S.; Paul, David A.; Prasad, Priya A.; Zaoutis, Theoklis E.; Alba, Luis R.; Whittier, Susan; Larson, Elaine L.; Saiman, Lisa

    2015-01-01

    A multicenter surveillance study was performed to determine the rates of hand carriage of potential pathogens among healthcare personnel in four neonatal intensive care units. Staphylococcus aureus, enterococci, and gram-negative bacilli were recovered from 8%, 3%, and 2% of 1000 hand culture samples, respectively. PMID:26336605

  20. Testing Goodness-of-Fit for the Proportional Hazards Model based on Nested Case-Control Data

    PubMed Central

    Lu, Wenbin; Liu, Mengling; Chen, Yi-Hau

    2014-01-01

    Summary Nested case-control sampling is a popular design for large epidemiological cohort studies due to its cost effectiveness. A number of methods have been developed for the estimation of the proportional hazards model with nested case-control data; however, the evaluation of modeling assumption is less attended. In this paper, we propose a class of goodness-of-fit test statistics for testing the proportional hazards assumption based on nested case-control data. The test statistics are constructed based on asymptotically mean-zero processes derived from Samuelsen’s maximum pseudo-likelihood estimation method. In addition, we develop an innovative resampling scheme to approximate the asymptotic distribution of the test statistics while accounting for the dependent sampling scheme of nested case-control design. Numerical studies are conducted to evaluate the performance of our proposed approach, and an application to the Wilms’ Tumor Study is given to illustrate the methodology. PMID:25298193

  1. The Global Enteric Multicenter Study (GEMS): Impetus, Rationale, and Genesis

    PubMed Central

    Levine, Myron M.; Kotloff, Karen L.; Nataro, James P.; Muhsen, Khitam

    2012-01-01

    Diarrheal disease remains one of the top 2 causes of young child mortality in the developing world. Whereas improvements in water/sanitation infrastructure and hygiene can diminish transmission of enteric pathogens, vaccines can also hasten the decline of diarrheal disease morbidity and mortality. From 1980 through approximately 2004, various case/control and small cohort studies were undertaken to address the etiology of pediatric diarrhea in developing countries. Many studies had methodological limitations and came to divergent conclusions, making it difficult to prioritize the relative importance of different pathogens. Consequently, in the first years of the millennium there was no consensus on what diarrheal disease vaccines should be developed or implemented; however, there was consensus on the need for a well-designed study to obtain information on the etiology and burden of more severe forms of diarrheal disease to guide global investment and implementation decisions. Accordingly, the Global Enteric Multicenter Study (GEMS) was designed to overcome drawbacks of earlier studies and determine the etiology and population-based burden of pediatric diarrheal disease. GEMS, which includes one of the largest case/control studies of an infectious disease syndrome ever undertaken (target approximately 12 600 analyzable cases and 12 600 controls), was rolled out in 4 sites in sub-Saharan Africa (Gambia, Kenya, Mali, Mozambique) and 3 in South Asia (Bangladesh, India, Pakistan), with each site linked to a population under demographic surveillance (total approximately 467 000 child years of observation among children <5 years of age). GEMS data will guide investment and help prioritize strategies to mitigate the morbidity and mortality of pediatric diarrheal disease. PMID:23169934

  2. Toxic substance exposure and multiple myeloma: a case-control study.

    PubMed

    Morris, P D; Koepsell, T D; Daling, J R; Taylor, J W; Lyon, J L; Swanson, G M; Child, M; Weiss, N S

    1986-06-01

    By means of a population-based, multicenter case-control investigation, certain toxic substances were evaluated as risk factors for multiple myeloma. Interviews were completed on 698 subjects with newly diagnosed multiple myeloma, and 1,683 controls were selected from the same geographic areas as those of the cases. Respondents were asked if they had ever been "highly" exposed" to one or more of a list of toxic substances or to other substances not on the list. With the aid of a toxicologist, responses were then categorized into 20 exposure groups. Those who reported past exposure to pesticides had an estimated relative risk of 2.6 for multiple myeloma [95% confidence interval (CI) = 1.5-4.6]. Subjects exposed to a variety of compounds commonly used by painters had an estimated relative risk of 1.6 (95% CI = 1.1-2.4). An increased risk also was found for those who were exposed to sources of carbon monoxide (relative risk = 1.8, 95% CI = 1.0-3.2). Associations of borderline statistical significance were found for metals and organically high polymers (plastics and elastomers). No statistically significant associations were seen for exposure to fertilizers; dyes and inks; alkalies; acids; other caustic substances; chemical asphyxiants; aliphatic, chlorinated, or aromatic hydrocarbons; aldehydes and ketones; ethers; esters; oils; dusts; or asbestos.

  3. Outdoor Air Pollution and Cardiovascular Diseases in Lebanon: A Case-Control Study

    PubMed Central

    Nasser, Zeina; Salameh, Pascale; Dakik, Habib; Elias, Elias; Abou Abbas, Linda; Levêque, Alain

    2015-01-01

    Outdoor air pollution is increasingly considered as a serious threat for cardiovascular diseases (CVD). The aim of this study is to investigate the association between outdoor pollutants and cardiovascular diseases among adults in Lebanon and to examine the possible moderator effect of cigarette smoking status on this association. A multicenter case-control study was conducted between October 2011 and October 2012. Cases were hospitalized patients diagnosed with CVD by a cardiologist while the control group subjects were free of any cardiac diseases. Information on sociodemographic characteristics, tobacco consumption, self-rated global health, pollution exposure, and other risk factors was collected using a questionnaire. The results of the logistic regression revealed that living near busy highway (OR 5.04, 95% CI (4.44–12.85), P < 0.001) and close to local diesel generator (OR 4.76, 95% CI (2.07–10.91), P < 0.001) was significantly associated with CVD. The association between the CVD and exposure to outside pollutants differed by cigarette smoking status. A clear difference was noted between nonsmokers and current smokers OR 4.6, 95% CI (1.10–19.25) and OR 10.11, 95% CI (7.33–20.23), respectively. Forthcoming studies are needed to clarify the potential link between outdoor air pollution and cardiovascular diseases in Lebanon. Public health interventions must be implemented to reduce air pollution and to improve air quality. PMID:25653681

  4. Analysis of Secondary Outcomes in Nested Case-Control Study Designs

    PubMed Central

    Kim, Ryung S.; Kaplan, Robert C.

    2014-01-01

    One of the main perceived advantages of using a case-cohort design compared to a nested case-control design in an epidemiologic study is the ability to evaluate with the same subcohort outcomes other than the primary outcome of interest. In this paper, we show that valid inferences about secondary outcomes can also be achieved in nested case-control studies by using the inclusion probability weighting method originally proposed by Samuelsen (1997) in combination with an approximate jackknife standard error that can be computed using existing software. Simulation studies demonstrate that when the sample size is sufficient, this approach yields valid type 1 error and coverage rates for the analysis of secondary outcomes in nested case-control designs. Interestingly, the statistical power of the nested case-control design was comparable to that of the case-cohort design when the primary and secondary outcomes were positively correlated. The proposed method is illustrated with data from a cohort in Cardiovascular Health Study to study the association of C-reactive protein levels and the incidence of congestive heart failure. PMID:24919979

  5. Case-control studies in clinical research: mechanism and prevention of selection bias.

    PubMed

    Morabia, A

    1997-01-01

    The mechanism by which selection bias occurs in case-control studies is explained to an audience of clinicians using a simple conceptual framework and a graphical presentation. A case-control study consists in comparing the frequency of exposure in a group of subjects having the studied disease (the cases) relative to another group free of that disease (the controls). Cases and controls can be thought of as arising from a hypothetical cohort study. Thus, enrolled cases are a fraction F1 of the exposed who developed the disease plus a fraction F3 of the unexposed who developed the disease during a given period. Similarly, enrolled controls are a fraction F2 of the exposed who did not develop disease plus a fraction F4 of the unexposed who did not develop the disease. A selection process is inherent to the design of case-control studies but it leads to selection bias only when the ratio of F1 x F4/F2 x F3 is not equal to unity. Examples demonstrate the implication of sampling fractions for designing and interpreting case-control studies performed in clinical settings.

  6. Multicenter comparative study of a new ELISA, PLATELIA RABIES II, for the detection and titration of anti-rabies glycoprotein antibodies and comparison with the rapid fluorescent focus inhibition test (RFFIT) on human samples from vaccinated and non-vaccinated people.

    PubMed

    Feyssaguet, M; Dacheux, L; Audry, L; Compoint, A; Morize, J L; Blanchard, I; Bourhy, H

    2007-03-01

    The envelope glycoprotein G of rabies virus induces the production of neutralising antibodies, which are important in protection against rabies. Therefore, titration of anti-envelope glycoprotein antibodies is a good indicator of the degree of immunity in people during anti-rabies treatment or after vaccination. According to the World Health Organization (WHO) guidelines, a booster vaccine dose should be given if the rabies antibody titre falls below 0.5 IU/ml. Titration of anti-rabies antibodies is also useful for plasma centers in the preparation and standardization of human anti-rabies gamma-globulins for therapeutic use and to a lesser extent for the diagnosis of rabies in human sera and cerebrospinal fluid (CSF). This paper presents a new enzyme-linked immunosorbent assay (ELISA), PLATELIA RABIES II, developed for rabies envelope glycoprotein antibody detection or titration and its comparison to the current reference method (RFFIT). The data collected during validation of the test in a multicenter study are analysed to give a sound overall knowledge of the capabilities of the PLATELIA RABIES II, for instance specificity, linearity, accuracy, precision, detection limit and quantitation limit. To this aim, human serum samples from a total of 1348 vaccinated or non-vaccinated people were tested in parallel using the new ELISA and the RFFIT for the presence of anti-rabies antibodies. Data generated indicate a linear relationship across the range of titration between the two methods. The sensitivity reaches 98.6% and the specificity 99.4%. This study indicates that this new ELISA test is as sensitive and specific as the current standardized reference method. The method is simple, safe, rapid and can be considered as a useful alternative to the neutralisation test.

  7. Multicenter Guidelines | Division of Cancer Prevention

    Cancer.gov

    A Lead Organization conducting multi-institutional studies in the consortium has specific responsibilities in order to comply with the DCP Multicenter Guidelines. The Lead Organization is responsible for the following at all Participating Organizations as well as the Lead Organization: |

  8. Signal generation and clarification: use of case-control data.

    PubMed

    Kaufman, D W; Rosenberg, L; Mitchell, A A

    2001-05-01

    Case-control surveillance systems are useful for 'signal' generation, i.e., signaling potential previously unidentified adverse effects of drugs. Two systems currently in operation, the Slone Epidemiology Unit's Case-Control Surveillance and the Birth Defects Study, have monitored drug effects since 1976. With extensive information on the diagnoses and covariates, the systems have the capacity to carry out in-depth analyses in which the outcome measure is more specifically defined and in which confounding is controlled, thus reducing the possibility of false alarms.

  9. Regular aspirin use and nasopharyngeal cancer risk: A case-control study in Italy.

    PubMed

    Di Maso, Matteo; Bosetti, Cristina; La Vecchia, Carlo; Garavello, Werner; Montella, Maurizio; Libra, Massimo; Serraino, Diego; Polesel, Jerry

    2015-08-01

    Regular aspirin use has been associated to decreased risk of several cancers, but evidence on nasopharyngeal carcinoma is scanty. We conducted a hospital-based case-control study in Italy, enrolling 198 Caucasian patients with nasopharyngeal carcinoma. Controls were 592 cancer-free Caucasian patients admitted to the same catchment areas as cases; controls were frequency matched according to sex, age, and area of residence. Regular aspirin use was defined as taking at least one aspirin a week for at least 6 months. Three cases (1.5%) and 27 controls (4.5%) reported regular aspirin use (odds ratio=0.24; 95% CI: 0.07-0.87). The median duration of consumption was 15 months among cases and 60 months among controls. Although study findings should be considered with caution due to limited sample size, they provide further evidence on the protective effect of aspirin use in head and neck cancers.

  10. Fibre intake and renal cell carcinoma: a case-control study from Italy.

    PubMed

    Galeone, Carlotta; Pelucchi, Claudio; Talamini, Renato; Negri, Eva; Montella, Maurizio; Ramazzotti, Valerio; Zucchetto, Antonella; Dal Maso, Luigino; Franceschi, Silvia; La Vecchia, Carlo

    2007-10-15

    Only 2 previous studies, conducted in Australia, United States and northern Europe, considered the role of dietary fibre intake on renal cell carcinoma (RCC) risk, and both showed a modest, inverse association. Therefore, we investigated in depth the topic of fibres and RCC, using data from a multicenter case-control study conducted in Italy from 1992 to 2004, including 767 cases with incident, histologically confirmed RCC and 1,534 controls admitted to the same network of hospitals as cases with acute nonmalignant conditions. Multivariate odds ratios (OR) and 95% confidence intervals (CI) were obtained after allowance for major identified confounding factors, including total energy intake. The continuous OR for an increase in intake equal to the difference between the 80th and the 20th percentile were 0.94 (95% CI: 0.82-1.08) for total dietary fibre, 0.98 (95% CI: 0.85-1.13) for soluble noncellulose polysaccharides, 0.92 (95% CI: 0.80-1.05) for total insoluble fibre, 0.90 (95% CI: 0.78-1.04) for cellulose, 0.95 (95% CI: 0.84-1.06) for insoluble noncellulose polysaccharides and 1.06 (95% CI: 0.93-1.21) for lignin. With reference to the sources of fibre, we found an inverse association with vegetable fibre (OR = 0.84, 95% CI: 0.73-0.97), but no association with fruit (OR = 0.98, 95% CI: 0.86-1.12) and grain fibre (OR = 1.05, 95% CI: 0.95-1.15). The inverse association with vegetable fibre may reflect a real favorable effect, or be an indicator of a beneficial role of a diet rich in vegetable on RCC risk. PMID:17582601

  11. Risk factors in patients with oral pemphigus vulgaris: a case-control study.

    PubMed

    Bakhshi, Mahin; Manifar, Soheila; Azizi, Nemat; Asayesh, Hamid; Mansouri, Parvin; Nasiri, Soheila; Hashemi, Zeynab; Mehdipour, Aida

    2016-01-01

    Pemphigus vulgaris (PV) is considered a chronic disease with a potentially fatal outcome. Studies have suggested that environmental factors and personal habits play an important role in the pathogenesis of PV, but more studies are required to elaborate their connection to the disease. The goal of this multicenter case-control study was to determine some of the environmental factors related to PV. Cases (n = 99) were patients with PV, and controls (n = 198) were individuals who did not have PV. Data about demographics, history, clinical findings, occupational exposures to pesticides, smoking status, number of births (parity), herpes simplex virus (HSV) infection, and fast food consumption were collected using a structured questionnaire. Chi-square and logistic regression analyses were used for data analysis. Univariate logistic regression analysis indicated that the statistically significant factors related to PV were infection with HSV in recent weeks (odds ratio [OR], 3.35; 95% confidence interval [CI], 1.75-6.43), parity (OR, 0.50; 95% CI, 0.39-0.63), and lack of occupational exposure to pesticides (OR, 0.36; 95% CI, 0.21-0.60). Multivariate analysis revealed that significant factors were cessation of smoking (adjusted odds ratio [AOR], 4.36; 95% CI, 1.50-12.66), HSV infection (AOR, 2.91; 95% CI, 1.47-5.75), and lack of occupational exposure to pesticides (AOR, 0.35; 95% CI, 0.20-0.63). The findings indicated that cessation of smoking and HSV infection in recent weeks are risk factors for PV, while lack of occupational exposure to pesticides and increasing parity (a greater number of births) are protective factors against PV. PMID:27148665

  12. Adiponectin and noncardiovascular death: a nested case-control study.

    PubMed

    Matsumoto, Masatoshi; Ishikawa, Shizukiyo; Kajii, Eiji

    2008-06-01

    This study is to evaluate the associations between adiponectin level and noncardiovascular death and to test a hypothesis that adiponectin level reflects the degree of systemic wasting that precedes death. A nested case-control study was conducted involving 5243 subjects, drawn from 12490 subjects of the Jichi Medical School Cohort Study, whose blood samples had been drawn between 1992 and 1995. Over an average of 10.8 years of follow-up, 103 cases with noncardiovascular death and 565 controls without history/event/death of any cardiovascular disease were identified. Odds ratios (ORs) were estimated relative to the lowest quintile of adiponectin level. The risks for noncardiovascular death of the second lowest quintile and the highest quintile of adiponectin level were significantly higher than that of the lowest quintile when adjusted for age and sex (model 1) (OR, 2.38 [95% confidence interval (CI), 1.12-5.06] and 2.16 [1.01-4.80]). All the statistical significances disappeared when adjusted further for body mass index and C-reactive protein level (model 2). When excluding cases with cancer death, the odds for death in the highest 2 quintiles were significantly higher than those in the lowest quintile in model 1 (OR, 2.80 [95% CI, 1.04-7.59] and 3.74 [1.38-10.18]). The significant difference between the highest vs the lowest quintile remained significant in model 2 and even after adjusting further for smoking, diabetes, and total cholesterol level (model 3) (OR, 3.28 [95% CI, 1.02-10.51] and 3.98 [1.21-13.13]). Adiponectin levels had linear associations with the risks of noncardiovascular noncancer death in models 1, 2, and 3 (OR per 1 SD increase in log-adiponectin, 1.72 [95% CI, 1.23-2.40], 1.89 [1.23-2.91], and 2.01 [1.29-3.15]). Adiponectin is an independent indicator of noncardiovascular mortality that may relate with systemic wasting.

  13. A re-evaluation of a case-control model with contaminated controls for resource selection studies.

    PubMed

    Rota, Christopher T; Millspaugh, Joshua J; Kesler, Dylan C; Lehman, Chad P; Rumble, Mark A; Jachowski, Catherine M B

    2013-11-01

    1. A common sampling design in resource selection studies involves measuring resource attributes at sample units used by an animal and at sample units considered available for use. Few models can estimate the absolute probability of using a sample unit from such data, but such approaches are generally preferred over statistical methods that estimate a relative probability of use. 2. The case-control model that allows for contaminated controls, proposed by Lancaster & Imbens (1996) and Lele (2009), can estimate the absolute probability of using a sample unit from use-availability data. However, numerous misconceptions have likely prevented the widespread application of this model to resource selection studies. We address common misconceptions regarding the case-control model with contaminated controls and demonstrate its ability to estimate the absolute probability of use, prevalence and parameters associated with categorical covariates from use-availability data. 3. We fit the case-control model with contaminated controls to simulated data with varying prevalence (defined as the average probability of use across all sample units) and sample sizes (n1 = 500 used and na = 500 available samples; n1 = 1000 used and na = 1000 available samples). We then applied this model to estimate the probability Ozark hellbenders (Cryptobranchus alleganiensis bishopi) would use a location within a stream as a function of covariates. 4. The case-control model with contaminated controls provided unbiased estimates of all parameters at N = 2000 sample size simulation scenarios, particularly at low prevalence. However, this model produced increasingly variable maximum likelihood estimates of parameters as prevalence increased, particularly at N = 1000 sample size scenarios. We thus recommend at least 500-1000 used samples when fitting the case-control model with contaminated controls to use-availability data. Our application to hellbender data revealed selection for locations with

  14. Smoking during Pregnancy and Attention-Deficit/Hyperactivity Disorder, Predominantly Inattentive Type: A Case-Control Study

    ERIC Educational Resources Information Center

    Schmitz, Marcelo; Denardin, Daniel; Silva, Tatiana Laufer; Pianca, Thiago; Hutz, Mara Helena; Faraone, Stephen; Rohde, Luis Augusto

    2006-01-01

    Objective: Few previous studies assessed specifically attention-deficit/hyperactivity disorder, predominantly inattentive subtype (ADHD-I) in nonreferred samples. This study investigated the association between ADHD-I and prenatal exposure to nicotine. Method: In a case-control study performed between September 2002 and April 2005, we assessed a…

  15. Methodology Series Module 2: Case-control Studies

    PubMed Central

    Setia, Maninder Singh

    2016-01-01

    Case-Control study design is a type of observational study. In this design, participants are selected for the study based on their outcome status. Thus, some participants have the outcome of interest (referred to as cases), whereas others do not have the outcome of interest (referred to as controls). The investigator then assesses the exposure in both these groups. The investigator should define the cases as specifically as possible. Sometimes, definition of a disease may be based on multiple criteria; thus, all these points should be explicitly stated in case definition. An important aspect of selecting a control is that they should be from the same ‘study base’ as that of the cases. We can select controls from a variety of groups. Some of them are: General population; relatives or friends; and hospital patients. Matching is often used in case-control control studies to ensure that the cases and controls are similar in certain characteristics, and it is a useful technique to increase the efficiency of the study. Case-Control studies can usually be conducted relatively faster and are inexpensive – particularly when compared with cohort studies (prospective). It is useful to study rare outcomes and outcomes with long latent periods. This design is not very useful to study rare exposures. Furthermore, they may also be prone to certain biases – selection bias and recall bias. PMID:27057012

  16. Comparison of nested case-control and survival analysis methodologies for analysis of time-dependent exposure

    PubMed Central

    Essebag, Vidal; Platt, Robert W; Abrahamowicz, Michal; Pilote, Louise

    2005-01-01

    Background Epidemiological studies of exposures that vary with time require an additional level of methodological complexity to account for the time-dependence of exposure. This study compares a nested case-control approach for the study of time-dependent exposure with cohort analysis using Cox regression including time-dependent covariates. Methods A cohort of 1340 subjects with four fixed and seven time-dependent covariates was used for this study. Nested case-control analyses were repeated 100 times for each of 4, 8, 16, 32, and 64 controls per case, and point estimates were compared to those obtained using Cox regression on the full cohort. Computational efficiencies were evaluated by comparing central processing unit times required for analysis of the cohort at sizes 1, 2, 4, 8, 16, and 32 times its initial size. Results Nested case-control analyses yielded results that were similar to results of Cox regression on the full cohort. Cox regression was found to be 125 times slower than the nested case-control approach (using four controls per case). Conclusions The nested case-control approach is a useful alternative for cohort analysis when studying time-dependent exposures. Its superior computational efficiency may be particularly useful when studying rare outcomes in databases, where the ability to analyze larger sample sizes can improve the power of the study. PMID:15670334

  17. Non-parametric Evaluation of Biomarker Accuracy under Nested Case-control Studies

    PubMed Central

    Cai, Tianxi; Zheng, Yingye

    2012-01-01

    Summary To evaluate the clinical utility of new risk markers, a crucial step is to measure their predictive accuracy with prospective studies. However, it is often infeasible to obtain marker values for all study participants. The nested case-control (NCC) design is a useful cost-effective strategy for such settings. Under the NCC design, markers are only ascertained for cases and a fraction of controls sampled randomly from the risk sets. The outcome dependent sampling generates a complex data structure and therefore a challenge for analysis. Existing methods for analyzing NCC studies focus primarily on association measures. Here, we propose a class of non-parametric estimators for commonly used accuracy measures. We derived asymptotic expansions for accuracy estimators based on both finite population and Bernoulli sampling and established asymptotic equivalence between the two. Simulation results suggest that the proposed procedures perform well in finite samples. The new procedures were illustrated with data from the Framingham Offspring study. PMID:22844169

  18. A case-control study of the effect of environmental sanitation on diarrhoea morbidity in Malawi.

    PubMed Central

    Young, B; Briscoe, J

    1988-01-01

    A case-control design has been applied in the evaluation of improved environmental sanitation on diarrhoeal diseases in rural Malawi. The study demonstrates the feasibility of using such an approach to evaluate two levels of water supply and sanitation service quickly and at moderate cost. Sample sizes would need to be increased substantially to evaluate multiple levels of service or to investigate interactions between water supply and sanitation. The results indicate that children living in families who use good quality water supplies and latrines experience 20% less diarrhoea as reported to the health clinics during the warm, rainy season. PMID:3418292

  19. A case-control study of the effect of environmental sanitation on diarrhoea morbidity in Malawi.

    PubMed

    Young, B; Briscoe, J

    1988-03-01

    A case-control design has been applied in the evaluation of improved environmental sanitation on diarrhoeal diseases in rural Malawi. The study demonstrates the feasibility of using such an approach to evaluate two levels of water supply and sanitation service quickly and at moderate cost. Sample sizes would need to be increased substantially to evaluate multiple levels of service or to investigate interactions between water supply and sanitation. The results indicate that children living in families who use good quality water supplies and latrines experience 20% less diarrhoea as reported to the health clinics during the warm, rainy season. PMID:3418292

  20. [Relations between extraction of wisdom teeth and temporomandibular disorders: a case/control study].

    PubMed

    Duval, Florian; Leroux, Agathe; Bertaud, Valérie; Meary, Fleur; Le Padellec, Clément; Refuveille, Laura; Lemaire, Arnaud; Sorel, Olivier; Chauvel-Lebret, Dominique

    2015-09-01

    The aim of this study was to assess the impact of extraction of third molars on the occurrence of temporo-mandibular disorders (TMD). A review of the literature and a case-control study have been conducted. The case-control study compares the frequency of extraction of third molars between the sample with TMD (case) and the sample without TMD (control). The proportion of patients who had undergone extractions of wisdom teeth was higher in the case group than in the control group. The difference was statistically significant when patients had undergone extraction of all four wisdom teeth or when the extraction of four wisdom teeth underwent in one sitting or under general anesthesia. The study of patients in case sample shows that all signs of TMD were more common in patients who had undergone extractions in several sessions and under local anesthesia. The temporomandibular joint sounds are significantly more frequent with local anesthesia. In the case group, 85 to 92% of patients have parafunctions and 5 to 11% have malocclusion. This demonstrates the multifactorial etiology of temporomandibular disorders.

  1. Risk factors for ovarian cancer: a case-control study.

    PubMed

    Booth, M; Beral, V; Smith, P

    1989-10-01

    A hospital-based case-control study of ovarian cancer was conducted in London and Oxford between October 1978 and February 1983. Menstrual characteristics, reproductive and contraceptive history and history of exposure to various environmental factors were compared between 235 women with histologically diagnosed epithelial ovarian cancer and 451 controls. High gravidity, hysterectomy, female sterilisation and oral contraceptive use were associated with a reduced risk of ovarian cancer. Infertility and late age at menopause were associated with an increase in risk. While these factors were related, they were each found to be independently associated with ovarian cancer risk after adjusting for the effect of the other factors.

  2. Cancer and polluted work places: a case-control study.

    PubMed

    Kjuus, H; Lislerud, A; Lyngdal, P T; Omland, H; Stave, O; Langård, S

    1982-02-01

    The possible association between selected cancers and polluted work places has been studied in a hospital-based, case-control study. By dividing all jobs in the participants working career into "polluted" and "clean", a crude measure for the total industrial exposure a worker experiences throughout his life was established. Among 103 age-matched, case-control pairs the overall estimated relative risk (RR) for exposed subjects (greater than or equal to 10 years in a polluted work place) of developing cancer compared to nonexposed (less than 10 years in a polluted work place) was 1.1. The only subgroup where a significant difference was found between the cases and the controls was the lung cancer subgroup (RR = 4.0, p = 0.02, two-tailed). When the 30 lung cancer cases were compared to an alternative control group consisting of 60 subjects matched for age and smoking habits, an estimated RR of 4.5 was found. A moderate, but not significant association between lung cancer and definite asbestos exposure was also found (RR: 2.3). As most workers are exposed to a variety of industrial agents throughout their working careers, further development of methods for characterizing combined exposures are needed, both for retrospective and prospective purposes. PMID:7068240

  3. Case-control study of dementia of the Alzheimer type

    SciTech Connect

    French, L.R.; Schuman, L.M.; Mortimer, J.A.; Hutton, J.T.; Boatman, R.A.; Christians, B.

    1985-03-01

    A case-control study to assess factors of possible etiologic significance to dementia of the Alzheimer type was conducted with 78 male cases diagnosed in 1979-1982 at the Veterans Administration Medical Center in Minneapolis, Minnesota and age-race-sex-matched hospital and neighborhood controls (14 of 16 autopsied cases were histopathologically confirmed). Information was obtained on variables relevant to vital, genetic, and immunologic hypotheses, and on possible occupational and environmental exposures, drug use, psychologic stress, smoking, and alcohol consumption. The only major difference between patients with dementia of the Alzheimer type and controls was a significantly greater occurrence of antecedent head trauma in the patients (odds ratio = 4.50). This finding is consistent with the literature on posttraumatic dementia but its importance is presently unclear.

  4. Case-control association studies with matching and genomic controlling.

    PubMed

    Lee, Wen-Chung

    2004-07-01

    Family-based association studies have gained in popularity for mapping disease-susceptibility gene(s) of complex diseases. However, recruiting family controls is often more difficult than recruiting unrelated controls. The author proposes a case-control study, where the possible biases due to population stratification are controlled by matching in the design stage and by genomic controlling in the data-analytic stage. The matching is based on a set of "stratum-delineating variables," such as, race, ethnicity, nationality, ancestry, and birthplace; and the genomic controlling is based on typing a number of null markers across the genome and applying the principle of multiplicative scaling of chi-square distribution. It pays to match carefully to have a higher proportion of correctly matched sets, as computer simulation showed that this would increase the power of the study. If matching is crude, one loses power but still has the correct type I error rate after genomic controlling. Power studies showed that the numbers of affected subjects required for the pair-matched study are comparable to those required by the case-parents design, if the study was conducted in a homogeneous population. As the (control-to-case) matching ratio increases, the number of affected subjects required decreases. With matching ratio tending toward infinity, the number required shrinks roughly by half. The case-control study with matching and genomic controlling frees us from family bondage, and the genetic problem as complicated as mapping genes can now be studied using simple epidemiologic methods. PMID:15185398

  5. Leptospira Exposure and Gardeners: A Case-Control Seroprevalence Study

    PubMed Central

    Alvarado-Esquivel, Cosme; Hernandez-Tinoco, Jesus; Sanchez-Anguiano, Luis Francisco; Ramos-Nevarez, Agar; Cerrillo-Soto, Sandra Margarita; Guido-Arreola, Carlos Alberto

    2016-01-01

    Background Leptospira can be found in soil. However, it is unclear whether occupational exposure to soil may represent a risk for Leptospira infection in humans. Therefore, we sought to determine the association of Leptospira IgG seroprevalence with the occupation of gardener, and to determine the epidemiological characteristics of gardeners associated with Leptospira exposure. Methods We performed a case-control study in 168 gardeners and 168 age- and gender-matched control subjects without gardening occupation in Durango City, Mexico. The seroprevalence of anti-Leptospira IgG antibodies in cases and controls was determined using an enzyme immunoassay. Bivariate and multivariate analyses were used to assess the association of Leptospira exposure and the characteristics of the gardeners. Results Anti-Leptospira IgG antibodies were found in 10 (6%) of 168 gardeners and in 15 (8.9%) of 168 control subjects (odds ratio (OR): 0.64; 95% confidence interval (CI): 0.28 - 1.48; P = 0.40). Multivariate analysis showed that Leptospira seropositivity was positively associated with female gender (OR: 5.82; 95% CI: 1.11 - 30.46; P = 0.03), and negatively associated with eating while working (OR: 0.21; 95% CI: 0.05 - 0.87; P = 0.03). In addition, multivariate analysis showed that high anti-Leptospira levels were associated with consumption of boar meat (OR: 28.00; 95% CI: 1.20 - 648.80; P = 0.03). Conclusions This is the first case-control study of Leptospira exposure in gardeners. Results do not support an association of Leptospira exposure with the occupation of gardener. However, further studies to confirm the lack of this association are needed. The potential role of consumption of boar meat in Leptospira infection deserves further investigation. PMID:26668679

  6. Functional Impairment in Adult Sleepwalkers: A Case-Control Study

    PubMed Central

    Lopez, Regis; Jaussent, Isabelle; Scholz, Sabine; Bayard, Sophie; Montplaisir, Jacques; Dauvilliers, Yves

    2013-01-01

    Study Objectives: To investigate the restorative quality of sleep and daytime functioning in sleepwalking adult patients in comparison with controls. Design: Prospective case-control study. Setting: Data were collected at the Sleep Disorders Center, Hôpital-Gui-de Chauliac, Montpellier, France between June 2007 and January 2011. Participants: There were 140 adult sleepwalkers (100 (median age 30 y, 55% male) in whom primary SW was diagnosed) who underwent 1 night of video polysomnography. All patients participated in a standardized clinical interview and completed a battery of questionnaires to assess clinical characteristics of parasomnia, daytime sleepiness, fatigue, insomnia, depressive and anxiety symptoms, and health-related quality of life. Results were compared with those of 100 sex- and age-matched normal controls. Interventions: N/A. Measurements and Results: Of the sleepwalkers, 22.3% presented with daily episodes and 43.5% presented with weekly episodes. Median age at sleepwalking onset was 9 y. Familial history of sleepwalking was reported in 56.6% of sleepwalkers and violent sleep related behaviors in 57.9%, including injuries requiring medical care for at least one episode in 17%. Significant associations were found between sleepwalking and daytime sleepiness, fatigue, insomnia, depressive and anxiety symptoms, and altered quality of life. Early-onset sleepwalkers had higher frequency of violent behaviors and injuries. Sleepwalkers with violent behaviors had higher frequency of sleep terrors and triggering factors, with greater alteration in health-related quality of life. Conclusion: Adult sleepwalking is a potentially serious condition that may induce violent behaviors, self-injury or injury to bed partners, sleep disruption, excessive daytime sleepiness, fatigue, and psychological distress, all of which affect health-related quality of life. Citation: Lopez R; Jaussent I; Scholz S; Bayard S; Montplaisir J; Dauvilliers Y. Functional impairment in

  7. A Bayesian hierarchical approach for combining case-control and prospective studies.

    PubMed

    Müller, P; Parmigiani, G; Schildkraut, J; Tardella, L

    1999-09-01

    Motivated by the absolute risk predictions required in medical decision making and patient counseling, we propose an approach for the combined analysis of case-control and prospective studies of disease risk factors. The approach is hierarchical to account for parameter heterogeneity among studies and among sampling units of the same study. It is based on modeling the retrospective distribution of the covariates given the disease outcome, a strategy that greatly simplifies both the combination of prospective and retrospective studies and the computation of Bayesian predictions in the hierarchical case-control context. Retrospective modeling differentiates our approach from most current strategies for inference on risk factors, which are based on the assumption of a specific prospective model. To ensure modeling flexibility, we propose using a mixture model for the retrospective distributions of the covariates. This leads to a general nonlinear regression family for the implied prospective likelihood. After introducing and motivating our proposal, we present simple results that highlight its relationship with existing approaches, develop Markov chain Monte Carlo methods for inference and prediction, and present an illustration using ovarian cancer data. PMID:11315018

  8. Direct assessment of multiple testing correction in case-control association studies with related individuals.

    PubMed

    Wang, Zuoheng

    2011-01-01

    Genome-wide association studies typically test large numbers of genetic variants in association with trait values. It is well known that linkage disequilibrium (LD) between nearby markers tends to introduce correlation among association tests. Failure to properly adjust for multiple comparisons can lead to false-positive results or missing true-positive signals. The Bonferroni correction is generally conservative in the presence of LD. The permutation procedure, although has been widely employed to adjust for correlated tests, is not applicable when related individuals are included in case-control samples. With related individuals, the dependence among relatives' genotypes can also contribute to the correlation between tests. We present a new method P(norm) to correct for multiple hypothesis testing in case-control association studies in which some individuals are related. The adjustment with P(norm) simultaneously accounts for two sources of correlations of the test statistics: (1) LD among genetic markers (2) dependence among genotypes across related individuals. Using simulated data based on the International HapMap Project, we demonstrate that it has better control of type I error and is more powerful than some of the recently developed methods. We apply the method to a genome-wide association study of alcoholism in the GAW 14 COGA data set and detect genome-wide significant association. PMID:21181898

  9. Risk Factors of Streptococcus suis Infection in Vietnam. A Case-Control Study

    PubMed Central

    Ho, Dang Trung Nghia; Le, Thi Phuong Tu; Wolbers, Marcel; Cao, Quang Thai; Nguyen, Van Minh Hoang; Tran, Vu Thieu Nga; Le, Thi Phuong Thao; Nguyen, Hoan Phu; Tran, Thi Hong Chau; Dinh, Xuan Sinh; To, Song Diep; Hoang, Thi Thanh Hang; Hoang, Truong; Campbell, James; Nguyen, Van Vinh Chau; Nguyen, Tran Chinh; Nguyen, Van Dung; Ngo, Thi Hoa; Spratt, Brian G.; Tran, Tinh Hien; Farrar, Jeremy; Schultsz, Constance

    2011-01-01

    Background Streptococcus suis infection, an emerging zoonosis, is an increasing public health problem across South East Asia and the most common cause of acute bacterial meningitis in adults in Vietnam. Little is known of the risk factors underlying the disease. Methods and Findings A case-control study with appropriate hospital and matched community controls for each patient was conducted between May 2006 and June 2009. Potential risk factors were assessed using a standardized questionnaire and investigation of throat and rectal S. suis carriage in cases, controls and their pigs, using real-time PCR and culture of swab samples. We recruited 101 cases of S. suis meningitis, 303 hospital controls and 300 community controls. By multivariate analysis, risk factors identified for S. suis infection as compared to either control group included eating “high risk” dishes, including such dishes as undercooked pig blood and pig intestine (OR1 = 2.22; 95%CI = [1.15–4.28] and OR2 = 4.44; 95%CI = [2.15–9.15]), occupations related to pigs (OR1 = 3.84; 95%CI = [1.32–11.11] and OR2 = 5.52; 95%CI = [1.49–20.39]), and exposures to pigs or pork in the presence of skin injuries (OR1 = 7.48; 95%CI = [1.97–28.44] and OR2 = 15.96; 95%CI = [2.97–85.72]). S. suis specific DNA was detected in rectal and throat swabs of 6 patients and was cultured from 2 rectal samples, but was not detected in such samples of 1522 healthy individuals or patients without S. suis infection. Conclusions This case control study, the largest prospective epidemiological assessment of this disease, has identified the most important risk factors associated with S. suis bacterial meningitis to be eating ‘high risk’ dishes popular in parts of Asia, occupational exposure to pigs and pig products, and preparation of pork in the presence of skin lesions. These risk factors can be addressed in public health campaigns aimed at preventing S. suis infection

  10. Neurocysticercotic Calcifications and Hippocampal Sclerosis: A Case-Control Study

    PubMed Central

    Yasuda, Clarissa Lin; Coan, Ana Carolina; Secolin, Rodrigo; Luiz Cunha da Costa, Alberto; Cendes, Fernando

    2015-01-01

    Objective The exact role of calcified neurocysticercotic lesions (CNLs) in epilepsy is yet unknown and controversial. Although the relationship between CNLs, epilepsy and mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS) has already been addressed, to our knowledge, no study has actually provided strong statistical evidence, nor reported the ODDS ratio for these associations. Therefore, we designed this case-control study to assess the likelihood of having MTLE-HS versus other forms of epilepsy in the presence of CNLs. Methods In this case-control study we included 119 consecutive patients with epilepsy and 106 disease controls (headache) with previous CT scans. We subdivided cases into MTLE-HS and other epilepsies. We used brain CT scans to define presence or absence of CNLs. After exploratory analyses, we used logistic regression to analyze the association between CNLs, epilepsy subgroups and disease controls. Results CNLs were found in 31.09% of cases and in 11.32% of controls (p<0.001). The initial analysis comparing epilepsy versus controls revealed a significant association between CNLs and epilepsy (OR = 5.32; 95%CI = 2.43-11.54; p<0.001). However, when we compared MTLE-HS versus other epilepsies versus controls we confirmed that CNLs were associated with MTLE-HS (OR = 11.27, 95%CI = 4.73-26.85; p<0.001) but other epilepsies were not. We found no difference in the CNLs load and no difference in the location of the CNLs when we compared patients with MTLE-HS, other epilepsies and disease controls. Significance The inclusion of controls allowed us to estimate the likelihood of having epilepsy in the presence of CNLs. We found that patients with CNLs were 11 times more likely to have MTLE-HS; however, the presence of CNLs did not change the odds of having other types of epilepsy. These findings raise the possibility of neurocysticercosis playing a role in the pathophysiology of MTLE-HS and need further confirmation in other series. PMID

  11. Social aspects of chronic duodenal ulcer. A case control study.

    PubMed

    Nasiry, R; Piper, D W

    1983-01-01

    A case-control study of 80 patients with duodenal ulcer and 80 community controls was undertaken to compare these two groups regarding social and environmental factors including socio-economic status, marital status, country of birth, childhood and family factors. An increased risk of duodenal ulcer was associated with status incongruity in males; the male patients, when matched on suburb of residence, having lower status occupations than controls, and when matched on occupational status, tending to have lower educational levels than controls. Being unmarried was associated with an increased risk of duodenal ulcer in females. The number of siblings was also a risk factor in the male patients, those with more than 5 siblings being at an increased risk. Factors not associated with duodenal ulcer included country of birth, childhood happiness, sibling sequence and family stability. In conclusion, the factors associated with chronic duodenal ulcer were found predominantly in adult life and could produce their adverse effects by causing chronic stress which may be more relevant than acute stress as produced by major life events.

  12. Risk factors for heatstroke. A case-control study.

    PubMed

    Kilbourne, E M; Choi, K; Jones, T S; Thacker, S B

    1982-06-25

    To identify risk factors associated with heatstroke, a case-control study in St Louis and Kansas City, Mo, was conducted during July and August 1980. Questionnaire data were gathered for 156 persons with heatstroke (severe heat illness with documented hyperthermia) and 462 control subjects matched by age, sex, and neighborhood of residence. A stepwise linear logistic regression procedure was used to identify factors significantly associated with heatstroke. Alcoholism, living on the higher floors of multistory buildings, and using major tranquilizers (phenothiazines, butyrophenones, or thioxanthenes) were factors associated with increased risk. Factors associated with decreased risk were using home air conditioning, spending more time in air-conditioned places, and living in a residence well shaded by trees and shrubs. Being able to care for oneself, characteristically undertaking vigorous physical activity, but reducing such activity during the heat, and taking extra liquid were also associated with decreased risk. Our findings also suggest effective preventive measures. During a heat wave, the greatest attention should be directed toward high-risk groups, and relief efforts should include measures shown to be associated with reduced risk. PMID:7087076

  13. [Cleft lip and palate: case-control study].

    PubMed

    Loffredo, L de C; de Souza, J M; Yunes, J; Freitas, J A; Spiri, W C

    1994-06-01

    This study relates to a case-control analysis for the purpose of verifying the association between oral clefts and possible risk factors. The analysed variables were: place of mother's residence (urban/rural), pollution, parental diseases, mother's diseases during the first four months of pregnancy, intake of drugs related to this period, heredity, smoking habits, alcohol consumption and X-ray examinations during pregnancy or X-ray examinations prior to pregnancy. There were 450 cases of clefts of whom 354 had a cleft lip with or without cleft palate and 96 had a cleft palate. The relative risk (RR) for each variable by was estimated points and at a 95% of confidence interval and multivariate analysis was applied. As regards cleft lip with or without cleft palate, the risk factors are heredity (RR = 4.96), epilepsy in the mother (RR = 2.39) and the intake of drugs such as anti-inflammatory substance in the first four months of pregnancy (RR = 2.59). Related to cleft palate, the risk factors are heredity (RR = 2.82) and pollution (RR = 2.58).

  14. Micronutrients and oral clefts: a case-control study.

    PubMed

    McKinney, C M; Chowchuen, B; Pitiphat, W; Derouen, T; Pisek, A; Godfrey, K

    2013-12-01

    Little is known about oral clefts in developing countries. We aimed to identify micronutrient-related and environmental risk factors for oral clefts in Thailand. We tested hypotheses that maternal exposure during the periconceptional period to multivitamins or liver consumption would decrease cleft lip with or without cleft palate (CL ± P) risk and that menstrual regulation supplements would increase CL ± P risk. We conducted a multisite hospital-based case-control study in Thailand. We enrolled cases with CL ± P and 2 live births as controls at birth from the same hospital. Mothers completed a questionnaire. Conditional logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). Eighty-six cases and 172 controls were enrolled. Mothers who took a vitamin (adjusted OR, 0.39; 95% CI: 0.16, 0.94) or ate liver (adjusted OR, 0.26; 95% CI: 0.12, 0.57) were less likely than those who did not to have an affected child. Mothers who took a menstrual regulation supplement were more likely than mothers who did not to have an affected child. Findings did not differ for infants with a family history of other anomalies or with isolated CL ± P. If replicated, our finding that liver decreases CL ± P risk could offer a low-cost primary prevention strategy. PMID:24097855

  15. Case-control study of diet and mesothelioma in Louisiana.

    PubMed

    Schiffman, M H; Pickle, L W; Fontham, E; Zahm, S H; Falk, R; Mele, J; Correa, P; Fraumeni, J F

    1988-05-15

    Data were analyzed from a case-control interview study of malignant mesothelioma in Louisiana, which gathered information on usual diet and on lifetime occupational exposure to asbestos. Thirty-seven patients with malignant mesothelioma of the pleura (n = 32) or peritoneum (n = 5) were matched to controls according to age, sex, race, and factors related to case ascertainment (hospital and date of diagnosis, or parish and date of death). Twenty-one of the 37 cases were judged by masked occupational review to have been exposed to asbestos (57%), compared to seven of 37 controls (19%). Seven additional cases and 10 additional controls had occupational histories suggestive of asbestos exposure. With regard to usual diet before illness, cases reported less frequent consumption of homegrown produce (p = 0.005), cruciferous vegetables (p = 0.005), and all vegetables combined (p = 0.09) than did the controls. An estimate of usual carotene intake was also significantly lower in cases (p = 0.03). Dose-dependent reductions in risk were seen with increasing consumption of vegetables, especially cruciferous vegetables (p for trend = 0.013). These associations were not explained by differences in asbestos exposure as measured by the occupational review. The results indicate that consumption of vegetables or some vegetable-related constituent may have a protective effect on developing mesothelioma.

  16. Violence against Women and Gastroschisis: A Case-Control Study

    PubMed Central

    Ortega-García, Juan Antonio; Soldin, Offie P.; Sánchez-Sauco, Miguel Felipe; Cánovas-Conesa, Alicia; Gomaríz-Peñalver, Virtudes; Jaimes-Vega, Diana Carolina; Perales, Joseph E.; Cárceles-Alvarez, Alberto; Martínez-Ros, Maria Teresa; Ruiz, Daniel

    2013-01-01

    Background: Gastroschisis, a birth defect characterized by herniated fetal abdominal wall, occurs more commonly in infants born to teenage and young mothers. Ischemia of the vascular vitelline vessels is the likely mechanism of pathogenesis. Given that chronic stress and violence against women are risk factors for cardiovascular disease we explored whether these may represent risk factors for gastroschisis, when they occur during pregnancy. A case-control study was conducted, with 15 incident cases of children born with gastroschisis in the Region of Murcia, Spain, from December 2007 to June 2013. Forty concurrent controls were recruited at gestation weeks 20–24 or post-partum. All mothers of cases and controls completed a comprehensive, in-person, ‘green sheet’ questionnaire on environmental exposures. Results: Mothers of children with gastroschisis were younger, smoked more cigarettes per week relative to controls, were exposed to higher amounts of illegal drugs, and suffered from domestic violence more frequently than the controls. Multivariable logistic regression analysis highlights periconceptional ‘gender-related violence’ (OR: 16.6, 95% CI 2.7 to 101.7) and younger maternal age (OR 1.1, 95% CI 1.0–1.3). Conclusions: Violence against pregnant women is associated with birth defects, and should be studied in more depth as a cause-effect teratogenic. Psychosocial risk factors, including gender-based violence, are important for insuring the health and safety of the pregnant mother and the fetus. PMID:24142184

  17. Tuberculosis awareness in Gezira, Sudan: knowledge, attitude and practice case-control survey.

    PubMed

    Suleiman, M M A; Sahal, N; Sodemann, M; Elsony, A; Aro, A R

    2014-03-13

    This case-control study aimed to assess tuberculosis (TB) awareness and its associated sociodemographic characteristics in Gezira, Sudan. New smear-positive TB patients registered in Gezira in 2010 (n = 425) and age-matched controls who attended the same health facilities for other reasons (n = 850) formed the study sample. Awareness was measured using a modified standard World Health Organization TB knowledge, attitude and practice instrument. There was no significant difference between TB cases and the controls in overall levels of TB awareness. About two-thirds of TB cases and controls had good TB awareness. Respondents' sex was associated with awareness among the controls. Age, level of education, type of residence and type of occupation were significantly associated with TB awareness, whereas marital status had no effect. The good level of TB awareness found among TB cases and controls is a baseline for further TB awareness-raising among the Gezira population.

  18. Salivirus in Children and Its Association with Childhood Acute Gastroenteritis: A Paired Case-Control Study.

    PubMed

    Yu, Jie-Mei; Ao, Yuan-Yun; Liu, Na; Li, Li-Li; Duan, Zhao-Jun

    2015-01-01

    Salivirus was recently discovered in children with gastroenteritis and in sewage. Though a causative role for salivirus in childhood gastroenteritis was suggested in the previous study, the relationship between salivirus and acute gastroenteritis has not yet been clearly clarified. The sewage strain reported by Ng, although represented by incomplete genome sequencing data, was distinct from previously reported saliviruses, and had not previously been detected in humans. A case-control study examining 461 paired stool samples from children with diarrhea and healthy controls (1:1) was conducted in this study. Also, common diarrheal viruses were detected and complete genome of a salivirus was determined. Results showed that salivirus was detected in 16 (3.5%) and 13 (2.8%) of the case and control samples, respectively; no differences in detection rates (p=0.571) or mean values of viral loads (p=0.400) were observed between the groups. Multivariate Cox regression revealed no association between salivirus and gastroenteritis (p=0.774). The data also demonstrated that salivirus infection did not exacerbate clinical symptoms of gastroenteritis in children. Furthermore, complete genome sequence of a salivirus recovered from the feces of a child with diarrhea (i.e., SaliV-FHB) shared a 99% nucleotide identity with the sewage strain. In conclusion, a paired case-control study did not support a causative role for salivirus strains detected in this study with pediatric gastroenteritis. This study also demonstrated that all known saliviruses can be detected in the feces of children with or without gastroenteritis.

  19. The relationship between parenting, family interaction and childhood dental caries: a case-control study.

    PubMed

    de Jong-Lenters, M; Duijster, D; Bruist, M A; Thijssen, J; de Ruiter, C

    2014-09-01

    The aim of this case-control study was to explore the relationship between parenting practices, parent-child interaction and childhood dental caries, using a sample of 5-8-year old children from the Netherlands. Cases were defined as children with four or more decayed, missing or filled teeth and controls were caries free. Cases (n = 28) and controls (n = 26) were recruited from a referral centre for paediatric dental care and a general dental practice, respectively. Parenting practices and parent-child interactions of the child's primary caregiver were observed using Structured Interaction Tasks and subsequently rated on seven dimensions: positive involvement, encouragement, problem-solving, discipline, monitoring, coercion and interpersonal atmosphere. All Structured Interaction Tasks were videotaped, and coded by trained and calibrated observers blind to the dental condition. Differences in parenting dimensions between cases and controls were analysed using multivariate analysis of variance, independent samples T-tests, χ(2)-tests and multiple logistic regression analyses. Controls had significantly higher scores on the dimensions positive involvement, encouragement, problem-solving and interpersonal atmosphere, compared to cases. Parents of controls were also less likely to show coercive behaviours. These associations remained statistically significant after adjustment for the mother's education level, tooth brushing frequency and the frequency of consuming sugary foods and drinks, except for coercion. There was no significant difference in discipline between cases and controls. In conclusion, this case-control study found a significant relationship between parenting practices, parent-child interaction quality and childhood dental caries. Our findings suggest that parenting practices may be an important factor to consider in caries preventive programs. PMID:24980791

  20. A case-control pilot study on n-3 polyunsaturated fatty acid as a negative risk factor for myocardial infarction.

    PubMed

    Oda, Eiji; Hatada, Katsuharu; Katoh, Kiminori; Kodama, Makoto; Nakamura, Yuichi; Aizawa, Yoshifusa

    2005-07-01

    The relation between n-3 polyunsaturated fatty acid (PUFA) and nonfatal myocardial infarction is still controversial. A multicenter case-control pilot study on n-3 PUFA as a negative risk factor for myocardial infarction was performed in Niigata prefecture. Seventy-three patients with acute myocardial infarction (AMI) and age and gender matched controls (n = 84) were recruited. Serum leptin levels were significantly higher in patients with AMI than the controls (8.1 +/- 6.7 ng/mL versus 5.8 +/- 3.7 ng/mL, P < 0.01), and serum high-density lipoprotein cholesterol (HDLc) levels were significantly lower in patients with AMI than the controls (46 +/- 10.5 mg/dL versus 60 +/- 15 mg/dL, P < 0.00001). Statistically significant differences were preserved in leptin and HDLc when the data were analyzed separately by gender. Serum levels (%weight) of linolenic acid (C18:3:n3), eicosapentaenoic acid (C20:5:n3), docosapentaenoic acid (C22:5:n3), and total n-3 PUFA were significantly lower in patients with AMI than the control group (P < 0.000001, < 0.05, < 0.05, < 0.05, respectively). The serum n-3 PUFA/saturated fatty acid (SF) ratio and n-3 PUFA/n-9 monounsaturated fatty acid (MUFA) ratio were significantly lower in patients with AMI than the controls (P < 0.05 and < 0.01, respectively). When the subjects were separated into two categories according to an n-3/n-6 PUFA ratio below 0.3 or above 0.3, patients with AMI were more frequently in the former while the controls were more frequently in the latter (P < 0.05). N-3 PUFA may be a negative risk factor for AMI. The results suggest leptin is a risk factor for AMI irrespective of ethnicity and gender. PMID:16157949

  1. Melanoma and occupation: results of a case-control study.

    PubMed Central

    Fritschi, L; Siemiatycki, J

    1996-01-01

    OBJECTIVES: Associations between occupational exposures and the occurrence of cutaneous melanoma were examined as part of a large population based case-control study of 19 cancer sites. METHODS: Cases were men aged 35 to 70 years old, resident in Montreal, Canada, with a new histologically confirmed cutaneous melanoma (n = 103). There were two control groups, a randomly selected population control group (n = 533), and a cancer control group (n = 533) randomly selected from among subjects with other types of cancer in the large study. Odds ratios for the occurrence of melanoma were calculated for each exposure circumstance for which there were more than four exposed cases (85 substances, 13 occupations, and 20 industries) adjusting for age, ethnicity, and number of years of schooling. RESULTS: Significantly increased risk of melanoma was found for exposure to four substances (fabric dust, plastic dust, trichloroethylene, and a group containing paints used on surfaces other than metal and varnishes used on surfaces other than wood), three occupations (warehouse clerks, salesmen, and miners and quarrymen), and two industries (clothing and non-metallic mineral products). CONCLUSIONS: Most of the occupational circumstances examined were not associated with melanoma, nor is there any strong evidence from previous research that any of those are risk factors. For the few occupational circumstances which were associated in our data with melanoma, the statistical evidence was weak, and there is little or no supporting evidence in the scientific literature. On the whole, there is no persuasive evidence of occupational risk factors for melanoma, but the studies have been too small or have involved too much misclassification of exposure for this conclusion to be definitive. PMID:8704857

  2. Determinants of Brushite Stone Formation: A Case-Control Study

    PubMed Central

    Siener, Roswitha; Netzer, Linda; Hesse, Albrecht

    2013-01-01

    Purpose The occurrence of brushite stones has increased during recent years. However, the pathogenic factors driving the development of brushite stones remain unclear. Methods Twenty-eight brushite stone formers and 28 age-, sex- and BMI-matched healthy individuals were enrolled in this case-control study. Anthropometric, clinical, 24 h urinary parameters and dietary intake from 7-day weighed food records were assessed. Results Pure brushite stones were present in 46% of patients, while calcium oxalate was the major secondary stone component. Urinary pH and oxalate excretion were significantly higher, whereas urinary citrate was lower in patients as compared to healthy controls. Despite lower dietary intake, urinary calcium excretion was significantly higher in brushite stone patients. Binary logistic regression analysis revealed pH>6.50 (OR 7.296; p = 0.035), calcium>6.40 mmol/24 h (OR 25.213; p = 0.001) and citrate excretion <2.600 mmol/24 h (OR 15.352; p = 0.005) as urinary risk factors for brushite stone formation. A total of 56% of patients exhibited distal renal tubular acidosis (dRTA). Urinary pH, calcium and citrate excretion did not significantly differ between patients with or without dRTA. Conclusions Hypercalciuria, a diminished citrate excretion and an elevated pH turned out to be the major urinary determinants of brushite stone formation. Interestingly, urinary phosphate was not associated with urolithiasis. The increased urinary oxalate excretion, possibly due to decreased calcium intake, promotes the risk of mixed stone formation with calcium oxalate. Neither dietary factors nor dRTA can account as cause for hypercalciuria, higher urinary pH and diminished citrate excretion. Further research is needed to define the role of dRTA in brushite stone formation and to evaluate the hypothesis of an acquired acidification defect. PMID:24265740

  3. [A case-control study of Parkinson's disease].

    PubMed

    Watanabe, K

    1994-01-01

    Lifestyles and risk factors liable to idiopathic Parkinson's disease (IPD) were evaluated in a case-control study. 95 cases were studied along with their matched (1:2) controls. Cases were diagnosed at the Department of Neurology, Hokkaido University. Each given case was matched to two resident controls according to sex, age (+/- 1 year) and location (residents in the Sapporo area). 218 questions about preclinical life events (diet; exercise and physique; alcohol and smoking; personal relations; personality etc.) were asked in a one-to-one interview conducted by 3 staff members. Univariate results: 1) Diet: From infancy to 40, there were deficient intakes of meat, fruit, milk and dairy products, particularly prior to pubescence. Dietary behaviors after 40 showed no association. 2) Alcohol and smoking: Cases tended to smoke and drink less. 3) Exercise and Physique: Cases were inclined to dislike sports/exercise, to be physically slow, to have poor athletic ability, to have poor flexibility in adolescence and to have fair skin. 4) Personal relations: Cases had a tendency not to read books/newspapers, write letters, use the telephone and visit friends/relatives. Cases also refused leadership roles. 5) Personality: Cases were apt to be unsociable, taciturn, unobliging, and to have slow speech. Multivariate models: In order to study the joint effects and the combined effects of the major variables identified in univariate results, unconditional logistic regression analysis was carried out. The 9 variables were screened using stepwise procedure. From these variables, 4 independent variables were selected: deficient intake of fruit from middle school to 19 years old, fair skin, poor letter-writing ability and unsociability. The 4 independent variables were applied to one model, and resulted in a combined odds ratio figure. When the cases have none of the 4 independent variables, the combined odds ratio figure is 1. If the cases have all of them, then the combined odds

  4. Risk factors for pituitary tumors: a case-control study.

    PubMed

    Schoemaker, Minouk J; Swerdlow, Anthony J

    2009-05-01

    Pituitary gland tumors are usually benign but are associated with substantial morbidity. Their etiology is largely unknown. We conducted a population-based case-control study of potential risk factors for pituitary tumors in Southeast England. Information on medical and reproductive history, female sex hormones, and cigarette smoking was collected by personal interview from 299 cases and 630 controls aged 18 to 59 years. Tumor risk was reduced in subjects reporting a past diagnosis of hay fever [odds ratio (OR), 0.7; 95% confidence interval (CI), 0.5-1.0] but not asthma or eczema. Risk was raised in women who were postmenopausal 1 year before diagnosis (OR, 3.2; 95% CI, 1.6-6.2), especially if menopause was surgically induced (OR, 6.7; 95% CI, 2.2-19.9) or occurred under age 40 years (OR, 7.5; 95% CI, 2.6-21.4). This effect remained when evaluating menopausal status 10 years before diagnosis. There was no association with parity overall, but risk was increased for first childbirth under age 20 years compared with nulliparity (OR, 3.4; 95% CI, 1.4-8.4). No significant association was observed with ever use of oral contraceptives or hormone replacement therapy, nor with cigarette smoking, past head injury, past diagnosis with epilepsy, or birth characteristics, except for an inverse association of risk with maternal age. This study suggests a raised risk of pituitary tumors in relation to surgically induced menopause, early postmenopausal age, and young age at childbirth, and possibly a reduced risk with hay fever and increasing maternal age. Reasons for these associations need further investigation, but some associations might be due to hormonal effects of an undiagnosed pituitary tumor.

  5. Case-control study of multiple myeloma and farming.

    PubMed Central

    Pearce, N. E.; Smith, A. H.; Howard, J. K.; Sheppard, R. A.; Giles, H. J.; Teague, C. A.

    1986-01-01

    A previous case-control study which utilised the occupational information available on the New Zealand Cancer Registry found an increased risk of multiple myeloma in agricultural workers consistent with previous findings in the United States. The findings are now presented for the second phase of the study which involved interviewing 76 cases of multiple myeloma (who had been included in the previous study) together with 315 controls with other types of cancer. The previous finding on an excess of farmers in the case group was confirmed by the interview data (odds ratio = 1.7, 95% confidence limits 1.0-2.9, P = 0.04). There were no significant differences between cases and controls regarding potential exposure to phenoxy herbicides or chlorophenols. There were also no significant differences regarding activities involving potential exposure to other agricultural chemicals, although the odds ratio for fencing work, which may involve exposure to arsenic and sodium pentachlorophenate, was 1.6 (95% confidence limits 0.9-2.7, P = 0.11). The odds ratios were significantly elevated for sheep farming (odds ratio = 1.9, 95% confidence limits 1.0-3.6, P = 0.04) and exposure to beef cattle (odds ratio = 1.7, 95% confidence limits 1.0-2.9, P = 0.05). The odds ratio was also elevated for persons reporting a history of hay fever (odds ratio = 1.9, 95% confidence limits 1.0-3.5, P = 0.05). Overall, these findings suggest that the search for the causes of elevated mortality in farmers from multiple myeloma should be directed to potential causes other than pesticide exposure. PMID:3756085

  6. Risk factors for psoriasis: A case-control study.

    PubMed

    Jankovic, Slavenka; Raznatovic, Milena; Marinkovic, Jelena; Jankovic, Janko; Maksimovic, Natasa

    2009-06-01

    A case-control study of 110 consecutive psoriatic outpatients and 200 unmatched controls was carried out in order to analyze the association of psoriasis with smoking habits, alcohol consumption, family history of psoriasis and stressful life events. Stressful life events were assessed with Paykel's Interview for Recent Life Events, a semi-structured interview covering 63 life events. According to our results, the risk of psoriasis is higher in urban dwellers (odds ratio [OR] = 3.61; 95% confidence interval [CI] = 0.99-13.18), patients who were divorced (OR = 5.69; 95% CI = 2.26-14.34) and those exposed to environmental tobacco smoke at home (OR = 2.29; 95% CI = 1.12-4.67). Alcohol consumption (OR = 2.55; 95% CI = 1.26-5.17), family history of psoriasis (OR = 33.96; 95% CI = 14.14-81.57) and change in work conditions (OR = 8.34; 95% CI = 1.86-37.43) are also risk factors for psoriasis. Separate analyses for men and women showed that the risk of developing psoriasis was stronger in men with a family history of psoriasis (OR = 30.39; 95% CI = 6.72-137.42) than in women (OR = 16.99; 95% CI = 7.21-40.07). The effect of environmental tobacco smoke at home was found only in women (OR = 2.44; 95% CI = 1.26-4.73). Future well-designed epidemiological studies need to be performed in order to determine whether lifestyle factors and stress could be risk factors triggering or aggravating psoriasis.

  7. Risk Factors for Pancreatic Cancer: Case-Control Study

    PubMed Central

    Hassan, Manal M.; Bondy, Melissa L.; Wolff, Robert A.; Abbruzzese, James L.; Vauthey, Jean-Nicolas; Pisters, Peter W.; Evans, Douglas B.; Khan, Rabia; Chou, Ta-Hsu; Lenzi, Renato; Jiao, Li; Li, Donghui

    2008-01-01

    OBJECTIVES Although cigarette smoking is the most well-established environmental risk factor for pancreatic cancer, the interaction between smoking and other risk factors has not been assessed. We evaluated the independent effects of multiple risk factors for pancreatic cancer and determined whether the magnitude of cigarette smoking was modified by other risk factors in men and women. METHODS We conducted a hospital-based case-control study involving 808 patients with pathologically diagnosed pancreatic cancer and 808 healthy frequency-matched controls. Information on risk factors was collected by personal interview, and unconditional logistic regression was used to determine adjusted odds ratios (AORs) by the maximum-likelihood method. RESULTS Cigarette smoking, family history of pancreatic cancer, heavy alcohol consumption (>60 mL ethanol/day), diabetes mellitus, and history of pancreatitis were significant risk factors for pancreatic cancer. We found synergistic interactions between cigarette smoking and family history of pancreatic cancer (AOR 12.8, 95% confidence interval [CI] 1.6–108.9) and diabetes mellitus (AOR 9.3, 95% CI 2.0–44.1) in women, according to an additive model. Approximately 23%, 9%, 3%, and 5% of pancreatic cancer cases in this study were related to cigarette smoking, diabetes mellitus, heavy alcohol consumption, and family history of pancreatic cancer, respectively. CONCLUSIONS The significant synergy between these risk factors suggests a common pathway for carcinogenesis of the pancreas. Determining the underlying mechanisms for such synergies may lead to the development of pancreatic cancer prevention strategies for high-risk individuals. PMID:17764494

  8. [Perinatal mortality risk factors in a case-control study].

    PubMed

    Ruelas-Orozco, G; Guzmán, J; Malacara, J M

    1985-03-01

    This work describes a cross-sectional case-control study conducted in a marginal area of the city of Leon, Guanajuato, Mexico, to identify risk factors for perinatal mortality. 104 deaths identified in the civil register as occurring during 1982 in the study area were each matched to 2 controls selected from the same district and with birth dates within 30 days of the case. Perinatal mortality was defined as occurring between the 27th week of pregnancy and the 7th day after birth. 39 factors were stuided, including 10 socioeconomic factors, 6 maternal factors such as weight, height, and smoking, 10 factors concerning obstetrical history, 4 factors related to pathology during pregnancy, 6 factors referring to labor and delivery, and 2 concerning medical attention. In the univariate analysis, 18 factors were significant: unmarried or illiterate mother, maternal age under 17 or over 35, more than 7 previous births, previous perinatal death, less than 30 weeks or more than 200 weeks between pregnancies, hypertension, hemorrhage in the 2nd half of pregnancy, morning edema of pregnancy, no prenatal care, and birth attended by midwife. Some factors were eliminated because they were found to be dependent on a 2nd factor, and factors linked to perinatal events were also eliminated. A final model achieved after discriminant function analysis included 8 risk factors for perinatal mortality: 1) less than 30 weeks between pregnancies 2) more than 200 weeks between pregnancies 3) hypertension during pregnancy 4) maternal age under 18 5) maternal age over 35 6) unmarried mother 7) previous fetal deaths and 8) no prenatal care.

  9. Multiple Sclerosis Associated Risk Factors: A Case-Control Study

    PubMed Central

    POOROLAJAL, Jalal; MAZDEH, Mehrdokht; SAATCHI, Mohammad; TALEBI GHANE, Elaheh; BIDERAFSH, Azam; LOTFI, Bahar; FERYADRES, Mohammad; PAJOHI, Khabat

    2015-01-01

    Background: Hamadan Province is one of the high-risk regions in Iran for Multiple sclerosis (MS). A majority of the epidemiological studies conducted in Iran addressing MS are descriptive. This study was conducted to assess MS and its associated risk factors in Hamadan Province, the west of Iran. Methods: This case-control study compared 100 patients with MS (case group) and 100 patients with acute infectious diseases (control group) from September 2013 to March 2014. A checklist was used to assess the demographic, medical, and family history of the patients. The Friedman-Rosenman questionnaire was also used to assess personality type. Statistical analysis was performed using logistic regression model with Stata 11 software program. Results: The adjusted odds ratio (OR) estimate of MS was 4.37 (95% CI: 2.33, 8.20) for females compared to males; 0.15 (95% CI: 0.06, 0.43) for people aged above 50 years compared to aged 14 to 29 years; 0.44 (95% CI: 0.21, 0.91) for overweight or obese people compared to normal weights. Crude OR indicated a significant association between the occurrence of MS and exclusive breast feeding, season of birth, and smoking. However, the association was not statistically significant after adjustment for other covariates. Conclusion: The risk of MS is significantly lower in male gender, obese/overweight, and old people. Furthermore, non-smoking, non-exclusive breast-feeding, and born in autumn may increase the risk of MS but need further investigation. However, long-term large prospective cohort studies are needed to investigate the true effect of the potential risk factors on MS. PMID:26744707

  10. A case-control study of gallbladder cancer in hungary.

    PubMed

    Nakadaira, Hiroto; Lang, Istvan; Szentirmay, Zoltan; Hitre, Erika; Kaster, Miklos; Yamamoto, Masaharu

    2009-01-01

    Our previous study indicated an association of chili pepper consumption with gallbladder cancer (GBC) in the presence of gallstones (GS) in Chile. We investigated whether or not a similar association was present in Hungary, where mortality from GBC is high and chili peppers are frequently consumed. In a case-control study, we compared 41 female GBC patients with GS and 30 gender and GS-matched hospital controls. Trained staff interviewed all subjects to determine socioeconomic status, family history, past history and life style habits (smoking, alcohol intake, dietary habits and elimination habits). Because mean ages differed significantly between the case and control groups, age-adjusted odds ratios (ORs) were calculated. A shorter education period (< 10 years / > or = 16 years) was indicated to be a risk factor (age-adjusted OR (95%CI): 3.2 (1.2-8.7)). In addition, the intake of Hungarian hot pepper (yes / no) was found to be significantly higher in the GBC cases than in controls (age-adjusted OR (95%CI): 8.4 (2.3-30.4)). There were no differences between the case and control groups for other variables. Multivariate logistic regression analysis retained only Hungarian hot pepper consumption as a significant independent risk factor for GBC. Its age-adjusted OR was 16.2 (95%CI: 2.1-126.2), while there were no differences associated with low education, frequent consumption of fresh fruit and vegetables, low socioeconomic status or smoking. Hungarian hot pepper consumption was identified as a risk factor for GBC by multivariate logistic regression analysis.

  11. A Multicenter Trial Defining a Serum Protein Signature Associated with Pancreatic Ductal Adenocarcinoma

    PubMed Central

    Gerdtsson, Anna S.; Malats, Núria; Säll, Anna; Real, Francisco X.; Porta, Miquel; Skoog, Petter; Persson, Helena; Wingren, Christer; Borrebaeck, Carl A. K.

    2015-01-01

    Background. Pancreatic ductal adenocarcinoma (PDAC) is an aggressive disease with rapid tumor progression and poor prognosis. This study was motivated by the lack of sensitive and specific PDAC biomarkers and aimed to identify a diagnostic, serum protein signature for PDAC. Methods. To mimic a real life test situation, a multicenter trial comprising a serum sample cohort, including 338 patients with either PDAC or other pancreatic diseases (OPD) and controls with nonpancreatic conditions (NPC), was analyzed on 293-plex recombinant antibody microarrays targeting immunoregulatory and cancer-associated antigens. Results. Serum samples collected from different hospitals were analyzed and showed that (i) sampling from five different hospitals could not be identified as a preanalytical variable and (ii) a multiplexed biomarker signature could be identified, utilizing up to 10 serum markers that could discriminate PDAC from controls, with sensitivities and specificities in the 91–100% range. The first protein profiles associated with the location of the primary tumor in the pancreas could also be identified. Conclusions. The results demonstrate that robust enough serum signatures could be identified in a multicenter trial, potentially contributing to the development of a multiplexed biomarker immunoassay for improved PDAC diagnosis. PMID:26587286

  12. A guide to organizing a multicenter clinical trial.

    PubMed

    Chung, Kevin C; Song, Jae W

    2010-08-01

    Multicenter clinical trials are important research tools. Planning a multicenter clinical trial is a long and arduous task that requires substantial preparation time. In this guide, the authors discuss the steps used to plan a multicenter clinical trial. A preplanning phase, which involves formulating and refining a research question and conducting pilot studies, is detailed, and the planning phase, which involves the acquisition of funding to support the coordination and preparation of a multicenter clinical trial, culminating in the submission of an R01 grant, is described. An essential asset to planning a multicenter clinical trial is the fluidity with which all collaborators work together toward a common vision. The philosophy among collaborators should be consensus and commitment and is emphasized by the development of a consensus assisted study protocol. Most important are the recruitment of centers and co-investigators who are dedicated, collaborative, and selfless in the team effort to achieve goals that cannot be reached by a single-center effort.

  13. Does Helicobacter pylori Exacerbate Gastric Mucosal Injury in Users of Nonsteroidal Anti-Inflammatory Drugs? A Multicenter, Retrospective, Case-Control Study

    PubMed Central

    Kono, Yoshiyasu; Okada, Hiroyuki; Takenaka, Ryuta; Miura, Ko; Kanzaki, Hiromitsu; Hori, Keisuke; Kita, Masahide; Tsuzuki, Takao; Kawano, Seiji; Kawahara, Yoshiro; Yamamoto, Kazuhide

    2016-01-01

    Background/Aims The interaction between nonsteroidal anti-inflammatory drugs (NSAIDs) and Helicobacter pylori remains controversial. We retrospectively investigated whether H. pylori infection exacerbates severe gastric mucosal injury among chronic NSAID users. Methods From January 2010 to December 2013, a total of 245 long-term NSAID (including low-dose aspirin) users who had undergone an esophagogastroduodenoscopy and had been evaluated for H. pylori infection were enrolled at Okayama University Hospital and Tsuyama Chuo Hospital. The degree of gastric mucosal injury was assessed according to the modified Lanza score (MLS). Severe gastric mucosal injury was defined as an MLS ≥4. Univariate and multivariate logistic regression analyses were performed. Results In the univariate analysis, age ≥75 years (odds ratio [OR], 2.4; 95% confidence interval [CI], 1.3 to 4.2), H. pylori-positivity (OR, 2.0; 95% CI, 1.2 to 3.5), and the concomitant use of proton pump inhibitors (PPIs) (OR, 0.48; 95% CI, 0.26 to 0.86) were significantly associated with severe gastric mucosal injury. The multivariate analysis was adjusted by age and sex and demonstrated that H. pylori-positivity (OR, 1.8; 95% CI, 1.0 to 3.3) and the concomitant use of PPIs (OR, 0.53; 95% CI, 0.28 to 0.99) significantly contributed to severe gastric mucosal injury. Conclusions H. pylori infection exacerbates severe gastric mucosal injury among chronic NSAID users. PMID:26087789

  14. Case-control study for colorectal cancer genetic susceptibility in EPICOLON: previously identified variants and mucins

    PubMed Central

    2011-01-01

    Background Colorectal cancer (CRC) is the second leading cause of cancer death in developed countries. Familial aggregation in CRC is also important outside syndromic forms and, in this case, a polygenic model with several common low-penetrance alleles contributing to CRC genetic predisposition could be hypothesized. Mucins and GALNTs (N-acetylgalactosaminyltransferase) are interesting candidates for CRC genetic susceptibility and have not been previously evaluated. We present results for ten genetic variants linked to CRC risk in previous studies (previously identified category) and 18 selected variants from the mucin gene family in a case-control association study from the Spanish EPICOLON consortium. Methods CRC cases and matched controls were from EPICOLON, a prospective, multicenter, nationwide Spanish initiative, comprised of two independent stages. Stage 1 corresponded to 515 CRC cases and 515 controls, whereas stage 2 consisted of 901 CRC cases and 909 controls. Also, an independent cohort of 549 CRC cases and 599 controls outside EPICOLON was available for additional replication. Genotyping was performed for ten previously identified SNPs in ADH1C, APC, CCDN1, IL6, IL8, IRS1, MTHFR, PPARG, VDR and ARL11, and 18 selected variants in the mucin gene family. Results None of the 28 SNPs analyzed in our study was found to be associated with CRC risk. Although four SNPs were significant with a P-value < 0.05 in EPICOLON stage 1 [rs698 in ADH1C (OR = 1.63, 95% CI = 1.06-2.50, P-value = 0.02, recessive), rs1800795 in IL6 (OR = 1.62, 95% CI = 1.10-2.37, P-value = 0.01, recessive), rs3803185 in ARL11 (OR = 1.58, 95% CI = 1.17-2.15, P-value = 0.007, codominant), and rs2102302 in GALNTL2 (OR = 1.20, 95% CI = 1.00-1.44, P-value = 0.04, log-additive 0, 1, 2 alleles], only rs3803185 achieved statistical significance in EPICOLON stage 2 (OR = 1.34, 95% CI = 1.06-1.69, P-value = 0.01, recessive). In the joint analysis for both stages, results were only significant for rs

  15. A Single-Question Screen for REM Sleep Behavior Disorder: A Multicenter Validation Study

    PubMed Central

    Postuma, Ronald B.; Arnulf, Isabelle; Hogl, Birgit; Iranzo, Alex; Miyamoto, Tomoyuki; Dauvilliers, Yves; Oertel, Wolfgang; Ju, Yo-El; Puligheddu, Monica; Jennum, Poul; Pelletier, Amelie; Wolfson, Christina; Leu-Semenescu, Smaranda; Frauscher, Birgit; Miyamoto, Masayuki; De Cock, Valerie Cochen; Unger, Marcus M.; Stiasny-Kolster, Karin; Fantini, Maria Livia; Montplaisir, Jacques Y.

    2014-01-01

    Background Idiopathic REM sleep behavior disorder (RBD) is a parasomnia that is an important risk factor for PD and Lewy body dementia. Its prevalence is unknown. One barrier to determining prevalence is that current screening tools are too long for large-scale epidemiologic surveys. Therefore, we designed the REM Sleep Behavior Disorder Single-Question Screen (RBD1Q), a screening question for dream enactment with a simple yes/no response. Methods Four hundred and eighty-four sleep-clinic– based participants (242 idiopathic RBD patients and 242 controls) completed the screen during a multicenter case-control study. All participants underwent a polysomnogram to define gold-standard diagnosis according to standard criteria. Results We found a sensitivity of 93.8% and a specificity of 87.2%. Sensitivity and specificity were similar in healthy volunteers, compared to controls or patients, with other sleep diagnoses. Conclusions A single-question screen for RBD may reliably detect disease, with psychometric properties favorably comparable to those reported for longer questionnaires. PMID:22729987

  16. Multicenter pediatric emergency medicine research and Rhode Island.

    PubMed

    Chun, Thomas H

    2014-01-01

    Multicenter clinical research studies are often needed to address issues of generalizability, conditions with low incidence, adequate statistical power, and potential study bias. While pediatric research networks began work in the 1950s, and Rhode Island physicians have contributed to many of these studies, pediatric emergency medicine (PEM) collaboratives are relative newcomers. Since the mid-1990s, Rhode Island pediatricians have contributed to multicenter studies of diabetic ketoacidosis, bronchiolitis, asthma, quality of PEM care, meningitis, brief interventions for substance use disorders, point-of-care ultrasound, and pre-hospital triage protocols. In 2011, Rhode Island Hospital joined the Pediatric Emergency Care Applied Research Network, the first federally funded pediatric emergency medicine network of its kind. Its mission is to perform high quality, high impact PEM research. Since joining the network, Rhode Island Hospital has quickly become a productive and valued member of the network, portending a bright future for multicenter PEM research in the Ocean State. PMID:24400311

  17. Multicenter pediatric emergency medicine research and Rhode Island.

    PubMed

    Chun, Thomas H

    2014-01-01

    Multicenter clinical research studies are often needed to address issues of generalizability, conditions with low incidence, adequate statistical power, and potential study bias. While pediatric research networks began work in the 1950s, and Rhode Island physicians have contributed to many of these studies, pediatric emergency medicine (PEM) collaboratives are relative newcomers. Since the mid-1990s, Rhode Island pediatricians have contributed to multicenter studies of diabetic ketoacidosis, bronchiolitis, asthma, quality of PEM care, meningitis, brief interventions for substance use disorders, point-of-care ultrasound, and pre-hospital triage protocols. In 2011, Rhode Island Hospital joined the Pediatric Emergency Care Applied Research Network, the first federally funded pediatric emergency medicine network of its kind. Its mission is to perform high quality, high impact PEM research. Since joining the network, Rhode Island Hospital has quickly become a productive and valued member of the network, portending a bright future for multicenter PEM research in the Ocean State.

  18. Serum Taurine and Stroke Risk in Women: A Prospective, Nested Case-Control Study

    PubMed Central

    Wu, Fen; Koenig, Karen L.; Zeleniuch-Jacquotte, Anne; Jonas, Saran; Afanasyeva, Yelena; Wójcik, Oktawia P.; Costa, Max; Chen, Yu

    2016-01-01

    Background Taurine (2-aminoethanesulfonic acid), a conditionally essential sulfur-containing amino acid, is mainly obtained from diet in humans. Experimental studies have shown that taurine’s main biological actions include bile salt conjugation, blood pressure regulation, anti-oxidation, and anti-inflammation. Methods We conducted a prospective case-control study nested in the New York University Women’s Health Study, a cohort study involving 14,274 women enrolled since 1985. Taurine was measured in pre-diagnostic serum samples of 241 stroke cases and 479 matched controls. Results There was no statistically significant association between serum taurine and stroke risk in the overall study population. The adjusted ORs for stroke were 1.0 (reference), 0.87 (95% CI, 0.59–1.28), and 1.03 (95% CI, 0.69–1.54) in increasing tertiles of taurine (64.3–126.6, 126.7–152.9, and 153.0–308.5 nmol/mL, respectively). A significant inverse association between serum taurine and stroke risk was observed among never smokers, with an adjusted OR of 0.66 (95% CI, 0.37–1.18) and 0.50 (95% CI, 0.26–0.94) for the second and third tertile, respectively (p for trend = 0.01), but not among past or current smokers (p for interaction < 0.01). Conclusions We observed no overall association between serum taurine and stroke risk, although a protective effect was observed in never smokers, which requires further investigation. Taurine, Stroke, Epidemiology, Prospective, Case-control study, NYUWHS. PMID:26866594

  19. The association between Anoplocephala perfoliata and colic in Swedish horses--a case control study.

    PubMed

    Back, H; Nyman, A; Osterman Lind, E

    2013-11-01

    A case-control study was performed to investigate the association between colic of all types in Swedish horses and infection with the equine tapeworm Anoplocephala perfoliata. Colic cases were defined by clinical signs consistent with the presence of abdominal pain, and the control horses had no signs of colic within the last year but attended a clinic for other reasons. Blood and fecal samples were collected by veterinarian from 67 horses with signs of colic and 67 control horses. The sera were analyzed using serodiagnostic assay anti-12/13 kDa IgG(T) ELISA. The fecal samples, 30 g from each horse, were analyzed with a modified sugar salt flotation method with a density of 1.280. A significant association was found between the presence of A. perfoliata eggs in feces and colic with a 16 times higher risk of colic if eggs had been observed in fecal samples. However, there was no significant association between colic and the median OD-values in the serological diagnosis, nor when recommended cut-offs were used. The study concludes that A. perfoliata is a risk factor for colic in Swedish horses and it suggests that the modified flotation method can be used as a diagnostic tool for identifying horses at risk.

  20. Clostridium difficile infection after adult autologous stem cell transplantation: A multicenter study of epidemiology and risk factors

    PubMed Central

    Dufresne, Simon F.; Hanna, David B.; Labbé, Annie-Claude; Treadway, Suzanne B.; Neofytos, Dionissios; Bélanger, Sylvie; Huff, Carol Ann; Laverdière, Michel; Marr, Kieren A.

    2013-01-01

    We sought to describe the epidemiology of Clostridium difficile infection (CDI) among adult recipients of autologous hematopoietic stem cell transplantation (auto HSCT) within the first year after HSCT in centers with variable epidemiology of hyper-toxigenic strains. A multicenter, retrospective nested case-control study was conducted among 873 auto HSCT recipients at Johns Hopkins Hospital (JHH, Baltimore, MD) and Hôpital Maisonneuve-Rosemont (HMR, Montreal, Canada) between 1/2003-12/2008. Despite center differences in the prevalence of NAP-1 strains over the time period (21-43% JHH; 80-84% HMR), the 1-year incidence of CDI was similar (6.2% JHH; 5.7% HMR). The median time to infection was 11 days (interquartile range [IQR] 1 to 27). In case control analysis, the following were predictors for CDI: grade 2 or higher mucositis (odds ratio [OR]: 3.00, P=0.02) and receipt of a 4th generation cephalosporin (OR: 2.76, P=0.04). Mucositis was the strongest predictor of risk for CDI in multivariate analysis (adjusted OR [AOR]: 2.77; P=0.03). CDI is a common and early complication of auto HSCT. Treatment-related gastrointestinal mucosal damage, in addition to the potentially modifiable risk of antimicrobial exposure, influence risk for CDI early post-auto HSCT. PMID:23916741

  1. Mass Spectrometry Imaging of Biological Tissue: An Approach for Multicenter Studies

    SciTech Connect

    Rompp, Andreas; Both, Jean-Pierre; Brunelle, Alain; Heeren, Ronald M.; Laprevote, Olivier; Prideaux, Brendan; Seyer, Alexandre; Spengler, Bernhard; Stoeckli, Markus; Smith, Donald F.

    2015-03-01

    Mass spectrometry imaging has become a popular tool for probing the chemical complexity of biological surfaces. This led to the development of a wide range of instrumentation and preparation protocols. It is thus desirable to evaluate and compare the data output from different methodologies and mass spectrometers. Here, we present an approach for the comparison of mass spectrometry imaging data from different laboratories (often referred to as multicenter studies). This is exemplified by the analysis of mouse brain sections in five laboratories in Europe and the USA. The instrumentation includes matrix-assisted laser desorption/ionization (MALDI)-time-of-flight (TOF), MALDI-QTOF, MALDIFourier transform ion cyclotron resonance (FTICR), atmospheric-pressure (AP)-MALDI-Orbitrap, and cluster TOF-secondary ion mass spectrometry (SIMS). Experimental parameters such as measurement speed, imaging bin width, and mass spectrometric parameters are discussed. All datasets were converted to the standard data format imzML and displayed in a common open-source software with identical parameters for visualization, which facilitates direct comparison of MS images. The imzML conversion also allowed exchange of fully functional MS imaging datasets between the different laboratories. The experiments ranged from overview measurements of the full mouse brain to detailed analysis of smaller features (depending on spatial resolution settings), but common histological features such as the corpus callosum were visible in all measurements. High spatial resolution measurements of AP-MALDI-Orbitrap and TOF-SIMS showed comparable structures in the low-micrometer range. We discuss general considerations for planning and performing multicenter studies in mass spectrometry imaging. This includes details on the selection, distribution, and preparation of tissue samples as well as on data handling. Such multicenter studies in combination with ongoing activities for reporting guidelines, a common

  2. Mass spectrometry imaging of biological tissue: an approach for multicenter studies.

    PubMed

    Römpp, Andreas; Both, Jean-Pierre; Brunelle, Alain; Heeren, Ron M A; Laprévote, Olivier; Prideaux, Brendan; Seyer, Alexandre; Spengler, Bernhard; Stoeckli, Markus; Smith, Donald F

    2015-03-01

    Mass spectrometry imaging has become a popular tool for probing the chemical complexity of biological surfaces. This led to the development of a wide range of instrumentation and preparation protocols. It is thus desirable to evaluate and compare the data output from different methodologies and mass spectrometers. Here, we present an approach for the comparison of mass spectrometry imaging data from different laboratories (often referred to as multicenter studies). This is exemplified by the analysis of mouse brain sections in five laboratories in Europe and the USA. The instrumentation includes matrix-assisted laser desorption/ionization (MALDI)-time-of-flight (TOF), MALDI-QTOF, MALDI-Fourier transform ion cyclotron resonance (FTICR), atmospheric-pressure (AP)-MALDI-Orbitrap, and cluster TOF-secondary ion mass spectrometry (SIMS). Experimental parameters such as measurement speed, imaging bin width, and mass spectrometric parameters are discussed. All datasets were converted to the standard data format imzML and displayed in a common open-source software with identical parameters for visualization, which facilitates direct comparison of MS images. The imzML conversion also allowed exchange of fully functional MS imaging datasets between the different laboratories. The experiments ranged from overview measurements of the full mouse brain to detailed analysis of smaller features (depending on spatial resolution settings), but common histological features such as the corpus callosum were visible in all measurements. High spatial resolution measurements of AP-MALDI-Orbitrap and TOF-SIMS showed comparable structures in the low-micrometer range. We discuss general considerations for planning and performing multicenter studies in mass spectrometry imaging. This includes details on the selection, distribution, and preparation of tissue samples as well as on data handling. Such multicenter studies in combination with ongoing activities for reporting guidelines, a common

  3. A Multicenter Reference Intervals Study for Specific Proteins in China

    PubMed Central

    Qin, Xuzhen; Tang, Guodong; Qiu, Ling; Li, Peng Chang; Xia, Liangyu; Chen, Ming; Tao, Zhihua; Li, Shijun; Liu, Min; Wang, Liang; Gao, Shang; Yu, Songlin; Cheng, Xinqi; Han, Jianhua; Hou, Li’an; Kawano, Reo; Ichihara, Kiyoshi

    2015-01-01

    Abstract A multicenter study conducted in healthy population of 6 cities from the 4 corners and central China for 7 serum-specific proteins to identify the sources of variation and establish the reference intervals on 2 automation platforms. A total of 3148 subjects aged 19 to 64 years old were enrolled in this study to ensure at least 120 participants in each 10-year age group and each city. The majority of samples were transported to central laboratory and measured on both Beckman AU5800 and Immage 800 analytical systems. Three-level nested ANOVA, multiple regression analysis, and the scatter plot were used to explore the variations from sex, age, region, BMI, cigarette smoking, and so on. The latent abnormal value exclusion (LAVE) method was applied at the time of computing RIs as a method for secondary exclusion. Regionality was not observed in any of the immunoassay in China. Variations for sex were significant for IgM among the immune analytes. For CRP and hsCRP results with turbidimetry method (Beckman Coulter AU5800) were lower than the nephelometry method (Beckman Immage). The LAVE method did not affect the RIs computed for the majority of analytes except C4, CRP, and hsCRP. In the scatter plot at the age of 45 years old C3, C4, and IgM reached an inflection point, accordingly RIs were separated by the age group. With the lack of regional differences and the well-standardized status of test results, the RIs of C3, IgG, IgA, IgM derived from this nationwide study can be used for the entire Chinese population. C4, CRP, and hsCRP were affected by different platforms and gender was a significant source of variation for IgM, so they had separated RIs. PMID:26656356

  4. A Multicenter Reference Intervals Study for Specific Proteins in China.

    PubMed

    Qin, Xuzhen; Tang, Guodong; Qiu, Ling; Li, Peng Chang; Xia, Liangyu; Chen, Ming; Tao, Zhihua; Li, Shijun; Liu, Min; Wang, Liang; Gao, Shang; Yu, Songlin; Cheng, Xinqi; Han, Jianhua; Hou, Li'an; Kawano, Reo; Ichihara, Kiyoshi

    2015-12-01

    A multicenter study conducted in healthy population of 6 cities from the 4 corners and central China for 7 serum-specific proteins to identify the sources of variation and establish the reference intervals on 2 automation platforms.A total of 3148 subjects aged 19 to 64 years old were enrolled in this study to ensure at least 120 participants in each 10-year age group and each city. The majority of samples were transported to central laboratory and measured on both Beckman AU5800 and Immage 800 analytical systems. Three-level nested ANOVA, multiple regression analysis, and the scatter plot were used to explore the variations from sex, age, region, BMI, cigarette smoking, and so on. The latent abnormal value exclusion (LAVE) method was applied at the time of computing RIs as a method for secondary exclusion.Regionality was not observed in any of the immunoassay in China. Variations for sex were significant for IgM among the immune analytes. For CRP and hsCRP results with turbidimetry method (Beckman Coulter AU5800) were lower than the nephelometry method (Beckman Immage). The LAVE method did not affect the RIs computed for the majority of analytes except C4, CRP, and hsCRP. In the scatter plot at the age of 45 years old C3, C4, and IgM reached an inflection point, accordingly RIs were separated by the age group.With the lack of regional differences and the well-standardized status of test results, the RIs of C3, IgG, IgA, IgM derived from this nationwide study can be used for the entire Chinese population. C4, CRP, and hsCRP were affected by different platforms and gender was a significant source of variation for IgM, so they had separated RIs. PMID:26656356

  5. Managing Multi-center Flow Cytometry Data for Immune Monitoring

    PubMed Central

    White, Scott; Laske, Karoline; Welters, Marij JP; Bidmon, Nicole; van der Burg, Sjoerd H; Britten, Cedrik M; Enzor, Jennifer; Staats, Janet; Weinhold, Kent J; Gouttefangeas, Cécile; Chan, Cliburn

    2014-01-01

    With the recent results of promising cancer vaccines and immunotherapy1–5, immune monitoring has become increasingly relevant for measuring treatment-induced effects on T cells, and an essential tool for shedding light on the mechanisms responsible for a successful treatment. Flow cytometry is the canonical multi-parameter assay for the fine characterization of single cells in solution, and is ubiquitously used in pre-clinical tumor immunology and in cancer immunotherapy trials. Current state-of-the-art polychromatic flow cytometry involves multi-step, multi-reagent assays followed by sample acquisition on sophisticated instruments capable of capturing up to 20 parameters per cell at a rate of tens of thousands of cells per second. Given the complexity of flow cytometry assays, reproducibility is a major concern, especially for multi-center studies. A promising approach for improving reproducibility is the use of automated analysis borrowing from statistics, machine learning and information visualization21–23, as these methods directly address the subjectivity, operator-dependence, labor-intensive and low fidelity of manual analysis. However, it is quite time-consuming to investigate and test new automated analysis techniques on large data sets without some centralized information management system. For large-scale automated analysis to be practical, the presence of consistent and high-quality data linked to the raw FCS files is indispensable. In particular, the use of machine-readable standard vocabularies to characterize channel metadata is essential when constructing analytic pipelines to avoid errors in processing, analysis and interpretation of results. For automation, this high-quality metadata needs to be programmatically accessible, implying the need for a consistent Application Programming Interface (API). In this manuscript, we propose that upfront time spent normalizing flow cytometry data to conform to carefully designed data models enables

  6. Biomass Fuel Smoke and Tuberculosis: A Case-Control Study.

    PubMed

    Haque, M A; Barman, N; Islam, M T; Mannan, M; Khan, M H; Karim, M R; Rob, M A; Hossain, M A

    2016-01-01

    This case control study was done to ascertain the association between exposures to biomass cooking fuel smoke and pulmonary tuberculosis. Cases were all newly diagnosed pulmonary tuberculosis patients, randomly collected from the Hospital (DOTS centers) Registry from January 2012 to June 2012 from two Upazillas of Sirajganj district, Bangladesh. A home visitation program was done subsequently. Healthy controls were recruited from the neighbourhood of each case through a predefined procedure. Total 276 new pulmonary tuberculosis cases and 276 neighbourhood controls were enrolled. A semi-structured questionnaire containing demographic information, smoking habits, cooking place, kitchen condition, use of biomass fuel for cooking was used for interview. Crude (unadjusted) odd ratios and their corresponding 95% confidence limits for independent variables were determined by binary logistic regression. All significant variables were entered into a multivariate conditional logistic regression model and a final fitted model was determined by backward elimination methods. In univariate analysis, member of a nuclear family {Unadjusted odd ratio (Unadj. OR) 1.570, 95% CI 1.008-2.44)}, having non-formal education (Unadj. OR 2.739, 95% CI 1.219, 6.153) or primary (Unadj. OR 3.407, 95% CI 1.492, 7.782) to secondary level (Unadj. OR 2.392, 95% CI 1.032, 5.544) education, using cow dung (Unadj. OR 3.961, 95% CI 1.267, 12.376) and biomass fuel i.e. plant origin (Unadj. OR 3.382, 95% CI 1.087, 10.518) for cooking, past smoker (Unadj. OR 2.504, 95% CI 1.061, 5.910), using open oven (Unadj. OR 3.109, 95% CI 0.995, 9.716), having small kitchen area (Unadj. OR 0.99, 95% CI 0.989, 0.999) all were significantly associated with tuberculosis. When all significant variables were entered into a multivariate conditional logistic regression model nuclear family {Adjusted odd ratio (Adj OR) 1.808, 95% CI 1.127, 2.9)}, primary level education (Adj OR 2.86, 95% CI 1.23, 6.647) and non formal

  7. Comparing apples and oranges: equating the power of case-control and quantitative trait association studies.

    PubMed

    Yang, Jian; Wray, Naomi R; Visscher, Peter M

    2010-04-01

    Genome-wide association studies have achieved unprecedented success in the identification of novel genes and pathways implicated in complex traits. Typically, studies for disease use a case-control (CC) design and studies for quantitative traits (QT) are population based. The question that we address is what is the equivalence between CC and QT association studies in terms of detection power and sample size? We compare the binary and continuous traits by assuming a threshold model for disease and assuming that the effect size on disease liability has similar feature as on QT. We derive the approximate ratio of the non-centrality parameter (NCP) between CC and QT association studies, which is determined by sample size, disease prevalence (K) and the proportion of cases (v) in the CC study. For disease with prevalence <0.1, CC association study with equal numbers of cases and controls (v=0.5) needs smaller sample size than QT association study to achieve equivalent power, e.g. a CC association study of schizophrenia (K=0.01) needs only approximately 55% sample size required for association study of height. So a planned meta-analysis for height on approximately 120,000 individuals has power equivalent to a CC study on 33,100 schizophrenia cases and 33,100 controls, a size not yet achievable for this disease. With equal sample size, when v=K, the power of CC association study is much less than that of QT association study because of the information lost by transforming a quantitative continuous trait to a binary trait. PMID:19918758

  8. Prevalence of Intestinal Protozoa among Saudi Patients with Chronic Renal Failure: A Case-Control Study.

    PubMed

    Hawash, Yousry A; Dorgham, Laila Sh; Amir, El-Amir M; Sharaf, Osama F

    2015-01-01

    It has been hypothesized that chronic renal failure (CRF) predisposes patients to infection with intestinal protozoa. We tested this hypothesis with a matched case-control study to determine the prevalence of these protozoa and their diarrhea associated symptoms among 50 patients with CRF (cases) from Taif, western Saudi Arabia. Fifty diarrheal patients without CRF were recruited in the study as controls. Participants were interviewed by a structured questionnaire and stool samples were collected. Samples were thoroughly examined with microscopy and three coproantigens detection kits. Enteric protozoa were detected in 21 cases and 14 controls. Blastocystis spp. were the most predominant parasite (16% in cases versus 8% in controls), followed by Giardia duodenalis (10% in cases versus 12% in controls) and Cryptosporidium spp. (10% in cases versus 6% in controls). Cyclospora cayetanensis was identified in two cases, while Entamoeba histolytica was described in one case and one control. Intestinal parasitism was positively associated with the male gender, urban residence, and travel history. Clinical symptoms of nausea/vomiting and abdominal pain were significantly varied between the parasitized cases and controls (P value ≤ 0.05). Given the results, we recommend screening all diarrheal feces for intestinal protozoa in the study's population, particularly those with CRF. PMID:26491455

  9. Robust Estimation for Secondary Trait Association in Case-Control Genetic Studies

    PubMed Central

    Tapsoba, Jean de Dieu; Kooperberg, Charles; Reiner, Alexander; Wang, Ching-Yun; Dai, James Y.

    2014-01-01

    Secondary trait genetic association provides insight into the genetic architecture of disease etiology but requires caution in estimation. Ignoring case-control sampling may introduce bias into secondary trait association. In this paper, we compare the efficiency and robustness of various inverse probability weighted (IPW) estimators and maximum likelihood (ML) estimators. ML methods have been proposed but require correct modeling of both the secondary and the primary trait associations for valid inference. We show that ML methods using a misspecified primary trait model can severely inflate the type I error. IPW estimators are typically less efficient than ML estimators but are robust against model misspecification. When the secondary trait is available for the entire cohort, the IPW estimator with selection probabilities estimated nonparametrically and the augmented IPW estimator improve efficiency over the simple IPW estimator. We conclude that in large genetic association studies with complex sampling schemes, IPW-based estimators offer flexibility and robustness, and therefore are a viable option for analysis. PMID:24723002

  10. Prevalence of Intestinal Protozoa among Saudi Patients with Chronic Renal Failure: A Case-Control Study.

    PubMed

    Hawash, Yousry A; Dorgham, Laila Sh; Amir, El-Amir M; Sharaf, Osama F

    2015-01-01

    It has been hypothesized that chronic renal failure (CRF) predisposes patients to infection with intestinal protozoa. We tested this hypothesis with a matched case-control study to determine the prevalence of these protozoa and their diarrhea associated symptoms among 50 patients with CRF (cases) from Taif, western Saudi Arabia. Fifty diarrheal patients without CRF were recruited in the study as controls. Participants were interviewed by a structured questionnaire and stool samples were collected. Samples were thoroughly examined with microscopy and three coproantigens detection kits. Enteric protozoa were detected in 21 cases and 14 controls. Blastocystis spp. were the most predominant parasite (16% in cases versus 8% in controls), followed by Giardia duodenalis (10% in cases versus 12% in controls) and Cryptosporidium spp. (10% in cases versus 6% in controls). Cyclospora cayetanensis was identified in two cases, while Entamoeba histolytica was described in one case and one control. Intestinal parasitism was positively associated with the male gender, urban residence, and travel history. Clinical symptoms of nausea/vomiting and abdominal pain were significantly varied between the parasitized cases and controls (P value ≤ 0.05). Given the results, we recommend screening all diarrheal feces for intestinal protozoa in the study's population, particularly those with CRF.

  11. HLA-DR EXPRESSION AS A BIOMARKER OF INFLAMMATION FOR MULTICENTER CLINICAL TRIALS OF OCULAR SURFACE DISEASE

    PubMed Central

    Epstein, Seth P.; Gadaria-Rathod, Neha; Wei, Yi; Maguire, Maureen G.; Asbell, Penny A.

    2014-01-01

    There are currently no validated minimally invasive objective metrics for the classification and evaluation of ocular surface diseases and/or for evaluating treatment efficacy. We thus sought to establish a standardized methodology for determining the relative amount of the inflammatory biomarker HLA-DR on the ocular surface and to evaluate the precision, reliability and repeatability of its use for large multicenter clinical trials and translational research studies of ocular surface disease. Multiple studies were conducted to establish a Standard Operating Procedure (SOP) for utilizing HLA-DR expression as a minimally invasive, objective, ocular surface inflammatory biomarker. The established SOPs provide specific guidelines for HLA-DR collection and analysis, in order to incorporate it reliably into multicenter clinical trials and/or translational research. Duplicate cell samples from impression cytology (IC) samples of both normal and dry eye individuals were collected and split to assess repeatability (between the splits and between the duplicate samples). To determine storage capability, one duplicate was stained immediately and the other after 30 days cold storage. To demonstrate the feasibility of the use of the SOP for a multicenter clinical trial, clinicians out-of-state were trained to collect IC samples, and the samples shipped to our Biomarker Laboratory, logged, processed and analyzed. Demonstration of the ability to incorporate of IC into a randomized double masked clinical trial of dry eye disease (DED) was performed. In all cases, processing and analyses were performed by a masked independent observer. The validity/viability of the SOPs was established by demonstrating that: 1) sufficient numbers of cells can be collected via IC; 2) the precision/repeatability of the relative biomarker expression quantified in samples; 3) personnel at distant sites can be taught to collect, store and ship samples successfully; 4) samples can be stored for up to 30

  12. Regulatory Cytokine Expression and Preterm Birth: Case-Control Study Nested in a Cohort

    PubMed Central

    Pereira, Thaís Basso de Brito; Thomaz, Erika Barbara Abreu Fonseca; do Nascimento, Flávia Raquel Fernandes; dos Santos, Ana Paula Silva de Azevedo; Batista, Rosângela Lucena Fernandes; Bettiol, Heloisa; Cavalli, Ricardo de Carvalho; Barbieri, Marco Antônio; da Silva, Antônio Augusto Moura

    2016-01-01

    Background Currently known risk factors explain only a small fraction of preterm birth (PTB). Previous PTB is one of the most important predictors. However, this information is not available in primiparous women. Few studies have looked at associations between regulatory cytokine expression (RCE) and PTB and the results are conflicting. Objective To investigate the association of RCE–Interleukin 10 (IL-10) and Transforming Growth Factor β (TGF-β)–with PTB, and to assess whether bacterial vaginosis (BV) is involved in this relationship. Methods This was a case-control study nested in a prospective cohort–called BRISA. Women with singleton pregnancies were interviewed from 22 to 25 weeks of gestational age (GA). Women were recruited from health services in São Luís, Brazil. A blood sample was collected and gynecological examination was performed. Serum IL-10 and TGF-β were determined using cytometric bead array. Nugent score >7 and/or the presence of clue cells were used for BV diagnosis. All PTB estimated by ultrasound dating performed before 20 weeks of gestational age were considered cases. Controls were selected by simple random sampling from the rest of the cohort, at a 2:1 ratio. Different models were tested, according to the main independent variable. Odds ratios (OR) and 95% confidence intervals (95%CI) were estimated by regression analyses. Results The study included 327 pregnant women, 109 cases and 218 controls. No associations were found between BV and PTB (P = 1.44; 95%CI: 0.51–3.77). Low levels of IL-10 (OR = 2.92 95%CI: 1.38–6.16) or TGF-β (OR = 16.90 95%CI: 6.42–44.51) or both simultaneously (OR = 77.16 95%CI: 7.99–744.88) were associated with increasing odds of PTB, even after adjustment for confounding. Conclusion Decreased RCE is a risk factor for PTB. This relationship, however, is not triggered by the presence of BV. Low IL-10/TGF-β levels from 22 to 25 weeks of GA could be used as early predictors of PTB. We suggest

  13. GATM polymorphism associated with the risk for statin-induced myopathy does not replicate in case-control analysis of 715 dyslipidemic individuals.

    PubMed

    Luzum, Jasmine A; Kitzmiller, Joseph P; Isackson, Paul J; Ma, Changxing; Medina, Marisa W; Dauki, Anees M; Mikulik, Eduard B; Ochs-Balcom, Heather M; Vladutiu, Georgirene D

    2015-04-01

    Statin-induced myopathy (SIM) is the most common reason for discontinuation of statin therapy. A polymorphism affecting the gene encoding glycine amidinotransferase (GATM rs9806699 G > A) was previously associated with reduced risk for SIM. Our objective was to replicate the GATM association in a large, multicenter SIM case-control study. Mild and severe SIM cases and age- and gender-matched controls were enrolled. Participants were genotyped, and associations were tested (n = 715) using chi-square and logistic regression with consideration for SIM severity and exclusion of subjects with potentially confounding comedications. The minor allele (A) frequencies of GATM rs9806699 in the controls (n = 106), mild SIM (n = 324), and severe SIM (n = 285) cases were 0.26, 0.28, and 0.29, respectively (p = 0.447). The unadjusted odds ratio for the A allele for any SIM (mild or severe) was 1.14 (0.82-1.61; p = 0.437), which remained nonsignificant in all models. Our results do not replicate the association between GATM rs9806699 and SIM.

  14. [Risk factors of influenza (H1N1) 2009 hospitalization and effectiveness of pharmaceutical and nonpharmaceutical interventions in its prevention: a case-control study].

    PubMed

    Domínguez, Angela; Alonso, Jordi; Astray, Jenaro; Baricot, Maretva; Cantón, Rafael; Castilla, Jesús; Castro, Ady; Delgado, Miguel; Godoy, Pere; González-Candelas, Fernando; Martín, Vicente; Mayoral, José María; Quintana, José María; Perea, Emilio; Pumarola, Tomás; Soldevila, Nuria; Tamames, Sonia

    2011-01-01

    Potentially useful pharmaceutical measures to limit the impact of pandemic influenza in the community include antiviral drugs (neuraminidase inhibitors) and the influenza and pneumococcal vaccines, as influenza predisposes to bacterial pneumonia caused by Streptococcus pneumoniae. Non-pharmaceutical measures include hand washing and respiratory hygiene. Due to the lack of knowledge of the effectiveness of these measures in a pandemic situation, in September 2009, CIBER de Epidemiología y Salud Pública presented a multicenter case-control study, with controls matched for age, hospital and date of hospitalization, to investigate these aspects in 37 hospitals in 7 Spanish autonomous communities, in response to the call for research projects by the Ministry of Science and Innovation Research Program on Influenza A (H1N1) in Spain. For each confirmed hospitalized case of pandemic influenza, 1 confirmed outpatient case and 3 controls (2 hospitalized and 1 outpatient) were selected. Demographic variables, underlying medical conditions, use of antiviral agents, vaccines received and hygiene habits were collected for all cases and controls. In hospitalized cases, information on antiviral therapy and disease progression was collected. A total of 3750 patients were recruited by October 2010. Data cleansing and the recovery of variables is now underway. The involvement of the Public Health Directorate has been instrumental in adapting the project to the evolution of the pandemic.

  15. Case-control study of ectopic pregnancies in Myanmar: infectious etiological factors.

    PubMed

    Khin-Nwe-Oo; Wah-Wah-Aung; Moe-Thida; Khin-Thet-Wai; Hta-Hta-Yi; Win-Win-Mya

    2011-03-01

    We studied the role of infections in ectopic pregnancy and the different methods of detecting Chlamydia trachomatis infection using serology, cervical and tubal PCR assays, by using a hospital-based, case-control study conducted between November 2007 and September 2009. The sample size was 339 with 113 cases and 226 controls. The cases were women admitted for the management of ectopic pregnancy while the controls were women admitted for spontaneous miscarriage. Both cases and controls were tested for syphilis and chlamydial infection by serology. In addition, cervical samples from controls and both cervical and tubal samples from cases were examined for the presence of chlamydia and gonococcal DNA. Sociodemographic data and past histories were collected using set Proforma. Independent variables for multivariate analysis included previous history of spontaneous abortion, ectopic pregnancy, symptoms of sexully transmitted infections (STI), and use of contraception. Women with a previous history of ectopic pregnancy (adjusted OR 28.3; 95% CI 5.8-138.8; p = 0.01) and a past history of having had symptoms of STI (adjusted OR 11.06; 95% CI 5.45-22.44; p = 0.0005) were significantly more likely to have an ectopic pregnancy than those without such a history. Syphilis serology was positive in 13.3% of ectopic pregnancy cases compared to only 3.5% of controls (crude OR 0.24; 95% CI -0.10-0.58; p = 0.001). From cervical swabs, chlamydia DNA was detected significantly more frequently in cases than controls (8.0% vs 2.2%; crude OR 0.261; 95% CI -0.09-0.80, p = 0.012) but gonorrhea DNA detection rates were not significantly different (3.5% vs 0.9%, crude OR 0.24; 95% CI -0.04-1.35; p = 0.1). Chlamydia was positive in cases only as diagnosed tubal samples for PCR in 17 (15.0%), cervical samples for PCR in 9 (8.0%) and IgM ELISA in 6 (5.3%). Among the three STI tested for in this study, C. trachomatis was the most frequently associated with ectopic pregnancy and was more

  16. Resampling Procedures for Making Inference under Nested Case-control Studies

    PubMed Central

    Cai, Tianxi; Zheng, Yingye

    2013-01-01

    The nested case-control (NCC) design have been widely adopted as a cost-effective solution in many large cohort studies for risk assessment with expensive markers, such as the emerging biologic and genetic markers. To analyze data from NCC studies, conditional logistic regression (Goldstein and Langholz, 1992; Borgan et al., 1995) and maximum likelihood (Scheike and Juul, 2004; Zeng et al., 2006) based methods have been proposed. However, most of these methods either cannot be easily extended beyond the Cox model (Cox, 1972) or require additional modeling assumptions. More generally applicable approaches based on inverse probability weighting (IPW) have been proposed as useful alternatives (Samuelsen, 1997; Chen, 2001; Samuelsen et al., 2007). However, due to the complex correlation structure induced by repeated finite risk set sampling, interval estimation for such IPW estimators remain challenging especially when the estimation involves non-smooth objective functions or when making simultaneous inferences about functions. Standard resampling procedures such as the bootstrap cannot accommodate the correlation and thus are not directly applicable. In this paper, we propose a resampling procedure that can provide valid estimates for the distribution of a broad class of IPW estimators. Simulation results suggest that the proposed procedures perform well in settings when analytical variance estimator is infeasible to derive or gives less optimal performance. The new procedures are illustrated with data from the Framingham Offspring Study to characterize individual level cardiovascular risks over time based on the Framingham risk score, C-reactive protein (CRP) and a genetic risk score. PMID:24436503

  17. Inflammation and endothelium response in epileptic patients: A case-control study

    PubMed Central

    Farhang, Amir; Javanmard, Saghayegh Haghjooy; Mehvari, Jafar; Zare, Mohammad; Saadatnia, Mohammad

    2016-01-01

    Background: Blood brain barrier (BBB) permeability plays an important role in the brain impairments. The barrier is composed of endothelium cells, due to the presence of tight junctions that connect endothelium cells. The failure of BBB function has triggering chronic or acute seizures through brain inflammation and BBB permeability. Seizure induces vasodilation, BBB leakage and up-regulation of vascular cell adhesion molecules which able to bind integrins blood leukocytes. Materials and Methods: In this case-control study we included 40 epileptic patients who were sampled during a seizure as a case group and 20 healthy subjects as a healthy control group. Plasma levels of the inflammation and endothelium markers including intercellular adhesion molecule (ICAM), vascular adhesion molecule (VCAM), interleukin 1 beta (IL-1β) and C-reactive protein (CRP) were measured by enzyme-linked immunosorbent assays (ELISAs). Results: The ICAM and VCAM concentration in the epileptic patients (135.8 ± 5.35) (52.04 ± 4.24) were significantly higher than healthy control group (110.32 ± 5.04) (23.38 ± 3.01) (P < 0.005). IL-1 beta concentration was not significantly different between groups (P = 0.594). However, CRP level was significantly up-regulated in epileptic patients (P < 0.005). Conclusion: Epileptic patients have BBB leakage and dysfunction as the up-regulation of the endothelium cytokines showed. The BBB leakage may be the result of the inflammatory impairment.

  18. Outlining a Population "at Risk" of Parkinson's Disease: Evidence from a Case-Control Study.

    PubMed

    Schirinzi, Tommaso; Martella, Giuseppina; D'Elia, Alessio; Di Lazzaro, Giulia; Imbriani, Paola; Madeo, Graziella; Monaco, Leonardo; Maltese, Marta; Pisani, Antonio

    2016-01-01

    The multifactorial pathogenesis of Parkinson's Disease (PD) requires a careful identification of populations "at risk" of developing the disease. In this case-control study we analyzed a large Italian population, in an attempt to outline general criteria to define a population "at risk" of PD. We enrolled 300 PD patients and 300 controls, gender and age matched, from the same urban geographical area. All subjects were interviewed on demographics, family history of PD, occupational and environmental toxicants exposure, smoking status, and alcohol consumption. A sample of 65 patients and 65 controls also underwent serum dosing of iron, copper, mercury, and manganese by means of Inductively Coupled-Plasma-Mass-Spectrometry (ICP-MS). Positive family history, toxicants exposure, non-current-smoker, and alcohol nonconsumer status occurred as significant risk factors in our population. The number of concurring risk factors overlapping in the same subject impressively increased the overall risk. No significant differences were measured in the metal serum levels. Our findings indicate that combination of three to four concurrent PD-risk factors defines a condition "at risk" of PD. A simple stratification, based on these questionnaires, might be of help in identifying subjects suitable for neuroprotective strategies. PMID:27651975

  19. Time-series microarray data simulation modeled with a case-control label.

    PubMed

    Liu, Y J; Zhang, J Y

    2016-05-12

    With advances in molecular biology, microarray data have become an important resource in the exploration of complex human diseases. Although gene chip technology continues to grow, there are still many barriers to overcome, such as high costs, small sample sizes, complex procedures, poor repeatability, and the dependence on data analysis methods. To avoid these problems, simulation data have a vital role in the study of complex diseases. A simulation method of microarray data is introduced in this study to model the occurrence and development of general diseases. Using classic statistics and control theory, five risk models are proposed. One or more models can be introduced into the baseline simulation dataset with a case-control label. In addition, time-series gene expression data can be generated to model the dynamic evolutionary process of a disease. The prevalence of each model is estimated and disease-associated genes are tested by significance analysis of microarrays. The source code, written in MATLAB, is freely and publicly available at http://sourceforge.net/projects/genesimulation/files/.

  20. Crash involvement of large trucks by configuration: a case-control study.

    PubMed Central

    Stein, H S; Jones, I S

    1988-01-01

    For a two-year period, large truck crashes on the interstate system in Washington State were investigated using a case-control method. For each large truck involved in a crash, three trucks were randomly selected for inspection from the traffic stream at the same time and place as the crash but one week later. The effects of truck and driver characteristics on crashes were assessed by comparing their relative frequency among the crash-involved and comparison sample trucks. Double trailer trucks were consistently overinvolved in crashes by a factor of two to three in both single and multiple vehicle crashes. Single unit trucks pulling trailers also were overinvolved. Doubles also had a higher frequency of jackknifing compared to tractor-trailers. The substantial overinvolvement of doubles in crashes was found regardless of driver age, hours of driving, cargo weight, or type of fleet. Younger drivers, long hours of driving, and operating empty trucks were also associated with higher crash involvement. PMID:3354729

  1. Toxoplasma gondii Infection in Pregnant Women: A Seroprevalence and Case-Control Study in Eastern China.

    PubMed

    Cong, Wei; Dong, Xiao-Yan; Meng, Qing-Feng; Zhou, Na; Wang, Xiang-Yang; Huang, Si-Yang; Zhu, Xing-Quan; Qian, Ai-Dong

    2015-01-01

    Very limited information is available concerning the epidemiology of T. gondii infection in pregnant women in eastern China. Therefore, a case-control study was conducted to estimate the seroprevalence of toxoplasmosis in this population group and to identify risk factors and possible routes of contamination. Serum samples were collected from 965 pregnant women and 965 age-matched nonpregnant control subjects in Qingdao and Weihai between October 2011 and July 2013. These were screened with enzyme linked immunoassays for the presence of anti-Toxoplasma IgG and anti-Toxoplasma IgM antibodies. 147 (15.2%) pregnant women and 167 (17.3%) control subjects were positive for anti-T. gondii IgG antibodies, while 28 (2.9%) pregnant women and 37 (3.8%) controls were positive for anti-T. gondii IgM antibodies (P = 0.256). There was no significant difference between pregnant women and nonpregnant controls with regard to the seroprevalence of either anti-T. gondii IgG or IgM antibodies. Multivariate analysis showed that T. gondii infection was associated with location, cats in home, contact with cats and dogs, and exposure to soil. The results indicated that the seroprevalence of T. gondii infection in pregnant women is high compared to most other regions of China and other East Asian countries with similar climatic conditions. PMID:26539465

  2. Blessed be the Children: A Case-Control Study of Sexual Abusers in the Catholic Church.

    PubMed

    Calkins, Cynthia; Fargo, Jamison; Jeglic, Elizabeth; Terry, Karen

    2015-08-01

    Individuals working in churches and other youth-serving institutions have a unique level of access to children, yet the problem of sexual abuse in institutional settings has received scant research attention. To address this gap, we analyzed data from a large sample of clergy (N = 1,121) and applied a social-ecological model of offending to identify risk factors for sexual abuse perpetration. Using a case-control study design that compared clergy sexual abusers with three control groups of clergy, this study focuses specifically on individual-, relationship-, and community-level factors associated with a higher risk of abuse in professional populations. Findings revealed that clergy sexual abusers tended to have more truncated pre-seminary dating histories, and that their dating and sexual partners were more likely to have been male than female. Self-reported sexual abuse history was associated with a greater likelihood of sexual abuse perpetration among clergy. Clergy abusers tended to be more involved with youth and adolescents in their ministries; however, they were observed to relate less well to youth and adolescents than their clergy counterparts. Given widespread changes in our cultural understanding of abuse as well as more specific changes in the organizational approach to seminary education, these differences underscore the role that youth-serving institutions and society can have in the primary prevention of child sexual abuse. PMID:26294387

  3. Time-series microarray data simulation modeled with a case-control label.

    PubMed

    Liu, Y J; Zhang, J Y

    2016-01-01

    With advances in molecular biology, microarray data have become an important resource in the exploration of complex human diseases. Although gene chip technology continues to grow, there are still many barriers to overcome, such as high costs, small sample sizes, complex procedures, poor repeatability, and the dependence on data analysis methods. To avoid these problems, simulation data have a vital role in the study of complex diseases. A simulation method of microarray data is introduced in this study to model the occurrence and development of general diseases. Using classic statistics and control theory, five risk models are proposed. One or more models can be introduced into the baseline simulation dataset with a case-control label. In addition, time-series gene expression data can be generated to model the dynamic evolutionary process of a disease. The prevalence of each model is estimated and disease-associated genes are tested by significance analysis of microarrays. The source code, written in MATLAB, is freely and publicly available at http://sourceforge.net/projects/genesimulation/files/. PMID:27323009

  4. Caffeine intake and low birth weight: a population-based case-control study.

    PubMed

    Santos, I S; Victora, C G; Huttly, S; Carvalhal, J B

    1998-04-01

    The authors conducted a matched case-control study to investigate the effects of caffeine intake during pregnancy on birth weight. From January to November 1992, in the first 24 hours after delivery, 1,205 mothers (401 cases and 804 controls) were interviewed and their newborns were examined to assess birth weight and gestational age by means of the method of Capurro et al. (J Pediatr 1978;93:120-2). The cases were children with birth weight < 2,500 g and gestational age > or = 28 weeks. Cases and controls were matched for time of birth and hospital of delivery and were recruited from the four maternity hospitals in Pelotas, southern Brazil. Daily maternal caffeine intake during pregnancy for each trimester was estimated. To assess caffeine intake, 10% of the mothers were reinterviewed at their households and samples of reported information on drip coffee and maté (a caffeine-containing drink widely used in South America) were collected and sent to the laboratory for caffeine determination through liquid chromatography. When instant coffee was reported, the weight of powder was measured using a portable scale, and caffeine intake was estimated from a reference table. Caffeine intake from tea, chocolate, soft drinks, and medicines was estimated from a reference table. Analyses were performed by conditional logistic regression. Crude analyses showed no effect of caffeine on low birth weight, preterm births or intrauterine growth retardation. The results did not change after allowing for confounders.

  5. Child pedestrian and bicyclist injuries: results of community surveillance and a case-control study.

    PubMed Central

    Kraus, J. F.; Hooten, E. G.; Brown, K. A.; Peek-Asa, C.; Heye, C.; McArthur, D. L.

    1996-01-01

    OBJECTIVES: To describe the dimensions of childhood pedestrian and bicyclist injuries in Long Beach, California, and to identify risk factors for these injuries. POPULATION: Long Beach residents aged 0-14 years who were involved in an auto versus pedestrian or bicyclist incident that resulted in a hospital visit and/or police response, between 1 September 1988 and 31 August 1990. METHODS: Cases were identified retrospectively using hospital charts, police records, and coroner's reports; demographic, clinical, and situational information were abstracted from the same. A nested case-control study was conducted to examine the street environments where children were injured, and to identify environmental risk factors at these case sites. RESULTS: 288 children comprised the sample population. Midblock dart-outs emerged as the single most common type of incident. Most incidents happened on residential streets, but the risk of injury was greatest on larger boulevards, and tended to cluster by region within the city. Adjusted odds ratios show that case sites had a larger proportion of traffic exceeding posted speed limits, and were also four times more likely to be near a convenience store, gas station, or fast food store than control sites. CONCLUSIONS: The findings of this study suggest three possible routes for the prevention of childhood pedestrian and bicyclist injuries: education, law enforcement, and environmental modification. PMID:9346093

  6. Outlining a Population "at Risk" of Parkinson's Disease: Evidence from a Case-Control Study.

    PubMed

    Schirinzi, Tommaso; Martella, Giuseppina; D'Elia, Alessio; Di Lazzaro, Giulia; Imbriani, Paola; Madeo, Graziella; Monaco, Leonardo; Maltese, Marta; Pisani, Antonio

    2016-01-01

    The multifactorial pathogenesis of Parkinson's Disease (PD) requires a careful identification of populations "at risk" of developing the disease. In this case-control study we analyzed a large Italian population, in an attempt to outline general criteria to define a population "at risk" of PD. We enrolled 300 PD patients and 300 controls, gender and age matched, from the same urban geographical area. All subjects were interviewed on demographics, family history of PD, occupational and environmental toxicants exposure, smoking status, and alcohol consumption. A sample of 65 patients and 65 controls also underwent serum dosing of iron, copper, mercury, and manganese by means of Inductively Coupled-Plasma-Mass-Spectrometry (ICP-MS). Positive family history, toxicants exposure, non-current-smoker, and alcohol nonconsumer status occurred as significant risk factors in our population. The number of concurring risk factors overlapping in the same subject impressively increased the overall risk. No significant differences were measured in the metal serum levels. Our findings indicate that combination of three to four concurrent PD-risk factors defines a condition "at risk" of PD. A simple stratification, based on these questionnaires, might be of help in identifying subjects suitable for neuroprotective strategies.

  7. Inflammation and endothelium response in epileptic patients: A case-control study

    PubMed Central

    Farhang, Amir; Javanmard, Saghayegh Haghjooy; Mehvari, Jafar; Zare, Mohammad; Saadatnia, Mohammad

    2016-01-01

    Background: Blood brain barrier (BBB) permeability plays an important role in the brain impairments. The barrier is composed of endothelium cells, due to the presence of tight junctions that connect endothelium cells. The failure of BBB function has triggering chronic or acute seizures through brain inflammation and BBB permeability. Seizure induces vasodilation, BBB leakage and up-regulation of vascular cell adhesion molecules which able to bind integrins blood leukocytes. Materials and Methods: In this case-control study we included 40 epileptic patients who were sampled during a seizure as a case group and 20 healthy subjects as a healthy control group. Plasma levels of the inflammation and endothelium markers including intercellular adhesion molecule (ICAM), vascular adhesion molecule (VCAM), interleukin 1 beta (IL-1β) and C-reactive protein (CRP) were measured by enzyme-linked immunosorbent assays (ELISAs). Results: The ICAM and VCAM concentration in the epileptic patients (135.8 ± 5.35) (52.04 ± 4.24) were significantly higher than healthy control group (110.32 ± 5.04) (23.38 ± 3.01) (P < 0.005). IL-1 beta concentration was not significantly different between groups (P = 0.594). However, CRP level was significantly up-regulated in epileptic patients (P < 0.005). Conclusion: Epileptic patients have BBB leakage and dysfunction as the up-regulation of the endothelium cytokines showed. The BBB leakage may be the result of the inflammatory impairment. PMID:27656600

  8. A Case-Control Study on the Oxidative Balance of 50% Autologous Serum Eye Drops.

    PubMed

    Gus, Patrícia Ioschpe; Marinho, Diane; Zelanis, Samira; Belló-Klein, Adriane; Locatelli, Claudete; Nicola, Felipe; Kunzler, Ana Laura; Fernandes, Tania Regina Gatelli; Carraro, Cristina Campos; Barbosa, Luciene

    2016-01-01

    Importance. Autologous serum (AS) eye drops are recommended for severe dry eye in patients with ocular surface disease. No description of the antioxidant balance of AS eye drops has been reported in the literature. Objective. This study sought to evaluate the total reactive antioxidant potential (TRAP) and concentration of reactive oxygen species (ROS) in samples of 50% AS eye drops and their correlations with the demographic characteristics and lifestyle habits of patients with ocular surface disease and healthy controls. Design. This was a case-control study with a 3-month follow-up period. Participants. 16 patients with severe dry eye disease of different etiologies and 17 healthy controls matched by age, gender, and race were included. Results. TRAP and ROS were detected at all evaluated times. There were no differences in the mean ROS (p = 0.429) or TRAP (p = 0.475) levels between cases and controls. No statistically significant differences in the concentrations of ROS or TRAPs were found at 0, 15, or 30 days (p for ROS = 0.087 and p for TRAP = 0.93). Neither the demographic characteristics nor the lifestyle habits were correlated with the oxidative balance of the 50% AS eye drops. Conclusions and Relevance. Both fresh and frozen 50% AS eye drops present antioxidant capacities and ROS in an apparently stable balance. Moreover, patients with ocular surface disease and normal controls produce equivalent AS eye drops in terms of oxidative properties. PMID:27635188

  9. A Case-Control Study on the Oxidative Balance of 50% Autologous Serum Eye Drops

    PubMed Central

    Marinho, Diane; Zelanis, Samira; Belló-Klein, Adriane; Locatelli, Claudete; Nicola, Felipe; Kunzler, Ana Laura; Fernandes, Tania Regina Gatelli; Carraro, Cristina Campos; Barbosa, Luciene

    2016-01-01

    Importance. Autologous serum (AS) eye drops are recommended for severe dry eye in patients with ocular surface disease. No description of the antioxidant balance of AS eye drops has been reported in the literature. Objective. This study sought to evaluate the total reactive antioxidant potential (TRAP) and concentration of reactive oxygen species (ROS) in samples of 50% AS eye drops and their correlations with the demographic characteristics and lifestyle habits of patients with ocular surface disease and healthy controls. Design. This was a case-control study with a 3-month follow-up period. Participants. 16 patients with severe dry eye disease of different etiologies and 17 healthy controls matched by age, gender, and race were included. Results. TRAP and ROS were detected at all evaluated times. There were no differences in the mean ROS (p = 0.429) or TRAP (p = 0.475) levels between cases and controls. No statistically significant differences in the concentrations of ROS or TRAPs were found at 0, 15, or 30 days (p for ROS = 0.087 and p for TRAP = 0.93). Neither the demographic characteristics nor the lifestyle habits were correlated with the oxidative balance of the 50% AS eye drops. Conclusions and Relevance. Both fresh and frozen 50% AS eye drops present antioxidant capacities and ROS in an apparently stable balance. Moreover, patients with ocular surface disease and normal controls produce equivalent AS eye drops in terms of oxidative properties. PMID:27635188

  10. Role of Platelet Parameters on Sudden Sensorineural Hearing Loss: A Case-Control Study in Iran.

    PubMed

    Mirvakili, Abbas; Dadgarnia, Mohammad Hossein; Baradaranfar, Mohammad Hossein; Atighechi, Saeid; Zand, Vahid; Ansari, Abdollah

    2016-01-01

    Sudden sensorineural hearing loss (SSNHL) is a common otological disorder characterized by a hearing loss greater than 30 dB over three consecutive frequencies, in less than 72 hours. It has been established that platelet parameters, such as mean platelet volume, are associated with ischemic heart events, whose clinical manifestations are similar to those of SSNHL. Hence, we aimed to determine if the platelet count, mean platelet volume and platelet distribution width are related to the occurrence and severity of sudden sensorineural hearing loss. A case-control prospective study was conducted in a teaching hospital in Iran. One hundred-eight patients with SSNHL and an equal number of healthy, age- and sex-matched controls were enrolled in the study. Peripheral venous blood samples were collected from the subjects, and the platelet count, mean platelet volume and platelet distribution width were measured with an automated blood cell counter. Analysis of the audiometry and hematological test results using SPSS22 software showed no statistical correlation between the platelet parameters and the occurrence of SSNHL, but correlation coefficients showed a significant correlation between PDW and hearing loss severity in patients group. However, further investigation is required to unequivocally establish the absence of correlation between the platelet parameters and occurrence of SSNHL.

  11. Toxoplasma gondii Infection in Pregnant Women: A Seroprevalence and Case-Control Study in Eastern China

    PubMed Central

    Cong, Wei; Dong, Xiao-Yan; Meng, Qing-Feng; Zhou, Na; Wang, Xiang-Yang; Huang, Si-Yang; Zhu, Xing-Quan; Qian, Ai-Dong

    2015-01-01

    Very limited information is available concerning the epidemiology of T. gondii infection in pregnant women in eastern China. Therefore, a case-control study was conducted to estimate the seroprevalence of toxoplasmosis in this population group and to identify risk factors and possible routes of contamination. Serum samples were collected from 965 pregnant women and 965 age-matched nonpregnant control subjects in Qingdao and Weihai between October 2011 and July 2013. These were screened with enzyme linked immunoassays for the presence of anti-Toxoplasma IgG and anti-Toxoplasma IgM antibodies. 147 (15.2%) pregnant women and 167 (17.3%) control subjects were positive for anti-T. gondii IgG antibodies, while 28 (2.9%) pregnant women and 37 (3.8%) controls were positive for anti-T. gondii IgM antibodies (P = 0.256). There was no significant difference between pregnant women and nonpregnant controls with regard to the seroprevalence of either anti-T. gondii IgG or IgM antibodies. Multivariate analysis showed that T. gondii infection was associated with location, cats in home, contact with cats and dogs, and exposure to soil. The results indicated that the seroprevalence of T. gondii infection in pregnant women is high compared to most other regions of China and other East Asian countries with similar climatic conditions. PMID:26539465

  12. Toxoplasma Gondii Infection and Depression: A Case-Control Seroprevalence Study.

    PubMed

    Alvarado-Esquivel, Cosme; Sánchez-Anguiano, Luis Francisco; Hernández-Tinoco, Jesús; Berumen-Segovia, Luis Omar; Torres-Prieto, Yazmin Elizabeth; Estrada-Martínez, Sergio; Pérez-Álamos, Alma Rosa; Ortiz-Jurado, María Nalleli; Molotla-de-León, Gabriel; Beristain-García, Isabel; Rábago-Sánchez, Elizabeth; Liesenfeld, Oliver

    2016-06-24

    We assessed the association of Toxoplasma gondii infection and depression in a sample of psychiatric patients and control subjects without depression. We performed an age- and gender-matched case-control study of 89 patients suffering from depression attended in a public psychiatric hospital in Durango City, Mexico and 356 control subjects without depression from the general population of the same city. Participants were tested for the presence of anti-Toxoplasma IgG and IgM antibodies using enzyme-linked immunoassays. Anti-T. gondii IgG antibodies were found in 11 (12.4%) of the 89 cases and in 22 (6.2%) of the 356 controls (OR = 2.14; 95% CI: 1.00-4.59; P = 0.04). Anti-T. gondii IgM antibodies were found in four (19%) of 21 anti-T. gondii IgG seropositive controls but not in 11 anti-T. gondii IgG seropositive cases (P = 0.27). Patients aged 30 years old and younger had a significantly higher seroprevalence of T. gondii infection than controls of the same age group (P = 0.001). Results of the present study suggest a potential association between T. gondii infection and depression. Furthers studies to confirm our results and to determine the epidemiology of T. gondii in young depressed patients should be conducted. PMID:27429790

  13. A Case-Control Study on the Oxidative Balance of 50% Autologous Serum Eye Drops.

    PubMed

    Gus, Patrícia Ioschpe; Marinho, Diane; Zelanis, Samira; Belló-Klein, Adriane; Locatelli, Claudete; Nicola, Felipe; Kunzler, Ana Laura; Fernandes, Tania Regina Gatelli; Carraro, Cristina Campos; Barbosa, Luciene

    2016-01-01

    Importance. Autologous serum (AS) eye drops are recommended for severe dry eye in patients with ocular surface disease. No description of the antioxidant balance of AS eye drops has been reported in the literature. Objective. This study sought to evaluate the total reactive antioxidant potential (TRAP) and concentration of reactive oxygen species (ROS) in samples of 50% AS eye drops and their correlations with the demographic characteristics and lifestyle habits of patients with ocular surface disease and healthy controls. Design. This was a case-control study with a 3-month follow-up period. Participants. 16 patients with severe dry eye disease of different etiologies and 17 healthy controls matched by age, gender, and race were included. Results. TRAP and ROS were detected at all evaluated times. There were no differences in the mean ROS (p = 0.429) or TRAP (p = 0.475) levels between cases and controls. No statistically significant differences in the concentrations of ROS or TRAPs were found at 0, 15, or 30 days (p for ROS = 0.087 and p for TRAP = 0.93). Neither the demographic characteristics nor the lifestyle habits were correlated with the oxidative balance of the 50% AS eye drops. Conclusions and Relevance. Both fresh and frozen 50% AS eye drops present antioxidant capacities and ROS in an apparently stable balance. Moreover, patients with ocular surface disease and normal controls produce equivalent AS eye drops in terms of oxidative properties.

  14. A case-control study of ultraviolet radiation exposure, vitamin D, and lymphoma risk in adults

    PubMed Central

    Kelly, Jennifer L.; Friedberg, Jonathan W.; Calvi, Laura M.; van Wijngaarden, Edwin; Fisher, Susan G.

    2010-01-01

    Recent research suggests that ultraviolet radiation exposure (UVRE), our major source of vitamin D, is associated with reduced lymphoma risk. Animal and human studies support an association between vitamin D (vitD) insufficiency and increased risk of some malignancies. We conducted a clinic-based case-control study (140 lymphoma cases, 139 controls; 2002–2005, Rochester, NY) to evaluate UVRE and vitD insufficiency in relation to lymphoma risk. Subjects completed a survey and provided a blood sample. We used multivariable logistic regression to estimate lymphoma risk in relation to past (5–10 years prior) UVRE and current vitD insufficiency (determined by serum 25(OH)D). Possible differences in effect by lymphoma subtype were explored, but statistical power was limited. We confirmed the previously reported decrease in lymphoma risk with past UVRE, specifically sunbathing (>once/week versus never); adjusted odds ratio (ORadj), = 0.28, 95% confidence interval (CI): 0.10–0.79. Current vitD insufficiency was not associated with lymphoma risk (ORadj=0.89, 95% CI: 0.47–1.72). However, current sunbathing frequency was correlated with measured serum 25(OH)D values. Therefore, while our data do not support an association with current vitD status, development of accurate methods for past vitD assessment to further investigate its role in the association between past UVRE and lymphoma risk is warranted. PMID:20373010

  15. Chinese Eye Exercises and Myopia Development in School Age Children: A Nested Case-control Study

    PubMed Central

    Kang, Meng-Tian; Li, Shi-Ming; Peng, Xiaoxia; Li, Lei; Ran, Anran; Meng, Bo; Sun, Yunyun; Liu, Luo-Ru; Li, He; Millodot, Michel; Wang, Ningli

    2016-01-01

    Chinese eye exercises have been implemented in China as an intervention for controlling children’s myopia for over 50 years. This nested case-control study investigated Chinese eye exercises and their association with myopia development in junior middle school children. Outcome measures were the onset and progression of myopia over a two-year period. Cases were defined as 1. Myopia onset (cycloplegic spherical equivalent ≤ −0.5 diopter in non-myopic children). 2. Myopia progression (myopia shift of ≥1.0 diopter in those who were myopic at baseline). Two independent investigators assessed the quality of Chinese eye exercises performance at the end of the follow-up period. Of 260 children at baseline (mean age was 12.7 ± 0.5 years), 201 were eligible for this study. There was no association between eye exercises and the risk of myopia-onset (OR = 0.73, 95%CI: 0.24–2.21), nor myopia progression (OR = 0.79, 95%CI: 0.41–1.53). The group who performed high quality exercises had a slightly lower myopia progression of 0.15 D than the children who did not perform the exercise over a period of 2 years. However, the limited sample size, low dosage and performance quality of Chinese eye exercises in children did not result in statistical significance and require further studies. PMID:27329615

  16. Role of Platelet Parameters on Sudden Sensorineural Hearing Loss: A Case-Control Study in Iran

    PubMed Central

    2016-01-01

    Sudden sensorineural hearing loss (SSNHL) is a common otological disorder characterized by a hearing loss greater than 30 dB over three consecutive frequencies, in less than 72 hours. It has been established that platelet parameters, such as mean platelet volume, are associated with ischemic heart events, whose clinical manifestations are similar to those of SSNHL. Hence, we aimed to determine if the platelet count, mean platelet volume and platelet distribution width are related to the occurrence and severity of sudden sensorineural hearing loss. A case-control prospective study was conducted in a teaching hospital in Iran. One hundred-eight patients with SSNHL and an equal number of healthy, age- and sex-matched controls were enrolled in the study. Peripheral venous blood samples were collected from the subjects, and the platelet count, mean platelet volume and platelet distribution width were measured with an automated blood cell counter. Analysis of the audiometry and hematological test results using SPSS22 software showed no statistical correlation between the platelet parameters and the occurrence of SSNHL, but correlation coefficients showed a significant correlation between PDW and hearing loss severity in patients group. However, further investigation is required to unequivocally establish the absence of correlation between the platelet parameters and occurrence of SSNHL. PMID:26829393

  17. Putative periodontopathic bacteria and herpesviruses in pregnant women: a case-control study

    PubMed Central

    Lu, Haixia; Zhu, Ce; Li, Fei; Xu, Wei; Tao, Danying; Feng, Xiping

    2016-01-01

    Little is known about herpesvirus and putative periodontopathic bacteria in maternal chronic periodontitis. The present case-control study aimed to explore the potential relationship between putative periodontopathic bacteria and herpesviruses in maternal chronic periodontitis.Saliva samples were collected from 36 pregnant women with chronic periodontitis (cases) and 36 pregnant women with healthy periodontal status (controls). Six putative periodontopathic bacteria (Porphyromonas gingivalis [Pg], Aggregatibacer actinomycetemcomitans [Aa], Fusobacterium nucleatum [Fn], Prevotella intermedia [Pi], Tannerella forsythia [Tf], and Treponema denticola [Td]) and three herpesviruses (Epstein-Barr virus [EBV], human cytomegalovirus [HCMV], and herpes simplex virus [HSV]) were detected. Socio-demographic data and oral health related behaviors, and salivary estradiol and progesterone levels were also collected. The results showed no significant differences in socio-demographic background, oral health related behaviors, and salivary estradiol and progesterone levels between the two groups (all P > 0.05). The detection rates of included periodontopathic microorganisms were not significantly different between the two groups (all P > 0.05), but the coinfection rate of EBV and Pg was significantly higher in the case group than in the control group (P = 0.028). EBV and Pg coinfection may promote the development of chronic periodontitis among pregnant women. PMID:27301874

  18. Control selection strategies in case-control studies of childhood diseases.

    PubMed

    Ma, Xiaomei; Buffler, Patricia A; Layefsky, Michael; Does, Monique B; Reynolds, Peggy

    2004-05-15

    To address concerns regarding the representativeness of controls in case-control studies, two selection strategies were evaluated in a study of childhood leukemia, which commenced in California in 1995. The authors selected two controls per case: one from among children identified by using computerized birth records and located successfully, the other from a roster of friends; both were matched on demographic factors. Sixty-four birth certificate-friend control pairs were enrolled (n = 128). Additionally, 192 "ideal" controls were selected without tracing from the birth records. Data on parental ages, parental education, mother's reproductive history, and birth weight were obtained from the birth certificates of all 320 subjects. For all variables except birth weight, the differences between birth certificate and ideal controls were smaller than those between friend and ideal controls. None of the differences between birth certificate and ideal controls was significant, whereas two factors were significantly different between friend and ideal controls. These findings suggest that friend controls may be less representative than birth certificate controls. Despite difficulty in tracing and a seemingly low participation rate (49.0% for 560 enrolled birth certificate controls), using birth records to recruit controls appears to provide a representative sample of children and an opportunity to assess the representativeness of controls. PMID:15128601

  19. A Case-Control Study on the Oxidative Balance of 50% Autologous Serum Eye Drops

    PubMed Central

    Marinho, Diane; Zelanis, Samira; Belló-Klein, Adriane; Locatelli, Claudete; Nicola, Felipe; Kunzler, Ana Laura; Fernandes, Tania Regina Gatelli; Carraro, Cristina Campos; Barbosa, Luciene

    2016-01-01

    Importance. Autologous serum (AS) eye drops are recommended for severe dry eye in patients with ocular surface disease. No description of the antioxidant balance of AS eye drops has been reported in the literature. Objective. This study sought to evaluate the total reactive antioxidant potential (TRAP) and concentration of reactive oxygen species (ROS) in samples of 50% AS eye drops and their correlations with the demographic characteristics and lifestyle habits of patients with ocular surface disease and healthy controls. Design. This was a case-control study with a 3-month follow-up period. Participants. 16 patients with severe dry eye disease of different etiologies and 17 healthy controls matched by age, gender, and race were included. Results. TRAP and ROS were detected at all evaluated times. There were no differences in the mean ROS (p = 0.429) or TRAP (p = 0.475) levels between cases and controls. No statistically significant differences in the concentrations of ROS or TRAPs were found at 0, 15, or 30 days (p for ROS = 0.087 and p for TRAP = 0.93). Neither the demographic characteristics nor the lifestyle habits were correlated with the oxidative balance of the 50% AS eye drops. Conclusions and Relevance. Both fresh and frozen 50% AS eye drops present antioxidant capacities and ROS in an apparently stable balance. Moreover, patients with ocular surface disease and normal controls produce equivalent AS eye drops in terms of oxidative properties.

  20. Inverse association between yerba mate consumption and idiopathic Parkinson's disease. A case-control study.

    PubMed

    Gatto, Emilia Mabel; Melcon, Carlos; Parisi, Virginia L; Bartoloni, Leonardo; Gonzalez, Claudio D

    2015-09-15

    Yerba mate tea is a very common beverage in some countries of South America. We conducted a case-control study on an individual basis using hospital records to investigate the association between Parkinson's disease (PD) and yerba mate intake. A case was defined as an age of ≥ 40 years with ≥ 1 year of PD. Each case was individually matched by two controls. Exposure was measured by yerba mate consumption, coffee, tea, and alcohol intake and smoking status. The sample consisted of 223 PD patients (mean age 68 years and mean disease duration 7.3 years) and 406 controls. There was an inverse association between yerba mate "bombilla" consumption and PD (OR 0.64, 95% CI: 0.54-0.76, p=0.00001). A multivariate analysis with a logistic regression adjusted by sex, alcohol intake and smoking provided the following results: yerba mate (OR 0.63, 95% CI: 0.53-0.76), tea (OR 0.60, 95% CI: 0.42-0.86), coffee (OR 0.51, 95% CI: 0.35-0.73). We found an inverse association between yerba mate consumption and PD. These results led us to hypothesize that yerba mate may have a potential protective role in the development of PD.

  1. Bovine Viral Diarrhoea Virus (BVDV) in Dairy Cattle: A Matched Case-Control Study.

    PubMed

    Machado, G; Egocheaga, R M F; Hein, H E; Miranda, I C S; Neto, W S; Almeida, L L; Canal, C W; Stein, M C; Corbellini, L G

    2016-02-01

    Bovine viral diarrhoea virus (BVDV) causes one of the most important diseases of cattle in terms of economic costs and welfare. The aims were to estimate herd prevalence and to investigate the factors associated with antibodies in bulk tank milk (BTM) in dairy herds through a matched case-control study. To estimate herd prevalence, BTM samples were randomly selected (n = 314) from a population (N = 1604). The true prevalence of BVDV was 24.3% (CI 95% = 20.1-29.3%). For the case-control study, BVDV antibody-positive herds (high antibody titres) were classified as cases (n = 21) and matched (n = 63) by milk production with herds presenting low antibody titres (ratio of 1 : 3). Three multivariable models were built: 1) full model, holding all 21 variables, and two models divided according to empirical knowledge and similarity among variables; 2) animal factor model; and 3) biosecurity model. The full model (model 1) identified: age as a culling criteria (OR = 0.10; CI 95% = 0.02-0.39; P < 0.01); farms that provided milk to other industries previously (OR = 4.13; CI 95% = 1.17-14.49; P = 0.02); and isolation paddocks for ill animals (OR = 0.14; CI 95% = 0.01-0.26; P = 0.02). The biosecurity model revealed a significant association with the use of natural mating (OR = 9.03; CI 95% = 2.14-38.03; P < 0.01); isolation paddocks for ill animals (OR = 0.06; CI 95% = 0.05-0.83; P = 0.03); years providing milk for the same industry (OR = 0.94; CI 95% = 0.91-0.97; P = 0.02); and direct contact over fences among cattle of neighbouring farms (OR = 5.78; CI 95% = 1.41-23.67; P = 0.04). We recommend the application of grouping predictors as a good choice for model building because it could lead to a better understanding of disease-exposure associations.

  2. A molecular epidemiology case control study on pleural malignant mesothelioma.

    PubMed

    Bolognesi, Claudia; Martini, Fernanda; Tognon, Mauro; Filiberti, Rosa; Neri, Monica; Perrone, Emanuela; Landini, Eleonora; Canessa, Paolo A; Ivaldi, Gian Paolo; Betta, Pietro; Mutti, Luciano; Puntoni, Riccardo

    2005-07-01

    Pleural malignant mesothelioma is an uncommon neoplasm usually associated with asbestos exposure. The increasing incidence of malignant mesothelioma cases involving individuals with low levels of asbestos exposure suggests a complex carcinogenetic process with the involvement of other cofactors. Cytogenetic studies revealed the complexity of the genetic changes involved in this neoplasm reflecting the accumulation of genomic damage. One of the most used methodologies for assessing genomic damage is the cytokinesis-blocked micronucleus test applied in peripheral blood lymphocytes (PBL). This approach allows the detection of chromosomal alterations expressed in binucleated cells after nuclear division in vitro. This marker could provide a tool for assessing genetically determined constitutional differences in chromosomal instability. A biomonitoring study was carried out to evaluate the micronuclei frequency in PBLs of patients with pleural malignant mesothelioma with respect to lung cancer, healthy, and risk controls as a marker of cancer susceptibility in correlation with the presence of SV40. A significant increased micronuclei frequency was observed in patients with malignant mesothelioma in comparison with all the other groups, the mean micronuclei frequency was double in patients with malignant mesothelioma compared with healthy controls, risk controls, and patients with lung adenocarcinoma (median 11.4 binucleated cells with micronuclei/1,000 binucleated cells versus 6.2, 6.1, and 5.1, respectively). Our data indicate that human T lymphocyte samples carry DNA sequences coding for SV40 large T antigen at low prevalence, both in cancer cases and controls. Evidence of cytogenetic damage revealed as micronuclei frequency in mesothelioma cancer patients could be related to exogenous and endogenous cofactors besides asbestos exposure.

  3. HIV and Child Mental Health: A Case-Control Study in Rwanda

    PubMed Central

    Scorza, Pamela; Kanyanganzi, Frederick; Fawzi, Mary C. Smith; Sezibera, Vincent; Cyamatare, Felix; Beardslee, William; Stulac, Sara; Bizimana, Justin I.; Stevenson, Anne; Kayiteshonga, Yvonne

    2014-01-01

    BACKGROUND: The global HIV/AIDS response has advanced in addressing the health and well-being of HIV-positive children. Although attention has been paid to children orphaned by parental AIDS, children who live with HIV-positive caregivers have received less attention. This study compares mental health problems and risk and protective factors in HIV-positive, HIV-affected (due to caregiver HIV), and HIV-unaffected children in Rwanda. METHODS: A case-control design assessed mental health, risk, and protective factors among 683 children aged 10 to 17 years at different levels of HIV exposure. A stratified random sampling strategy based on electronic medical records identified all known HIV-positive children in this age range in 2 districts in Rwanda. Lists of all same-age children in villages with an HIV-positive child were then collected and split by HIV status (HIV-positive, HIV-affected, and HIV-unaffected). One child was randomly sampled from the latter 2 groups to compare with each HIV-positive child per village. RESULTS: HIV-affected and HIV-positive children demonstrated higher levels of depression, anxiety, conduct problems, and functional impairment compared with HIV-unaffected children. HIV-affected children had significantly higher odds of depression (1.68: 95% confidence interval [CI] 1.15–2.44), anxiety (1.77: 95% CI 1.14–2.75), and conduct problems (1.59: 95% CI 1.04–2.45) compared with HIV-unaffected children, and rates of these mental health conditions were similar to HIV-positive children. These results remained significant after controlling for contextual variables. CONCLUSIONS: The mental health of HIV-affected children requires policy and programmatic responses comparable to HIV-positive children. PMID:25049342

  4. Case-control comparison of bacterial and protozoan microorganisms associated with gastroenteritis: application of molecular detection.

    PubMed

    Bruijnesteijn van Coppenraet, L E S; Dullaert-de Boer, M; Ruijs, G J H M; van der Reijden, W A; van der Zanden, A G M; Weel, J F L; Schuurs, T A

    2015-06-01

    The introduction of molecular detection of infectious organisms has led to increased numbers of positive findings, as observed for pathogens causing gastroenteritis (GE). However, because little is known about the prevalence of these pathogens in the healthy asymptomatic population, the clinical value of these additional findings is unclear. A case-control study was carried out in a population of patients served by general practitioners in the Netherlands. A total of 2710 fecal samples from case and matched control subjects were subjected to multiplex real-time PCR for the 11 most common bacterial and four protozoal causes of GE. Of 1515 case samples, 818 (54%) were positive for one or more target organisms. A total of 49% of the controls were positive. Higher positivity rates in cases compared to controls were observed for Campylobacter spp., Salmonella spp., Clostridium difficile, enteroinvasive Escherichia coli/Shigella spp., enterotoxigenic E. coli, enteroaggregative E. coli, atypical enteropathogenic E. coli (EPEC), Cryptosporidium parvum/hominis, and Giardia lamblia. However, Dientamoeba fragilis and Shiga-like toxigenic E. coli were detected significantly less frequent in cases than in controls, while no difference in prevalence was found for typical EPEC and enterohemorrhagic E. coli. The association between the presence of microorganisms and GE was the weakest in children aged 0 to 5 years. Higher relative loads in cases further support causality. This was seen for Campylobacter spp., Salmonella spp., enterotoxigenic E. coli, and C. parvum/hominis, and for certain age categories of those infected with C. difficile, enteroaggregative E. coli, and atypical EPEC. For D. fragilis and Shiga-like toxigenic E. coli/enterohemorrhagic E. coli, pathogen loads were lower in cases. Application of molecular diagnostics in GE is rapid, sensitive and specific, but results should be interpreted with care, using clinical and additional background information.

  5. Multi-Center Traffic Management Advisor Operational Field Test Results

    NASA Technical Reports Server (NTRS)

    Farley, Todd; Landry, Steven J.; Hoang, Ty; Nickelson, Monicarol; Levin, Kerry M.; Rowe, Dennis W.

    2005-01-01

    The Multi-Center Traffic Management Advisor (McTMA) is a research prototype system which seeks to bring time-based metering into the mainstream of air traffic control (ATC) operations. Time-based metering is an efficient alternative to traditional air traffic management techniques such as distance-based spacing (miles-in-trail spacing) and managed arrival reservoirs (airborne holding). While time-based metering has demonstrated significant benefit in terms of arrival throughput and arrival delay, its use to date has been limited to arrival operations at just nine airports nationally. Wide-scale adoption of time-based metering has been hampered, in part, by the limited scalability of metering automation. In order to realize the full spectrum of efficiency benefits possible with time-based metering, a much more modular, scalable time-based metering capability is required. With its distributed metering architecture, multi-center TMA offers such a capability.

  6. A pragmatic discussion on establishing a multicenter digital imaging network.

    PubMed

    Ingeholm, Mary Lou; Levine, Betty A; Fatemi, Seyed Ali; Moser, And Hugo W

    2002-01-01

    Multicenter clinical trials for therapy evaluation of rare diseases are necessary. A digital imaging network improves the ability to share information between collaborating institutions for adrenoleukodystrophy. The DICOM 3.0 standard is used to move images over the Internet from contributing sites to the central clinical database and on to the reviewing physicians' workstations. Patient confidentiality and data integrity are ensured during transmission using virtual private network technology. Fifteen sites are participating in the network. Of these sites, 6 use the proposed protocol. The other 9 sites have either security policy issues or technical considerations that dictate alternative protocols. Network infrastructure, Internet access, image management practices, and security policies vary significantly between sites. Successful implementation of a multicenter digital imaging network requires flexibility in the implementation of network connectivity. Flexibility increases participation as well as complexity of the network. PMID:12105723

  7. Phases of non-extremal multi-centered bound states

    NASA Astrophysics Data System (ADS)

    Chowdhury, Borun D.; Mayerson, Daniel R.; Vercnocke, Bert

    2013-12-01

    We investigate the phase space of multi-centered near-extremal configurations previously studied in arXiv:1108.5821 [1] and arXiv:1110.5641 [2] in the probe limit. We confirm that in general the energetically favored ground state of the multi-center potential, which can be a single or multi-center configuration, has the most entropy and is thus thermodynamically stable. However, we find the surprising result that for a subset of configurations, even though a single center black hole seems to be energetically favored, it is entropically not allowed (the resulting black hole would violate cosmic censorship). This disproves classical intuition that everything would just fall into the black hole if energetically favored. Along the way we highlight a shortcoming in the literature regarding the computation of the angular momentum coming from electromagnetic interaction in the probe limit and rectify it. We also demonstrate that static supertubes can exist inside ergoregions where ordinary point particles would be frame dragged.

  8. An updated review of case-control studies of lung cancer and indoor radon-Is indoor radon the risk factor for lung cancer?

    PubMed

    Sheen, Seungsoo; Lee, Keu Sung; Chung, Wou Young; Nam, Saeil; Kang, Dae Ryong

    2016-01-01

    Lung cancer is a leading cause of cancer-related death in the world. Smoking is definitely the most important risk factor for lung cancer. Radon ((222)Rn) is a natural gas produced from radium ((226)Ra) in the decay series of uranium ((238)U). Radon exposure is the second most common cause of lung cancer and the first risk factor for lung cancer in never-smokers. Case-control studies have provided epidemiological evidence of the causative relationship between indoor radon exposure and lung cancer. Twenty-four case-control study papers were found by our search strategy from the PubMed database. Among them, seven studies showed that indoor radon has a statistically significant association with lung cancer. The studies performed in radon-prone areas showed a more positive association between radon and lung cancer. Reviewed papers had inconsistent results on the dose-response relationship between indoor radon and lung cancer risk. Further refined case-control studies will be required to evaluate the relationship between radon and lung cancer. Sufficient study sample size, proper interview methods, valid and precise indoor radon measurement, wide range of indoor radon, and appropriate control of confounders such as smoking status should be considered in further case-control studies.

  9. An updated review of case-control studies of lung cancer and indoor radon-Is indoor radon the risk factor for lung cancer?

    PubMed

    Sheen, Seungsoo; Lee, Keu Sung; Chung, Wou Young; Nam, Saeil; Kang, Dae Ryong

    2016-01-01

    Lung cancer is a leading cause of cancer-related death in the world. Smoking is definitely the most important risk factor for lung cancer. Radon ((222)Rn) is a natural gas produced from radium ((226)Ra) in the decay series of uranium ((238)U). Radon exposure is the second most common cause of lung cancer and the first risk factor for lung cancer in never-smokers. Case-control studies have provided epidemiological evidence of the causative relationship between indoor radon exposure and lung cancer. Twenty-four case-control study papers were found by our search strategy from the PubMed database. Among them, seven studies showed that indoor radon has a statistically significant association with lung cancer. The studies performed in radon-prone areas showed a more positive association between radon and lung cancer. Reviewed papers had inconsistent results on the dose-response relationship between indoor radon and lung cancer risk. Further refined case-control studies will be required to evaluate the relationship between radon and lung cancer. Sufficient study sample size, proper interview methods, valid and precise indoor radon measurement, wide range of indoor radon, and appropriate control of confounders such as smoking status should be considered in further case-control studies. PMID:26949535

  10. A Multicenter Performance Evaluation of a Blood Glucose Monitoring System in 21 Leading Hospitals in Spain

    PubMed Central

    Bedini, José Luis; Wallace, Jane F.; Petruschke, Thorsten; Pardo, Scott

    2015-01-01

    Background: Self-monitoring of blood glucose is crucial for the effective self-management of diabetes. The present study evaluated the accuracy of the Contour® XT blood glucose monitoring system (BGMS) compared to the reference method in a large multicenter study under routine lab conditions at each hospital site. Methods: This study was conducted at 21 leading hospitals in Spain using leftover whole blood samples (n = 2100). Samples were tested with the BGMS using 1 commercial strip lot and the local laboratory hexokinase method. BGMS accuracy was assessed and results were compared to ISO 15197:2013 accuracy limit criteria and by using mean absolute relative difference analysis (MARD), consensus (Parkes) error grid (CEG), and surveillance error grid analyses (SEG). Results: Pooled analysis of 2100 measurements from all sites showed that 99.43% of the BGMS results were within the ranges accepted by the accuracy limit criteria. The overall MARD was 3.85%. MARD was 4.47% for glucose concentrations < 70 mg/dL and 3.81% for concentrations of 70-300 mg/dL. In CEG, most results (99.8%) were within zone A (“no effect on clinical action”); the remaining ones (0.2%) were in zone B (“little to no effect on clinical action”). The SEG analysis showed that most of the results (98.4%) were in the “no risk” zone, with the remaining results in the “slight, lower” risk zone. Conclusions: This is the largest multicenter study of Contour XT BGMS to date, and shows that this BGMS meets the ISO 15197:2013 accuracy limit criteria under local routine conditions in 21 leading Spanish hospitals. PMID:26253142

  11. A Case-Control Study of the Role of Human Papillomavirus in Oesophageal Squamous Cell Carcinoma in Australia

    PubMed Central

    Liyanage, Surabhi S.; Malik, Aisha; Garland, Suzanne M.; Tabrizi, Sepehr N.; Rahman, Bayzidur; Barbour, Andrew P.; Crowe, Philip J.; MacIntyre, C. Raina

    2014-01-01

    Objective. We investigate the prevalence of human papillomavirus (HPV) in oesophageal squamous cell carcinoma (OSCC) tissues compared to oesophageal tissue from healthy controls, in an Australian cohort. Methods. We conducted a hospital-based case-control study of 99 patients with OSCC and 100 healthy controls to examine the presence of HPV DNA. Paraffin tissues were tested using the PapType high-risk HPV detection and genotyping kit and with INNO-LiPA HPV Genotyping Extra. The biopsy samples were tested for HPV using a PCR-ELISA method based on the L1 consensus primer set PGMY09-PGMY11. Results. HPV DNA of the oncogenic genotype 16 was detected in 1/99 case specimens, a rate of 1010 per 100,000 (95% CI: 30–5500). All control specimens were negative for HPV. Significantly higher rates of smoking, other aerodigestive cancers, and mortality were seen among cases than controls. A pooled analysis of this study and the only other Australian case-control study found that 9/321 cases and 0/155 controls were positive for HPV. The pooled odds ratio for HPV being a risk factor for OSCC was 9.35 (95% CI: 0.47–190.33). Conclusion. Our results suggest that in this multifactorial cancer HPV may be an additional risk factor; although a larger, better powered study is needed. PMID:24872815

  12. Association between Estrogen Receptor Alpha Gene Polymorphisms and Susceptibility to Idiopathic Scoliosis in Bulgarian Patients: A Case-Control Study

    PubMed Central

    Nikolova, Svetla; Yablanski, Vasil; Vlaev, Evgeni; Stokov, Luben; Savov, Alexey; Kremensky, Ivo

    2015-01-01

    BACKGROUND: The current consensus on idiopathic scoliosis maintains that it has a multifactorial etiology with genetic predisposing factors. AIM: Estrogen receptor alpha gene has been considered as candidate gene of idiopathic scoliosis. MATERIAL AND METHODS: We conducted a case-control study of Bulgarian population samples (eighty patients with idiopathic scoliosis and one hundred-sixty healthy unrelated gender-matched controls) trying to investigate the association between common genetic polymorphisms of estrogen receptor alpha and the susceptibility to idiopathic scoliosis. Molecular detection of the restriction polymorphisms XbaI and PvuII was performed by polymerase chain reaction following by restriction fragment length polymorphism. The statistical analysis was performed by Pearson’s chi-squared test. RESULTS: Our case-control study showed statistically significant association between the PvuII polymorphism and susceptibility to idiopathic scoliosis and curve progression. No genotype or allele of XbaI polymorphism was found to be correlated with the onset or severity of the disease. CONCLUSIONS: The identification of molecular markers with diagnostic and prognostic value could be useful for early detection of children at risk for the development of scoliosis and for prognosis of the risk for a rapid deformity progression. That would facilitate the therapy decisions and early stage treatment of the patient with the least invasive procedures. PMID:27275235

  13. Dairy Consumption and Risk of Stroke: A Case-control Study

    PubMed Central

    Boroujeni, Hossein Khosravi; Saadatnia, Mohammad; Shakeri, Forough; Keshteli, Ammar Hassanzadeh; Saneei, Parvane; Esmaillzadeh, Ahmad

    2016-01-01

    Background: It remains controversial if dairy product intake is associated with risk of stroke. Limited information is available from Middle East countries in this regard. This case-control study was conducted to assess the relationship between dairy consumption and risk of stroke in Iranian adults. Methods: In this study, 195 stroke patients (recognized based on clinical findings and computed tomography scan) hospitalized in neurology ward of Alzahra University Hospital were enrolled. Controls (n = 195) were selected with convenience nonrandom sampling procedure from other wards of this hospital. A validated food frequency questionnaire was used to assess participants’ usual dietary intakes. Data on other variables were collected by the use of questionnaires. Results: Patients with stroke were older (P < 0.001), had lower weight and body mass index (P < 0.05) and were more likely to be male (P < 0.05) and less likely to be obese (P < 0.001). After adjustment for age, sex and total energy intake, Individuals with the highest consumption of low-fat dairy had a significantly decreased risk of stroke (odds ratio [OR]: 0.58; 95% of confidence interval [CI]: 0.34–0.99), while those with the highest intake of high-fat dairy had a 2-fold increased risk of stroke. The association between high-fat dairy consumption and stroke even persisted after additional adjustments for physical activity, smoking and dietary variables (OR: 2.02; 95% CI: 1.02–4.02); but the association between low-fat dairy intake and stroke disappeared after these adjustments (OR: 0.84; 95% CI: 0.44–1.58). Conclusions: We found a significant positive association between high-fat dairy consumption and risk of stroke. Further prospective studies are required to confirm this finding. PMID:26941903

  14. Case-control study of the PERIOD3 clock gene length polymorphism and colorectal adenoma formation.

    PubMed

    Alexander, Melannie; Burch, James B; Steck, Susan E; Chen, Chin-Fu; Hurley, Thomas G; Cavicchia, Philip; Ray, Meredith; Shivappa, Nitin; Guess, Jaclyn; Zhang, Hongmei; Youngstedt, Shawn D; Creek, Kim E; Lloyd, Stephen; Yang, Xiaoming; Hébert, James R

    2015-02-01

    Clock genes are expressed in a self-perpetuating, circadian pattern in virtually every tissue including the human gastrointestinal tract. They coordinate cellular processes critical for tumor development, including cell proliferation, DNA damage response and apoptosis. Circadian rhythm disturbances have been associated with an increased risk for colon cancer and other cancers. This mechanism has not been elucidated, yet may involve dysregulation of the 'period' (PER) clock genes, which have tumor suppressor properties. A variable number tandem repeat (VNTR) in the PERIOD3 (PER3) gene has been associated with sleep disorders, differences in diurnal hormone secretion, and increased premenopausal breast cancer risk. Susceptibility related to PER3 has not been examined in conjunction with adenomatous polyps. This exploratory case-control study was the first to test the hypothesis that the 5-repeat PER3 VNTR sequence is associated with increased odds of adenoma formation. Information on demographics, medical history, occupation and lifestyle was collected prior to colonoscopy. Cases (n=49) were individuals with at least one histopathologically confirmed adenoma. Controls (n=97) included patients with normal findings or hyperplastic polyps not requiring enhanced surveillance. Unconditional multiple logistic regression was used to calculate odds ratios (ORs) with 95% confidence intervals (CIs), after adjusting for potential confounding. Adenomas were detected in 34% of participants. Cases were more likely to possess the 5-repeat PER3 genotype relative to controls (4/5 OR, 2.1; 95% CI, 0.9-4.8; 5/5 OR, 5.1; 95% CI, 1.4-18.1; 4/5+5/5 OR, 2.5; 95% CI, 1.7-5.4). Examination of the Oncomine microarray database indicated lower PERIOD gene expression in adenomas relative to adjacent normal tissue. Results suggest a need for follow-up in a larger sample.

  15. Antipsychotic Medications and Risk of Acute Coronary Syndrome in Schizophrenia: A Nested Case-Control Study

    PubMed Central

    Liu, Hsing-Cheng; Yang, Shu-Yu; Liao, Ya-Tang; Chen, Chiao-Chicy; Kuo, Chian-Jue

    2016-01-01

    Background This study assessed the risk of developing acute coronary syndrome requiring hospitalization in association with the use of certain antipsychotic medications in schizophrenia patients. Methods A nationwide cohort of 31,177 inpatients with schizophrenia between the ages of 18 and 65 years whose records were enrolled in the National Health Insurance Research Database in Taiwan from 2000 to 2008 and were studied after encrypting the identifications. Cases (n = 147) were patients with subsequent acute coronary syndrome requiring hospitalization after their first psychiatric admission. Based on a nested case-control design, each case was matched with 20 controls for age, sex and the year of first psychiatric admission using risk-set sampling. The effects of antipsychotic agents on the development of acute coronary syndrome were assessed using multiple conditional logistic regression and sensitivity analyses to confirm any association. Results We found that current use of aripiprazole (adjusted risk ratio [RR] = 3.68, 95% CI: 1.27–10.64, p<0.05) and chlorpromazine (adjusted RR = 2.96, 95% CI: 1.40–6.24, p<0.001) were associated with a dose-dependent increase in the risk of developing acute coronary syndrome. Although haloperidol was associated with an increased risk (adjusted RR = 2.03, 95% CI: 1.20–3.44, p<0.01), there was no clear dose-dependent relationship. These three antipsychotic agents were also associated with an increased risk in the first 30 days of use, and the risk decreased as the duration of therapy increased. Sensitivity analyses using propensity score-adjusted modeling showed that the results were similar to those of multiple regression analysis. Conclusions Patients with schizophrenia who received aripiprazole, chlorpromazine, or haloperidol could have a potentially elevated risk of developing acute coronary syndrome, particularly at the start of therapy. PMID:27657540

  16. Recent Food Shortage Is Associated with Leprosy Disease in Bangladesh: A Case-Control Study

    PubMed Central

    Feenstra, Sabiena G.; Nahar, Quamrun; Pahan, David; Oskam, Linda; Richardus, Jan Hendrik

    2011-01-01

    Background Leprosy is remaining prevalent in the poorest areas of the world. Intensive control programmes with multidrug therapy (MDT) reduced the number of registered cases in these areas, but transmission of Mycobacterium leprae continues in most endemic countries. Socio-economic circumstances are considered to be a major determinant, but uncertainty exists regarding the association between leprosy and poverty. We assessed the association between different socio-economic factors and the risk of acquiring clinical signs of leprosy. Methods and Findings We performed a case-control study in two leprosy endemic districts in northwest Bangladesh. Using interviews with structured questionnaires we compared the socio-economic circumstances of recently diagnosed leprosy patients with a control population from a random cluster sample in the same area. Logistic regression was used to compare cases and controls for their wealth score as calculated with an asset index and other socio-economic factors. The study included 90 patients and 199 controls. A recent period of food shortage and not poverty per se was identified as the only socio-economic factor significantly associated with clinical manifestation of leprosy disease (OR 1.79 (1.06–3.02); p = 0.030). A decreasing trend in leprosy prevalence with an increasing socio-economic status as measured with an asset index is apparent, but not statistically significant (test for a trend: OR 0.85 (0.71–1.02); p = 0.083). Conclusions Recent food shortage is an important poverty related predictor for the clinical manifestation of leprosy disease. Food shortage is seasonal and poverty related in northwest Bangladesh. Targeted nutritional support for high risk groups should be included in leprosy control programmes in endemic areas to reduce risk of disease. PMID:21572979

  17. Risk Factor of Preterm Labor in the West of Iran: A Case-Control Study

    PubMed Central

    DERAKHSHI, Bahareh; ESMAILNASAB, Nader; GHADERI, Ebrahim; HEMMATPOUR, Siroos

    2014-01-01

    Abstract Background Prematurity is the most common cause of neonatal death. Risk factors of premature birth can be related with ethnicity and genetic. There is no comprehensive high sample size study in Kurdish ethnicity to determine risk factors related to prematurity. This study evaluated risk factors of preterm labor in Kurdish ethnicity. Methods This case-control study was conducted in 200 preterm infants (case group) and 400 term infants (control group), in Besat Hospital, Sanandaj, Iran, in the year 2012. Data was analyzed using SPSS software and analysis was performed by Chi-square, Mann-Whitney and logistic regression tests. Results In univariate analysis, mother’s own prematurity, history of previous preterm labor, prematurity in the first-degree family members, history of dead children, premature rupture of membranes, multiple pregnancies, overt diabetes, chronic hypertension, preeclampsia and eclampsia, infertility and cervical incompetence had significant relation-ship with preterm labor. However, multivariate analysis results showed that abnormal amniotic fluid, premature rupture of membranes, double and multiple pregnancies, chronic hypertension, family history of premature birth, mothers age over 35 years, and cervical incompetence (P<0.05) had significant relationship with the premature birth. Conclusion Screening of newborns at risk of preterm labor could be achieved by these risk factors: family history of prematurity, mother’s own history of prematurity and previous preterm labor, history of previous neonatal death, decreased amniotic fluid, multiple pregnancies, overt diabetes, hypertension, preeclampsia, infertility and cervical incompetence, however some of these factors are not the direct cause of prematurity. Our study suggests genetic’ s role in preterm labor. PMID:26005661

  18. A case-control study of diet and lung cancer in northeast China.

    PubMed

    Hu, J; Johnson, K C; Mao, Y; Xu, T; Lin, Q; Wang, C; Zhao, F; Wang, G; Chen, Y; Yang, Y

    1997-06-11

    A case-control study involving interviews with 227 lung-cancer cases and 227 matched hospital controls was conducted in Heilongjiang Province in northeast China to examine the influence of dietary factors on the risk of developing lung cancer. Lung-cancer cases were all incident cases judged to be suitable candidates for tumor removal by surgery. Controls were selected among hospitalized patients with non-neoplastic and non-lung disease. The overall male lung-cancer risks associated with cigarette smoking were similar to those reported in other Chinese studies but quite low compared to risks in Western countries. However, the subjects in this study were relatively young (average age 53.2), had started to smoke on average at a relatively old age (21.3 years), and only smoked an average of 18.7 cigarettes per day. Lung-cancer risk was not strongly associated with any of the nutrients examined, when all cases were compared to all controls. However, the data were suggestive of differences in the relationship of diet to risk among smokers and non-smokers. Cautious interpretation is required because of the wide confidence intervals due to limited sample size. Among the smokers, only higher beta-carotene was associated with estimates suggesting a lowered risk. Among non-smokers, the evidence suggested that increased vegetable consumption might reduce risk, consumption of any fruit might reduce risk but beta-carotene was unrelated to risk. The differences observed in the relationship of diet to lung-cancer risk between Chinese smokers and non-smokers warrant further study.

  19. A nested case-control study of methemoglobinemia risk factors in children of Transylvania, Romania.

    PubMed Central

    Zeman, Catherine L; Kross, Burton; Vlad, Marianna

    2002-01-01

    In this nested case-control study, we investigated the risk factors for methemoglobinemia (MHG) in 71 children in the Transylvania region of Romania. This study was unique in that the exposures for cases and controls were calculated as continuous values and were reported in milligrams per kilogram per day of nitrate/nitrite based on careful dietary reconstruction and environmental sampling. This procedure allowed us to compare point estimates of nitrate/nitrite exposure with other continuous, categoric, and ranked risk factors such as the presence or absence of diarrheal disease, reported severity of diarrheal disease, the use of vitamin supplements, the presence, absence, and/or duration of breast-feeding, and whether or not first-generation relatives experienced MHG. Analysis of these factors and exposure levels using both univariate and multivariate whole-model tests was performed to understand the relative significance of risk factors at varying levels of exposure to the development of MHG. Univariate and multifactorial analysis of risk factors for MHG underscored that, for this population, MHG is most strongly associated with nitrate/nitrite exposure through the dietary route (p = 0.0318), via feeding of formula and tea made with water containing high levels of nitrates, and that breast-feeding protects infants younger than 6 months of age (p = 0.0244). Our findings also raise questions about the role of diarrheal disease in the development of MHG, as likelihood ratios (likelihood 4.323, p = 0.0376) and multifactorial analysis indicated a significant role for diarrheal disease for some individuals. PMID:12153765

  20. A case-control study of the congenital hypothyroidism and dysmaturity syndrome of foals.

    PubMed Central

    Allen, A L; Townsend, H G; Doige, C E; Fretz, P B

    1996-01-01

    A case-control study was conducted to identify risk factors for the congenital hypothyroidism and dysmaturity syndrome of foals. A questionnaire was used during personal interviews of foal owners and farm managers to collect information on animal signalment, farm environment, and mare management. Information on 39 foals with the congenital hypothyroidism and dysmaturity syndrome were compared with 39 control foals. Foals with the syndrome had a significantly (P < 0.0001) longer gestation (357.6 d) than control foals (338.9 d). Pregnant mares that were fed greenfeed, did not receive any supplemental mineral, left their "home farm" during gestation, or grazed irrigated pasture had 13.1 (P = 0.0068), 5.6 (P = 0.0472), 4.3 (P = 0.0076), and approximately 15.3 (P = 0.0245), respectively, greater odds of producing an affected foal than mares not experiencing these events. Greenfeed often contains high levels of nitrate (NO3-), which is known to impair thyroid gland function. In light of this, forage samples from participating farms were analyzed for nitrate levels. The odds of one or more congenitally hypothyroid and dysmature foals being born on a farm feeding forage with at least a trace of nitrate was 8.0 times greater (P = 0.0873) than the odds of the disease occurring on a farm that fed forage free of nitrate. Further, the odds of a mare producing an affected foal when fed forage containing at least a trace of nitrate were 5.9 times greater (P = 0.0007) than those of a mare fed nitrate free forage. This study suggests that congenital hypothyroidism and dysmaturity syndrome in foals may be the result of diets that contain nitrate or that are low in iodine being fed to pregnant mares. PMID:8689594

  1. Are family variables associated with ADHD, inattentive type? A case-control study in schools.

    PubMed

    Pheula, Gabriel Ferreira; Rohde, Luis Augusto; Schmitz, Marcelo

    2011-03-01

    Attention-deficit/hyperactivity disorder (ADHD) seems to be associated with significant psychosocial adversity. However, few studies assessed the role of environmental, social and interpersonal factors specifically in ADHD, inattentive type (ADHD-I). Thus, this study aims to investigate whether family environment risk factors are associated with ADHD-I. In a case-control study, we assessed a non-referred sample of 100 children and adolescents with ADHD-I and 100 non-ADHD controls (6-18 years old). They were systematically evaluated through structured diagnostic interviews. The following family adversity measures were used: Rutter's family adversity index (marital discord, low social class, large family size, paternal criminality, maternal mental disorder), Family Environment Scale (FES) (subscores of cohesion, expressiveness and conflict) and Family Relationship Index (FRI) (based on the subscores above). After adjusting for confounding factors (social phobia and maternal history of ADHD), the odds ratio (OR) for ADHD-I increased as the number of Rutter's indicators increased. Families of children with lower FES cohesion subscores presented higher OR for ADHD-I (OR 1.24; 95% confidence interval 1.05-1.45). Lower levels of FRI, a general index of family relationship, were also related to higher risk of ADHD-I (OR 1.11; 95% confidence interval 1.03-1.21). Our findings suggest that family adversity (in general), low family cohesion and low FRI (in particular) are associated with an increase in the risk for ADHD-I. However, the cross-sectional nature of the study limits our ability to infer causality.

  2. Leptospira Exposure and Waste Pickers: A Case-Control Seroprevalence Study in Durango, Mexico

    PubMed Central

    Alvarado-Esquivel, Cosme; Hernandez-Tinoco, Jesus; Sanchez-Anguiano, Luis Francisco; Ramos-Nevarez, Agar; Cerrillo-Soto, Sandra Margarita; Guido-Arreola, Carlos Alberto

    2015-01-01

    Background Infection with Leptospira may occur by contact with Leptospira-infected animals. Waste pickers are in contact with rodents and dogs while picking in the garbage. Whether waste pickers are at risk for Leptospira infection is largely unknown. This study was aimed to determine the association of Leptospira IgG seroprevalence with the occupation of waste picking, and to determine the epidemiological characteristics of the waste pickers with Leptospira exposure. Methods Through a case-control study, we determined the seroprevalence of anti-Leptospira IgG antibodies in 90 waste pickers and 90 age- and gender-matched control subjects in Durango City, Mexico using an enzyme immunoassay. Data were analyzed by bivariate and multivariate analyses. Results The prevalence of anti-Leptospira IgG antibodies was similar in waste pickers (4/90: 4.4%) to that in control subjects (5/90: 5.6%) (P = 1.00). Bivariate analysis showed that Leptospira exposure in waste pickers was associated with increasing age (P = 0.009), no education (P = 0.008), and consumption of rat meat (P = 0.04). However, these associations were no longer found by multivariate analysis. Leptospira exposure in waste pickers was not associated with health status, duration in the activity, wearing hand gloves and facemasks, history of injuries with sharp material of the garbage, or contact with animals or soil. Conclusions This is the first study about Leptospira exposure in waste pickers. Results suggest that waste pickers are not at increasing risk for Leptospira exposure in Durango City, Mexico. Further research with a larger sample size to elucidate the association of Leptospira exposure with waste picking activity is needed. PMID:26124911

  3. Are family variables associated with ADHD, inattentive type? A case-control study in schools.

    PubMed

    Pheula, Gabriel Ferreira; Rohde, Luis Augusto; Schmitz, Marcelo

    2011-03-01

    Attention-deficit/hyperactivity disorder (ADHD) seems to be associated with significant psychosocial adversity. However, few studies assessed the role of environmental, social and interpersonal factors specifically in ADHD, inattentive type (ADHD-I). Thus, this study aims to investigate whether family environment risk factors are associated with ADHD-I. In a case-control study, we assessed a non-referred sample of 100 children and adolescents with ADHD-I and 100 non-ADHD controls (6-18 years old). They were systematically evaluated through structured diagnostic interviews. The following family adversity measures were used: Rutter's family adversity index (marital discord, low social class, large family size, paternal criminality, maternal mental disorder), Family Environment Scale (FES) (subscores of cohesion, expressiveness and conflict) and Family Relationship Index (FRI) (based on the subscores above). After adjusting for confounding factors (social phobia and maternal history of ADHD), the odds ratio (OR) for ADHD-I increased as the number of Rutter's indicators increased. Families of children with lower FES cohesion subscores presented higher OR for ADHD-I (OR 1.24; 95% confidence interval 1.05-1.45). Lower levels of FRI, a general index of family relationship, were also related to higher risk of ADHD-I (OR 1.11; 95% confidence interval 1.03-1.21). Our findings suggest that family adversity (in general), low family cohesion and low FRI (in particular) are associated with an increase in the risk for ADHD-I. However, the cross-sectional nature of the study limits our ability to infer causality. PMID:21290154

  4. Polybrominated diphenyl ethers in relation to autism and developmental delay: a case-control study

    PubMed Central

    2011-01-01

    Background Polybrominated diphenyl ethers (PBDEs) are flame retardants used widely and in increasing amounts in the U.S. over the last few decades. PBDEs and their metabolites cross the placenta and studies in rodents demonstrate neurodevelopmental toxicity from prenatal exposures. PBDE exposures occur both via breastfeeding and hand-to-mouth activities in small children. Methods Participants were 100 children from the CHARGE (CHildhood Autism Risk from Genetics and the Environment) Study, a case-control epidemiologic investigation of children with autism/autism spectrum disorder, with developmental delay and from the general population. Diagnoses of autism were confirmed by the Autism Diagnostic Observation Schedule and Autism Diagnostic Inventory-Revised, and of developmental delay using the Mullen's Scales of Early Learning and the Vineland Adaptive Behavior Scales. Typically developing controls were those with no evidence of delay, autism, or autism spectrum disorder. Eleven PBDE congeners were measured by gas chromatography/mass spectrometry from serum specimens collected after children were assessed. Logistic regression was used to evaluate the association between plasma PBDEs and autism. Results Children with autism/autism spectrum disorder and developmental delay were similar to typically developing controls for all PBDE congeners, but levels were high for all three groups. Conclusions Plasma samples collected post-diagnosis in this study may not represent early life exposures due to changes in diet and introduction of new household products containing PBDEs. Studies with direct measurements of prenatal or infant exposures are needed to assess the possible causal role for these compounds in autism spectrum disorders. PMID:21205326

  5. Tooth eruption sequence and dental crowding: a case-control study

    PubMed Central

    Moshkelgosha, Vahid; Khosravifard, Negar; Golkari, Ali

    2014-01-01

    When cases of dental crowding are identified and diagnosed promptly, interceptive orthodontics is particularly successful. Aim: To assess the differences in the eruption sequence of the mandibular canine and first premolar teeth in children with and without dental crowding. Materials and Methods: Children who attended the Shiraz Dental School's orthodontic clinic (Iran) from September to December 2012 were enrolled in this case-control study. Tooth size arch length discrepancy (TSALD) of all 8-10 year olds was calculated from patients’ dental models. Thirty-six children were randomly selected from those with TSALD of equal or less than 4mm (those with crowding). Each selected case was matched for sex and age with another child (as control) with TSALD>−4mm attending the same clinic, in the same time period. The existing panoramic radiographs were traced and the eruption percentages were measured for mandibular canine and first premolar teeth. The mean difference between canine and first premolar eruption percentages was compared between the case and control groups using the SPSS (version PASW 18) software and a paired sample t-test. Results: Canine and first premolar eruption percentages in the case group were 65.82±13.00 and 78.92±10.15 percent, respectively. The mean eruption percentages for canines and first premolars of the control group were 74.12±14.55 and 75.47±11.60 percent, respectively. There was a significant difference in pre-eruptive positions of canine and first premolar teeth in those with moderate to severe crowding when compared to the control group (p<0.001). Conclusion: These findings may improve the early diagnosis of children with high risk of developing moderate to severe crowding during mixed dentition. PMID:25110582

  6. Air Pollution and the Risk of Cardiac Defects: A Population-Based Case-Control Study.

    PubMed

    Hwang, Bing-Fang; Lee, Yungling Leo; Jaakkola, Jouni J K

    2015-11-01

    Previous epidemiologic studies have assessed the role of the exposure to ambient air pollution in the development of cardiac birth defects, but they have provided somewhat inconsistent results. To assess the associations between exposure to ambient air pollutants and the risk of cardiac defects, a population-based case-control study was conducted using 1087 cases of cardiac defects and a random sample of 10,870 controls from 1,533,748 Taiwanese newborns in 2001 to 2007.Logistic regression was performed to calculate odds ratios for 10 ppb increases in O3 and 10 μg/m increases in PM10. In addition, we compared the risk of cardiac defects in 4 categories-high exposure (>75th percentile); medium exposure (75th to 50th percentile); low exposure (<50th-25th percentile); reference (<25th percentile) based on the distribution of each pollutant. The risks of ventricular septal defects (VSD), atrial septal defects (ASD), and patent ductus arteriosus (PDA) were associated with 10 ppb increases in O3 exposure during the first 3 gestational months among term and preterm babies. In comparison between high PM10 exposure and reference category, there were statistically significant elevations in the effect estimates of ASD for all and terms births. In addition, there was a negative or weak association between SO2, NO2, CO, and cardiac defects.The study proved that exposure to outdoor air O3 and PM10 during the first trimester of gestation may increase the risk of VSD, ASD, and PDA. PMID:26554783

  7. Water nitrates and CNS birth defects: a population-based case-control study

    SciTech Connect

    Arbuckle, T.E.; Sherman, G.J.; Corey, P.N.; Walters, D.; Lo, B.

    1988-03-01

    The relation between maternal exposure to nitrates in drinking water and risk of delivering an infant with a central nervous system (CNS) malformation was examined by means of a case-control study in New Brunswick, Canada. All cases of CNS defects for a high and a low prevalence area of New Brunswick, for the years 1973-1983, were included in the study. Controls were selected randomly from the livebirth files for the province, matched on county of maternal residence and date of birth. One hundred and thirty (130) cases were identified and individually matched with two controls each. Individual water samples were collected from the case and control mother's address given on the birth or stillbirth records. The study revealed that the effect of nitrate exposure in water was modified by whether the source of the drinking water was a private well or a public municipal distribution system. Compared to a baseline nitrate level of 0.1 ppm, exposure to nitrate levels of 26 ppm from private well water sources was associated with a moderate, but not statistically significant, increase in risk (risk odds ratio = 2.30; 95% confidence interval = 0.73-7.29). If the source of drinking water was a municipal distribution system or a private spring, an increase in nitrate exposure was associated with a decrease in risk of delivering a CNS-malformed infant; however, these effect estimates were not statistically significant. The positive increase in risk with nitrate exposure from well water sources requires further study using a larger case series and a larger proportion of exposures to nitrate levels exceeding 5 ppm.

  8. Self-Efficacy After Life Skills Training: A Case-Control Study

    PubMed Central

    Rezayat, Fatemeh; Dehghan Nayeri, Nahid

    2013-01-01

    Background: Nursing students’ self-efficacy is a predictor for their educational progress. Students, who believe that they can be successful in their studies, are more confident. Therefore, many universities have focused on life skills training programs to improve the mental health of their students. Objectives: This study was conducted to evaluate and compare self-efficacy in two groups of nursing students of Tehran University of Medical Sciences (TUMS). One group of students was trained on life skill programs, and the second group was not trained on the issue. Materials and Methods: A case-control study was conducted on two groups of nursing students in TUMS in the late 2012. The case group (n = 112) had passed life skills training course, and the control group (n = 139) was not trained on the issue. Data was collected using a questionnaire containing 12 questions about demographic features, and the Sherer’s general self-efficacy questionnaire. Data analysis was performed using independent sample t-test, Chi-square, odds ratio, and Fisher’s exact test. Results: In the untrained and trained groups, 23% and 8% of the students had very high self-efficacy, respectively. The overall mean scores of self-efficacy were 41.99 ± 9.31 and 38.99 ± 10.48 in the trained and untrained groups, respectively (P = 0.015), and the higher mean score indicates lower level of self-efficacy. A significant difference was also found between the self-efficacy and family income (P = 0.029). Conclusions: The present study showed that life skills training program did not affect self-efficacy of nursing students. Perhaps, the methods used in education were influencing and then, more effective techniques such as role-play and group discussion should be substituted in life skills training. PMID:25414884

  9. A case control study of a deprivation triangle: teenage motherhood, poor educational achievement and unemployment.

    PubMed

    Bradley, Terry; Cupples, Margaret E; Irvine, Helen

    2002-01-01

    Teenage motherhood has been linked with poor health, poor educational attainment, poor employment prospects and socio-economic deprivation. Much of the evidence has come from large surveys and the nature of these inter-relationships remains unclear. A case-control study was designed to compare the educational and employment experiences of teenage mothers with those of an age matched sample of peers from a similar social background and to test the feasibility of carrying out this type of research within primary care. Participants were identified from records in 36 GP practices in the Greater Belfast area. First time teenage mothers with one child aged 9-15 months at the time of interview were selected. Teenage mothers were matched with a control group of nulliparous teenagers in respect of age and postcode and registered with the same practice. Questionnaires were administered in their home or at their health centre. Data were analysed using SPSS for Windows Version 6. Teenage mothers were less likely than controls to have gained passes in school leaving examinations. None of the mothers was in full time education compared with 35% of the controls. Excluding those in education or training, more of the control group were employed at the time of study (82% v 11%). It is concluded that teenage mothers with one child report poorer educational attainment and employment status than their nulliparous peers from a similar social background with similar educational opportunities. Attention must be paid to these findings when planning policy to help teenage mothers and avoid perpetuation of a cycle of socio-economic deprivation.

  10. Determinants of Visceral Leishmaniasis: A Case-Control Study in Gedaref State, Sudan

    PubMed Central

    Salih, Niven; Elhag, Mousab Siddig; Elbadawi, Mobarak Elnour; Hammam, Omer; Mumina, Ann; Atia, Atia Abdalla; Etard, Jean-François; Ritmeijer, Koert; Chappuis, François

    2015-01-01

    Background Improving knowledge on local determinants of visceral leishmaniasis (VL) is crucial to guide the development of relevant control strategies. This study aimed to identify individual and household level determinants of primary VL in 24 highly endemic villages of Tabarak Allah hospital’s catchment area, Gedaref State, Sudan. Methods From September 2012 to July 2013, in an unmatched case-control design, 198 patients with primary VL were compared to 801 controls free of VL symptoms and with a negative VL rapid test. Using random spatial sampling, controls were selected with a distribution of age, sex and village of residence proportionate to the distribution of the target population. Data were collected using a structured questionnaire. Results Children and men were at higher risk of VL. Reporting VL patient(s) in the household in the previous year was the strongest VL risk factor. In a multivariate analysis, VL risk increased with household size, sleep location (outside the yard, not in the farm), evening outdoor activities in the rainy season (playing, watching TV, radio listening), use of ground nut oil as animal repellent and of smoke of Acacia seyal as indoor repellent, presence of dogs in the yard at night, Acacia nilotica in the yard’s immediate surroundings and of a forest at eye range. VL risk appeared to decrease with the use of drinking water sources other than the village water tank, a buffer distance from the adjacent house yard, and with the presence of animals other than dogs in the yard at night. In contrast with previous studies, housing factors, mosquito-net use, black cotton soil, ethnicity, socioeconomic index, presence of Balanites aegyptica and Azadirachta indica in the yard were not independent VL determinants. Discussion and conclusion Although these results do not provide evidence of causality, they provide useful suggestions for guiding further intervention studies on VL preventive measures. PMID:26544177

  11. Risk factors for contracting watery diarrhoea in Kadoma City, Zimbabwe, 2011: a case control study

    PubMed Central

    2013-01-01

    Background Kadoma City experienced an increase in watery diarrhoea from 27 cases during week beginning 5th September, to 107 cases during week beginning 26th September 2011. The weekly diarrhoea cases crossed the threshold action line during week beginning 5th September at the children’s clinic in Rimuka Township, and the remaining four clinics reported cases crossing threshold action lines between week beginning 12th September and week beginning 26th September. Eighty-two percent of the cases were children less than 5 years old. We conducted a case controlstudy to determine risk factorsfor contracting watery diarrhoea in children less than 5 years in Kadoma City. Methods An unmatched 1:1 case control study was conducted in Ngezi and Rimuka townships in Kadoma City, Zimbabwe. A case was a child less than 5 years old, who developed acute watery diarrhoea between 5th September and 1st October 2011. A control was a child less than 5 years old who stayed in the same township and did not suffer from diarrhoea. A structured questionnaire was administered to caregivers of cases and controls.Laboratory water quality tests and stool test results were reviewed.Epi Info™ statistical software was used to analyse data. Results A total of 109 cases and 109 controls were enrolled. Independent protective factors were: having been exclusively breastfed for six months [AOR = 0.44; 95% CI (0.24-0.82)]; using municipal water [AOR = 0.38; 95% CI (0.18-0.80)]; using aqua tablets, [AOR = 0.49; 95% CI (0.26–0.94)] and; storing water in closed containers, [AOR = 0.24; 95% CI (0.07–0.0.83). The only independent risk factor for contracting watery diarrhoea was hand washing in a single bowl, [AOR = 2.89; 95% CI (1.33–6.28)]. Salmonella, Shigella, Rotavirus, and Enteropathogenic Escherichia coli were isolated in the stool specimens. None of the 33 municipal water samples tested showed contamination with Escherichia coli, whilst 23 of 44 (52%) shallow well water samples and 3 of 15

  12. Asthma-susceptibility variants identified using probands in case-control and family-based analyses

    PubMed Central

    2010-01-01

    Background Asthma is a chronic respiratory disease whose genetic basis has been explored for over two decades, most recently via genome-wide association studies. We sought to find asthma-susceptibility variants by using probands from a single population in both family-based and case-control association designs. Methods We used probands from the Childhood Asthma Management Program (CAMP) in two primary genome-wide association study designs: (1) probands were combined with publicly available population controls in a case-control design, and (2) probands and their parents were used in a family-based design. We followed a two-stage replication process utilizing three independent populations to validate our primary findings. Results We found that single nucleotide polymorphisms with similar case-control and family-based association results were more likely to replicate in the independent populations, than those with the smallest p-values in either the case-control or family-based design alone. The single nucleotide polymorphism that showed the strongest evidence for association to asthma was rs17572584, which replicated in 2/3 independent populations with an overall p-value among replication populations of 3.5E-05. This variant is near a gene that encodes an enzyme that has been implicated to act coordinately with modulators of Th2 cell differentiation and is expressed in human lung. Conclusions Our results suggest that using probands from family-based studies in case-control designs, and combining results of both family-based and case-control approaches, may be a way to augment our ability to find SNPs associated with asthma and other complex diseases. PMID:20698975

  13. Mortality from Circulatory System Diseases among French Uranium Miners: A Nested Case-Control Study.

    PubMed

    Drubay, Damien; Caër-Lorho, Sylvaine; Laroche, Pierre; Laurier, Dominique; Rage, Estelle

    2015-05-01

    A significant association has been observed between radon exposure and cerebrovascular disease (CeVD) mortality among French uranium miners, but risk factors for circulatory system diseases (CSD) have not been previously considered. We conducted new analyses in the recently updated (through 2007) French cohort of uranium miners (n = 5,086), which included 442 deaths from CSD, 167 of them from ischemic heart disease (IHD) and 105 from CeVD. A nested case-control study was then set up to collect and investigate the influence of these risk factors on the relationships between mortality from CSD and occupational external gamma ray and internal ionizing radiation exposure (radon and long-lived radionuclides) in this updated cohort. The nested case-control study included miners first employed after 1955, still employed in 1976 and followed up through 2007. Individual information about CSD risk factors was collected from medical files for the 76 deaths from CSD (including 26 from IHD and 16 from CeVD) and 237 miners who had not died of CSD by the end of follow-up. The exposure-risk relationships were assessed with a Cox proportional hazard model weighted by the inverse sampling probability. A significant increase in all CSD and CeVD mortality risks associated with radon exposure was observed in the total cohort [hazard ratios: HRCSD/100 working level months (WLM) = 1.11, 95% confidence interval (1.01; 1.22) and HRCeVD/100 WLM = 1.25 (1.09; 1.43), respectively]. A nonsignificant exposure-risk relationship was observed for every type of cumulative ionizing radiation exposure and every end point [e.g., HRCSD/100WLM = 1.43 (0.71; 2.87)]. The adjustment for each CSD risk factor did not substantially change the exposure-risk relationships. When the model was adjusted for overweight, hypertension, diabetes, hypercholesterolemia and smoking status, the HR/100WLM for CSD, for example, was equal to 1.21 (0.54; 2.75); and when it was adjusted for risk factors selected with the

  14. Lipid Peroxidation and Antioxidant Status in Patients with Medullary Thyroid Carcinoma: A Case-Control Study

    PubMed Central

    Hosseini-Zijoud, Seyed-Mostafa; Ebadi, Seyed Alireza; Goodarzi, Mohammad Taghi; Hedayati, Mehdi; Abbasalipourkabir, Roghayeh; Mahjoob, Mohammad Parsa; Poorolajal, Jalal; Zicker, Fabio

    2016-01-01

    Introduction Oxidative stress or oxidant/antioxidant imbalance has a crucial role in the pathogenesis of some diseases like cancer. Medullary thyroid carcinoma (MTC) originates in the thyroid parafollicular cells and includes 3-4% of the malignant neoplasms that have an effect on this gland. The aetiology of MTC has not been clarified. However, oxidative stress may be one of the factors involved. Aim The aim of the current study was to evaluate the antioxidant enzyme activity of catalase (CAT), Glutathione (GSH), total antioxidant capacity (TAC) and the levels of the lipid peroxidation product malondialdehyde (MDA) in blood samples of MTC patients as compared to healthy controls. Materials and Methods A case-control study was designed enrolling patients with confirmed MTC diagnosis and age-and sex group matched healthy volunteers referred to the clinic of the Research Institute for Endocrine Sciences, Tehran, Iran from April 2013 to July 2015. Fasting blood samples were taken for study. Catalase, GSH, MDA and TAC levels were measured by colorimetry using commercial kits (ZellBio GmbH, Germany). Data were analysed using SPSS 17 software, comparing mean±SD through t-test and difference between proportions through chi-square. Results No statistical difference was observed in the demographic characteristic between cases and controls. The final MTC group included 40 males and 45 females with a mean age of 30±12.9 year, and the control group 40 males and 47 females, with a mean age of 31.2±12.3 year. Anthropometric parameters, dietary and thyroid hormones levels (T3, T4 and TSH) were similar. Serum TAC (p=0.015), GSH (p=0.029) and CAT (p<0.001) levels were found to be significantly lower in the MTC patients, while serum MDA levels were significantly higher in MTC patients than controls (p<0.001). Conclusion These preliminary findings suggest that oxidant/antioxidant imbalance may be associated with or possibly indicate an increased risk to medullary thyroid carcinoma

  15. No association between ZNF804A rs1344706 and schizophrenia in a case-control study of Han Chinese.

    PubMed

    Wang, Jun; Zhao, Shuidi; Shugart, Yin Yao; Zhou, Zhenhe; Jin, Chunhui; Yuan, Jianmin; Wang, Guoqiang; Wang, Dong; Cheng, Zaohuo; Zhang, Fuquan

    2016-04-01

    Previous studies indicated that the single nucleotide polymorphism (SNP) rs1344706 within the gene ZNF804A was a promising risk variant for schizophrenia in European populations. However, existing results are inconsistent in Han Chinese. Hoping to validate the association of rs1344706 with schizophrenia susceptibility in Han Chinese, we conducted a case-control study in 1284 cases and 990 healthy controls from Jiangsu Province, China. We did not detect any significant between-group difference (all P>0.05) in either allele or genotype frequency under any genetic model between cases and controls. Stratified analysis by sex also failed to find any significant association. Our results did not support the association of rs1344706 with schizophrenia in Han Chinese, and further association studies with large samples from other ethnic backgrounds and focus on more SNPs of ZNF804A are warranted. PMID:26934312

  16. SV40 enhances the risk of malignant mesothelioma among people exposed to asbestos: a molecular epidemiologic case-control study.

    PubMed

    Cristaudo, Alfonso; Foddis, Rudy; Vivaldi, Agnese; Buselli, Rodolfo; Gattini, Vittorio; Guglielmi, Giovanni; Cosentino, Francesca; Ottenga, Franco; Ciancia, Eugenio; Libener, Roberta; Filiberti, Rosangela; Neri, Monica; Betta, Piergiacomo; Tognon, Mauro; Mutti, Luciano; Puntoni, Riccardo

    2005-04-15

    We conducted a case-control study on asbestos exposure and presence of SV40 in tumor samples of malignant mesotheliomas (MMs) and bladder urotheliomas (BUs). PCR analysis revealed the presence of SV40 DNA (SV40+) in eight (42.1%) MMs and 6 (33.3%) BUs. The odds ratio for MM Asb- and SV40+ was 0.4 [95% confidence interval (95% CI), 0.03-4.0], for Asb+ and SV40- was 3.6 (95% CI, 0.6-21.0), and for Asb+ and SV40+ was 12.6 (95% CI, 1.2-133.9). Our results suggest that SV40 increases the risk of MM among individuals exposed to asbestos.

  17. A gene-based information gain method for detecting gene-gene interactions in case-control studies.

    PubMed

    Li, Jin; Huang, Dongli; Guo, Maozu; Liu, Xiaoyan; Wang, Chunyu; Teng, Zhixia; Zhang, Ruijie; Jiang, Yongshuai; Lv, Hongchao; Wang, Limei

    2015-11-01

    Currently, most methods for detecting gene-gene interactions (GGIs) in genome-wide association studies are divided into SNP-based methods and gene-based methods. Generally, the gene-based methods can be more powerful than SNP-based methods. Some gene-based entropy methods can only capture the linear relationship between genes. We therefore proposed a nonparametric gene-based information gain method (GBIGM) that can capture both linear relationship and nonlinear correlation between genes. Through simulation with different odds ratio, sample size and prevalence rate, GBIGM was shown to be valid and more powerful than classic KCCU method and SNP-based entropy method. In the analysis of data from 17 genes on rheumatoid arthritis, GBIGM was more effective than the other two methods as it obtains fewer significant results, which was important for biological verification. Therefore, GBIGM is a suitable and powerful tool for detecting GGIs in case-control studies.

  18. Reliability of 3-Dimensional Measures of Single-Leg Drop Landing Across 3 Institutions: Implications for Multicenter Research for Secondary ACL-Injury Prevention

    PubMed Central

    Myer, Gregory D.; Bates, Nathaniel A.; DiCesare, Christopher A.; Barber Foss, Kim D.; Thomas, Staci M.; Wordeman, Samuel C.; Sugimoto, Dai; Roewer, Benjamin D.; Medina McKeon, Jennifer M.; Di Stasi, Stephanie L.; Noehren, Brian W.; McNally, Michael; Ford, Kevin R.; Kiefer, Adam W.; Hewett, Timothy E.

    2016-01-01

    Context Due to the limitations of single-center studies in achieving appropriate sampling with relatively rare disorders, multicenter collaborations have been proposed to achieve desired sampling levels. However, documented reliability of biomechanical data is necessary for multicenter injury-prevention studies and is currently unavailable. Objective To measure the reliability of 3-dimensional (3D) biomechanical waveforms from kinetic and kinematic variables during a single-leg landing (SLL) performed at 3 separate testing facilities. Design Multicenter reliability study. Setting 3 laboratories. Patients 25 female junior varsity and varsity high school volleyball players who visited each facility over a 1-mo period. Intervention Subjects were instrumented with 43 reflective markers to record 3D motion as they performed SLLs. During the SLL the athlete balanced on 1 leg, dropped down off of a 31-cm-high box, and landed on the same leg. Kinematic and kinetic data from both legs were processed from 2 trials across the 3 laboratories. Main Outcome Measures Coefficients of multiple correlations (CMC) were used to statistically compare each joint angle and moment waveform for the first 500 ms of landing. Results Average CMC for lower-extremity sagittal-plane motion was excellent between laboratories (hip .98, knee .95, ankle .99). Average CMC for lower-extremity frontal-plane motion was also excellent between laboratories (hip .98, knee .80, ankle .93). Kinetic waveforms were repeatable in each plane of rotation (3-center mean CMC ≥.71), while knee sagittal-plane moments were the most consistent measure across sites (3-center mean CMC ≥.94). Conclusions CMC waveform comparisons were similar relative to the joint measured to previously published reports of between-sessions reliability of sagittal- and frontal-plane biomechanics performed at a single institution. Continued research is needed to further standardize technology and methods to help ensure that highly

  19. Behavioural Comorbidity in Tanzanian Children with Epilepsy: A Community-Based Case-Control Study

    ERIC Educational Resources Information Center

    Burton, Kathryn; Rogathe, Jane; Hunter, Ewan; Burton, Matthew; Swai, Mark; Todd, Jim; Neville, Brian; Walker, Richard; Newton, Charles

    2011-01-01

    Aim: The aim of this study was to define the prevalence of and risk factors for behavioural disorders in children with epilepsy from a rural district of Tanzania by conducting a community-based case-control study. Method: One hundred and twelve children aged 6 to 14 years (55 males, 57 females; median age 12y) with active epilepsy (at least two…

  20. Excess relative risk as an effect measure in case-control studies of rare diseases.

    PubMed

    Lee, Wen-Chung

    2014-01-01

    Epidemiologists often use ratio-type indices (rate ratio, risk ratio and odds ratio) to quantify the association between exposure and disease. By comparison, less attention has been paid to effect measures on a difference scale (excess rate or excess risk). The excess relative risk (ERR) used primarily by radiation epidemiologists is of peculiar interest here, in that it involves both difference and ratio operations. The ERR index (but not the difference-type indices) is estimable in case-control studies. Using the theory of sufficient component cause model, the author shows that when there is no mechanistic interaction (no synergism in the sufficient cause sense) between the exposure under study and the stratifying variable, the ERR index (but not the ratio-type indices) in a rare-disease case-control setting should remain constant across strata and can therefore be regarded as a common effect parameter. By exploiting this homogeneity property, the related attributable fraction indices can also be estimated with greater precision. The author demonstrates the methodology (SAS codes provided) using a case-control dataset, and shows that ERR preserves the logical properties of the ratio-type indices. In light of the many desirable properties of the ERR index, the author advocates its use as an effect measure in case-control studies of rare diseases.

  1. Toxoplasmosis gondii and schizophrenia: a case control study in a low Toxoplasma gondii seroprevalence Mexican population

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  2. COMPARISON OF GEOCODING METHODS USED IN CASE-CONTROL STUDY OF AIR QUALITY AND BIRTH DEFECTS

    EPA Science Inventory

    Introduction: Accurate geocoding of maternal residence is critical to the success of an ongoing case-control study of exposure to five criteria air pollutants and the risk of selected birth defects in seven Texas counties between 1997 and 2000. The geocoded maternal residence a...

  3. Ear Playing and Aural Development in the Instrumental Lesson: Results from a "Case-Control" Experiment

    ERIC Educational Resources Information Center

    Baker, David; Green, Lucy

    2013-01-01

    This article reports on a case-control experiment that was conducted in 2012 as part of the Ear Playing Project (EPP) at the Institute of Education, University of London. The EPP developed from the "informal learning" strand of Musical Futures and engaged instrumental students in the UK in learning from specially-created audio recordings…

  4. Case-Control Genome-Wide Association Study of Attention-Deficit/Hyperactivity Disorder

    ERIC Educational Resources Information Center

    Neale, Benjamin M.; Medland, Sarah; Ripke, Stephan; Anney, Richard J. L.; Asherson, Philip; Buitelaar, Jan; Franke, Barbara; Gill, Michael; Kent, Lindsey; Holmans, Peter; Middleton, Frank; Thapar, Anita; Lesch, Klaus-Peter; Faraone, Stephen V.; Daly, Mark; Nguyen, Thuy Trang; Schafer, Helmut; Steinhausen, Hans-Christoph; Reif, Andreas; Renner, Tobias J.; Romanos, Marcel; Romanos, Jasmin; Warnke, Andreas; Walitza, Susanne; Freitag, Christine; Meyer, Jobst; Palmason, Haukur; Rothenberger, Aribert; Hawi, Ziarih; Sergeant, Joseph; Roeyers, Herbert; Mick, Eric; Biederman, Joseph

    2010-01-01

    Objective: Although twin and family studies have shown attention-deficit/hyperactivity disorder (ADHD) to be highly heritable, genetic variants influencing the trait at a genome-wide significant level have yet to be identified. Thus additional genome-wide association studies (GWAS) are needed. Method: We used case-control analyses of 896 cases…

  5. Nutritional Status of Children with Autism Spectrum Disorders (ASDs): A Case-Control Study

    ERIC Educational Resources Information Center

    Marí-Bauset, Salvador; Llopis-González, Agustín; Zazpe-García, Itziar; Marí-Sanchis, Amelia; Morales-Suárez-Varela, María

    2015-01-01

    Children with autism spectrum disorder (ASD) have problems of food selectivity, implying risks of nutritional deficiencies. The aim was to compare intakes of macro and micronutrients and body mass index in ASD and typically developing (TD) children. In a case--control study, 3-day food diaries and anthropometric measurements were completed for ASD…

  6. National Case-Control Study of Homicide Offending and Methamphetamine Use

    ERIC Educational Resources Information Center

    Stretesky, Paul B.

    2009-01-01

    The purpose of this study is to examine the relationship between methamphetamine use and homicide. To carry out this study, data from the National Household Survey on Drug Abuse and Survey of Inmates in State and Federal Correctional Facilities were combined to create a case-control design. The main exposure measure is methamphetamine use and the…

  7. 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…

  8. Lack of association of dairy food, calcium, and vitamin D intake with the risk of Parkinson's disease: a case-control study in Japan.

    PubMed

    Miyake, Y; Tanaka, K; Fukushima, W; Sasaki, S; Kiyohara, C; Tsuboi, Y; Yamada, T; Oeda, T; Miki, T; Kawamura, N; Sakae, N; Fukuyama, H; Hirota, Y; Nagai, M

    2011-02-01

    Three previous cohort studies in the USA reported that dairy product consumption was significantly associated with an increased risk of Parkinson's disease (PD) in men, but not in women. We examined the relationship between consumption of dairy products, calcium, and vitamin D and the risk of PD using data from a multicenter hospital-based case-control study in Japan. Included were 249 cases within 6 years of onset of PD based on the UK PD Society Brain Bank clinical diagnostic criteria. Controls were 368 inpatients and outpatients without a neurodegenerative disease. Information on dietary factors was collected using a validated self-administered diet history questionnaire. Adjustment was made for sex, age, region of residence, pack-years of smoking, years of education, body mass index, and dietary factors including cholesterol, dietary glycemic index, vitamin E, β-carotene, vitamin B(6), caffeine, iron, and alcohol. Total dairy product consumption was not materially associated with the risk of PD (P for trend = 0.62). No evident relationships were observed between intake of milk, yogurt, cheese, or ice cream and the risk of PD (P for trend = 0.75, 0.63, 0.59, and 0.35, respectively). There were no measurable associations between consumption of calcium or vitamin D and PD (P for trend = 0.37 and 0.69, respectively). No significant interactions were observed between the dietary exposures and sex regarding PD. Our results suggest that intake of dairy products, calcium, and vitamin D was not related to PD, regardless of sex. However, such null relationships might be a consequence of PD. PMID:21169048

  9. A Multi-Center, Cross-Sectional Study on the Burden of Infectious Keratitis in China

    PubMed Central

    Song, Xiusheng; Xie, Lixin; Tan, Xiaodong; Wang, Zhichong; Yang, Yanning; Yuan, Yuansheng; Deng, Yingping; Fu, Shaoying; Xu, Jianjiang; Sun, Xuguang; Sheng, Xunlun; Wang, Qing

    2014-01-01

    Objective To understand the prevalence and demographic characteristics of infectious keratitis and infectious corneal blindness. Methods A multi-center, population-based cross-sectional study was conducted from January 1 to August 31, 2010. A total of 191,242 individuals of all age groups from 10 geographically representative provinces were sampled using stratified, multi-stage, random and systematic sampling procedures. A majority, 168,673 (88.2%), of those sampled participated in the study. The examination protocol included a structured interview, visual acuity testing, an external eye examination, and an anterior segment examination using a slit lamp. The causes and sequelae of corneal disease were identified using uniform customized protocols. Blindness in one eye caused by infectious keratitis was defined as infectious corneal blindness. Results The prevalence of past and active infectious keratitis was 0.192% (95% confidence interval [CI], 0.171–0.213%), and the prevalence of viral, bacterial, and fungal keratitis was 0.11%, 0.075%, and 0.007%, respectively. There were 138 cases of infectious corneal blindness in at least one eye in the study population (prevalence of 0.082% [95%CI, 0.068%–0.095%]). Statistical analysis suggested that ocular trauma, alcoholic consumption, low socioeconomic levels, advanced age, and poor education were risk factors for infectious corneal blindness. Conclusions Infectious keratitis is the leading cause of corneal blindness in China. Eye care strategies should focus on the prevention and rehabilitation of infectious corneal blindness. PMID:25438169

  10. Multi-center, multi-topic heart sound databases and their applications.

    PubMed

    Xie, Meilan; Xiao, Shouzhong; Liu, Tianhu; Yi, Qijian; You, Fengzhi; Guo, Xingming; Shao, Yong; Huo, Junmimg; Du, Deqi; Xu, Dongmei; Wu, Wenzhu; Xiao, Zifu; Yang, Yong; Guo, Weizhen

    2012-02-01

    This paper describes a large resource of multi-center and multi-topic heart sound databases, which were based on the measured data from more than 9,000 heart sound samples (saved in WAV file format). According to different research topics, these samples were respectively stored in different folders (corresponding to different research topics and distributed over various cooperative research centers), most of which as subfolds were stored in a pooled folder in the principal center. According to different research topics, the measured data from these samples were used to create different databases. Relevant data for a specific topic can be pooled in a large database for further analysis. This resource is shared by members of related centers for their own specific topic. The applications of this resource include evaluation of cardiac safety of pregnant women, evaluation of cardiac reserve for children, athletes, addicts, astronauts, and general populations, as well as studies on a bedside method for evaluating cardiac energy, reversal of S1-S2 ratio, etc.

  11. Prescription Acquired Acetaminophen Use and the Risk of Asthma in Adults: A Case Control Study

    PubMed Central

    Kelkar, Mugdha; Cleves, Mario A.; Foster, Howell R.; Hogan, William R.; James, Laura P.

    2013-01-01

    Background Studies have examined the association between acetaminophen (APAP) use and asthma; however, their interpretation is limited by a number of methodological issues. Objective We sought to investigate the association between recent and chronic prescription acquired acetaminophen use and asthma. Methods This was a retrospective case control study using a 10% random sample of the IMS LifeLink commercial claims data from 1997 to 2009. Cases had to have at least 1 incident claim of asthma. 3:1 controls matched on age, gender, and region were randomly chosen. APAP exposure, dose and duration were measured in the 7 and 30 days (recent) and in the 1-year (chronic) look-back period. Multivariable conditional logistic regression was used to estimate the risk of asthma associated with acetaminophen use adjusted for comorbidities, other drugs increasing asthma risk, and health system factors. Results There were 28,892 cases and 86,676 controls with mean age 42.7 years and 37.7% were males. 22.6% cases and 18.2% controls had APAP exposure in the pre-index year with mean cumulative doses of 78.7 gm and 59.8 gm respectively. There was no significant association between recent prescription APAP exposure and asthma (7 days: OR = 1.02, p = 0.74; 30 days: OR = 0.97, p = 0.38). Cumulative prescription APAP dose in the year prior increased asthma risk compared to APAP nonusers (<=1 kg: OR = 1.09, p <0.001 and >1 kg: OR = 1.60, p=0.02). Duration of prescription APAP use >30 days was associated with elevated asthma risk (OR = 1.39, p <0.001). Conclusion Chronic prescription-acquired APAP use was associated with an increased risk of asthma while recent use was not. However, over the counter APAP use was not captured in this study and further epidemiologic research with complete APAP exposure ascertainment and research on pathophysiological mechanisms is needed to confirm these relationships. PMID:23170033

  12. Individual and occupational risk factors for knee osteoarthritis – Study protocol of a case control study

    PubMed Central

    Klußmann, André; Gebhardt, Hansjuergen; Liebers, Falk; von Engelhardt, Lars Victor; Dávid, Andreas; Bouillon, Bertil; Rieger, Monika A

    2008-01-01

    Background Knee osteoarthritis (OA) is one of the frequent and functionally impairing disorders of the musculoskeletal system. In the literature, a number of occupational risk factors are discussed as being related to the development and progress of knee joint diseases, e.g. working in kneeling or squatting posture, lifting and carrying of heavy weights. The importance of the single risk factors and the possibility of prevention are currently under discussion. Besides the occupational factors, a number of individual risk factors are important, too. The distinction between work-related factors and individual factors is crucial in assessing the risk and in deriving preventive measures in occupational health. In existing studies, the occupational stress is determined mainly by surveys in employees and/or by making assumptions about individual occupations. Direct evaluation of occupational exposure has been performed only exceptionally. The aim of the research project ArGon is the assessment of different occupational factors in relation to individual factors (e.g. constitutional factors, leisure time activities, sports), which might influence the development and/or progression of knee (OA). The project is designed as a case control study. Methods/Design To raise valid data about the physical stress associated with occupational and leisure time activities, patients with and without knee OA are questioned by means of a standardised questionnaire and an interview. The required sample size was estimated to 800 cases and an equal number of controls. The degree and localisation of the knee cartilage or joint damages in the cases are documented on the basis of radiological, arthroscopic and/or operative findings in a patient record. Furthermore, occupational exposure is analysed at selected workplaces. To evaluate the answers provided in the questionnaire, work analysis is performed. Discussion In this research project, specific information on the correlation of occupational

  13. Case-control study of occupational exposures and male breast cancer

    PubMed Central

    Cocco, P.; Figgs, L.; Dosemeci, M.; Hayes, R.; Linet, M. S.; Hsing, A. W.

    1998-01-01

    OBJECTIVE: To investigate whether risk of male breast cancer is associated with workplace exposures. METHODS: A case-control study of 178 cases of male breast cancer and 1041 controls was carried out with data from the United States national mortality follow-back survey, which collected questionnaire information from proxy respondents of a 1% sample of all 1986 United States deaths among subjects aged 25-74 years. Occupational exposure to electromagnetic fields, high temperatures, polycyclic aromatic hydrocarbons (PAHs), herbicides, other pesticides, and organic solvents was assessed by applying job- exposure matrices, based on the 1980 United States census occupation and industry codes, to the longest job held by study subjects as reported by the informants. A socioeconomic status index was created by combining information on annual family income, education, assets, and occupation to assess the association of socioeconomic status with male breast cancer. Relative risks were derived from logistic regression modelling, which included age, socioeconomic status, marital status, and body mass index, as well as occupational exposures. RESULTS: Risk for male breast cancer increased significantly with increasing socioeconomic status index (test for trend: p < 0.01), but the risks associated with individual socioeconomic status variables were smaller and the trends were not significant. A significant increase in risk of male breast cancer was associated with employment in blast furnaces, steel works, and rolling mills (odds ratio (OR) 3.4; 95% confidence interval (95% CI) 1.1 to 10.1, based on six cases), and motor vehicle manufacturing (OR 3.1; 95% CI 1.2 to 8.2, based on seven cases). However, exposures to electromagnetic fields, high temperature, PAHs, herbicides, other pesticides, and organic solvents were not associated with risk of male breast cancer. CONCLUSIONS: The role of workplace exposures in increasing risk of breast cancer among men employed in motor vehicle

  14. Healthy Eating Index in Patients With Cataract: A Case-Control Study

    PubMed Central

    Ghanavati, Matin; Behrooz, Maryam; Rashidkhani, Bahram; Ashtray-Larky, Damoon; Zameni, Seyed Davood; Alipour, Meysam

    2015-01-01

    Background: Nutritional factors play an important role in cataract disease and the healthy eating index (HEI) is a unique approach to study the relationships between diet and diseases. Objectives: The current study aimed to evaluate and compare healthy eating index among the patients with cataract and healthy individuals. Patients and Methods: This case-control study was conducted on 97 patients with cataract and 198 healthy people (as a control group) in Iran. Individuals were selected by the convenience sampling method and the food frequency questionnaire (FFQ) was completed for them. At first, HEI was calculated and then the HEI scores were compared in cataract patients and healthy individuals. Results: The analysis of FFQ showed that the scores of vegetables (7.81 v. 10), nutritional variation (5.5 v. 7) and sodium (2 v. 6) groups (P < 0.001) were significantly lower among the patients with cataract than the healthy individuals. Also this significant difference was observed in the scores of total HEI and fruits (respectively 73.26 v.79.30 and 7.1 v. 9.8) (P < 0.01). On the other hand, the scores of saturated fatty acids (10 v. 9; P = 0.02), total fat (8 v. 7; P = 0.004) and cereals (10 v. 10; P < 0.001) were higher among the patients with cataract than the healthy individuals. The comparison of dietary intake among all types of cataract shows that the scores of the meat group were significantly higher in the patients with nuclear cataract and mixed cataract than the ones with posterior cataract (respectively 9.4 v. 6.5 and 9 v. 6.5) (P = 0.02). In addition, after adjusting the confounding factors the results showed that the HEI high score was associated with reducing the risk of coming down with cataract (OR = 0.18, CI: 95%, P < 0.001, 0.08 - 0.41). Conclusions: The results of the current study suggest that increasing the quality of the diet calculated according to HEI can reduce the risk of coming down with cataract. PMID:26568860

  15. [Multicenter trial for sudden hearing loss therapy - planning and concept].

    PubMed

    Plontke, S K; Girndt, M; Meisner, C; Probst, R; Oerlecke, I; Richter, M; Steighardt, J; Dreier, G; Weber, A; Baumann, I; Plößl, S; Löhler, J; Laszig, R; Werner, J A; Rahne, T

    2016-04-01

    Systemic steroids are widely used worldwide as a standard of care for primary therapy of idiopathic sudden sensorineural hearing loss (ISSHL). The German ISSHL guideline recommends high-dose steroids for primary therapy of ISSHL, without evidence from randomized controlled trials (RCTs). The rationale for the treatment of ISSHL using high dose steroids is only based on retrospective cohort studies.This article describes the planning and initiation of a multicenter, national, randomized, controlled clinical trial entitled Efficacy and safety of high dose glucocorticosteroid treatment for idiopathic sudden sensorineural hearing loss - a three-armed, randomized, triple-blind, multicenter trial (HODOKORT). This clinical trial aims to compare standard dose with two types of high-dose steroids for primary systemic therapy with respect to their efficacy in improving hearing, and thus communication ability, in patients with idiopathic sudden sensorineural hearing loss.This study is funded by the "Clinical Trials with High Patient Relevance" research program in the health research framework of the German Federal Ministry of Education and Research. It is one of two studies by the German Study Center of Clinical Trials of the German Society of Otorhinolaryngology, Head and Neck Surgery (DSZ-HNO). Planning and initiation was done in cooperation with the DSZ-HNO, the Coordination Center of Clinical Trials of the Martin-Luther-University Halle-Wittenberg, and the Study Center of the University Hospital Freiburg. PMID:27038034

  16. Rhinorrhea in Parkinson's disease: a consecutive multicenter study in Japan.

    PubMed

    Kano, Osamu; Yoshioka, Masayuki; Nagayama, Hiroshi; Hamada, Shinsuke; Maeda, Tetsuya; Hasegawa, Takafumi; Kadowaki, Taro; Sengoku, Renpei; Terashi, Hiroo; Hatano, Taku; Nomoto, Nobuatsu; Inoue, Manabu; Shimura, Hideki; Takahashi, Tatsuya; Uchiyama, Tsuyoshi; Watanabe, Hirohisa; Kaneko, Satoshi; Takahashi, Tetsuya; Baba, Yasuhiko; Kubo, Shin-Ichiro

    2014-08-15

    Recent reports suggest that rhinorrhea, defined as the presence of a runny nose unrelated to respiratory infections, allergies, or sinus problems, occurs more frequently among patients with Parkinson's disease (PD) than among healthy controls. We conducted a questionnaire survey in a multicenter study throughout Japan and compared the frequency of rhinorrhea between 231 PD and 187 normal control (NC) subjects. After excluding patients with rhinitis or paranasal sinusitis, a total of 159 PD and 59 NC subjects were included in our analysis. Rhinorrhea occurred more frequently in PD patients than NC subjects (33.3% vs. 11.9%; P=0.01). Among PD patients, rhinorrhea was more common in men than women (P=0.005). Rhinorrhea was not correlated with disease duration, modified Hoehn and Yahr score, disease type (akinesia rigidity vs. tremor dominant), or cardiac sympathetic function (evaluated by (123)I-metaiodobenzylguanidine uptake). To our knowledge, this is the first multicenter study on the frequency of PD-related rhinorrhea in Asian countries. PMID:24932941

  17. [Multicenter trial for sudden hearing loss therapy - planning and concept].

    PubMed

    Plontke, S K; Girndt, M; Meisner, C; Probst, R; Oerlecke, I; Richter, M; Steighardt, J; Dreier, G; Weber, A; Baumann, I; Plößl, S; Löhler, J; Laszig, R; Werner, J A; Rahne, T

    2016-04-01

    Systemic steroids are widely used worldwide as a standard of care for primary therapy of idiopathic sudden sensorineural hearing loss (ISSHL). The German ISSHL guideline recommends high-dose steroids for primary therapy of ISSHL, without evidence from randomized controlled trials (RCTs). The rationale for the treatment of ISSHL using high dose steroids is only based on retrospective cohort studies.This article describes the planning and initiation of a multicenter, national, randomized, controlled clinical trial entitled Efficacy and safety of high dose glucocorticosteroid treatment for idiopathic sudden sensorineural hearing loss - a three-armed, randomized, triple-blind, multicenter trial (HODOKORT). This clinical trial aims to compare standard dose with two types of high-dose steroids for primary systemic therapy with respect to their efficacy in improving hearing, and thus communication ability, in patients with idiopathic sudden sensorineural hearing loss.This study is funded by the "Clinical Trials with High Patient Relevance" research program in the health research framework of the German Federal Ministry of Education and Research. It is one of two studies by the German Study Center of Clinical Trials of the German Society of Otorhinolaryngology, Head and Neck Surgery (DSZ-HNO). Planning and initiation was done in cooperation with the DSZ-HNO, the Coordination Center of Clinical Trials of the Martin-Luther-University Halle-Wittenberg, and the Study Center of the University Hospital Freiburg.

  18. Primary Hepatic Lymphoma: A Retrospective, Multicenter Rare Cancer Network Study

    PubMed Central

    Ugurluer, Gamze; Miller, Robert C.; Li, Yexiong; Thariat, Juliette; Ghadjar, Pirus; Schick, Ulrike; Ozsahin, Mahmut

    2016-01-01

    Primary hepatic lymphoma (PHL) is a rare malignancy. We aimed to assess the clinical profile, outcome and prognostic factors in PHL through the Rare Cancer Network (RCN). A retrospective analysis of 41 patients was performed. Median age was 62 years (range, 23-86 years) with a male-to-female ratio of 1.9:1.0. Abdominal pain or discomfort was the most common presenting symptom. Regarding B-symptoms, 19.5% of patients had fever, 17.1% weight loss, and 9.8% night sweats. The most common radiological presentation was multiple lesions. Liver function tests were elevated in 56.1% of patients. The most common histopathological diagnosis was diffuse large B-cell lymphoma (65.9%). Most of the patients received Chop-like (cyclophosphamide, doxorubicin, vincristine, and prednisone) regimens; 4 patients received radiotherapy (dose range, 30.6-40.0 Gy). Median survival was 163 months, and 5- and 10-year overall survival rates were 77 and 59%, respectively. The 5- and 10-year disease-free and lymphoma-specific survival rates were 69, 56, 87 and 70%, respectively. Multivariate analysis revealed that fever, weight loss, and normal hemoglobin level were the independent factors influencing the outcome. In this retrospective multicenter RCN study, patients with PHL had a relatively better prognosis than that reported elsewhere. Multicenter prospective studies are still warranted to establish treatment guidelines, outcome, and prognostic factors. PMID:27746888

  19. Research and operational applications in multi-center ensemble forecasting

    NASA Astrophysics Data System (ADS)

    Zhu, Y.; Toth, Z.

    2009-05-01

    The North American Ensemble Forecast System (NAEFS) was built up in 2004 by the Meteorological Service of Canada (MSC), the National Meteorological Service of Mexico (NMSM), and the US National Weather Service (NWS) as an operational multi-center ensemble forecast system. Currently it combines the 20-member MSC and NWS ensembles to form a joint ensemble of 40 members twice a day. The joint ensemble forecast, after bias correction and statistical downscaling, is used to generate a suite of products for CONUS, North America and for other regions of the globe. The THORPEX Interactive Grand Global Ensemble (TIGGE) project has been established a few years ago to collect operational global ensemble forecasts from world centers, and distribute to the scientific community, to encourage research leading to the acceleration of improvements in the skill and utility of high impact weather forecasts. TIGGE research is expected to advise the development of the operational NAEFS system and eventually the two projects are expected to converge into a single operational system, the Global Interactive Forecast System (GIFS). This presentation will review recent developments, the current status, and plans related to the TIGGE research and NAEFS operational multi-center ensemble projects.

  20. Diarrhoea in general practice: when should a Clostridium difficile infection be considered? Results of a nested case-control study.

    PubMed

    Hensgens, M P M; Dekkers, O M; Demeulemeester, A; Buiting, A G M; Bloembergen, P; van Benthem, B H B; Le Cessie, S; Kuijper, E J

    2014-12-01

    Clostridium difficile infections (CDIs) are frequent in hospitals, but also seem to increase in the community. Here, we aim to determine the incidence of CDI in general practice and to evaluate current testing algorithms for CDI. Three Dutch laboratories tested all unformed faeces (12,714) for C. difficile when diagnostic testing (for any enteric pathogen) was requested by a general practitioner (GP). Additionally, a nested case-control study was initiated, including 152 CDI patients and 304 age and sex-matched controls. Patients were compared using weighted multivariable logistic regression. One hundred and ninety-four samples (1.5%) were positive for C. difficile (incidence 0.67/10,000 patient years). This incidence was comparable to that of Salmonella spp. Compared with diarrhoeal controls, CDI was associated with more severe complaints, underlying diseases, antibiotic use and prior hospitalization. In our study, GPs requested a test for C. difficile in 7% of the stool samples, thereby detecting 40% of all CDIs. Dutch national recommendations advise testing for C. difficile when prior antibiotic use or hospitalization is present (18% of samples). If these recommendations were followed, 61% of all CDIs would have been detected. In conclusion, C. difficile is relatively frequent in general practice. Currently, testing for C. difficile is rare and only 40% of CDI in general practice is detected. Following recommendations that are based on traditional risk factors for CDI, would improve detection of CDI.

  1. Pseudomonas aeruginosa and Periodontal Pathogens in the Oral Cavity and Lungs of Cystic Fibrosis Patients: a Case-Control Study.

    PubMed

    Rivas Caldas, Rocio; Le Gall, Florence; Revert, Krista; Rault, Gilles; Virmaux, Michèle; Gouriou, Stephanie; Héry-Arnaud, Geneviève; Barbier, Georges; Boisramé, Sylvie

    2015-06-01

    Cystic fibrosis (CF) is the most frequent lethal genetic disease in the Caucasian population. Lung destruction is the principal cause of death by chronic Pseudomonas aeruginosa colonization. There is a high prevalence of oropharyngeal anaerobic bacteria in sputum of CF patients. This study was carried out due to the lack of results comparing subgingival periodontal pathogenic bacteria between the oral cavity and lungs in patients with CF in relation with P. aeruginosa presence. Our first goal was to detect P. aeruginosa in oral and sputum samples by culture and molecular methods and to determine clonality of isolates. In addition, subgingival periodontal anaerobic bacteria were searched for in sputum. A cross-sectional pilot case-control study was conducted in the CF Reference Center in Roscoff, France. Ten CF patients with a ΔF508 homozygous mutation (5 chronically colonized [CC] and 5 not colonized [NC]) were enrolled. P. aeruginosa was detected in saliva, sputum, and subgingival plaque samples by real-time quantitative PCR (qPCR). Subsequently, periodontal bacteria were also detected and quantified in subgingival plaque and sputum samples by qPCR. In CC patients, P. aeruginosa was recovered in saliva and subgingival plaque samples. Sixteen P. aeruginosa strains were isolated in saliva and sputum from this group and compared by pulsed-field gel electrophoresis (PFGE). Subgingival periodontal anaerobic bacteria were found in sputum samples. A lower diversity of these species was recovered in the CC patients than in the NC patients. The presence of the same P. aeruginosa clonal types in saliva and sputum samples underlines that the oral cavity is a possible reservoir for lung infection. PMID:25854483

  2. ALS Multicenter Cohort Study of Oxidative Stress (ALS COSMOS): study methodology, recruitment, and baseline demographic and disease characteristics.

    PubMed

    Mitsumoto, Hiroshi; Factor-Litvak, Pam; Andrews, Howard; Goetz, Raymond R; Andrews, Leslie; Rabkin, Judith G; McElhiney, Martin; Nieves, Jeri; Santella, Regina M; Murphy, Jennifer; Hupf, Jonathan; Singleton, Jess; Merle, David; Kilty, Mary; Heitzman, Daragh; Bedlack, Richard S; Miller, Robert G; Katz, Jonathan S; Forshew, Dallas; Barohn, Richard J; Sorenson, Eric J; Oskarsson, Bjorn; Fernandes Filho, J Americo M; Kasarskis, Edward J; Lomen-Hoerth, Catherine; Mozaffar, Tahseen; Rollins, Yvonne D; Nations, Sharon P; Swenson, Andrea J; Shefner, Jeremy M; Andrews, Jinsy A; Koczon-Jaremko, Boguslawa A

    2014-06-01

    Abstract In a multicenter study of newly diagnosed ALS patients without a reported family history of ALS, we are prospectively investigating whether markers of oxidative stress (OS) are associated with disease progression. Methods utilize an extensive structured telephone interview ascertaining environmental, lifestyle, dietary and psychological risk factors associated with OS. Detailed assessments were performed at baseline and at 3-6 month intervals during the ensuing 30 months. Our biorepository includes DNA, plasma, urine, and skin. Three hundred and fifty-five patients were recruited. Subjects were enrolled over a 36-month period at 16 sites. To meet the target number of subjects, the recruitment period was prolonged and additional sites were included. Results showed that demographic and disease characteristics were similar between 477 eligible/non-enrolled and enrolled patients, the only difference being type of health insurance among enrolled patients. Sites were divided into three groups by the number of enrolled subjects. Comparing these three groups, the Columbia site had fewer 'definite ALS' diagnoses. This is the first prospective, interdisciplinary, in-depth, multicenter epidemiological investigation of OS related to ALS progression and has been accomplished by an aggressive recruitment process. The baseline demographic and disease features of the study sample are now fully characterized.

  3. Prediction of accrual closure date in multi-center clinical trials with discrete-time Poisson process models

    PubMed Central

    Tang, Gong; Kong, Yuan; Chang, Chung-Chou Ho; Kong, Lan; Costantino, Joseph P.

    2016-01-01

    In a phase III multi-center cancer clinical trial or large public health studies, sample size is predetermined to achieve desired power and study participants are enrolled from tens or hundreds of participating institutions. As the accrual is closing to the target size, the coordinating data center needs to project the accrual closure date based on the observed accrual pattern and notify the participating sites several weeks in advance. In the past, projections were simply based on some crude assessment and conservative measures were incorporated in order to achieve the target accrual size. This approach often resulted in excessive accrual size and subsequently unnecessary financial burden on the study sponsors. Here we proposed a discrete-time Poisson process-based method to estimate the accrual rate at time of projection and subsequently the trial closure date. To ensure that target size would be reached with high confidence, we also proposed a conservative method for the closure date projection. The proposed method was illustrated through the analysis of the accrual data of NSABP trial B-38. The results showed that application of proposed method could help to save considerable amount of expenditure in patient management without compromising the accrual goal in multi-center clinical trials. PMID:22411544

  4. ALS Multicenter Cohort Study of Oxidative Stress (ALS COSMOS): The study methodology, recruitment, and baseline demographic and disease characteristics

    PubMed Central

    Mitsumoto, Hiroshi; Factor-Litvak, Pam; Andrews, Howard; Goetz, Raymond R.; Andrews, Leslie; Rabkin, Judith G.; McElhiney, Martin; Nieves, Jeri; Santella, Regina M.; Murphy, Jennifer; Hupf, Jonathan; Singleton, Jess; Merle, David; Kilty, Mary; Heitzman, Daragh; Bedlack, Richard S.; Miller, Robert G; Katz, Jonathan S.; Forshew, Dallas; Barohn, Richard J.; Sorenson, Eric J.; Oskarsson, Bjorn; Filho, J Americo M. Fernandes; Kasarskis, Edward J.; Lomen-Hoerth, Catherine; Mozaffar, Tahseen; Rollins, Yvonne D.; Nations, Sharon P.; Swenson, Andrea J.; Shefner, Jeremy M.; Andrews, Jinsy A.; Koczon-Jaremko, Boguslawa A.

    2015-01-01

    Objective In a multicenter study of newly diagnosed ALS patients without a reported family history of ALS, we are prospectively investigating whether markers of oxidative stress (OS) are associated with disease progression. Methods An extensive structured telephone interview ascertained environmental, lifestyle, dietary and psychological risk factors associated with OS. Detailed assessments were performed at baseline and at 3 to 6 month intervals during the ensuing 30 months. Our biorepository includes DNA, plasma, urine, and skin. Results 355 patients were recruited. Subjects were enrolled over a 36 month-period at 16 sites. To meet the target number of subjects, the recruitment period was prolonged and additional sites were included. Demographic and disease characteristics were similar between 477 eligible/non-enrolled and enrolled patients, with the only difference being type of health insurance among enrolled patients. Sites were divided into 3 groups by the number of enrolled subjects. Comparing these 3 groups, the Columbia site had fewer “definite ALS” diagnoses. Conclusion This is the first prospective, interdisciplinary, in-depth, multicenter epidemiological investigation of OS related to ALS progression and was accomplished by an aggressive recruitment process. The baseline demographic and disease features of the study sample are now fully characterized. PMID:24564738

  5. Bayes and empirical Bayes methods for reduced rank regression models in matched case-control studies

    PubMed Central

    Zhou, Qin; Lan, Qing; Rothman, Nathaniel; Langseth, Hilde; Engel, Lawrence S.

    2015-01-01

    Summary 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 non-trivial 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 polychlorinflated biphenyls in relation to the etiology of non-Hodgkin’s lymphoma. PMID:26575519

  6. High rate of inducible clindamycin resistance in Staphylococcus aureus isolates--a multicenter study in Tokyo, Japan.

    PubMed

    Shoji, Kensuke; Shinjoh, Masayoshi; Horikoshi, Yuho; Tang, Julian; Watanabe, Yasushi; Sugita, Kayoko; Tame, Tomoyuki; Iwata, Satoshi; Miyairi, Isao; Saitoh, Akihiko

    2015-02-01

    The resistance of Staphylococcus aureus (S. aureus) to antibiotics is an increasing problem. Clindamycin has been used as empiric therapy for the rising incidence of community-acquired methicillin-resistant S. aureus (MRSA). As such, the local rate of inducible resistance against clindamycin is an important consideration. This multicenter study was conducted to identify the incidence of inducible clindamycin resistance of S. aureus isolates in Tokyo, the most populous city in Japan. A total of 2408 adult and pediatric samples were collected from a university hospital and two pediatric hospitals between January 2011 and December 2011. Among the 2341 samples analyzed, the incidence of inducible clindamycin resistance in erythromycin-resistant and clindamycin-susceptible/intermediate isolates was found to be 91% (n = 585), a figure much higher compared to most reports from other countries. In conclusion, we found a very high rate of inducible clindamycin resistance in macrolide-resistant S. aureus isolates in our geographic area.

  7. Is Alpha-1 Antichymotrypsin Gene Polymorphism a Risk Factor for Primary Intracerebral Hemorrhage? A Case-Control Study and Meta-Analysis

    PubMed Central

    Hu, Xin; Li, Yunke; Li, Hao; Fang, Yuan; Liu, Ming; You, Chao

    2015-01-01

    Background Alpha-1 antichymotrypsin (ACT) signal peptide A/T polymorphism has been suggested to play a role in various brain diseases with arterial wall pathology. We conducted a case-control study and a meta-analysis to evaluate the association between this polymorphism and risk of primary intracerebral hemorrhage. Material/Methods A total of 188 patients and 200 age- and sex-matched healthy controls were enrolled in our case-control study. The ACT polymorphism was genotyped by PCR-LDR. Further meta-analysis was conducted by searching literature from PUBMED, EMBASE, and Chinese National Knowledge Infrastructure databases until December 2014, then combining data using STATA10.0. Results Similar genotype distribution was detected between PICH patients and healthy controls (p=0.523). Further analysis based on hypertension and location of hemorrhage did not observe significant association. Multiple logistic regression analysis also failed to identify ACT polymorphism as an independent risk factor for PICH. With regard to meta-analysis, a total of 6 case-control studies including 932 PICH patients and 1140 controls were enrolled. Pooled ORs failed to detect a significant association of ACT signal peptide A/T polymorphism with PICH (dominant model: OR=1.03, 95%CI=0.72–1.46; recessive model: OR=1.08, 95%CI=0.88–1.32). Subgroup analysis based on hypertension revealed no association in hypertensive PICH or in normotensive PICH. Conclusions Our case-control study in a Chinese population did not detect a significant association between ACT signal peptide A/T polymorphism and PICH. Moreover, meta-analysis combining data from relevant studies failed to provide evidence for the association. Further well-designed studies with larger sample sizes are warranted to verify our findings. PMID:26210716

  8. Do early skin care practices alter the risk of atopic dermatitis? A case-control study.

    PubMed

    Rendell, Marla E; Baig-Lewis, Shahana F; Berry, Trista M; Denny, Melissa E; Simpson, Brenda M; Brown, Peter A; Simpson, Eric L

    2011-01-01

    The rise in atopic dermatitis prevalence observed in industrialized countries is unexplained. We hypothesized that certain skin care practices early in life may increase the risk for developing atopic dermatitis. Our case-control study could not identify any one practice that increased the odds of developing atopic dermatitis, but it revealed that regular lotion use was very common in infants who later develop atopic dermatitis.

  9. Study design in evidence-based surgery: What is the role of case-control studies?

    PubMed Central

    Cao, Amy M; Cox, Michael R; Eslick, Guy D

    2016-01-01

    Randomized controlled trials (RCTs) are the gold standard in terms of study design, however, in the surgical setting conducting RCTs can often be unethical or logistically impossible. Case-control studies should become the major study design used in surgical research when RCTs are unable to be conducted and definitely replacing case series which offer little insight into surgical outcomes and disease processes. PMID:27019801

  10. Multicenter Study of Brain Volume Abnormalities in Children and Adolescent-Onset Psychosis

    PubMed Central

    Reig, Santiago; Parellada, Mara; Castro-Fornieles, Josefina; Janssen, Joost; Moreno, Dolores; Baeza, Inmaculada; Bargalló, Nuria; González-Pinto, Ana; Graell, Montserrat; Ortuño, Felipe; Otero, Soraya; Arango, Celso; Desco, Manuel

    2011-01-01

    The goal of the study is to determine the extent of structural brain abnormalities in a multicenter sample of children and adolescents with a recent-onset first episode of psychosis (FEP), compared with a sample of healthy controls. Total brain and lobar volumes and those of gray matter (GM), white matter, and cerebrospinal fluid (CSF) were measured in 92 patients with a FEP and in 94 controls, matched for age, gender, and years of education. Male patients (n = 64) showed several significant differences when compared with controls (n = 61). GM volume in male patients was reduced in the whole brain and in frontal and parietal lobes compared with controls. Total CSF volume and frontal, temporal, and right parietal CSF volumes were also increased in male patients. Within patients, those with a further diagnosis of “schizophrenia” or “other psychosis” showed a pattern similar to the group of all patients relative to controls. However, bipolar patients showed fewer differences relative to controls. In female patients, only the schizophrenia group showed differences relative to controls, in frontal CSF. GM deficit in male patients with a first episode correlated with negative symptoms. Our study suggests that at least part of the GM deficit in children and adolescent-onset schizophrenia and in other psychosis occurs before onset of the first positive symptoms and that, contrary to what has been shown in children-onset schizophrenia, frontal GM deficits are probably present from the first appearance of positive symptoms in children and adolescents. PMID:20478821

  11. Drug induced immune haemolytic anaemia in the Berlin Case-Control Surveillance Study.

    PubMed

    Garbe, Edeltraut; Andersohn, Frank; Bronder, Elisabeth; Klimpel, Andreas; Thomae, Michael; Schrezenmeier, Hubert; Hildebrandt, Martin; Späth-Schwalbe, Ernst; Grüneisen, Andreas; Mayer, Beate; Salama, Abdulgabar; Kurtal, Hanife

    2011-09-01

    Drug-induced immune haemolytic anaemia is a rare but serious condition. This study investigated the possibility of drug aetiology of immune haemolytic anaemia (IHA) in 134 patients with new onset of IHA who were identified in the Berlin Case-Control Surveillance Study between 2000 and 2009. Single drugs related to IHA in three or more patients and assessed more than once as a certain or probable cause of IHA in a standardized causality assessment included diclofenac, fludarabine, oxaliplatin, ceftriaxone and piperacillin. In a case-control study including all 124 IHA cases developed in outpatient care and 731 controls, significantly increased odds ratios (OR) were observed for beta-lactam antibiotics (OR=8·8; 95% confidence interval [CI] 3·2-25·2), cotrimoxazole (OR=6·5; CI 1·1-37·9), ciprofloxacin (OR=6·9, CI 1·3-38·5), fludarabine (OR=22·2; CI: 2·8-454·5) and lorazepam (OR=5·3; CI: 1·2-21·2). Excluding new onset cases with a chronic IHA disease course, an increased risk became also apparent for diclofenac with an OR of 3·1 (CI 1·3-7·0). This is the first case-control study investigating drugs as risk factors for IHA. It corroborates an increased risk for several drugs that have been implicated as a cause of IHA in the standardized causality assessment of individual cases. PMID:21749359

  12. Risk factors for neural tube defects in Riyadh City, Saudi Arabia: Case-control study

    PubMed Central

    Murshid, Waleed R; Mohamed, Ashry Gad; Ignacio, Lena C; de Jesus, Julie E; Baabbad, Rubana; El Bushra, Hassan M

    2014-01-01

    Both genetic and non-genetic environmental factors are involved in the etiology of neural tube defects (NTD) which affect 0.5-2/1000 pregnancies worldwide. This study aimed to explore the risk factors for the development of NTD in Saudi population, and highlight identifiable and preventable causes. Similar studies are scarce in similar populations ofthe Arabian Peninsula and North Africa. This is an unmatched concurrent case-control study including NTD cases born at King Khalid University Hospital, Riyadh during a 4-year period (2002-2006). The case-control study included 25 cases and 125 controls (case: control ratio of 1:5). Years of formal education, employment, household environment (including availability of air conditioning) and rate of parental consanguinity did not differ between mothers of cases and controls. Significantly higher proportion of mothers of cases had history of stillbirth compared to control mothers (16% vs 4.1%, P=0.02). Also family history of hydrocephalus and congenital anomalies were more prevalent in cases than controls (P values=0.0000 and 0.003, respectively). There was significant protective effect of periconceptional folic acid consumption both prior to conception (OR 0.02, 95% CI 0.00-0.07) and during the first 6 weeks of conception (OR 0.13, 95% CI 0.04-0.39). Further research, including a larger cohort, is required to enable ascertainment of gene-nutrient and gene environment interactions associated with NTD in Saudi Arabia. PMID:27493405

  13. Prevalence of Toxoplasma infection in veterinary laboratory sciences students comparing to ordinary people: a case-control study.

    PubMed

    Sadaghian, Mohammad; Jafari, Rasool

    2016-09-01

    Toxoplasma gondii causes the foremost widespread protozoan infection with a broad variety of host range, which consists of regarding of almost all warm-blooded vertebrates. There are some opinions concerning the probable occupational influence on infections to Toxoplasma in veterinary services personnel. The present study aimed to examine influence of studying in veterinary laboratory sciences as a risk factor on the prevalence rate of Toxoplasma infection in the students. In this case-control study, 80 blood samples were taken from veterinary laboratory sciences students (VLSS) as a case group and 80 blood samples from ordinary people of general population as a control group with the relatively same age, gender and health condition. Anti-Toxoplasma IgG levels in the serum samples were determined using quantitative ELISA method. According to the results, 27 (33.75 %) out of 80 samples of the cases group and also 29 (36.2 %) out of 80 samples of the control group were infected by the parasite. No statistically significant difference observed in the infection rate between the case and control groups (P = 0.740, OR 0.931; 95 % CI 0.61, 1.421). The mean serum antibody concentration in infected subjects of case and control groups showed no statistically significant difference (P = 0.618, t = 0.502). Normality of the data was assumed using Kolmogorov-Smirnov test (P = 0.806, Z = 0.641). Based on the results, in veterinary laboratory science students, toxoplasmosis is not related to their career and also the subjects of this group as the other people have the same risk to infect by this protozoan parasite. PMID:27605781

  14. Forming a Research Question from a Multi-Center Database

    PubMed Central

    Likosky, Donald S.

    2009-01-01

    Abstract: It is not uncommon for individuals to ask biostatisiticians and epidemiologists to assist them with a research project. Often the request is in the shape of statistical analyses. However, most of these requests are nothing more than missed opportunities. This manuscript focuses on the reasons underlying such a statement. Most individuals might say that the most important aspect of a study is its conclusion. Many who would disagree with this sentiment and would feel that the most important aspect of a study rather is the question it intends to address. If this question is not articulated sufficiently, any additional information stemming from the study will most likely be irrelevant. Herein, some principles for formulating (successfully) a question from a multi-center database will be described. PMID:19361039

  15. Effect of Latent Myofascial Trigger Points on Strength Measurements of the Upper Trapezius: A Case-Controlled Trial

    PubMed Central

    Anshul

    2011-01-01

    ABSTRACT Purpose: The purpose of this article was to determine whether strength is altered in the upper trapezius in the presence of latent myofascial trigger points (MTrP). Methods: This study was case controlled and used convenience sampling. The sample recruited was homogeneous with respect to age, sex, height, and body mass. Participants were assessed for the presence of latent MTrP in the upper trapezius and placed into two groups: an experimental group that had latent MTrP in the upper trapezius and a control group that did not. Eighteen women (mean age 21.4 y, SD 1.89; mean height 156.9 cm, SD 4.03; and mean body mass 51.7 kg, SD 5.84) made up the experimental group, and 19 women (mean age 20.3 y, SD 1.86; mean height 158.6 cm, SD 3.14; and mean body mass 53.2 kg, SD 5.17) made up the control group. We obtained strength measurements of the non-dominant arm using a handheld dynamometer and compared them between the two groups. Results: The difference in the strength measurements between the two groups was not statistically significant (p=0.59). Conclusions: The presence of latent MTrPs may not affect the strength of the upper trapezius. PMID:22942517

  16. RISK FACTORS FOR SLOW GAIT SPEED: A NESTED CASE-CONTROL SECONDARY ANALYSIS OF THE MEXICAN HEALTH AND AGING STUDY

    PubMed Central

    Pérez-Zepeda, M.U.; González-Chavero, J.G.; Salinas-Martinez, R.; Gutiérrez-Robledo, L.M.

    2016-01-01

    Background Physical performance tests play a major role in the geriatric assessment. In particular, gait speed has shown to be useful for predicting adverse outcomes. However, risk factors for slow gait speed (slowness) are not clearly described. Objectives To determine risk factors associated with slowness in Mexican older adults. Design A two-step process was adopted for exploring the antecedent risk factors of slow gait speed. First, the cut-off values for gait speed were determined in a representative sample of Mexican older adults. Then, antecedent risk factors of slow gait speed (defined using the identified cut-points) were explored in a nested, cohort case-control study. Setting, participants One representative sample of a cross-sectional survey for the first step and the Mexican Health and Aging Study (a cohort characterized by a 10-year follow-up). Measurements A 4-meter usual gait speed test was conducted. Lowest gender and height-stratified groups were considered as defining slow gait speed. Sociodemographic characteristics, comorbidities, psychological and health-care related variables were explored to find those associated with the subsequent development of slow gait speed. Unadjusted and adjusted logistic regression models were performed. Results In the final model, age, diabetes, hypertension, and history of fractures were associated with the development of slow gait speed. Conclusions Early identification of subjects at risk of developing slow gait speed may halt the path to disability due to the robust association of this physical performance test with functional decline. PMID:26889463

  17. Association between the OGG1 Ser326Cys Polymorphism and Cancer Risk: Evidence from 152 Case-Control Studies.

    PubMed

    Zou, Hua; Li, Qing; Xia, Wei; Liu, Yong; Wei, Xi; Wang, Dong

    2016-01-01

    Although it has been suggested that the 8-oxoguanine DNA glycosylase (OGG1) gene Ser326Cys polymorphism may be a risk factor for cancer, the conclusions from previous studies are inconsistent. Thus, we conducted an updated meta-analysis to estimate the effect of OGG1 variant genotypes on cancer susceptibility. We searched the PubMed for all eligible studies published in English for the period ending September 2014. We found the association between OGG1 Ser326Cys polymorphism and cancer susceptibility based on 152 case-control studies in different genetic model comparisons (dominant model: OR = 1.053, P = 0.018; recessive model: OR = 1.108, P < 0.001; homozygote: OR = 1.135, P < 0.001; additive model: OR = 1.059, P < 0.001). However, the results from the subgroup analyses based on types of cancer, health population as controls or studies with relatively large sample size did not support the conclusion. Although the overall results of this meta-analysis showed a positive association between OGG1 variant genotypes and cancer susceptibility, the subgroup analyses by cancer type, sample size, and source of controls presented inconsistent results. Therefore, the current evidence from the meta-analysis did not support the hypothesis of OGG1 Ser326Cys polymorphism as a risk factor of cancer. PMID:27390603

  18. Association of Smoking With Semen Quality and µ-Calpain Level in Normospermia: A Case-Control Study

    PubMed Central

    Ashtary-Larky, Damoon; Ghaffari, Mohammad Ali; Noorbehbahani, Mozhgan; Alipour, Meysam

    2016-01-01

    Objective: Calpains are a family of Ca2+ dependent proteases. There is some evidence that calpains involved in fusion process that occurs between spermatozoa and the oocyte. The current study aimed to investigate the association of smoking with semen quality and µ-calpain level. Materials and methods: This case-control study was conducted on 117 normospermia males between June 2013 and march 2014 in Jahad Laboratory in ahvaz, Iran. The semen samples were collected from male smokers (n = 50) and non-smokers (n = 67). We divided these participants as light, moderate, or heavy smokers based on their cigarettes per day (CPD). ELISA assays were used to measure µ-calpain concentration. All semen samples were analyzed according to World Health Organization guidelines. Results: The analysis of semen showed the volume, concentration, motility and morphology of semen were significantly lower among the smoker men than the non-smoker men. Also this significant difference was observed based on the number (light, moderate and heavy smokers) and duration (short term and long term smoker) of smoking. Although, showed no significant difference between µ-calpain of smoker men and non-smoker men. CPD showed negatively correlation with semen volume, concentration, motility and morphology of sperm. Conclusion: Sperm quality was negatively correlated with CPD and duration of smoking. However, there is no significant correlation between smoking and µ-calpain concentration. PMID:27385969

  19. Lack of Significant Effects of Chlamydia trachomatis Infection on Cervical Adenocarcinoma Risk: Nested Case-Control Study

    PubMed Central

    Smelov, Vitaly; Gheit, Tarik; Sundström, Karin; Ploner, Alexander; McKay-Chopin, Sandrine; Eklund, Carina; Tommasino, Massimo; Dillner, Joakim

    2016-01-01

    Background A role of Chlamydia trachomatis in HPV-induced cervical carcinogenesis has been reported for cervical cancer but studies on cervical adenocarcinoma are limited. Methods A total of 1,553 cervical smears taken up to 26 years before diagnosis in a large population-based nested case-control study of cervical adenocarcinoma (AC, 132 cases with matched controls), and adenocarcinoma in situ (AIS, 159 cases with matched controls) were tested for C. trachomatis and HPV DNA by a type-specific PCR bead-based multiplex genotyping (TS-MPG) assay. Results Only 1.7% of samples were positive for C. trachomatis, with no significant differences between AC/AIS cases and controls. HPV-positivity was detected in 49.3% of C. trachomatis-negative and 65.4% C. trachomatis-positive samples, respectively. Conclusions A large prospective study did not find any risk for cervical adenocarcinoma and/or AIS conferred by C. trachomatis infection. Impact C. trachomatis appears not to be involved in cervical adenocarcinomas. PMID:27227411

  20. Association between the OGG1 Ser326Cys Polymorphism and Cancer Risk: Evidence from 152 Case-Control Studies

    PubMed Central

    Zou, Hua; Li, Qing; Xia, Wei; Liu, Yong; Wei, Xi; Wang, Dong

    2016-01-01

    Although it has been suggested that the 8-oxoguanine DNA glycosylase (OGG1) gene Ser326Cys polymorphism may be a risk factor for cancer, the conclusions from previous studies are inconsistent. Thus, we conducted an updated meta-analysis to estimate the effect of OGG1 variant genotypes on cancer susceptibility. We searched the PubMed for all eligible studies published in English for the period ending September 2014. We found the association between OGG1 Ser326Cys polymorphism and cancer susceptibility based on 152 case-control studies in different genetic model comparisons (dominant model: OR = 1.053, P = 0.018; recessive model: OR = 1.108, P < 0.001; homozygote: OR = 1.135, P < 0.001; additive model: OR = 1.059, P < 0.001). However, the results from the subgroup analyses based on types of cancer, health population as controls or studies with relatively large sample size did not support the conclusion. Although the overall results of this meta-analysis showed a positive association between OGG1 variant genotypes and cancer susceptibility, the subgroup analyses by cancer type, sample size, and source of controls presented inconsistent results. Therefore, the current evidence from the meta-analysis did not support the hypothesis of OGG1 Ser326Cys polymorphism as a risk factor of cancer. PMID:27390603

  1. Oral Lymphoma Prevalence in Iranian Population: A Multicenter Retrospective Study

    PubMed Central

    Akbari, Mohammad Esmaeil; Bastani, Zahra; Mokhtari, Sepideh; Atarbashi Moghadam, Saede

    2015-01-01

    Background: Oral lymphoma is the second most common malignancy of the head and neck region after malignant epithelial tumors. Objectives: Considering the lack of a multicenter study on the frequency of oral lymphoma in Iran, this study aimed to assess the relative frequency of oral lymphomas in Iran during a 6-year period. Materials and Methods: This multicenter, retrospective, cross-sectional study was conducted in two phases. In the first phase, cases of oral lymphoma registered in the cancer research center (CRC) of Shahid Beheshti university of medical sciences were extracted. The patient records and pathology reports of these patients were retrieved from the archives and age, sex and microscopic type site of the lesions were evaluated. Results: Oral lymphoma accounts for 1% of head and neck malignancies and 8% of all lymphomas. From 2003 to 2008, a total of 437 new cases of oral lymphomas had been registered in the CRC. Diffuse large B-cell lymphoma was found to be the most common form of oral lymphoma in the 6-year period with 240 (54.9%) registered cases. The majority of detected cases were in the 6th and 7th decades of life with a male to female ratio of 1:84. Tonsils were the most common site of occurrence of lymphoma in the oral cavity (77.8%). Conclusions: The age of onset, site of involvement, sex of patients, and histopathological subtype of oral lymphomas in the Iranian population were found to be similar to those of most other countries. PMID:26855724

  2. Multi-Center Electronic Structure Calculations for Plasma Equation of State

    SciTech Connect

    Wilson, B G; Johnson, D D; Alam, A

    2010-12-14

    We report on an approach for computing electronic structure utilizing solid-state multi-center scattering techniques, but generalized to finite temperatures to model plasmas. This approach has the advantage of handling mixtures at a fundamental level without the imposition of ad hoc continuum lowering models, and incorporates bonding and charge exchange, as well as multi-center effects in the calculation of the continuum density of states.

  3. Transmission Assessment Surveys (TAS) to Define Endpoints for Lymphatic Filariasis Mass Drug Administration: A Multicenter Evaluation

    PubMed Central

    Chu, Brian K.; Deming, Michael; Biritwum, Nana-Kwadwo; Bougma, Windtaré R.; Dorkenoo, Améyo M.; El-Setouhy, Maged; Fischer, Peter U.; Gass, Katherine; Gonzalez de Peña, Manuel; Mercado-Hernandez, Leda; Kyelem, Dominique; Lammie, Patrick J.; Flueckiger, Rebecca M.; Mwingira, Upendo J.; Noordin, Rahmah; Offei Owusu, Irene; Ottesen, Eric A.; Pavluck, Alexandre; Pilotte, Nils; Rao, Ramakrishna U.; Samarasekera, Dilhani; Schmaedick, Mark A.; Settinayake, Sunil; Simonsen, Paul E.; Supali, Taniawati; Taleo, Fasihah; Torres, Melissa; Weil, Gary J.; Won, Kimberly Y.

    2013-01-01

    Background Lymphatic filariasis (LF) is targeted for global elimination through treatment of entire at-risk populations with repeated annual mass drug administration (MDA). Essential for program success is defining and confirming the appropriate endpoint for MDA when transmission is presumed to have reached a level low enough that it cannot be sustained even in the absence of drug intervention. Guidelines advanced by WHO call for a transmission assessment survey (TAS) to determine if MDA can be stopped within an LF evaluation unit (EU) after at least five effective rounds of annual treatment. To test the value and practicality of these guidelines, a multicenter operational research trial was undertaken in 11 countries covering various geographic and epidemiological settings. Methodology The TAS was conducted twice in each EU with TAS-1 and TAS-2 approximately 24 months apart. Lot quality assurance sampling (LQAS) formed the basis of the TAS survey design but specific EU characteristics defined the survey site (school or community), eligible population (6–7 year olds or 1st–2nd graders), survey type (systematic or cluster-sampling), target sample size, and critical cutoff (a statistically powered threshold below which transmission is expected to be no longer sustainable). The primary diagnostic tools were the immunochromatographic (ICT) test for W. bancrofti EUs and the BmR1 test (Brugia Rapid or PanLF) for Brugia spp. EUs. Principal Findings/Conclusions In 10 of 11 EUs, the number of TAS-1 positive cases was below the critical cutoff, indicating that MDA could be stopped. The same results were found in the follow-up TAS-2, therefore, confirming the previous decision outcome. Sample sizes were highly sex and age-representative and closely matched the target value after factoring in estimates of non-participation. The TAS was determined to be a practical and effective evaluation tool for stopping MDA although its validity for longer-term post-MDA surveillance

  4. Laparoscopic versus open adhesiolysis for small bowel obstruction - a multicenter, prospective, randomized, controlled trial

    PubMed Central

    2014-01-01

    Background Laparoscopic adhesiolysis is emerging as an alternative for open surgery in adhesive small bowel obstruction. Retrospective studies suggest that laparoscopic approach shortens hospital stay and reduces complications in these patients. However, no prospective, randomized, controlled trials comparing laparoscopy to open surgery have been published. Methods/Design This is a multicenter, prospective, open label, randomized, controlled trial comparing laparoscopic adhesiolysis to open surgery in patients with computed-tomography diagnosed adhesive small bowel obstruction that is not resolving with conservative management. The primary study endpoint is the length of postoperative hospital stay in days. Sample size was estimated based on preliminary retrospective cohort, which suggested that 102 patients would provide 80% power to detect a difference of 2.5 days in the length of postoperative hospital stay with significance level of 0.05. Secondary endpoints include passage of stool, commencement of enteral nutrition, 30-day mortality, complications, postoperative pain, and the length of sick leave. Tertiary endpoints consist of the rate of ventral hernia and the recurrence of small bowel obstruction during long-term follow-up. Long-term follow-up by letter or telephone interview will take place at 1, 5, and 10 years. Discussion To the best of our knowledge, this trial is the first one aiming to provide level Ib evidence to assess the use of laparoscopy in the treatment of adhesive small bowel obstruction. Trial registration ClinicalTrials.gov identifier: NCT01867528. Date of registration May 26th 2013. PMID:25306234

  5. Case-control geographic clustering for residential histories accounting for risk factors and covariates

    PubMed Central

    2006-01-01

    Background Methods for analyzing space-time variation in risk in case-control studies typically ignore residential mobility. We develop an approach for analyzing case-control data for mobile individuals and apply it to study bladder cancer in 11 counties in southeastern Michigan. At this time data collection is incomplete and no inferences should be drawn – we analyze these data to demonstrate the novel methods. Global, local and focused clustering of residential histories for 219 cases and 437 controls is quantified using time-dependent nearest neighbor relationships. Business address histories for 268 industries that release known or suspected bladder cancer carcinogens are analyzed. A logistic model accounting for smoking, gender, age, race and education specifies the probability of being a case, and is incorporated into the cluster randomization procedures. Sensitivity of clustering to definition of the proximity metric is assessed for 1 to 75 k nearest neighbors. Results Global clustering is partly explained by the covariates but remains statistically significant at 12 of the 14 levels of k considered. After accounting for the covariates 26 Local clusters are found in Lapeer, Ingham, Oakland and Jackson counties, with the clusters in Ingham and Oakland counties appearing in 1950 and persisting to the present. Statistically significant focused clusters are found about the business address histories of 22 industries located in Oakland (19 clusters), Ingham (2) and Jackson (1) counties. Clusters in central and southeastern Oakland County appear in the 1930's and persist to the present day. Conclusion These methods provide a systematic approach for evaluating a series of increasingly realistic alternative hypotheses regarding the sources of excess risk. So long as selection of cases and controls is population-based and not geographically biased, these tools can provide insights into geographic risk factors that were not specifically assessed in the case-control

  6. Attributable risk in men in two French case-control studies on mesothelioma and asbestos.

    PubMed

    Lacourt, Aude; Rolland, Patrick; Gramond, Céline; Astoul, Philippe; Chamming's, Soizick; Ducamp, Stéphane; Frenay, Catherine; Galateau-Sallé, Françoise; Gilg Soit Ilg, Anabelle; Imbernon, Ellen; Le Stang, Nolwenn; Pairon, Jean Claude; Goldberg, Marcel; Iwatsubo, Yuriko; Salmi, Louis-Rachid; Brochard, Patrick

    2010-11-01

    Pleural mesothelioma is a primary tumor of the pleura that is mainly due to asbestos exposure. To study the relationship between mesothelioma and occupational asbestos exposure in France, two case-control studies (A and B) were conducted. A substantial difference in the attributable risk in the population (AR(p)) was observed among men: 44.5% (95% CI: [32.6-56.4]) in study A and 83.2% (95% CI: [76.8-89.6]) in study B. As different exposure assessment expert methods were used, the main objective of this work was to re-estimate the AR(p) men in two case-control studies according to a common standardized exposure assessment by using a Job Exposure Matrix (JEM) and to assess the role of subjects' selection. The initial observed AR(p) difference was maintained: 36.3% (95% CI: [24.3-50.3]) in study A and 69.7% (95% CI: [51.7-83.2]) in study B. Further investigations highlighted the potential selection bias introduced in both studies, especially among controls. The AR(p) could be underestimated in study A and overestimated in study B. After weighting subjects according to distribution of socio-economic status in the general population for controls and according to distribution of socio-economic status of cases registered by the French National Mesothelioma Surveillance Program, re-estimated AR(p) values were 52.4% in study A and 70.2% in study B. These results provide additional information to describe the relationship between pleural mesothelioma and occupational asbestos exposure, but also confirm the importance of subjects' recruitment in case control studies, particularly control selection.

  7. Evaluating and comparing biomarkers with respect to the area under the receiver operating characteristics curve in two-phase case-control studies.

    PubMed

    Huang, Ying

    2016-07-01

    Two-phase sampling design, where biomarkers are subsampled from a phase-one cohort sample representative of the target population, has become the gold standard in biomarker evaluation. Many two-phase case-control studies involve biased sampling of cases and/or controls in the second phase. For example, controls are often frequency-matched to cases with respect to other covariates. Ignoring biased sampling of cases and/or controls can lead to biased inference regarding biomarkers' classification accuracy. Considering the problems of estimating and comparing the area under the receiver operating characteristics curve (AUC) for a binary disease outcome, the impact of biased sampling of cases and/or controls on inference and the strategy to efficiently account for the sampling scheme have not been well studied. In this project, we investigate the inverse-probability-weighted method to adjust for biased sampling in estimating and comparing AUC. Asymptotic properties of the estimator and its inference procedure are developed for both Bernoulli sampling and finite-population stratified sampling. In simulation studies, the weighted estimators provide valid inference for estimation and hypothesis testing, while the standard empirical estimators can generate invalid inference. We demonstrate the use of the analytical variance formula for optimizing sampling schemes in biomarker study design and the application of the proposed AUC estimators to examples in HIV vaccine research and prostate cancer research.

  8. Occupational risk factors and Alzheimer's disease: a case-control study

    SciTech Connect

    Shalat, S.L.; Seltzer, B.; Baker, E.L. Jr.

    1988-12-01

    A case-control study was conducted to assess occupational exposure to organic solvents and lead as risk factors for Alzheimer's disease. All case subjects were diagnosed at a Veterans Administration Hospital in Bedford, Massachusetts. Control subjects were selected from Massachusetts voter registration lists and matched by sex, year of birth, and town of residence. Information on occupational history was assessed by mailed questionnaire sent to the spouse or next of kin of the study subject. A total of 98 case and 162 control subjects were included in the matched analysis. No apparent association of increased risk of Alzheimer's disease was observed for ever having occupational exposure to organic solvents or lead.

  9. Does breast feeding provide protection against acute appendicitis? A case-control study.

    PubMed

    Alves, João Guilherme Bezerra; Figueiroa, José Natal; Barros, Isabela

    2008-10-01

    Breast feeding stimulates a more tolerant lymphoid tissue at the base of the appendix and this could provide protection against acute appendicitis. Two studies reported that children and adolescents with appendicitis were less likely to have been breast fed. In a case-control study of 200 children with histologically confirmed acute appendicitis matched by 200 siblings with the same sex and difference age - up to three-year-old - we found breast feeding in at least the first two months of life and for more than four months provides protection against acute appendicitis. These findings suggesting that breast feeding may possibly give protection against the development of appendicitis.

  10. Pancreas cancer, tobacco smoking and consumption of alcoholic beverages: a case-control study.

    PubMed

    Partanen, T J; Vainio, H U; Ojajärvi, I A; Kauppinen, T P

    1997-06-01

    A population-based case-control study investigated pancreas cancer in relation to consumption of alcoholic beverages, tobacco smoking and pancreatitis, utilizing historical proxy data for 662 decedent Finnish pancreas cancer cases and 1770 cancer controls. Tobacco smoking increased the risk, with an attributable case fraction of 0.27. The data are consistent with a joint effect of early and late stage carcinogens in tobacco smoke. Consumption of distilled beverages did not increase risk, but heavy drinking of wine or beer did. History of pancreatitis was a strong risk factor.

  11. Gastric cancer and coal mine dust exposure. A case-control study

    SciTech Connect

    Ames, R.G.

    1983-10-01

    Based on evidence that coal miners have elevated gastric cancer mortality rates, a case-control study was developed to assess the gastric cancer risk of coal mine dust exposure. Forty-six cases of US white male gastric cancer deaths from NIOSH coal miner cohorts were individually matched by age to controls. From these data we show that a statistically elevated gastric cancer risk exists for miners who have prolonged exposure to coal mine dust and prolonged exposure to cigarette smoke. Coal workers' pneumoconiosis, a disease defined in terms of coal dust deposition in the lungs, was not found to be a gastric cancer risk.

  12. Suicide by people in a community justice pathway: population-based nested case-control study.

    PubMed

    King, Carlene; Senior, Jane; Webb, Roger T; Millar, Tim; Piper, Mary; Pearsall, Alison; Humber, Naomi; Appleby, Louis; Shaw, Jenny

    2015-08-01

    The elevated risk of suicide in prison and after release is a well-recognised and serious problem. Despite this, evidence concerning community-based offenders' suicide risk is sparse. We conducted a population-based nested case-control study of all people in a community justice pathway in England and Wales. Our data show 13% of general population suicides were in community justice pathways before death. Suicide risks were highest among individuals receiving police cautions, and those having recent, or impending prosecution for sexual offences. Findings have implications for the training and practice of clinicians identifying and assessing suicidality, and offering support to those at elevated risk.

  13. [Risk factors for basal cell carcinoma. Case-control study in Cordoba].

    PubMed

    Ruiz Lascano, Alejandro; Kuznitzky, Raquel; Garay, Iliana; Ducasse, Cristina; Albertini, Ricardo

    2005-01-01

    Basal cell carcinoma is undoubtedly a complex disease. Its etiology is still unclear and despite its frequency, there is a paucity of data on its risk factors. We assessed potential risk factors for basal cell carcinoma in a population from Córdoba (Argentina). This case-control study involved 88 newly diagnosed cases and 88 controls, matched by age and sex. The following risk factors were significant in the multivariate analysis: skin type I-II-III, high recreational sun exposure after 20 years of age, high sun exposure for beach holidays and actinic keratosis.

  14. Human herpes virus-6 seroprevalence and leukaemias: a case-control study

    PubMed Central

    Gentile, G; Mele, A; Ragona, G; Faggioni, A; Zompetta, C; Tosti, M E; Visani, G; Castelli, G; Pulsoni, A; Monarca, B; Martino, P; Mandelli, F

    1999-01-01

    The relationships between acute myeloid leukaemia (AML), acute lymphocytic leukaemia (ALL), chronic myeloid leukaemia (CML) and refractory anaemia with excess of blasts (RAEB) and human herpes virus (HHV)-6 antibody level were investigated in a multicentre case-control study. An association between increased HHV-6 seropositivity and geometric mean titre ratio with AML was shown: P for trend = 0.022, adjusted odds ratio 1.20, 95% confidence interval 1.07–1.33 respectively. No association was found between HHV-6 and ALL, CML or RAEB. © 1999 Cancer Research Campaign PMID:10362124

  15. Meat intake, 'mate' drinking and renal cell cancer in Uruguay: a case-control study.

    PubMed Central

    De Stefani, E.; Fierro, L.; Mendilaharsu, M.; Ronco, A.; Larrinaga, M. T.; Balbi, J. C.; Alonso, S.; Deneo-Pellegrini, H.

    1998-01-01

    In the period January 1988-December 1995, a case-control study of diet and renal cell carcinoma (RCC) risk involving 121 cases and 243 hospitalized controls was carried out in Montevideo, Uruguay. After adjusting for major covariates, red meat intake was associated with a 3.4 increase in risk for the highest category of intake, with a significant dose-response pattern. Also, barbecued meat, protein and heterocyclic amine intakes were associated with significant increases in risk of RCC. The consumption of the beverage known as 'mate' (a ocal tea derived from the herb Ilex paraguariensis) was associated with an increased risk of 3.0 for heavy drinkers. PMID:9820187

  16. A FORTRAN program for stratified analysis of data from case-control studies.

    PubMed

    Koepsell, T D

    1983-04-01

    Stratification of study subjects by one or more covariates is a commonly accepted method for dealing with confounding and effect modification in epidemiologic case-control studies. A flexible FORTRAN program is described which facilitates simultaneous stratification by several covariates and which produces summary odds ratio estimates and chi-square statistics by the Mantel-Haenszel method. It also facilitates detection of effect modification by each covariate considered individually. Straightforward means are provided for the user to modify input data before analysis or to exclude certain subjects from analysis, simulating such capabilities in larger statistical packages.

  17. Evaluation of 16S rRNA Gene PCR Sensitivity and Specificity for Diagnosis of Prosthetic Joint Infection: a Prospective Multicenter Cross-Sectional Study

    PubMed Central

    Plouzeau, Chloé; Tande, Didier; Léger, Julie; Giraudeau, Bruno; Valentin, Anne Sophie; Jolivet-Gougeon, Anne; Vincent, Pascal; Corvec, Stéphane; Gibaud, Sophie; Juvin, Marie Emmanuelle; Héry-Arnaud, Genevieve; Lemarié, Carole; Kempf, Marie; Bret, Laurent; Quentin, Roland; Coffre, Carine; de Pinieux, Gonzague; Bernard, Louis; Burucoa, Christophe

    2014-01-01

    There is no standard method for the diagnosis of prosthetic joint infection (PJI). The contribution of 16S rRNA gene PCR sequencing on a routine basis remains to be defined. We performed a prospective multicenter study to assess the contributions of 16S rRNA gene assays in PJI diagnosis. Over a 2-year period, all patients suspected to have PJIs and a few uninfected patients undergoing primary arthroplasty (control group) were included. Five perioperative samples per patient were collected for culture and 16S rRNA gene PCR sequencing and one for histological examination. Three multicenter quality control assays were performed with both DNA extracts and crushed samples. The diagnosis of PJI was based on clinical, bacteriological, and histological criteria, according to Infectious Diseases Society of America guidelines. A molecular diagnosis was modeled on the bacteriological criterion (≥1 positive sample for strict pathogens and ≥2 for commensal skin flora). Molecular data were analyzed according to the diagnosis of PJI. Between December 2010 and March 2012, 264 suspected cases of PJI and 35 control cases were included. PJI was confirmed in 215/264 suspected cases, 192 (89%) with a bacteriological criterion. The PJIs were monomicrobial (163 cases [85%]; staphylococci, n = 108; streptococci, n = 22; Gram-negative bacilli, n = 16; anaerobes, n = 13; others, n = 4) or polymicrobial (29 cases [15%]). The molecular diagnosis was positive in 151/215 confirmed cases of PJI (143 cases with bacteriological PJI documentation and 8 treated cases without bacteriological documentation) and in 2/49 cases without confirmed PJI (sensitivity, 73.3%; specificity, 95.5%). The 16S rRNA gene PCR assay showed a lack of sensitivity in the diagnosis of PJI on a multicenter routine basis. PMID:25056331

  18. Evaluation of 16S rRNA gene PCR sensitivity and specificity for diagnosis of prosthetic joint infection: a prospective multicenter cross-sectional study.

    PubMed

    Bémer, Pascale; Plouzeau, Chloé; Tande, Didier; Léger, Julie; Giraudeau, Bruno; Valentin, Anne Sophie; Jolivet-Gougeon, Anne; Vincent, Pascal; Corvec, Stéphane; Gibaud, Sophie; Juvin, Marie Emmanuelle; Héry-Arnaud, Genevieve; Lemarié, Carole; Kempf, Marie; Bret, Laurent; Quentin, Roland; Coffre, Carine; de Pinieux, Gonzague; Bernard, Louis; Burucoa, Christophe

    2014-10-01

    There is no standard method for the diagnosis of prosthetic joint infection (PJI). The contribution of 16S rRNA gene PCR sequencing on a routine basis remains to be defined. We performed a prospective multicenter study to assess the contributions of 16S rRNA gene assays in PJI diagnosis. Over a 2-year period, all patients suspected to have PJIs and a few uninfected patients undergoing primary arthroplasty (control group) were included. Five perioperative samples per patient were collected for culture and 16S rRNA gene PCR sequencing and one for histological examination. Three multicenter quality control assays were performed with both DNA extracts and crushed samples. The diagnosis of PJI was based on clinical, bacteriological, and histological criteria, according to Infectious Diseases Society of America guidelines. A molecular diagnosis was modeled on the bacteriological criterion (≥ 1 positive sample for strict pathogens and ≥ 2 for commensal skin flora). Molecular data were analyzed according to the diagnosis of PJI. Between December 2010 and March 2012, 264 suspected cases of PJI and 35 control cases were included. PJI was confirmed in 215/264 suspected cases, 192 (89%) with a bacteriological criterion. The PJIs were monomicrobial (163 cases [85%]; staphylococci, n = 108; streptococci, n = 22; Gram-negative bacilli, n = 16; anaerobes, n = 13; others, n = 4) or polymicrobial (29 cases [15%]). The molecular diagnosis was positive in 151/215 confirmed cases of PJI (143 cases with bacteriological PJI documentation and 8 treated cases without bacteriological documentation) and in 2/49 cases without confirmed PJI (sensitivity, 73.3%; specificity, 95.5%). The 16S rRNA gene PCR assay showed a lack of sensitivity in the diagnosis of PJI on a multicenter routine basis.

  19. Evaluation of 16S rRNA gene PCR sensitivity and specificity for diagnosis of prosthetic joint infection: a prospective multicenter cross-sectional study.

    PubMed

    Bémer, Pascale; Plouzeau, Chloé; Tande, Didier; Léger, Julie; Giraudeau, Bruno; Valentin, Anne Sophie; Jolivet-Gougeon, Anne; Vincent, Pascal; Corvec, Stéphane; Gibaud, Sophie; Juvin, Marie Emmanuelle; Héry-Arnaud, Genevieve; Lemarié, Carole; Kempf, Marie; Bret, Laurent; Quentin, Roland; Coffre, Carine; de Pinieux, Gonzague; Bernard, Louis; Burucoa, Christophe

    2014-10-01

    There is no standard method for the diagnosis of prosthetic joint infection (PJI). The contribution of 16S rRNA gene PCR sequencing on a routine basis remains to be defined. We performed a prospective multicenter study to assess the contributions of 16S rRNA gene assays in PJI diagnosis. Over a 2-year period, all patients suspected to have PJIs and a few uninfected patients undergoing primary arthroplasty (control group) were included. Five perioperative samples per patient were collected for culture and 16S rRNA gene PCR sequencing and one for histological examination. Three multicenter quality control assays were performed with both DNA extracts and crushed samples. The diagnosis of PJI was based on clinical, bacteriological, and histological criteria, according to Infectious Diseases Society of America guidelines. A molecular diagnosis was modeled on the bacteriological criterion (≥ 1 positive sample for strict pathogens and ≥ 2 for commensal skin flora). Molecular data were analyzed according to the diagnosis of PJI. Between December 2010 and March 2012, 264 suspected cases of PJI and 35 control cases were included. PJI was confirmed in 215/264 suspected cases, 192 (89%) with a bacteriological criterion. The PJIs were monomicrobial (163 cases [85%]; staphylococci, n = 108; streptococci, n = 22; Gram-negative bacilli, n = 16; anaerobes, n = 13; others, n = 4) or polymicrobial (29 cases [15%]). The molecular diagnosis was positive in 151/215 confirmed cases of PJI (143 cases with bacteriological PJI documentation and 8 treated cases without bacteriological documentation) and in 2/49 cases without confirmed PJI (sensitivity, 73.3%; specificity, 95.5%). The 16S rRNA gene PCR assay showed a lack of sensitivity in the diagnosis of PJI on a multicenter routine basis. PMID:25056331

  20. Ki-67 Expression in Sclerosing Adenosis and Adjacent Normal Breast Terminal Ductal Lobular Units: A Nested Case-Control Study from the Mayo Benign Breast Disease Cohort

    PubMed Central

    Nassar, Aziza; Hoskin, Tanya L.; Stallings-Mann, Melody L.; Degnim, Amy C.; Radisky, Derek C.; Frost, Marlene H.; Vierkant, Robert A.; Hartmann, Lynn C.; Visscher, Daniel W.

    2015-01-01

    Purpose Sclerosing adenosis (SA) increases risk for invasive breast cancer (BC) 2.1 times relative to that in the general population. Here, we sought to evaluate whether the proliferation marker Ki-67 stratifies risk among women with SA. Methods A nested case-control sample of patients with SA was obtained from the Mayo Clinic Benign Breast Disease Cohort. Ki-67 expression was evaluated in SA lesions and in the adjacent normal terminal duct lobular units (TDLU) in women who did (cases, n =133) or did not (controls, n =239) develop BC. Ki67 was scored by intensity and number of positively stained cells per one high-power field (magnification, ×40) (40×HPF) for both SA and normal TDLU. Associations of Ki-67 expression with case-control status were assessed using conditional logistic regression. Results Higher Ki-67 expression was significantly associated with case-control status in both SA (P=.03) and normal background TDLU (P=.006). For the SA lesion, >2 average positively stained cells/40×HPF showed an adjusted odds ratio (OR) of 1.9 (95% CI, 1.1–3.4) compared to samples with an average of ≤2 positively stained cells. For background TDLU, lobules with >2 but ≤6 average positively stained cells showed an adjusted OR of 1.3 to 1.5, whereas those with an average of >6 positively stained cells had an OR of 2.4 (95% CI, 1.1–5.3) compared to those with an average of <2 positively stained cells. Conclusions Among women with SA, increased Ki-67 expression in either the SA lesion or the normal background TDLU carried an approximately 2-fold increased odds of subsequent BC as compared to lower Ki-67 expression. PMID:25863475

  1. Human leukocyte antigen polymorphisms in Italian primary biliary cirrhosis: a multicenter study of 664 patients and 1992 healthy controls

    PubMed Central

    Invernizzi, Pietro; Selmi, Carlo; Poli, Francesca; Frison, Sara; Floreani, Annarosa; Alvaro, Domenico; Almasio, Piero; Rosina, Floriano; Marzioni, Marco; Fabris, Luca; Muratori, Luigi; Qi, Lihong; Seldin, Michael F.; Gershwin, M. Eric; Podda, Mauro

    2008-01-01

    Genetic factors are critical in determining susceptibility to primary biliary cirrhosis (PBC), but there has not been a clear association with human leukocyte antigen (HLA) genes. We performed a multi-center case-control study and analyzed HLA class II DRB1 associations using a large cohort of 664 well-defined cases of PBC and 1,992 controls of Italian ancestry. Importantly, healthy controls were rigorously matched not only by age and gender, but also for the geographical origin of the proband four grandparents (Northern, Central, and Southern Italy). Following correction for multiple testing, DRB1*08 (Odds Ratio–OR, 3.3; 95% Confidence Interval–CI, 2.4−4.5) and DRB1*02 (OR 0.9; 95% CI 0.8−1.2) were significantly associated with PBC while alleles DRB1*11 (OR 0.4; 95% CI 0.3−0.4) and DRB1*13 (OR 0.7; 95% CI 0.6−0.9) were protective. When subjects were stratified according to their grandparental geographical origin, only the associations with DRB1*08 and DRB1*11 were common to all three areas. Associated DRB1 alleles were found only in a minority of patients while an additive genetic model is supported by the gene dosage effect for DRB1*11 allele and the interaction of DRB1*11,*13, and *08. Lastly, no significant associations were detected between specific DRB1 alleles and relevant clinical features represented by the presence of cirrhosis or serum autoantibodies. In conclusion, we confirm the role for HLA to determine PBC susceptibility and suggest that the effect of HLA is limited to patient subgroups. We suggest that a large whole-genome approach is required to identify further genetic elements contributing to the loss of tolerance in this disease. PMID:19003916

  2. A multicenter study of the early detection of synaptic dysfunction in Mild Cognitive Impairment using Magnetoencephalography-derived functional connectivity.

    PubMed

    Maestú, Fernando; Peña, Jose-Maria; Garcés, Pilar; González, Santiago; Bajo, Ricardo; Bagic, Anto; Cuesta, Pablo; Funke, Michael; Mäkelä, Jyrki P; Menasalvas, Ernestina; Nakamura, Akinori; Parkkonen, Lauri; López, Maria E; Del Pozo, Francisco; Sudre, Gustavo; Zamrini, Edward; Pekkonen, Eero; Henson, Richard N; Becker, James T

    2015-01-01

    Synaptic disruption is an early pathological sign of the neurodegeneration of Dementia of the Alzheimer's type (DAT). The changes in network synchronization are evident in patients with Mild Cognitive Impairment (MCI) at the group level, but there are very few Magnetoencephalography (MEG) studies regarding discrimination at the individual level. In an international multicenter study, we used MEG and functional connectivity metrics to discriminate MCI from normal aging at the individual person level. A labeled sample of features (links) that distinguished MCI patients from controls in a training dataset was used to classify MCI subjects in two testing datasets from four other MEG centers. We identified a pattern of neuronal hypersynchronization in MCI, in which the features that best discriminated MCI were fronto-parietal and interhemispheric links. The hypersynchronization pattern found in the MCI patients was stable across the five different centers, and may be considered an early sign of synaptic disruption and a possible preclinical biomarker for MCI/DAT.

  3. Data on serologic inflammatory biomarkers assessed using multiplex assays and host characteristics in the Multicenter AIDS Cohort Study (MACS).

    PubMed

    McKay, Heather S; Bream, Jay H; Margolick, Joseph B; Martínez-Maza, Otoniel; Magpantay, Larry I; Phair, John P; Rinaldo, Charles R; Abraham, Alison G; Jacobson, Lisa P

    2016-12-01

    This article contains data on the associations between fixed and modifiable host characteristics and twenty-three biomarkers of inflammation and immune activation measured longitudinally in a cohort of 250 HIV-uninfected men from the Multicenter AIDS Cohort Study (1984-2009) after adjusting for age, study site, and blood draw time of day using generalized gamma regression. This article also presents associations between each biomarker and each host characteristic in a sample restricted to 2001-2009. These data are supplemental to our original research article entitled "Host factors associated with serologic inflammatory markers assessed using multiplex assays" (McKay, S. Heather, Bream, H. Jay, Margolick, B. Joseph, Martínez-Maza, Otoniel, Phair, P. John, Rinaldo, R. Charles, Abraham, G. Alison, L.P. Jacobson, 2016) [1]. PMID:27668272

  4. Data on serologic inflammatory biomarkers assessed using multiplex assays and host characteristics in the Multicenter AIDS Cohort Study (MACS).

    PubMed

    McKay, Heather S; Bream, Jay H; Margolick, Joseph B; Martínez-Maza, Otoniel; Magpantay, Larry I; Phair, John P; Rinaldo, Charles R; Abraham, Alison G; Jacobson, Lisa P

    2016-12-01

    This article contains data on the associations between fixed and modifiable host characteristics and twenty-three biomarkers of inflammation and immune activation measured longitudinally in a cohort of 250 HIV-uninfected men from the Multicenter AIDS Cohort Study (1984-2009) after adjusting for age, study site, and blood draw time of day using generalized gamma regression. This article also presents associations between each biomarker and each host characteristic in a sample restricted to 2001-2009. These data are supplemental to our original research article entitled "Host factors associated with serologic inflammatory markers assessed using multiplex assays" (McKay, S. Heather, Bream, H. Jay, Margolick, B. Joseph, Martínez-Maza, Otoniel, Phair, P. John, Rinaldo, R. Charles, Abraham, G. Alison, L.P. Jacobson, 2016) [1].

  5. Circulating levels of 25-hydroxyvitamin D and risk of breast cancer: a nested case-control study

    PubMed Central

    2013-01-01

    Introduction Experimental evidence suggests a protective role for circulating 25-hydroxyvitamin D (25(OH)D) in breast cancer development, but the results of epidemiological studies have been inconsistent. Methods We conducted a case-control study nested within two prospective cohorts, the New York University Women's Health Study and the Northern Sweden Mammary Screening Cohort. Blood samples were collected at enrollment, and women were followed up for breast cancer ascertainment. In total, 1,585 incident breast cancer cases were individually-matched to 2,940 controls. Of these subjects, 678 cases and 1,208 controls contributed two repeat blood samples, at least one year apart. Circulating levels of 25(OH)D were measured, and multivariate odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using conditional logistic regression. Results No association was observed between circulating levels of 25(OH)D and overall breast cancer risk (multivariate-adjusted model OR = 0.94, 95% CI = 0.76-1.16 for the highest vs. lowest quintile, ptrend = 0.30). The temporal reliability of 25(OH)D measured in repeat blood samples was high (intraclass correlation coefficients for season-adjusted 25(OH)D > 0.70). An inverse association between 25(OH)D levels and breast cancer risk was observed among women who were ≤ 45 years of age (ORQ5-Q1 = 0.48, 95% CI = 0.30-0.79, ptrend = 0.01) or premenopausal at enrollment (ORQ5-Q1 = 0.67, 95% CI = 0.48-0.92, ptrend = 0.03). Conclusions Circulating 25(OH)D levels were not associated with breast cancer risk overall, although we could not exclude the possibility of a protective effect in younger women. Recommendations regarding vitamin D supplementation should be based on considerations other than breast cancer prevention. PMID:23442740

  6. 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

  7. Indoor air risk factors for schoolchildren's health in Portuguese homes: Results from a case-control survey.

    PubMed

    Madureira, Joana; Paciência, Inês; Cavaleiro-Rufo, João; Fernandes, Eduardo de Oliveira

    2016-01-01

    Allergic diseases have been on the rise in many countries over the past few decades and indoor exposure may be a possible cause. An overall investigation of children's health status and residential indoor air pollutants known or suspected to affect respiratory health was conducted in the homes of primary schoolchildren during winter in Porto, Portugal. In a case-control study (30 case children with asthma and 38 controls) and over a 1-wk monitoring period, air sample collection was conducted in children's bedrooms for the analysis of 12 volatile organic compounds (VOC), aldehydes, particulate matter (PM)2.5, PM10, bacteria, and fungi. Home exposures to indoor pollutants are similar for children with and without asthma, except for d-limonene. For both groups, most VOC were present at low concentrations (median < 5 µg/m(3)) and below the respective World Health Organization (WHO) guidelines. Concentrations of PM2.5, PM10, and bacteria were frequently higher than WHO/reference values (80, 25, and 60% of all studied dwellings, respectively). Concentrations of carbon dioxide (CO2) exceeding 1000 ppm were encountered in 60% of the homes. Although this study does not provide evidence of causative factors for asthmatic status, the postulation that poor indoor air quality in homes heightens the risk of allergic symptoms development among children is conceivable. PMID:27644344

  8. Environmental Risk Factors and Amyotrophic Lateral Sclerosis (ALS): A Case-Control Study of ALS in Michigan

    PubMed Central

    Yu, Yu; Su, Feng-Chiao; Callaghan, Brian C.; Goutman, Stephen A.; Batterman, Stuart A.; Feldman, Eva L.

    2014-01-01

    An interim report of a case-control study was conducted to explore the role of environmental factors in the development of amyotrophic lateral sclerosis (ALS). Sixty-six cases and 66 age- and gender-matched controls were recruited. Detailed information regarding residence history, occupational history, smoking, physical activity, and other factors was obtained using questionnaires. The association of ALS with potential risk factors, including smoking, physical activity and chemical exposure, was investigated using conditional logistic regression models. As compared to controls, a greater number of our randomly selected ALS patients reported exposure to fertilizers to treat private yards and gardens and occupational exposure to pesticides in the last 30 years than our randomly selected control cases. Smoking, occupational exposures to metals, dust/fibers/fumes/gas and radiation, and physical activity were not associated with ALS when comparing the randomly selected ALS patients to the control subjects. To further explore and confirm results, exposures over several time frames, including 0–10 and 10–30 years earlier, were considered, and analyses were stratified by age and gender. Pesticide and fertilizer exposure were both significantly associated with ALS in the randomly selected ALS patients. While study results need to be interpreted cautiously given the small sample size and the lack of direct exposure measures, these results suggest that environmental and particularly residential exposure factors warrant close attention in studies examining risk factors of ALS. PMID:24979055

  9. Is prenatal childbirth preparation effective in decreasing adverse maternal and neonatal response to labor? A nested case-control study.

    PubMed

    Kim, Hyun Hee; Nava-Ocampo, Alejandro A; Kim, Sun Kyung; Kim, Seo Hui; Kim, Yun Ju; Han, Jung Yeol; Ahn, Hyun Kyong; Ryu, Hyun Mee; Yang, Jae Hyug; Kim, Moon Young

    2008-04-01

    Sophrology, based on a combination of Western relaxation therapy and Eastern yoga and meditation might decrease maternal stress during labor. This study aimed to evaluate whether prenatal sophrologic childbirth preparation may decrease maternal and neonatal adverse response associated with delivery. In a nested case-control study, 69 nulliparous, singleton pregnant women who underwent an educational course of sophrologic childbirth preparation were compared to 69 nulliparous, singleton, age- and gestational age-matched pregnant women who did not receive any childbirth preparation. All babies were vaginally delivered. Groups were not different (P > 0.05) in the number of neonates born with meconium-stained amniotic fluid as well as in the number of babies with Apgar score < or = 7 at 1 and 5 minutes after birth. Duration of labor was not different between groups. The number of women requiring oxytocin and delivering babies with low pH blood levels tended to be lower in the group undergoing sophrologic childbirth preparation, i.e. 58.0% vs 72.5% (P = 0.07) and 1.4% vs 10.9% (P = 0.06), respectively. In conclusion, we were unable to confirm that prenatal sophrologic childbirth preparation has a definitive role in decreasing adverse maternal and fetal response to pain or in shortening labor. Prospective cohort studies with a larger sample size or randomized trials may help to clarify this gap.

  10. Blood fatty acid patterns are associated with prostate cancer risk in a prospective nested case-control study

    PubMed Central

    Yang, Meng; Ayuningtyas, Azalea; Kenfield, Stacey A.; Sesso, Howard D.; Campos, Hannia; Ma, Jing; Stampfer1, Meir J.; Chavarro, Jorge E.

    2016-01-01

    Background Circulating fatty acids are highly correlated with each other and analyzing fatty acid patterns could better capture their interactions and their relation to prostate cancer. We aimed to assess the associations between data-derived blood fatty acid patterns and prostate cancer risk. Methods We conducted a nested case-control study in the Physicians’ Health Study. Fatty acids levels were measured in whole blood samples of 476 cases and their matched controls by age and smoking status. Fatty acid patterns were identified using principal component analysis. Conditional logistic regression was used to estimate odds ratio (OR) and 95% confidence interval (CI). Results Two patterns explaining 40.9% of total variation in blood fatty acid levels were identified. Pattern 1, which mainly reflects polyunsaturated fatty acid metabolism, was suggestively positively related to prostate cancer risk (ORquintile 5 vs. quintile 1=1.37, 95%CI=0.91–2.05, Ptrend=0.07). Pattern 2, which largely reflects de novo lipogenesis, was significantly associated with higher prostate cancer risk (ORquintile5 vs quintile1=1.63, 95%CI=1.04–2.55, Ptrend=0.02). This association was similar across tumor stage, grade, clinical aggressiveness categories and follow-up time. Conclusion The two patterns of fatty acids we identified were consistent with known interactions between fatty acid intake and metabolism. A pattern suggestive of higher activity in the de novo lipogenesis pathway was related to higher risk of prostate cancer. PMID:27488836

  11. Emotional processing and its relationship to chronic low back pain: results from a case-control study.

    PubMed

    Esteves, Jorge E; Wheatley, Laura; Mayall, Clare; Abbey, Hilary

    2013-12-01

    Chronic low back pain (CLBP) is a common, yet challenging condition for both patients and clinicians. Several studies have demonstrated a strong association between CLBP and psychological factors such as anxiety, fear-avoidance, self-efficacy, catastrophizing and depression. These factors are closely linked with emotional states; however, it is unknown whether CLBP patients process their emotions differently from asymptomatic individuals. The aim of this case-control study was to investigate the relationship between CLBP and emotional processing. A sample of 110 participants comprising of 55 patients with chronic back pain and 55 individuals without a history of CLBP were assessed using the Emotional Processing Scale (EPS-25). The EPS-25 generates an overall score, and also scores pertaining to five individual emotional processing factors--avoidance, suppression, unregulated emotion, impoverished emotional experience and signs of unprocessed emotion. Chronic back pain patients scored significantly higher in the overall EPS-25 score (p < 0.001) with an effect size of 0.33. In addition, there were significant differences in four factors--impoverished emotional experience, unregulated emotion, unprocessed emotion, and suppression, with effect sizes ranging from 0.20 to 0.44. The results suggest that dysfunctional emotional processing, particularly with regard to the suppression of emotions, is associated with CLBP. Clinicians should critically consider the role of emotional processing in their patients' evaluation and management. Future research using a prospective cohort should assess the role of emotional processing as a predictor in the development of chronic back pain.

  12. Outlining a Population “at Risk” of Parkinson's Disease: Evidence from a Case-Control Study

    PubMed Central

    Schirinzi, Tommaso; Martella, Giuseppina; D'Elia, Alessio; Di Lazzaro, Giulia; Imbriani, Paola; Madeo, Graziella; Monaco, Leonardo; Maltese, Marta

    2016-01-01

    The multifactorial pathogenesis of Parkinson's Disease (PD) requires a careful identification of populations “at risk” of developing the disease. In this case-control study we analyzed a large Italian population, in an attempt to outline general criteria to define a population “at risk” of PD. We enrolled 300 PD patients and 300 controls, gender and age matched, from the same urban geographical area. All subjects were interviewed on demographics, family history of PD, occupational and environmental toxicants exposure, smoking status, and alcohol consumption. A sample of 65 patients and 65 controls also underwent serum dosing of iron, copper, mercury, and manganese by means of Inductively Coupled-Plasma-Mass-Spectrometry (ICP-MS). Positive family history, toxicants exposure, non-current-smoker, and alcohol nonconsumer status occurred as significant risk factors in our population. The number of concurring risk factors overlapping in the same subject impressively increased the overall risk. No significant differences were measured in the metal serum levels. Our findings indicate that combination of three to four concurrent PD-risk factors defines a condition “at risk” of PD. A simple stratification, based on these questionnaires, might be of help in identifying subjects suitable for neuroprotective strategies.

  13. Association of Hepatitis C Virus Infection with Type II Diabetes in Ethiopia: A Hospital-Based Case-Control Study

    PubMed Central

    Ali, Solomon; Abera, Solomon; Mihret, Adane; Abebe, Tamrat

    2012-01-01

    Background. Chronic hepatitis C virus (HCV) has become the global “epidemic” with an estimated 123 million people currently infected worldwide. As the same time diabetes is also rapidly emerging as a global health care problem that threatens to reach pandemic levels by 2030. Objective. To investigate the magnitude of HCV infection in type II diabetes as compared to controls. Methodology. A case control study design was conducted at Jimma University Specialized Hospital from May to June 2010. A total of 604 study subjects were included in this study. Sociodemographic and risk factor data were collected by questionnaire. From serum sample, HCVAb screening was done by rapid antibody screening test. Liver functioning tests and total cholesterol tests were done by Dr. Lange LP 800 spectrophotometer. Results. The prevalence of HCV in type II diabetes and nondiabetic controls was 9.9% and 3.3%, respectively. In multivariate analysis, HCV seropositives have high risk of developing diabetes as compared with seronegatives (AOR = 2.997, 95% CI: (1.08, 8.315)). Conclusion. In this study, we found a positive association between past HCV infection and type II diabetes. As we did not perform HCV RNA test, we could not assess the association with HCV viremia. PMID:23049551

  14. The relationship between computerized physician order entry and pediatric adverse drug events: a nested matched case-control study.

    PubMed

    Yu, Feliciano; Salas, Maribel; Kim, Young-Il; Menachemi, Nir

    2009-08-01

    This study assesses the impact of computerized physician order entry (CPOE) implementation in pediatric hospitals on reported adverse drug events. Using a nested matched case-control design; we linked CPOE implementation information from the health information management systems society analytics database with reported adverse drug event (ADE) from the national association of children's hospitals and related institutions case mix comparative data program. Differences were examined using univariate and multivariate conditional logistic regression analyses. Patients from CPOE hospitals were more frequently seen in larger hospitals have more co-morbidities than those from non-CPOE hospitals. When matched by admitting diagnosis, age, gender and race, ADE cases were associated with more reported co-morbidities, and were reported less frequently in hospitals with CPOE. Patients from hospitals without CPOE were 42% more likely to experience reportable ADE after adjusting for the presence of co-morbidities. In conclusion, we found significant beneficial associations between reportable ADE and CPOE adoption in a representative sample of pediatric hospitals.

  15. KSHV MicroRNA Sequence Analysis and KS Risk in an European AIDS-KS Case Control Study

    PubMed Central

    Marshall, Vickie; Martró, Elisa; Labo, Nazzarena; Ray, Alex; Wang, Dian; Mbisa, Georginia; Bagni, Rachel K.; Volfovsky, Natalia; Casabona, Jordi; Whitby, Denise

    2010-01-01

    Background We recently identified polymorphisms in KSHV encoded microRNA (miRNA) sequences from clinical subjects. Here, we examine whether any of these may contribute to KS risk in a European AIDS-KS case control study. Methods KSHV viral load in peripheral blood was determined by real-time quantitative PCR. Samples that had detectable viral loads were used to amplify the 2.8 kbp microRNA encoding region plus a 646 bp fragment of the K12/T0.7 gene. Additionally, we characterized an 840 bp fragment of the K1 gene to determine KSHV subtypes. Results KSHV viral DNA was detected in PBMC of 49.6% cases and 6.8% controls and viral loads tended to be higher in cases. Sequences from the miRNA encoding regions were conserved overall but distinct polymorphisms were detected some of which occurred in pri-miRNAs, pre-miRNAs or mature miRNAs. Conclusions Patients with Kaposi’s sarcoma were more likely to have detectable viral loads than controls without disease. Despite high conservation in KSHV miRNA encoded sequences, polymorphisms were observed including some that have been previously reported. Some polymorphisms could affect mature miRNA processing and appear to be associated with KS risk. PMID:20715927

  16. Dry eye disease and depression-anxiety-stress: A hospital-based case control study in Turkey

    PubMed Central

    Yilmaz, Ugur; Gokler, Mehmet Enes; Unsal, Alaettin

    2015-01-01

    Objective: The aim of the present study was to investigate the association between dry eye disease (DED) and psychosomatic conditions, such as depression, stress, and anxiety, and the distribution of associated risk factors. Methods: In this case control study, the sample consisted of 121 DED subjects and 242 control subjects. Each subjects was diagnosed as having DED or not by an ophthalmologist. Ocular Surface Disease Index and Depression Anxiety Stress Scales were administered to all subjects. Data were analysed using chi-square and Mann Whitney U tests as a univariate analysis and multiple logistic regression as a multivariate analysis. Results: Of 1,458 consecutive outpatients, clinically diagnosed DED was present in 121 individuals (8.3%). There was a significant relationship of family history of DED (OR, 1.43; 95% CI, 0.84-2.41), chronic disease history (OR, 2.84; 95% CI, 1.66-4.87), OSDI score (OR, 1.07; 95% CI, 1.97–4.06), depression (OR, 2.06; 95% CI, 1.30-3.27), anxiety (OR, 2.66; 95% CI, 1.67-4.23), and stress (OR, 2.33; 95% CI, 1.48-3.67) with DED. Conclusion: Individuals with depression, anxiety and stress are more likely to experience DED. In addition to confirming some well-known risk factors, this study has found new associations between DED and a family history of DED and the presence of stress. PMID:26150857

  17. Bayesian Analysis on Meta-analysis of Case-control Studies Accounting for Within-study Correlation

    PubMed Central

    Chen, Yong; Chu, Haitao; Luo, Sheng; Nie, Lei; Chen, Sining

    2013-01-01

    In retrospective studies, odds ratio is often used as the measure of association. Under independent beta prior assumption, the exact posterior distribution of odds ratio given a single 2 × 2 table has been derived in the literature. However, independence between risks within the same study may be an oversimplified assumption because cases and controls in the same study are likely to share some common factors and thus to be correlated. Furthermore, in a meta-analysis of case-control studies, investigators usually have multiple 2×2 tables. In this paper, we first extend the published results on a single 2×2 table to allow within study prior correlation while retaining the advantage of closed form posterior formula, and then extend the results to multiple 2 × 2 tables and regression setting. The hyperparameters, including within study correlation, are estimated via an empirical Bayes approach. The overall odds ratio and the exact posterior distribution of the study-specific odds ratio are inferred based on the estimated hyperparameters. We conduct simulation studies to verify our exact posterior distribution formulas and investigate the finite sample properties of the inference for the overall odds ratio. The results are illustrated through a twin study for genetic heritability and a meta-analysis for the association between the N-acetyltransferase 2 (NAT2) acetylation status and colorectal cancer. PMID:22143403

  18. Factors associated with colorectal cancer in the context of the Mediterranean diet: a case-control study.

    PubMed

    Grosso, Giuseppe; Biondi, Antonio; Galvano, Fabio; Mistretta, Antonio; Marventano, Stefano; Buscemi, Silvio; Drago, Filippo; Basile, Francesco

    2014-01-01

    Recent evidence demonstrates that increased adherence to the Mediterranean diet (MD) may prevent colorectal cancer (CRC). The aim of this study was to evaluate the association between health-related characteristics and CRC in the context of the MD. This was a case-control study conducted on a sample of 338 consecutive patients with a first diagnosis of CRC recruited in an urban facility in the city of Catania, southern Italy, and matched with 676 apparently healthy subjects without clinical symptoms or signs of any type of cancer. Data regarding sociodemographic, clinical, and lifestyle characteristics were collected, and adherence to the Mediterranean diet pattern was assessed using the MedDietScore. A significant association between a greater adherence to the MD and lower odds of having cancer (odds ratio = 0.46, 95% confidence interval: 0.28-0.75) was found. Also, smoking status, family history of CRC, obesity, diabetes, physical activity, and high intake of alcohol were significantly associated with CRC, but only among subjects less adherent to the MD. MD was associated with a less detrimental effects of several health-related characteristics associated with CRC, suggesting potential benefits of adherence to this dietary pattern with regards to CRC risk factors.

  19. A Community Outbreak of Cryptosporidiosis in Sydney Associated with a Public Swimming Facility: A Case-Control Study

    PubMed Central

    Mayne, Darren J.; Ressler, Kelly-Anne; Smith, Diane; Hockey, Gareth; Botham, Susan J.; Ferson, Mark J.

    2011-01-01

    In February, 2008, the South Eastern Sydney Illawarra Public Health Unit investigated an outbreak of cryptosporidiosis within the south east region of Sydney, Australia. Thirty-one cases with laboratory-confirmed cryptosporidiosis and 97 age- and geographically matched controls selected by random digit dialling were recruited into a case-control study and interviewed for infection risk factors. Cryptosporidiosis was associated with swimming at Facility A (matched odds ratio = 19.4, 95% confidence interval: 3.7–100.8) and exposure to household contacts with diarrhoea (matched odds ratio = 7.7, 95% confidence interval: 1.9–31.4) in multivariable conditional logistic regression models. A protective effect for any animal contact was also found (matched odds ratio = 0.2, 95% confidence interval: 0.1–0.7). Cryptosporidium hominis subtype IbA10G2 was identified in 8 of 11 diagnostic stool samples available for cases. This investigation reaffirms the importance of public swimming pools as potential sources of Cryptosporidium infection and ensuring their compliance with water-quality guidelines. The protective effect of animal contact may be suggestive of past exposure leading to immunity. PMID:22194741

  20. Outlining a Population “at Risk” of Parkinson's Disease: Evidence from a Case-Control Study

    PubMed Central

    Schirinzi, Tommaso; Martella, Giuseppina; D'Elia, Alessio; Di Lazzaro, Giulia; Imbriani, Paola; Madeo, Graziella; Monaco, Leonardo; Maltese, Marta

    2016-01-01

    The multifactorial pathogenesis of Parkinson's Disease (PD) requires a careful identification of populations “at risk” of developing the disease. In this case-control study we analyzed a large Italian population, in an attempt to outline general criteria to define a population “at risk” of PD. We enrolled 300 PD patients and 300 controls, gender and age matched, from the same urban geographical area. All subjects were interviewed on demographics, family history of PD, occupational and environmental toxicants exposure, smoking status, and alcohol consumption. A sample of 65 patients and 65 controls also underwent serum dosing of iron, copper, mercury, and manganese by means of Inductively Coupled-Plasma-Mass-Spectrometry (ICP-MS). Positive family history, toxicants exposure, non-current-smoker, and alcohol nonconsumer status occurred as significant risk factors in our population. The number of concurring risk factors overlapping in the same subject impressively increased the overall risk. No significant differences were measured in the metal serum levels. Our findings indicate that combination of three to four concurrent PD-risk factors defines a condition “at risk” of PD. A simple stratification, based on these questionnaires, might be of help in identifying subjects suitable for neuroprotective strategies. PMID:27651975

  1. Body Mass Index Is Associated With Mucosal Disease in Crohn’s: Results of a Case-Control Study

    PubMed Central

    Malik, Talha A.; Kaslow, Richard A.; Cofield, Stacey S.; Mannon, Peter J.

    2014-01-01

    Background Recent studies have suggested that increased body mass index (BMI) may have an adverse effect on treatment outcomes and natural history in Crohn’s disease (CD). We aimed to test the hypothesis that CD patients with higher BMI would be more likely than those with lower BMI to have persistent active mucosal disease. Methods We designed a case-control study. Sample population comprised CD patients with active disease at the beginning of observation. At the end of observation, cases had persistent active mucosal disease and controls had entered remission. With multivariable logistic regression models, we evaluated the effect of baseline BMI as a continuous variable and a categorical variable on persistent active mucosal disease. Results We analyzed data from 104 patients (36 cases and 68 controls). In a model containing BMI as a continuous variable, higher BMI was significantly associated with persistent active mucosal disease (odds ratio (OR) = 1.09 per unit increase; 95% confidence interval (CI), 1.02 - 1.17; P = 0.012). In a model containing BMI as a categorical variable, obese patients were 2.7 times more likely to have persistent active mucosal disease compared to non-obese patients (OR = 2.72; 95% CI, 1.00 - 7.35; P = 0.049). Conclusion Excessive weight measured both quantitatively as BMI and categorically as obesity in CD patients is associated with persistent active mucosal disease.

  2. Tobacco, alcohol, asbestos, and nickel in the etiology of cancer of the larynx: a case-control study

    SciTech Connect

    Burch, J.D.; Howe, G.R.; Miller, A.B.; Semenciw, R.

    1981-12-01

    A case-control study of laryngeal cancer was conducted in southern Ontario between 1977 and 1979 with 204 subjects with newly diagnosed cancer and 204 controls, individually matched by sex, age, and residence. Tobacco products and alcohol showed strong associations with cancer of the larynx for males, with relative risks (RR) for users of cigarettes, cigars or cigarillos, pipes, and alcohol of 6.1, 2.9, 1.6, and 5.2, respectively. The population attributable risk percent for males using tobacco products and alcohol together was estimated to be 94%. Cigarette smoking was also an important risk factor for females, although the small number of female pairs (20) precluded any meaningful detailed analysis of other possible risk factors. The RR for males for exposure to asbestos after the effects of cigarette smoking were controlled was 2.3, and the effects seemed restricted to cigarette smokers. The findings on asbestos were based on small numbers of cases and controls exposed and consequently were subject to large sampling errors. The estimate was consistent, however, with that from other studies and supported a causal role for asbestos exposure and cancer of the larynx. The RR for males for exposure to nickel was 0.9.

  3. A case-control study of non-fatal traffic accidents on hospital patients in Bangkok metropolis.

    PubMed

    Böhning, D; Na Ayutha, R S

    1997-01-01

    Morbidity and mortality from road traffic accidents in Bangkok metropolis is high with a trend strictly increasing in time, thus establishing one of the major public health problems and targets of the Kingdom of Thailand. An unmatched case-control study was undertaken to evaluate various risk patterns connected with the occurrence of traffic accidents. 350 cases were sampled from five major hospitals distributed over the Bangkok Metropolitan area and 350 controls were included from out-patients of Rajawithi hospital. The major interest in this case-control analysis is to estimate relative risk (through odds ratio) and measure statistical significance of association between road traffic accident and the following risk factors: the demographic risk factors are age (age between 15 and 19 years has odds ratio of 8.25 [1.01, 67.72]; age above 40 is baseline), marital status (single has odds ratio of 2.74 [1.26, 5.95]; baseline is not-single), sex (males have an odds ratio of 2.05 [0.51, 8.24], occupation (salespersons have an odds ratio of 4.27 [1.47, 12.46]; baseline are office workers); the driving related exposure factors type of vehicle (motorbikers have an odds ratio of 6.22 [2.82, 13.78]; baseline are other vehicle drivers), driving time per day (odds ratio 1.35 [0.88, 2.09]) and the number of accidents in the last three years (odds ratio of 4.36 [2.51, 7.58]); the behavioral factors one hour before driving such as the consumption of alcohol (odds ratio 3.01 [1.53, 5.94]; baseline in no alcohol) and the consumption of a lot of food (odds ratio of 0.07 [0.03, 0.16]; baseline is not eating a lot before driving). The odds ratios for traffic accident when being under allergic medication and the consumption of tranquilizer were not significant. The results are consistent with current results in traffic accident research and point to target groups for potential prevention programmes in traffic accident prevention. PMID:9499466

  4. Use of Hypoprothrombinemia-Inducing Cephalosporins and the Risk of Hemorrhagic Events: A Nationwide Nested Case-Control Study

    PubMed Central

    Shen, Li-Jiuan; Wu, Fe-Lin Lin; Tsay, Woei; Hung, Chien-Ching; Lin, Shu-Wen

    2016-01-01

    Objective Existing data regarding the risk of hemorrhagic events associated with exposure to hypoprothrombinemia-inducing cephalosporins are limited by the small sample size. This population-based study aimed to examine the association between exposure to hypoprothrombinemia-inducing cephalosporins and hemorrhagic events using National Health Insurance Research Database in Taiwan. Design A nationwide nested case-control study. Setting National Health Insurance Research database. Participants We conducted a nested case-control study within a cohort of 6191 patients who received hypoprothrombinemia-inducing cephalosporins and other antibiotics for more than 48 hours. Multivariable conditional logistic regressions were used to calculate the adjusted odds ratio (aOR) and 95% confidence interval (CI) for hemorrhagic events associated with exposure to hypoprothrombinemia-inducing cephalosporins (overall, cumulative dose measured as defined daily dose (DDD), and individual cephalosporins). Results Within the cohort, we identified 704 patients with hemorrhagic events and 2816 matched controls. Use of hypoprothrombinemia-inducing cephalosporins was associated with increased risk of hemorrhagic events (aOR, 1.71; 95% CI, 1.42–2.06), which increased with higher cumulative doses (<3 DDDs, aOR 1.62; 3–5 DDDs, aOR 1.78; and >5 DDDs, aOR 1.89). The aOR for individual cephalosporin was 2.88 (95% CI, 2.08–4.00), 1.35 (1.09–1.67) and 4.57 (2.63–7.95) for cefmetazole, flomoxef, and cefoperazone, respectively. Other risk factors included use of anticoagulants (aOR 2.08 [95% CI, 1.64–2.63]), liver failure (aOR 1.69 [1.30–2.18]), poor nutritional status (aOR 1.41 [1.15–1.73]), and history of hemorrhagic events (aOR 2.57 [1.94–3.41]) 6 months prior to the index date. Conclusions Use of hypoprothrombinemia-inducing cephalosporins increases risk of hemorrhagic events. Close watch for hemorrhagic events is recommended when prescribing these cephalosporins, especially in

  5. 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

  6. Does benzene cause multiple myeloma? An analysis of the published case-control literature

    SciTech Connect

    Bezabeh, S.; Engel, A.; Morris, C.B.; Lamm, S.H.

    1996-12-01

    Two case series and two epidemiological studies in the 1970s and 1980s suggested that benzene exposure might be a risk factor for multiple myeloma. An analysis has now been conducted of the published population-based and hospital-based case-control studies published through mid-1995 that permit examination of the relationship between multiple myeloma and benzene exposure or surrogates for benzene exposure. No increased association was found between multiple myeloma and benzene exposure or exposure to chemical groups that included benzene. The odds ratios from these analyses approximated 1.0. Exposures to petroleum products and employment in petroleum-related occupations did not appear to be risk factors for multiple myeloma. Cigarette smoking, as a surrogate of benzene exposure, was not found to be associated with multiple myeloma, while some studies of products of combustion described as {open_quotes}engine exhaust{close_quotes} did show a significant association with multiple myeloma. In toto, the population-based and hospital-based case-control literature indicated that benzene exposure was not a likely causal factor for multiple myeloma. 28 refs., 3 figs., 1 tab.

  7. A case-control study on risk factors for unintentional childhood poisoning in Tehran

    PubMed Central

    Mansori, Kamyar; Soori, Hamid; Farnaghi, Fariba; Khodakarim, Sohila; Mansouri hanis, Shiva; Khodadost, Mahmoud

    2016-01-01

    Background: Poisoning is a major public health problem and is one of the most frequent causes of emergency hospital admissions. The aim of this study was to identify the main risk factors for unintentional childhood poisoning in Tehran, Iran and to suggest possible causes and preventative measures. Methods: In this case-control study (case, n=140; control, n=280), two controls were selected for every case. Controls were matched by age, sex, and date of hospital attendance. All children and their guardians were then interviewed by the same person using a standard questionnaire that covered the demographic, behavioral, and risk factors associated with accidental poisonings. Results: The most common type of poisoning was related to narcotics (58.6%); and among the narcotics, methadone was the most prevalent poisoning agent (74.7%). Multivariate conditional logistic regression model revealed that addiction in the family (OR=14.6; 95% CI:6.2-34.6), previous poisoning (OR=7; 95% CI:2.4- 20.2), maternal occupation (OR=4; 95% CI:1.3- 12.3), and inaccessibility of poisoning products (OR=0.03; 95% CI:0.01- 0.12) were the main risk factors in unintentional childhood poisoning. Conclusion: Addiction in the family as a risk factor and inaccessibility of poisoning products as a protecting factor were recognized to have the highest correlation with the unintentional child poisoning. These two factors were considered as priorities in health education programs. PMID:27453885

  8. Snippets from the past: is Flint, Michigan, the birthplace of the case-control study?

    PubMed

    Morabia, Alfredo

    2013-12-15

    In the summer of 1924, an outbreak of scarlet fever occurred in Flint, Michigan. Unable to trace it to the usual causes, particularly fresh milk, the Michigan Department of Health used a novel approach to disentangle the enigma: The 116 cases of scarlet fever were compared with 117 "controls" selected from neighbors of the quarantined cases and from patients at the City Health Center who had been treated for ailments unrelated to scarlet fever. The extraordinary culprit was ice cream, which had a frequent/occasional/none consumption prevalence of 60%, 34%, and 6% among the cases and 24%, 51%, and 25% among the controls, respectively. The 1925 report reads, "Detailed epidemiological investigation, by means of case histories and control histories on well persons, confirmed early suspicions and established the fact that the epidemic was spread by ice cream" (Am J Hyg. 1925;5(5):669-681). This forgotten epidemiologic study is the oldest study using the case-control design to have been resurrected thus far. The case-control study design may have been conceived simultaneously, but independently and for different purposes, in England (Janet Lane-Claypon's 1926 report on the determinants of breast cancer) and the United States.

  9. A low-level asbestos exposure case-control epidemiology study

    SciTech Connect

    Ocasio-Alvarex, A.

    1988-01-01

    The potential for low levels of airborne asbestos exposure in public schools and in public and commercial buildings in the United States has generated concern due to the large population at risk and the definite human carcinogenicity of asbestos at high levels. To assist in the clarification of the risk associated with low level asbestos exposure and in the decision-making in asbestos management in schools and in other buildings, a case-control study was conducted to estimate the risk relationship between low levels of asbestos exposure and pulmonary cancer among Indiana public school teachers. A total of 236 lung cancer cases and 154 controls to be used in this case-control study were identified from a previous proportionate mortality rate study which had examined over 8,000 teachers' death certificates. The controls were selected from teachers who died of chronic bronchitis, emphysema or a chronic obstructive pulmonary disease. The teachers' work history and their potential for asbestos exposure, as well as the reliability of the information obtained on the presence or absence of asbestos, was determined to calculate the odds ratio.

  10. Leptospira Exposure and Patients with Liver Diseases: A Case-Control Seroprevalence Study

    PubMed Central

    Alvarado-Esquivel, Cosme; Sánchez-Anguiano, Luis Francisco; Hernández-Tinoco, Jesús; Ramos-Nevárez, Agar; Margarita Cerrillo-Soto, Sandra; Alberto Guido-Arreola, Carlos

    2016-01-01

    The seroepidemiology of Leptospira infection in patients suffering from liver disease has been poorly studied. Information about risk factors associated with infection in liver disease patients may help in the optimal planning of preventive measures. We sought to determine the association of Leptospira IgG seroprevalence and patients with liver diseases, and to determine the characteristics of the patients with Leptospira exposure. We performed a case-control study of 75 patients suffering from liver diseases and 150 age- and gender-matched control subjects. Diagnoses of liver disease included liver cirrhosis, steatosis, chronic hepatitis, acute hepatitis, and amoebic liver abscess. Sera of participants were analyzed for the presence of anti- Leptospira IgG antibodies using a commercially available enzyme immunoassay. Anti-Leptospira IgG antibodies were found in 17 (22.7%) of 75 patients and in 15 (10.0%) of 150 control subjects (OR = 2.32; 95% CI: 1.09-4.94; P=0.03). This is the first age- and gender-matched case control study about Leptospira seroprevalence in patients with liver diseases. Results indicate that Leptospira infection is associated with chronic and acute liver diseases. Results warrants for additional studies on the role of Leptospira exposure in chronic liver disease. PMID:27493589

  11. Snippets from the past: is Flint, Michigan, the birthplace of the case-control study?

    PubMed

    Morabia, Alfredo

    2013-12-15

    In the summer of 1924, an outbreak of scarlet fever occurred in Flint, Michigan. Unable to trace it to the usual causes, particularly fresh milk, the Michigan Department of Health used a novel approach to disentangle the enigma: The 116 cases of scarlet fever were compared with 117 "controls" selected from neighbors of the quarantined cases and from patients at the City Health Center who had been treated for ailments unrelated to scarlet fever. The extraordinary culprit was ice cream, which had a frequent/occasional/none consumption prevalence of 60%, 34%, and 6% among the cases and 24%, 51%, and 25% among the controls, respectively. The 1925 report reads, "Detailed epidemiological investigation, by means of case histories and control histories on well persons, confirmed early suspicions and established the fact that the epidemic was spread by ice cream" (Am J Hyg. 1925;5(5):669-681). This forgotten epidemiologic study is the oldest study using the case-control design to have been resurrected thus far. The case-control study design may have been conceived simultaneously, but independently and for different purposes, in England (Janet Lane-Claypon's 1926 report on the determinants of breast cancer) and the United States. PMID:24064743

  12. Leptospira Exposure and Patients with Liver Diseases: A Case-Control Seroprevalence Study.

    PubMed

    Alvarado-Esquivel, Cosme; Sánchez-Anguiano, Luis Francisco; Hernández-Tinoco, Jesús; Ramos-Nevárez, Agar; Margarita Cerrillo-Soto, Sandra; Alberto Guido-Arreola, Carlos

    2016-06-01

    The seroepidemiology of Leptospira infection in patients suffering from liver disease has been poorly studied. Information about risk factors associated with infection in liver disease patients may help in the optimal planning of preventive measures. We sought to determine the association of Leptospira IgG seroprevalence and patients with liver diseases, and to determine the characteristics of the patients with Leptospira exposure. We performed a case-control study of 75 patients suffering from liver diseases and 150 age- and gender-matched control subjects. Diagnoses of liver disease included liver cirrhosis, steatosis, chronic hepatitis, acute hepatitis, and amoebic liver abscess. Sera of participants were analyzed for the presence of anti- Leptospira IgG antibodies using a commercially available enzyme immunoassay. Anti-Leptospira IgG antibodies were found in 17 (22.7%) of 75 patients and in 15 (10.0%) of 150 control subjects (OR = 2.32; 95% CI: 1.09-4.94; P=0.03). This is the first age- and gender-matched case control study about Leptospira seroprevalence in patients with liver diseases. Results indicate that Leptospira infection is associated with chronic and acute liver diseases. Results warrants for additional studies on the role of Leptospira exposure in chronic liver disease. PMID:27493589

  13. A case-control study of infant, maternal and perinatal characteristics associated with deformational plagiocephaly.

    PubMed

    McKinney, Christy M; Cunningham, Michael L; Holt, Victoria L; Leroux, Brian; Starr, Jacqueline R

    2009-07-01

    Deformational plagiocephaly, an abnormal asymmetric flattening of infants' heads, is diagnosed in approximately 10% of infants. The prevalence of plagiocephaly has increased dramatically since 1992 when it was first recommended that infants be placed to sleep in a non-prone position to reduce the risk of sudden infant death syndrome. The authors conducted a case-control study to evaluate associations between plagiocephaly and perinatal characteristics. The authors assessed whether risk factors for plagiocephaly have changed since 1992. Cases were born 1987-2002 in Washington State and diagnosed with plagiocephaly at the Craniofacial Center at Seattle Children's Hospital. Risk factor information was abstracted from birth certificate and hospital discharge data and unconditional logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI). Cases (n = 2764) were more likely than controls (n = 13 817) to have been injured at birth (OR 1.4; 95% CI 1.2, 1.7) or diagnosed with a congenital anomaly (OR 2.0; 95% CI 1.8, 2.3). Cases were more likely to have been male, a twin, or small-for-gestational-age. This first large-scale, case-control study of risk factors for plagiocephaly in a U.S. population provides new evidence that birth injuries and congenital anomalies are associated with plagiocephaly risk. PMID:19523080

  14. Assessing risk factors of sporadic Campylobacter infection: a case-control study in Arizona.

    PubMed

    Pogreba-Brown, K; Baker, A; Ernst, K; Stewart, J; Harris, R B; Weiss, J

    2016-03-01

    Case-control studies of sporadic Campylobacter infections have predominately been conducted in non-Hispanic populations. In Arizona, rates of campylobacteriosis have been historically higher than the national average, with particularly high rates in Hispanics. In 2010, health departments and a state university collaborated to conduct a statewide case-control study to determine whether risk factors differ in an ethnically diverse region of the United States. Statistically significant risk factors in the final multivariate model were: eating cantaloupe [odds ratio (OR) 7·64], handling raw poultry (OR 4·88) and eating queso fresco (OR 7·11). In addition, compared to non-Hispanic/non-travellers, the highest risk group were Hispanic/non-travellers (OR 7·27), and Hispanic/travellers (OR 5·87, not significant). Results of this study suggest Hispanics have higher odds of disease, probably due to differential exposures. In addition to common risk factors, consumption of cantaloupe was identified as a significant risk factor. These results will inform public health officials of the varying risk factors for Campylobacter in this region. PMID:26828241

  15. Does benzene cause multiple myeloma? An analysis of the published case-control literature.

    PubMed

    Bezabeh, S; Engel, A; Morris, C B; Lamm, S H

    1996-12-01

    Two case series and two epidemiological studies in the 1970s and 1980s suggested that benzene exposure might be a risk factor for multiple myeloma. An analysis has now been conducted of the published population-based and hospital-based case-control studies published through mid-1995 that permit examination of the relationship between multiple myeloma and benzene exposure or surrogates for benzene exposure. No increased association was found between multiple myeloma and benzene exposure or exposure to chemical groups that included benzene. The odds ratios from these analyses approximated 1.0. Exposures to petroleum products and employment in petroleum-related occupations did not appear to be risk factors for multiple myeloma. Cigarette smoking, as a surrogate of benzene exposure, was not found to be associated with myeloma, while some studies of products of combustion described as "engine exhaust" did show a significant association with multiple myeloma. In toto, the population-based and hospital-based case-control literature indicated that benzene exposure was not a likely causal factor for multiple myeloma.

  16. Bridging ImmunoGenomic Data Analysis Workflow Gaps (BIGDAWG): An integrated case-control analysis pipeline.

    PubMed

    Pappas, Derek J; Marin, Wesley; Hollenbach, Jill A; Mack, Steven J

    2016-03-01

    Bridging ImmunoGenomic Data-Analysis Workflow Gaps (BIGDAWG) is an integrated data-analysis pipeline designed for the standardized analysis of highly-polymorphic genetic data, specifically for the HLA and KIR genetic systems. Most modern genetic analysis programs are designed for the analysis of single nucleotide polymorphisms, but the highly polymorphic nature of HLA and KIR data require specialized methods of data analysis. BIGDAWG performs case-control data analyses of highly polymorphic genotype data characteristic of the HLA and KIR loci. BIGDAWG performs tests for Hardy-Weinberg equilibrium, calculates allele frequencies and bins low-frequency alleles for k×2 and 2×2 chi-squared tests, and calculates odds ratios, confidence intervals and p-values for each allele. When multi-locus genotype data are available, BIGDAWG estimates user-specified haplotypes and performs the same binning and statistical calculations for each haplotype. For the HLA loci, BIGDAWG performs the same analyses at the individual amino-acid level. Finally, BIGDAWG generates figures and tables for each of these comparisons. BIGDAWG obviates the error-prone reformatting needed to traffic data between multiple programs, and streamlines and standardizes the data-analysis process for case-control studies of highly polymorphic data. BIGDAWG has been implemented as the bigdawg R package and as a free web application at bigdawg.immunogenomics.org.

  17. An open multicenter comparative randomized clinical study on chitosan.

    PubMed

    Mo, Xiaohui; Cen, John; Gibson, Elaine; Wang, Robin; Percival, Steven L

    2015-01-01

    Chitosan, a natural polysaccharide derivate from chitin, offers a promising alternative biomaterial for use in wound dressings. In this work, the safety and efficacy of a next-generation KA01 chitosan wound dressing in facilitating the healing of nonhealing chronic wounds was studied. This open multicenter comparative prospective randomized clinical study was conducted at three medical centers in China. A total of 90 patients (45 in test group and 45 in control group) with unhealed chronic wounds including pressure ulcers, vascular ulcers, diabetic foot ulcers, and wounds with minor infections, or at risk of infection, were treated with the next generation chitosan wound dressing as the test article or traditional vaseline gauze as a control. Baseline assessments were undertaken with the primary end point being wound area reduction. The secondary end points included pain reduction (using the NRS11 pain scale) at dressing change, wound exudate levels, wound depth and duration of the treatment. After 4 weeks treatment, the wound area reduction was significantly greater in the test group (65.97 ± 4.48%) than the control group (39.95 ± 4.48%). The average pain level in the test group was 1.12 ± 0.23 and 2.30 ± 0.23 in the control group. The wound depth was also lower in the test group 0.30 ± 0.48 cm than the control group 0.54 ± 0.86 cm. The level of exudate fell and the dressing could be removed integrally in both the test and control groups. The mean duration of the test group was 27.31 ± 5.37 days and control group 27.09 ± 6.44 days. No adverse events were reported in either group. In conclusion this open multicenter comparative prospective randomized clinical study has provided compelling evidence that the next generation chitosan wound dressing can enhance wound progression towards healing by facilitating wound reepithelialization and reducing the patients pain level. Furthermore the dressing was shown to be clinically safe and effective in the management

  18. An open multicenter comparative randomized clinical study on chitosan.

    PubMed

    Mo, Xiaohui; Cen, John; Gibson, Elaine; Wang, Robin; Percival, Steven L

    2015-01-01

    Chitosan, a natural polysaccharide derivate from chitin, offers a promising alternative biomaterial for use in wound dressings. In this work, the safety and efficacy of a next-generation KA01 chitosan wound dressing in facilitating the healing of nonhealing chronic wounds was studied. This open multicenter comparative prospective randomized clinical study was conducted at three medical centers in China. A total of 90 patients (45 in test group and 45 in control group) with unhealed chronic wounds including pressure ulcers, vascular ulcers, diabetic foot ulcers, and wounds with minor infections, or at risk of infection, were treated with the next generation chitosan wound dressing as the test article or traditional vaseline gauze as a control. Baseline assessments were undertaken with the primary end point being wound area reduction. The secondary end points included pain reduction (using the NRS11 pain scale) at dressing change, wound exudate levels, wound depth and duration of the treatment. After 4 weeks treatment, the wound area reduction was significantly greater in the test group (65.97 ± 4.48%) than the control group (39.95 ± 4.48%). The average pain level in the test group was 1.12 ± 0.23 and 2.30 ± 0.23 in the control group. The wound depth was also lower in the test group 0.30 ± 0.48 cm than the control group 0.54 ± 0.86 cm. The level of exudate fell and the dressing could be removed integrally in both the test and control groups. The mean duration of the test group was 27.31 ± 5.37 days and control group 27.09 ± 6.44 days. No adverse events were reported in either group. In conclusion this open multicenter comparative prospective randomized clinical study has provided compelling evidence that the next generation chitosan wound dressing can enhance wound progression towards healing by facilitating wound reepithelialization and reducing the patients pain level. Furthermore the dressing was shown to be clinically safe and effective in the management

  19. Economic Impact of Dengue: Multicenter Study across Four Brazilian Regions

    PubMed Central

    Martelli, Celina Maria Turchi; Siqueira, Joao Bosco; Parente, Mirian Perpetua Palha Dias; Zara, Ana Laura de Sene Amancio; Oliveira, Consuelo Silva; Braga, Cynthia; Pimenta, Fabiano Geraldo; Cortes, Fanny; Lopez, Juan Guillermo; Bahia, Luciana Ribeiro; Mendes, Marcia Costa Ooteman; da Rosa, Michelle Quarti Machado; de Siqueira Filha, Noemia Teixeira; Constenla, Dagna; de Souza, Wayner Vieira

    2015-01-01

    Background Dengue is an increasing public health concern in Brazil. There is a need for an updated evaluation of the economic impact of dengue within the country. We undertook this multicenter study to evaluate the economic burden of dengue in Brazil. Methods We estimated the economic burden of dengue in Brazil for the years 2009 to 2013 and for the epidemic season of August 2012- September 2013. We conducted a multicenter cohort study across four endemic regions: Midwest, Goiania; Southeast, Belo Horizonte and Rio de Janeiro; Northeast: Teresina and Recife; and the North, Belem. Ambulatory or hospitalized cases with suspected or laboratory-confirmed dengue treated in both the private and public sectors were recruited. Interviews were scheduled for the convalescent period to ascertain characteristics of the dengue episode, date of first symptoms/signs and recovery, use of medical services, work/school absence, household spending (out-of-pocket expense) and income lost using a questionnaire developed for a previous cost study. We also extracted data from the patients’ medical records for hospitalized cases. Overall costs per case and cumulative costs were calculated from the public payer and societal perspectives. National cost estimations took into account cases reported in the official notification system (SINAN) with adjustment for underreporting of cases. We applied a probabilistic sensitivity analysis using Monte Carlo simulations with 90% certainty levels (CL). Results We screened 2,223 cases, of which 2,035 (91.5%) symptomatic dengue cases were included in our study. The estimated cost for dengue for the epidemic season (2012–2013) in the societal perspective was US$ 468 million (90% CL: 349–590) or US$ 1,212 million (90% CL: 904–1,526) after adjusting for under-reporting. Considering the time series of dengue (2009–2013) the estimated cost of dengue varied from US$ 371 million (2009) to US$ 1,228 million (2013). Conclusions The economic burden

  20. Case-Control Studies of Sporadic Enteric Infections: A Review and Discussion of Studies Conducted Internationally from 1990 to 2009

    PubMed Central

    Fullerton, Kathleen E.; Scallan, Elaine; Kirk, Martyn D.; Mahon, Barbara E.; Angulo, Frederick J.; de Valk, Henriette; van Pelt, Wilfrid; Gauci, Charmaine; Hauri, Anja M.; Majowicz, Shannon; O’Brien, Sarah J.

    2015-01-01

    Epidemiologists have used case-control studies to investigate enteric disease outbreaks for many decades. Increasingly, case-control studies are also used to investigate risk factors for sporadic (not outbreak-associated) disease. While the same basic approach is used, there are important differences between outbreak and sporadic disease settings that need to be considered in the design and implementation of the case-control study for sporadic disease. Through the International Collaboration on Enteric Disease “Burden of Illness” Studies (the International Collaboration), we reviewed 79 case-control studies of sporadic enteric infections caused by nine pathogens that were conducted in 22 countries and published from 1990 through to 2009. We highlight important methodological and study design issues (including case definition, control selection, and exposure assessment) and discuss how approaches to the study of sporadic enteric disease have changed over the last 20 years (e.g., making use of more sensitive case definitions, databases of controls, and computer-assisted interviewing). As our understanding of sporadic enteric infections grows, methods and topics for case-control studies are expected to continue to evolve; for example, advances in understanding of the role of immunity can be used to improve control selection, the apparent protective effects of certain foods can be further explored, and case-control studies can be used to provide population-based measures of the burden of disease. PMID:22443481

  1. Toilet training age and influencing factors: a multicenter study.

    PubMed

    Tarhan, Hüseyin; Çakmak, Özgür; Akarken, İlker; Ekin, Rahmi Gökhan; Ün, Sıtkı; Uzelli, Derya; Helvacı, Mehmet; Aksu, Nejat; Yavaşcan, Önder; Mutlubaş Özsan, Fatma; Cun, Selma; Koç, Feyza; Özkarakaş, Özlem; İlbey, Yusuf Özlem; Zorlu, Ferruh

    2015-01-01

    To determine toilet training age and the factors influencing this in our country, 1500 children who had completed toilet training were evaluated in a multicenter study. The mean age of toilet training was 22.32 ± 6.57 months. The duration it took to complete toilet training was 6.60 ± 2.20 months on the average. In univariant analysis, toilet training age increased as the parental education level, specifically that of the mother, increased. The training age of children whose mothers had over 12 years of education differed significantly from that of children of mothers with less education. There was no significant difference in toilet training age with regard to the education level of the father, or the employment status of the mother. We also found significant differences with respect to family income level, toilet type and training method. In multivariant analysis, family income >5000 TL and use of a potty chair were determined to be factors affecting toilet training age. In conclusion, toilet training age in Turkey, a developing country, was found to be lower than that in developed countries.

  2. Quantitative MR in multi-center clinical trials.

    PubMed

    Ashton, Edward

    2010-02-01

    MRI has a wide variety of applications in the clinical trials process. MR has shown particular utility in the early phases of clinical development, when trial sponsors are interested in demonstrating proof of concept and must make decisions about allocation of resources to a particular compound based on the results from a small number of experimental subjects. This utility is largely due to the many different imaging endpoints that can be measured using MR, ranging from structural (tumor burden, hippocampal volume) to functional (blood flow, vascular permeability) to molecular (hepatic fat fraction, glycosaminoglycan content). The unique flexibility of these systems has proven to be both a blessing and a curse to those attempting to deploy MR in multi-center clinical trials, however, as differences among scanner manufacturers and models in pulse sequence implementation, hardware capabilities, and even terminology make it increasingly difficult to ensure that results obtained at one center are comparable to those at another. These problems are compounded by the differences between the procedures used in clinical trials and those used in routine clinical practice, which make trial-specific training for site technologists and radiologists a necessity in many cases. This article will briefly review the benefits of including quantitative MR imaging in clinical trials, then explore in detail the challenges presented by the need to develop and deploy a detailed MR protocol that is both effective and implementable across many different MR systems and software versions.

  3. Guidelines for quality assurance in multicenter trials: a position paper.

    PubMed

    Knatterud, G L; Rockhold, F W; George, S L; Barton, F B; Davis, C E; Fairweather, W R; Honohan, T; Mowery, R; O'Neill, R

    1998-10-01

    In the wake of reports of falsified data in one of the trials of the National Surgical Adjuvant Project for Breast and Bowel Cancer supported by the National Cancer Institute, clinical trials came under close scrutiny by the public, the press, and Congress. Questions were asked about the quality and integrity of the collected data and the analyses and conclusions of trials. In 1995, the leaders of the Society for Clinical Trials (the Chair of the Policy Committee, Dr. David DeMets, and the President of the Society, Dr. Sylvan Green) asked two members of the Society (Dr. Genell Knatterud and Dr. Frank Rockhold) to act as co-chairs of a newly formed subcommittee to discuss the issues of data integrity and auditing. In consultation with Drs. DeMets and Green, the co-chairs selected other members (Ms. Franca Barton, Dr. C.E. Davis, Dr. Bill Fairweather, Dr. Stephen George, Mr. Tom Honohan, Dr. Richard Mowery, and Dr. Robert O'Neill) to serve on the subcommittee. The subcommittee considered "how clean clinical trial data should be, to what extent auditing procedures are required, and who should conduct audits and how often." During the initial discussions, the subcommittee concluded that data auditing was insufficient to achieve data integrity. Accordingly, the subcommittee prepared this set of guidelines for standards of quality assurance for multicenter clinical trials. We include recommendations for appropriate action if problems are detected.

  4. Local response dispersion method. II. Generalized multicenter interactions

    NASA Astrophysics Data System (ADS)

    Sato, Takeshi; Nakai, Hiromi

    2010-11-01

    Recently introduced local response dispersion method [T. Sato and H. Nakai, J. Chem. Phys. 131, 224104 (2009)], which is a first-principles alternative to empirical dispersion corrections in density functional theory, is implemented with generalized multicenter interactions involving both atomic and atomic pair polarizabilities. The generalization improves the asymptote of intermolecular interactions, reducing the mean absolute percentage error from about 30% to 6% in the molecular C6 coefficients of more than 1000 dimers, compared to experimental values. The method is also applied to calculations of potential energy curves of molecules in the S22 database [P. Jurečka et al., Phys. Chem. Chem. Phys. 8, 1985 (2006)]. The calculated potential energy curves are in a good agreement with reliable benchmarks recently published by Molnar et al. [J. Chem. Phys. 131, 065102 (2009)]. These improvements are achieved at the price of increasing complexity in the implementation, but without losing the computational efficiency of the previous two-center (atom-atom) formulation. A set of different truncations of two-center and three- or four-center interactions is shown to be optimal in the cost-performance balance.

  5. Multicenter Australian trial of islet transplantation: improving accessibility and outcomes.

    PubMed

    O'Connell, P J; Holmes-Walker, D J; Goodman, D; Hawthorne, W J; Loudovaris, T; Gunton, J E; Thomas, H E; Grey, S T; Drogemuller, C J; Ward, G M; Torpy, D J; Coates, P T; Kay, T W

    2013-07-01

    Whilst initial rates of insulin independence following islet transplantation are encouraging, long-term function using the Edmonton Protocol remains a concern. The aim of this single-arm, multicenter study was to evaluate an immunosuppressive protocol of initial antithymocyte globulin (ATG), tacrolimus and mycophenolate mofetil (MMF) followed by switching to sirolimus and MMF. Islets were cultured for 24 h prior to transplantation. The primary end-point was an HbA1c of <7% and cessation of severe hypoglycemia. Seventeen recipients were followed for ≥ 12 months. Nine islet preparations were transported interstate for transplantation. Similar outcomes were achieved at all three centers. Fourteen of the 17 (82%) recipients achieved the primary end-point. Nine (53%) recipients achieved insulin independence for a median of 26 months (range 7-39 months) and 6 (35%) remain insulin independent. All recipients were C-peptide positive for at least 3 months. All subjects with unstimulated C-peptide >0.2 nmol/L had cessation of severe hypoglycemia. Nine of the 17 recipients tolerated switching from tacrolimus to sirolimus with similar graft outcomes. There was a small but significant reduction in renal function in the first 12 months. The combination of islet culture, ATG, tacrolimus and MMF is a viable alternative for islet transplantation. PMID:23668890

  6. Ethics review of pediatric multi-center drug trials.

    PubMed

    Needham, Allison C; Kapadia, Mufiza Z; Offringa, Martin

    2015-02-01

    The assessment of safety and efficacy of therapeutics for children and adolescents requires the use of multi-centered designs. However, the need to obtain ethical approval from multiple independent research ethics boards (REBs) presents as a challenge to investigators and sponsors who must consider local requirements while ensuring that the protection of human subjects is consistent across sites. In pediatrics, this requirement is complicated by pediatric-specific ethical concerns such as the acquisition of assent and consent and the need for pediatric expertise to assess the scholarly merit of the proposed research. Efforts to tackle these challenges have focused on the process of ethics review, which will improve efficiency. In addition to improving process, we suggest further research to fill gaps in the evidence base for recommendations and decisions made by REBs, specifically their effectiveness to protect human subjects. Evidence gathered will contribute to the successful development, adoption and implementation of harmonized guidance to apply ethics principles in order to protect children through research rather than from research.

  7. Emergency Care for Homeless Patients: A French Multicenter Cohort Study

    PubMed Central

    Feral-Pierssens, Anne-Laure; Aubry, Adeline; Truchot, Jennifer; Raynal, Pierre-Alexis; Boiffier, Mathieu; Hutin, Alice; Leleu, Agathe; Debruyne, Geraud; Joly, Luc-Marie; Juvin, Philippe; Riou, Bruno

    2016-01-01

    Objectives. To determine whether homeless patients experience suboptimal care in the emergency department (ED) by the provision of fewer health care resources. Methods. We conducted a prospective multicenter cohort study in 30 EDs in France. During 72 hours in March 2015, all homeless patients that visited the participating EDs were included in the study. The primary health care service measure was the order by the physician of a diagnostic investigation or provision of a treatment in the ED. Secondary measures of health care services included ED waiting time, number and type of investigations per patient, treatment in the ED, and discharge disposition. Results. A total of 254 homeless patients and 254 nonhomeless patients were included. After excluding homeless patients that attended the ED for the sole purpose of housing, we analyzed 214 homeless and 214 nonhomeless. We found no significant difference between the 2 groups in terms of health care resource consumption, and for our secondary endpoints. Conclusions. We did not find significant differences in the level of medical care delivered in French EDs to homeless patients compared with matched nonhomeless patients. PMID:26985613

  8. Associations of serum organohalogen levels and prostate cancer risk: Results from a case-control study in Singapore.

    PubMed

    Pi, Na; Chia, Sin Eng; Ong, Choon Nam; Kelly, Barry C

    2016-02-01

    There is increasing evidence that elevated exposure to organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) may lead to an increased risk of prostate cancer. As part of a hospital-based case-control study of the Singaporean male population, we investigated associations between organohalogen exposure and risk of prostate cancer. Trace residue concentrations of 74 organohalogen contaminants, including several PCBs, OCPs and halogenated flame retardants (HFRs), were determined in serum samples (n = 120) using gas chromatography tandem mass spectrometry (GC-MS/MS). A variety of OCPs, PCBs and HFRs were detected in samples of both patients and controls. Mean concentrations of p,p' DDT, p,p' DDE, PCB 118, PCB 138, PCB 153 and PCB 187 were significantly higher (p < 0.05) in serum of patients. p,p' DDE measured in serum of patients was relatively high (mean:13,700 ng/g lipid, 95% CI:7000-26,800). Odds ratios (ORs) of OCPs and PCBs in many cases exceeded 1. ORs for p,p' DDE and PCB-153 at the highest tertile (>67th) were 5.67 (95% CI, 2.37-13.54) and 2.14 (95% CI, 0.99 to 4.66), respectively. The results suggest that exposure to DDTs and PCBs may be associated with prostate cancer risk in Singaporean males. No such association was observed for the organohalogen flame retardants studied, including polybrominated diphenyl ethers (PBDEs). The study provides novel information regarding the occurrence, levels and potential associations with prostate cancer risk for several organohalogen contaminants in the Singapore population. However, further investigation and analyses should be conducted to confirm these findings.

  9. A multicenter evaluation of assays for detection of SV40 DNA and results in masked mesothelioma specimens.

    PubMed

    Strickler, H D

    2001-05-01

    This nine-laboratory multicenter investigation was designed to assess the sensitivity, specificity, and reproducibility of previously described assays for detection of SV40 DNA with three goals, i.e., (a) to compare methods for testing human tissues, (b) to examine the ability of these methods to detect SV40 in human mesotheliomas, and (c) to uncover assay differences that could explain conflicting findings in some past investigations. Each laboratory received, in a masked fashion, paired replicate DNA samples extracted from 25 fresh frozen mesotheliomas (50 samples) and one from each of 25 normal human lungs. Interspersed were masked positive (titrations of the SV40 genome) and negative control samples. Preliminary studies confirmed the adequacy of the samples for testing high molecular weight double-stranded linear DNA targets. All 15 PCR-based assays detected 5,000 copies or less of the SV40 genome spiked into 2 microg of WI-38 DNA. A high level of specificity and reproducibility was found among the PCR assays performed in most laboratories. However, none of the selected normal human lung tissue or the 25 mesothelioma tumor specimens obtained from archival samples at a single center was reproducibly positive for the presence of SV40 DNA. Further studies are needed to reconcile these results with previous reports of detection of SV40 DNA in tumor specimens.

  10. Acceptance of living liver donation among medical students: A multicenter stratified study from Spain

    PubMed Central

    Ríos, Antonio; López-Navas, Ana Isabel; López-López, Ana Isabel; Gómez, Francisco Javier; Iriarte, Jorge; Herruzo, Rafael; Blanco, Gerardo; Llorca, Francisco Javier; Asunsolo, Angel; Sánchez-Gallegos, Pilar; Gutiérrez, Pedro Ramón; Fernández, Ana; de Jesús, María Teresa; Martínez-Alarcón, Laura; Lana, Alberto; Fuentes, Lorena; Hernández, Juan Ramón; Virseda, Julio; Yelamos, José; Bondía, José Antonio; Hernández, Antonio Miguel; Ayala, Marco Antonio; Ramírez, Pablo; Parrilla, Pascual

    2016-01-01

    AIM: To analyze the attitude of Spanish medical students toward living liver donation (LLD) and to establish which factors have an influence on this attitude. METHODS: Study type: A sociological, interdisciplinary, multicenter and observational study. Study population: Medical students enrolled in Spain (n = 34000) in the university academic year 2010-2011. Sample size: A sample of 9598 students stratified by geographical area and academic year. Instrument used to measure attitude: A validated questionnaire (PCID-DVH RIOS) was self-administered and completed anonymously. Data collection procedure: Randomly selected medical schools. The questionnaire was applied to each academic year at compulsory sessions. Statistical analysis: Student´s t test, χ2 test and logistic regression analysis. RESULTS: The completion rate was 95.7% (n = 9275). 89% (n = 8258) were in favor of related LLD, and 32% (n = 2937) supported unrelated LLD. The following variables were associated with having a more favorable attitude: (1) age (P = 0.008); (2) sex (P < 0.001); (3) academic year (P < 0.001); (4) geographical area (P = 0.013); (5) believing in the possibility of needing a transplant oneself in the future (P < 0.001); (6) attitude toward deceased donation (P < 0.001); (7) attitude toward living kidney donation (P < 0.001); (8) acceptance of a donated liver segment from a family member if one were needed (P < 0.001); (9) having discussed the subject with one's family (P < 0.001) and friends (P < 0.001); (10) a partner's opinion about the subject (P < 0.001); (11) carrying out activities of an altruistic nature; and (12) fear of the possible mutilation of the body after donation (P < 0.001). CONCLUSION: Spanish medical students have a favorable attitude toward LLD. PMID:27433093

  11. Acrylamide and glycidamide hemoglobin adducts and epithelial ovarian cancer: a nested case-control study in non-smoking postmenopausal women from the EPIC cohort

    PubMed Central

    Obón-Santacana, Mireia; Lujan-Barroso, Leila; Travis, Ruth C.; Freisling, Heinz; Ferrari, Pietro; Severi, Gianluca; Baglietto, Laura; Boutron-Ruault, Marie-Christine; Fortner, Renée T.; Ose, Jennifer; Boeing, Heiner; Menéndez, Virginia; Sánchez-Cantalejo, Emilio; Chamosa, Saioa; Huerta Castaño, José María; Ardanaz, Eva; Khaw, Kay-Tee; Wareham, Nick; Merritt, Melissa A.; Gunter, Marc J.; Trichopoulou, Antonia; Papatesta, Eleni-Maria; Klinaki, Eleni; Saieva, Calogero; Tagliabue, Giovanna; Tumino, Rosario; Sacerdote, Carlotta; Mattiello, Amalia; Bueno-de-Mesquita, H.B.; Peeters, Petra H.; Onland-Moret, N. Charlotte; Idahl, Annika; Lundin, Eva; Weiderpass, Elisabete; Vesper, Hubert W.; Riboli, Elio; Duell, Eric J

    2015-01-01

    Background Acrylamide was classified as ‘probably carcinogenic to humans (group 2A)’ by the International Agency for Research on Cancer. Epithelial ovarian cancer (EOC) is the fourth cause of cancer mortality in women. Five epidemiological studies have evaluated the association between EOC risk and dietary acrylamide intake assessed using food frequency questionnaires, and one nested case-control study evaluated hemoglobin adducts of acrylamide (HbAA) and its metabolite glycidamide (HbGA) and EOC risk; the results of these studies were inconsistent. Methods A nested case-control study in non-smoking postmenopausal women (334 cases, 417 controls) was conducted within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. Unconditional logistic regression models were used to estimate odds ratios (OR) and 95% confidence intervals (CI) for the association between HbAA, HbGA, HbAA+HbGA, and HbGA/HbAA and EOC and invasive serous EOC risk. Results No overall associations were observed between biomarkers of acrylamide exposure analyzed in quintiles and EOC risk; however, positive associations were observed between some middle quintiles of HbGA and HbAA+HbGA. Elevated but non-statistically significant ORs for serous EOC were observed for HbGA and HbAA+HbGA (ORQ5vsQ1:1.91, 95%CI:0.96-3.81 and ORQ5vsQ1:1.90, 95%CI:0.94-3.83, respectively); however, no linear dose-response trends were observed. Conclusion This EPIC nested case-control study failed to observe a clear association between biomarkers of acrylamide exposure and the risk of EOC or invasive serous EOC. Impact It is unlikely that dietary acrylamide exposure increases ovarian cancer risk; however, additional studies with larger sample size should be performed to exclude any possible association with EOC risk. PMID:26376083

  12. Rare UNC13B variations and risk of schizophrenia: Whole-exome sequencing in a multiplex family and follow-up resequencing and a case-control study.

    PubMed

    Egawa, Jun; Hoya, Satoshi; Watanabe, Yuichiro; Nunokawa, Ayako; Shibuya, Masako; Ikeda, Masashi; Inoue, Emiko; Okuda, Shujiro; Kondo, Kenji; Saito, Takeo; Kaneko, Naoshi; Muratake, Tatsuyuki; Igeta, Hirofumi; Iwata, Nakao; Someya, Toshiyuki

    2016-09-01

    Rare genomic variations inherited in multiplex schizophrenia families are suggested to play a role in the genetic etiology of the disease. To identify rare variations with large effects on the risk of developing schizophrenia, we performed whole-exome sequencing (WES) in two affected and one unaffected individual of a multiplex family with 10 affected individuals. We also performed follow-up resequencing of the unc-13 homolog B (Caenorhabditis elegans) (UNC13B) gene, a potential risk gene identified by WES, in the multiplex family and undertook a case-control study to investigate association between UNC13B and schizophrenia. UNC13B coding regions (39 exons) from 15 individuals of the multiplex family and 111 affected offspring for whom parental DNA samples were available were resequenced. Rare missense UNC13B variations identified by resequencing were further tested for association with schizophrenia in two independent case-control populations comprising a total of 1,753 patients and 1,602 controls. A rare missense variation (V1525M) in UNC13B was identified by WES in the multiplex family; this variation was present in five of six affected individuals, but not in eight unaffected individuals or one individual of unknown disease status. Resequencing UNC13B coding regions identified five rare missense variations (T103M, M813T, P1349T, I1362T, and V1525M). In the case-control study, there was no significant association between rare missense UNC13B variations and schizophrenia, although single-variant meta-analysis indicated that M813T was nominally associated with schizophrenia. These results do not support a contribution of rare missense UNC13B variations to the genetic etiology of schizophrenia in the Japanese population. © 2016 Wiley Periodicals, Inc. PMID:26990377

  13. The association between component malalignment and post-operative pain following navigation-assisted total knee arthroplasty: results of a cohort/nested case-control study.

    PubMed

    Czurda, Thomas; Fennema, Peter; Baumgartner, Martin; Ritschl, Peter

    2010-07-01

    Previous studies have noted an adverse relationship between implant malalignment during total knee arthroplasty (TKA) and post-operative pain. Although some evidence exists indicating that computer-assisted surgical navigation for TKA can improve the accuracy of component alignment, its impact on clinical outcomes is currently unknown. The dual goals of the present cohort/nested case-control study were to (1) compare self-reported responses to the Western Ontario-McMaster Osteoarthritis Index (WOMAC) questionnaire between computer-assisted TKA (123 patients) using the imageless PiGalileo navigation system and conventional TKA (207 patients) [cohort analysis], and (2) to investigate a potential association between malalignment and post-operative pain in 19 painful knees and 19 asymptomatic knees obtained from the cohort analysis using matched sampling [nested case-control study]. In the cohort analysis, a relevant but non-significant (P = 0.06) difference in the occurrence of chronic pain was observed between the navigated (12%) and conventional arms (20%). Median post-operative WOMAC pain score was 100 (range, 50-100) in the conventional group and 100 (range, 65-100) in the navigated group. However, the Mann-Whitney test revealed a significant difference in favor of the navigated group (P = 0.01). In the nested case-control analysis, radiological outcomes and computer tomography (CT) measurements of femoral rotation were compared between the groups. The CT rotation measurements yielded evidence of a relationship between post-operative pain and incorrect rotational alignment of the femoral component of more than 3 degrees (OR: 7; 95% CI: 1.2-42; P = .033). In conclusion, there was no clinical benefit to computer-assisted navigation; however, a statistically significant relationship was observed between incorrect rotational alignment of the femoral component and symptoms of post-operative pain following TKA.

  14. Application of a nanotechnology antimicrobial spray to prevent lower urinary tract infection: a multicenter urology trial

    PubMed Central

    2012-01-01

    Background Catheter-associated urinary tract infection (CAUTI) is a common nosocomial device-associated infection. It is now recognized that the high infection rates were caused by the formation of biofilm on the surface of the catheters that decreases the susceptibility to antibiotics and results in anti-microbial resistance. In this study, we performed an in vitro test to explore the mechanism of biofilm formation and subsequently conducted a multi-center clinical trial to investigate the efficacy of CAUTI prevention with the application of JUC, a nanotechnology antimicrobial spray. Methods Siliconized latex urinary catheters were cut into fragments and sterilized by autoclaving. The sterilized sample fragments were randomly divided into the therapy and control group, whereby they were sprayed with JUC and distilled water respectively and dried before use. The experimental standard strains of Escherichia coli (E. coli) were isolated from the urine samples of patients. At 16 hours and 7 days of incubation, the samples were extracted for confocal laser scanning microscopy. A total of 1,150 patients were accrued in the clinical study. Patients were randomized according to the order of surgical treatment. The odd array of patients was assigned as the therapy group (JUC), and the even array of patients was assigned as the control group (normal saline). Results After 16 hours of culture, bacterial biofilm formed on the surface of sample fragments from the control group. In the therapy group, no bacterial biofilm formation was observed on the sample fragments. No significant increase in bacterial colony count was observed in the therapy group after 7 days of incubation. On the 7th day of catheterization, urine samples were collected for bacterial culture before extubation. Significant difference was observed in the incidence of bacteriuria between the therapy group and control group (4.52% vs. 13.04%, p < 0.001). Conclusions In this study, the effectiveness of JUC in

  15. Carcinogenicity of chrysotile asbestos: a case control study of textile workers

    SciTech Connect

    Dement, J.M. )

    1991-01-01

    Chrysotile is the predominant type of asbestos used in the United States and thus represents the most important source of exposure to asbestos already in place. While the steepest exposure-response observed for lung cancer has been in workers exposed to chrysotile in textile operations, some argue that chrysotile is less carcinogenic than amphibole asbestos types. Mineral oil exposures have been hypothesized to be responsible for the highly elevated lung cancer risk seen in textile workers. A lung cancer case-control analysis among a cohort of South Carolina chrysotile asbestos textile workers was conducted. Only a modest reduction in the slope of the lung cancer exposure-response relationship was observed after controlling for mineral oil exposures. These data do not support mineral oil exposure as a plausible explanation for the elevated lung cancer risk seen in chrysotile asbestos textile workers. The possible role of longer, thinner, more carcinogenic fibers in textiles is one plausible hypothesis needing further investigation.

  16. Case-control study of nasal cancer in workers employed in wood-related industries.

    PubMed

    Viren, J R; Imbus, H R

    1989-01-01

    A case-control study of nasal cancer deaths in the states of Washington, Oregon, Mississippi, and North Carolina was undertaken to determine whether there was an excess of nasal cancer deaths occurring among workers in wood-related industries. This involved analysis of 536 cases of nasal cancer deaths occurring from 1962 to 1977, compared with 1,072 deaths matched for control. The study showed no overall excess of deaths from nasal cancer in wood-related industries, including furniture manufacturing. There was a statistically significant excess of deaths from nasal cancer occurring in lumber and wood products (risk ratio = 1.95, P less than .05); however, this was largely due to excess in these industries occurring in the states, of North Carolina and Mississippi. Summarizing the available evidence of this study, there seems to be no association between nasal cancer and industry/occupation normally identified with wood dust.

  17. Case-control studies of sporadic cryptosporidiosis in Melbourne and Adelaide, Australia.

    PubMed

    Robertson, B; Sinclair, M I; Forbes, A B; Veitch, M; Kirk, M; Cunliffe, D; Willis, J; Fairley, C K

    2002-06-01

    Few studies have assessed risk factors for sporadic cryptosporidiosis in industrialized countries, even though it may be numerically more common than outbreaks of disease. We carried out case-control studies assessing risk factors for sporadic disease in Melbourne and Adelaide, which have water supplies from different ends of the raw water spectrum. In addition to examining drinking water, we assessed several other exposures. 201 cases and 795 controls were recruited for Melbourne and 134 cases and 536 controls were recruited for Adelaide. Risk factors were similar for the two cities, with swimming in public pools and contact with a person with diarrhoea being most important. The consumption of plain tap water was not found to be associated with disease. This study emphasizes the need for regular public health messages to the public and swimming pool managers in an attempt to prevent sporadic cryptosporidiosis, as well as outbreaks of disease.

  18. A case control study to improve accuracy of an electronic fall prevention toolkit.

    PubMed

    Dykes, Patricia C; I-Ching, Evita Hou; Soukup, Jane R; Chang, Frank; Lipsitz, Stuart

    2012-01-01

    Patient falls are a serious and commonly report adverse event in hospitals. In 2009, our team conducted the first randomized control trial of a health information technology-based intervention that significantly reduced falls in acute care hospitals. However, some patients on intervention units with access to the electronic toolkit fell. The purpose of this case control study was to use data mining and modeling techniques to identify the factors associated with falls in hospitalized patients when the toolkit was in place. Our ultimate aim was to apply our findings to improve the toolkit logic and to generate practice recommendations. The results of our evaluation suggest that the fall prevention toolkit logic is accurate but strategies are needed to improve adherence with the fall prevention intervention recommendations generated by the electronic toolkit.

  19. Relationship between air pollution and pre-eclampsia in pregnant women: a case-control study.

    PubMed

    Nahidi, F; Gholami, R; Rashidi, Y; Majd, H Alavi

    2014-01-09

    Pre-eclampsia is the main cause of maternal and fetal death and disability worldwide. Its incidence in the Islamic Republic of Iran is 5%-12%. Air pollution has been reported to be one of the causative factors, and this case-control study determined its effect on pre-eclampsia in 195 pregnant women (65 with pre-eclampsia and 130 without) admitted to hospitals in Tehran. Women were divided into high and low exposure groups according to the mean density of exposure to pollutants during pregnancy. There was no statistically significant relationship between exposure to air pollutants including CO, particulate matter, SO2, NO2 and O3 and pre-eclampsia. The combined effect was also not significant. Air pollution is one of the problems of modern society and its avoidance is almost impossible for pregnant women. This study should reduce concern about pregnant women living in polluted cities.

  20. Sleep problems and suicide attempts among adolescents: a case-control study.

    PubMed

    Koyawala, Neel; Stevens, Jack; McBee-Strayer, Sandra M; Cannon, Elizabeth A; Bridge, Jeffrey A

    2015-01-01

    This study used a case-control design to compare sleep disturbances in 40 adolescents who attempted suicide with 40 never-suicidal adolescents. Using hierarchical logistic regression analyses, we found that self-reported nighttime awakenings were significantly associated with attempted suicide, after controlling for antidepressant use, antipsychotic use, affective problems, and being bullied. In a separate regression analysis, the parent-reported total sleep problems score also predicted suicide attempt status, controlling for key covariates. No associations were found between suicide attempts and other distinct sleep problems, including falling asleep at bedtime, sleeping a lot during the day, trouble waking up in the morning, sleep duration, and parent-reported nightmares. Clinicians should be aware of sleep problems as potential risk factors for suicide attempts for adolescents.

  1. Opioid system genes in alcoholism: a case-control study in Croatian population.

    PubMed

    Cupic, B; Stefulj, J; Zapletal, E; Matosic, A; Bordukalo-Niksic, T; Cicin-Sain, L; Gabrilovac, J

    2013-10-01

    Due to their involvement in dependence pathways, opioid system genes represent strong candidates for association studies investigating alcoholism. In this study, single nucleotide polymorphisms within the genes for mu (OPRM1) and kappa (OPRK1) opioid receptors and precursors of their ligands - proopiomelanocortin (POMC), coding for beta-endorphin and prodynorphin (PDYN) coding for dynorphins, were analyzed in a case-control study that included 354 male alcohol-dependent and 357 male control subjects from Croatian population. Analysis of allele and genotype frequencies of the selected polymorphisms of the genes OPRM1/POMC and OPRK1/PDYN revealed no differences between the tested groups. The same was true when alcohol-dependent persons were subdivided according to the Cloninger's criteria into type-1 and type-2 groups, known to differ in the extent of genetic control. Thus, the data obtained suggest no association of the selected polymorphisms of the genes OPRM1/POMC and OPRK1/PDYN with alcoholism in Croatian population.

  2. Case-control study of possible causative factors in mycosis fungoides

    SciTech Connect

    Tuyp, E.; Burgoyne, A.; Aitchison, T.; MacKie, R.

    1987-02-01

    A detailed case control study was carried out on 53 patients (33 males and 20 females) with histologically proven mycosis fungoides and on an age- and sex-matched control population. Possible causative factors investigated included occupation, recreation, and exposure to petrochemicals, pesticides, insecticides, and potential carcinogens. Exposure to plants of the Compositae family, tanning history, and chronic sun exposure were also investigated, as were smoking history, drug ingestion history, and other skin disease. Personal and family histories of other malignancies were also investigated. The only statistically significant difference to emerge was that the patients with mycosis fungoides had significantly more family history of atopic dermatitis. In view of the absence of any significant difference between patients and controls with regard to personal history of atopic dermatitis, this difference may be the result of multiple statistical testing rather than a phenomenon of true biological significance.

  3. Statin use and risk of glioma: population-based case-control analysis.

    PubMed

    Seliger, Corinna; Meier, Christoph Rudolf; Becker, Claudia; Jick, Susan Sara; Bogdahn, Ulrich; Hau, Peter; Leitzmann, Michael Fred

    2016-09-01

    Statins have been reported to decrease the incidence of cancer, but the risk of glioma among statin users has been investigated in only two prior observational studies, both of them suggesting a modest protective effect of statins. We conducted a matched case-control study using data from the UK-based Clinical Practice Research Datalink to analyse use of statins among 2469 cases with glioma and 24,690 controls. We performed conditional logistic regression analysis to calculate relative risks, estimated as odds ratios (ORs) with 95 % confidence intervals (CIs) adjusting for multiple confounding factors. As compared with non-use of statins, use of statins was not associated with risk of glioma (OR for ≥90 prescriptions=0.75; 95 % CI 0.48-1.17). Our findings do not support previous sparse evidence of a possible inverse association between statin use and glioma risk. PMID:27041698

  4. Environmental sanitation conditions and health impact: a case-control study.

    PubMed

    Heller, Léo; Colosimo, Enrico Antonio; Antunes, Carlos Mauricio de Figueiredo

    2003-01-01

    This epidemiological investigation examines the impact of several environmental sanitation conditions and hygiene practices on diarrhea occurrence among children under five years of age living in an urban area. The case-control design was employed; 997 cases and 999 controls were included in the investigation. Cases were defined as children with diarrhea and controls were randomly selected among children under five years of age. After logistic regression adjustment, the following variables were found to be significantly associated with diarrhea: washing and purifying fruit and vegetables; presence of wastewater in the street; refuse storage, collection and disposal; domestic water reservoir conditions; feces disposal from swaddles; presence of vectors in the house and flooding in the lot. The estimates of the relative risks reached values up to 2.87. The present study revealed the feasibility of developing and implementing an adequate model to establish intervention priorities in the field of environmental sanitation. PMID:12715062

  5. Case-control study of diesel exhaust exposure and bladder cancer

    SciTech Connect

    Wynder, E.L.; Dieck, G.S.; Hall, N.E.L.; Lahti, H.

    1985-08-01

    The relationship between bladder cancer and employment in occupations involving exposure to diesel exhaust was examined using data from a hospital-based case-control study of men aged 20 to 80 years in 18 hospitals in six US cities, from January 1981 to May 1983. In this analysis, 194 cases and 582 controls were compared according to occupation, smoking history, alcohol and coffee consumption, and various demographic variables. No difference was found in the proportion of bladder cancer cases employed in occupations with exposure to diesel exhaust compared to controls. This relationship did not change after taking smoking habits into account. Bladder cancer cases were significantly more likely to be current smokers of cigarettes than were controls.

  6. Tap or bottled water consumption and spontaneous abortion: a 1986 case-control study in California.

    PubMed

    Windham, G C; Swan, S H; Fenster, L; Neutra, R R

    1992-03-01

    To investigate whether drinking tap or bottled water during pregnancy affects the risk of spontaneous abortion, we asked questions about water consumption in a large case-control study (626 cases, 1,300 controls). The study ascertained cases from hospital pathology laboratory reports of pregnancies that began in 1986 and obtained controls from birth certificates. The crude odds ratio for consumption of any vs no cold tapwater at home during the first trimester was 1.2 (95% confidence interval = 1.0-1.5), with no dose-response effect. The crude odds ratio for any bottled water consumption was 0.79 (95% confidence interval = 0.65-0.96), with a downward trend by amount consumed. Adjusting for many potential confounders did not alter these associations appreciably, although some variables appeared to be effect modifiers. The point estimates were stronger among women who were more difficult to contact, suggesting the possibility of bias. PMID:1576215

  7. Environmental sanitation conditions and health impact: a case-control study.

    PubMed

    Heller, Léo; Colosimo, Enrico Antonio; Antunes, Carlos Mauricio de Figueiredo

    2003-01-01

    This epidemiological investigation examines the impact of several environmental sanitation conditions and hygiene practices on diarrhea occurrence among children under five years of age living in an urban area. The case-control design was employed; 997 cases and 999 controls were included in the investigation. Cases were defined as children with diarrhea and controls were randomly selected among children under five years of age. After logistic regression adjustment, the following variables were found to be significantly associated with diarrhea: washing and purifying fruit and vegetables; presence of wastewater in the street; refuse storage, collection and disposal; domestic water reservoir conditions; feces disposal from swaddles; presence of vectors in the house and flooding in the lot. The estimates of the relative risks reached values up to 2.87. The present study revealed the feasibility of developing and implementing an adequate model to establish intervention priorities in the field of environmental sanitation.

  8. Sociodemographic characteristics of domestic violence in China: a population case-control study.

    PubMed

    Cao, YuPing; Yang, ShiChang; Wang, GuoQiang; Zhang, YaLin

    2014-03-01

    A population case-control study of domestic violence in China was conducted to examine the relationship between individual- and household-level characteristics and violence perpetration and victimization. Demographic comparisons were conducted between perpetrators and victims (n = 624), perpetrators and matched controls (n = 628), and perpetrator households and control households (n = 620). A multivariate model of demographic risk was tested, integrating individual- and household-level correlates of violence perpetration. Compared with victims, perpetrators were more likely to be older, male, and have lower levels of education. In the final model, violence perpetration was more likely among individuals who earned more income, contributed a lower proportion of the household income, had a family member who was unemployed or lived in households with an authoritarian or independent power structure. PMID:24176988

  9. On an extended interpretation of linkage disequilibrium in genetic case-control association studies.

    PubMed

    Dickhaus, Thorsten; Stange, Jens; Demirhan, Haydar

    2015-11-01

    We are concerned with statistical inference for 2 × C × K contingency tables in the context of genetic case-control association studies. Multivariate methods based on asymptotic Gaussianity of vectors of test statistics require information about the asymptotic correlation structure among these test statistics under the global null hypothesis. In the case of C=2, we show that for a wide variety of test statistics this asymptotic correlation structure is given by the standardized linkage disequilibrium matrix of the K loci under investigation. Three popular choices of test statistics are discussed for illustration. In the case of C=3, the standardized composite linkage disequilibrium matrix is the limiting correlation matrix of the K locus-specific Cochran-Armitage trend test statistics.

  10. Case-controlled study of nursing home residents referred for treatment of vocally disruptive behavior.

    PubMed

    Draper, B; Snowdon, J; Meares, S; Turner, J; Gonski, P; McMinn, B; McIntosh, H; Latham, L; Draper, D; Luscombe, G

    2000-09-01

    The aim of this study was to identify factors associated with vocally disruptive behavior (VDB) in nursing home patients referred to aged care services for treatment, using a case-control methodology. Characteristics of the VDB, reasons for referral, perceived causal factors, and psychotropic use were noted. Twenty-five subjects and controls were examined with the Screaming Behavior Mapping Instrument, the Cornell Scale for Depression in Dementia, the Dementia Behavior Disturbance Scale, and measures of cognition, functional capacity, social activities, and emotional reactions of nursing staff. VDB was associated with other disturbed behaviors, depression, anxiety, severe dementia, functional impairment, communication difficulties, use of psychotropic medication, social isolation, and emotional distress in the nursing staff. Reasons for referral may relate more to the stress experienced by nursing home staff in managing VDB than to specific attributes of the VDB itself. PMID:11081953

  11. Risk factors for Enterobacter septicemia in a neonatal unit: case-control study.

    PubMed

    Fok, T F; Lee, C H; Wong, E M; Lyon, D J; Wong, W; Ng, P C; Cheung, K L; Cheng, A F

    1998-11-01

    Thirty cases of Enterobacter aerogenes or Enterobacter cloacae septicemia diagnosed over a 32-month period in a tertiary care neonatal unit were enrolled in a case-control study. Each case patient was matched with two controls (patients occupying the cots nearest the case patient when the latter developed septicemia). Of the 32 perinatal characteristics evaluated, 11 were identified by univariate analysis to be significantly associated with the infection. These included parents being residents of the Vietnamese refugee camps, respiratory distress syndrome, necrotizing enterocolitis, umbilical arterial catheterization, umbilical venous catheterization, bladder catheterization, mechanical ventilation, antibiotic treatment, peripheral venous catheterization, nasogastric intubation, and parenteral nutrition. Multivariate analysis, however, showed that preceding bladder catheterization and ongoing parenteral nutrition were the only independent risk factors for enterobacter septicemia. Strict aseptic technique in the preparation of parenteral nutrition fluid and avoidance of bladder catheterization are measures that may reduce the risk of enterobacter sepsis for newborns.

  12. Case-control study of environmental risk factors for Parkinson's disease in Belgium.

    PubMed

    Pals, Philippe; Van Everbroeck, Bart; Grubben, Bart; Viaene, Maria Kristina; Dom, René; van der Linden, Chris; Santens, Patrick; Martin, Jean Jacques; Cras, Patrick

    2003-01-01

    The aetiology of Parkinson's disease (PD) is unknown and said to be multifactorial. We report on a retrospective epidemiological case control study, performed in Flanders during a 3-year period, investigating known and potential environmental risk factors for PD by means of questionnaires. We investigated 423 prevalent patients and 205 spouse-controls. We found familial occurrence in 15% of the patients, a mean age of onset of 58 years, and a clear male preponderance (male/female ratio 1.53). Our results suggest more nulliparity among female PD patients (95% CI: 1.08-5.76). We found a discrete clustering of patients in areas with intensive metallurgic frequently employed in metallurgy than controls (95% CI: 1.04-9.20). Furthermore, patients were clearly more exposed to zinc (95% CI: 1.51-90.90) and toluene (95% CI: 1.03 58.82). Male patients report more prostatectomy-surgery (95% CI: 1.54-17.24).

  13. Tap or bottled water consumption and spontaneous abortion: a 1986 case-control study in California.

    PubMed

    Windham, G C; Swan, S H; Fenster, L; Neutra, R R

    1992-03-01

    To investigate whether drinking tap or bottled water during pregnancy affects the risk of spontaneous abortion, we asked questions about water consumption in a large case-control study (626 cases, 1,300 controls). The study ascertained cases from hospital pathology laboratory reports of pregnancies that began in 1986 and obtained controls from birth certificates. The crude odds ratio for consumption of any vs no cold tapwater at home during the first trimester was 1.2 (95% confidence interval = 1.0-1.5), with no dose-response effect. The crude odds ratio for any bottled water consumption was 0.79 (95% confidence interval = 0.65-0.96), with a downward trend by amount consumed. Adjusting for many potential confounders did not alter these associations appreciably, although some variables appeared to be effect modifiers. The point estimates were stronger among women who were more difficult to contact, suggesting the possibility of bias.

  14. Nutritional status of children with autism spectrum disorders (ASDs): a case-control study.

    PubMed

    Marí-Bauset, Salvador; Llopis-González, Agustín; Zazpe-García, Itziar; Marí-Sanchis, Amelia; Morales-Suárez-Varela, María

    2015-01-01

    Children with autism spectrum disorder (ASD) have problems of food selectivity, implying risks of nutritional deficiencies. The aim was to compare intakes of macro and micronutrients and body mass index in ASD and typically developing (TD) children. In a case-control study, 3-day food diaries and anthropometric measurements were completed for ASD (n = 40) and TD (n = 113) children (aged 6-10 years) living in the same area. Body mass indices were below the 5th percentile in 20 % of ASD versus 8.85% of TD children. We found intakes were lower for fluoride (p = 0.017) and higher for vitamin E (p = 0.001). There was limited food variety and inadequacy of some intakes suggests that routine monitoring of ASD children should include assessment of their dietary habits, as well as anthropometric measurements.

  15. [The athlete's heart: an echocardiographic case-control study on Senegalese athletes].

    PubMed

    Doumbia, A S; Diallo, T A; Kane, A; Diao, M; Diop, I B; Sarr, M; Ba, S A; Diouf, S M

    2003-01-01

    The aim of this work is to study the echocardiographic parameters of male trained athletes. It is about a case-control study comparing 3 groups: basketball players, cyclists and not sports healthy subjects. All the subjects benefited from an echocardiography (time motion, two-dimensional and pulse Doppler). The mean age is of 23.5 years for the cyclists group, 24 years for the basketball players and of 26.2 years for the control group. Compared with the control group, the left ventricular telediastolic dimensions, left ventricular mass index and the pulmonary flow velocity are higher in athletes group. The basketball players have a higher left ventricular diameter and parameter of systolic function than cyclists group. The septal diameter is higher in the cyclists group. This study finds some differencies in Senegalese athletes in the characteristics of the standard athletic heart syndrome.

  16. ICA-based artifact removal diminishes scan site differences in multi-center resting-state fMRI.

    PubMed

    Feis, Rogier A; Smith, Stephen M; Filippini, Nicola; Douaud, Gwenaëlle; Dopper, Elise G P; Heise, Verena; Trachtenberg, Aaron J; van Swieten, John C; van Buchem, Mark A; Rombouts, Serge A R B; Mackay, Clare E

    2015-01-01

    Resting-state fMRI (R-fMRI) has shown considerable promise in providing potential biomarkers for diagnosis, prognosis and drug response across a range of diseases. Incorporating R-fMRI into multi-center studies is becoming increasingly popular, imposing technical challenges on data acquisition and analysis, as fMRI data is particularly sensitive to structured noise resulting from hardware, software, and environmental differences. Here, we investigated whether a novel clean up tool for structured noise was capable of reducing center-related R-fMRI differences between healthy subjects. We analyzed three Tesla R-fMRI data from 72 subjects, half of whom were scanned with eyes closed in a Philips Achieva system in The Netherlands, and half of whom were scanned with eyes open in a Siemens Trio system in the UK. After pre-statistical processing and individual Independent Component Analysis (ICA), FMRIB's ICA-based X-noiseifier (FIX) was used to remove noise components from the data. GICA and dual regression were run and non-parametric statistics were used to compare spatial maps between groups before and after applying FIX. Large significant differences were found in all resting-state networks between study sites before using FIX, most of which were reduced to non-significant after applying FIX. The between-center difference in the medial/primary visual network, presumably reflecting a between-center difference in protocol, remained statistically significant. FIX helps facilitate multi-center R-fMRI research by diminishing structured noise from R-fMRI data. In doing so, it improves combination of existing data from different centers in new settings and comparison of rare diseases and risk genes for which adequate sample size remains a challenge. PMID:26578859

  17. Low intensity vs. self-guided Internet-delivered psychotherapy for major depression: a multicenter, controlled, randomized study

    PubMed Central

    2013-01-01

    Background Major depression will become the second most important cause of disability in 2020. Computerized cognitive-behaviour therapy could be an efficacious and cost-effective option for its treatment. No studies on cost-effectiveness of low intensity vs self-guided psychotherapy has been carried out. The aim of this study is to assess the efficacy of low intensity vs self-guided psychotherapy for major depression in the Spanish health system. Methods The study is made up of 3 phases: 1.- Development of a computerized cognitive-behaviour therapy for depression tailored to Spanish health system. 2.- Multicenter controlled, randomized study: A sample (N=450 patients) with mild/moderate depression recruited in primary care. They should have internet availability at home, not receive any previous psychological treatment, and not suffer from any other severe somatic or psychological disorder. They will be allocated to one of 3 treatments: a) Low intensity Internet-delivered psychotherapy + improved treatment as usual (ITAU) by GP, b) Self-guided Internet-delivered psychotherapy + ITAU or c) ITAU. Patients will be diagnosed with MINI psychiatric interview. Main outcome variable will be Beck Depression Inventory. It will be also administered EuroQol 5D (quality of life) and Client Service Receipt Inventory (consume of health and social services). Patients will be assessed at baseline, 3 and 12 months. An intention to treat and a per protocol analysis will be performed. Discussion The comparisons between low intensity and self-guided are infrequent, and also a comparative economic evaluation between them and compared with usual treatment in primary. The strength of the study is that it is a multicenter, randomized, controlled trial of low intensity and self-guided Internet-delivered psychotherapy for depression in primary care, being the treatment completely integrated in primary care setting. Trial registration Clinical Trials NCT01611818 PMID:23312003

  18. Dietary patterns, food groups and myocardial infarction: a case-control study.

    PubMed

    Lockheart, Michael S K; Steffen, Lyn M; Rebnord, Hege Møklebust; Fimreite, Ragnhild Lekven; Ringstad, Jetmund; Thelle, Dag S; Pedersen, Jan I; Jacobs, David R

    2007-08-01

    Certain dietary patterns may be related to the risk of CVD. We hypothesised that a plant-centred dietary pattern would be associated with a reduced risk of first myocardial infarction (MI). A case-control study of Norwegian men and postmenopausal women (age 45-75 years) was performed. A FFQ was administered, generally within 3 d after incident MI (n 106 cases). Controls (n 105) were frequency matched on sex, age and geographic location. On the FFQ, 190 items were categorised into thirty-five food groups and an a priori healthy diet pattern score was created. We estimated OR using logistic regression with adjustment for energy intake, family history of heart disease, marital status, current smoking, education and age. Among food groups, the risk of MI was significantly higher per SD of butter and margarine (OR 1.66 (95 % CI 1.12, 2.46)), and lower per SD of tomatoes (OR 0.53 (95 % CI 0.35, 0.79)), high-fat fish (OR 0.57 (95 % CI 0.38, 0.86)), wine (OR 0.58 (95 % CI 0.41, 0.83)), salad (OR 0.59 (95 % CI 0.40, 0.87)), whole grain breakfast cereals (OR 0.64 (95 % CI 0.45, 0.90)), cruciferous vegetables (OR 0.66 (95 % CI 0.47, 0.93)) and non-hydrogenated vegetable oil (OR 0.68 (95 % CI 0.49, 0.95)). An abundance of cases were found to have a low a priori healthy diet pattern score. A dietary pattern emphasising nutrient-rich plant foods and high-fat fish and low in trans fatty acids was associated with decreased risk of MI among Norwegians.

  19. Influence of social factors on avoidable mortality: a hospital-based case-control study.

    PubMed Central

    Bautista, Daniel; Alfonso, José Luis; Corella, Dolores; Saiz, Carmen

    2005-01-01

    OBJECTIVE: The effect of socioeconomic factors on avoidable mortality at an individual level is not well known, since most studies showing this association are based on aggregate data. The purpose of this study was to determine socioeconomic differences between those patients who die of avoidable causes and those who do not die. METHODS: A matched case-control study was carried out regarding in-hospital avoidable mortality (Holland's medical care indicators) that occurred in a university hospital serving a Spanish-Mediterranean population during a 30-month period. RESULTS: We studied 82 cases of death from avoidable causes and 300 controls matched on medical care indicators and age. The variables that showed a statistically significant association with in-hospital avoidable mortality were number of diagnoses (the greater the number, the higher the risk), length of stay (patients staying seven or more days presented a lower risk), and education. Those patients with low and middle educational levels showed a greater risk of avoidable mortality (adjusted odds ratio=3.57 and 2.82, respectively) than those patients with higher levels of education. CONCLUSIONS: Consistent with the findings of studies based on aggregate data, our case-control analyses indicated that among several socioeconomic variables studied, educational level was significantly associated with the risk of in-hospital avoidable mortality, regardless of age and medical care indicators. Patients with low levels of education (<6 years of schooling) were at highest risk for in-hospital avoidable mortality, followed by those with middle levels of education (7-10 years of schooling). PMID:15736332

  20. Alcohol and Difficulty Conceiving in the SUN Cohort: A Nested Case-Control Study

    PubMed Central

    Lopez-del Burgo, Cristina; Gea, Alfredo; de Irala, Jokin; Martínez-González, Miguel A.; Chavarro, Jorge E.; Toledo, Estefania

    2015-01-01

    The role of alcohol on fertility remains unclear. We aimed to investigate the association between alcohol and specific alcoholic beverages consumption and the risk of difficulty getting pregnant. We used a case-control study nested within the Seguimiento Universidad de Navarra (SUN) cohort, a prospective, dynamic and multipurpose cohort of 21,705 Spanish university graduates, followed biennially with mailed questionnaires. We identified 686 case-control pairs, matched for age and time in the cohort. Cases were women reporting difficulty getting pregnant. Controls did not consult due to difficulty conceiving and had at least one child during follow-up. After adjustment for potential confounders, we found no association between self-reported difficulty getting pregnant and the number of alcoholic beverages consumed per week, (Odds Ratio [OR] > 5 drinks/week vs. none = 1.04, 95% Confidence Interval [CI] = 0.72–1.51). No association between types of alcoholic beverage and difficulty conceiving (OR > 5 drinks of wine/week vs. none = 1.16, 95% CI = 0.72–1.88; OR > 5 drinks of beer/week vs. none = 1.06, 95% CI = 0.82–1.37; OR > 5 drinks of spirits/week vs. none = 1.24, 95% CI = 0.84–1.64) was observed. In conclusion, we found no association between alcohol intake and risk of consulting a physician due to difficulty conceiving. More studies are needed to clearly elucidate the effects of alcohol intake on women’s fertility. In the meantime, recommendations about alcohol intake to couples trying to conceive have to be given cautiously. PMID:26225997

  1. High Seroprevalence of Leptospira Exposure in Meat Workers in Northern Mexico: A Case-Control Study

    PubMed Central

    Alvarado-Esquivel, Cosme; Hernandez-Tinoco, Jesus; Sanchez-Anguiano, Luis Francisco; Ramos-Nevarez, Agar; Cerrillo-Soto, Sandra Margarita; Saenz-Soto, Leandro; Martinez-Ramirez, Lucio

    2016-01-01

    Background The seroepidemiology of Leptospira infection in workers occupationally exposed to raw meat has been poorly studied. This work aimed to determine the association between Leptospira exposure and the occupation of meat worker, and to determine the seroprevalence association with socio-demographic, work, clinical and behavioral characteristics of the meat workers studied. Methods We performed a case-control study in 124 meat workers and 124 age- and gender-matched control subjects in Durango City, Mexico. Sera of cases and controls were analyzed for anti-Leptospira IgG antibodies using a commercially available enzyme immunoassay. Data of meat workers were obtained with the aid of a questionnaire. The association of Leptospira exposure with the characteristics of meat workers was analyzed by bivariate and multivariate analyses. Results Anti-Leptospira IgG antibodies were found in 22 (17.7%) of 124 meat workers and in eight (6.5%) of 124 controls (OR = 3.12; 95% CI: 1.33 - 7.33; P = 0.006). Seroprevalence of Leptospira infection was similar between male butchers (17.6%) and female butchers (18.2%) (P = 1.00). Multivariate analysis of socio-demographic, work and behavioral variables showed that Leptospira exposure was associated with duration in the activity, rural residence, and consumption of snake meat and unwashed raw fruits. Conclusions This is the first case-control study of the association of Leptospira exposure with the occupation of meat worker. Results indicate that meat workers represent a risk group for Leptospira exposure. Risk factors for Leptospira exposure found in this study may help in the design of optimal preventive measures against Leptospira infection. PMID:26858797

  2. Alcohol and Difficulty Conceiving in the SUN Cohort: A Nested Case-Control Study.

    PubMed

    Lopez-del Burgo, Cristina; Gea, Alfredo; de Irala, Jokin; Martínez-González, Miguel A; Chavarro, Jorge E; Toledo, Estefania

    2015-07-27

    The role of alcohol on fertility remains unclear. We aimed to investigate the association between alcohol and specific alcoholic beverages consumption and the risk of difficulty getting pregnant. We used a case-control study nested within the Seguimiento Universidad de Navarra (SUN) cohort, a prospective, dynamic and multipurpose cohort of 21,705 Spanish university graduates, followed biennially with mailed questionnaires. We identified 686 case-control pairs, matched for age and time in the cohort. Cases were women reporting difficulty getting pregnant. Controls did not consult due to difficulty conceiving and had at least one child during follow-up. After adjustment for potential confounders, we found no association between self-reported difficulty getting pregnant and the number of alcoholic beverages consumed per week, (Odds Ratio [OR] > 5 drinks/week vs. none = 1.04, 95% Confidence Interval [CI] = 0.72-1.51). No association between types of alcoholic beverage and difficulty conceiving (OR > 5 drinks of wine/week vs. none = 1.16, 95% CI = 0.72-1.88; OR > 5 drinks of beer/week vs. none = 1.06, 95% CI = 0.82-1.37; OR > 5 drinks of spirits/week vs. none = 1.24, 95% CI = 0.84-1.64) was observed. In conclusion, we found no association between alcohol intake and risk of consulting a physician due to difficulty conceiving. More studies are needed to clearly elucidate the effects of alcohol intake on women's fertility. In the meantime, recommendations about alcohol intake to couples trying to conceive have to be given cautiously.

  3. Tubal ligation, hysterectomy, and epithelial ovarian cancer in the New England Case-Control Study

    PubMed Central

    Rice, Megan S.; Murphy, Megan A.; Vitonis, Allison F.; Cramer, Daniel W.; Titus, Linda J.; Tworoger, Shelley S.; Terry, Kathryn L.

    2013-01-01

    Previous studies have observed that tubal ligation and hysterectomy are associated with a decreased risk of ovarian cancer; however little is known about whether these associations vary bysurgical characteristics, individual characteristics, or tumor histology. We used logistic regression to examine tubal ligation, simple hysterectomy, and hysterectomy with unilateral oophorectomy in relation to risk of epithelial ovarian cancer in the New England Case-Control study. Our primary analysis included 2,265 cases and 2,333 controls. Overall, tubal ligation was associated with a lower risk of epithelial ovarian cancer (OR: 0.82, 95%CI: 0.68-0.97), especially for endometrioid tumors (OR=0.45, 95%CI: 0.29-0.69). The inverse association between tubal ligation and ovarian cancer risk was stronger for women who had undergone the procedure at the time of last delivery (OR=0.60, 95%CI: 0.42-0.84) rather than at a later time (OR=0.93, 95%CI: 0.75-1.15). Overall, simple hysterectomy was not associated with ovarian cancer risk (OR: 1.09, 95%CI: 0.83, 1.42), although it was associated with a non-significant decreased risk of ovarian cancer among women who underwent the procedure at age 45 or older (RR: 0.64, 95%CI: 0.40, 1.02) or within the last 10 years (OR=0.65, 95%CI: 0.38, 1.13). Overall, women who had a hysterectomy with a unilateral oophorectomy had significantly lower risk of ovarian cancer (OR=0.65, 95%CI: 0.45-0.94). In summary, tubal ligation and hysterectomy with unilateral oophorectomy were inversely associated with ovarian cancer risk in a large population-based case-control study. Additional research is necessary to understand the potential biologic mechanisms by which these procedures may reduce ovarian cancer risk. PMID:23650079

  4. Outcome of liver transplantation in patients with diabetes mellitus: a case-control study.

    PubMed

    John, P R; Thuluvath, P J

    2001-11-01

    The influence of preexisting diabetes mellitus (DM) on outcome after orthotopic liver transplantation (OLT) has not been well defined. The objective of our study was to compare the morbidity and mortality after OLT in 57 patients with preexisting DM (3 type I, 54 type II) with 114 age-, sex-, and race-matched patients without DM (case controls). The demographics were similar in both groups. Pretransplantation serum creatinine was significantly higher in the diabetic group compared with case controls. The incidence of the following complications was significantly higher in the diabetic group after OLT: cardiovascular (61.4% vs. 21.9%, P <.001), major (54.4% vs. 29.8%, P =.002) and minor infections (29.8% vs. 7.9%, P <.0001), renal (59.7% vs. 20.2%, P <.001), ophthalmologic (10.5% vs. 0.9%, P =.01), respiratory (24.6% vs. 7.0%, P =.001), neurologic (31.6% vs. 7.0%, P <.001), hematologic (19.3% vss 2.6%, P =.001), musculoskeletal (24.6% vs. 5.3%, P =.001), and malignancy (22.8% vs. 10.5%, P =.03). The duration of hospital stay, cost of hospitalization, retransplantation, and overall graft survival were similar. Acute rejection was seen in 50.9% of diabetics compared with 25.4% in controls (P =.0009). One-year (87% vs. 77%) and 2-year (81.6% vs. 70.1%) patient survival was similar, but 5-year survival was lower in the DM group (34.4% vs. 67.7%, P =.002). In conclusion, preexisting diabetes is associated with a significant post-OLT morbidity and mortality, and our observations suggest that patients with DM warrant more rigorous pre- and post-OLT evaluation. PMID:11679959

  5. Validation of a home safety questionnaire used in a series of case-control studies

    PubMed Central

    Watson, Michael; Benford, Penny; Coupland, Carol; Clacy, Rose; Hindmarch, Paul; Majsak-Newman, Gosia; Deave, Toity; Kendrick, Denise

    2014-01-01

    Objective To measure the validity of safety behaviours, safety equipment use and hazards reported on a questionnaire by parents/carers with children aged under 5 years participating in a series of home safety case-control studies. Methods The questionnaire measured safety behaviours, safety equipment use and hazards being used as exposures in five case-control studies. Responses to questions were compared with observations made during a home visit. The researchers making observations were blind to questionnaire responses. Results In total, 162 families participated in the study. Overall agreement between reported and observed values of the safety practices ranged from 48.5% to 97.3%. Only 3 safety practices (stair gate at the top of stairs, stair gate at the bottom of stairs, stairs are carpeted) had substantial agreement based on the κ statistic (k=0.65, 0.72, 0.74, respectively). Sensitivity was high (≥70%) for 19 of the 30 safety practices, and specificity was high (≥70%) for 20 of the 30 practices. Overall for 24 safety practices, a higher proportion of respondents over-reported than under-reported safe practice (negative predictive value>positive predictive value). For six safety practices, a higher proportion of respondents under-reported than over-reported safe practice (negative predictive value

  6. Risk factors of multiple system atrophy: a case-control study in French patients.

    PubMed

    Vidal, Jean-Sébastien; Vidailhet, Marie; Elbaz, Alexis; Derkinderen, Pascal; Tzourio, Christophe; Alpérovitch, Annick

    2008-04-30

    Multiple system atrophy (MSA) is a rare sporadic progressive neurodegenerative disorder. MSA risk factors are poorly known. The objectives of this case-control study were to study environmental risk factors associated with MSA. Cases were recruited through five French referral centers. Controls matched for age, gender, and living area were recruited from healthy relatives of inpatients free of any parkinsonian syndrome of the same centers. Subjects were interviewed about exposure to environmental factors (pesticides, solvents, etc.), occupation and food habits, and use of anti-inflammatory drugs. Odds ratios and 95% confident intervals (OR [95% CI]) were computed using conditional logistic regression. Seventy-one cases and 71 matched controls were included. Low education level was more frequent in cases than in controls. Controls drank more alcohol than did cases (OR = 0.5 [0.2-1.1]) and the risk of MSA decreased with increasing alcohol consumption (P = 0.04). Controls ate fish and sea food more often and drank more tea than cases. Aspirin intake was more frequent among controls than did cases (OR = 0.5 [0.2-1.0]) and the risk of MSA decreased with the frequency of intake (P = 0.0002). MSA was not associated to exposure to pesticides, solvents, and other toxics neither to occupations, except plant and machine operators and assemblers (OR = 10.0 [2.1-47.5]) where the risk of MSA increased with number of years in this occupation (P = 0.004). This case-control study provided new findings about risk factors of MSA. On another hand, it did not confirm the previously reported association between MSA and exposure to pesticides.

  7. Stevens-Johnson Syndrome Associated with Drugs and Vaccines in Children: A Case-Control Study

    PubMed Central

    Raucci, Umberto; Rossi, Rossella; Da Cas, Roberto; Rafaniello, Concita; Mores, Nadia; Bersani, Giulia; Reale, Antonino; Pirozzi, Nicola; Menniti-Ippolito, Francesca; Traversa, Giuseppe; in Drug and Children, Italian Multicenter Study Group for Vaccine Safety

    2013-01-01

    Objective Stevens-Johnson Syndrome (SJS) is one of the most severe muco-cutaneous diseases and its occurrence is often attributed to drug use. The aim of the present study is to quantify the risk of SJS in association with drug and vaccine use in children. Methods A multicenter surveillance of children hospitalized through the emergency departments for acute conditions of interest is currently ongoing in Italy. Cases with a diagnosis of SJS were retrieved from all admissions. Parents were interviewed on child’s use of drugs and vaccines preceding the onset of symptoms that led to the hospitalization. We compared the use of drugs and vaccines in cases with the corresponding use in a control group of children hospitalized for acute neurological conditions. Results Twenty-nine children with a diagnosis of SJS and 1,362 with neurological disorders were hospitalized between 1st November 1999 and 31st October 2012. Cases were more frequently exposed to drugs (79% vs 58% in the control group; adjusted OR 2.4; 95% CI 1.0–6.1). Anticonvulsants presented the highest adjusted OR: 26.8 (95% CI 8.4–86.0). Significantly elevated risks were also estimated for antibiotics use (adjusted OR 3.3; 95% CI 1.5–7.2), corticosteroids (adjusted OR 4.2; 95% CI 1.8–9.9) and paracetamol (adjusted OR 3.2; 95% CI 1.5–6.9). No increased risk was estimated for vaccines (adjusted OR: 0.9; 95% CI 0.3–2.8). Discussion Our study provides additional evidence on the etiologic role of drugs and vaccines in the occurrence of SJS in children. PMID:23874553

  8. Coordination and management of multicenter clinical studies in trauma: Experience from the PRospective Observational Multicenter Major Trauma Transfusion (PROMMTT) Study

    PubMed Central

    Rahbar, Mohammad H.; Fox, Erin E.; del Junco, Deborah J.; Cotton, Bryan A.; Podbielski, Jeanette M.; Matijevic, Nena; Cohen, Mitchell J.; Schreiber, Martin A.; Zhang, Jiajie; Mirhaji, Parsa; Duran, Sarah; Reynolds, Robert J.; Benjamin-Garner, Ruby; Holcomb, John B.

    2011-01-01

    Aim Early death due to hemorrhage is a major consequence of traumatic injury. Transfusion practices differ among hospitals and it is unknown which transfusion practices improve survival. This report describes the experience of the PRospective Observational Multicenter Major Trauma Transfusion (PROMMTT) Study Data Coordination Center in designing and coordinating a study to examine transfusion practices at ten Level 1 trauma centers in the U.S. Methods PROMMTT was a multisite prospective observational study of severely injured transfused trauma patients. The clinical sites collected real-time information on the timing and amounts of blood product infusions as well as colloids and crystalloids, vital signs, initial diagnostic and clinical laboratory tests, life saving interventions and other clinical care data. Results Between July 2009 and October 2010, PROMMTT screened 12,561 trauma admissions and enrolled 1,245 patients who received one or more blood transfusions within 6 hours of ED admission. A total of 297 massive transfusions were observed over the course of the study at a combined rate of 5.0 massive transfusion patients/week. Conclusion PROMMTT is the first multisite study to collect real-time prospective data on trauma patients requiring transfusion. Support from the Department of Defense and collaborative expertise from the ten participating centers helped to demonstrate the feasibility of prospective trauma transfusion studies. The observational data collected from this study will be an invaluable resource for research in trauma surgery and it will guide the design and conduct of future randomized trials. PMID:22001613

  9. The Relationship Between Distance to Water Source and Moderate-to-Severe Diarrhea in the Global Enterics Multi-Center Study in Kenya, 2008-2011.

    PubMed

    Nygren, Benjamin L; O'Reilly, Ciara E; Rajasingham, Anangu; Omore, Richard; Ombok, Maurice; Awuor, Alex O; Jaron, Peter; Moke, Fenny; Vulule, John; Laserson, Kayla; Farag, Tamer H; Nasrin, Dilruba; Nataro, James P; Kotloff, Karen L; Levine, Myron M; Derado, Gordana; Ayers, Tracy L; Lash, R Ryan; Breiman, Robert F; Mintz, Eric D

    2016-05-01

    In the developing world, fetching water for drinking and other household uses is a substantial burden that affects water quantity and quality in the household. We used logistic regression to examine whether reported household water fetching times were a risk factor for moderate-to-severe diarrhea (MSD) using case-control data of 3,359 households from the Global Enterics Multi-Center Study in Kenya in 2009-2011. We collected additional global positioning system (GPS) data for a subset of 254 randomly selected households and compared GPS-based straight line and actual travel path distances to fetching times reported by respondents. GPS-based data were highly correlated with respondent-provided times (Spearman correlation coefficient = 0.81, P < 0.0001). The median estimated one-way distance to water source was 200 m for cases and 171 for controls (Wilcoxon rank sums/Mann-Whitney P = 0.21). A round-trip fetching time of > 30 minutes was reported by 25% of cases versus 15% of controls and was significantly associated with MSD where rainwater was not used in the last 2 weeks (odds ratio = 1.97, 95% confidence interval = 1.56-2.49). These data support the United Nations definition of access to an improved water source being within 30 minutes total round-trip travel time. PMID:26928833

  10. The Relationship Between Distance to Water Source and Moderate-to-Severe Diarrhea in the Global Enterics Multi-Center Study in Kenya, 2008-2011.

    PubMed

    Nygren, Benjamin L; O'Reilly, Ciara E; Rajasingham, Anangu; Omore, Richard; Ombok, Maurice; Awuor, Alex O; Jaron, Peter; Moke, Fenny; Vulule, John; Laserson, Kayla; Farag, Tamer H; Nasrin, Dilruba; Nataro, James P; Kotloff, Karen L; Levine, Myron M; Derado, Gordana; Ayers, Tracy L; Lash, R Ryan; Breiman, Robert F; Mintz, Eric D

    2016-05-01

    In the developing world, fetching water for drinking and other household uses is a substantial burden that affects water quantity and quality in the household. We used logistic regression to examine whether reported household water fetching times were a risk factor for moderate-to-severe diarrhea (MSD) using case-control data of 3,359 households from the Global Enterics Multi-Center Study in Kenya in 2009-2011. We collected additional global positioning system (GPS) data for a subset of 254 randomly selected households and compared GPS-based straight line and actual travel path distances to fetching times reported by respondents. GPS-based data were highly correlated with respondent-provided times (Spearman correlation coefficient = 0.81, P < 0.0001). The median estimated one-way distance to water source was 200 m for cases and 171 for controls (Wilcoxon rank sums/Mann-Whitney P = 0.21). A round-trip fetching time of > 30 minutes was reported by 25% of cases versus 15% of controls and was significantly associated with MSD where rainwater was not used in the last 2 weeks (odds ratio = 1.97, 95% confidence interval = 1.56-2.49). These data support the United Nations definition of access to an improved water source being within 30 minutes total round-trip travel time.

  11. Post hoc Analysis for Detecting Individual Rare Variant Risk Associations Using Probit Regression Bayesian Variable Selection Methods in Case-Control Sequencing Studies.

    PubMed

    Larson, Nicholas B; McDonnell, Shannon; Albright, Lisa Cannon; Teerlink, Craig; Stanford, Janet; Ostrander, Elaine A; Isaacs, William B; Xu, Jianfeng; Cooney, Kathleen A; Lange, Ethan; Schleutker, Johanna; Carpten, John D; Powell, Isaac; Bailey-Wilson, Joan; Cussenot, Olivier; Cancel-Tassin, Geraldine; Giles, Graham; MacInnis, Robert; Maier, Christiane; Whittemore, Alice S; Hsieh, Chih-Lin; Wiklund, Fredrik; Catolona, William J; Foulkes, William; Mandal, Diptasri; Eeles, Rosalind; Kote-Jarai, Zsofia; Ackerman, Michael J; Olson, Timothy M; Klein, Christopher J; Thibodeau, Stephen N; Schaid, Daniel J

    2016-09-01

    Rare variants (RVs) have been shown to be significant contributors to complex disease risk. By definition, these variants have very low minor allele frequencies and traditional single-marker methods for statistical analysis are underpowered for typical sequencing study sample sizes. Multimarker burden-type approaches attempt to identify aggregation of RVs across case-control status by analyzing relatively small partitions of the genome, such as genes. However, it is generally the case that the aggregative measure would be a mixture of causal and neutral variants, and these omnibus tests do not directly provide any indication of which RVs may be driving a given association. Recently, Bayesian variable selection approaches have been proposed to identify RV associations from a large set of RVs under consideration. Although these approaches have been shown to be powerful at detecting associations at the RV level, there are often computational limitations on the total quantity of RVs under consideration and compromises are necessary for large-scale application. Here, we propose a computationally efficient alternative formulation of this method using a probit regression approach specifically capable of simultaneously analyzing hundreds to thousands of RVs. We evaluate our approach to detect causal variation on simulated data and examine sensitivity and specificity in instances of high RV dimensionality as well as apply it to pathway-level RV analysis results from a prostate cancer (PC) risk case-control sequencing study. Finally, we discuss potential extensions and future directions of this work.

  12. Selection of population controls for a Salmonella case-control study in the UK using a market research panel and web-survey provides time and resource savings.

    PubMed

    Mook, P; Kanagarajah, S; Maguire, H; Adak, G K; Dabrera, G; Waldram, A; Freeman, R; Charlett, A; Oliver, I

    2016-04-01

    Timely recruitment of population controls in infectious disease outbreak investigations is challenging. We evaluated the timeliness and cost of using a market research panel as a sampling frame for recruiting controls in a case-control study during an outbreak of Salmonella Mikawasima in the UK in 2013. We deployed a web-survey by email to targeted members of a market research panel (panel controls) in parallel to the outbreak control team interviewing randomly selected public health staff by telephone and completing paper-based questionnaires (staff controls). Recruitment and completion of exposure history web-surveys for panel controls (n = 123) took 14 h compared to 15 days for staff controls (n = 82). The average staff-time cost per questionnaire for staff controls was £13·13 compared to an invoiced cost of £3·60 per panel control. Differences in the distribution of some exposures existed between these control groups but case-control studies using each group found that illness was associated with consumption of chicken outside of the home and chicken from local butchers. Recruiting market research panel controls offers time and resource savings. More rapid investigations would enable more prompt implementation of control measures. We recommend that this method of recruiting controls is considered in future investigations and assessed further to better understand strengths and limitations.

  13. Post hoc Analysis for Detecting Individual Rare Variant Risk Associations Using Probit Regression Bayesian Variable Selection Methods in Case-Control Sequencing Studies.

    PubMed

    Larson, Nicholas B; McDonnell, Shannon; Albright, Lisa Cannon; Teerlink, Craig; Stanford, Janet; Ostrander, Elaine A; Isaacs, William B; Xu, Jianfeng; Cooney, Kathleen A; Lange, Ethan; Schleutker, Johanna; Carpten, John D; Powell, Isaac; Bailey-Wilson, Joan; Cussenot, Olivier; Cancel-Tassin, Geraldine; Giles, Graham; MacInnis, Robert; Maier, Christiane; Whittemore, Alice S; Hsieh, Chih-Lin; Wiklund, Fredrik; Catolona, William J; Foulkes, William; Mandal, Diptasri; Eeles, Rosalind; Kote-Jarai, Zsofia; Ackerman, Michael J; Olson, Timothy M; Klein, Christopher J; Thibodeau, Stephen N; Schaid, Daniel J

    2016-09-01

    Rare variants (RVs) have been shown to be significant contributors to complex disease risk. By definition, these variants have very low minor allele frequencies and traditional single-marker methods for statistical analysis are underpowered for typical sequencing study sample sizes. Multimarker burden-type approaches attempt to identify aggregation of RVs across case-control status by analyzing relatively small partitions of the genome, such as genes. However, it is generally the case that the aggregative measure would be a mixture of causal and neutral variants, and these omnibus tests do not directly provide any indication of which RVs may be driving a given association. Recently, Bayesian variable selection approaches have been proposed to identify RV associations from a large set of RVs under consideration. Although these approaches have been shown to be powerful at detecting associations at the RV level, there are often computational limitations on the total quantity of RVs under consideration and compromises are necessary for large-scale application. Here, we propose a computationally efficient alternative formulation of this method using a probit regression approach specifically capable of simultaneously analyzing hundreds to thousands of RVs. We evaluate our approach to detect causal variation on simulated data and examine sensitivity and specificity in instances of high RV dimensionality as well as apply it to pathway-level RV analysis results from a prostate cancer (PC) risk case-control sequencing study. Finally, we discuss potential extensions and future directions of this work. PMID:27312771

  14. Selection of population controls for a Salmonella case-control study in the UK using a market research panel and web-survey provides time and resource savings.

    PubMed

    Mook, P; Kanagarajah, S; Maguire, H; Adak, G K; Dabrera, G; Waldram, A; Freeman, R; Charlett, A; Oliver, I

    2016-04-01

    Timely recruitment of population controls in infectious disease outbreak investigations is challenging. We evaluated the timeliness and cost of using a market research panel as a sampling frame for recruiting controls in a case-control study during an outbreak of Salmonella Mikawasima in the UK in 2013. We deployed a web-survey by email to targeted members of a market research panel (panel controls) in parallel to the outbreak control team interviewing randomly selected public health staff by telephone and completing paper-based questionnaires (staff controls). Recruitment and completion of exposure history web-surveys for panel controls (n = 123) took 14 h compared to 15 days for staff controls (n = 82). The average staff-time cost per questionnaire for staff controls was £13·13 compared to an invoiced cost of £3·60 per panel control. Differences in the distribution of some exposures existed between these control groups but case-control studies using each group found that illness was associated with consumption of chicken outside of the home and chicken from local butchers. Recruiting market research panel controls offers time and resource savings. More rapid investigations would enable more prompt implementation of control measures. We recommend that this method of recruiting controls is considered in future investigations and assessed further to better understand strengths and limitations. PMID:26493476

  15. Association between Interleukin-6 Gene Polymorphisms and Rheumatoid Arthritis in Chinese Han Population: A Case-Control Study and A Meta-analysis

    PubMed Central

    Li, Feng; Xu, Jing; Zheng, Jiatian; Sokolove, Jeremy; Zhu, Kai; Zhang, Yuanchao; Sun, Hongsheng; Evangelou, Evangelos; Pan, Zhenglun

    2014-01-01

    The aim of this study was to investigate the possible association in the interleukin-6 (IL-6) gene with Rheumatoid arthritis (RA) in Chinese Han population from Shandong Province. Target regions of IL-6 gene were amplified by polymerase chain reaction (PCR) and genotyped. A logistic regression analysis was performed to detect potential associations in our case-control sample, the odd ratio(OR) and 95% confidence intervals(CIs) were calculated. Furthermore, we systematically tracked all the published studies in the field and performed a meta-analysis for the single nucleotide polymorphisms (SNPs) under study. 256 RA patients and 331 healthy controls were recruited into the case-control study. We found allele frequencies of rs1800795, rs1800797 and rs1474347 in RA patients differ from control subjects (P = 0.016, 0.024, 0.020, respectively). Significant difference was observed in haplotype frequencies of GCCGCT between RA patients and controls (P = 0.0001, OR = 4.066, 95%CI = 1.891 ~ 8.746), while GGCGCT frequencies was found lower in RA than controls (P = 0.006, OR = 0.669, 95%CI = 0.501 ~ 0.894). The results of the meta-analysis showed association polymorphism within the IL-6 promoter with RA. These findings suggest that rare IL-6 gene polymorphisms may associate with RA susceptibility in Han Chinese populations; however further studies are needed to assess the validity of the association of IL-6 with RA. PMID:25030201

  16. Multicenter assessment of burn team injury prevention knowledge.

    PubMed

    Klas, Karla S; Smith, Sue Jane; Matherly, Annette F; Dillard, B Daniel; Grant, Ernest J; Cusick-Jost, Janet

    2015-01-01

    Engaging burn professionals to utilize "teachable moments" and provide accurate fire safety and burn prevention (FSBP) education is essential in reducing injury incidence. Minimal data is available regarding burn clinicians' evidence-based FSBP knowledge. A committee of prevention professionals developed, pilot-tested, and distributed a 52-question online survey assessing six major categories: demographical information (n = 7); FSBP knowledge (n = 24); home FSBP practices (n = 6); burn center FSBP education (n = 7); self-assessed competence and confidence in providing FSBP education (n = 2); and improving ABA reach (n = 6). Responses with <50% completion of FSBP knowledge section were excluded. Total group's (TG) mean FSBP score of 61.5% was used to define and compare underperformers (UP). After excluding 36 incomplete responses, test scores ranged: TG (n = 427) 21-88% and UP (n = 183) 21-58%. Ten FSBP knowledge questions covering seven topics were incorrectly answered by >50% of TG. ANOVA showed self-reported competence and confidence in providing FSBP education were not good predictors of FSBP scores, but staff with <2 years experience scored lower. Over 90% of TG wants FSBP fact sheets for patient education. Burn professionals have a responsibility to educate patients, families, and communities on FSBP. Team members report competence and confidence in their ability to provide FSBP education. However, this multicenter survey demonstrates the need for professional training on best practices in injury prevention, specifically targeting knowledge gaps on: smoke alarms, fire-safe cigarettes, children's sleepwear, burn/fire epidemiology, fireworks, bathing/scald injuries, and residential sprinklers. Based on these findings, FSBP educational materials will be created. PMID:25094010

  17. Influenza vaccination coverage among medical residents: an Italian multicenter survey.

    PubMed

    Costantino, Claudio; Mazzucco, Walter; Azzolini, Elena; Baldini, Cesare; Bergomi, Margherita; Biafiore, Alessio Daniele; Bianco, Manuela; Borsari, Lucia; Cacciari, Paolo; Cadeddu, Chiara; Camia, Paola; Carluccio, Eugenia; Conti, Andrea; De Waure, Chiara; Di Gregori, Valentina; Fabiani, Leila; Fallico, Roberto; Filisetti, Barbara; Flacco, Maria E; Franco, Elisabetta; Furnari, Roberto; Galis, Veronica; Gallea, Maria R; Gallone, Maria F; Gallone, Serena; Gelatti, Umberto; Gilardi, Francesco; Giuliani, Anna R; Grillo, Orazio C; Lanati, Niccolò; Mascaretti, Silvia; Mattei, Antonella; Micò, Rocco; Morciano, Laura; Nante, Nicola; Napoli, Giuseppe; Nobile, Carmelo Giuseppe; Palladino, Raffaele; Parisi, Salvatore; Passaro, Maria; Pelissero, Gabriele; Quarto, Michele; Ricciardi, Walter; Romano, Gabriele; Rustico, Ennio; Saponari, Anita; Schioppa, Francesco S; Signorelli, Carlo; Siliquini, Roberta; Trabacchi, Valeria; Triassi, Maria; Varetta, Alessia; Ziglio, Andrea; Zoccali, Angela; Vitale, Francesco; Amodio, Emanuele

    2014-01-01

    Although influenza vaccination is recognized to be safe and effective, recent studies have confirmed that immunization coverage among health care workers remain generally low, especially among medical residents (MRs). Aim of the present multicenter study was to investigate attitudes and determinants associated with acceptance of influenza vaccination among Italian MRs. A survey was performed in 2012 on MRs attending post-graduate schools of 18 Italian Universities. Each participant was interviewed via an anonymous, self-administered, web-based questionnaire including questions on attitudes regarding influenza vaccination. A total of 2506 MRs were recruited in the survey and 299 (11.9%) of these stated they had accepted influenza vaccination in 2011-2012 season. Vaccinated MRs were older (P = 0.006), working in clinical settings (P = 0.048), and vaccinated in the 2 previous seasons (P<0.001 in both seasons). Moreover, MRs who had recommended influenza vaccination to their patients were significantly more compliant with influenza vaccination uptake in 2011-2012 season (P<0.001). "To avoid spreading influenza among patients" was recognized as the main reason for accepting vaccination by less than 15% of vaccinated MRs. Italian MRs seem to have a very low compliance with influenza vaccination and they seem to accept influenza vaccination as a habit that is unrelated to professional and ethical responsibility. Otherwise, residents who refuse vaccination in the previous seasons usually maintain their behaviors. Promoting correct attitudes and good practice in order to improve the influenza immunization rates of MRs could represent a decisive goal for increasing immunization coverage among health care workers of the future.

  18. Neurophysiology versus clinical genetics in Rett syndrome: A multicenter study.

    PubMed

    Halbach, Nicky; Smeets, Eric E; Julu, Peter; Witt-Engerström, Ingegerd; Pini, Giorgio; Bigoni, Stefania; Hansen, Stig; Apartopoulos, Flora; Delamont, Robert; van Roozendaal, Kees; Scusa, Maria F; Borelli, Paolo; Candel, Math; Curfs, Leopold

    2016-09-01

    Many studies have attempted to establish the genotype-phenotype correlation in Rett syndrome (RTT). Cardiorespiratory measurements provide robust objective data, to correlate with each of the different clinical phenotypes. It has important implications for the management and treatment of this syndrome. The aim of this study was to correlate the genotype with the quantitative cardiorespiratory data obtained by neurophysiological measurement combined with a clinical severity score. This international multicenter study was conducted in four European countries from 1999 to 2012. The study cohort consisted of a group of 132 well-defined RTT females aged between 2 and 43 years with extended clinical, molecular, and neurophysiological assessments. Diagnosis of RTT was based on the consensus criteria for RTT and molecular confirmation. Genotype-phenotype analyses of clinical features and cardiorespiratory data were performed after grouping mutations by the same type and localization or having the same putative biological effect on the MeCP2 protein, and subsequently on eight single recurrent mutations. A less severe phenotype was seen in females with CTS, p.R133C, and p.R294X mutations. Autonomic disturbances were present in all females, and not restricted to nor influenced by one specific group or any single recurrent mutation. The objective information from non-invasive neurophysiological evaluation of the disturbed central autonomic control is of great importance in helping to organize the lifelong care for females with RTT. Further research is needed to provide insights into the pathogenesis of autonomic dysfunction, and to develop evidence-based management in RTT. © 2016 Wiley Periodicals, Inc.

  19. Analytically reduced form of multicenter integrals from Gaussian transforms. [in atomic and molecular physics

    NASA Technical Reports Server (NTRS)

    Straton, Jack C.

    1989-01-01

    The four-dimensional Fourier-Feynman transformations previously used in analytically reducing the general class of integrals containing multicenter products of 1s hydrogenic orbitals, Coulomb or Yukawa potentials, and plane waves, are replaced by the one-dimensional Gaussian transformation. This reduces the previously required double-diagonalization of the quadratic form of the multicenter integrals to only one diagonalization, yielding a simpler reduced form of the integral. The present work also extends the result to include all s states and pairs of states with l not equal to zero summed over the m quantum number.

  20. Potential role of real-time PCR for detecting Mycobacterium avium subsp. paratuberculosis in chronically diseased milking cows: a case control study.

    PubMed

    Alajmi, Ahmad; Klein, Günter; Greiner, Matthias; Grabowski, Nils Th; Fohler, Svenja; Campe, Amely; Scheu, Theresa; Hoedemaker, Martina; Abdulmawjood, Amir

    2016-01-01

    Paratuberculosis caused by Mycobacterium avium subsp. paratuberculosis (MAP) is economically important to dairy operations. In the present study, a real-time PCR kit (certified for use in Germany) was used to detect MAP in bovine fecal and milk samples within a case control study examining different factors for their association with chronic disease in Northern Germany.The aim of this study was to describe the suitability of the MAP real-time PCR kit to detect MAP in feces and milk of chronically diseased dairy cows. For MAP detection a total of 928 fecal, 922 composite foremilk, and 92 bulk milk samples obtained from 58 cases and 35 control dairy herds were investigated. The real-time PCR showed MAP positive results for 11 (18.96%) and 6 (17.14%) of the case and control herds, respectively. All bulk milk samples were MAP negative. The results of fecal and milk samples were moderately correlated (kappa = 0.27). These data indicate that real-time PCR results have diagnostic value for diagnosing MAP positive animals, and that fecal samples are more suitable than milk samples for assessing the reasons for chronic disease on dairy farms. PMID:27529992

  1. Impact of Urate Level on Cardiovascular Risk in Allopurinol Treated Patients. A Nested Case-Control Study

    PubMed Central

    Søltoft Larsen, Kasper; Pottegård, Anton; Lindegaard, Hanne M.; Hallas, Jesper

    2016-01-01

    Background Gout gives rise to increased risk of cardiovascular events. Gout attacks can be effectively prevented with urate lowering drugs, and allopurinol potentially reduces cardiovascular risk. What target level of urate is required to reduce cardiovascular risk is not known. Objectives To investigate the effect of achieving target plasma urate with allopurinol on cardiovascular outcomes in a case-control study nested within long-term users of allopurinol. Methods We identified long-term users of allopurinol in Funen County, Denmark. Among these, we identified all cases of cardiovascular events and sampled 4 controls to each case from the same population. The cases and controls were compared with respect to whether they reached a urate target below 0.36 mmol/l on allopurinol. The derived odds ratios were controlled for potential confounders available from data on prescriptions, laboratory values and in- and outpatient contacts. Results No association between treatment-to-target urate level and cardiovascular events were found (adjusted odds ratio of 1.01, 95% confidence interval 0.79–1.28). No significant effect was seen in any subgroup defined by age, gender, renal function, allopurinol dose or the achieved urate level. Overall, the doses of allopurinol used in this study were low (mean ≈ 140 mg/day). Conclusion We were unable to demonstrate a link between achieved urate level in patients treated with allopurinol and risk of cardiovascular events. Possible explanations include that allopurinol doses higher than those used in this study are required to achieve cardiovascular risk reduction or that the cardiovascular effect of allopurinol is not mediated through low urate levels. It remains to be seen whether allopurinol has a dose-response relationship with cardiovascular events at higher doses. PMID:26751377

  2. Determinants of Desire for Children among HIV-Positive Women in the Afar Region, Ethiopia: Case Control Study

    PubMed Central

    2016-01-01

    Introduction The desire for a child in Ethiopian society is normal. Among HIV positive women, due to the risk of MTCT, it is imperative to understand factors influencing women’s desire for children. This study aimed at assessing factors associated with desire for children among HIV-positive women in two selected hospitals of Afar Regional State, Ethiopia. Methods A facility based case-control study was conducted among 157 cases (with a desire) and 157 controls of HIV positive individuals registered in the selected health facilities. The participants were selected by random sampling technique. Data were collected using face-to-face interview and was analyzed using logistic regression. Result Factors found to be independently associated with desire for children were age categories of 20–24 years (OR = 6.22, 1.29–10.87) and 25–29 years (OR = 14.6, 3.05–21.60), being married (OR = 5.51, 2.19–13.54), Afar ethnicity (OR 6.93, 1.19–12.14), having HIV-positive children (OR 0.23, 0.09–0.63), duration on ART more than one year (3.51, 1.68–9.05), CD4 count greater than 350 (OR 4.83, 1.51–7.27) and discussion of reproductive health issues with health providers (OR 0.31, 0.12–0.51). Conclusion Women who were young, married, Afar, those who received ART more than one year, and had CD4 count >350 were more likely to have a desire for children. Recommendation Health care workers at ART clinic should openly discuss about the reproductive options for the women living with HIV/AIDS. PMID:26930467

  3. Risk factors for MRSA infection in companion animals: results from a case-control study within Germany.

    PubMed

    Vincze, Szilvia; Brandenburg, Anja G; Espelage, Werner; Stamm, Ivonne; Wieler, Lothar H; Kopp, Peter A; Lübke-Becker, Antina; Walther, Birgit

    2014-10-01

    Increasing numbers of companion animals suffering from infections with methicillin-resistant Staphylococcus aureus (MRSA) have been reported in the recent past. These infections are of particular concern because of the limited treatment options for MRSA and their transferability to humans. Since MRSA lineages isolated from infected companion animals often mirror typical human epidemic strains circulating in the same region, successful strategies to combat MRSA need strong and coordinated efforts from both, the human and the veterinary field according to the "One Health" concept. Hence, to identify potential risk factors related to MRSA infections in dogs, cats and horses, a case-control study was conducted, including data on 106 MRSA-infected animal patients as cases and 102 MSSA-infected animals as controls, originating from 155 different veterinary settings within Germany. Demographic data on animal patients, patient history and administration of antibiotics as well as practice/clinic specific parameters were assessed as putative risk factors. Multivariable logistic regression identified the following variables as risk factors for MRSA infection compared to MSSA infection: number of employees working at the veterinary setting (n>10; p<0.001), antibiotic treatment prior to sampling (systemic: p=0.002; local: p=0.049, both: p=0.011) and surgical site infection (p<0.001). Spa typing revealed predominantly clonal complexes well-known for hospital-associated lineages spreading in human health-care settings in Germany (CC5 and CC22) for isolates of dog and cat origin. CC398-MRSA dominated among equine isolates, a CC that was described as a nosocomial pathogen in equine clinical settings before. The identified risk factors and genotyping results are in accordance with numerous study outcomes from the field of human medicine and point towards reasonable problems with nosocomial spread of MRSA, especially within companion animal veterinary clinics. To define targeted

  4. The association between dental and periodontal diseases and sickle cell disease. A pilot case-control study

    PubMed Central

    Al-Alawi, Haidar; Al-Jawad, Abdulfatah; Al-Shayeb, Mahdi; Al-Ali, Ali; Al-Khalifa, Khalifa

    2014-01-01

    Objective This is a pilot case-control study conducted to investigate the prevalence of dental caries and periodontal disease and examine the possible association between oral health deterioration and SCD severity in a sample of Saudi SCD patients residing in the city of Al-Qatif, Eastern Province, Saudi Arabia. Materials and methods Dental examination to determine the Decayed, Missing and Filled Teeth index (DMFT), Community Periodontal Index (CPI), and plaque index system were recorded for 33 SCD patients and 33 age and sex-matched controls in the Al-Qatif Central Hospital, Qatif, Saudi Arabia. Self-administered surveys used to assess socio-economic status; oral health behaviors for both SCD patients and controls were recorded. In addition, the disease severity index was established for all patients with SCD. SPSS data analysis software package version 18.0 was used for statistical analysis. Numerical variables were described as mean with a standard deviation. Results Decayed teeth were significantly more in individuals with ages ranging from 18 to 38 years with SCD compared to the control group (p = 0.036) due to oral hygiene negligence. The mean number of filled teeth was significantly lower in individuals with SCD when compared to the control group (p = 0.015) due to the lack of appropriate and timely treatment reflected in the survey responses of SCD patients as 15.2% only taking oral care during hospitalization. There were differences between the cases and controls in the known caries risk factors such as income level, flossing, and brushing habit. The DMFT, CPI, and plaque index systems did not differ significantly between the SCD patients and the control group. Conclusion Data suggest that patients with SCD have increased susceptibility to dental caries, with a higher prevalence of tooth decay and lower prevalence of filled teeth. Known caries risk factors influenced oral health more markedly than did factors related to SCD. PMID:25544813

  5. Personality profiles and risk diet behaviors--a case-control study on teenagers from Timis County, Romania.

    PubMed

    Petrescu, Cristina; Vlaicu, Brigitha

    2014-01-01

    In the study we conducted we aimed at investigating the relation between personality profiles and risk diet behaviors in teenagers. This study was a case-control one and we applied 2 questionnaires (Freiburg Personality Inventory--FPI with 212 items) and CORT 2004 (items Q94-Q116 of diet behavior) on a sample of 2908 teenagers (51.5% girls and 48.5% boys). Cronbach's alpha index was 0.802 for FPI and 0.730 for items Q101-Q109 of CORT. Personality profiles were built by an Excel 2003 Program. Statistical analysis was realized with SPSS 16 program applying Chi square (chi2) and gamma (gamma) correlation. Personality features of teenagers with high and without risk diet behavior were analyzed. Results obtained: personality profiles and statistical results indicated the existence of a significant statistical difference of aggressiveness and domination between teenagers with high and no consumption of butter and/or lard (Q103) (chi2 = 6.872, Sig. 0.032 and chi2 = 6.922, Sig. 0.031 respectively), of juices from the market (Q106) (chi2 = 9.055, Sig. 0.011 and chi2 = 14.571, Sig. 0.001 respectively). Aggressiveness correlated with consumption of fried potatoes (Q109) (chi2 = 6.144, Sig. 0.046) too. Correlation gamma indicated direct proportional relations of aggressiveness with: Q103 (gamma = 0.215, Sig. 0.017), Q106 (gamma = 0.224, Sig. 0.004), Q109 (gamma = 0.242, Sig. 0.012); and of domination with: Q103 (gamma = 0.234, Sig. 0.008), Q106 (gamma = 0.073, Sig. 0.000). In conclusion, there is a direct proportional relation between consumption of: butter/lard, juices from the market and teenagers' aggressiveness, domination; and a similar relation between consumption of fried potatoes and aggressiveness.

  6. Intestinal Protozoal Parasites in Diarrheal Children and Associated Risk Factors at Yirgalem Hospital, Ethiopia: A Case-Control Study

    PubMed Central

    Abunna, Fufa; Girma, Mekonnen

    2014-01-01

    Aim. A case-control study was conducted to determine the prevalence of G. lamblia, Cryptosporidium, spp and E. histolytica/dispar in diarrheal children at Yirgalem Hospital from February 2011 to August. Subjects and Methods. A total of 230 children participated in the study of which 115 (50%) were cases and 115 (50%) were controls. A single stool sample was collected and examined by direct saline wet mount, formol-ether concentration, and modified Ziehl-Neelsen. Results. Eighty-four (36.52%) were positive for at least one intestinal parasites (57 (49.56%) from diarrheal children and 27 (23.47%) out of nondiarrheal children). The prevalence of G. lamblia, Cryptosporidium spp, and E. histolytica/dispar was 15.65%, 9.56%, and 4.35% in children with diarrhea and 1.74%, 5.21%, and 1.74% in those without it, respectively. Cryptosporidium spp and E. histolytica/dispar revealed higher infection in males (10.81% and 5.4%, resp.) than in females (7.32% and 2.43%, resp.). G. lamblia infection was higher in females (29.27%) than in males (8.11%). Cryptosporidium spp infection was higher in the age groups of ≤4 years old (53.84%). Significant difference was seen between 10 and 13 (7.69%) years old. Higher prevalence of E. histolytica/dispar was found in 5–9 years (85.71%) than ≤4 years old (14.28%). Conclusion. Cryptosporidium spp, E. histolytica/dispar, and G. lamblia were higher in children with diarrhea than in those without it. PMID:27355052

  7. Bus Stops and Pedestrian-Motor Vehicle Collisions in Lima, Peru: A Matched Case-Control Study

    PubMed Central

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

    2015-01-01

    Objective To evaluate the relationship between bus stop characteristics and pedestrian-motor vehicle collisions. Design Matched case-control study where the units of study were pedestrian crossing. Setting Random sample of 11 police commissaries in Lima, Peru. Data collection occurred from February, 2011 to September, 2011. Participants 97 intersection cases representing 1,134 collisions and 40 mid-block cases representing 469 collisions that occurred between October, 2010 and January, 2011 and their matched controls. Main Exposures Presence of a bus stop and specific bus stop characteristics. Main Outcome Occurrence of a pedestrian-motor vehicle collision. Results Intersections with bus stops were three times more likely to have a pedestrian-vehicle collision (OR 3.28, 95% CI 1.53-7.03), relative to intersections without bus stops. Both formal and informal bus stops were associated with a higher odds of a collision at intersections (OR 6.23, 95% CI 1.76-22.0 and OR 2.98, 1.37-6.49). At mid-block sites, bus stops on a bus-dedicated transit lane were also associated with collision risk (OR 2.36, 95% CI 1.02-5.42). All bus stops were located prior to the intersection, contrary to practices in most high income countries. Conclusions In urban Lima, the presence of a bus stop was associated with a three-fold increase in risk of a pedestrian collision. The highly competitive environment among bus companies may provide an economic incentive for risky practices such as dropping off passengers in the middle of traffic and jockeying for position with other buses. Bus stop placement should be considered to improve pedestrian safety. PMID:24357516

  8. Blood Reference Intervals for Preterm Low-Birth-Weight Infants: A Multicenter Cohort Study in Japan

    PubMed Central

    Inoue, Hirosuke; Kusuda, Takeshi; Kang, Dongchon; Ichihara, Kiyoshi; Nakashima, Naoki; Ihara, Kenji; Ohga, Shouichi; Hara, Toshiro

    2016-01-01

    Preterm low-birth-weight infants remain difficult to manage based on adequate laboratory tests. The aim of this study was to establish blood reference intervals (RIs) in those newborns who were admitted to and survived in the neonatal intensive care unit (NICU). A multicenter prospective study was conducted among all infants admitted to 11 affiliated NICUs from 2010 to 2013. The clinical information and laboratory data were registered in a network database designed for this study. The RIs for 26 items were derived using the parametric method after applying the latent abnormal values exclusion method. The influence of birth weight (BW) and gestational age (GA) on the test results was expressed in terms of the standard deviation ratio (SDR), as SDRBW and SDRGA, respectively. A total of 3189 infants were admitted during the study period; 246 were excluded due to a lack of blood sampling data, and 234 were excluded for chromosomal abnormalities (n = 108), congenital anomalies requiring treatment with surgical procedures (n = 76), and death or transfer to another hospital (n = 50). As a result, 2709 infants were enrolled in this study. Both the SDRGA and SDRBW were above 0.4 in the test results for total protein (TP), albumin (ALB), alanine aminotransferase (ALT), and red blood cells (RBC); their values increased in proportion to the BW and GA. We derived 26 blood RIs for infants who were admitted to NICUs. These RIs should help in the performance of proper clinical assessments and research in the field of perinatal-neonatal medicine. PMID:27552225

  9. Family Presence during Resuscitation: A Qualitative Analysis from a National Multicenter Randomized Clinical Trial

    PubMed Central

    De Stefano, Carla; Normand, Domitille; Jabre, Patricia; Azoulay, Elie; Kentish-Barnes, Nancy; Lapostolle, Frederic; Baubet, Thierry; Reuter, Paul-Georges; Javaud, Nicolas; Borron, Stephen W.; Vicaut, Eric; Adnet, Frederic

    2016-01-01

    Background The themes of qualitative assessments that characterize the experience of family members offered the choice of observing cardiopulmonary resuscitation (CPR) of a loved one have not been formally identified. Methods and Findings In the context of a multicenter randomized clinical trial offering family members the choice of observing CPR of a patient with sudden cardiac arrest, a qualitative analysis, with a sequential explanatory design, was conducted. The aim of the study was to understand family members’ experience during CPR. All participants were interviewed by phone at home three months after cardiac arrest. Saturation was reached after analysis of 30 interviews of a randomly selected sample of 75 family members included in the trial. Four themes were identified: 1- choosing to be actively involved in the resuscitation; 2- communication between the relative and the emergency care team; 3- perception of the reality of the death, promoting acceptance of the loss; 4- experience and reactions of the relatives who did or did not witness the CPR, describing their feelings. Twelve sub-themes further defining these four themes were identified. Transferability of our findings should take into account the country-specific medical system. Conclusions Family presence can help to ameliorate the pain of the death, through the feeling of having helped to support the patient during the passage from life to death and of having participated in this important moment. Our results showed the central role of communication between the family and the emergency care team in facilitating the acceptance of the reality of death. PMID:27253993

  10. Medical students, spirituality and religiosity-results from the multicenter study SBRAME

    PubMed Central

    2013-01-01

    Background To evaluate the relationship between spirituality/religiosity (S/R) and the attitudes, beliefs and experiences of medical students in Brazil with respect to S/R in their undergraduate training and clinical practice. Methods SBRAME (Spirituality and Brazilian Medical Education) is a multicenter study involving 12 Brazilian medical schools with 5950 medical students (MS). Participants completed a questionnaire that collected information on socio-demographic data and S/R in their undergraduate training and practice. Results Of all MS, 3630 participated in the survey (61.0%). The sample was 53.8% women and the mean age was 22.5 years. The majority of MS believed that spirituality has an impact on patients’ health (71.2%) and that this impact was positive (68.2%). The majority also wanted to address S/R in their clinical practice (58.0%) and considered it relevant (75.3%), although nearly one-half (48.7%) felt unprepared to do so. Concerning their training, most MS reported that they had never participated in a “spirituality and health” activity (81.0%) and that their medical instructors had never or rarely addressed this issue (78.3%). The majority also believed that they should be prepared to address spiritual issues related to the health of their patients (61.6%) and that this content should be included in the medical curriculum (62.6%). Conclusion There is a large gap between MS attitudes and expectations and the S/R training that they are receiving during their undergraduate training. The majority of MS surveyed believe that patients should have their beliefs addressed and that these beliefs could have important effects on their health and the doctor-patient relationship. These results should stimulate discussion about the place that S/R training should have in the medical curriculum. PMID:24314327

  11. Nationwide Multicenter Reference Interval Study for 28 Common Biochemical Analytes in China

    PubMed Central

    Xia, Liangyu; Chen, Ming; Liu, Min; Tao, Zhihua; Li, Shijun; Wang, Liang; Cheng, Xinqi; Qin, Xuzhen; Han, Jianhua; Li, Pengchang; Hou, Li’an; Yu, Songlin; Ichihara, Kiyoshi; Qiu, Ling

    2016-01-01

    Abstract A nationwide multicenter study was conducted in the China to explore sources of variation of reference values and establish reference intervals for 28 common biochemical analytes, as a part of the International Federation of Clinical Chemistry and Laboratory Medicine, Committee on Reference Intervals and Decision Limits (IFCC/C-RIDL) global study on reference values. A total of 3148 apparently healthy volunteers were recruited in 6 cities covering a wide area in China. Blood samples were tested in 2 central laboratories using Beckman Coulter AU5800 chemistry analyzers. Certified reference materials and value-assigned serum panel were used for standardization of test results. Multiple regression analysis was performed to explore sources of variation. Need for partition of reference intervals was evaluated based on 3-level nested ANOVA. After secondary exclusion using the latent abnormal values exclusion method, reference intervals were derived by a parametric method using the modified Box–Cox formula. Test results of 20 analytes were made traceable to reference measurement procedures. By the ANOVA, significant sex-related and age-related differences were observed in 12 and 12 analytes, respectively. A small regional difference was observed in the results for albumin, glucose, and sodium. Multiple regression analysis revealed BMI-related changes in results of 9 analytes for man and 6 for woman. Reference intervals of 28 analytes were computed with 17 analytes partitioned by sex and/or age. In conclusion, reference intervals of 28 common chemistry analytes applicable to Chinese Han population were established by use of the latest methodology. Reference intervals of 20 analytes traceable to reference measurement procedures can be used as common reference intervals, whereas others can be used as the assay system-specific reference intervals in China. PMID:26945390

  12. Blood Reference Intervals for Preterm Low-Birth-Weight Infants: A Multicenter Cohort Study in Japan.

    PubMed

    Ochiai, Masayuki; Matsushita, Yuki; Inoue, Hirosuke; Kusuda, Takeshi; Kang, Dongchon; Ichihara, Kiyoshi; Nakashima, Naoki; Ihara, Kenji; Ohga, Shouichi; Hara, Toshiro

    2016-01-01

    Preterm low-birth-weight infants remain difficult to manage based on adequate laboratory tests. The aim of this study was to establish blood reference intervals (RIs) in those newborns who were admitted to and survived in the neonatal intensive care unit (NICU). A multicenter prospective study was conducted among all infants admitted to 11 affiliated NICUs from 2010 to 2013. The clinical information and laboratory data were registered in a network database designed for this study. The RIs for 26 items were derived using the parametric method after applying the latent abnormal values exclusion method. The influence of birth weight (BW) and gestational age (GA) on the test results was expressed in terms of the standard deviation ratio (SDR), as SDRBW and SDRGA, respectively. A total of 3189 infants were admitted during the study period; 246 were excluded due to a lack of blood sampling data, and 234 were excluded for chromosomal abnormalities (n = 108), congenital anomalies requiring treatment with surgical procedures (n = 76), and death or transfer to another hospital (n = 50). As a result, 2709 infants were enrolled in this study. Both the SDRGA and SDRBW were above 0.4 in the test results for total protein (TP), albumin (ALB), alanine aminotransferase (ALT), and red blood cells (RBC); their values increased in proportion to the BW and GA. We derived 26 blood RIs for infants who were admitted to NICUs. These RIs should help in the performance of proper clinical assessments and research in the field of perinatal-neonatal medicine. PMID:27552225

  13. A multicenter evaluation of a new antibody test kit for lymphatic filariasis employing recombinant Brugia malayi antigen Bm-14

    PubMed Central

    Weil, Gary J.; Curtis, Kurt C.; Fischer, Peter U.; Won, Kimberly Y.; Lammie, Patrick J.; Joseph, Hayley; Melrose, Wayne D.; Brattig., Norbert W.

    2010-01-01

    Antibody tests are useful for mapping the distribution of lymphatic filariasis (LF) in countries and regions and for monitoring progress in elimination programs based on mass drug administration (MDA). Prior antibody tests have suffered from poor sensitivity and/or specificity or from a lack of standardization. We conducted a multicenter evaluation of a new commercial ELISA that detects IgG4 antibodies to the recombinant filarial antigen Bm14. Four laboratories tested a shared panel of coded serum or plasma samples that included 55 samples from people with microfilaremic Wuchereria bancrofti or Brugia infections and 26 control samples. Qualitative results were identical in all four test sites. In addition, each laboratory tested samples from their own serum banks. The test detected antibodies in 32 of 36 samples (91%) from people with Brugian filariasis and in 96 of 98 samples (98%) from people with Bancroftian filariasis. Specificity testing showed that many serum or plasma samples from patients with other filarial infections such as onchocerciasis had positive antibody tests. Specificity was otherwise excellent, although 3 of 30 samples from patients with ascariasis and 4 of 51 with strongyloidiasis had positive antibody tests; it is likely that some or all of these people had previously lived in filariasis-endemic areas. Antibody test results obtained with eluates from blood dried on filter paper were similar to those obtained with plasma tested at the same dilution. This test may be helpful for diagnosing LF in patients with clinical signs of filariasis. It may also be a useful tool for use in LF endemic countries to monitor the progress of filariasis elimination programs and for post-MDA surveillance. PMID:20430004

  14. A multicenter evaluation of a new antibody test kit for lymphatic filariasis employing recombinant Brugia malayi antigen Bm-14.

    PubMed

    Weil, Gary J; Curtis, Kurt C; Fischer, Peter U; Won, Kimberly Y; Lammie, Patrick J; Joseph, Hayley; Melrose, Wayne D; Brattig, Norbert W

    2011-09-01

    Antibody tests are useful for mapping the distribution of lymphatic filariasis (LF) in countries and regions and for monitoring progress in elimination programs based on mass drug administration (MDA). Prior antibody tests have suffered from poor sensitivity and/or specificity or from a lack of standardization. We conducted a multicenter evaluation of a new commercial ELISA that detects IgG4 antibodies to the recombinant filarial antigen Bm14. Four laboratories tested a shared panel of coded serum or plasma samples that included 55 samples from people with microfilaremic Wuchereria bancrofti or Brugia infections and 26 control samples. Qualitative results were identical in all four test sites. In addition, each laboratory tested samples from their own serum banks. The test detected antibodies in 32 of 36 samples (91%) from people with Brugian filariasis and in 96 of 98 samples (98%) from people with Bancroftian filariasis. Specificity testing showed that many serum or plasma samples from patients with other filarial infections such as onchocerciasis had positive antibody tests. Specificity was otherwise excellent, although 3 of 30 samples from patients with ascariasis and 4 of 51 with strongyloidiasis had positive antibody tests; it is likely that some or all of these people had previously lived in filariasis-endemic areas. Antibody test results obtained with eluates from blood dried on filter paper were similar to those obtained with plasma tested at the same dilution. This test may be helpful for diagnosing LF in patients with clinical signs of filariasis. It may also be a useful tool for use in LF endemic countries to monitor the progress of filariasis elimination programs and for post-MDA surveillance.

  15. Analgesics use and ESRD in younger age: a case-control study

    PubMed Central

    van der Woude, Fokke J; Heinemann, Lothar AJ; Graf, Helmut; Lewis, Michael; Moehner, Sabine; Assmann, Anita; Kühl-Habich, Doerthe

    2007-01-01

    Background An ad hoc peer-review committee was jointly appointed by Drug Authorities and Industry in Germany, Austria and Switzerland in 1999/2000 to review the evidence for a causal relation between phenacetin-free analgesics and nephropathy. The committee found the evidence as inconclusive and requested a new case-control study of adequate design. Methods We performed a population-based case-control study with incident cases of end-stage renal disease (ESRD) under the age of 50 years and four age and sex-matched neighborhood controls in 170 dialysis centers (153 in Germany, and 17 in Austria) from January 1, 2001 to December 31, 2004. Data on lifetime medical history, risk factors, treatment, job exposure and intake of analgesics were obtained in a standardized face-to-face interview using memory aids to enhance accuracy. Study design, study performance, analysis plan, and study report were approved by an independent international advisory committee and by the Drug Authorities involved. Unconditional logistic regression analyses were performed. Results The analysis included 907 cases and 3,622 controls who had never used phenacetin-containing analgesics in their lifetime. The use of high cumulative lifetime dose (3rd tertile) of analgesics in the period up to five years before dialysis was not associated with later ESRD. Adjusted odds ratios with 95% confidence intervals were 0.8 (0.7 – 1.0) and 1.0 (0.8 – 1.3) for ever- compared with no or low use and high use compared with low use, respectively. The same results were found for all analgesics and for mono-, and combination preparations with and without caffeine. No increased risk was shown in analyses stratifying for dose and duration. Dose-response analyses showed that analgesic use was not associated with an increased risk for ESRD up to 3.5 kg cumulative lifetime dose (98 % of the cases with ESRD). While the large subgroup of users with a lifetime dose up to 0.5 kg (278 cases and 1365 controls) showed a

  16. A Metagenomics and Case-Control Study To Identify Viruses Associated with Bovine Respiratory Disease

    PubMed Central

    Kondov, Nikola O.; Deng, Xutao; Van Eenennaam, Alison; Neibergs, Holly L.

    2015-01-01

    approach, we characterized the viruses in respiratory secretions from BRD cases and identified known and previously uncharacterized viruses belonging to seven viral families. Using a case-control format with location-matched animals, we compared the rates of viral detection and identified 3 viruses associated with severe BRD signs. Combining a metagenomics and case-control format can provide candidate pathogens associated with complex infectious diseases and inform further studies aimed at reducing their impact. PMID:25740998

  17. Symptoms and sources of Yersinia enterocolitica-infection: a case-control study

    PubMed Central

    2010-01-01

    Background Yersinia enterocolitica (YE) is the causative agent of yersiniosis. YE encompass strains of diverse pathogenicity: YE biotypes 1B and 2-5 are considered pathogenic, whereas biotype 1A is in general considered nonvirulent. Also YE-like species, which can sometimes be misidentified as YE, are considered nonvirulent. Methods In order to study differences in clinical picture caused by different YE types and their possible sources a case-control study was conducted in 2006. In this case-control study, 295 case-patients with YE or YE-like finding and their 758 controls responded to the questionnaire about symptoms and possible sources of infection. Results Strains of pathogenic YE bio/serotypes 3-4/O:3 or 2/O:9 were found in 18%, YE biotype 1A in 65% and YE -like strains of 17% of the patients. Patients infected with the strains of pathogenic YE bio/serotypes were younger and had fever more often than those with BT 1A who suffered more from vomiting. Symptoms of reactive arthritis were reported by 10% of pathogenic YE infections, 3% of YE BT 1A, and 0.3% of the controls. Eating or tasting raw or medium done pork was a significant risk factor for pathogenic YE bio/serotype infection (OR 6.6; 95% CI 1.7-24.9) as well as eating in a canteen (OR 3.5; 95% CI 1.6-7.9). Imported fruits and berries were associated with increased risk of YE BT 1A finding. Conclusions The symptoms of the patients with YE BT 1A differed from yersiniosis caused by the classic pathogenic YE bio/serotypes. In addition, the patients with YE BT 1A had more protracted gastrointestinal disorders and unspecific complaints. Small children were overrepresented in classic pathogenic bio/serotypes while in BT 1A or YE-like species were not found among children younger than two years. This suggests the lacking virulence of the BT 1A strains. We can not, however, rule out the possibility that some strains of genetically heterogeneous group of BT 1A may cause an illness. PMID:20487529

  18. Case-control study of sudden infant death syndrome in Lithuania, 1997–2000

    PubMed Central

    Bubnaitienė, Vilija; Kalėdienė, Ramunė; Kėvalas, Rimantas

    2005-01-01

    Background To identify risk factors for sudden infant death syndrome relevant in Lithuania. Methods A nationwide case-control study surveying parents of 35 infants who died from sudden infant death syndrome during the period of 1997–2000 and parents of 145 control infants matched with SIDS infants for date of birth and for region of birth was carried out. Results Deaths incidence was greater in the warm period (60%) vs. cold period (40%). Prone and side sleeping positions both carried no increased risk of sudden infant death syndrome compared with supine because of a rare prone sleeping (4.1% of controls vs. 0% of dead infants) and more prevalent side than supine sleeping (84.8% of controls vs. 94.3% of dead infants) in the controls as well as the cases. Bed sharing for the whole night as a risk factor for sudden infant death syndrome has not been confirmed, either, as bed sharing was common only for the controls (13.8% of controls vs. 0% of dead infants). Routine sleeping environment factors such as heavy wrapping (≥4 togs) of an infant (odds ratio 8.49; 95% confidence interval 2.38 to 30.32), sleeping in a bassinet (4.22; 1.16 to 15.38) and maternal factors such as maternal education ≤12 years (4.48; 1.34 to 14.94), unplanned pregnancy (5.22; 1.49 to 18.18) and ≥2 previous live births (3.90; 1.00 to 15.10) were significantly associated with sudden infant death syndrome on multivariate analysis. Conclusion The results of this first population-based case-control study have shed some light on the epidemiology of the syndrome in Lithuania. Although the mortality of sudden infant death syndrome in Lithuania is not high, it might be lowered moreover by public informing about sudden infant death syndrome and related risk factors. Special attention must be paid to mothers with low education on potentially modifiable risk factors such as routine heavy wrapping of an infant during sleep, routine sleeping in a bassinet and unplanned pregnancy. PMID:16283946

  19. Housing and tuberculosis in an Inuit village in northern Quebec: a case-control study

    PubMed Central

    Khan, Faiz Ahmad; Fox, Greg J.; Lee, Robyn S.; Riva, Mylene; Benedetti, Andrea; Proulx, Jean-François; Jung, Shelley; Hornby, Karen; Behr, Marcel A.; Menzies, Dick

    2016-01-01

    Background: Between November 2011 and November 2012, an Inuit village in Nunavik, Quebec experienced a surge in the occurrence of active TB; contact investigations showed that TB infection was highly prevalent (62.6%), particularly among those over age 14 years (78.8%). A nested case-control study showed that nutritional inadequacy was associated with acquisition of infection but not progression to disease. We performed a study to determine whether characteristics of one's dwelling were associated with 1) acquisition of newly diagnosed TB infection and 2) progression to confirmed or probable disease among those with TB infection. Methods: In this nested case-control study, we enrolled 200 people who were household or social contacts of at least 1 person with active TB or had received a diagnosis of active TB and assessed whether characteristics of their dwellings were associated with their odds of having newly diagnosed TB infection and/or odds of progression to disease between November 2011 and November 2012. For our first objective, we compared participants with newly diagnosed TB infection (regardless of their disease status) to a control group of contacts who were uninfected. For the second objective, we compared participants with confirmed or probable disease to a control group consisting of those with infection but no disease. We used information collected during investigation of the contacts and from study questionnaires to determine whether participants may have been exposed to TB in their own home (if they had shared a dwelling with someone who had smear-positive TB during the outbreak) or in other dwellings that they visited at least weekly. Results: The participants lived in 79 dwellings. The mean number of people per room was 1.1 (standard deviation [SD] 0.5). The mean room size and ventilation level of the common living space (kitchen and living/dining rooms) were 67.9 (SD 9.4) m3 and 1.69 (SD 0.26) air changes per hour, respectively. After adjustment

  20. An overview of the North American residential radon and lung cancer case-control studies.

    PubMed

    Field, R William; Krewski, Daniel; Lubin, Jay H; Zielinski, Jan M; Alavanja, Michael; Catalan, Vanessa S; Klotz, Judith B; Létourneau, Ernest G; Lynch, Charles F; Lyon, Joseph L; Sandler, Dale P; Schoenberg, Janet B; Steck, Daniel J; Stolwijk, Jan A; Weinberg, Clarice; Wilcox, Homer B

    2006-04-01

    Lung cancer has held the distinction as the most common cancer type worldwide since 1985 (Parkin et al., 1993). Recent estimates suggest that lung cancer accounted for 1.2 million deaths worldwide in 2002, which represents 17.6% of the global cancer deaths (Parkin et al., 2005). During 2002, the highest lung cancer rates for men worldwide reportedly occurred in North America and Eastern Europe, whereas the highest rates in females occurred in North America and Northern Europe (Parkin et al., 2005). While tobacco smoking is the leading risk factor for lung cancer, because of the magnitude of lung cancer mortality, even secondary causes of lung cancer present a major public health concern (Field, 2001). Extrapolations from epidemiologic studies of radon-exposed miners project that approximately 18,600 lung cancer deaths per year (range 3000 to 41,000) in the United States alone are attributable to residential radon progeny exposure (National Research Council, 1999). Because of differences between the mines and the home environment, as well as differences (such as breathing rates) between miners and the general public, there was a need to directly evaluate effects of radon in homes. Seven major residential case-control radon studies have been conducted in North America to directly examine the association between prolonged radon progeny (radon) exposure and lung cancer. Six of the studies were performed in the United States including studies in New Jersey, Missouri (two studies), Iowa, and the combined states study (Connecticut, Utah, and southern Idaho). The seventh study was performed in Winnipeg, Manitoba, Canada. The residential case-control studies performed in the United States were previously reviewed elsewhere (Field, 2001). The goal of this review is to provide additional details regarding the methodologies and findings for the individual studies. Radon concentration units presented in this review adhere to the types (pCi/L or Bq/m3) presented in the

  1. Accounting for error due to misclassification of exposures in case-control studies of gene-environment interaction.

    PubMed

    Zhang, Li; Mukherjee, Bhramar; Ghosh, Malay; Gruber, Stephen; Moreno, Victor

    2008-07-10

    We consider analysis of data from an unmatched case-control study design with a binary genetic factor and a binary environmental exposure when both genetic and environmental exposures could be potentially misclassified. We devise an estimation strategy that corrects for misclassification errors and also exploits the gene-environment independence assumption. The proposed corrected point estimates and confidence intervals for misclassified data reduce back to standard analytical forms as the misclassification error rates go to zero. We illustrate the methods by simulating unmatched case-control data sets under varying levels of disease-exposure association and with different degrees of misclassification. A real data set on a case-control study of colorectal cancer where a validation subsample is available for assessing genotyping error is used to illustrate our methods.

  2. Multicenter Evaluation of a Novel Automated Rapid Detection System of BRAF Status in Formalin-Fixed, Paraffin-Embedded Tissues.

    PubMed

    Schiefer, Ana-Iris; Parlow, Laura; Gabler, Lisa; Mesteri, Ildiko; Koperek, Oskar; von Deimling, Andreas; Streubel, Berthold; Preusser, Matthias; Lehmann, Annika; Kellner, Udo; Pauwels, Patrick; Lambin, Suzan; Dietel, Manfred; Hummel, Michael; Klauschen, Frederick; Birner, Peter; Möbs, Markus

    2016-05-01

    The mutated BRAF oncogene represents a therapeutic target in malignant melanoma. Because BRAF mutations are also involved in the pathogenesis of other human malignancies, the use of specific BRAF inhibitors might also be extended to other diseases in the future. A prerequisite for the clinical application of BRAF inhibitors is the reliable detection of activating BRAF mutations in routine histopathological samples. In a multicenter approach, we evaluated a novel and fully automated PCR-based system (Idylla) capable of detecting BRAF V600 mutations in formalin-fixed, paraffin-embedded tissue within 90 minutes with high sensitivity. We analyzed a total of 436 samples with the Idylla system. Valid results were obtained in 421 cases (96.56%). Its performance was compared with conventional methods (pyrosequencing or Sanger sequencing). Concordant results were obtained in 406 cases (96.90%). Reanalysis of eight discordant samples by next-generation sequencing and/or pyrosequencing with newly extracted DNA and the BRAF RGQ Kit confirmed the Idylla result in seven cases, resulting in an overall agreement of 98.57%. In conclusion, the Idylla system is a highly reliable and sensitive platform for detection of BRAF V600 mutations in formalin-fixed, paraffin-embedded material, providing an efficient alternative to conventional diagnostic methods, particularly for routine diagnostics laboratories with limited experience in molecular pathology.

  3. Vitamin C Intake and Pancreatic Cancer Risk: A Meta-Analysis of Published Case-Control and Cohort Studies

    PubMed Central

    Hua, Yong-Fei; Wang, Gao-Qing; Jiang, Wei; Huang, Jing; Chen, Guo-Chong; Lu, Cai-De

    2016-01-01

    Background Observational studies inconsistently reported the relationship between vitamin C intake and risk of pancreatic cancer. We conducted a meta-analysis of published case-control and cohort studies to quantify the association. Methods Potentially eligible studies were found on PubMed and EMBASE databases through May 31, 2015. A random-effects model was assigned to compute summary point estimates with corresponding 95% confidence intervals (CIs). Subgroup and meta-regression analyses were also performed to explore sources of heterogeneity. Results Our final analyses included 20 observational studies comprising nearly 5 thousand cases of pancreatic cancer. When comparing the highest with the lowest categories of vitamin C intake, the summary odds ratio/relative risk for case-control studies (14 studies), cohort studies (6 studies) and all studies combined was 0.58 (95% CI: 0.52–0.66), 0.93 (95% CI: 0.78–1.11) and 0.66 (95% CI: 0.58–0.75), respectively. The difference in the findings between case-control and cohort studies was statistically significant (P < .001). Possible publication bias was shown in the meta-analysis of case-control studies. Conclusion There is insufficient evidence to conclude any relationship between vitamin C intake and risk of pancreatic cancer. The strong inverse association observed in case-control studies may be affected by biases (eg, recall and selection biases) that particularly affect case-control studies and/or potential publication bias. Future prospective studies of vitamin C intake and pancreatic cancer are needed. PMID:26859881

  4. Tea drinking habits and osteoporotic hip/femur fractures: A case-control study

    PubMed Central

    Huang, Chenshu; Tang, Rongrui

    2016-01-01

    Objective: To explore the relationship between tea drinking habits and osteoporotic hip/femur fractures. Methods: Paired case-control method was used for face-to-face interviews from January 2010 to June 2014. Patients (n=435) with newly osteoporotic hip/femur fracture and 435 controls with the same gender and age (±3) were given questionnaire survey. The survey content included general situation, detailed tea drinking and other diet condition, health-related behavior and family history of fractures, etc. Results: Single factor logistic analysis showed that the habit of drinking tea can significantly reduce the risk of hip/femur fracture. Cumulative year of tea drinking, the cumulative amount of tea and tea concentration (low dose group) have the maximum protection for fracture, while the high dose group is weaker in protection (trend test, P<0.05). After adjustment for age, energy, BMI, education degree, parents’ history of fracture, second hand smoke exposure, calcium supplements, and equivalent energy consumption of physical activity, etc, the above association still showed significant linear trend, but the associated strength was slightly reduced. But stratified analysis found that the effect of tea drinking was only statistically significant in men. And there were no statistically significant differences of people with different education degree. Conclusions: Regular tea drinking can reduce the risk of osteoporotic hip/femur fractures in middle-aged and elderly men. PMID:27182250

  5. Herb-Induced Liver Injury in the Berlin Case-Control Surveillance Study

    PubMed Central

    Douros, Antonios; Bronder, Elisabeth; Andersohn, Frank; Klimpel, Andreas; Kreutz, Reinhold; Garbe, Edeltraut; Bolbrinker, Juliane

    2016-01-01

    Herb-induced liver injury (HILI) has recently attracted attention due to increasing reports of hepatotoxicity associated with use of phytotherapeutics. Here, we present data on HILI from the Berlin Case-Control Surveillance Study. The study was initiated in 2000 to investigate the serious toxicity of drugs including herbal medicines. Potential cases of liver injury were ascertained in more than 180 Departments of all 51 Berlin hospitals from October 2002 to December 2011. Drug or herb intake was assessed through a standardized face-to-face interview. Drug or herbal aetiology was assessed based on the updated Council for International Organizations of Medical Sciences scale. In ten of all 198 cases of hepatotoxicity included in the study, herbal aetiology was assessed as probable (once ayurvedic herb) or possible (Valeriana five times, Mentha piperita once, Pelargonium sidoides once, Hypericum perforatum once, Eucalyptus globulus once). Mean age was 56.4 ± 9.7 years, and the predominant pattern of liver injury was hepatocellular. No cases of acute liver failure or death were observed. This case series corroborates known risks for ayurvedic herbs, supports the suspected association between Valeriana use and liver injury, and indicates a hepatotoxic potential for herbs such as Pelargonium sidoides, Hypericum perforatum or Mentha piperita that were rarely associated with liver injury before. However, given that possible causality does not prove clinical significance, further studies in this field are needed. PMID:26784183

  6. Occupational risk factors for brain cancer: a population-based case-control study in Iowa.

    PubMed

    Zheng, T; Cantor, K P; Zhang, Y; Keim, S; Lynch, C F

    2001-04-01

    A number of occupations and industries have been inconsistently associated with the risk of brain cancer. To further explore possible relationships, we conducted a population-based case-control study of brain glioma in the state of Iowa, involving 375 histologically confirmed incident cases and 2434 population-based controls. Among men, the industries and/or occupations that had a significantly increased risk for employment of more than 10 years included roofing, siding, and sheet metalworking; newspaper work; rubber and plastics products, particularly tires and inner tubes; miscellaneous manufacturing industries; wholesale trade of durable goods, grain, and field beans; cleaning and building service occupations; miscellaneous mechanics and repairers; and janitors and cleaners. Subjects who worked in plumbing, heating, and air conditioning; electrical services; gasoline service stations; and military occupations also experienced a significantly increased risk. Among women, significant excess risk was observed for occupations in agricultural services and farming, apparel and textile products, electrical and electronic equipment manufacturing, various retail sales, record-keeping, and restaurant service. Workers in industries with a potential for gasoline or motor exhaust exposures experienced a non-significant excess risk of brain glioma.

  7. Dietary Inflammatory Index and Risk of Colorectal Cancer: A Case-Control Study in Korea

    PubMed Central

    Cho, Young Ae; Lee, Jeonghee; Oh, Jae Hwan; Shin, Aesun; Kim, Jeongseon

    2016-01-01

    The role of diet-associated inflammation in colorectal cancer is of interest. Accordingly, we aimed to examine whether the dietary inflammatory index (DII) was associated with the risk of colorectal cancer in a case-control study conducted in Korea. The DII was based on dietary intake, which was determined by a 106-item semi-quantitative food frequency questionnaire completed by 923 colorectal cancer cases and 1846 controls. Logistic regression was used to estimate odd ratios (ORs) and 95% confidence intervals (CIs). Subgroup analyses were conducted by the anatomical site of the cancer, sex, and other risk factors. Higher DII scores were associated with an increased incidence of colorectal cancer (OR (95% CI) = 2.16 (1.71, 2.73) for highest vs. lowest tertile). The magnitude differed by anatomical site and sex. This association was slightly weaker in subjects with proximal colon cancer (1.68 (1.08, 2.61)) and was stronger in women (2.50 (1.64, 3.82)). Additionally, stronger associations were observed in subjects who were older than 50 years (p for interaction = 0.004) and engaged in physical activity (p for interaction < 0.001). Results from this study suggest that diet-associated inflammation may increase the risk of colorectal cancer, and this effect may differ by certain factors, such as anatomical site, age, sex, and lifestyle. PMID:27483316

  8. Urinary Prostaglandin E2 Metabolite and Pancreatic Cancer Risk: Case-Control Study in Urban Shanghai

    PubMed Central

    Zhao, Jing; Wang, Jing; Du, Jinfeng; Xu, Hongli; Zhang, Wei; Ni, Quan-Xing; Yu, Herbert; Risch, Harvey A.; Gao, Yu-Tang; Gao, Ying

    2015-01-01

    Pancreatic cancer has been increasing in importance in Shanghai over the last four decades. The etiology of the disease is still unclear. Evidence suggests that the COX-2 pathway, an important component of inflammation, may be involved in the disease. We aimed to evaluate the association between urinary prostaglandin E2 metabolite (PGE-M) level and risk of pancreatic cancer. From a recent population-based case-control study in Shanghai, 200 pancreatic ductal adenocarcinoma cases and 200 gender- and age- frequency matched controls were selected for the present analysis. Urinary PGE-M was measured with a liquid chromatography/mass spectrometric assay. Adjusted unconditional logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). A positive association was observed between PGE-M leve and pancreatic cancer risk: OR = 1.63 (95% CI 1.01–2.63) for the third tertile compared to the first. Though the interactions were not statistically significant, the associations tended to be stronger among subjects with diabetes history (OR = 3.32; 95% CI 1.20–9.19) and higher meat intake (OR = 2.12; 95% CI 1.10–4.06). The result suggests that higher urinary PGE-M level may be associated with increased risk of pancreatic ductal adenocarcinoma. PMID:25679523

  9. A population-based case-control study of isolated anophthalmia and microphthalmia.

    PubMed

    Vogt, Gábor; Puhó, Erzsébet; Czeizel, Andrew E

    2005-01-01

    The purpose of the study was to reveal the etiological factors in the origin of isolated an/microphthalmia. The dataset of the Hungarian Case-Control Surveillance of Congenital Abnormalities, 1980-2002 containing 56 cases with isolated an/microphthalmia and 22,744 malformed controls with other non-ocular defects from the Hungarian Congenital Abnormality Registry, in addition of 56 matched control pairs and 37,837 population controls without defects from the National Birth Registry, was evaluated. Exposure data and family history were collected (i) prospectively by prenatal logbook and other medical records, (ii) retrospectively through a structured questionnaire filled-in by mothers, and (iii) information obtained by regional nurses at home visit of non-respondent mothers. The autosomal recessive origin of isolated an/microphthalmia was indicated in about 10% of cases on the basis of sib recurrence. Cases with isolated an/microphthalmia had a much shorter mean gestational age and smaller mean birth weight, a much larger proportion of preterm birth and low birthweight. Their mothers were younger with a predominance of first birth order, frequently unmarried with low socioeconomic status. These findings are in agreement with a much higher prevalence at birth of cases with isolated an/microphthalmia in the gypsy population probably due to the interaction of inbreeding effect and low socioeconomic status. Further molecular genetic studies are needed to identify gene mutations of isolated an/microphthalmia in the Hungarian gypsy population.

  10. A case-control study between interleukin-10 gene variants and periodontal disease in dogs.

    PubMed

    Albuquerque, Carlos; Morinha, Francisco; Requicha, João; Dias, Isabel; Guedes-Pinto, Henrique; Viegas, Carlos; Bastos, Estela

    2014-04-10

    Periodontal disease (PD) refers to a group of inflammatory diseases that affect the periodontium, the organ which surrounds and supports the teeth. PD is a highly prevalent disease with a multifactorial etiology and, in humans the individual susceptibility is known to be strongly determined by genetic factors. Several candidate genes have been studied, namely genes related with molecules involved in the inflammatory response. Interleukin-10 (IL-10) is a cytokine with important anti-inflammatory and immunomodulatory roles, and several studies indicate an association between IL10 polymorphisms and PD. In dogs, an important animal model in periodontology, PD is also a highly prevalent naturally occurring disease, and only now are emerging the first studies evaluating the genetic predisposition. In this case-control study, a population of 90 dogs (40 dogs with PD and 50 healthy dogs) was used to study the IL10 gene, and seven new genetic variations in this gene were identified. No statistically significant differences were detected in genotype and allele frequencies of these variations between the PD cases and control groups. Nevertheless, one of the variations (IL10/2_g.285G>A) leads to an amino acid change (glycine to arginine) in the putative signal peptide, being predicted a potential influence on IL-10 protein functionality. Further investigations are important to clarify the biological importance of these new findings. The knowledge of these genetic determinants can help to understand properly the complex causal pathways of PD, with important clinical implications. PMID:24487092

  11. [Aeromonas spp asociated to acute diarrheic disease in Cuba: case-control study].

    PubMed

    Bravo, Laura; Fernández, Anabel; Núñez, Fidel Á; Rivero, Luis A; Ramírez, Margarita; Aguila, Adalberto; Ledo, Yudith; Cruz, Yanaika; Hernández, Jenny

    2012-02-01

    The members of the genus Aeromonas are currently considered important gastrointestinal pathogens in different geographical areas. From February 1985 to January 2005 several case-control studies were coordinated by the National Reference Laboratory for Diarrheal Diseases from the Pedro Kouri Institute. The study purpose was to analyze a possible pathogenic role for Aeromonas spp in Cuban children with acute diarrhea. In that period 2,322 children less than 5 years old with acute diarrhea were studied for diarhoeal pathogens and another group of 2,072 non hospitalized children without diarrhea during the similar time from the same geographical areas and matched by ages were recruited. In the group of children with diarrheas (cases), Aeromonas spp. was isolated in 166 (7.15%) and in the control group the microorganism was found in only 35 (1.76%). When Aeromonas isolation rates were compared between both groups, we found that probability to isolate this specie was significantly higher in cases than in controls (OR = 4.48, 95% IC: 3.05-6.60; P < 0.001). The Aeromonas species more frequently isolated were A. caviae, A. hydrophila, and A. veronii bv sobria. Other enteric pathogens detected in children with diarrhea were: Shigella spp in 418 (18%) (P < 0.0001), Salmonella spp in 53 (2.3%) (P < 0.01), and enteropathogenic E. coli in 58 (2.49%) (P < 0.05).

  12. Prevalence of Small Intestinal Bacterial Overgrowth among Chronic Pancreatitis Patients: A Case-Control Study

    PubMed Central

    Bouchard, Simon; Sidani, Sacha

    2016-01-01

    Background. Patients with chronic pancreatitis (CP) exhibit numerous risk factors for the development of small intestinal bacterial overgrowth (SIBO). Objective. To determine the prevalence of SIBO in patients with CP. Methods. Prospective, single-centre case-control study conducted between January and September 2013. Inclusion criteria were age 18 to 75 years and clinical and radiological diagnosis of CP. Exclusion criteria included history of gastric, pancreatic, or intestinal surgery or significant clinical gastroparesis. SIBO was detected using a standard lactulose breath test (LBT). A healthy control group also underwent LBT. Results. Thirty-one patients and 40 controls were included. The patient group was significantly older (53.8 versus 38.7 years; P < 0.01). The proportion of positive LBTs was significantly higher in CP patients (38.7 versus 2.5%: P < 0.01). A trend toward a higher proportion of positive LBTs in women compared with men was observed (66.6 versus 27.3%; P = 0.056). The subgroups with positive and negative LBTs were comparable in demographic and clinical characteristics, use of opiates, pancreatic enzymes replacement therapy (PERT), and severity of symptoms. Conclusion. The prevalence of SIBO detected using LBT was high among patients with CP. There was no association between clinical features and the risk for SIBO. PMID:27446865

  13. Diet as risk for lung cancer: a Swedish case-control study.

    PubMed

    Axelsson, Gosta; Rylander, Ragnar

    2002-01-01

    A case-control study was undertaken to study lung cancer in relation to dietary habits, occupational exposure, and living in urban or country areas. Suspect lung cancer cases in West Sweden and population controls were interviewed using a food frequency questionnaire. The study comprised 177 female and 359 male cases and 916 controls. The cases mainly comprised former and current smokers (82% female, 95% male). For the analysis, cases were divided into the histological diagnoses adenocarcinoma and squamous cell, small cell, and adenosquamous cell carcinomas, as well as into smoking categories. A high frequency of consumption of vegetables was significantly related to a lower risk for adenocarcinoma and squamous cell and adenosquamous cell carcinoma among men and adenocarcinoma among women. A low odds ratio in the highest quartile of vegetable consumption in men was seen in all smoking categories. There were no significant protective effects from fruit in the different lung cancer subgroups, although a significant trend was found for heavy-smoking females. A high consumption of milk was related to an increased risk for lung cancer, especially adenosquamous cell carcinoma. The results suggest that the protective effect or risk due to dietary factors may affect different forms of lung cancer. The results from this as well as previous studies suggest a complex interaction between diet and lung cancer risk, involving the types of lung cancer as well as consumption patterns in the population.

  14. Case-control assessment of diet and lung cancer risk in African Americans and Mexican Americans.

    PubMed

    Pillow, P C; Hursting, S D; Duphorne, C M; Jiang, H; Honn, S E; Chang, S; Spitz, M R

    1997-01-01

    In this case-control study we determined whether dietary differences underlie some of the ethnic and sex differences in US lung cancer rates. We examined the relationship between diet and lung cancer development in 137 lung cancer cases (93 African Americans and 44 Mexican Americans) and 187 controls (78 African Americans and 109 Mexican Americans). Cases reported a higher daily mean total fat intake (p < 0.001), whereas controls had a higher daily mean intake of dietary fiber (p < 0.001) and fruits (p = 0.02). Ethnic differences in diet were also observed: Mexican Americans consumed less total fat (p < 0.02) and more fiber (p < 0.001) and vegetables (p = 0.08) than African Americans. Additionally, men consumed more total fat (p = 0.08) and less fiber (p = 0.001), fruits (p < 0.001), and vegetables (p = 0.002) than women. Multivariable analysis, after adjustment for the effects of pack-years of smoking, age, total energy intake, sex, and ethnicity, demonstrated a positive association between high total fat consumption and lung cancer risk (p < 0.01) and an inverse association between high fruit consumption and lung cancer risk (p = 0.05). In conclusion, our findings support the hypothesis that diet, particularly high fat consumption and low fruit and vegetable consumption, contributes (independent of cigarette smoking) to the excess lung cancer risk in African-American men, who have the highest lung cancer rates in the United States.

  15. Fruit and vegetable consumption and lung cancer risk: a case-control study in Galicia, Spain.

    PubMed

    Tarrazo-Antelo, Ana Marina; Ruano-Ravina, Alberto; Abal Arca, José; Barros-Dios, Juan Miguel

    2014-01-01

    Lung cancer has multiple risk factors and tobacco is the main one. Diet plays a role, but no clear effect has been consistently observed for different fruit and vegetable consumption. We aim to assess the association between fruit and vegetable consumption and lung cancer risk through a hospital-based case-control study in Spanish population. We recruited incident lung cancer cases in 2 Spanish hospitals from 2004 to 2008. Controls were individuals attending hospital for trivial surgery. Cases and controls were older than 30 and did not have a neoplasic history. We collected information on lifestyle with special emphases on tobacco and dietary habits. We included 371 cases and 496 controls. We found no protective effect for overall fruit consumption. For green leafy vegetables, the odds ratio (OR) was 0.92 [95% confidence interval (CI) = 0.32-2.69), and for other vegetables the OR was 0.77 (95% CI = 0.40-1.48) for the categories compared. We observed a reduced risk for broccoli and pumpkin intake. Although fruit consumption does not seem to be associated with a lower lung cancer risk, only the frequent consumption of specific green leafy vegetables and other vegetables might be associated with a reduced risk of lung cancer.

  16. A case-control study of risk factors for sporadic campylobacter infections in Denmark.

    PubMed Central

    Neimann, J.; Engberg, J.; Mølbak, K.; Wegener, H. C.

    2003-01-01

    A case control study comprising 282 cases and 319 matched controls was conducted in Denmark during 1996-7. Two estimates of the odds ratio (OR) were determined for each risk factor with and without 'protective factors' fitted into the final model. Consumption of undercooked poultry (OR 4.5; 8.2), consumption of red meat at a barbecue (OR 2.3; 4.1), consumption of grapes (OR 1.6; 2.8) and drinking unpasteurized milk (OR 2.3; 11.8) were identified as risk factors in both models. Frequent consumption of pork chops (OR 4.4) and daily contact with domestic animals and pets were identified as risk factors in one of the two models only. Finally, foreign travel was found to be a significant risk factor (OR 2.5). Seasonal and regional interaction was observed for several risk factors and the time elapsed from interviewing of cases to interviewing of controls seemed to influence the effect of certain seasonal dependent risk factors. PMID:12825719

  17. Consultation for Small-Sized Penis in the Egyptian Males: A Case Control Study.

    PubMed

    Salama, Nader

    2016-05-01

    This study aimed to report penile dimensions in adult Egyptian males consulting for small-sized penis (SSP) and describe their demographics and andrological profile. A case control study was designed through retrospective data analysis of patients (n = 239) seeking advice for SSP and a control group (n = 59). This included sociodemographics, other andrological complaints, and penile dimensions (pendulous length [PL], penopubic or total length [TL], and circumference [CF]) at flaccid and erect states and the size of the prepubic fatty pad. The results reported that most patients were single, students, and smokers and had not completed a university education. Several patients reported falsely premature ejaculation (PE), penile curvature (PC), and small-sized testes. Most penile dimensions of the patients (mean, cm) were significantly lower than those of the controls, whether in flaccid (PL: 7.4 vs. 8.05, p = .008; CF: 8.7 vs. 8.98, p = .026) or erect state (PL: 11.8 vs. 13, p = .000; TL: 14.2 vs. 15, p = .000; CF: 11.3 vs. 11.8, p = .003). However, no patient presented with a pendulous penile length <4 cm in flaccid or <7 cm in erect state. In conclusion, Egyptian men consulting for SSP did not have true small organs, but their penile dimensions were slightly smaller than those of men without such complaint. The proper sexual education program is highly advisable in these situations to avoid the myths and misconceptions about sexuality.

  18. Risk Factors for Sporadic Pancreatic Neuroendocrine Tumors: A Case-Control Study

    PubMed Central

    Ben, Qiwen; Zhong, Jie; Fei, Jian; Chen, Haitao; Yv, Lifen; Tan, Jihong; Yuan, Yaozong

    2016-01-01

    The current study examined risk factors for sporadic pancreatic neuroendocrine tumors (PNETs), including smoking, alcohol use, first-degree family history of any cancer (FHC), and diabetes in the Han Chinese ethnic group. In this clinic-based case-control analysis on 385 patients with sporadic PNETs and 614 age- and sex-matched controls, we interviewed subjects using a specific questionnaire on demographics and potential risk factors. An unconditional multivariable logistic regression analysis was used to estimate adjusted odds ratios (AORs). No significant differences were found between patients and controls in terms of demographic variables. Most of the patients with PNETs had well-differentiated PNETs (G1, 62.9%) and non-advanced European Neuroendocrine Tumor Society (ENETS) stage (stage I or II, 83.9%). Ever/heavy smoking, a history of diabetes and a first-degree FHC were independent risk factors for non-functional PNETs. Only heavy drinking was found to be an independent risk factor for functional PNETs (AOR = 1.87; 95% confidence interval [CI], 1.01–3.51). Ever/heavy smoking was also associated with advanced ENETS staging (stage III or IV) at the time of diagnosis. This study identified first-degree FHC, ever/heavy smoking, and diabetes as risk factors for non-functional PNETs, while heavy drinking as a risk factor for functional PNETs. PMID:27782199

  19. Case-control study on the prevention of occupational eye injuries.

    PubMed

    Ho, Chi-Kung; Yen, Ya-Lin; Chang, Cheng-Hsien; Chiang, Hung-Che; Shen, Ying-Ying; Chang, Po-Ya

    2008-01-01

    The risk factors for occupational eye injuries have never been published in Taiwan. We conducted a case-control study to analyze the differences among workers on their knowledge, attitude to and practice (KAP) of occupational accident prevention. In the study, a statistical model was also set up for predicting the occupational problem. Subjects, including 31 cases of work-related eye injuries and 62 controls, completed a structured questionnaire on KAP, which revealed that 80.6% and 62.7% of workers in the case and control groups, respectively, did not wear eye protection during work. Furthermore, we found that temporary employment (OR, 10.7; 95% CI, 3.03-36.16) and fewer than 10 years of education (OR, 4.44; 95% CI, 1.73-11.44) were the major risk factors for occupational eye injuries. In addition, we developed a logistic regression model with four predictors (temporary employment, education years less than 10, poor management of industrial health and safety in the workplace, and poor attitude towards accident prevention) for the occurrence of occupational eye injuries. In conclusion, in Taiwan, compulsory regulation of wearing eye protection during work, good education, management of work safety and hygiene and employee (especially temporary worker) commitment to safety and health are strongly recommended prevention strategies.

  20. A Case-Control Study of Risk Factors Associated with Scrub Typhus Infection in Beijing, China

    PubMed Central

    Zhang, Liqin; Dou, Xiangfeng; Wang, Xiaomei; Li, Weihong; Zhang, Xiuchun; Sun, Yulan; Guan, Zengzhi; Li, Xinyu; Wang, Quanyi

    2013-01-01

    To investigate the risk factors of scrub typhus infection in Beijing, China, a case-control study was carried out. Cases (n = 56) were defined as persons who were diagnosed by PCR and serological method within three years. Three neighborhood control subjects were selected by matching for age and occupation. Living at the edge of the village, living in the houses near grassland, vegetable field or ditch, house yard without cement floor, piling weeds in the house or yard, all of these were risk factors for scrub typhus infection. Working in vegetable fields and hilly areas, and harvesting in autumn posed the highest risks, with odds ratios (ORs) and 95% confidence intervals (CIs) of 3.7 (1.1–11.9), 8.2 (1.4–49.5), and 17.2 (5.1–57.9), respectively. These results would be useful for the establishment of a detail control strategy for scrub typhus infection in Beijing, China. PMID:23691083

  1. Predictive factors of death in patients with tuberculosis: a nested case-control study.

    PubMed

    Moosazadeh, M; Nezammahalleh, A; Movahednia, M; Movahednia, N; Khanjani, N; Afshari, M

    2015-06-09

    Tuberculosis is one of the main causes of death worldwide. This study aimed to determine predictive factors for death in patients with tuberculosis to set priorities for public heath interventions to reduce mortality in these patients. This nested case-control study was carried out in Mazandaran province of Islamic Republic of Iran among tuberculosis patients who were treated during 2002-2009. Each deceased patient was individually matched with a control patient according to sex, age, area of involvement and time of follow-up. Potential risk factors for death were evaluated using multivariate conditional logistic regression models. From 2206 patients 376 cases and 376 matched controls were selected. Only positive serology for HIV (OR = 19.1), history of kidney disease (OR = 6.81) and use of immunosuppressant drugs (OR = 3.96) significantly increased the risk of death in tuberculosis patients. These potentially modifiable risk factors could be taken into account in preventive interventions for tuberculosis patients in our country.

  2. A case-control study on fat-to-muscle ratio and risk of breast cancer.

    PubMed

    Ronco, Alvaro L; Boeing, Heiner; De Stefani, Eduardo; Schulz, Mandy; Schulze, Matthias; Pischon, Tobias

    2009-01-01

    Our objective was to analyze detailed anthropometric characterization for risk of breast cancer in Uruguayan women. The design was a case-control study. The setting was Pereira Rossell Women's Hospital, Montevideo, Uruguay. Subjects were 343 incident breast cancer cases and 1,042 frequency-matched healthy controls who were interviewed on menstrual and reproductive story; and a series of skin folds, circumferences, and diameters were measured to calculate fat and muscle fractions and the derived fat-to-muscle ratio (FMR). Odds ratio (ORs) coefficients were taken as estimates of relative risk derived from unconditional logistic regression. Muscle fraction was negatively associated with risk [OR for highest quartile = 0.23, 95% confidence interval (CI) = 0.15-0.34], fat fraction was positively associated (OR = 3.90, 95% CI = 2.62-5.80), and FMR was positively associated (OR = 4.45, 95% CI = 2.99-6.62). Stratified analyses by body mass index levels also showed risk increases for the highest tertiles of FMR, always displaying significant linear trends. Since increases of risk were found in overweight and in normal weight women, results suggest that fractions and amount of muscle and fat components might be risk factors for breast cancer on the basis of currently existing metabolic and immune interrelationships between adipose and muscular tissue given by glutamine, exercise-derived myokines, and other cytokines produced by these tissues. PMID:19838918

  3. Childhood leukemia and parental occupation: a register-based case-control study

    SciTech Connect

    Van Steensel-Moll, H.A.; Valkenburg, H.A.; Van Zanen, G.E.

    1985-02-01

    To explore possible etiologic factors of childhood leukemia, a case-control study was performed in the Netherlands. Cases were selected from a complete nationwide register of cases of childhood leukemia which were diagnosed between 1973 and 1980. Controls were matched with cases for year of birth, sex, and place of residence at the time of diagnosis. Information about possible exposure was collected by a postal questionnaire addressed to the parents. This report concerns the results of the analysis of parental occupations and occupational exposures for 519 children with acute lymphocytic leukemia and 507 controls. During pregnancy, more mothers of patients were working in ''hydrocarbon-related'' occupations; relative risk (RR) = 2.5 (95% confidence interval (CI) = 0.7 - 9.4). Likewise, greater occupational exposure to chemicals (paint, petroleum products, and unspecified chemicals) during pregnancy was found for mothers of patients (RR = 2.4, 95% CI = 1.2 - 4.6). The kind of work being performed by the mothers one year before diagnosis did not differ between cases and controls. For the fathers, no relationship was found between a hydrocarbon-related occupation or occupational exposure to chemicals and leukemia in the offspring. Adjustment for birth order, social class, and degree of urbanization did not materially change the relative risks. 16 references, 5 tables.

  4. Breast Cancer Risk Factors among Ugandan Women at a Tertiary Hospital: A Case-Control Study

    PubMed Central

    Galukande, Moses; Wabinga, Henry; Mirembe, Florence; Karamagi, Charles; Asea, Alexzander

    2016-01-01

    Background Although East Africa, like other countries in sub-Saharan Africa, has a lower incidence of breast cancer than high-income countries, the disease rate is rising steeply in Africa; it has nearly tripled in the past few decades in Uganda. There is a paucity of studies that have examined the relation between reproductive factors and breast cancer risk factors in Ugandan women. Objective To determine breast cancer risk factors among indigenous Ugandan women. Methods This is a hospital-based unmatched case-control study. Interviews were conducted between 2011 and 2012 using structured questionnaires. Patients with histologyproven breast cancer were recruited over a 2-year period. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). Results A total of 350 women were recruited; 113 were cases and 237 were controls. The mean age was 47.5 years (SD 14) for the cases and 45.5 years (SD 14.1) for the controls. The odds of breast cancer risk seemed lower for those who breastfed (adjusted OR = 0.04; 95% CI: 0.01, 0.18). There was no significance for early age at first full-term birth (adjusted OR = 1.96; 95% CI: 0.97, 3.96; p = 0.061), and urban residence carried no increased odds of breast cancer either (p = 0.201). Conclusion Breastfeeding seems to be associated with reduced odds of breast cancer. PMID:27104645

  5. Dietary vitamin A and lung cancer: results of a case-control study among chemical workers

    SciTech Connect

    Bond, G.G.; Thompson, F.E.; Cook, R.R.

    1987-01-01

    A nested case-control study conducted among a cohort of chemical manufacturing employees provided an opportunity to test the hypothesis that lung cancer risk is inversely related to dietary intake of vitamin A. Eligible for study were 308 former male employees who had died of lung cancer between 1940 and 1980. Two control groups, one a decedent and the other a living series, were individually matched to the cases one-for-one. Interviews were completed with 734 subjects or their next-of-kin and included a food frequency list. A vitamin A index was developed for each subject based on the frequency of consumption of 29 food items. After adjustment for a number of potentially confounding variables (e.g., smoking, educational level, and use of vitamin supplements), there was evidence that vitamin A intake was inversely associated with lung cancer risk. The effect was most pronounced in the comparisons with the living controls and appeared strongest among cigarette smokers. Subjects in the lowest tertile of vitamin A intake had approximately twice the risk of lung cancer as those in the highest. Analyses of an index of carotenoids and of individual food items suggested that plant sources of vitamin A may play a more important role in producing the effect than do animal sources.

  6. Multiple myeloma and exposure to pesticides: a Canadian case-control study.

    PubMed

    Pahwa, Punam; Karunanayake, Chandima P; Dosman, James A; Spinelli, John J; McDuffie, Helen H; McLaughlin, John R

    2012-01-01

    The objective of this study was to investigate the putative associations of specific pesticides with multiple myeloma. A matched, population-based, case-control study was conducted among men residing in six Canadian provinces (Quebec, Ontario, Manitoba, Saskatchewan, Alberta, and British Columbia). Data were collected on 342 multiple myelome cases and 1506 age and province of residence matched controls. Data were collected by mailed questionnaires to capture demographic characteristics, antecedent medical history, detailed lifetime occupational history, smoking history, family history of cancer, and exposure to broadly characterized pesticides at home, work, and practicing hobbies. Details of pesticide exposures were collected by telephone interview for those who reported 10 hours or more per year of exposure. Exposure to pesticides grouped into major chemical classes resulted in increased risk being detected only for carbamate insecticides [odds ratio (OR) and 95% confidence interval (CI) 1.90 (1.11, 3.27) adjusted for potential confounders]. An exposure to fungicide captan [2.35 (1.03, 5.35)] was positively associated with the incidence of multiple myeloma. While an exposure to carbaryl [1.89 (0.98, 3.67)] was associated with the incidence of multiple myelome with borderline significance. The authors further suggest that certain pesticide exposures may have a role in multiple myeloma etiology, and identify specific factors warranting investigation in other populations.

  7. High Prevalence of Human Papillomavirus in Colorectal Cancer in Hispanics: A Case-Control Study

    PubMed Central

    Bernabe-Dones, Raul D.; Gonzalez-Pons, Maria; Villar-Prados, Alejandro; Lacourt-Ventura, Mercedes; Rodríguez-Arroyo, Heriberto; Fonseca-Williams, Sharon; Velazquez, Francisco E.; Diaz-Algorri, Yaritza; Lopez-Diaz, Sofia M.; Rodríguez, Nayra; Yamamura, Yasuhiro; Cruz-Correa, Marcia

    2016-01-01

    The role of Human Papillomavirus (HPV) in colorectal carcinogenesis remains elusive. Based on the high incidence of HPV-associated malignancies among Puerto Rican Hispanics, this study aimed to assess the prevalence of HPV infection and viral integration in colorectal tissues in order to evaluate its putative role in colorectal cancer (CRC). In this case-control study, the prevalence of HPV infection in CRC (cases n = 45) and normal colon mucosa from cancer-free subjects (controls n = 36) was assessed by a nested PCR strategy. HPV-16 genotyping was performed in HPV-positive tissues and the physical status of the HPV-16 genome was determined by E2 detection. HPV was detected in 19 of 45 (42.2%) CRC cases (mean age 61.1 ± 10.7 years, 24 males) and in 1 of 36 (2.8%) controls (mean age 60.9 ± 9.6 years, 24 males) with an OR = 25.58 (95% CI 3.21 to 203.49). HPV-16 was detected in 63.2% of the HPV-positive colorectal tumors; genome integration was observed in all HPV-16 positive cases. This is the first report showing the high prevalence of HPV infections in Caribbean Hispanic colorectal tumors. Despite evidence of HPV integration into the host genome, further mechanistic analysis examining HPV oncoprotein expression and the putative role of these oncoproteins in colorectal carcinogenesis is warranted. PMID:26904111

  8. Urinary strontium and the risk of breast cancer: A case-control study in Guangzhou, China

    SciTech Connect

    Chen, Li-Juan; Tang, Lu-Ying; He, Jian-Rong; Su, Yi; Cen, Yu-Ling; Yu, Dan-Dan; Wu, Bang-Hua; Lin, Ying; Chen, Wei-Qing; Song, Er-Wei; Ren, Ze-Fang

    2012-01-15

    Strontium has been widely used in industries like electronic and pharmacy. It has a carcinogenic potential, however, and no study has been conducted to evaluate its effects on cancer risk. The aim of this study was to explore the possible association between strontium and breast cancer risk in a case-control study including 240 incident invasive breast cancer patients and 246 age-matched controls. We measured the urinary concentrations of strontium by inductively coupled plasma mass spectrometry, and conducted face-to-face interviews to obtain information on potential breast cancer risk factors. Multivariable analysis was used to estimate the association. Creatinine-adjusted levels [median (25th, 75th) {mu}g/g] of strontium were 155.59 (99.05, 230.70) in the breast cancer patients and 119.62 (81.97, 163.76) in the controls. Women in the highest tertile of strontium showed 124% increased risk of breast cancer, when compared with those in the lowest tertile after adjustment for the potential risk factors [OR (95% CI): 2.24 (1.42-3.81)]. This association was particularly strong for HER2 positive breast cancer [OR (95% CI): 10.92 (3.53-33.77)], and only occurred among premenopausal women. These results suggest a potential role of strontium in the development of breast cancer and urge further studies on the environmental contamination and the physiological and pathological mechanisms of strontium.

  9. Herb-Induced Liver Injury in the Berlin Case-Control Surveillance Study.

    PubMed

    Douros, Antonios; Bronder, Elisabeth; Andersohn, Frank; Klimpel, Andreas; Kreutz, Reinhold; Garbe, Edeltraut; Bolbrinker, Juliane

    2016-01-01

    Herb-induced liver injury (HILI) has recently attracted attention due to increasing reports of hepatotoxicity associated with use of phytotherapeutics. Here, we present data on HILI from the Berlin Case-Control Surveillance Study. The study was initiated in 2000 to investigate the serious toxicity of drugs including herbal medicines. Potential cases of liver injury were ascertained in more than 180 Departments of all 51 Berlin hospitals from October 2002 to December 2011. Drug or herb intake was assessed through a standardized face-to-face interview. Drug or herbal aetiology was assessed based on the updated Council for International Organizations of Medical Sciences scale. In ten of all 198 cases of hepatotoxicity included in the study, herbal aetiology was assessed as probable (once ayurvedic herb) or possible (Valeriana five times, Mentha piperita once, Pelargonium sidoides once, Hypericum perforatum once, Eucalyptus globulus once). Mean age was 56.4 ± 9.7 years, and the predominant pattern of liver injury was hepatocellular. No cases of acute liver failure or death were observed. This case series corroborates known risks for ayurvedic herbs, supports the suspected association between Valeriana use and liver injury, and indicates a hepatotoxic potential for herbs such as Pelargonium sidoides, Hypericum perforatum or Mentha piperita that were rarely associated with liver injury before. However, given that possible causality does not prove clinical significance, further studies in this field are needed. PMID:26784183

  10. Dietary inflammatory index and endometrial cancer risk in an Italian case-control study.

    PubMed

    Shivappa, Nitin; Hébert, James R; Zucchetto, Antonella; Montella, Maurizio; Serraino, Diego; La Vecchia, Carlo; Rossi, Marta

    2016-01-14

    The relation between inflammation deriving from diet and endometrial cancer risk has not yet been investigated. In this study, we explored the association between the dietary inflammatory index (DII) and endometrial cancer risk in an Italian case-control study. Cases comprised 454 patients with incident, histologically confirmed carcinoma of the endometrium, and controls comprised 908 subjects admitted to the same network of hospitals as cases for a wide spectrum of acute, non-neoplastic conditions. DII scores were computed on the basis of dietary intake assessed using a reproducible and valid seventy-eight-item FFQ. OR were calculated through logistic regression models conditioned on age and study centre and adjusted for recognised confounding factors, including total energy intake. Women with the most pro-inflammatory diet had a higher risk for endometrial cancer compared with women with the most anti-inflammatory diet (OR(Quartile) 4 v. 1 1·46; 95% CI 1·02, 2·11; P(trend)=0·04). A pro-inflammatory diet may increase the risk for endometrial cancer.

  11. Association between chronic periodontitis and rheumatoid arthritis: a hospital-based case-control study.

    PubMed

    Joseph, Rosamma; Rajappan, Sreeraj; Nath, Sameera G; Paul, Binoy J

    2013-01-01

    Rheumatoid arthritis (RA) and chronic periodontitis are the most common chronic inflammatory diseases with remarkable pathological and clinical similarities. A lot of similarities exist between RA and periodontitis at cellular and molecular levels. The relationship between these two chronic inflammatory diseases is still unclear. This case-control study was undertaken to determine the possible association between chronic inflammatory diseases like RA and periodontitis. The case group consisted of 100 patients attending the Rheumatology clinic who have rheumatoid arthritis (RA group). Age- and gender-matched 112 patients without RA attending the Outpatient wing of Department of General Medicine formed the control group (NRA group). The number of missing teeth, gingival index (GI), oral hygiene index-simplified (OHI-S), probing pocket depth (PPD) and clinical attachment levels (CAL) were evaluated in both the groups. Rheumatoid disease activity was assessed by DAS-28 score system. Systemic markers of inflammation like erythrocytic sedimentation rate (ESR) and serum levels of C-reactive protein (CRP) were assessed. There was a statistically significant difference in GI, OHI-S, PPD, CAL, ESR and CRP levels between cases (RA group) and controls (NRA group) (P < 0.05). Among subjects with RA, there was no association between the rheumatoid disease activity and the severity of periodontal disease. The occurrence and severity of periodontitis was found to be higher in RA subjects as compared to subjects without RA, suggesting a positive relation between these two chronic inflammatory diseases.

  12. Genetic analysis of age-at-onset traits based on case-control family data.

    PubMed

    Yip, Benjamin H; Moger, Tron Anders; Pawitan, Yudi

    2010-12-30

    Family studies are a useful alternative to twin studies for disentangling genetic and environmental effects on human diseases. However, although age-at-onset traits are often of interest, family-based quantitative genetic analysis of such data is still not commonly used. One reason is that we need multiple random components to capture the genetic and environmental contributions, so it becomes hard to use the existing frailty models for correlated survival data. In this paper we consider the alternative accelerated failure-time models with random effects. The method allows both left truncation and right censoring, and it can deal with an arbitrary family structure and multiple random components. For estimation we use the h-likelihood procedure, which avoids the integration of the random effects in the marginal likelihood approach. To deal with large cohort data, we propose a case-control scheme, where we ascertain all families with at least two events and a subsample of control families. A pseudo-h-likelihood approach is used to analyse the ascertained data. We study the performance of the method using simulated data, and provide an illustration with analysis of melanoma in the Swedish population.

  13. Clinicopathological features of breast cancers predict the development of leptomeningeal metastases: a case-control study.

    PubMed

    Le Rhun, Emilie; Taillibert, Sophie; Zairi, Fahed; Devos, Patrick; Pierret, Matthieu Faivre; Dubois, François; Assaker, Richard; Buisset, Etienne; Bonneterre, Jacques; Baranzelli, Marie Christine

    2011-11-01

    The incidence of leptomeningeal metastases (LM) in patients with breast cancer (BC) is increasing as a result of increased screening and improved patient survival. However, the median survival time after diagnosis of LM is between 5 weeks (without any treatment) and 5 months (for aggressively treated patients). In an attempt to identify clinicopathological risk factors for LM, we carried out a case-control study of 100 women with BC. Fifty patients with BC and LM were enrolled and an additional 50 patients with BC and no CNS metastases including leptomeningeal spread were selected as controls. Patients who had developed LM were selected between December 2006 and August 2008. The control group was matched for: age at diagnosis, year of diagnosis, and initiation of chemotherapy at BC diagnosis. The ILC type (P = 0.03), ER-negative (P = 0.01) and PR-negative status (P = 0.03), and initial M+ status at BC diagnosis (P = 0.008) tended to be more frequent in LM patients. These characteristics should lead to early appropriate assessments being performed in this targeted population when a neurological complaint appears, in order to detect LM as soon as possible.

  14. Cohort and case-control analyses of workers exposed to vinyl chloride: An update

    SciTech Connect

    Wu, W.A.; Steenland, K.; Brown, D.; Wells, V.; Jones, J.; Schulte, P.; Halperin, W.

    1989-06-01

    The mortality in a cohort of workers at a vinyl chloride polymerization plant has been updated, extending the period of observation in the original study from 1974 to 1986. Workers at this plant may have been exposed to vinyl chloride monomer and/or polyvinyl chloride dust, or may have had no exposure to either substance. Seventy-six percent of the work force worked in jobs with potential exposure to vinyl chloride monomer. Among the total cohort, statistically significant excess risks were observed for liver, lung, and brain cancer. For the subcohort of workers exposed to vinyl chloride monomer, the standardized mortality ratio (SMR) for liver cancer was 333 (90% confidence interval (CI) 202 to 521). However, there were no significant excesses of either brain (SMR = 145, 90% CI 78 to 249) or lung cancer (SMR = 115, 90% CI 96 to 141). To investigate dose response, nested case-control studies for liver, brain, and lung cancer were conducted among the total cohort (including the nonexposed). For these studies there were two exposure variables, cumulative dose of vinyl chloride monomer and cumulative dose of polyvinyl chloride dust. Cumulative dose was defined as the product of level and duration of exposure. The only significant association between disease risk and cumulative dose was for liver cancer and cumulative dose of vinyl chloride monomer. Further division of the liver cancers into angiosarcoma (n = 12) and other liver cancers (n = 7), based on review of death certificates and medical records, showed that the dose response existed only for angiosarcomas.

  15. Cohort and case-control analyses of workers exposed to vinyl chloride: an update.

    PubMed

    Wu, W; Steenland, K; Brown, D; Wells, V; Jones, J; Schulte, P; Halperin, W

    1989-06-01

    The mortality in a cohort of workers at a vinyl chloride polymerization plant has been updated, extending the period of observation in the original study from 1974 to 1986. Workers at this plant may have been exposed to vinyl chloride monomer and/or polyvinyl chloride dust, or may have had no exposure to either substance. Seventy-six percent of the work force worked in jobs with potential exposure to vinyl chloride monomer. Among the total cohort, statistically significant excess risks were observed for liver, lung, and brain cancer. For the subcohort of workers exposed to vinyl chloride monomer, the standardized mortality ratio (SMR) for liver cancer was 333 (90% confidence interval (CI) 202 to 521). However, there were no significant excesses of either brain (SMR = 145, 90% CI 78 to 249) or lung cancer (SMR = 115, 90% CI 96 to 141). To investigate dose response, nested case-control studies for liver, brain, and lung cancer were conducted among the total cohort (including the nonexposed). For these studies there were two exposure variables, cumulative dose of vinyl chloride monomer and cumulative dose of polyvinyl chloride dust. Cumulative dose was defined as the product of level and duration of exposure. The only significant association between disease risk and cumulative dose was for liver cancer and cumulative dose of vinyl chloride monomer. Further division of the liver cancers into angiosarcoma (n = 12) and other liver cancers (n = 7), based on review of death certificates and medical records, showed that the dose response existed only for angiosarcomas.

  16. A Nested Case-Control Study of Association between Metabolome and Hypertension Risk

    PubMed Central

    Hao, Yongchen; Wang, Ying; Xi, Lu; Li, Guoqi; Zhao, Fan; Qi, Yue; Liu, Jing; Zhao, Dong

    2016-01-01

    We aimed to explore novel small metabolites that associated with hypertension risk in a population-based nested case-control study. Among 460 individuals with optimal blood pressure (<120/80 mmHg) at baseline, 55 progressed to hypertension during 5 years of follow-up. Twenty-nine cases of incident hypertension and 29 controls, matched for age, sex, and baseline systolic blood pressure, were included in this study. Serum metabolites were measured by gas chromatography-tandem mass spectrometry. t-test and logistic regression analysis were applied to investigate the association between metabolites and incident hypertension. Among the 241 metabolites identified in this study, baseline levels of 26 metabolites were significantly different between hypertension and control groups. After adjusting for body mass index, smoking, and drinking, 16 out of the 26 metabolites were still associated with hypertension risk including four amino acids. Amino acids were negatively associated with risk of future hypertension, with odds ratio (OR) ranging from 0.33 to 0.53. Two of these amino acids were essential amino acids including threonine and phenylalanine. Higher level of lyxose, a fermentation product of gut microbes, was associated with higher risk of hypertension. Our study identified multiple metabolites that associated with hypertension risk. These findings implied that low amino acid levels and gut microbiome might play an important role in the pathogenesis of hypertension. PMID:27119083

  17. Valid Monte Carlo permutation tests for genetic case-control studies with missing genotypes.

    PubMed

    Kinnamon, Daniel D; Martin, Eden R

    2014-05-01

    Monte Carlo permutation tests can be formally constructed by choosing a set of permutations of individual indices and a real-valued test statistic measuring the association between genotypes and affection status. In this paper, we develop a rigorous theoretical framework for verifying the validity of these tests when there are missing genotypes. We begin by specifying a nonparametric probability model for the observed genotype data in a genetic case-control study with unrelated subjects. Under this model and some minimal assumptions about the test statistic, we establish that the resulting Monte Carlo permutation test is exact level α if (1) the chosen set of permutations of individual indices is a group under composition and (2) the distribution of the observed genotype score matrix under the null hypothesis does not change if the assignment of individuals to rows is shuffled according to an arbitrary permutation in this set. We apply these conditions to show that frequently used Monte Carlo permutation tests based on the set of all permutations of individual indices are guaranteed to be exact level α only for missing data processes satisfying a rather restrictive additional assumption. However, if the missing data process depends on covariates that are all identified and recorded, we also show that Monte Carlo permutation tests based on the set of permutations within strata of individuals with identical covariate values are exact level α. Our theoretical results are verified and supplemented by simulations for a variety of missing data processes and test statistics.

  18. Epidemiological case-control study on the etiology of bladder cancer in Turkey.

    PubMed

    Akdaş, A; Kirkali, Z; Bilir, N

    1990-01-01

    A case-control study of 194 patients with bladder cancer and the same number of age- and sex-matched hospital controls were interviewed to estimate the role of various factors on the etiology of bladder cancer in Turkey. There was a significant difference between the case and control groups on cigarette smoking (p less than 0.001), alcohol intake (p less than 0.001), Turkish coffee consumption (p = 0.01), and artificial sweeteners (p less than 0.05). The risks for alcohol and tobacco users increased in correlation with the duration of exposure. The risk of bladder cancer increased directly with the quantity and frequency of alcohol intake. Alcohol and coffee drinking was found to be a promoting factor when adjusted to smoking habits (p less than 0.05). No statistical comparisons could be made to clarify the risks attributed by occupation and place of residence due to small figures in each group. However, in farmers, there was a significant difference between the cases and controls on the use of artificial fertilizers and insecticides (p less than 0.01). People who were exposed to unspecified chemical substances were more prone to develop bladder cancer (p less than 0.001). We conclude that both personal habits and exogenous carcinogens play a role in the etiology of bladder tumors. PMID:2318234

  19. Splenectomy Correlates With Increased Risk of Acute Pancreatitis: A Case-Control Study in Taiwan

    PubMed Central

    Lai, Shih-Wei; Lin, Cheng-Li; Liao, Kuan-Fu

    2016-01-01

    Objective The objective of the study was to investigate the association between splenectomy and acute pancreatitis. Methods We conducted a case-control study using the database of the Taiwan National Health Insurance Program. We included 7666 subjects aged 20–84 years with first-time acute pancreatitis during the period of 1998–2011 as cases and 30 664 randomly selected subjects without acute pancreatitis as controls. Both cases and controls were matched for sex, age, and index year of acute pancreatitis diagnosis. The association of acute pancreatitis with splenectomy was examined using a multivariable unconditional logistic regression model and reported as an odds ratio and its 95% confidence interval (CI). Results After adjustment for covariables, the adjusted odds ratio of acute pancreatitis was 2.90 for subjects with splenectomy (95% CI, 1.39–6.05) compared with subjects without splenectomy. Conclusions Splenectomy is associated with acute pancreatitis. Further studies are necessary to clarify the underlying mechanism. PMID:27087607

  20. 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. PMID:16696291

  1. Evaluating Bone Health in Egyptian Children with Forearm Fractures: A Case Control Study

    PubMed Central

    Elbatrawy, Salwa; Gobashy, Amr; Moreira, Alvaro

    2016-01-01

    Objective. To determine the likelihood of vitamin D deficiency and low bone mineral density in Egyptian children with forearm fractures. Methods. A case control study of 46 children aged 3 to 10 years with or without forearm fractures. Validated questionnaires were used to assess calcium and vitamin D intake as well as sun exposure. Serum calcium, phosphorus, alkaline phosphatase, and 25-hydroxy-vitamin D were collected. Bone mineral density was evaluated using dual-energy X-ray absorptiometry. Results. Compared to the Control group, calcium and vitamin D intake was lower in the Cases group (p = 0.03). Cases had higher Body Mass Index than Controls, p = 0.01. Children in the Cases group had lower mean serum calcium values 8.3 ± 1.4 compared to 9.3 ± 1.1 in Controls (p = 0.01). Alkaline phosphatase was higher in Cases 265 ± 65.8 than Controls 226 ± 54.6 (p = 0.03). Vitamin D and bone mineral density scores were significantly lower in the Cases group (p < 0.05). Conclusion. Our data shows an increased rate of vitamin D deficiency and decreased bone mineral density in Egyptian children with forearm fractures. PMID:27651803

  2. Probiotic Beverage with Soy Isoflavone Consumption for Breast Cancer Prevention: A Case-control Study.

    PubMed

    Toi, Masakazu; Hirota, Saya; Tomotaki, Ai; Sato, Nobuaki; Hozumi, Yasuo; Anan, Keisei; Nagashima, Takeshi; Tokuda, Yutaka; Masuda, Norikazu; Ohsumi, Shozo; Ohno, Shinji; Takahashi, Masato; Hayashi, Hironori; Yamamoto, Seiichiro; Ohashi, Yasuo

    2013-08-01

    The purpose of this study is to evaluate how beverages containing Lactobacillus casei Shirota (BLS) and soy isoflavone consumption since adolescence affected the incidence of breast cancer. In a population-based case-control study, three hundred and six cases with breast cancer and 662 controls aged 40 to 55 were matched for age and residential area and included in the analyses. Diet, lifestyle and other breast cancer risk factors were investigated using the self-administered questionnaire and interview. Odds ratios (ORs) of BLS and soy isoflavone consumption for breast cancer incidence were independently and jointly estimated using a conditional logistic regression. The ORs of BLS consumption (≥ four times a week against < four times a week) was 0.65 and statistically significant (p = 0.048). The analysis of association between soy consumption and breast cancer incidence showed the more the isoflavone consumption is, the lower the odds of breast cancer becomes. Adjusted ORs for breast cancer in the second, the third and the fourth quartiles of soy consumption against the first quartile were 0.76, 0.53 and 0.48, respectively (trend test, p = 0.0002). The BLS-isoflavone interaction was not statistically significant; however, a biological interaction was suggested. Regular consumption of BLS and isoflavones since adolescence was inversely associated with the incidence of breast cancer in Japanese women.

  3. Antiviral immunity following smallpox virus infection: a case-control study.

    PubMed

    Hammarlund, Erika; Lewis, Matthew W; Hanifin, Jon M; Mori, Motomi; Koudelka, Caroline W; Slifka, Mark K

    2010-12-01

    Outbreaks of smallpox (i.e., caused by variola virus) resulted in up to 30% mortality, but those who survived smallpox infection were regarded as immune for life. Early studies described the levels of neutralizing antibodies induced after infection, but smallpox was eradicated before contemporary methods for quantifying T-cell memory were developed. To better understand the levels and duration of immunity after smallpox infection, we performed a case-control study comparing antiviral CD4(+) and CD8(+) T-cell responses and neutralizing antibody levels of 24 smallpox survivors with the antiviral immunity observed in 60 smallpox-vaccinated (i.e., vaccinia virus-immune) control subjects. We found that the duration of immunity following smallpox infection was remarkably similar to that observed after smallpox vaccination, with antiviral T-cell responses that declined slowly over time and antiviral antibody responses that remained stable for decades after recovery from infection. These results indicate that severe, potentially life-threatening disease is not required for the development of sustainable long-term immunity. This study shows that the levels of immunity induced following smallpox vaccination are comparable in magnitude to that achieved through natural variola virus infection, and this may explain the notable success of vaccination in eradicating smallpox, one of the world's most lethal diseases.

  4. Lung cancer risk and welding--preliminary results from an ongoing case-control study.

    PubMed

    Jöckel, K H; Ahrens, W; Bolm-Audorff, U

    1994-06-01

    In a hospital-based case-control study, 391 male cases or primary lung cancer and the same number of controls--matched by sex, age, and region--were personally interviewed for their job and smoking histories. The data reported reflect the midpoint of a study aiming at a total of 1,000 cases. One objective of the study was to assess confounding by asbestos exposure in what was thought to be a welding-associated risk. While the odds ratios (OR) increased steeply with cumulative exposure to tobacco smoke and were raised also for lifelong asbestos exposure of over 4,100 working hours (OR = 1.91), the effect of welding exposure was reduced after adjustment for smoking and exposure to asbestos. Furthermore, no consistent dose-response relationship could be shown in relation to welding hours. Therefore the present study supports the hypothesis that some, if not all, of the excess risk of welders observed in the literature may be due to the exposure to asbestos. The finding that the subgroup of employees in the aircraft industry showed an increased odds ratio of 2.14 after adjustment for smoking and exposure to asbestos deserves further attention. This suggests the need for further research on the role of berryllium-containing alloys, which has been suggested by other authors.

  5. 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.

  6. Antidepressants and Gastric Cancer: A Nationwide Population-Based Nested Case-Control Study

    PubMed Central

    Lin, Chiao-Fan; Chan, Hsiang-Lin; Liang, Hsin-Yi; Lee, Yena; McIntyre, Roger S.; Chen, Vincent Chin-Hung

    2015-01-01

    Background To our knowledge, no epidemiological study has reported on whether an association between antidepressant exposure and gastric cancer exists. Herein, we aim to investigate the possible association between antidepressant exposure and gastric cancer incidence. Methods Using a nested case-control design, we identified 26289 cases with gastric cancer and 127984 controls from Taiwan’s National Health Insurance Research Database (NHIRD). The data were analyzed using a conditional logistic regression model adjusting for possible confounding variables. Results We found antidepressant use did not increase the risk of gastric cancer. The lack of an association between antidepressant prescription and elevated gastric cancer incidence was apparent for across selective serotonin-reuptake inhibitors (SSRIs), tricyclic agents (TCAs), serotonin-norepinephrine reuptake inhibitors (SNRIs), reversible inhibitors of monoamine oxidase A (RIMA), trazodone, mirtazapine and bupropion. There were slightly decreased gastric cancer risks of SSRIs use (≧28 DDD group, adjusted OR = 0.87; 95% CI = 0.78–0.96). Sensitive analysis showed SSRIs, TCAs, and SNRIs did not increase gastric cancer risks significantly even in the group with peptic ulcer history. Conclusions An association between antidepressant exposure and gastric cancer was not apparent in this analysis. PMID:26606417

  7. Occupation and five cancers: a case-control study using death certificates.

    PubMed Central

    Magnani, C; Coggon, D; Osmond, C; Acheson, E D

    1987-01-01

    A case-control approach has been used to examine mortality from five cancers--oesophagus, pancreas, cutaneous melanoma, kidney, and brain--among young and middle aged men resident in three English counties. The areas studied were chosen because they include major centres of chemical manufacture. By combining data from 20 years it was possible to look at local industries with greater statistical power than is possible using routine national statistics. Each case was matched with up to four controls of similar age who died in the same year from other causes. The occupations and industries recorded on death certificates were coded to standard classifications and risk estimates derived for each job category. Where positive associations were found the records of the cases concerned were examined in greater detail to see whether the risk was limited to specific combinations of occupation and industry. The most interesting findings to emerge were risks of brain cancer associated with the production of meat and fish products (relative risk (RR) = 9.7, 95% confidence interval (CI) 2.6-36.8) and with mineral oil refining (RR = 2.9, CI 1.2-7.0), and a cluster of four deaths from melanoma among refinery workers (RR = 16.0, CI CI 1.8-143.2). A job-exposure matrix was applied to the data but gave no strong indications of further disease associations. Local analyses of occupational mortality such as this can usefully supplement national statistics. PMID:3689708

  8. Familial, Social and Environmental Risk Factors in Autism: A Case-Control Study.

    PubMed

    Jahan, A; Rezina-Parvin, S Z; Bugum, D

    2014-12-01

    This case-control study was done to identify the correlation between the familial, social and environmental risk factors and autism. This hospital and specialized centre based study done from January 2002 to November, 2004. Thirty two children from the autism group and 14 children from the control group were enrolled. Mean age were 3.75 yrs. and 2.83 yrs. respectively. Significant proportion of children were in the highest birth orders, 68.8% in autism and 78.6% in the control group. Full-term children were 96.9% and 92.9% respectively. 53.1% children in the autism and 57.1% in the normal speech delay group were born by cesarean sections. Higher education of parents in autism group was statistically significant (p < 0.05). Too much watching TV, inadequate opportunity to mix with peers and inadequate interactive relationship with the family members in the early childhood were significantly (p = 0.001) related to the development of autism. PMID:26402976

  9. 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

  10. Occupational risk factors for cancer of the pancreas: a case-control study.

    PubMed Central

    Pietri, F; Clavel, F; Auquier, A; Flamant, R

    1990-01-01

    The role of the occupational environment in the occurrence of cancer of the pancreas was analysed in a case-control study of 171 cases of pancreatic cancer and 317 controls matched for age at interview, sex, hospital, and interviewer. The study was conducted in France between 1982 and 1985 and covered 15 important industries and various other occupations. The results are given for the whole population, a subgroup of manual workers (46 cases and 108 controls), and a subgroup of French nationals (114 cases and 253 controls). After adjustment for cigarette smoking, and coffee and alcohol consumption, workers in the food industry (OR = 1.86) and the leather industry (OR = 1.63) showed higher risks than other industries. In the sub-group of French nationals only the risk associated with the textile industry was significantly higher than unity (OR = 2.30). No significant increase in risk was associated with work in any of the other branches studied; printing showed a moderate increase in risk (OR = 1.54). The subgroup of manual workers showed an increase in risk for cancer of the pancreas among those working in the building materials and building trades classification (OR = 2.16) and transportation (OR = 1.57). PMID:2378821

  11. 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. PMID:7272236

  12. Association of selenoprotein S gene polymorphism with ischemic stroke in a Chinese case-control study.

    PubMed

    Li, Xiao-Xia; Guan, Hong-Jun; Liu, Jian-Ping; Guo, Yu-Peng; Yang, Yong; Niu, Ying-Ying; Yao, Li-Yan; Yang, Yin-Dong; Yue, Hong-Yu; Meng, Li-Li; Cui, Xin-Yu; Yang, Xiao-Wei; Gao, Jin-Xiao

    2015-03-01

    Previous studies showed that selenoprotein S (SELS) was associated with a range of inflammatory markers, and its gene expression was influenced by a polymorphism in the promoter region. The genetic basis of the ischemic stroke has now been largely determined, so the aim of the study was to examine the role of SELS genetic variants in the ischemic stroke risk in a Chinese population. We conducted a case-control study with 239 ischemic stroke patients and 240 controls. Two single-nucleotide polymorphisms (SNPs) in SELS genes were analyzed for association with the risk of ischemic stroke in the Chinese Han population. No evidence of ischemic stroke association was observed with the SNP rs34713741. Interestingly, the strongest evidence showed that SELS SNP rs4965814 was associated with ischemic stroke (P < 0.05). We found a significant association with increased ischemic stroke risk in women carrying the CC genotype of rs4965814 [hazard ratio: 2.43(1.03-5.75)]; a similar trend was also found in men carrying the TC genotype of rs4965814 [hazard ratio: 1.81(1.06-3.08)]. SNP rs4965814 of SELS may affect the susceptibility to ischemic stroke. Understanding the inflammatory mechanisms of ischemic stroke may give new therapeutic targets to pharmacologists. PMID:25390504

  13. Environmental exposure to tremolite and respiratory cancer in New Caledonia: a case-control study.

    PubMed

    Luce, D; Bugel, I; Goldberg, P; Goldberg, M; Salomon, C; Billon-Galland, M A; Nicolau, J; Quénel, P; Fevotte, J; Brochard, P

    2000-02-01

    A case-control study on respiratory cancers was conducted in New Caledonia (South Pacific), where a high incidence of malignant pleural mesothelioma had been observed. The disease pattern suggested an environmental exposure to asbestos. The first results showed that, in some areas, tremolite asbestos derived from local outcroppings was used as whitewash (locally named "pö"). All cases diagnosed between 1993 and 1995 (including 15 pleural mesotheliomas, 228 lung cancers, and 23 laryngeal cancers) and 305 controls were included in the study. Detailed information on past or present use of the whitewash, residential history, smoking, diet, and occupation was collected. The risk of mesothelioma was strongly associated with the use of the whitewash (odds ratio (OR) = 40.9; 95% confidence interval (CI): 5.15, 325). All Melanesian cases had been exposed. Among Melanesian women, exposure to the whitewash was associated with an increased risk of lung cancer (OR = 4.89; 95% CI: 1.13, 21.2), and smokers exposed to po had an approximately ninefold risk (OR = 9.26; 95% CI: 1.72, 49.7) compared with women who never smoked and had never used the whitewash. In contrast, no association was noted between exposure to pö and lung cancer risk among Melanesian men, probably because of lower exposure levels. Among non-Melanesians, the numbers of exposed subjects were too small to assess the effect of exposure to po. There was no indication of elevated risks for the other cancer sites.

  14. Varenicline and Risk of Self-Harm: A Nested Case-Control Study

    PubMed Central

    Martins, Diana; Yao, Zhan; Mamdani, Muhammad M.; Juurlink, David N.; Gomes, Tara; Antoniou, Tony

    2016-01-01

    Background Smoking remains a serious public health concern. Pharmacotherapy for smoking cessation, including bupropion and varenicline, are proven means to increase quit rates. Post-marketing reports describing suicidal behaviours have raised concerns about the safety of varenicline. However, whether varenicline imparts a higher risk of suicide relative to bupropion remains uncertain. Methods A population-based nested case-control study in Ontario, Canada, from April 1, 2011 to March 31, 2015 was conducted. Subjects were residents of Ontario aged 18 years and older with publicly funded drug coverage receiving either bupropion or varenicline for smoking cessation. We defined cases were those with a hospitalization or emergency department visit for suicide or non-fatal self-harm within 90 days of treatment. For each case, we identified up to fifty controls from the same cohort matched on age, sex, history of self-harm, use of selected psychotropic medications, alcohol abuse and prior admission to a mental health unit. Adjusted odds ratio were used to compare the risk of suicide/self-harm of varenicline to bupropion. Results We identified 331 cases and 5,346 matched-controls. Following adjustment for potential confounders, we found that varenicline was not associated with an increased risk of suicide/self-harm relative to bupropion (adjusted odds ratio 1.15; 95% confidence interval 0.71 to 1.87). Interpretation Treatment with varenicline does not appear to significantly increase the risk of suicide or self-harm relative to bupropion. PMID:27662654

  15. Prevalence of Cytomegalovirus in Patients With Multiple Sclerosis: A Case-Control Study in Northern Iran

    PubMed Central

    Najafi, Saeideh; Ghane, Masood; Poortahmasebi, Vahdat; Jazayeri, Seyed Mohammad; Yousefzadeh-Chabok, Shahrokh

    2016-01-01

    Background Multiple sclerosis (MS) is a chronic debilitating disease known as one of the most common neurological dysfunctions in young adults. Recent studies suggest that infections with herpesviruses play a critical role in the pathogenesis of MS. Objectives The present investigation aimed to detect the presence of cytomegalovirus (CMV) in patients with MS using polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay (ELISA) methods. Patients and Methods Plasma and peripheral blood mononuclear cells (PBMCs) were collected from MS patients (n = 82) and from blood donors as control group (n = 89). They were tested for the presence of CMV antibodies and DNA by ELISA and PCR, respectively. Results Anti-CMV was positive in 65 (79.3%) and 69 (77.5%) of the MS patients and healthy subjects, respectively (P= 0.853). Similarly, 23 (28%) and 2 (2.2%) patients were positive for CMV DNA among the MS and control groups, respectively. Statistical analysis showed that the frequency of CMV DNA in the MS patients was significantly higher than in the healthy controls (P < 0.001). Conclusions The results of this study showed a possible association between CMV infection and MS. Further experimental and epidemiological studies using case-control approaches are needed to confirm this association. PMID:27679707

  16. A stepwise likelihood ratio test procedure for rare variant selection in case-control studies.

    PubMed

    Kuk, Anthony Y C; Nott, David J; Yang, Yaning

    2014-04-01

    There is much recent interest in finding rare genetic variants associated with various diseases. Owing to the scarcity of rare mutations, single-variant analyses often lack power. To enable pooling of information across variants, we use a random effect formulation within a retrospective modeling framework that respects the retrospective data collecting mechanism of case-control studies. More concretely, we model the control allele frequencies of the variants as random effects, and the systematic differences between the case and control frequencies as fixed effects, resulting in a mixed model. The use of Poisson approximation and gamma-distributed random effects results in a generalized negative binomial distribution for the joint distribution of the control and case frequencies. Variants are selected by conducting stepwise likelihood ratio tests. The superiority of the proposed method over two existing variant selection methods is demonstrated in a simulation study. The effects of non-gamma random effects and correlated variants are also found to be not too detrimental in the simulation study. When the proposed procedure is applied to identify rare variants associated with obesity, it identifies one additional variant not picked up by existing methods. PMID:24451226

  17. Risk factors for esophageal and gastric cancers in Shanxi Province, China: A case-control study

    PubMed Central

    GAO, Ying; HU, Nan; HAN, Xiao You; DING, Ti; GIFFEN, Carol; GOLDSTEIN, Alisa M; TAYLOR, Philip R

    2011-01-01

    Objective Smoking and alcohol consumption explain little of the risk for upper-gastrointestinal (UGI) cancer in China, where over half of all cases in the world occur. Methods We evaluated questionnaire-based risk factors for UGI cancers in a case-control study from Shanxi Province, China, including 600 esophageal squamous cell carcinomas (ESCC), 599 gastric cardia adenocarcinomas (GCA), 316 gastric noncardia adenocarcinomas (GNCA), and 1514 age- and gender-matched controls. Results Ever smoking and ever use of any alcohol were not associated with risk of UGI cancer; only modest associations were observed between ESCC risk and highest cumulative smoking exposure, as well as GNCA risk and beer drinking. While several associations were noted for socioeconomic and some dietary variables with one or two UGI cancers, the strongest and most consistent relations for all three individual UGI cancers were observed for consumption of scalding hot foods (risk increased 150% to 219% for daily vs never users) and fresh vegetables and fruits (risk decreased 48% to 70% for vegetables and 46% to 68% for fruits, respectively, for high vs low quartiles). Conclusion This study confirms the minor role of tobacco and alcohol in UGI cancers in this region, and highlights thermal damage as a leading etiologic factor. PMID:21846596

  18. Level of neurotoxic metals in amyotrophic lateral sclerosis: A population-based case-control study.

    PubMed

    Bocca, Beatrice; Forte, Giovanni; Oggiano, Riccardo; Clemente, Simonetta; Asara, Yolande; Peruzzu, Angela; Farace, Cristiano; Pala, Salvatore; Fois, Alessandro Giuseppe; Pirina, Pietro; Madeddu, Roberto

    2015-12-15

    The association between exposure to toxic metals and amyotrophic lateral sclerosis (ALS) was explored in a population-based case-control study in the Sardinia island (Italy), a region characterized by elevated rates of ALS cases. In 34 patients with ALS (mean age, 62 ± 10 years) and 30 controls (mean age, 65 ± 11 years), Al, Cd, Hg, Mn and Pb were determined in blood, hair and urine by sector field inductively coupled mass spectrometry. Results indicated that, in blood, concentrations of Al (p=0.045) and Pb were higher (p=0.026) in ALS patients than in control subjects. In hair, a depletion of Al (p=0.006) and Mn (p=0.032) concentrations in ALS subjects respect to controls was found. In urine, no significant differences between cases and controls were observed. Thus, some metals seemed to be associated with ALS degeneration, but a definitive conclusion is still far considering the multiple risk factors (genetic mutations, environmental toxicants and stressors) involved in the disease. Finally, the interpretation that deregulated metal concentrations can be a consequence of the degenerative process, rather than a cause, is also valid. PMID:26671079

  19. Lung cancer among glass fibre production workers: a case-control study.

    PubMed Central

    Gardner, M J; Magnani, C; Pannett, B; Fletcher, A C; Winter, P D

    1988-01-01

    A cohort study among 4734 employees at an English glass fibre plant previously reported no excess of lung cancer mortality either overall or when examined in broad occupational groups. To investigate occupation in more detail, and to test the hypothesis that processes producing or using finer (respirable) fibres may be related to a higher risk of lung cancer, a nested case-control study has now been carried out. Included are 73 cases of lung cancer and 506 matched controls, for whom jobs held and processes worked on have been blindly recorded in more detail than for the cohort study. Workers known to have been employed on processes containing respirable fibres had a relative risk of lung cancer of 1.2 (95% confidence interval 0.7-2.0) compared with other workers. There was no evidence of a relationship of lung cancer to fibre diameter, duration of exposure, or time since first exposure. The results by broad occupational group were similar to those of the cohort study, and although some of the many detailed occupational categories examined had significantly raised relative risks, these did not appear to be related to exposure to respirable glass fibre. Although the study has not indicated a differential risk of lung cancer among workers exposed to finer diameter glass fibres, the exposure levels were low and the number of cases small. PMID:3179236

  20. A Nested Case-Control Study of Association between Metabolome and Hypertension Risk.

    PubMed

    Hao, Yongchen; Wang, Ying; Xi, Lu; Li, Guoqi; Zhao, Fan; Qi, Yue; Liu, Jing; Zhao, Dong

    2016-01-01

    We aimed to explore novel small metabolites that associated with hypertension risk in a population-based nested case-control study. Among 460 individuals with optimal blood pressure (<120/80 mmHg) at baseline, 55 progressed to hypertension during 5 years of follow-up. Twenty-nine cases of incident hypertension and 29 controls, matched for age, sex, and baseline systolic blood pressure, were included in this study. Serum metabolites were measured by gas chromatography-tandem mass spectrometry. t-test and logistic regression analysis were applied to investigate the association between metabolites and incident hypertension. Among the 241 metabolites identified in this study, baseline levels of 26 metabolites were significantly different between hypertension and control groups. After adjusting for body mass index, smoking, and drinking, 16 out of the 26 metabolites were still associated with hypertension risk including four amino acids. Amino acids were negatively associated with risk of future hypertension, with odds ratio (OR) ranging from 0.33 to 0.53. Two of these amino acids were essential amino acids including threonine and phenylalanine. Higher level of lyxose, a fermentation product of gut microbes, was associated with higher risk of hypertension. Our study identified multiple metabolites that associated with hypertension risk. These findings implied that low amino acid levels and gut microbiome might play an important role in the pathogenesis of hypertension. PMID:27119083

  1. Factors associated with syphilis infection: a comprehensive analysis based on a case-control study.

    PubMed

    Xiao, Y; Li, S-L; Lin, H-L; Lin, Z-F; Zhu, X-Z; Fan, J-Y; Gao, K; Zhang, H-L; Lin, L-R; Liu, L-L; Tong, M-L; Niu, J-J; Yang, T-C

    2016-04-01

    This study aimed to comprehensively evaluate factors that influence the likelihood of syphilis infection from risk-taking behaviours and medical conditions. A retrospective case-control study was conducted by enrolling 664 syphilis inpatients (excluding 11 congenital syphilis patients) and 800 sex- and age-matched controls. Medical histories, clinical data and patient interview data were collected and subjected to logistic regression analyses. The prevalence of syphilis in the study population was 3·9% (675/17,304). By univariate analysis, syphilis infection was associated with migration between cities, marital status, smoking, reproductive history, hypertension, elevated blood urea nitrogen (BUN) and infection with hepatitis B virus (HBV) (P < 0·05). A high rate of syphilis-HBV co-infection was observed in HIV-negative patients and further research revealed an association between syphilis and specific HBV serological reactivity. Syphilis was also associated with the frequency, duration and status of tobacco use. Multivariate analysis indicated that syphilis infection was independently associated with migration between cities [adjusted odds ratio (aOR) 1·368, 95% confidence interval (CI) 1·048-1·785], current smoking (aOR 1·607, 95% CI 1·177-2·195), elevated BUN (aOR 1·782, 95% CI 1·188-2·673) and some serological patterns of HBV infection. To prevent the spread of infectious diseases, inpatients and blood donors should be tested for HIV, syphilis, HBV and HCV simultaneously.

  2. HLA-DR and -DQ eplet mismatches and transplant glomerulopathy: a nested case-control study.

    PubMed

    Sapir-Pichhadze, R; Tinckam, K; Quach, K; Logan, A G; Laupacis, A; John, R; Beyene, J; Kim, S J

    2015-01-01

    We conducted a nested case-control study from a cohort of adult kidney transplant recipients to assess the risk of transplant glomerulopathy (TG) as a function of donor and recipient HLA-DR and -DQ incompatibility at the eplet level. Cases (n = 52) were defined as patients diagnosed with transplant glomerulopathy based on biopsies showing glomerular basement membrane duplication without immune complex deposition. Controls (n = 104) with a similar follow-up from transplantation were randomly selected from the remaining cohort. HLAMatchmaker was used to ascertain the number of DRB1/3/4/5, DQA1 and DQB1 related eplet mismatches (eplet load). Multivariable conditional logistic regression models demonstrated an increase in the odds of TG (odds ratios [OR] of 2.84 [95% confidence interval (CI): 1.03, 7.84] and 4.62 [95% CI: 1.51, 14.14]) in the presence of 27-43 and >43 HLA-DR + DQ related eplet mismatches versus <27 eplet mismatches, respectively. When the eplet load was modeled as a continuous variable, the OR for TG was 1.25 (95% CI: 1.04, 1.50) for every 10 additional HLA-DR + DQ eplet mismatches. Our study suggests that minimization of HLA-DR + DQ eplet mismatches may decrease the incidence of transplant glomerulopathy diagnosed by indication biopsies. The role of eplet immunogenicity/antigenicity as determinants of allograft outcomes requires further study. PMID:25521856

  3. Chronic beryllium disease and beryllium sensitization at Rocky Flats: a case-control study.

    PubMed

    Viet, S M; Torma-Krajewski, J; Rogers, J

    2000-01-01

    A case-control study was conducted to evaluate the risk of chronic beryllium disease (CBD) and beryllium sensitization (SENS) associated with various levels of historical beryllium exposure at the Rocky Flats nuclear weapons facility. Fifty CBD and 74 SENS cases were matched to controls of the same age group, race, gender, and smoking status. A job exposure matrix was developed from job history data and fixed airhead (FAH) exposure data available from 1960 to 1988. Job titles and building areas were assigned factors based on exposure relative to a machinist in the Building 444 Beryllium Shop. Concurrence on these factors was obtained from past and present Rocky Flats industrial hygienists. Using the matrix, long-term mean and cumulative exposures were estimated for each subject. Both exposure estimates (p < 0.0001) and years of employment (p = 0.010) were found to be significantly higher for CBD cases as compared with their controls, but not so for the SENS cases as compared with their controls. Logistic regression analyses showed statistically significant relationships between both cumulative and mean exposure and CBD, but not for SENS. These findings suggest that reduced worker exposures might lower the future incidence of CBD, but may not necessarily lower the incidence of SENS. PMID:10782196

  4. A case-control study of risk factors for bovine brucellosis seropositivity in Peninsular Malaysia.

    PubMed

    Anka, Mukhtar Salihu; Hassan, Latiffah; Khairani-Bejo, Siti; Zainal, Mohamed Abidin; Mohamad, Ramlan Bin; Salleh, Annas; Adzhar, Azri

    2014-01-01

    Bovine brucellosis was first reported in Peninsular Malaysia in 1950. A subsequent survey conducted in the country revealed that the disease was widespread. Current knowledge on the potential risk factors for brucellosis occurrence on cattle farms in Malaysia is lacking. Therefore, we conducted a case-control study to identify the potential herd-level risk factors for bovine brucellosis occurrence in four states in the country, namely Kelantan, Pahang, Selangor and Negeri Sembilan. Thirty-five cases and 36 controls of herds were selected where data on farm management, biosecurity, medical history and public health were collected. Multivariable logistic regression identified that Brucella seropositive herds were more likely to; have some interaction with wildlife (OR 8.9, 95% CI = 1.59-50.05); originated from farms where multiple species such as buffalo/others (OR 41.8, 95% CI = 3.94-443.19) and goat/sheep (OR 8.9, 95%Cl = 1.10-71.83) were reared, practice extensive production system (OR 13.6, 95% CI 1.31-140.24) and have had episodes of abortion in the past (OR 51.8, 95% CI = 4.54-590.90) when compared to seronegative herds. Considering the lack of information on the epidemiology of bovine brucellosis in peninsular Malaysia and absence of information on preventing the inception or spread of the disease, this report could contribute to the on-going area-wise national brucellosis eradication program.

  5. Adipokines as Possible New Predictors of Cardiovascular Diseases: A Case Control Study

    PubMed Central

    Pala, Laura; Monami, Matteo; Ciani, Silvia; Dicembrini, Ilaria; Pasqua, Alessandro; Pezzatini, Anna; Francesconi, Paolo; Cresci, Barbara; Mannucci, Edoardo; Rotella, Carlo Maria

    2012-01-01

    Background and Aims. The secretion of several adipocytokines, such as adiponectin, retinol-binding protein 4 (RBP4), adipocyte fatty acid binding protein (aFABP), and visfatin, is altered in subjects with abdominal adiposity; these endocrine alterations could contribute to increased cardiovascular risk. The aim of the study was to assess the relationship among adiponectin, RBP4, aFABP, and visfatin, and incident cardiovascular disease. Methods and Results. A case-control study, nested within a prospective cohort, on 2945 subjects enrolled for a diabetes screening program was performed. We studied 18 patients with incident fatal or nonfatal IHD (Ischemic Heart Disease) or CVD (Cerebrovascular Disease), compared with 18 matched control subjects. Circulating adiponectin levels were significantly lower in cases of IHD with respect to controls. Circulating RBP4 levels were significantly increased in CVD and decreased in IHD with respect to controls. Circulating aFABP4 levels were significantly increased in CVD, while no difference was associated with IHD. Circulating visfatin levels were significantly lower in cases of both CVD and IHD with respect to controls, while no difference was associated with CVD. Conclusions. The present study confirms that low adiponectin is associated with increased incidents of IHD, but not CVD, and suggests, for the first time, a major effect of visfatin, aFABP, and RBP4 in the development of cardiovascular disease. PMID:21869928

  6. Evaluating Bone Health in Egyptian Children with Forearm Fractures: A Case Control Study

    PubMed Central

    Elbatrawy, Salwa; Gobashy, Amr; Moreira, Alvaro

    2016-01-01

    Objective. To determine the likelihood of vitamin D deficiency and low bone mineral density in Egyptian children with forearm fractures. Methods. A case control study of 46 children aged 3 to 10 years with or without forearm fractures. Validated questionnaires were used to assess calcium and vitamin D intake as well as sun exposure. Serum calcium, phosphorus, alkaline phosphatase, and 25-hydroxy-vitamin D were collected. Bone mineral density was evaluated using dual-energy X-ray absorptiometry. Results. Compared to the Control group, calcium and vitamin D intake was lower in the Cases group (p = 0.03). Cases had higher Body Mass Index than Controls, p = 0.01. Children in the Cases group had lower mean serum calcium values 8.3 ± 1.4 compared to 9.3 ± 1.1 in Controls (p = 0.01). Alkaline phosphatase was higher in Cases 265 ± 65.8 than Controls 226 ± 54.6 (p = 0.03). Vitamin D and bone mineral density scores were significantly lower in the Cases group (p < 0.05). Conclusion. Our data shows an increased rate of vitamin D deficiency and decreased bone mineral density in Egyptian children with forearm fractures.

  7. Dietary Intake and Serum Level of Carotenoids in Lung Cancer Patients: A Case-Control Study.

    PubMed

    Asbaghi, Somayeh; Saedisomeolia, Ahmad; Hosseini, Mostafa; Honarvar, Niyaz Mohammadzadeh; Khosravi, Adnan; Azargashb, Eznollah

    2015-01-01

    The aim of this study was to compare the dietary intake and serum levels of some selected carotenoids of lung cancer patients with healthy subjects. Thirty-five lung cancer patients and 33 healthy people were enrolled into this case-control study. Daily intake of nutrients was estimated using a semiquantitative food frequency questionnaire and a 3-day 24-h food recall questionnaire. The concentration of serum beta-carotene and lycopene were analyzed using a high performance liquid chromatography method. Case and control groups did not differ by the means of age, gender, smoking habits, weight, body mass index, mean daily energy intake, mean daily fat intake, and the percentage of daily energy provided by fat to total daily energy intake. The beta-carotene and lycopene intake of the case subjects was 96% and 195% greater than that of the control subjects. Daily intake of fruits and vegetables in the cancer group was higher than the control group. However, the serum concentration of 118% beta-carotene and 60% lycopene were higher in the control group. Despite a higher daily dietary intake of beta-carotene and lycopene by lung cancer patients, serum beta-carotene and lycopene concentrations were significantly lower than the group without cancer.

  8. Association between chronic periodontitis and rheumatoid arthritis: a hospital-based case-control study.

    PubMed

    Joseph, Rosamma; Rajappan, Sreeraj; Nath, Sameera G; Paul, Binoy J

    2013-01-01

    Rheumatoid arthritis (RA) and chronic periodontitis are the most common chronic inflammatory diseases with remarkable pathological and clinical similarities. A lot of similarities exist between RA and periodontitis at cellular and molecular levels. The relationship between these two chronic inflammatory diseases is still unclear. This case-control study was undertaken to determine the possible association between chronic inflammatory diseases like RA and periodontitis. The case group consisted of 100 patients attending the Rheumatology clinic who have rheumatoid arthritis (RA group). Age- and gender-matched 112 patients without RA attending the Outpatient wing of Department of General Medicine formed the control group (NRA group). The number of missing teeth, gingival index (GI), oral hygiene index-simplified (OHI-S), probing pocket depth (PPD) and clinical attachment levels (CAL) were evaluated in both the groups. Rheumatoid disease activity was assessed by DAS-28 score system. Systemic markers of inflammation like erythrocytic sedimentation rate (ESR) and serum levels of C-reactive protein (CRP) were assessed. There was a statistically significant difference in GI, OHI-S, PPD, CAL, ESR and CRP levels between cases (RA group) and controls (NRA group) (P < 0.05). Among subjects with RA, there was no association between the rheumatoid disease activity and the severity of periodontal disease. The occurrence and severity of periodontitis was found to be higher in RA subjects as compared to subjects without RA, suggesting a positive relation between these two chronic inflammatory diseases. PMID:22228465

  9. Melanoma and occupation: results of a case-control study in The Netherlands.

    PubMed

    Nelemans, P J; Scholte, R; Groenendal, H; Kiemeney, L A; Rampen, F H; Ruiter, D J; Verbeek, A L

    1993-07-01

    Several studies have reported excesses of risk of melanoma in specific industries. Data from a case-control study in The Netherlands, including 140 cases with a cutaneous melanoma and 181 controls with other types of malignancy, were used to evaluate whether the reported associations with these specific industries could be reproduced. Adjustment for characteristics of pigmentation and exposure to sunlight was made. Increased risks of cutaneous melanoma were found for subjects who had ever worked in the electronics industry (odds ratio (OR) = 2.03, 95% confidence interval (95% CI) 0.63-6.62), in the metal industry (OR = 2.61, 95% CI 0.96-7.10), and in the transport and communication branch (OR = 1.92, 95% CI 0.84-4.35). These ORs were adjusted for age, sex, education, hair colour, tendency to burn, freckling, and exposure to sunlight. No increased risks were seen for workers in the chemical industry, the textile industry, and among health care workers. Analyses according to duration and latency of exposure did not give consistent results, but existing patterns may be obscured by the imprecision of the estimates. PMID:8343426

  10. A Shrinkage Method for Testing the Hardy-Weinberg Equilibrium in Case-Control Studies

    PubMed Central

    Zang, Yong; Yuan, Ying

    2014-01-01

    Testing for the Hardy-Weinberg equilibrium (HWE) is often used as an initial step for checking the quality of genotyping. When testing the HWE for case-control data, the impact of a potential genetic association between the marker and the disease must be controlled for otherwise the results may be biased. Li and Li (2008) proposed a likelihood ratio test (LRT) that accounts for this potential genetic association and it is more powerful than the commonly used control-only χ2 test. However, the LRT is not efficient when the marker is independent of the disease, and also requires numerical optimization to calculate the test statistic. In this article, we propose a novel shrinkage test for assessing the HWE. The proposed shrinkage test yields higher statistical power than the LRT when the marker is independent of or weakly associated with the disease, and converges to the LRT when the marker is strongly associated with the disease. In addition, the proposed shrinkage test has a closed form and can be easily used to test the HWE for large datasets that result from genome-wide association studies. We compare the performance of the shrinkage test with existing methods using simulation studies, and apply the shrinkage test to a genome-wide association dataset for Alzheimer’s disease. PMID:23934751

  11. Preventing birth defects: The value of the NBDPS case-control approach.

    PubMed

    Dolk, Helen

    2015-08-01

    Birth Defect Registries provide a basis for epidemiological research into risk factors, thus facilitating a growing understanding of what causes congenital anomalies and how one might target preventive public health actions and reduce inequalities. The National Birth Defects Prevention Study (NBDPS) has used 10 U.S. registries as a basis for a large case-control study. This commentary reviews its methodology and selected areas of output. The strengths of NBDPS lie in the quality of diagnostic coding and classification of birth defects and its size. The sources of bias in NBDPS data relate particularly to retrospective exposure ascertainment entailing a long period of recall, incomplete ascertainment of terminations of pregnancy for fetal anomaly, and unknown bias in case selection. NBDPS results have shown the protective effect of healthy dietary patterns, but have not been as informative as expected in relation to furthering understanding of the protective effect of folic acid. NBDPS medication studies are making important contributions to addressing the gap in existing evidence systematically across a wide range of birth defects, but are challenged by the quality of information on exposure, dose and underlying disease condition, and the interpretation of results of multiple testing. Studies of environmental contaminants in collaboration with experts in exposure assessment have linked addresses to residential exposure measures, using the advantages of information on residential history and confounders, but are challenged by the need to consider exposure mixtures. NBDPS could increase its public health impact by placing more emphasis on socioeconomic inequalities.

  12. Soft tissue sarcoma and military service in Vietnam: a case-control study

    SciTech Connect

    Kang, H.; Enziger, F.; Breslin, P.; Feil, M.; Lee, Y.; Shepard, B.

    1987-10-01

    A case-control study was conducted in men who were of draftable age during the Vietnam conflict to examine the association of soft tissue sarcomas (STSs) with military service in Vietnam as well as other host and environmental risk factors. A total of 217 STS cases selected from the Armed Forces Institute of Pathology were compared to 599 controls for Vietnam service, occupational and nonoccupational exposure to various chemicals, occupational history, medical history, and life-style (smoking, alcohol, coffee, etc.). Military service information was verified by a review of the patient's military personnel records. Other information was ascertained from a telephone interview with either subjects or their next of kin. Cases and controls were stratified on the basis of the hospital type (civilian, Veterans Administration, and military); the Mantel-Haenszel estimate of the odds ratio (OR), adjusted for the effects of the stratification variable, was calculated. Vietnam veterans in general did not have an increased risk of STS when compared to those men who had never been in Vietnam (OR, 0.85; 95% confidence interval, 0.54-1.36). Subgroups of Vietnam veterans who had higher estimated opportunities for Agent Orange exposure seemed to be at greater risk of STSs when their counterparts in Vietnam were taken as a reference group. However, this risk was not statistically significant.

  13. A case-control study of mesothelioma and employment in the Hawaii sugarcane industry.

    PubMed

    Sinks, T; Goodman, M T; Kolonel, L N; Anderson, B

    1994-07-01

    We conducted a case-control study of 93 mesothelioma cases and 281 cancer controls to determine whether sugarcane workers exposed to biogenic silica fibers were at increased risk of mesothelioma. We found no important excess risk of mesothelioma in sugarcane workers [odds ratio (OR) = 1.3; 95% confidence interval (CI) = 0.4-3.8] when we excluded all control subjects with cancer of sites suspected of being associated with asbestos exposure. We could not identify any sugarcane workers who developed mesothelioma and worked in jobs where high exposure levels of biogenic silica fibers have been measured. We did confirm that mesothelioma risk in Hawaii is associated with probable occupational asbestos exposure. Work at the Pearl Harbor Naval Shipyard was associated with a 10-fold increase in mesothelioma when we excluded controls with cancer of sites related to asbestos exposure (OR = 10.1; 95% CI = 2.6-56.6). Work in the medical industry was also associated with an unexpected increased risk for mesothelioma (OR = 4.2; 95% CI = 1.2-15.5).

  14. Prevalence of Small Intestinal Bacterial Overgrowth among Chronic Pancreatitis Patients: A Case-Control Study.

    PubMed

    Therrien, Amelie; Bouchard, Simon; Sidani, Sacha; Bouin, Mickael

    2016-01-01

    Background. Patients with chronic pancreatitis (CP) exhibit numerous risk factors for the development of small intestinal bacterial overgrowth (SIBO). Objective. To determine the prevalence of SIBO in patients with CP. Methods. Prospective, single-centre case-control study conducted between January and September 2013. Inclusion criteria were age 18 to 75 years and clinical and radiological diagnosis of CP. Exclusion criteria included history of gastric, pancreatic, or intestinal surgery or significant clinical gastroparesis. SIBO was detected using a standard lactulose breath test (LBT). A healthy control group also underwent LBT. Results. Thirty-one patients and 40 controls were included. The patient group was significantly older (53.8 versus 38.7 years; P < 0.01). The proportion of positive LBTs was significantly higher in CP patients (38.7 versus 2.5%: P < 0.01). A trend toward a higher proportion of positive LBTs in women compared with men was observed (66.6 versus 27.3%; P = 0.056). The subgroups with positive and negative LBTs were comparable in demographic and clinical characteristics, use of opiates, pancreatic enzymes replacement therapy (PERT), and severity of symptoms. Conclusion. The prevalence of SIBO detected using LBT was high among patients with CP. There was no association between clinical features and the risk for SIBO. PMID:27446865

  15. Liver enzymes and metabolic syndrome: a large-scale case-control study.

    PubMed

    Zhang, Lu; Ma, Xiangyu; Jiang, Zhi; Zhang, Kejun; Zhang, Mengxuan; Li, Yafei; Zhao, Xiaolan; Xiong, Hongyan

    2015-09-29

    Previous studies suggested that elevated liver enzymes could be used as potential novel biomarkers of Metabolic syndrome (MetS) and its clinical outcomes, although the results were inconsistent and the conclusions were underpowered. A case-control study with 6,268 MetS subjects and 6,330 frequency-matched healthy controls was conducted to systematically evaluated levels of four liver enzymes (ALT, AST, GGT and ALP), both in overall populations and in subjects with normal liver enzymes, with MetS risk using both quartiles and continuous unit of liver enzymes. We found significant associations were detected for all above analyses. Compared with quartile 1 (Q1), other quartiles have significant higher MetS risk, with ORs ranging from 1.15 to 18.15. The highest effected was detected for GGT, for which the OR value for the highest versus lowest quartile was 18.15 (95% CI: 15.7-20.9). Mutual adjustment proved the independence of the relations for all four liver enzymes. Sensitivity analyses didn't materially changed the trend. To the best of our knowledge, this study should be the largest, which aimed at evaluating the association between liver enzymes measures and MetS risk. The results can better support that liver enzyme levels could be used as clinical predictors of MetS.

  16. Psychosocial Stress and Risk of Myocardial Infarction: A Case-Control Study in Belgrade (Serbia)

    PubMed Central

    Vujcic, Isidora; Vlajinac, Hristina; Dubljanin, Eleonora; Vasiljevic, Zorana; Matanovic, Dragana; Maksimovic, Jadranka; Sipetic, Sandra

    2016-01-01

    Background The purpose of this study was to investigate which psychosocial risk factors show the strongest association with occurrence of myocardial infarction (MI) in the population of Belgrade in peacetime, after the big political changes in Serbia. Methods A case-control study was conducted involving 154 consecutive newly diagnosed patients with MI, and 308 controls matched by gender, age, and place of residence. Results According to conditional logistic regression analysis, after adjustment for conventional coronary risk factors, the odds ratios (95% confidence intervals) for work-related stressful events, financial stress, deaths and diseases, and general stress were 3.78 (1.83-7.81), 3.80 (1.96-7.38), 1.69 (1.03-2.78), and 3.54 (2.01-6.22), respectively. Among individual stressful life events, the following were independently related to MI: death of a close family member, 2.21 (1.01-4.84); death of a close friend, 42.20 (3.70-481.29); major financial problems, 8.94 (1.83-43.63); minor financial problems, 4.74 (2.02-11.14); changes in working hours, 4.99 (1.64-15.22); and changes in working conditions, 30.94 (5.43-176.31). Conclusions During this political transition period , stress at work, financial stress, and stress in general as they impacted the population of Belgrade, Serbia were strongly associated with occurence of MI. PMID:27274168

  17. Dietary Intake and Serum Level of Carotenoids in Lung Cancer Patients: A Case-Control Study.

    PubMed

    Asbaghi, Somayeh; Saedisomeolia, Ahmad; Hosseini, Mostafa; Honarvar, Niyaz Mohammadzadeh; Khosravi, Adnan; Azargashb, Eznollah

    2015-01-01

    The aim of this study was to compare the dietary intake and serum levels of some selected carotenoids of lung cancer patients with healthy subjects. Thirty-five lung cancer patients and 33 healthy people were enrolled into this case-control study. Daily intake of nutrients was estimated using a semiquantitative food frequency questionnaire and a 3-day 24-h food recall questionnaire. The concentration of serum beta-carotene and lycopene were analyzed using a high performance liquid chromatography method. Case and control groups did not differ by the means of age, gender, smoking habits, weight, body mass index, mean daily energy intake, mean daily fat intake, and the percentage of daily energy provided by fat to total daily energy intake. The beta-carotene and lycopene intake of the case subjects was 96% and 195% greater than that of the control subjects. Daily intake of fruits and vegetables in the cancer group was higher than the control group. However, the serum concentration of 118% beta-carotene and 60% lycopene were higher in the control group. Despite a higher daily dietary intake of beta-carotene and lycopene by lung cancer patients, serum beta-carotene and lycopene concentrations were significantly lower than the group without cancer. PMID:26168284

  18. Oral and pharyngeal cancer and occupation: a case-control study.

    PubMed

    Huebner, W W; Schoenberg, J B; Kelsey, J L; Wilcox, H B; McLaughlin, J K; Greenberg, R S; Preston-Martin, S; Austin, D F; Stemhagen, A; Blot, W J

    1992-07-01

    We studied the relation between occupation and oral and pharyngeal cancer with a population-based case-control study conducted in four areas of the United States. The study group included 1,114 incident male and female cases and 1,268 frequency-matched controls. After adjustment for age, race, smoking, alcohol, and study location, an analysis of lifetime occupational histories revealed a small number of noteworthy associations. Risk was increased among male carpet installers (23 cases, 4 controls), with an adjusted odds ratio of 7.7 [95% confidence interval (CI) = 2.4-24.9], and tended to rise with longer duration of employment. A decreased risk was found among male and female textile mill workers (odds ratio 0.48, 95% CI = 0.27-0.88). Previously reported increases in oral cancer risks among printing workers, electrical and electronics workers, and workers other than carpet installers who were possibly exposed to formaldehyde were not found in this study. For several employment groups, including male machinists, primary metal industry workers, petroleum industry workers, painters, furniture and fixture industry workers, woodworking machine operators, and workers with inferred exposure to fossil fuel combustion, odds ratios were approximately 2.0 for cancers of pharyngeal sites.

  19. Case-control study of skin cancer in the rubber industry

    SciTech Connect

    Bourguet, C.C.

    1983-01-01

    A case-control study of non-melanoma skin cancer was conducted in two companies of the American rubber manufacturing industry. The study goal was to examine the association of basal and squamous cell carcinoma with seven raw materials: carbon black, dustless, extender, and lubricating oils, waxes, solvents, and the rubber stock itself. Study members were white males belonging to predefined cohorts of rubber workers. Cases were identified from hospital pathology department records. Each case was matched with four controls of the same company, and year of birth and hire (+/- one year). Company A provided 31 cases (22 squamous cell carcinoma cases) and 118 controls. Company B provided 55 cases (43 squamous cell cases) and 216 controls. Exposure was estimated using employee personnel records. In Company A, squamous cell carcinoma was associated with rubber stock, lubricating oils, and non-polycyclic chemicals. Ten years of moderate rubber stock exposure multiplied the existing relative risk by 2.96 (95% CL: 1.06-8.23). Exposure to non-polycyclic chemicals carried a relative risk of 5.5 (1.28-23.48). These chemicals are used as accelerators, antioxidants, and antiozonants. Disease was negatively associated with extender oil exposure. In Company B, jobs with heat exposure (milling, extruding, and curing) were associated with disease. Using a second control group, matched on year of birth, there was no convincing evidence that cases had longer employment duration than controls. This does not suggest an overall skin cancer risk among rubber workers.

  20. Cannabis use and cancer of the head and neck: Case-control study

    PubMed Central

    Aldington, Sarah; Harwood, Matire; Cox, Brian; Weatherall, Mark; Beckert, Lutz; Hansell, Anna; Pritchard, Alison; Robinson, Geoffrey; Beasley, Richard

    2008-01-01

    Objective To investigate whether cannabis smoking increases the risk of head and neck cancer. Design Case-control study. Subjects and Methods Cases of head and neck cancer ≤55 years identified from hospital databases and the Cancer Registry, and controls randomly selected from the electoral roll completed interviewer-administered questionnaires. Logistic regression was used to estimate the relative risk of head and neck cancer. Results There were 75 cases and 319 controls. An increased risk of cancer was found with increasing tobacco use, alcohol consumption, and decreased income but not increasing cannabis use. The highest tertile of cannabis use (>8.3 joint years) was associated with a nonsignificant increased risk of cancer (relative risk = 1.6, 95% confidence interval, 0.5-5.2) after adjustment for confounding variables. Conclusions Cannabis use did not increase the risk of head and neck cancer; however, because of the limited power and duration of use studied, a small or longer-term effect cannot be excluded. PMID:18312888

  1. Risk factors for preterm birth: a case-control study in rural area of western China

    PubMed Central

    Zhang, Xiaosong; Zhou, Min; Chen, Lijun; Hao, Bo; Zhao, Gengli

    2015-01-01

    Preterm birth is the leading cause of perinatal morbidity and mortality in China, the study is to learn risk factors for preterm birth in rural area of western China. A 1:1 case-control study in which cases included the pregnant women of preterm birth and controls included the matched pregnant women of normal deliver was conducted in 5 counties in western China. Data about the general situation, pregnancy history, reproductive health infection (RTI) symptoms, pregnancy complications, et al were obtained by using questionnaire. The results showed that the risk factors related to preterm birth were including: family income, mother’s age ≥ 35 years old, antennal visiting ≤ 4 times, low education level, preterm birth history, abnormal vaginal discharge, pregnancy complications. The logistic regression analysis showed that only 3 factors of preterm birth were left at the last step, which of antenatal visiting ≤ 4 times, PROM and placenta previa had significant difference. We show that family income, age, antennal visiting, low education level, preterm birth history, abnormal vaginal discharge, pregnancy complications are the risk factors of preterm birth. PMID:26064379

  2. Exposure to pistachio pesticides and stillbirth: a case-control study

    PubMed Central

    2016-01-01

    OBJECTIVES Stillbirth is an undesirable outcome of pregnancy. In light of the increasing use of pesticides and growing concerns about the possible health effects of agricultural pesticides, we investigated the effect of exposure to pistachio pesticides on stillbirth in pregnant mothers. METHODS This case-control study was conducted in Rafsanjan, Iran from 2011 to 2012. A total of 125 females who had a recent stillbirth were included as the case group, and 250 controls were selected from females who had a recent live birth. For each case, two controls with the nearest propensity score to the case were selected. Data were collected using a protocol developed by the researcher that involved interviewing respondents and reviewing their medical records. Conditional multivariate and univariate logistic regression analysis were performed and odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. RESULTS The ORs of stillbirth in mothers living in pistachio gardens and those who were exposed to sprayed pesticides, in comparison to the controls, were 14.1 (95% CI, 3.3 to 63.4) and 5.0 (95% CI, 1.2 to 28.6), respectively. No significant differences were found in stillbirth rates according to the distance between the mother’s residence and a pistachio garden or involvement in agricultural activities. CONCLUSIONS The results of our study showed that exposure to pistachio pesticides during pregnancy may increase the likelihood of stillbirth in mothers. PMID:27156346

  3. Diet Quality Scores and Risk of Nasopharyngeal Carcinoma in Chinese Adults: A Case-Control Study.

    PubMed

    Wang, Cheng; Lin, Xiao-Ling; Fan, Yu-Ying; Liu, Yuan-Ting; Zhang, Xing-Lan; Lu, Yun-Kai; Xu, Chun-Hua; Chen, Yu-Ming

    2016-03-01

    Many studies show that dietary factors may affect the risk of nasopharyngeal carcinoma (NPC). We examined the association between overall diet quality and NPC risk in a Chinese population. This case-control study included 600 NPC patients and 600 matched controls between 2009 and 2011 in Guangzhou, China. Habitual dietary intake and various covariates were assessed via face-to-face interviews. Diet quality scores were calculated according to the Healthy Eating Index-2005 (HEI-2005), the alternate Healthy Eating Index (aHEI), the Diet Quality Index-International (DQI-I), and the alternate Mediterranean Diet Score (aMed). After adjustment for various lifestyle and dietary factors, greater diet quality scores on the HEI-2005, aHEI, and DQI-I-but not on the aMed-showed a significant association with a lower risk of NPC (p-trends, <0.001-0.001). The odds ratios (95% confidence interval) comparing the extreme quartiles of the three significant scores were 0.47 (0.32-0.68) (HEI-2005), 0.48 (0.33-0.70) (aHEI), and 0.43 (0.30-0.62) (DQI-I). In gender-stratified analyses, the favorable association remained significant in men but not in women. We found that adherence to the predefined dietary patterns represented by the HEI-2005, aHEI, and DQI-I scales predicted a lower risk of NPC in adults from south China, especially in men. PMID:26927167

  4. Assessment of reporting consistency in a case-control study of spontaneous abortions.

    PubMed

    Fenster, L; Swan, S H; Windham, G C; Neutra, R R

    1991-03-01

    Reporting consistency was examined in a case-control study of spontaneous abortion in Santa Clara County, California. Each case (n = 100) and two pregnant controls (n = 200), frequency-matched by last menstrual period, were interviewed twice: first after the case's spontaneous abortion (on average, 24 weeks after the last menstrual period) and again after completion of the controls' pregnancies (on average, 48 wee