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Sample records for helios-i multicenter case-control

  1. 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

  2. Design and methods in a multi-center case-control interview study.

    PubMed Central

    Hartge, P; Cahill, J I; West, D; Hauck, M; Austin, D; Silverman, D; Hoover, R

    1984-01-01

    We conducted a case-control study in ten areas of the United States in which a total of 2,982 bladder cancer patients and 5,782 population controls were interviewed. We employed a variety of existing and new techniques to reduce bias and to monitor the quality of data collected. We review here many of the design elements and field methods that can be generally applied in epidemiologic studies, particularly multi-center interview studies, and explain the reasons for our selection of the methods, instruments, and procedures used. PMID:6689843

  3. Risk Factors for Contact Lens-Related Microbial Keratitis: A Case-Control Multicenter Study.

    PubMed

    Sauer, Arnaud; Meyer, Nicolas; Bourcier, Tristan

    2016-05-01

    The most feared complication of contact lens (CL) wear is microbial keratitis (MK), even though its incidence remains low. This study aimed to identify the risk factors of CL-related MK in a large, prospective, multicenter case-control study. A multicenter case-control study was designed. The CL-related MK subpopulation (Case) was compared with healthy CL wearers (Control) using a 52-item anonymous questionnaire designed to determine subject demographics and lens wear history. Univariate and multivariate logistic regression analyses were performed to compare both groups. The study enrolled 499 cases and 508 controls. The risk factors associated with the greatest increased odds of CL-related MK were as follows: using disinfecting solution more than 3 months (odds ratio [OR]=1.94), cosmetic CL wear and use of multipurpose disinfection solution (1.37 each), overnight wear, and soft lens use (OR=1.24 each). The protective factors associated with the greatest reduction in OR were fitting by an ophthalmologist (OR=0.73) and hyperopia versus myopia (OR=0.75). The infectious determinants were linked to the type of lenses, hygiene routine, CL handling, disinfecting solution, and storage case. This study aimed to highlight the increasingly CL-related MK, which likely occurs because of lack of patient information regarding basic rules of hygiene and CL care and handling.

  4. [Risk factors for contact lens-related microbial keratitis: A multicenter case-control study].

    PubMed

    Becmeur, P H; Abry, F; Bourcier, T; Meyer, N; Sauer, A

    2017-03-01

    Currently, the most feared complication by ophthalmologists of contact lens (CL) wear is microbial keratitis (MK), even though its incidence remains low. It is also a significant financial burden for society. This study aimed to identify the risk factors for CL-related MK especially with regard to hygiene and pattern of use, in a large, prospective, multicenter, case-control study. A multicenter retrospective case-control study was designed. The CL-related MK subpopulation (case) was compared with healthy CL wearers (control) using a 52-item anonymous questionnaire designed to determine subject demographics, lens wear history, lens type and disinfection solution, fitting, patient education, hygiene and maintenance of contact lenses, and patient history. Univariate logistic regression analysis was performed to compare both groups. The study included 497 cases and 364 controls. The risk factors associated with the greatest increased odds of CL-related MK were as follows: extended wear (OR=2.96 [1.65-5.33], P<0.001), occasional overnight lens use (OR=6.37 [4,55-8.90], P<0.001), fitting by an optician (OR=1.97 [1.38-2.83], P<0.001), absence of ophthalmologic exam (OR=6.56 [2-22], P<0.01) or no training in handling the contact lens (OR=4.47 [2.27-8.77], P<0.01), use of optician's disinfection solution (OR=5.55 [3.12-9.85], P<0.001), mixing solutions ("topping off") (OR=4.68 [2.73-8.04], P<0.001), no case replacement (OR=3.95 [2.28-6.82] P<0.01), no compliance with hygiene rules and smoking (OR=2.29 [1.67-3.14], P<0.01). The protective factors associated with the greatest reduction in OR were female gender (OR=0.49 [0.36-0.66], P<0.01), hypermetropia (OR=0.28 [0.16-0.48], P=0.01), rigid contact lens wear, fitting by an ophthalmologist, written and verbal instruction, and daily case maintenance. The knowledge of these risks factors incentivizes action at all levels to reduce the incidence of MK, from the prescriber to the patient, including the type of CL, case and

  5. Multicenter Case-Control Study on Restless Legs Syndrome in Multiple Sclerosis: the REMS Study

    PubMed Central

    Manconi, Mauro; Ferini-Strambi, Luigi; Filippi, Massimo; Bonanni, Enrica; Iudice, Alfonso; Murri, Luigi; Gigli, Gian Luigi; Fratticci, Lara; Merlino, Giovanni; Terzano, Giovanni; Granella, Franco; Parrino, Liborio; Silvestri, Rosalia; Aricò, Irene; Dattola, Vincenzo; Russo, Giovanna; Luongo, Carmela; Cicolin, Alessandro; Tribolo, Antonella; Cavalla, Paola; Savarese, Mariantonietta; Trojano, Maria; Ottaviano, Salvatore; Cirignotta, Fabio; Simioni, Valentina; Salvi, Fabrizio; Mondino, Fiorella; Perla, Franco; Chinaglia, Giorgia; Zuliani, Cristina; Cesnik, Edward; Granieri, Enrico; Placidi, Fabio; Palmieri, Maria Giuseppina; Manni, Raffaele; Terzaghi, Michele; Bergamaschi, Roberto; Rocchi, Raffaele; Ulivelli, Monica; Bartalini, Sabina; Ferri, Raffaele; Fermo, Salvatore Lo; Ubiali, Emilio; Viscardi, Massimo; Rottoli, Mariarosa; Nobili, Lino; Protti, Alessandra; Ferrillo, Franco; Allena, Marta; Mancardi, Gianluigi; Guarnieri, Biancamaria; Londrillo, Francesco

    2008-01-01

    Study objectives: To verify the existence of a symptomatic form of restless legs syndrome (RLS) secondary to multiple sclerosis (MS) and to identify possible associated risk factors. Design: Prospective, multicenter, case-control epidemiologic survey. Settings: Twenty sleep centers certified by the Italian Association of Sleep Medicine. Patients: Eight hundred and sixty-one patients affected by MS and 649 control subjects. Interventions: N/A. Measures and results: Data regarding demographic and clinical factors, presence and severity of RLS, the results of hematologic tests, and visual analysis of cerebrospinal magnetic resonance imaging studies were collected. The prevalence of RLS was 19% in MS and 4.2% in control subjects, with a risk to be affected by RLS of 5.4 (95%confidence interval: 3.56–8.26) times greater for patients with MS than for control subjects. In patients with MS, the following risk factors for RLS were significant: older age; longer MS duration; the primary progressive MS form; higher global, pyramidal, and sensory disability; and the presence of leg jerks before sleep onset. Patients with MS and RLS more often had sleep complaints and a higher intake of hypnotic medications than patients with MS without RLS. RLS associated with MS was more severe than that of control subjects. Conclusions: RLS is significantly associated with MS, especially in patients with severe pyramidal and sensory disability. These results strengthen the idea that the inflammatory damage correlated with MS may induce a secondary form of RLS. As it does in idiopathic cases, RLS has a significant impact on sleep quality in patients with MS; therefore, it should be always searched for, particularly in the presence of insomnia unresponsive to treatment with common hypnotic drugs. Citation: Manconi M; Ferini-Strambi L; Filippi M; Bonanni E; Iudice A; Murri L; Gigli GL; Fratticci L; Merlino G; Terzano G; Granella F; Parrino L; Silvestri R; Aricò I; Dattola V; Russo G; Luongo

  6. Occupation and risk of parkinsonism: a multicenter case-control study.

    PubMed

    Tanner, Caroline M; Ross, G Webster; Jewell, Sarah A; Hauser, Robert A; Jankovic, Joseph; Factor, Stewart A; Bressman, Susan; Deligtisch, Amanda; Marras, Connie; Lyons, Kelly E; Bhudhikanok, Grace S; Roucoux, Diana F; Meng, Cheryl; Abbott, Robert D; Langston, J William

    2009-09-01

    We examined risk of parkinsonism in occupations (agriculture, education, health care, welding, and mining) and toxicant exposures (solvents and pesticides) putatively associated with parkinsonism. To investigate occupations, specific job tasks, or exposures and risk of parkinsonism and clinical subtypes. Case-control. Eight movement disorders centers in North America. Inclusion criteria were parkinsonism (>or=2 cardinal signs), diagnosis within 8 years of recruitment (to minimize survival bias), and ability to participate in detailed telephone interviews. Control subjects were primarily nonblood relatives or acquaintances of patients. This multicenter case-control study compared lifelong occupational and job task histories to determine associations with parkinsonism and certain clinical subtypes (postural instability and gait difficulty and age at diagnosis

  7. Past medical history and pancreatic cancer risk: Results from a multicenter case-control study.

    PubMed

    Maisonneuve, Patrick; Lowenfels, Albert B; Bueno-de-Mesquita, H Bas; Ghadirian, Parviz; Baghurst, Peter A; Zatonski, Witold A; Miller, Anthony B; Duell, Eric J; Boffetta, Paolo; Boyle, Peter

    2010-02-01

    To investigate risk factors that may be linked to pancreatic cancer. We designed a multicenter population-based case-control (823 cases, 1679 control patients) study with data collection by using a common protocol and questionnaire. Participating centers were located in Australia, Canada, the Netherlands, and Poland. After adjustment for confounding factors, a positive history of pancreatitis was associated with pancreatic cancer (odds ratio [OR], 4.68; 95% confidence interval [95% CI], 2.23-9.84). The risk was especially high in heavy smokers (OR, 15.4; 95% CI, 3.18-74.9). Patients with diabetes had an increased risk of developing pancreatic cancer (OR, 2.16; 95% CI, 1.60-2.91). The risk was highest in the first year after the development of diabetes (OR, 6.68; 95% CI, 3.56-12.6) and decreased over time. A history of allergy was associated with a reduced risk of pancreas cancer (OR, 0.64; 95% CI, 0.50-0.82). Patients with newly diagnosed diabetes and patients with pancreatitis, particularly in heavy smokers, have an increased risk for developing pancreatic cancer. In addition to being risk factors, these conditions could be early manifestations of underlying pancreatic cancer. A history of allergy decreases the risk of pancreatic cancer. 2010 Elsevier Inc. All rights reserved.

  8. Environmental risk factors in pediatric psoriasis: a multicenter case-control study.

    PubMed

    Ozden, Müge G; Tekin, Nilgün S; Gürer, Mehmet A; Akdemir, Devrim; Doğramacı, Ciğdem; Utaş, Serap; Akman, Ayşe; Evans, Sibel E; Bahadır, Sevgi; Oztürkcan, Serap; Ikizoğlu, Güliz; Sendur, Neslihan; Köse, Osman; Bek, Yüksel; Yaylı, Savaş; Cantürk, Tayyar; Turanl, Ahmet Y

    2011-01-01

    To analyze the effect of possible risk factors, including breastfeeding, on the development of childhood-onset psoriasis, a multicenter case-control study with prospective collection of data was performed. Using a standard questionnaire, personal and specific variables including family history of psoriasis, maternal and environmental tobacco smoke exposure, body mass index (BMI), exclusive and partial breastfeeding for at least 3 and 12 months, cow's milk intake before 1 year, birth delivery method, and stressful life events were collected during 2009 from 537 patients with psoriasis and 511 controls younger than 18. Overall, patients more frequently reported exposure to environmental tobacco smoke at home and stressful life events in the year preceding the diagnosis than controls. The odds ratios (OR) for smoking and stressful life events were 2.90 (95% confidence interval [CI]=2.27-3.78) and 2.94 (95% CI=2.28-3.79), respectively. In addition, children with psoriasis were more likely to have a higher BMI (>26) than controls (OR=2.52; 95% CI=1.42-4.49). High BMI, environmental tobacco smoke exposure at home, and stressful life events may influence the development of pediatric psoriasis.

  9. Predictors of wound infection in elective colorectal surgery. Multicenter observational case-control study.

    PubMed

    Fraccalvieri, Doménico; Kreisler Moreno, Esther; Flor Lorente, Blas; Torres García, Antonio; Muñoz Calero, Alberto; Mateo Vallejo, Francisco; Biondo, Sebastiano

    2014-01-01

    The aim of this study is to evaluate the usefulness of Vicryl Plus(®) suture in reducing the rate of postoperative wound infection in elective colorectal surgery. A prospective case-control multicenter study with 480 patients undergoing elective colorectal surgery was performed between 2006 and 2007. Patients were divided in 2 groups of equal sample size: group 1, closure of the abdominal wall using Vicryl Plus(®) and group 2 where PDS II(®) was used. The study involved 5 hospitals in the Spanish State. Wound infection was classified into superficial and deep. All patients diagnosed of wound infection during the hospital stay and up to 30 days after discharge were studied. For the statistical analysis Chi-square test and Fisher exact were used for bivariate analysis and logistic regression model for multivariate analysis. Wound infection rates were significantly lower in group 1: 14.6 vs. 29.2. Multivariate analysis showed that risk of wound infection was higher in patients with cancer, lung disease, anemia, operative time greater than 2 h, lack of second dose intra-operative prophylactic antibiotic and laparotomy closure with PDS suture II(®). The use of suture coated with triclosan can be an effective prophylactic tool in reducing wound infection rate in patients undergoing elective colorectal surgery. Copyright © 2013 AEC. Published by Elsevier Espana. All rights reserved.

  10. Multicenter case-control study on restless legs syndrome in multiple sclerosis: the REMS study.

    PubMed

    Manconi, Mauro; Ferini-Strambi, Luigi; Filippi, Massimo; Bonanni, Enrica; Iudice, Alfonso; Murri, Luigi; Gigli, Gian Luigi; Fratticci, Lara; Merlino, Giovanni; Terzano, Giovanni; Granella, Franco; Parrino, Liborio; Silvestri, Rosalia; Aricò, Irene; Dattola, Vincenzo; Russo, Giovanna; Luongo, Carmela; Cicolin, Alessandro; Tribolo, Antonella; Cavalla, Paola; Savarese, Mariantonietta; Trojano, Maria; Ottaviano, Salvatore; Cirignotta, Fabio; Simioni, Valentina; Salvi, Fabrizio; Mondino, Fiorella; Perla, Franco; Chinaglia, Giorgia; Zuliani, Cristina; Cesnik, Edward; Granieri, Enrico; Placidi, Fabio; Palmieri, Maria Giuseppina; Manni, Raffaele; Terzaghi, Michele; Bergamaschi, Roberto; Rocchi, Raffaele; Ulivelli, Monica; Bartalini, Sabina; Ferri, Raffaele; Lo Fermo, Salvatore; Ubiali, Emilio; Viscardi, Massimo; Rottoli, Mariarosa; Nobili, Lino; Protti, Alessandra; Ferrillo, Franco; Allena, Marta; Mancardi, Gianluigi; Guarnieri, Biancamaria; Londrillo, Francesco

    2008-07-01

    To verify the existence of a symptomatic form of restless legs syndrome (RLS) secondary to multiple sclerosis (MS) and to identify possible associated risk factors. Prospective, multicenter, case-control epidemiologic survey. Twenty sleep centers certified by the Italian Association of Sleep Medicine. Eight hundred and sixty-one patients affected by MS and 649 control subjects. N/A. Data regarding demographic and clinical factors, presence and severity of RLS, the results of hematologic tests, and visual analysis of cerebrospinal magnetic resonance imaging studies were collected. The prevalence of RLS was 19% in MS and 4.2% in control subjects, with a risk to be affected by RLS of 5.4 (95%confidence interval: 3.56-8.26) times greater for patients with MS than for control subjects. In patients with MS, the following risk factors for RLS were significant: older age; longer MS duration; the primary progressive MS form; higher global, pyramidal, and sensory disability; and the presence of leg jerks before sleep onset. Patients with MS and RLS more often had sleep complaints and a higher intake of hypnotic medications than patients with MS without RLS. RLS associated with MS was more severe than that of control subjects. RLS is significantly associated with MS, especially in patients with severe pyramidal and sensory disability. These results strengthen the idea that the inflammatory damage correlated with MS may induce a secondary form of RLS. As it does in idiopathic cases, RLS has a significant impact on sleep quality in patients with MS; therefore, it should be always searched for, particularly in the presence of insomnia unresponsive to treatment with common hypnotic drugs.

  11. Macrophage activation syndrome in systemic lupus erythematosus: a multicenter, case-control study in China.

    PubMed

    Liu, Ai-Chun; Yang, Yue; Li, Meng-Tao; Jia, Yuan; Chen, Sheng; Ye, Shuang; Zeng, Xiang-Zong; Wang, Zhao; Zhao, Jin-Xia; Liu, Xiang-Yuan; Zhu, Jian; Zhao, Yan; Zeng, Xiao-Feng; Li, Zhan-Guo

    2017-04-13

    The objective of this study was to describe the clinical and laboratory characteristics, precipitating factors, treatment, and outcome of macrophage activation syndrome (MAS) complicating systemic lupus erythematosus (SLE). A multicenter case-control study was performed across six tertiary hospitals from 1997 to 2014. A total of 32 patients with SLE-associated MAS were enrolled. Sixty-four age- and sex-matched SLE patients diagnosed in the same period without MAS episodes were selected as controls. The most frequent clinical feature was fever, followed by splenomegaly. Hyperferritinemia, hypoalbuminemia, and hyper-lactate dehydrogenase (LDH)-nemia were among the most common laboratory abnormalities. Compared with pre-MAS visit, patients at the onset of MAS had greater frequencies of renal involvement, liver dysfunction, and cytopenia. Receiver operating characteristic (ROC) analysis identified optimal cutoff values of ferritin (>662.5 ng/mL) and LDH (>359 U/mL) to predict the occurrence of MAS in SLE. SLE flare and infection were the common triggers of MAS in SLE. Abortion and parturition were recorded as well. The overall mortality rate was 12.5%. All patients received corticosteroids. Cyclosporine A, cyclophosphamide, and etoposide were the three most commonly used immunosuppressants. Rituximab was given to one patient. Intravenous immunoglobulin (IVIG) was added for 46.9% patients. MAS is a potentially fatal complication of SLE. Its occurrence is most frequently associated with active SLE disease or infection. The presentation of unexplained fever, cytopenia, or liver dysfunction, with high levels of ferritin and LDH, in patients with SLE should raise the suspicion of MAS. Corticosteroids with immunosuppressants and IVIG may be an appropriate treatment.

  12. Diet and risk of adult leukemia: a multicenter case-control study in China.

    PubMed

    Liu, Ping; Holman, C D'Arcy J; Jin, Jie; Zhang, Min

    2015-08-01

    Epidemiologic studies on diet and leukemia risk have shown inconsistent results. This study examined the associations between dietary factors and the risk of adult leukemia in Chinese populations. A multicenter case-control study was conducted in southeast and northeast China between 2008 and 2013. It included 442 incident cases with hematologically confirmed leukemia and 442 controls, individually match to cases by gender, birth quinquennium, and study site. Information on diet was sought from face-to-face interviews using a validated and reliable 103-item food frequency questionnaire. Odds ratios (ORs) and confidence intervals (CIs) were estimated by conditional logistic regression. Vegetables intake was associated with decreased risk of adult leukemia, with a significant dose-response relationship and adjusted OR of 0.30 (95 % CI 0.18-0.50) for the highest versus the lowest quartiles intake. Compared with non-consumers, the adjusted OR was 0.51 (95 % CI 0.29-0.93) for those who consumed milk at the highest tertile. Intakes of fruits, red meat, poultry, and fish were not associated with the risk. Dietary nutrients, including dietary fiber, carotenoids, vitamins B1, B2, and C, niacin, and folate, were significantly associated with reduced risks. Elevated risk was related to dietary intake animal fat and dietary habits with frequent intakes of fat, deep-fried, and smoked foods ( p for trend <0.05). Our findings suggest that diets rich in vegetables and adequate amount of milk reduce the risk of adult leukemia, whereas diets preferring fat, deep-fried, and smoked foods increase the risk in Chinese populations.

  13. Mobile phone use and brain tumors in children and adolescents: a multicenter case-control study.

    PubMed

    Aydin, Denis; Feychting, Maria; Schüz, Joachim; Tynes, Tore; Andersen, Tina Veje; Schmidt, Lisbeth Samsø; Poulsen, Aslak Harbo; Johansen, Christoffer; Prochazka, Michaela; Lannering, Birgitta; Klæboe, Lars; Eggen, Tone; Jenni, Daniela; Grotzer, Michael; Von der Weid, Nicolas; Kuehni, Claudia E; Röösli, Martin

    2011-08-17

    It has been hypothesized that children and adolescents might be more vulnerable to possible health effects from mobile phone exposure than adults. We investigated whether mobile phone use is associated with brain tumor risk among children and adolescents. CEFALO is a multicenter case-control study conducted in Denmark, Sweden, Norway, and Switzerland that includes all children and adolescents aged 7-19 years who were diagnosed with a brain tumor between 2004 and 2008. We conducted interviews, in person, with 352 case patients (participation rate: 83%) and 646 control subjects (participation rate: 71%) and their parents. Control subjects were randomly selected from population registries and matched by age, sex, and geographical region. We asked about mobile phone use and included mobile phone operator records when available. Odds ratios (ORs) for brain tumor risk and 95% confidence intervals (CIs) were calculated using conditional logistic regression models. Regular users of mobile phones were not statistically significantly more likely to have been diagnosed with brain tumors compared with nonusers (OR = 1.36; 95% CI = 0.92 to 2.02). Children who started to use mobile phones at least 5 years ago were not at increased risk compared with those who had never regularly used mobile phones (OR = 1.26, 95% CI = 0.70 to 2.28). In a subset of study participants for whom operator recorded data were available, brain tumor risk was related to the time elapsed since the mobile phone subscription was started but not to amount of use. No increased risk of brain tumors was observed for brain areas receiving the highest amount of exposure. The absence of an exposure-response relationship either in terms of the amount of mobile phone use or by localization of the brain tumor argues against a causal association.

  14. Risk and protective factors for falls from furniture in young children: multicenter case-control study.

    PubMed

    Kendrick, Denise; Maula, Asiya; Reading, Richard; Hindmarch, Paul; Coupland, Carol; Watson, Michael; Hayes, Mike; Deave, Toity

    2015-02-01

    Falls from furniture are common in young children but there is little evidence on protective factors for these falls. To estimate associations for risk and protective factors for falls from furniture in children aged 0 to 4 years. Multicenter case-control study at hospitals, minor injury units, and general practices in and around 4 UK study centers. Recruitment commenced June 14, 2010, and ended April 27, 2012. Participants included 672 children with falls from furniture and 2648 control participants matched on age, sex, calendar time, and study center. Thirty-five percent of cases and 33% of control individuals agreed to participate. The mean age was 1.74 years for cases and 1.91 years for control participants. Fifty-four percent of cases and 56% of control participants were male. Exposures included safety practices, safety equipment use, and home hazards. Falls from furniture occurring at the child's home resulting in attendance at an emergency department, minor injury unit, or hospital admission. Compared with parents of control participants, parents of cases were significantly more likely not to use safety gates in the home (adjusted odds ratio [AOR], 1.65; 95% CI, 1.29-2.12) and not to have taught their children rules about climbing on kitchen objects (AOR, 1.58; 95% CI, 1.16-2.15). Cases aged 0 to 12 months were significantly more likely to have been left on raised surfaces (AOR, 5.62; 95% CI, 3.62-8.72), had their diapers changed on raised surfaces (AOR, 1.89; 95% CI, 1.24-2.88), and been put in car/bouncing seats on raised surfaces (AOR, 2.05; 95% CI, 1.29-3.27). Cases 3 years and older were significantly more likely to have played or climbed on furniture (AOR, 9.25; 95% CI, 1.22-70.07). Cases were significantly less likely to have played or climbed on garden furniture (AOR, 0.74; 95% CI, 0.56-0.97). If estimated associations are causal, some falls from furniture may be prevented by incorporating advice into child health contacts, personal child health

  15. A multicenter, matched case-control study of risk factors for equine laminitis.

    PubMed

    Alford, P; Geller, S; Richrdson, B; Slater, M; Honnas, C; Foreman, J; Robinson, J; Messer, M; Roberts, M; Goble, D; Hood, D; Chaffin, M

    2001-05-01

    Risk factors for equine laminitis were examined in a prospective case-control study of the 258 cases seen at six collaborating veterinary teaching hospitals over a 32-month period. Case-control pairs were matched on institution, clinician, and season of diagnosis. The 90% of case-control pairs (78 acute, 155 chronic) that had complete data for age, gender, and breed were used in separate conditional logistic-regression models for acute and chronic laminitis. There was an increase in risk for horses with acute laminitis from 5 to 7 years of age (OR 4.7, 95% CI 1.3-16) and from 13 to 31 years of age (OR 3.9, 95% CI 1.3-12) (both compared to <5 years); risk was increased for chronic laminitis from 10 to 14 years (OR 3, 95% CI 1.4-6.8) and from 15 to 38 years (OR 2.9, 95% CI 1.4-6.1) (both compared to <6 years). Mares - but not stallions - were more likely than geldings to develop acute laminitis (OR 2.6, 95% CI 1.1-6.2) and chronic laminitis (OR 2.0, 95% CI 1.1-3.6). In the small acute-laminitis data set, the breed variable was collapsed into three categories: Thoroughbred (THB, reference), the Quarter Horse (QH), and other (non-QH-THB). The non-QH-THB group was at increased risk of acute laminitis (OR 3.8, 95% CI 1.2-11.8). For the seven breed-group categories used in the chronic-laminitis model, however, all non-THB breed groups appeared significantly at risk as compared to the THB, with odds ratios ranging from 3.3 (95% CI 1.3-8.30) for the QH to 9.1 (95% CI 2.1-39.3) for ponies.

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

    PubMed

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

    2016-01-01

    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. 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). 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. 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.

  17. 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

  18. A multicenter case-control study of risk factors for equine protozoal myeloencephalitis.

    PubMed

    Cohen, Noah D; Mackay, Robert J; Toby, Ellen; Andrews, Frank M; Barr, Bonnie S; Beech, Jill; Bernard, William V; Clark, Carol K; Divers, Thomas J; Furr, Martin O; Kohn, Catherine W; Levy, Michel; Reed, Stephen M; Seahorn, Thomas L; Slovis, Nathan M

    2007-12-15

    To identify risk factors for equine protozoal myeloencephalitis (EPM) among horses examined at 11 equine referral hospitals. Case-control study. 183 horses with EPM, 297 horses with neurologic disease other than EPM (neurologic controls), and 168 horses with non-neurologic diseases (non-neurologic controls) examined at 11 equine referral hospitals in the United States. A study data form was completed for all horses. Data were compared between the case group and each of the control groups by means of bivariate and multivariate polytomous logistic regression. Relative to neurologic control horses, case horses were more likely to be > or = 2 years old and to have a history of cats residing on the premises. Relative to non-neurologic control horses, case horses were more likely to be used for racing or Western performance. Results indicated that cats may play a role in the natural epidemiology of EPM, that the disease is less common among horses < 2 years of age relative to other neurologic diseases, and that horses used for particular types of competition may have an increased risk of developing EPM.

  19. Urinary bladder cancer risk factors in Egypt: a multi-center case-control study

    PubMed Central

    Zheng, Yun-Ling; Amr, Sania; Saleh, Doa’a A.; Dash, Chiranjeev; Ezzat, Sameera; Mikhail, Nabiel N.; Gouda, Iman; Loay, Iman; Hifnawy, Tamer; Abdel-Hamid, Mohamed; Khaled, Hussein; Wolpert, Beverly; Abdel-Aziz, Mohamed A.; Loffredo, Christopher A.

    2011-01-01

    Background We investigated associations between tobacco exposure, history of schistosomiasis and bladder cancer risk in Egypt. Methods We analyzed data from a case-control study (1,886 newly diagnosed and histologically confirmed cases and 2,716 age-, gender-, and residence-matched, population-based controls). Using logistic regression we estimated the covariate-adjusted odds ratios (OR) and 95% confidence interval (CI) of the associations. Results Among men, cigarette smoking was associated with an increased risk of urothelial carcinoma (UC) (OR = 1.8, 95% CI = 1.4, 2.2), but not squamous cell carcinoma (SCC); smoking both waterpipes and cigarettes was associated with an even greater risk for UC (OR = 2.9, 95% CI = 2.1, 3.9) and a statistically significant risk for SCC (OR = 1.8, 95% CI = 1.2, 2.6). Among non-smoking men and women, to environmental tobacco smoke exposure was associated with an increased risk of UC. History of schistosomiasis was associated with increased risk of both UC (OR = 1.9, 95% CI = 1.2, 2.9) and SCC (OR = 1.9, 95% CI = 1.2, 3.0) in women and to a lesser extent (OR = 1.4, 95% CI = 1.2, 1.7 and OR = 1.4, 95% CI = 1.1, 1.7, for UC and SCC respectively) in men. Conclusions The results suggest that schistosomiasis and tobacco smoking increase the risk of both SCC and UC. Impact This study provides new evidence for associations between bladder cancer subtypes and schistosomiasis, and suggests that smoking both cigarettes and waterpipes increases the risk for SCC and UC in Egyptian men. PMID:22147365

  20. Meat consumption, genetic susceptibility, and colon cancer risk: a United States multicenter case-control study.

    PubMed

    Kampman, E; Slattery, M L; Bigler, J; Leppert, M; Samowitz, W; Caan, B J; Potter, J D

    1999-01-01

    Meat consumption may especially increase risk of colon cancer when the meat is prepared at high temperatures and consumed by subjects with an inherited susceptibility to well-done meat. In this United States case-control study, the association between meat consumption, genetic susceptibility, and colon cancer risk was studied. Meat consumption data were available from a detailed diet history questionnaire and from questions about methods of preparation. Molecular variants in the carcinogen-metabolizing genes NAT2 and GSTM1 were determined in DNA extracted from WBCs. A total of 1542 cases and 1860 population-based controls were included in these analyses. The amount of red and white meat consumed was not associated with overall colon cancer risk. Processed meat consumption was weakly positively associated with colon cancer risk in men only (odds ratio for highest versus lowest quintile of intake = 1.4, 95% confidence interval = 1.0-1.9). The frequency of fried, broiled, baked, or barbecued meat, use of drippings, and doneness of meat were not significantly associated with risk. The Mutagen Index, as an estimate for exposure to mutagenic or carcinogenic substances, was slightly positively associated with colon cancer risk in men (odds ratio = 1.3, 95% confidence interval = 1.0-1.7). No significant associations with colon cancer risk were observed for different NAT2 and GSTM1 gene variants. The observed associations with processed meat and the Mutagen Index were strongest for those with the intermediate or rapid NAT2 acetylator phenotype. Associations were not markedly influenced by lack of the GSTM1 gene. This study provides little support for an association between meat consumption and colon cancer risk but does provide some, albeit not strong, evidence for a modifying effect of molecular variants of the NAT2 gene.

  1. [Risk factors for methicillin-resistant Staphylococcus aureus bacteremia: A multicenter matched case-control study].

    PubMed

    Arias-Ortiz, Paola Mariana; Calderón, Libia Del Pilar; Castillo, Juan Sebastián; Moreno, José; Leal, Aura Lucía; Cortés, Jorge Alberto; Álvarez, Carlos Arturo; Grebo, Grupo

    2016-12-01

    Methicillin-resistant Staphylococcus aureus is a frequent pathogen at critical care services. Its presence leads to increased hospital stays and mortality risk in patients with bacteremia. However, the etiology of this resistance marker has not been fully studied. To identify risk factors associated with the emergence of methicillin-resistant S. aureus bacteremia in critically ill patients treated at intensive care units in Bogotá, Colombia. We conducted a retrospective paired case-control study, nested in a cohort of patients diagnosed with S. aureus bacteremia and treated at intensive care units between 2006 and 2008 in Bogotá. Cases were patients with positive blood culture to methicillin resistance, matched in a 1:1 ratio with methicillin-sensitive controls isolated from the same institution and hospitalization year. We used conditional logistic regression to analyze the risk factors associated with the presence of resistance, with emphasis on prior antibiotic therapy. We included 372 patients with S. aureus bacteremia. Factors such as the use of pre-hospital devices: vascular (OR=1.986, 95% CI 1.038 to 3.801) and urinary (OR=2.559, 95% CI: 1.170 to 5.596), along with the number of previously used antibiotics, were associated with the emergence of resistance. The number of antibiotics used previously was determined to have a gradient effect, particularly carbapenems. The rational use of antibiotics and surveillance of exposure to surgical procedures or use of invasive devices are interventions that could diminish the emergence of methicillin-resistant S. aureus bacteremia causes.

  2. Active and involuntary tobacco smoking and upper-aerodigestive-tract cancer risks in a multicenter case-control study

    PubMed Central

    Lee, Yuan-Chin Amy; Marron, Manuela; Benhamou, Simone; Bouchardy, Christine; Ahrens, Wolfgang; Pohlabeln, Hermann; Lagiou, Pagona; Trichopoulos, Dimitrios; Agudo, Antonio; Castellsague, Xavier; Bencko, Vladimir; Holcatova, Ivana; Kjaerheim, Kristina; Merletti, Franco; Richiardi, Lorenzo; Macfarlane, Gary J.; Macfarlane, Tatiana V.; Talamini, Renato; Barzan, Luigi; Canova, Cristina; Simonato, Lorenzo; Conway, David I.; McKinney, Patricia A.; Lowry, Raymond J.; Sneddon, Linda; Znaor, Ariana; Healy, Claire M.; McCartan, Bernard E.; Brennan, Paul; Hashibe, Mia

    2012-01-01

    Introduction Several important issues for the established association between tobacco smoking and upper-aerodigestive tract (UADT) cancer risks include the associations with smoking by cancer subsite, by type of tobacco, and among never alcohol drinkers, and the associations with involuntary smoking among nonsmokers. Our aim was to examine these specific issues in a large scale case-control study in Europe. Methods Analysis was performed on 2,103 UADT squamous cell carcinoma cases and 2,221 controls in the Alcohol-Related Cancers and Genetic Susceptibility in Europe (ARCAGE) project, a multicenter case-control study in 10 European countries. Unconditional logistic regression was performed to obtain odds ratios (OR) and 95% confidence intervals (CI). Results Compared to never tobacco smoking, current smoking was associated with UADT cancer risks (OR=6.72, 95% CI 5.45–8.30 for overall; 5.83, 4.50–7.54 for oral cavity and oropharynx; 12.19, 8.29–17.92 for hypopharynx and larynx; 4.17, 2.45–7.10 for esophagus). Among never drinkers, dose-response relationships with tobacco smoking packyears were observed for hypopharyngeal and laryngeal cancers (ptrend = 0.01), but not for oral cavity and oropharyngeal cancers (ptrend = 0.282). Among never smokers, ever exposure to involuntary smoking was associated with an increased risk of UADT cancers (OR=1.60, 95% CI 1.04–2.46). Conclusion Our results corroborate that tobacco smoking may play a stronger role in the development of hypopharyngeal and laryngeal cancers than that of oral cavity and oropharyngeal cancers among never drinkers and that involuntary smoking is an important risk factor for UADT cancers. Public health interventions to reduce involuntary smoking exposure could help reduce UADT cancer incidence. PMID:19959682

  3. Nocardia Infection in Solid Organ Transplant Recipients: A Multicenter European Case-control Study.

    PubMed

    Coussement, Julien; Lebeaux, David; van Delden, Christian; Guillot, Hélène; Freund, Romain; Marbus, Sierk; Melica, Giovanna; Van Wijngaerden, Eric; Douvry, Benoit; Van Laecke, Steven; Vuotto, Fanny; Tricot, Leïla; Fernández-Ruiz, Mario; Dantal, Jacques; Hirzel, Cédric; Jais, Jean-Philippe; Rodriguez-Nava, Veronica; Lortholary, Olivier; Jacobs, Frédérique

    2016-08-01

    Nocardiosis is a rare, life-threatening opportunistic infection, affecting 0.04% to 3.5% of patients after solid organ transplant (SOT). The aim of this study was to identify risk factors for Nocardia infection after SOT and to describe the presentation of nocardiosis in these patients. We performed a retrospective case-control study of adult patients diagnosed with nocardiosis after SOT between 2000 and 2014 in 36 European (France, Belgium, Switzerland, the Netherlands, Spain) centers. Two control subjects per case were matched by institution, transplant date, and transplanted organ. A multivariable analysis was performed using conditional logistic regression to identify risk factors for nocardiosis. One hundred and seventeen cases of nocardiosis and 234 control patients were included. Nocardiosis occurred at a median of 17.5 (range, 2-244) months after transplant. In multivariable analysis, high calcineurin inhibitor trough levels in the month before diagnosis (odds ratio [OR], 6.11; 95% confidence interval [CI], 2.58-14.51), use of tacrolimus (OR, 2.65; 95% CI, 1.17-6.00) and corticosteroid dose (OR, 1.12; 95% CI, 1.03-1.22) at the time of diagnosis, patient age (OR, 1.04; 95% CI, 1.02-1.07), and length of stay in the intensive care unit after SOT (OR, 1.04; 95% CI, 1.00-1.09) were independently associated with development of nocardiosis; low-dose cotrimoxazole prophylaxis was not found to prevent nocardiosis. Nocardia farcinica was more frequently associated with brain, skin, and subcutaneous tissue infections than were other Nocardia species. Among the 30 cases with central nervous system nocardiosis, 13 (43.3%) had no neurological symptoms. We identified 5 risk factors for nocardiosis after SOT. Low-dose cotrimoxazole was not found to prevent Nocardia infection. These findings may help improve management of transplant recipients. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For

  4. 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

  5. Occupational and environmental risk factors for idiopathic pulmonary fibrosis in Egypt: a multicenter case-control study.

    PubMed

    Awadalla, N J; Hegazy, A; Elmetwally, R A; Wahby, I

    2012-07-01

    Despite the advances in medical therapy and technology, the prognosis of idiopathic pulmonary fibrosis (IPF) remains poor and the need for disease prevention based on identifying the risk factors becomes mandatory. Occupational and environmental exposures were studied in several countries and found to play important role in the disease development. However, in Egypt, a little attention has been paid to study the effect of these factors in the disease development. To identify the occupational and environmental risk factors associated with the development of IPF in Egypt. A multicenter hospital-based case-control study was carried out in chest hospitals affiliated to three Egyptian cities-Cairo, Tanta and Mansoura. Subjects were 201 patients with confirmed IPF (cases) and 205 age-, sex- and residence-matched controls. Data on occupational and environmental factors were obtained from a questionnaire. Multiple logistic regression analysis was used to determine the independent risk factors of IPF in both sexes for single factors with adjustment for age, residence and smoking status. Compared with the controls, the risk of IPF in male workers was observed to increase significantly in chemical and petrochemical industries and carpentry and wood working (OR = 2.56, 95% CI: 1.02-7.01), and with occupational exposures to wood dust and wood preservatives. Among female workers, a significant increase was observed in farming (OR = 3.34, 95% CI: 1.17-10.12), raising birds and occupational exposures to animal feeds, products and dusts and pesticides. Risk of IPF decreased significantly in male workers and insignificantly among female workers in sales and clerical related activities. The environmental exposures to birds and cats were significantly associated with elevated risk of IPF development in both sexes. In Egypt, farming, raising birds and wood working are important risk factors for the development of IPF.

  6. Occupation and risk of lung cancer in Central and Eastern Europe: the IARC multi-center case-control study.

    PubMed

    Bardin-Mikolajczak, Alicja; Lissowska, Jolanta; Zaridze, David; Szeszenia-Dabrowska, Neonila; Rudnai, Peter; Fabianova, Eleonora; Mates, Dana; Navratilova, Marie; Bencko, Vladimir; Janout, Vladimir; Fevotte, Joelle; Fletcher, Tony; 't Mannetje, Andrea; Brennan, Paul; Boffetta, Paolo

    2007-08-01

    We sought to evaluate the role of occupation and industry in lung carcinogenesis in six countries in Central and Eastern Europe. This multi-center case-control study included 2,056 male and 576 female lung cancer incidence cases diagnosed from 1998 to 2001 and 2,144 male and 727 female controls frequency-matched for sex and age. Unconditional regression models were applied to calculate the odds ratios after controlling for potential confounders including age (5-year groups), study center (15 centers), and tobacco pack-years. Elevated odds ratios (ORs) were found for men employed as production workers (OR 1.45, 95% CI 1.22-1.72), bookkeepers and cashiers (1.81, 1.03-3.24), general farmers (1.67, 1.08-2.60), livestock workers (2.54, 1.09-5.88), miners (2.17, 1.47-3.23), toolmakers and metal patternmakers (2.56, 1.34-4.94), glass formers (2.55, 1.18-5.50), dockworkers, and freight handlers (1.49, 1.04-2.12). Industries with elevated risk among men included mining (1.75, 1.20-2.57), manufacture of cement, lime, or plaster (3.62, 1.11-12.00), casting of metals (2.00, 1.17-3.45), manufacture of electric motors (2.18, 1.24-3.86). For women, elevated ORs were found for medical, dental, veterinary doctors (2.54, 1.01-6.31), librarians and curators (7.03, 1.80-27.80), sewers 3.63 (1.12-10.23). This study identifies new areas for further, explanatory analyses, especially in production work, and indicates new possible sources of exposure to cancer risk for women.

  7. Protocol of the Stroke in Korean Young Adults Study: A Multicenter Case-Control Study and Prospective Cohort Study.

    PubMed

    Kwon, Hyuk Sung; Kim, Chulho; Lee, Seung-Hoon; Jung, Keun-Hwa; Kim, Young Dae; Kwon, Hyung-Min; Heo, Sung Hyuk; Chang, Dae-Il; Kim, Beom Joon; Kim, Jeong-Min; Kim, Hyun Young; Kim, Young Seo

    2016-06-01

    The incidence of ischemic stroke in young adults has been rising over recent decades, but there is still limited information on its risk factors, etiologies, and outcomes. Because these patients generally participate in social life, risk factors associated with lifestyle may have a great impact and need to be identified. The SKY (Stroke in Korean Young Adults) study is a multicenter case-control study and a prospective cohort study in 8 tertiary medical centers in the Republic of Korea. The case subjects are patients aged 18-44 years with first-ever ischemic stroke occurring within 1 month of stroke onset, and the control subjects are age- and gender-matched community controls. Our aim is to include 470 cases and 470 controls. The main objective of our study is to determine the risk factors and the causes of ischemic stroke in Korean young adults. Both well-documented risk factors and little-known lifestyle-related risk factors such as lifestyle habits and psychological distress including job strain will be evaluated by comparing cases and controls using a structured questionnaire. Secondary objectives are to determine the risks of mortality, recurrent vascular events, and poststroke epilepsy in these patients. Conditional logistic regression analysis will be used to estimate odds ratios and 95% confidence intervals. The SKY study is designed to obtain more insights into relatively little-known risk factors in young Korean adults with ischemic stroke. The results may also help identify the frequencies of uncommon etiologies and outcomes in these patients. Copyright © 2016 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  8. Smoking addiction and the risk of upper-aerodigestive-tract cancer in a multicenter case-control study.

    PubMed

    Lee, Yuan-Chin Amy; Zugna, Daniela; Richiardi, Lorenzo; Merletti, Franco; Marron, Manuela; Ahrens, Wolfgang; Pohlabeln, Hermann; Lagiou, Pagona; Trichopoulos, Dimitrios; Agudo, Antonio; Castellsague, Xavier; Betka, Jaroslav; Holcatova, Ivana; Kjaerheim, Kristina; Macfarlane, Gary J; Macfarlane, Tatiana V; Talamini, Renato; Barzan, Luigi; Canova, Cristina; Simonato, Lorenzo; Conway, David I; McKinney, Patricia A; Thomson, Peter; Znaor, Ariana; Healy, Claire M; McCartan, Bernard E; Boffetta, Paolo; Brennan, Paul; Hashibe, Mia

    2013-12-01

    Although previous studies on tobacco and alcohol and the risk of upper-aerodigestive-tract (UADT) cancers have clearly shown dose-response relations with the frequency and duration of tobacco and alcohol, studies on addiction to tobacco smoking itself as a risk factor for UADT cancer have not been published, to our knowledge. The aim of this report is to assess whether smoking addiction is an independent risk factor or a refinement to smoking variables (intensity and duration) for UADT squamous cell carcinoma (SCC) risk in the multicenter case-control study (ARCAGE) in Western Europe. The analyses included 1,586 ever smoking UADT SCC cases and 1,260 ever smoking controls. Addiction was measured by a modified Fagerström score (first cigarette after waking up, difficulty refraining from smoking in places where it is forbidden and cigarettes per day). Adjusted odds ratios (ORs) and 95% confidence intervals (95% CIs) for UADT cancers with addiction variables were estimated with unconditional logistic regression. Among current smokers, the participants who smoked their first cigarette within 5 min of waking up were two times more likely to develop UADT SCC than those who smoked 60 min after waking up. Greater tobacco smoking addiction was associated with an increased risk of UADT SCC among current smokers (OR = 3.83, 95% CI: 2.56-5.73 for score of 3-7 vs. 0) but not among former smokers. These results may be consistent with a residual effect of smoking that was not captured by the questionnaire responses (smoking intensity and smoking duration) alone, suggesting addiction a refinement to smoking variables. Copyright © 2013 UICC.

  9. Adult female acne and associated risk factors: Results of a multicenter case-control study in Italy.

    PubMed

    Di Landro, Anna; Cazzaniga, Simone; Cusano, Francesco; Bonci, Angela; Carla, Cardinali; Musumeci, Maria Letizia; Patrizi, Annalisa; Bettoli, Vincenzo; Pezzarossa, Enrico; Caproni, Marzia; Fortina, Anna Belloni; Campione, Elena; Ingordo, Vito; Naldi, Luigi

    2016-12-01

    The reasons for the appearance of acne in adulthood are largely unknown. We explored the role of personal and environmental factors in adult female acne. We conducted a multicenter case-control study in the outpatient departments of 12 Italian cities. Cases (n = 248) were consecutive women ≥25 years of age with newly diagnosed acne of any grade. Controls (n = 270) were females diagnosed with conditions other than acne. In multivariate analysis, a history of acne in parents (odds ratio [OR] = 3.02) or siblings (OR = 2.40), history of acne during adolescence (OR = 5.44), having no previous pregnancies (OR = 1.71), having hirsutism (OR = 3.50), being an office worker versus being unemployed or being a housewife (OR = 2.24), and having a high level of reported psychological stress (OR = 2.95) were all associated with acne. A low weekly intake of fruits or vegetables (OR = 2.33) and low consumption of fresh fish (OR = 2.76) were also associated with acne. We did not establish an onset date for acne. Some of our associations may reflect consequences of established acne. Lifestyle factors may play an important role for acne development in adulthood, but their role should be further assessed in prospective studies. Copyright © 2016 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

  10. 77 FR 12598 - Notice Correction; A Multi-Center International Hospital-Based Case-Control Study of Lymphoma in...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-01

    ...-Based Case-Control Study of Lymphoma in Asia (AsiaLymph) (NCI) The Federal Register notice published on... international hospital-based case-control study of lymphoma in Asia (AsiaLymph) (NCI)'' was submitted with...

  11. Factors associated to temporal artery biopsy result in suspects of giant cell arteritis: a retrospective, multicenter, case-control study.

    PubMed

    González-López, Julio J; González-Moraleja, Julio; Burdaspal-Moratilla, Ana; Rebolleda, Gema; Núñez-Gómez-Álvarez, María T; Muñoz-Negrete, Francisco J

    2013-12-01

    To evaluate the positivity rate of temporal artery biopsies (TAB) performed in suspects of giant cell arteritis (GCA) and to study the epidemiological and clinical factors associated to the biopsy result. A retrospective, multicenter, case-control study was performed, including three hundred and thirty-five patients who underwent TAB for a suspicion of GCA from 2001 to 2010. Clinical, epidemiological and pathology data were recovered from the patients' clinical records. Histologic diagnosis of GCA was made when active inflammation or giant cells were found in the arterial wall. Eighty-one biopsies (24.2%) were considered positive for GCA. Clinical factors independently associated to TAB result in a logistic regression analysis were temporal cutaneous hyperalgesia (OR = 10.8; p < 0.001), jaw claudication (OR = 4.6; p = 0.001), recent-onset headache (OR = 4.4; p = 0.001), decreased temporal pulse (OR = 2.8; p = 0.02), pain and stiffness in neck and shoulders (OR = 2.3; p = 0.05), unintentional weight loss (OR = 1.33; p = 0.003) and age (OR = 1.085; p = 0.004). Other factors such as length of the surgical specimen (OR = 1.079; p = 0.028) and erythrocyte sedimentation rate (OR = 1.042; p < 0.001) were also statistically significant. The model was accurate (C-index = 0.921), reliable (pHosmer-Lemeshow = 0.733) and consistent in the bootstrap sensitivity analysis. No significant association was detected between TAB result and number of days of previous systemic corticosteroid treatment (p = 0.146). However, an association was observed between TAB result and the total accumulated dose of previous systemic corticotherapy (p = 0.043). Exhaustive anamnesis and clinical examination remain of paramount importance in the diagnosis of GCA. To improve the yield of TAB, it should be performed specially in older patients with GCA-compatible clinic. TAB could be avoided in patients with an isolated elevation of acute phase reactants, without GCA-compatible clinic. © 2012 The

  12. 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

  13. Multicenter case-control study protocol of pneumonia etiology in children: Global Approach to Biological Research, Infectious diseases and Epidemics in Low-income countries (GABRIEL network).

    PubMed

    Picot, Valentina Sanchez; Bénet, Thomas; Messaoudi, Melina; Telles, Jean-Noël; Chou, Monidarin; Eap, Tekchheng; Wang, Jianwei; Shen, Kunling; Pape, Jean-William; Rouzier, Vanessa; Awasthi, Shally; Pandey, Nitin; Bavdekar, Ashish; Sanghvi, Sonali; Robinson, Annick; Contamin, Bénédicte; Hoffmann, Jonathan; Sylla, Maryam; Diallo, Souleymane; Nymadawa, Pagbajabyn; Dash-Yandag, Budragchaagiin; Russomando, Graciela; Basualdo, Wilma; Siqueira, Marilda M; Barreto, Patricia; Komurian-Pradel, Florence; Vernet, Guy; Endtz, Hubert; Vanhems, Philippe; Paranhos-Baccalà, Gláucia

    2014-12-10

    Data on the etiologies of pneumonia among children are inadequate, especially in developing countries. The principal objective is to undertake a multicenter incident case-control study of <5-year-old children hospitalized with pneumonia in developing and emerging countries, aiming to identify the causative agents involved in pneumonia while assessing individual and microbial factors associated with the risk of severe pneumonia. A multicenter case-control study, based on the GABRIEL network, is ongoing. Ten study sites are located in 9 countries over 3 continents: Brazil, Cambodia, China, Haiti, India, Madagascar, Mali, Mongolia, and Paraguay. At least 1,000 incident cases and 1,000 controls will be enrolled and matched for age and date. Cases are hospitalized children <5 years with radiologically confirmed pneumonia, and the controls are children without any features suggestive of pneumonia. Respiratory specimens are collected from all enrolled subjects to identify 19 viruses and 5 bacteria. Whole blood from pneumonia cases is being tested for 3 major bacteria. S. pneumoniae-positive specimens are serotyped. Urine samples from cases only are tested for detection of antimicrobial activity. The association between procalcitonin, C-reactive protein and pathogens is being evaluated. A discovery platform will enable pathogen identification in undiagnosed samples. This multicenter study will provide descriptive results for better understanding of pathogens responsible for pneumonia among children in developing countries. The identification of determinants related to microorganisms associated with pneumonia and its severity should facilitate treatment and prevention.

  14. Autologous Skin Cell Spray for Massive Soft Tissue War Injuries: A Prospective, Case-Control, Multicenter Trial

    DTIC Science & Technology

    2015-01-01

    both WRNMMC (45) and UPITT (21), male or female, ages 18 years of age and older with wounds requiring skin grafts will be asked to participate...AD______________ AWARD NUMBER: W81XWH-13-2-0031 TITLE: Autologous Skin Cell Spray for Massive Soft Tissue War Injuries: A Prospective, Case...DATES COVERED 15Mar2013-31Oct2014 4. TITLE AND SUBTITLE Autologous Skin Cell Spray for Massive Soft Tissue War Injuries: A Prospective, Case-Control

  15. Lack of association of CASC8 rs1447295 with colorectal cancer in Iranian population: A multicenter case-control study.

    PubMed

    Haerian, Monir Sadat; Haerian, Batoul Sadat; Molanaei, Saadat; Kosari, Farid; Sabeti, Shahram; Bidari-Zerehpoosh, Farahnaz; Abdolali, Ebrahim

    2017-11-15

    Several studies reported the potential role of the rs1447295 polymorphism in susceptibility to cancer. This variant located in the cancer susceptibility candidate 8 (CASC8) is a long noncoding RNA (lnRNA) gene and does not code protein. LnRNA transcripts play a potential regulatory role in the expression of key genes involved in multiple cellular pathways, including cell cycle, pluripotency, and immune response. The aim of this study is to evaluate this association with colorectal cancer (CRC) in a large case-control study of the Iranian population. After extraction of genomic DNA by the standard protocols, the rs1447295 was genotyped in 2416 subjects (46% patients). Results of this case-control demonstrated no significant association between the rs1447295 polymorphism and risk of CRC or its characteristics under allele or alternative genotype models. In conclusion, it is unlikely that the rs1447295 polymorphism is a risk variant for the development of CRC in Iranian population. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Characterizing restless legs syndrome and leg motor restlessness in patients with Parkinson's disease: A multicenter case-controlled study.

    PubMed

    Suzuki, Keisuke; Okuma, Yasuyuki; Uchiyama, Tomoyuki; Miyamoto, Masayuki; Sakakibara, Ryuji; Shimo, Yasushi; Hattori, Nobutaka; Kuwabara, Satoshi; Yamamoto, Toshimasa; Kaji, Yoshiaki; Hirano, Shigeki; Numao, Ayaka; Hirata, Koichi

    2017-08-14

    We investigated the prevalence and impact of restless legs syndrome (RLS) and leg motor restlessness (LMR) in patients with Parkinson's disease (PD) in a multicenter study. A total of 436 PD patients and 401 age- and sex-matched controls were included in this study. RLS was diagnosed based on four essential features. LMR was diagnosed when a participant exhibited the urge to move his or her legs but did not meet the four essential features of RLS. The RLS prevalence did not differ between PD patients and controls (3.4% vs. 2.7%), while LMR prevalence was significantly higher in PD patients than in controls (12.8% vs. 4.5%). PD patients with RLS or LMR had a higher prevalence of excessive daytime sleepiness (EDS) (50.7%, vs. 6.9%), probable REM sleep behavior disorder (38.0% vs. 3.4%) and PD-related sleep problems (49.3% vs. 20.7%) than controls with RLS or LMR. RLS/LMR preceding PD onset was related to an older age of PD onset. Our study revealed an increased prevalence of LMR but not RLS in PD patients. LMR could be an early manifestation of PD; however, whether LMR is within the range of RLS or whether LMR and RLS constitute different entities in PD requires further studies. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Efficacy of sublingual specific immunotherapy in intermittent and persistent allergic rhinitis in children: an observational case-control study on 171 patients. The EFESO-children multicenter trial.

    PubMed

    Acquistapace, Franca; Agostinis, Fabio; Castella, Vincenzo; Kantar, Ahmad; Novembre, Elio; Perrone, Maria Rosaria; Pietrasanta, Michele; Sambugaro, Renato; Milani, Massimo

    2009-11-01

    Sublingual-specific immunotherapy (SLIT) is considered as a valid treatment of respiratory allergies. However, there are few data on large sample size regarding its clinical role in 'real life' in term of reduction of symptoms, rescue medications and prevention of asthma in patients suffering from allergic rhinitis (AR) especially in children. We performed a multicenter, case-control study to evaluate the effect of SLIT in children (age 6-18 yr) with intermittent or persistent AR. 171 children (27% girls and 73% boys) with AR due to seasonal or perennial allergens were enrolled in a multicenter case-control study. Cases (n = 90) were defined as patients with intermittent (64%) or persistent (36%) AR who were treated for at least two consecutive years with specific SLIT with the related allergen extracts (SLITone ALK-Abellò). Controls (n = 81) were defined as sex-age- and type of allergen matched AR children who were never treated with specific immunotherapy and had no asthmatic symptoms at the beginning of observation period. Main outcomes of the study were the rhinoconjunctivitis symptom score (SS) (sneezing, rhinorrea, nasal itch, congestion, ocular itch and watery eyes) with a ranging scale from 0 (=no symptoms) to 3 (=severe symptoms) and the medication score (MS) evaluating symptomatic drug intake (antihystamine and inhaled corticosteroids). SS and MS were evaluated at the end of the observational period in relation with the period, considering the last 12 months, in which patients suffered the highest symptoms levels (i.e., peak of relevant pollen season (seasonal AR) or during the period of maximum allergen exposure in case of perennial AR). Secondary outcome of the study was the development of asthma symptoms during the observation period. SS (mean +/- SD) was 4.5 +/- 2.5 in cases and 9.0 +/- 3.0 in controls (-50%) (p = 0.0001). MS (mean +/- SD) was 2.5 +/- 1.9 and 3.6 +/- 2.1 in the case and control groups, respectively (-31%) (p = 0.0001). At the end of

  18. Pre-Illness Isoflavone Consumption and Disease Risk of Ulcerative Colitis: A Multicenter Case-Control Study in Japan

    PubMed Central

    Ohfuji, Satoko; Fukushima, Wakaba; Watanabe, Kenji; Sasaki, Satoshi; Yamagami, Hirokazu; Nagahori, Masakazu; Watanabe, Mamoru; Hirota, Yoshio

    2014-01-01

    Introduction Previous studies have suggested that estrogens play a role in the development of ulcerative colitis (UC). Because isoflavones have a similar structure to 17β-estradiol, dietary consumption of isoflavones may have similar influences on the development of UC. We examined the association between pre-illness isoflavone consumption and the risk of UC. Materials and Methods We conducted a hospital-based case control study, and compared the dietary habits of 126 newly diagnosed UC cases with those of 170 age- and gender-matched hospital controls. Information on dietary factors was collected using a self-administered diet history questionnaire. To consider potential changes in dietary habits due to disease symptoms, the habits were assessed separately during the previous 1 month and at 1 year before the recruitment. Results In the assessment of dietary habits during the previous 1 month, the highest tertile of isoflavone consumption revealed an increased odds ratio (OR) for UC (OR = 2.79; 95% confidence interval (CI), 1.39–5.59; Trend P = 0.004). A significant association was also observed for the dietary assessment at 1 year before, when most UC cases had not yet experienced their first disease symptoms (OR = 2.06; 95% CI, 1.05–4.04; Trend P = 0.04). Associations were more pronounced in females (OR in highest tertile of isoflavone consumption at 1 year before = 4.76; 95% CI, 1.30–17.5; Trend P = 0.02) but were obscured in males (corresponding OR = 1.21; 95% CI, 0.49–3.01; Trend P = 0.63). Conclusions Dietary isoflavone consumption may be associated with an increased risk of UC, particularly in females. Prospective cohort studies are warranted to confirm these findings. PMID:25314032

  19. Risk factors for hepatocellular carcinoma in cirrhosis due to nonalcoholic fatty liver disease: A multicenter, case-control study

    PubMed Central

    Corey, Kathleen E; Gawrieh, Samer; deLemos, Andrew S; Zheng, Hui; Scanga, Andrew E; Haglund, Jennifer W; Sanchez, Jorge; Danford, Christopher J; Comerford, Megan; Bossi, Krista; Munir, Samina; Chalasani, Naga; Wattacheril, Julia

    2017-01-01

    AIM To identify risk factors associated with hepatocellular carcinoma (HCC), describe tumor characteristics and treatments pursed for a cohort of individuals with nonalcoholic steatohepatitis (NASH) cirrhosis. METHODS We conducted a retrospective case-control study of a well-characterized cohort of patients among five liver transplant centers with NASH cirrhosis with (cases) and without HCC (controls). RESULTS Ninety-four cases and 150 controls were included. Cases were significantly more likely to be male than controls (67% vs 45%, P < 0.001) and of older age (61.9 years vs 58 years, P = 0.002). In addition, cases were more likely to have had complications of end stage liver disease (83% vs 71%, P = 0.032). On multivariate analysis, the strongest association with the presence of HCC were male gender (OR 4.3, 95%CI: 1.83-10.3, P = 0.001) and age (OR = 1.082, 95%CI: 1.03-1.13, P = 0.001). Hispanic ethnicity was associated with a decreased prevalence of HCC (OR = 0.3, 95%CI: 0.09-0.994, P = 0.048). HCC was predominantly in the form of a single lesion with regional lymph node(s) and distant metastasis in only 2.6% and 6.3%, respectively. Fifty-nine point three percent of individuals with HCC underwent locoregional therapy and 61.5% underwent liver transplantation for HCC. CONCLUSION Male gender, increased age and non-Hispanic ethnicity are associated with HCC in NASH cirrhosis. NASH cirrhosis associated HCC in this cohort was characterized by early stage disease at diagnosis and treatment with locoregional therapy and transplant. PMID:28321274

  20. Nutritional and genetic determinants of vitamin B and homocysteine metabolisms in neural tube defects: a multicenter case-control study.

    PubMed

    Candito, Mirande; Rivet, Romain; Herbeth, Bernard; Boisson, Catherine; Rudigoz, René-Charles; Luton, Dominique; Journel, Hubert; Oury, Jean-François; Roux, François; Saura, Robert; Vernhet, Isabelle; Gaucherand, Pascal; Muller, Françoise; Guidicelli, Béatrice; Heckenroth, Hélène; Poulain, Patrice; Blayau, Martine; Francannet, Christine; Roszyk, Laurence; Brustié, Cécile; Staccini, Pascal; Gérard, Philippe; Fillion-Emery, Nathalie; Guéant-Rodriguez, Rosa-Maria; Van Obberghen, Emmanuel; Guéant, Jean-Louis

    2008-05-01

    Neural tube defects (NTDs) are severe congenital malformations due to failure of neural tube formation in early pregnancy. The proof that folic acid prevents NTDs raises the question of whether other parts of homocysteine (Hcy) metabolism may affect rates of NTDs. This French case-control study covered: 77 women aged 17-42 years sampled prior to elective abortion for a severe NTDs (cases) and 61 women aged 20-43 years with a normal pregnancy. Plasma and erythrocyte folate, plasma B6, B12 and Hcy were tested as five polymorphisms MTHFR 677 C --> T, MTHFR 1298 A --> C, MTR 2756 A --> G, MTTR 66 A --> G and TCN2 776 C --> G. Cases had significantly lower erythrocyte folate, plasma folate, B12 and B6 concentrations than the controls, and higher Hcy concentration. The odds ratio was 2.15 (95% CI: 1.00-4.59) for women with the MTRR 66 A --> G allele and it was decreased for mothers carrying the MTHFR 1298 A --> C allele. In multivariate analysis, only the erythrocyte folate concentration (P = 0.005) and plasma B6 concentration (P = 0.020) were predictors. Red cell folate is the main determinant of NTDs in France. Folic acid supplement or flour fortification would prevent most cases. Increased consumption of vitamins B12 and B6 could contribute to the prevention of NTDs. Genetic polymorphisms played only a small role. Until folic acid fortification becomes mandatory, all women of reproductive age should consume folic acid in a multivitamin that also contains B12 and B6.

  1. Association between levonorgestrel emergency contraception and the risk of ectopic pregnancy: a multicenter case-control study

    PubMed Central

    Zhang, Jian; Li, Cheng; Zhao, Wei-Hong; Xi, Xiaowei; Cao, Shu-Jun; Ping, Hua; Qin, Guo-Juan; Cheng, Linan; Huang, He-Feng

    2015-01-01

    Cases of ectopic pregnancy (EP) following levonorgestrel emergency contraception (LNG-EC) failure have been reported continuously, but whether there is an association between EP risk and LNG-EC is unclear. We concluded a case-control study to explore this association by recruiting 2,411 EP patients as case group, and 2,416 women with intrauterine pregnancy and 2,419 non-pregnant women as control groups. Odds ratios (ORs) and their 95% confidential intervals (CIs) were calculated and adjusted for potential confounding factors. Previous use of LNG-EC was not correlated with the EP. Compared to women who did not use contraceptives, current use of LNG-EC reduced the risk for intrauterine pregnancy (Adjusted OR [AOR] = 0.20, 95%CI: 0.14–0.27), but did not increase the risk for EP (AOR2 = 1.04, 95%CI: 0.76–1.42). Furthermore, compared to women who did not have further act of intercourse, women with unprotected further act of intercourse were at a higher risk of EP (AOR1 = 2.35, 95%CI: 1.17–4.71), and women with repeated use of LNG-EC for further intercourse during the same cycle was also associated with a higher risk for EP (AOR1 = 3.08, 95%CI: 1.09–8.71; AOR2 = 2.49, 95%CI: 1.00–6.19). A better understanding of the risk of EP following LNG-EC failure can optimize LNG-EC use and thus reduce the risk of EP. PMID:25674909

  2. Risk factors, clinical features and outcomes of visceral leishmaniasis in solid-organ transplant recipients: a retrospective multicenter case-control study.

    PubMed

    Clemente, W; Vidal, E; Girão, E; Ramos, A S D; Govedic, F; Merino, E; Muñoz, P; Sabé, N; Cervera, C; Cota, G F; Cordero, E; Mena, A; Montejo, M; López-Medrano, F; Aguado, J M; Fernandes, P; Valerio, M; Carratalá, J; Moreno, A; Oliveira, J; Mourão, P H O; Torre-Cisneros, J

    2015-01-01

    Visceral leishmaniasis (VL) is a rare disease in solid-organ transplant (SOT) recipients. Therefore, little is known about the risk factors and disease behavior in the transplant setting. This multicenter, matched case-control study (1:2 ratio) was designed to determine the risk factors, clinical features and outcomes of VL among this population. Control and case subjects were matched by center, transplant type and timing. Thirty-six VL cases were identified among 25 139 SOT recipients (0.1%). VL occurred 5.7-fold more frequently in Brazil than in Spain, presenting a median time of 11 months after transplantation. High-dose prednisone in the preceding 6 months was associated with VL. Patients were diagnosed over 1 month after symptom onset in 25% of cases. Thirty-one patients (86%) were febrile upon diagnosis, 81% exhibited visceromegaly and 47% showed pancytopenia. Concomitant infection was common. Parasites were identified in 89% of patients; the remaining patients were diagnosed by serology. The majority of the patients received amphotericin B. Relapses occurred in 25.7% of cases, and the crude mortality rate was 2.8%. VL after SOT is related to the VL prevalence in the general population. Delayed diagnosis frequently occurs. Liposomal amphotericin is the most commonly used therapy; mortality is low, although relapses are common.

  3. Is there an association between prior anti-inflammatory drug exposure and occurrence of peritonsillar abscess (PTA)? A national multicenter prospective observational case-control study.

    PubMed

    Lepelletier, D; Pinaud, V; Le Conte, P; Bourigault, C; Asseray, N; Ballereau, F; Caillon, J; Ferron, C; Righini, C; Batard, E; Potel, G

    2017-01-01

    The aim of this study was to evaluate whether recent systemic anti-inflammatory agents (AIAs) exposure in patients with sore throat managed with or without antibiotic therapy influenced the risk of peritonsillar abscess (PTA). We conducted a multicenter case-control study in 13 French university hospitals in 2009-2012 comparing patients admitted with PTA to matched controls: patients with sore throat but without PTA who were followed up for 10 days after visiting their primary-care physician. In the multivariate stepwise logistic regression model comparing 120 cases with PTA to 143 controls, factors significantly associated with PTA were male gender (odds ratio [OR], 2.0; p = 0.03), smoking (OR, 2.0; p = 0.03), and prior self-medication with systemic AIAs (OR, 3.5; p = 0.01). Topical treatment was associated with significant protection against PTA (OR, 0.3; p < 0.001). In conclusion, self-medication with systemic AIAs appears to be an independent factor associated with the occurrence of PTA. This is an important message as non-steroidal AIAs access is favored by their over-counter availability in pharmacies. This finding must be interpreted with caution due to the study design and a prospective, randomized study is needed to substantiate these possible causal risk factors.

  4. Physical workload and accelerated occurrence of lumbar spine diseases: risk and rate advancement periods in a German multicenter case-control study.

    PubMed

    Seidler, Andreas; Euler, Ulrike; Bolm-Audorff, Ulrich; Ellegast, Rolf; Grifka, Joachim; Haerting, Johannes; Jäger, Matthias; Michaelis, Martina; Kuss, Oliver

    2011-01-01

    In a German multicenter case-control study of lumbar disc diseases, we calculated risk and rate advancement periods (RAP) for physical workload. Patients aged 25-70 years with clinically and radiologically verified lumbar disc herniation (286 males, 278 females) or symptomatic lumbar disc narrowing (145 males, 206 females) were compared with population control subjects (453 males and 448 females). For this analysis, all manual handling of objects of about ≥5 kg and postures with trunk inclination of ≥20 °, as assessed by technical experts, were included in the calculation of cumulative lumbar load, determined by biomechanical model calculations. Logistic regression analysis was applied to calculate RAP, adjusted for region. We found a steep positive dose-response relationship between age and lumbar disc narrowing among men as well as women; however, we did not find a monotonic increase in lumbar disc herniation risk with age. As a monotonic increase in disease risk with age constitutes a fundamental assumption underlying the RAP concept, we restricted our RAP analysis to cases with symptomatic lumbar disc narrowing. Among men, there was a positive dose-response relationship between the cumulative lumbar load and the acceleration of lumbar disc narrowing. In the highest exposure category, a RAP of 28.0 years [95% confidence interval (95% CI) 9.7-46.3 years] was found. Among women, the RAP was 8.8 years (95% CI 2.4-15.2 years) in the highest exposure category. This study emphasizes the conceptual importance of risk acceleration - causation not only comprises the occurrence of a disease (that without a specific exposure would not have occurred at all) but also the accelerated occurrence of a disease (that without exposure would have occurred later in life).

  5. Microorganisms Associated With Pneumonia in Children <5 Years of Age in Developing and Emerging Countries: The GABRIEL Pneumonia Multicenter, Prospective, Case-Control Study.

    PubMed

    Bénet, Thomas; Sánchez Picot, Valentina; Messaoudi, Mélina; Chou, Monidarin; Eap, Tekchheng; Wang, Jianwei; Shen, Kunling; Pape, Jean-William; Rouzier, Vanessa; Awasthi, Shally; Pandey, Nitin; Bavdekar, Ashish; Sanghavi, Sonali; Robinson, Annick; Rakoto-Andrianarivelo, Mala; Sylla, Maryam; Diallo, Souleymane; Nymadawa, Pagbajabyn; Naranbat, Nymadawaagiin; Russomando, Graciela; Basualdo, Wilma; Komurian-Pradel, Florence; Endtz, Hubert; Vanhems, Philippe; Paranhos-Baccalà, Gláucia

    2017-06-12

    Pneumonia, the leading infectious cause of child mortality globally, mainly afflicts developing countries. This prospective observational study aimed to assess the microorganisms associated with pneumonia in children aged <5 years in developing and emerging countries. A multicenter, case-control study by the GABRIEL (Global Approach to Biological Research, Infectious diseases and Epidemics in Low-income countries) network was conducted between 2010 and 2014 in Cambodia, China, Haiti, India (2 sites), Madagascar, Mali, Mongolia, and Paraguay. Cases were hospitalized children with radiologically confirmed pneumonia; controls were children from the same setting without any features suggestive of pneumonia. Nasopharyngeal swabs were collected from all subjects; 19 viruses and 5 bacteria were identified by reverse-transcription polymerase chain reaction. Associations between microorganisms and pneumonia were quantified by calculating the adjusted population attributable fraction (aPAF) after multivariate logistic regression analysis adjusted for sex, age, time period, other pathogens, and site. Overall, 888 cases and 870 controls were analyzed; ≥1 microorganism was detected in respiratory samples in 93.0% of cases and 74.4% of controls (P < .001). Streptococcus pneumoniae, Mycoplasma pneumoniae, human metapneumovirus, rhinovirus, respiratory syncytial virus (RSV), parainfluenza virus 1, 3, and 4, and influenza virus A and B were independently associated with pneumonia; aPAF was 42.2% (95% confidence interval [CI], 35.5%-48.2%) for S. pneumoniae, 18.2% (95% CI, 17.4%-19.0%) for RSV, and 11.2% (95% CI, 7.5%-14.7%) for rhinovirus. Streptococcus pneumoniae, RSV, and rhinovirus may be the major microorganisms associated with pneumonia infections in children <5 years of age from developing and emerging countries. Increasing S. pneumoniae vaccination coverage may substantially reduce the burden of pneumonia among children in developing countries.

  6. 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

  7. Retrospective multicenter matched case-control study on the risk factors for narcolepsy with special focus on vaccinations (including pandemic influenza vaccination) and infections in Germany.

    PubMed

    Oberle, Doris; Pavel, Jutta; Mayer, Geert; Geisler, Peter; Keller-Stanislawski, Brigitte

    2017-06-01

    Studies associate pandemic influenza vaccination with narcolepsy. In Germany, a retrospective, multicenter, matched case-control study was performed to identify risk factors for narcolepsy, particularly regarding vaccinations (seasonal and pandemic influenza vaccination) and infections (seasonal and pandemic influenza) and to quantify the detected risks. Patients with excessive daytime sleepiness who had been referred to a sleep center between April 2009 and December 2012 for multiple sleep latency test (MSLT) were eligible. Case report forms were validated according to the criteria for narcolepsy defined by the Brighton Collaboration (BC). Confirmed cases of narcolepsy (BC level of diagnostic certainty 1-4a) were matched with population-based controls by year of birth, gender, and place of residence. A second control group was established including patients in whom narcolepsy was definitely excluded (test-negative controls). A total of 103 validated cases of narcolepsy were matched with 264 population-based controls. The second control group included 29 test-negative controls. A significantly increased odd ratio (OR) to develop narcolepsy (crude OR [cOR] = 3.9, 95% confidence interval [CI] = 1.8-8.5; adjusted OR [aOR] = 4.5, 95% CI = 2.0-9.9) was detected in individuals immunized with pandemic influenza A/H1N1/v vaccine prior to symptoms onset as compared to nonvaccinated individuals. Using test-negative controls, in individuals immunized with pandemic influenza A/H1N1/v vaccine prior to symptoms onset, a nonsignificantly increased OR of narcolepsy was detected when compared to nonvaccinated individuals (whole study population, BC levels 1-4a: cOR = 1.9, 95% CI = 0.5-6.9; aOR = 1.8, 95% CI = 0.3-10.1). The findings of this study support an increased risk for narcolepsy after immunization with pandemic influenza A/H1N1/v vaccine. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Burden and aetiology of diarrhoeal disease in infants and young children in developing countries (the Global Enteric Multicenter Study, GEMS): a prospective, case-control study.

    PubMed

    Kotloff, Karen L; Nataro, James P; Blackwelder, William C; Nasrin, Dilruba; Farag, Tamer H; Panchalingam, Sandra; Wu, Yukun; Sow, Samba O; Sur, Dipika; Breiman, Robert F; Faruque, Abu Sg; Zaidi, Anita Km; Saha, Debasish; Alonso, Pedro L; Tamboura, Boubou; Sanogo, Doh; Onwuchekwa, Uma; Manna, Byomkesh; Ramamurthy, Thandavarayan; Kanungo, Suman; Ochieng, John B; Omore, Richard; Oundo, Joseph O; Hossain, Anowar; Das, Sumon K; Ahmed, Shahnawaz; Qureshi, Shahida; Quadri, Farheen; Adegbola, Richard A; Antonio, Martin; Hossain, M Jahangir; Akinsola, Adebayo; Mandomando, Inacio; Nhampossa, Tacilta; Acácio, Sozinho; Biswas, Kousick; O'Reilly, Ciara E; Mintz, Eric D; Berkeley, Lynette Y; Muhsen, Khitam; Sommerfelt, Halvor; Robins-Browne, Roy M; Levine, Myron M

    2013-07-20

    Diarrhoeal diseases cause illness and death among children younger than 5 years in low-income countries. We designed the Global Enteric Multicenter Study (GEMS) to identify the aetiology and population-based burden of paediatric diarrhoeal disease in sub-Saharan Africa and south Asia. The GEMS is a 3-year, prospective, age-stratified, matched case-control study of moderate-to-severe diarrhoea in children aged 0-59 months residing in censused populations at four sites in Africa and three in Asia. We recruited children with moderate-to-severe diarrhoea seeking care at health centres along with one to three randomly selected matched community control children without diarrhoea. From patients with moderate-to-severe diarrhoea and controls, we obtained clinical and epidemiological data, anthropometric measurements, and a faecal sample to identify enteropathogens at enrolment; one follow-up home visit was made about 60 days later to ascertain vital status, clinical outcome, and interval growth. We enrolled 9439 children with moderate-to-severe diarrhoea and 13,129 control children without diarrhoea. By analysing adjusted population attributable fractions, most attributable cases of moderate-to-severe diarrhoea were due to four pathogens: rotavirus, Cryptosporidium, enterotoxigenic Escherichia coli producing heat-stable toxin (ST-ETEC; with or without co-expression of heat-labile enterotoxin), and Shigella. Other pathogens were important in selected sites (eg, Aeromonas, Vibrio cholerae O1, Campylobacter jejuni). Odds of dying during follow-up were 8·5-fold higher in patients with moderate-to-severe diarrhoea than in controls (odd ratio 8·5, 95% CI 5·8-12·5, p<0·0001); most deaths (167 [87·9%]) occurred during the first 2 years of life. Pathogens associated with increased risk of case death were ST-ETEC (hazard ratio [HR] 1·9; 0·99-3·5) and typical enteropathogenic E coli (HR 2·6; 1·6-4·1) in infants aged 0-11 months, and Cryptosporidium (HR 2·3; 1·3-4·3

  9. Investigation of occupational and environmental causes of respiratory cancers (ICARE): a multicenter, population-based case-control study in France

    PubMed Central

    2011-01-01

    Background Occupational causes of respiratory cancers need to be further investigated: the role of occupational exposures in the aetiology of head and neck cancers remains largely unknown, and there are still substantial uncertainties for a number of suspected lung carcinogens. The main objective of the study is to examine occupational risk factors for lung and head and neck cancers. Methods/design ICARE is a multi-center, population-based case-control study, which included a group of 2926 lung cancer cases, a group of 2415 head and neck cancer cases, and a common control group of 3555 subjects. Incident cases were identified in collaboration with cancer registries, in 10 geographical areas. The control group was a random sample of the population of these areas, with a distribution by sex and age comparable to that of the cases, and a distribution by socioeconomic status comparable to that of the population. Subjects were interviewed face to face, using a standardized questionnaire collecting particularly information on tobacco and alcohol consumption, residential history and a detailed description of occupational history. Biological samples were also collected from study subjects. The main occupational exposures of interest are asbestos, man-made mineral fibers, formaldehyde, polycyclic aromatic hydrocarbons, chromium and nickel compounds, arsenic, wood dust, textile dust, solvents, strong acids, cutting fluids, silica, diesel fumes, welding fumes. The complete list of exposures of interest includes more than 60 substances. Occupational exposure assessment will use several complementary methods: case-by-case evaluation of exposure by experts; development and use of algorithms to assess exposure from the questionnaires; application of job-exposure matrices. Discussion The large number of subjects should allow to uncover exposures associated with moderate increase in risks, and to evaluate risks associated with infrequent or widely dispersed exposures. It will be

  10. Clinical predictors of methicillin-resistant Staphylococcus aureus in nosocomial and healthcare-associated pneumonia: a multicenter, matched case-control study.

    PubMed

    Torre-Cisneros, J; Natera, C; Mesa, F; Trikic, M; Rodríguez-Baño, J

    2017-09-08

    The situations in which coverage for methicillin-resistant Staphylococcus aureus (MRSA) in the empirical treatment of nosocomial pneumonia (NP) or severe healthcare-associated pneumonia (HCAP) is needed are poorly defined, particularly outside intensive care units (ICUs). Our aim was to characterize if the risk of MRSA NP/HCAP can be defined by clinical variables. We designed an observational, retrospective, multicenter, case-control study to analyze the association between defined clinical variables and risk of MRSA NP/HCAP in non-ICU patients using conditional multivariable logistic regression. Cases and controls (1:2) with microbiological diagnosis were included. Controls were matched for hospital, type of pneumonia (NP or HCAP), and date of isolation. A total of 140 cases (77 NP and 63 HCAP) and 280 controls were studied. The variables associated with the risk of MRSA pneumonia were: (i) respiratory infection/colonization caused by MRSA in the previous year [odds ratio (OR) 14.81, 95% confidence interval (CI) 4.13-53.13, p < 0.001]; (ii) hospitalization in the previous 90 days (OR 2.41, 95% CI 1.21-4.81, p = 0.012); and (iii) age (OR 1.02, 95% CI 1.001-1.05, p = 0.040). The area under the receiver operating characteristic (ROC) curve for the multivariable model was 0.72 (95% CI 0.66-0.78). The multivariate model had a sensitivity of 74.5% (95% CI 65.3-83.6), a specificity of 63.3% (95% CI 56.0-70.6), a positive predictive value of 52.5% (95% CI 43.9-61.2), and a negative predictive value of 82.0% (95% CI 75.3-88.8) for the observed data. Clinical predictors of MRSA NP/HCAP can be used to define a low-risk population in whom coverage against MRSA may not be needed.

  11. Location in the right hemi-colon is an independent risk factor for delayed post-polypectomy hemorrhage: a multi-center case-control study.

    PubMed

    Buddingh, K Tim; Herngreen, Thomas; Haringsma, Jelle; van der Zwet, Wil C; Vleggaar, Frank P; Breumelhof, Ronald; Ter Borg, Frank

    2011-06-01

    Delayed hemorrhage is an infrequent, but serious complication of colonoscopic polypectomy. Large size is the only polyp-related factor that has been unequivocally proven to increase the risk of delayed bleeding. It has been suggested that location in the right hemi-colon is also a risk factor. The objective of this study was to determine whether polyp location is an independent risk factor for delayed post-polypectomy hemorrhage. A retrospective case-control study was conducted in two university hospitals and two community hospitals. Thirty-nine cases and 117 controls were identified. In multivariate analysis, size and location were found to be independent polyp-related risk factors for delayed type hemorrhage. The risk increased by 13% for every 1 mm increase in polyp diameter (odds ratio (OR) 1.13, 95% confidence interval (CI) 1.05-1.20, P<0.001). Polyps located in the right hemi-colon had an OR of 4.67 (1.88-11.61, P=0.001) for delayed hemorrhage. Polyps in the cecum seemed to be especially at high risk in univariate analysis (OR 13.82, 95% CI 2.66-71.73), but this could not be assessed in multivariate analysis as the number of cases was too small. Polyp type (sessile or pedunculated) was not a risk factor. Polyp location in the right hemi-colon seems to be an independent and substantial risk factor for delayed post-polypectomy hemorrhage. A low threshold for preventive hemostatic measures is advised when removing polyps from this region.

  12. 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. Copyright © 2015 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  13. The Karachi intracranial stenosis study (KISS) Protocol: An urban multicenter case-control investigation reporting the clinical, radiologic and biochemical associations of intracranial stenosis in Pakistan

    PubMed Central

    Kamal, Ayeesha Kamran; Taj, Fawad; Junaidi, Babar; Rasheed, Asif; Zaidi, Moazzam; Murtaza, Muhammed; Iqbal, Naved; Hashmat, Fahad; Alam, Syed Vaqas; Saleem, Uzma; Waheed, Shahan; Bansari, Lajpat; Shah, Nabi; Samuel, Maria; Yameen, Madiha; Naz, Sobia; Khan, Farrukh Shahab; Ahmed, Naveeduddin; Mahmood, Khalid; Sheikh, Niaz; Makki, Karim Ullah; Ahmed, Muhammad Masroor; Memon, Abdul Rauf; Wasay, Mohammad; Syed, Nadir Ali; Khealani, Bhojo; Frossard, Philippe M; Saleheen, Danish

    2009-01-01

    Background Intracranial stenosis is the most common cause of stroke among Asians. It has a poor prognosis with a high rate of recurrence. No effective medical or surgical treatment modality has been developed for the treatment of stroke due to intracranial stenosis. We aim to identify risk factors and biomarkers for intracranial stenosis and to develop techniques such as use of transcranial doppler to help diagnose intracranial stenosis in a cost-effective manner. Methods/Design The Karachi Intracranial Stenosis Study (KISS) is a prospective, observational, case-control study to describe the clinical features and determine the risk factors of patients with stroke due to intracranial stenosis and compare them to those with stroke due to other etiologies as well as to unaffected individuals. We plan to recruit 200 patients with stroke due to intracranial stenosis and two control groups each of 150 matched individuals. The first set of controls will include patients with ischemic stroke that is due to other atherosclerotic mechanisms specifically lacunar and cardioembolic strokes. The second group will consist of stroke free individuals. Standardized interviews will be conducted to determine demographic, medical, social, and behavioral variables along with baseline medications. Mandatory procedures for inclusion in the study are clinical confirmation of stroke by a healthcare professional within 72 hours of onset, 12 lead electrocardiogram, and neuroimaging. In addition, lipid profile, serum glucose, creatinine and HbA1C will be measured in all participants. Ancillary tests will include carotid ultrasound, transcranial doppler and magnetic resonance or computed tomography angiogram to rule out concurrent carotid disease. Echocardiogram and other additional investigations will be performed at these centers at the discretion of the regional physicians. Discussion The results of this study will help inform locally relevant clinical guidelines and effective public health

  14. 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

  15. A multi-center population-based case-control study of ovarian cancer in African-American women: the African American Cancer Epidemiology Study (AACES).

    PubMed

    Schildkraut, Joellen M; Alberg, Anthony J; Bandera, Elisa V; Barnholtz-Sloan, Jill; Bondy, Melissa; Cote, Michelle L; Funkhouser, Ellen; Peters, Edward; Schwartz, Ann G; Terry, Paul; Wallace, Kristin; Akushevich, Lucy; Wang, Frances; Crankshaw, Sydnee; Moorman, Patricia G

    2014-09-22

    Ovarian cancer (OVCA) is the leading cause of death from gynecological cancer, with poorer survival for African American (AA) women compared to whites. However, little is known about risk factors for OVCA in AA. To study the epidemiology of OVCA in this population, we started a collaborative effort in 10 sites in the US. Here we describe the study and highlight the challenges of conducting a study of a lethal disease in a minority population. The African American Cancer Epidemiology Study (AACES) is an ongoing, population-based case-control study of OVCA in AA in 10 geographic locations, aiming to recruit 850 women with invasive epithelial OVCA and 850 controls age- and geographically-matched to cases. Rapid case ascertainment and random-digit-dialing systems are in place to ascertain cases and controls, respectively. A telephone survey focuses on risk factors as well as factors of particular relevance for AAs. Food-frequency questionnaires, follow-up surveys, biospecimens and medical records are also obtained. Current accrual of 403 AA OVCA cases and 639 controls exceeds that of any existing study to date. We observed a high proportion (15%) of deceased non-responders among the cases that in part is explained by advanced stage at diagnosis. A logistic regression model did not support that socio-economic status was a factor in advanced stage at diagnosis. Most risk factor associations were in the expected direction and magnitude. High BMI was associated with ovarian cancer risk, with multivariable adjusted ORs and 95% CIs of 1.50 (0.99-2.27) for obese and 1.27 (0.85- 1.91) for morbidly obese women compared to normal/underweight women. AACES targets a rare tumor in AAs and addresses issues most relevant to this population. The importance of the study is accentuated by the high proportion of OVCA cases ascertained as deceased. Our analyses indicated that obesity, highly prevalent in this population (>60% of the cases), was associated with increased OVCA risk. While

  16. Laparoscopic surgery for colorectal cancer is safe and has survival outcomes similar to those of open surgery in elderly patients with a poor performance status: subanalysis of a large multicenter case-control study in Japan.

    PubMed

    Niitsu, Hiroaki; Hinoi, Takao; Kawaguchi, Yasuo; Ohdan, Hideki; Hasegawa, Hirotoshi; Suzuka, Ichio; Fukunaga, Yosuke; Yamaguchi, Takashi; Endo, Shungo; Tagami, Soichi; Idani, Hitoshi; Ichihara, Takao; Watanabe, Kazuteru; Watanabe, Masahiko

    2016-01-01

    It remains controversial whether open or laparoscopic surgery should be indicated for elderly patients with colorectal cancer and a poor performance status. In those patients aged 80 years or older with Eastern Cooperative Oncology Group performance status score of 2 or greater who received elective surgery for stage 0 to stage III colorectal adenocarcinoma and had no concomitant malignancies and who were enrolled in a multicenter case-control study entitled "Retrospective study of laparoscopic colorectal surgery for elderly patients" that was conducted in Japan between 2003 and 2007, background characteristics and short-term and long-term outcomes for open surgery and laparoscopic surgery were compared. Of the 398 patients included, 295 underwent open surgery and 103 underwent laparoscopic surgery. There were no significant differences in the baseline characteristics between open surgery and laparoscopic surgery patients, except for previous abdominal surgery and TNM stage. The median operation duration was shorter with open surgery (open surgery, 153 min; laparoscopic surgery, 202 min; P < 0.001), and less blood loss occurred with laparoscopic surgery (median open surgery, 109 g; median laparoscopic surgery, 30 g; P < 0.001). An operation duration of 180 min or more (odds ratio, 1.97; 95 % confidence interval, 1.17-3.37; P = 0.011) and selection of laparoscopic surgery (odds ratio, 0.41; 95 % confidence interval, 0.22-0.75; P = 0.003) were statistically significant in the multivariate analysis for postoperative morbidity. Moreover, laparoscopic surgery did not result in an inferior overall survival rate compared with open surgery (log-rank test P = 0.289, 0.278, 0.346, 0.199, for all-stage, stage 0-I, stage II, and stage III disease, respectively). Laparoscopic surgery in elderly colorectal cancer patients with a poor performance status is safe and not inferior to open surgery in terms of overall survival.

  17. 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

    Baker, Kelly K; O'Reilly, Ciara E; Levine, Myron M; Kotloff, Karen L; Nataro, James P; Ayers, Tracy L; Farag, Tamer H; Nasrin, Dilruba; Blackwelder, William C; Wu, Yukun; 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

    2016-05-01

    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. 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 area near the home, soap or ash

  18. 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

  19. Prevalence, incidence estimation, risk factors and characterization of chronic prostatitis/chronic pelvic pain syndrome in urological hospital outpatients in Italy: results of a multicenter case-control observational study.

    PubMed

    Bartoletti, Riccardo; Cai, Tommaso; Mondaini, Nicola; Dinelli, Nicola; Pinzi, Novello; Pavone, Carlo; Gontero, Paolo; Gavazzi, Andrea; Giubilei, Gianluca; Prezioso, Domenico; Mazzoli, Sandra; Boddi, Vieri; Naber, Kurt G

    2007-12-01

    We evaluated the prevalence and estimated the incidence and risk factors of chronic prostatitis/chronic pelvic pain syndrome in urological hospital outpatients in Italy. From January to June 2006 patients from 28 Italian urological centers who were between 25 and 50 years old with symptoms of chronic prostatitis/chronic pelvic pain syndrome were consecutively enrolled in this prospective epidemiological case-control study. A total of 152 subjects of similar age, race and area of origin who were investigated for infertile couples but were otherwise healthy served as controls. All subjects provided a medical history and underwent different symptom scorings, clinical evaluation and microbiological tests. Of 5,540 male urological outpatients 764 with chronic prostatitis/chronic pelvic pain syndrome were enrolled, including 225 (29.4%) at the first presentation and 539 (70.6%) who underwent previous treatment. Thus, the prevalence of the syndrome was 13.8%, while the estimated incidence was 4.5%. Cigarette smoking, a high caloric diet with low fruit and vegetable consumption, constipation, meteorism, slow digestion, a sexual relationship with more than 1 partner and coitus interruptus were more likely in patients with chronic prostatitis/chronic pelvic pain syndrome than in controls (each p <0.001). The syndrome had a negative influence on sexual desire, erectile dysfunction and premature ejaculation (p <0.001). The Meares and Stamey test was positive in 13.3% of patients and in 2.9% of controls. Urethral swabs in patients with a negative Meares and Stamey test were positive for sexually transmitted pathogens in 6%. The prevalence and estimated incidence of chronic prostatitis/chronic pelvic pain syndrome in urological hospital outpatients in Italy are high. The syndrome is closely related to lifestyle, diet, smoking, gastrointestinal or anorectal disease and impaired sexual function.

  20. 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

  1. 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

  2. Case-control studies: basic concepts.

    PubMed

    Vandenbroucke, Jan P; Pearce, Neil

    2012-10-01

    The purpose of this article is to present in elementary mathematical and statistical terms a simple way to quickly and effectively teach and understand case-control studies, as they are commonly done in dynamic populations-without using the rare disease assumption. Our focus is on case-control studies of disease incidence ('incident case-control studies'); we will not consider the situation of case-control studies of prevalent disease, which are published much less frequently.

  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. 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…

  5. Are nested case-control studies biased?

    PubMed Central

    Langholz, Bryan; Richardson, David

    2014-01-01

    It has been recently asserted that the nested case-control study design, in which case-control sets are sampled from cohort risk sets, can introduce bias (“study design bias”) when there are lagged exposures. The bases for this claim include a theoretic and an “empirical evaluation” argument. Both of these arguments are examined and found to be incorrect. Appropriate methods to explore the performance of nested case-control study designs, analysis methods, and compute power and sample size from an existing cohort are described. This empirical evaluation approach relies on simulating case-control outcomes from risk sets in the cohort from which the case-control study is to be performed. Because it is based on the underlying cohort structure, the empirical evaluation can provide an assessment that is tailored to the specific characteristics of the study under consideration. The methods are illustrated using samples from the Colorado Plateau uranium miners cohort. PMID:19289963

  6. Case-control studies in neurosurgery.

    PubMed

    Nesvick, Cody L; Thompson, Clinton J; Boop, Frederick A; Klimo, Paul

    2014-08-01

    Observational studies, such as cohort and case-control studies, are valuable instruments in evidence-based medicine. Case-control studies, in particular, are becoming increasingly popular in the neurosurgical literature due to their low cost and relative ease of execution; however, no one has yet systematically assessed these types of studies for quality in methodology and reporting. The authors performed a literature search using PubMed/MEDLINE to identify all studies that explicitly identified themselves as "case-control" and were published in the JNS Publishing Group journals (Journal of Neurosurgery, Journal of Neurosurgery: Pediatrics, Journal of Neurosurgery: Spine, and Neurosurgical Focus) or Neurosurgery. Each paper was evaluated for 22 descriptive variables and then categorized as having either met or missed the basic definition of a case-control study. All studies that evaluated risk factors for a well-defined outcome were considered true case-control studies. The authors sought to identify key features or phrases that were or were not predictive of a true case-control study. Those papers that satisfied the definition were further evaluated using the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) checklist. The search detected 67 papers that met the inclusion criteria, of which 32 (48%) represented true case-control studies. The frequency of true case-control studies has not changed with time. Use of odds ratios (ORs) and logistic regression (LR) analysis were strong positive predictors of true case-control studies (for odds ratios, OR 15.33 and 95% CI 4.52-51.97; for logistic regression analysis, OR 8.77 and 95% CI 2.69-28.56). Conversely, negative predictors included focus on a procedure/intervention (OR 0.35, 95% CI 0.13-0.998) and use of the word "outcome" in the Results section (OR 0.23, 95% CI 0.082-0.65). After exclusion of nested case-control studies, the negative correlation between focus on a procedure

  7. 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

  8. Bolting multicenter solutions

    NASA Astrophysics Data System (ADS)

    Bena, Iosif; Bossard, Guillaume; Katmadas, Stefanos; Turton, David

    2017-01-01

    We introduce a solvable system of equations that describes non-extremal multicenter solutions to six-dimensional ungauged supergravity coupled to tensor multiplets. The system involves a set of functions on a three-dimensional base metric. We obtain a family of non-extremal axisymmetric solutions that generalize the known multicenter extremal solutions, using a particular base metric that introduces a bolt. We analyze the conditions for regularity, and in doing so we show that this family does not include solutions that contain an extremal black hole and a smooth bolt. We determine the constraints that are necessary to obtain smooth horizonless solutions involving a bolt and an arbitrary number of Gibbons-Hawking centers.

  9. 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

  10. Case-control studies in diabetes. Do they really use a case-control design?

    PubMed

    Ramos, Analía; Mendoza, Lilian Cristina; Rabasa, Fernanda; Bolíbar, Ignasi; Puig, Teresa; Corcoy, Rosa

    2017-07-01

    Studies defined as case-control do not always use this design. We aimed to estimate the frequency of mislabelled case-control studies in published articles in the area of diabetes and to identify the predictors of incorrect labelling. We searched Medline and Web of Science for articles with "diabetes" and "case control" in title and filtered for language (English/Romance) and period (January 2010-December 2014). Inclusion criteria were: (1) statement to use a case-control design in title, (2) to be a final full-length publication and (3) to have original data in the area of diabetes. Three independent reviewers went through titles, looked for full texts and reviewed them. Discrepancies were settled with a fourth reviewer. Expert epidemiologist advice was requested in case of doubt. case-control mislabelling; addressed predictors: publication year, journal impact factor and journal subject. proportion of mislabelled CC articles and assessment of predictors by multivariate logistic regression analysis. We retrieved 362 articles, 251 of them fulfilling inclusion criteria. The proportion of mislabelled CC studies was 43.8% (confidence interval 95% 37.7-50.0%). Most mislabelled studies had a cross-sectional design (82.7%). Predictors of mislabelling were publication year, journal impact factor and journal area. A relevant subset of studies defined as case-control in the area of diabetes correspond to mislabelled cross-sectional studies. Incorrect labelling misleads readers regarding the interpretation of results and the cause-effect hypothesis. Researchers, reviewers and editors should be aware of and commit to settle this issue.

  11. 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

  12. Early pyloric stenosis: a case control study.

    PubMed

    Demian, Marie; Nguyen, Son; Emil, Sherif

    2009-12-01

    Pyloric stenosis (PS) is rare in the first 2 weeks of life, often leading to delays in diagnosis and treatment. We conducted a case control study to delineate the characteristics of patients with early PS (EPS). In addition, we tested the hypothesis that patients with EPS present with a smaller pylorus than older patients. A database of all patients presenting with PS to a children's hospital over a 5-year period (2002-2006) was obtained. Each patient admitted during the first 2 weeks of life (subject) was matched to a patient admitted after 4 weeks of age (control), with the same gender, electrolyte status, and treating surgeon. A single pediatric radiologist, blinded to patient age, reviewed all available ultrasounds retrospectively. Demographic, clinical, diagnostic, therapeutic, and outcome data were compared. During the study period, 278 pyloromyotomies were performed for PS. Sixteen patients (5.8%) presented with EPS between 2 and 14 days of life. EPS patients had a higher prevalence of positive family history (31 vs. 0%, P = 0.043), and breast milk feeding (75 vs. 31%, P = 0.045). Sonographic measurements showed a pylorus that was of significantly less length (17.1 +/- 0.6 vs. 20.5 +/- 0.9 mm, P = 0.006) and muscle thickness (3.5 +/- 0.2 vs. 4.9 +/- 0.2 mm, P < 0.001) in patients with EPS. Hospital stay was significantly longer for EPS patients (4.3 +/- 0.9 vs. 2.0 +/- 0.1 days, P = 0.19). Babies presenting with EPS are more likely to be breast fed and to have a positive family history. EPS is associated with a longer hospital stay. Use of sonographic diagnostic measurements specific to this age group may prevent delays in diagnosis and treatment, and improve outcomes.

  13. The case-control design in veterinary sciences: A survey.

    PubMed

    Cullen, Jonah N; Sargeant, Jan M; Makielski, Kelly M; O'Connor, Annette M

    2016-11-01

    The case-control study design is deceptively simple. However, many design considerations influence the estimated effect measure. An investigation of case-control studies in the human health literature suggested that some of these considerations are not described in reports of case-control studies. Our hypothesis was that the majority of veterinary studies labeled as case-controls would be incident density designs, and many would not interpret the effect measure obtained from those studies as the rate ratio rather than the odds ratio. Reference databases were searched for author-designated case-control studies. A survey of 100 randomly selected studies was conducted to examine the different design options described and estimated effect measures. Of the 100 author-identified case-control studies, 83 assessed an exposure-outcome association and, of those, only 54 (65.1%) sampled the study population based on an outcome and would thus be considered case-control designs. Twelve studies were incidence density designs but none used this terminology. Of the studies that reported an odds ratio as the effect measure, none reported on additional considerations that would have enabled a more interpretable result. This survey indicated many case-control-labeled studies were not case-control designs and among case-control studies, key design aspects were not often described. The absence of information about study design elements and underlying assumptions in case-control studies limits the ability to establish the effect measured by the study and the evidentiary value of the study might be underestimated. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Population-based case-control association studies.

    PubMed

    Hancock, Dana B; Scott, William K

    2012-07-01

    This unit provides an overview of the design and analysis of population-based case-control studies of genetic risk factors for complex disease. Considerations specific to genetic studies are emphasized. The unit reviews basic study designs differentiating case-control studies from others, presents different genetic association strategies (candidate gene, genome-wide association, and high-throughput sequencing), introduces basic methods of statistical analysis for case-control data and approaches to combining case-control studies, and discusses measures of association and impact. Admixed populations, controlling for confounding (including population stratification), consideration of multiple loci and environmental risk factors, and complementary analyses of haplotypes, genes, and pathways are briefly discussed. Readers are referred to basic texts on epidemiology for more details on general conduct of case-control studies.

  15. Environmental and occupational risk factors for progressive supranuclear palsy: Case-control study.

    PubMed

    Litvan, Irene; Lees, Peter S J; Cunningham, Christopher R; Rai, Shesh N; Cambon, Alexander C; Standaert, David G; Marras, Connie; Juncos, Jorge; Riley, David; Reich, Stephen; Hall, Deborah; Kluger, Benzi; Bordelon, Yvette; Shprecher, David R

    2016-05-01

    The cause of progressive supranuclear palsy (PSP) is largely unknown. Based on evidence for impaired mitochondrial activity in PSP, we hypothesized that the disease may be related to exposure to environmental toxins, some of which are mitochondrial inhibitors. This multicenter case-control study included 284 incident PSP cases of 350 cases and 284 age-, sex-, and race-matched controls primarily from the same geographical areas. All subjects were administered standardized interviews to obtain data on demographics, residential history, and lifetime occupational history. An industrial hygienist and a toxicologist unaware of case status assessed occupational histories to estimate past exposure to metals, pesticides, organic solvents, and other chemicals. Cases and controls were similar on demographic factors. In unadjusted analyses, PSP was associated with lower education, lower income, more smoking pack-years, more years of drinking well water, more years living on a farm, more years living 1 mile from an agricultural region, more transportation jobs, and more jobs with exposure to metals in general. However, in adjusted models, only more years of drinking well water was significantly associated with PSP. There was an inverse association with having a college degree. We did not find evidence for a specific causative chemical exposure; higher number of years of drinking well water is a risk factor for PSP. This result remained significant after adjusting for income, smoking, education and occupational exposures. This is the first case-control study to demonstrate PSP is associated with environmental factors. © 2016 International Parkinson and Movement Disorder Society. © 2016 International Parkinson and Movement Disorder Society.

  16. A multicenter case-control study of diagnostic tests for urinary tract infection in the presence of urolithiasis.

    PubMed

    Yilmaz, S; Pekdemir, M; Aksu, N M; Koyuncu, N; Cinar, O; Akpinar, E

    2012-02-01

    Urinary stone disease (USD) alone can cause much morbidity, but when present in conjunction with urinary tract infection, complications and morbidity increase even more. This study investigated the clinical and laboratory findings in patients who had USD with and without infection and evaluated the most suitable diagnostic value for urinary tract infection parameters before urine culture results were available. In a prospective fashion, patients who presented to the emergency department with a complaint of colicky flank pain (with or without hematuria) and who were diagnosed as having urolithiasis with ultrasound were evaluated for 1 year. The gold standard for the diagnosis of urinary tract infection was urine culture. The most suitable diagnostic value for urinary tract infection parameters was determined by receiver operating characteristic (ROC) curves. Logistic regression was used to identify independent variables that predicted a positive urine culture. Of the 192 eligible patients, 177 agreed to participate in the study. Of the clinical and laboratory characteristics analyzed, urine WBC, blood WBC, and fever were significantly different between culture positive and negative patients (p < 0.001, p = 0.04 p = 0.012, respectively). Using ROC curve analysis, pyuria (over 10 WBCs per HPF), fever over 37.9°C, and leucocytosis over 11,300 were the best predictors of a positive culture result. The logistic regression model for leukocytosis >11,300 (OR 2.1), pyuria (OR 2.8), and temperature >37.9°C (OR 3.1) showed a significantly increased risk of having a positive urine culture (correct class 87.9%). While a single physical examination or laboratory finding cannot predict urinary tract infection in USD patients with complete reliability, the presence of pyruria, fever, and leukocytosis significantly increases the odds of a positive urine culture.

  17. Autologous Skin Cell Spray for Massive Soft Tissue War Injuries: A Prospective, Case-Control, Multicenter Trial

    DTIC Science & Technology

    2014-04-01

    extrapolated to complex traumatic civilian injuries that likewise pose significant issues with available autologous skin coverage (e.g. necrotizing ... fasciitis , motor vehicle accidents or other trauma with associated soft tissue avulsion injuries, etc.). Important data on the mechanism of action

  18. 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 below...

  19. Is intravesical instillation of hyaluronic acid and chondroitin sulfate useful in preventing recurrent bacterial cystitis? A multicenter case control analysis.

    PubMed

    Gugliotta, Giorgio; Calagna, Gloria; Adile, Giorgio; Polito, Salvatore; Saitta, Salvatore; Speciale, Patrizia; Palomba, Stefano; Perino, Antonino; Granese, Roberta; Adile, Biagio

    2015-10-01

    Urinary tract infections (UTIs) are common in the female population and, over a lifetime, about half of women have at least one episode of UTI requiring antibiotic therapy. The aim of the current study was to compare two different strategies for preventing recurrent bacterial cystitis: intravesical instillation of hyaluronic acid (HA) plus chondroitin sulfate (CS), and antibiotic prophylaxis with sulfamethoxazole plus trimethoprim. This was a retrospective review of two different cohorts of women affected by recurrent bacterial cystitis. Cases (experimental group) were women who received intravesical instillations of a sterile solution of high concentration of HA + CS in 50 mL water with calcium chloride every week during the 1(st) month and then once monthly for 4 months. The control group included women who received traditional therapy for recurrent cystitis based on daily antibiotic prophylaxis using sulfamethoxazole 200 mg plus trimethoprim 40 mg for 6 weeks. Ninety-eight and 76 patients were treated with experimental and control treatments, respectively. At 12 months after treatment, 69 and 109 UTIs were detected in the experimental and control groups, respectively. The proportion of patients free from UTIs was significantly higher in the experimental than in the control group (36.7% vs. 21.0%; p = 0.03). Experimental treatment was well tolerated and none of the patients stopped it. The intravesical instillation of HA + CS is more effective than long-term antibiotic prophylaxis for preventing recurrent bacterial cystitis. Copyright © 2015. Published by Elsevier B.V.

  20. The association between breast cancer and S100P methylation in peripheral blood by multicenter case-control studies.

    PubMed

    Yang, Rongxi; Stöcker, Sarah; Schott, Sarah; Heil, Jörg; Marme, Frederik; Cuk, Katarina; Chen, Bowang; Golatta, Michael; Zhou, Yan; Sutter, Christian; Wappenschmidt, Barbara; Schmutzler, Rita; Bugert, Peter; Qu, Bin; Bartram, Claus R; Sohn, Christof; Schneeweiss, Andreas; Burwinkel, Barbara

    2017-03-01

    Breast cancer (BC) is the leading cancer in women worldwide. Changes in DNA methylation in peripheral blood could be associated with malignant diseases. Making use of screening results by llumina 27K Methylation Assay, we validated demethylation of five CpG sites of S100P gene in blood cell DNA of BC patients by three independent retrospective studies with subjects from different centers (Validation I: 235 familial BC case and 206 controls, odds ratio per -1% methylation > 1.03, and P < 6.00 × 10-8 for all five CpG sites; Validation II: 189 sporadic BC case and 189 controls, odds ratio per -1% methylation > 1.03, P < 8.0 × 10-5 for four CpG sites; Validation III: 156 sporadic BC case and 151 controls, odds ratio per -1% methylation > 1.03, P < 6.0 × 10-4 for four CpG sites). In addition, the blood-based S100P methylation pattern was similar among BC patients with differential clinical characteristics regardless of stage, receptor status and menopause status. The observed BC-associated decreased S100P methylation in blood mainly originates from the leucocytes subpopulations but not B cells. The methylation levels of most S100P CpG sites were inversely correlated with the expression of S100P in leucocytes (P < 1.2 × 10-4) and in tissue (P < 1.1 × 10-4). This study reveals significant association between blood-based decreased S100P methylation and BC, and provides another proof for the application of altered DNA methylation signatures from blood cells as potential markers for the detection of BC, especially for the early stage. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  1. The effect of personal, familial, and environmental characteristics on acne vulgaris: a prospective, multicenter, case controlled study from Turkey.

    PubMed

    Karadağ, Ayşe S; Balta, İlknur; Saricaoğlu, Hayriye; Kiliç, Selim; Kelekçi, Kıymet H; Yildirim, Mehmet; Arica, Deniz A; Öztürk, Savaş; Karaman, Göksun; Çerman, Aslı A; Bilgili, Serap G; Turan, Enver; Demirci, Mustafa M; Uzunçakmak, Tuğba K; Güvenç, Serdar C; Ataseven, Arzu; Ferahbaş, Ayten; Aksoy, Berna; Çölgeçen, Emine; Ekiz, Özlem; Topaloğlu Demir, Filiz; Bilgiç, Özlem; Çakmak, Seray; Uçmak, Derya; Özuğuz, Pınar; Kaymak Konkuralp, Yeşim; Ermertcan, Aylin T; Gökdemir, Gonca; Bülbül Başkan, Emel; Alyamaç, Gökçen; Şanli, Hatice

    2017-07-11

    There are only a few studies about epidemiological features of acne vulgaris in the literature. The aim of this study was to analyze demographic, clinical, familial and environmental characteristics of acne, the role of diet and aggravating factors and association of these factors with acne severity. Patients with a diagnosis of mild-moderate to severe acne were consecutively interviewed at the participating centers during the study period. A total of 3826 patients and 759 control patients were involved in this study. Mild acne was the most common type of acne, and most of the lesions were localized on face followed by the trunk. The severity of acne was worse in patients who had a positive family history of acne. The most common triggering factor was psychological stress. We found a positive correlation with chocolate, bread, green tea, milk, white sugar, ripe banana, ice cream, apple, orange, and red meat consumption. As we compare the acne severity according to geographical features we detected mildmoderate acne was more common in Mediterrenean region and severe acne was more common in East Anatolian region. Family history positivity was more common in Aegean region and least common in Middle Anatolian region. There was statistically significant relationship as we compare acne severity and dietary factors such as chocolate, dairy products such as milk, sunflower seed consumption within the geographical regions. This study presents the demographic and clinical characteristics of acne patients in Asian and the European parts of Turkey. We believe that this study will provide a useful overview of acne in Turkey.

  2. Head trauma and Parkinson's disease: results from an Italian case-control study.

    PubMed

    Nicoletti, Alessandra; Vasta, Rosario; Mostile, Giovanni; Nicoletti, Giuseppe; Arabia, Gennarina; Iliceto, Giovanni; Lamberti, Paolo; Marconi, Roberto; Morgante, Letterio; Barone, Paolo; Quattrone, Aldo; Zappia, Mario

    2017-07-26

    We evaluated the possible association between head trauma and Parkinson's disease (PD). The FRAGAMP (Fattori di Rischio Ambientali e Genetici Associati alla Malattia di Parkinson) study is a large Italian multicenter case-control study carried out to evaluate the possible role of environmental and genetic factors in PD. Cases and controls were enrolled from six movement disorders centers located in the Central-Southern Italy. A standardized questionnaire was administered to record demographic, epidemiological, and clinical data. Positive history of head trauma was considered only if the head trauma preceded the onset of PD. All cases and controls underwent a standard neurological examination. Adjusted ORs and 95% CI were estimated using multivariate analysis (logistic regression). Four hundred ninety-two PD patients (292 men and 200 women) and 459 controls (160 men and 299 women) were enrolled in the study. A positive history for head trauma was reported by 106 (21.5%) PD patients and by 62 (13.5%) healthy controls. Multivariate analysis (OR adjusted by age, sex, family history, coffee smoking, and alcohol consumption) showed a significant positive association between PD and head trauma with an adjusted OR of 1.50 (95%CI 1.04-2.17; p value 0.03). In agreement with literature data, our study supports the positive association between head trauma and PD.

  3. Outdoor air pollution and cardiovascular diseases in Lebanon: a case-control study.

    PubMed

    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.

  4. Improving statistical analysis of matched case-control studies.

    PubMed

    Conway, Aaron; Rolley, John X; Fulbrook, Paul; Page, Karen; Thompson, David R

    2013-06-01

    Matched case-control research designs can be useful because matching can increase power due to reduced variability between subjects. However, inappropriate statistical analysis of matched data could result in a change in the strength of association between the dependent and independent variables or a change in the significance of the findings. We sought to ascertain whether matched case-control studies published in the nursing literature utilized appropriate statistical analyses. Of 41 articles identified that met the inclusion criteria, 31 (76%) used an inappropriate statistical test for comparing data derived from case subjects and their matched controls. In response to this finding, we developed an algorithm to support decision-making regarding statistical tests for matched case-control studies.

  5. Pooled exposure assessment for matched case-control studies.

    PubMed

    Saha-Chaudhuri, Paramita; Umbach, David M; Weinberg, Clarice R

    2011-09-01

    Exposure assessment using biologic specimens is important for epidemiology but may become impracticable if assays are expensive, specimen volumes are marginally adequate, or analyte levels fall below the limit of detection. Pooled exposure assessment can provide an effective remedy for these problems in unmatched case-control studies. We extend pooled exposure strategies to handle specimens collected in a matched case-control study. We show that if a logistic model applies to individuals, then a logistic model also applies to an analysis using pooled exposures. Consequently, the individual-level odds ratio can be estimated while conserving both cost and specimen. We discuss appropriate pooling strategies for a single exposure, with adjustment for multiple, possibly continuous, covariates (confounders) and assessment of effect modification by a categorical variable. We assess the performance of the approach via simulations and conclude that pooled strategies can markedly improve efficiency for matched as well as unmatched case-control studies.

  6. 25-hydroxyvitamin D and breast cancer, colorectal cancer, and colorectal adenomas: case-control versus nested case-control studies.

    PubMed

    Grant, William B

    2015-02-01

    Existing literature includes concerns regarding reliability of case-control studies of breast cancer incidence with respect to 25-hydroxyvitamin D (25(OH)D) concentrations. For breast cancer, only case-control studies consistently find inverse correlations between 25(OH)D and breast cancer. However, for colorectal cancer, nested case-control studies find significant inverse correlations with respect to 25(OH)D concentrations at baseline for mean follow-up times of 7 years. This is a review of results currently existing in literature. I provide evidence that 25(OH)D concentration values are only useful for short follow-up times for breast cancer since it develops rapidly. To support the robust nature of breast cancer case-control studies, I show that results from 11 studies from seven countries align in a robust power-law fit to the odds ratio versus mean 25(OH)D concentrations. Case-control studies of breast cancer incidence rates provide reliable results. Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  7. Nested case-control studies in cohorts with competing events.

    PubMed

    Wolkewitz, Martin; Cooper, Ben S; Palomar-Martinez, Mercedes; Olaechea-Astigarraga, Pedro; Alvarez-Lerma, Francisco; Schumacher, Martin

    2014-01-01

    In nested case-control studies, incidence density sampling is the time-dependent matching procedure to approximate hazard ratios. The cumulative incidence function can also be estimated if information from the full cohort is used. In the presence of competing events, however, the cumulative incidence function depends on the hazard of the disease of interest and on the competing events hazard. Using hospital-acquired infection as an example (full cohort), we propose a sampling method for nested case-control studies to estimate subdistribution hazard ratios. With further information on the full cohort, the cumulative incidence function for the event of interest can then be estimated as well.

  8. Impact of preoperative immunonutrition on morbidity following cystectomy for bladder cancer: a case-control pilot study.

    PubMed

    Bertrand, J; Siegler, N; Murez, T; Poinas, G; Segui, B; Ayuso, D; Gres, P; Wagner, L; Thuret, R; Costa, P; Droupy, S

    2014-02-01

    To compare postoperative complications in patients with or without preoperative immunonutrition before cystectomy. A prospective, multicenter, pilot, case-control study was conducted during 6 months. Patients with 7-day preoperative immunonutrition were prospectively included and compared with a retrospective, matched control group without immunonutrition. Early complication rates and the length of hospital stay were analyzed. The bilateral type I error was <0.05; the power was 90%. Thirty patients in each group were required. Thirty patients were included in each group, on a comparable basis. In the immunonutrition group, fewer postoperative complications (40 vs. 76.7%; p = 0.008), less paralytic ileus at D7 (6.6 vs. 33.3%; p = 0.02), fewer infections (23.3 vs. 60%; p = 0.008), and in particular less pyelonephritis (16.7 vs. 46.7%; p = 0.03) occurred. Clavien's grades for complications were higher in the control group (p = 0.04). Mortality, pulmonary embolism, anastomotic fistulae, and wound dehiscence were similar between two groups. The length of stay was reduced by 3 days in the immunonutrition group. In this pilot case-control study, immunonutrition is associated with a decrease in postoperative complications, urinary tract infections, Clavien's grade for complications, and paralytic ileus in patients undergoing cystectomy for bladder cancer. Prospective randomized placebo control studies are needed to confirm these promising results.

  9. [Case-control studies in psychiatry: causality, design and warnings].

    PubMed

    Silva Ayçaguer, L C

    2004-01-01

    This present paper is mainly methodological and has been written with the aim of helping researchers in psychiatry to produce results with higher quality and help readers to have adequate assessment values of others. Brief reflection is made on the most important conditions that must be fulfilled to prove a causality hypothesis, regardless of the investigation design used. However, the main purpose of the text is to examine and illustrate how these conditions work under a case-control study environment. Besides outlining the basic aspects concerning design and analysis, areas extremely illustrated with examples of case and controls in psychiatry found in the literature, a number of suggestions to avoid pitfalls that can invalidate research efforts developed using case-control methodology is offered.

  10. A case-control study of amyotrophic lateral sclerosis.

    PubMed

    Savettieri, G; Salemi, G; Arcara, A; Cassata, M; Castiglione, M G; Fierro, B

    1991-01-01

    A retrospective case-control study was conducted using 46 patients affected by amyotrophic lateral sclerosis and 92 closely matched healthy controls. Cases were ascertained through typical clinical and instrumental findings. Putative risk factors (bone fractures or major trauma, exposure to domestic animals, surgical operations, disease among first degree relatives and others) were investigated anamnestically using a standard questionnaire. Using Mantel-Haenzsel estimates of the odds ratio, no association was found between amyotrophic lateral sclerosis and the investigated variables.

  11. Non-Hodgkin's lymphoma: case control epidemiological study in Yorkshire.

    PubMed

    Cartwright, R A; McKinney, P A; O'Brien, C; Richards, I D; Roberts, B; Lauder, I; Darwin, C M; Bernard, S M; Bird, C C

    1988-01-01

    This paper reports the results of a case control study of non-Hodgkin's lymphoma in the Yorkshire Health Region. In all, 437 cases and 724 controls were interviewed. Risk factors associated with past skin conditions, family history of cancer and infectious mononucleosis, aspects of social life and contact with wood dust and epoxy glues all emerge. A comparison of high and low grade morphological forms of disease reveal contrasting risks and suggest separate aetiologies for these conditions.

  12. Survey research methods in evaluation and case-control studies.

    PubMed

    Kalton, Graham; Piesse, Andrea

    2007-04-15

    Survey research methods are widely used in two types of analytic studies: evaluation studies that measure the effects of interventions; and population-based case-control studies that investigate the effects of various risk factors on the presence of disease. This paper provides a broad overview of some design and analysis issues related to such studies, illustrated with examples. The lack of random assignment to treatment and control groups in many evaluation studies makes controlling for confounders critically important. Confounder control can be achieved by matching in the design and by various alternative methods in the analysis. One popular analytic method of controlling for confounders is propensity scoring, which bears a close resemblance to survey weighting. The use of population-based controls has become common in case-control studies. For reasons of cost, population-based controls are often identified by telephone surveys using random digit dialling (RDD) sampling methods. However, RDD surveys are now experiencing serious problems with response rates. A recent alternative approach is to select controls from frames such as driver license lists that contain valuable demographic information for use in matching. Methods of analysis developed in the survey sampling literature are applicable, at least to some degree, in the analyses of evaluation and population-based case-control studies. In particular, the effects of complex sample designs can be taken into account using survey sampling variance estimation methods. Several survey analysis software packages are available for carrying out the computations.

  13. Methodology Series Module 2: Case-control Studies.

    PubMed

    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.

  14. Nested case-control studies: should one break the matching?

    PubMed

    Borgan, Ørnulf; Keogh, Ruth

    2015-10-01

    In a nested case-control study, controls are selected for each case from the individuals who are at risk at the time at which the case occurs. We say that the controls are matched on study time. To adjust for possible confounding, it is common to match on other variables as well. The standard analysis of nested case-control data is based on a partial likelihood which compares the covariates of each case to those of its matched controls. It has been suggested that one may break the matching of nested case-control data and analyse them as case-cohort data using an inverse probability weighted (IPW) pseudo likelihood. Further, when some covariates are available for all individuals in the cohort, multiple imputation (MI) makes it possible to use all available data in the cohort. In the paper we review the standard method and the IPW and MI approaches, and compare their performance using simulations that cover a range of scenarios, including one and two endpoints.

  15. Assessment of global phase uncertainty in case-control studies

    PubMed Central

    Uh, Hae-Won; Houwing-Duistermaat, Jeanine J; Putter, Hein; van Houwelingen, Hans C

    2009-01-01

    Background In haplotype-based candidate gene studies a problem is that the genotype data are unphased, which results in haplotype ambiguity. The measure [1] quantifies haplotype predictability from genotype data. It is computed for each individual haplotype, and for a measure of global relative efficiency a minimum value is suggested. Alternatively, we developed methods directly based on the information content of haplotype frequency estimates to obtain global relative efficiency measures: and based on A- and D-optimality, respectively. All three methods are designed for single populations; they can be applied in cases only, controls only or the whole data. Therefore they are not necessarily optimal for haplotype testing in case-control studies. Results A new global relative efficiency measure was derived to maximize power of a simple test statistic that compares haplotype frequencies in cases and controls. Application to real data showed that our proposed method gave a clear and summarizing measure for the case-control study conducted. Additionally this measure might be used for selection of individuals, who have the highest potential for improving power by resolving phase ambiguity. Conclusion Instead of using relative efficiency measure for cases only, controls only or their combined data, we link uncertainty measure to case-control studies directly. Hence, our global efficiency measure might be useful to assess whether data are informative or have enough power for estimation of a specific haplotype risk. PMID:19751505

  16. Assessment of global phase uncertainty in case-control studies.

    PubMed

    Uh, Hae-Won; Houwing-Duistermaat, Jeanine J; Putter, Hein; van Houwelingen, Hans C

    2009-09-14

    In haplotype-based candidate gene studies a problem is that the genotype data are unphased, which results in haplotype ambiguity. The R(h)(2) measure 1 quantifies haplotype predictability from genotype data. It is computed for each individual haplotype, and for a measure of global relative efficiency a minimum R(h)(2) value is suggested. Alternatively, we developed methods directly based on the information content of haplotype frequency estimates to obtain global relative efficiency measures: R(A)(2) and R(D)(2) based on A- and D-optimality, respectively. All three methods are designed for single populations; they can be applied in cases only, controls only or the whole data. Therefore they are not necessarily optimal for haplotype testing in case-control studies. A new global relative efficiency measure R(T)(2) was derived to maximize power of a simple test statistic that compares haplotype frequencies in cases and controls. Application to real data showed that our proposed method R(T)(2) gave a clear and summarizing measure for the case-control study conducted. Additionally this measure might be used for selection of individuals, who have the highest potential for improving power by resolving phase ambiguity. Instead of using relative efficiency measure for cases only, controls only or their combined data, we link uncertainty measure to case-control studies directly. Hence, our global efficiency measure might be useful to assess whether data are informative or have enough power for estimation of a specific haplotype risk.

  17. Mobile phone use and brain tumours in the CERENAT case-control study.

    PubMed

    Coureau, Gaëlle; Bouvier, Ghislaine; Lebailly, Pierre; Fabbro-Peray, Pascale; Gruber, Anne; Leffondre, Karen; Guillamo, Jean-Sebastien; Loiseau, Hugues; Mathoulin-Pélissier, Simone; Salamon, Roger; Baldi, Isabelle

    2014-07-01

    The carcinogenic effect of radiofrequency electromagnetic fields in humans remains controversial. However, it has been suggested that they could be involved in the aetiology of some types of brain tumours. The objective was to analyse the association between mobile phone exposure and primary central nervous system tumours (gliomas and meningiomas) in adults. CERENAT is a multicenter case-control study carried out in four areas in France in 2004-2006. Data about mobile phone use were collected through a detailed questionnaire delivered in a face-to-face manner. Conditional logistic regression for matched sets was used to estimate adjusted ORs and 95% CIs. A total of 253 gliomas, 194 meningiomas and 892 matched controls selected from the local electoral rolls were analysed. No association with brain tumours was observed when comparing regular mobile phone users with non-users (OR=1.24; 95% CI 0.86 to 1.77 for gliomas, OR=0.90; 95% CI 0.61 to 1.34 for meningiomas). However, the positive association was statistically significant in the heaviest users when considering life-long cumulative duration (≥896 h, OR=2.89; 95% CI 1.41 to 5.93 for gliomas; OR=2.57; 95% CI 1.02 to 6.44 for meningiomas) and number of calls for gliomas (≥18,360 calls, OR=2.10, 95% CI 1.03 to 4.31). Risks were higher for gliomas, temporal tumours, occupational and urban mobile phone use. These additional data support previous findings concerning a possible association between heavy mobile phone use and brain tumours. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  18. A case-control study of dietary salt intake in pediatric-onset multiple sclerosis.

    PubMed

    McDonald, Jamie; Graves, Jennifer; Waldman, Amy; Lotze, Timothy; Schreiner, Teri; Belman, Anita; Greenberg, Benjamin; Weinstock-Guttman, Bianca; Aaen, Gregory; Tillema, Jan-Mendelt; Hart, Janace; Lulu, Sabeen; Ness, Jayne; Harris, Yolanda; Rubin, Jennifer; Candee, Meghan; Krupp, Lauren B; Gorman, Mark; Benson, Leslie; Rodriguez, Moses; Chitnis, Tanuja; Mar, Soe; Barcellos, Lisa F; Laraia, Barbara; Rose, John; Roalstad, Shelly; Simmons, Timothy; Casper, T Charles; Waubant, Emmanuelle

    2016-03-01

    High salt intake may be associated with pro-inflammatory changes in the immune response, and increased clinical and MRI activity in adults with relapsing-remitting multiple sclerosis. We sought to determine if dietary salt intake is associated with pediatric-onset MS risk in a multicenter, case-control study. Pediatric-onset CIS/MS cases within four years of onset and controls less than 22 years old recruited from 14 pediatric-MS centers were studied. Dietary sodium intake was assessed using the validated Block Kids Food Screener (NutritionQuest). Sodium intake, excess sodium, and sodium terciles were compared between cases and controls. Logistic regression models were adjusted for age, gender, ethnicity, body mass index, and socioeconomic status. Among 170 cases (mean age=15.2±3.5) and 331 controls (mean age=14.0±3.7), no significant difference in unadjusted mean sodium intake was found between cases (2044mg/d) and controls (2030mg/d, p=0.99). The proportion of subjects consuming excess sodium, based on the adequate intake for age and gender, was similar between cases and controls (65% versus 69%, p=0.34). There were no increased odds of higher sodium intake among cases as compared to controls (for each 100mg/d increase in sodium, OR=1.00, 95% CI 0.98, 1.02; p=0.93, for excess sodium intake, OR=1.05, 95% CI 0.67, 1.64; p=0.84). Our results show no strong association between dietary salt intake and pediatric-onset MS risk, suggesting that salt intake may not play a prominent role in susceptibility to MS in children. Copyright © 2016. Published by Elsevier B.V.

  19. Dietary water intake and bladder cancer risk: An Italian case-control study.

    PubMed

    Di Maso, Matteo; Bosetti, Cristina; Taborelli, Martina; Montella, Maurizio; Libra, Massimo; Zucchetto, Antonella; Turati, Federica; Parpinel, Maria; Negri, Eva; Tavani, Alessandra; Serraino, Diego; Ferraroni, Monica; La Vecchia, Carlo; Polesel, Jerry

    2016-12-01

    Previous studies on the relationship between fluid intake and risk of bladder cancer have generally focused on beverages, and results have been inconsistent. We investigated the relationship between water intake and bladder cancer risk, considering water from both beverages and foods. Between 2003 and 2014 we conducted a multicenter hospital-based case-control study in Italy on 690 cases and 665 frequency-matched controls. Water intake for beverages and foods was computed using the Italian food composition database. Odds ratios (ORs) and the corresponding 95% confidence intervals (95%CIs) for water intake were estimated by unconditional multiple logistic regression models, adjusting for major risk factors for bladder cancer. In the control group, the 64.7% of water intake derived from beverages and 35.4% from foods. Comparing the highest with the lowest quartile of intake, water from beverages (OR=1.14; 95%CI: 0.82-1.59) and water from foods (OR=0.88; 95%CI: 0.61-1.28) were not significantly associated with bladder cancer risk. Some specific water sources showed significant associations with bladder cancer risk (e.g. water from vegetables, OR=0.58; 95%CI: 0.40-0.86). However, these associations may be due to the effect of other components contained in beverages and foods rather than to the water content itself. Considering the intakes of water from both beverages and foods, total water intake was not associated with bladder cancer risk. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Dietary inflammatory index and non-Hodgkin lymphoma risk in an Italian case-control study.

    PubMed

    Shivappa, Nitin; Hébert, James R; Taborelli, Martina; Montella, Maurizio; Libra, Massimo; Zucchetto, Antonella; Crispo, Anna; Grimaldi, Maria; La Vecchia, Carlo; Serraino, Diego; Polesel, Jerry

    2017-07-01

    While dietary factors have been shown to play an important etiologic role in non-Hodgkin lymphoma (NHL), little is known about the association between inflammatory properties of diet and NHL risk. We explored the association between the dietary inflammatory index (DII) and NHL risk in a multicenter Italian case-control study conducted between 1999 and 2014. Cases were 536 subjects with incident, histologically confirmed NHL from three areas in Italy. Controls were 984 subjects admitted to the same network of hospitals as the cases for acute, nonmalignant conditions, unrelated to diet. DII scores were computed based on 30 nutrients and food items assessed using a reproducible and validated 78-item food-frequency questionnaire. Odds ratios (ORs) were estimated through logistic regression models adjusting for age, total energy intake, and other recognized confounding factors. Subjects in the highest quartile of DII scores (i.e., with the most pro-inflammatory diets) had a higher risk of NHL compared with subjects in the lowest quartile (i.e., with the most anti-inflammatory diets) (ORQuartile4vs1 1.61, 95% confidence interval CI 1.07-2.43; p-trend = 0.01). Stratified analyses produced stronger associations between DII and NHL among males (ORQuartile4vs1 2.14; 95% CI 1.25-3.67) with significant heterogeneity (p value = 0.02); when analyzed by histologic subtype, a significant association was observed with diffuse large B-cell lymphoma (ORQuartile4vs1 1.84; 95% CI 1.09-3.10). A pro-inflammatory diet, as indicated by higher DII scores, is associated with elevated odds of NHL, especially among males.

  1. A case-control study of dietary salt intake in pediatric-onset multiple sclerosis

    PubMed Central

    McDonald, Jamie; Graves, Jennifer; Waldman, Amy; Lotze, Timothy; Schreiner, Teri; Belman, Anita; Greenberg, Benjamin; Weinstock-Guttman, Bianca; Aaen, Gregory; Tillema, Jan-Mendelt; Hart, Janace; Lulu, Sabeen; Ness, Jayne; Harris, Yolanda; Rubin, Jennifer; Candee, Meghan; Krupp, Lauren B.; Gorman, Mark; Benson, Leslie; Rodriguez, Moses; Chitnis, Tanuja; Mar, Soe; Barcellos, Lisa F.; Laraia, Barbara; Rose, John; Roalstad, Shelly; Simmons, Timothy; Casper, T. Charles; Waubant, Emmanuelle

    2016-01-01

    Background High salt intake may be associated with pro-inflammatory changes in the immune response, and increased clinical and MRI activity in adults with relapsing-remitting multiple sclerosis. Objective We sought to determine if dietary salt intake is associated with pediatric-onset MS risk in a multicenter, case-control study. Methods Pediatric-onset CIS/MS cases within four years of onset and controls less than 22 years old recruited from 14 pediatric-MS centers were studied. Dietary sodium intake was assessed using the validated Block Kids Food Screener (NutritionQuest). Sodium intake, excess sodium, and sodium terciles were compared between cases and controls. Logistic regression models were adjusted for age, gender, ethnicity, body mass index, and socioeconomic status. Results Among 170 cases (mean age=15.2±3.5) and 331 controls (mean age=14.0±3.7), no significant difference in unadjusted mean sodium intake was found between cases (2044 mg/d) and controls (2030 mg/d, p=0.99). The proportion of subjects consuming excess sodium, based on the adequate intake for age and gender, was similar between cases and controls (65% versus 69%, p=0.34). There were no increased odds of higher sodium intake among cases as compared to controls (for each 100 mg/d increase in sodium, OR=1.00, 95% CI 0.98, 1.02; p=0.93, for excess sodium intake, OR=1.05, 95% CI 0.67, 1.64; p=0.84). Conclusions Our results show no strong association between dietary salt intake and pediatric-onset MS risk, suggesting that salt intake may not play a prominent role in susceptibility to MS in children. PMID:27063630

  2. Euclidean supergravity and multi-centered solutions

    NASA Astrophysics Data System (ADS)

    Sabra, W. A.

    2017-04-01

    In ungauged supergravity theories, the no-force condition for BPS states implies the existence of stable static multi-centered solutions. The first solutions to Einstein-Maxwell theory with a positive cosmological constant describing an arbitrary number of charged black holes were found by Kastor and Traschen. Generalisations to five and higher dimensional theories were obtained by London. Multi-centered solutions in gauged supergravity, even with time-dependence allowed, have yet to be constructed. In this letter we construct supersymmetry-preserving multi-centered solutions for the case of D = 5, N = 2 Euclidean gauged supergravity coupled to an arbitrary number of vector multiplets. Higher dimensional Einstein-Maxwell multi-centered solutions are also presented.

  3. Risk factors associated with lipomyelomeningocele: a case-control study.

    PubMed

    Esmaeili, Arash; Hanaei, Sara; Fadakar, Kaveh; Dadkhah, Sahar; Arjipour, Mahdi; Habibi, Zohreh; Nejat, Farideh; El Khashab, Mostafa

    2013-01-01

    In general, it seems that both genetic and environmental factors play important roles in the induction of neural tube defects. Lipomyelomeningocele (LipoMMC) is a rather common type of closed neural tube defect, but only limited studies have investigated the potential risk factors of this anomaly. Therefore, the purpose of this case-control study was to investigate the risk factors involved in LipoMMC formation. Various risk factors were evaluated in 35 children between 1 month and 10 years of age with LipoMMC in a hospital-based case-control study. The 2 control arms consisted of 35 children with myelomeningocele (MMC group) and 35 children with congenital anomalies other than central nervous system problems (control group). All groups were matched for age and visited the same hospital. A structured questionnaire was used for the collection of all data, including the mothers' weight and height during pregnancy, education, reproductive history, previous abortions, and socioeconomic status, as well as the parents' consanguinity and family history of the same anomalies. Univariate analysis of the children with LipoMMC compared to the control group showed that the use of periconceptional folic acid supplementation was significantly lower in the MMC and LipoMMC groups compared to the control group. In addition, comparison of the MMC and control groups revealed statistically significant differences regarding the use of folic acid and maternal obesity. In multivariate analysis, use of folic acid in the periconceptional period and during the first trimester was an independent risk factor for LipoMMC and MMC. Furthermore, maternal obesity was a significantly positive risk factor for MMC. The probable risk factors for LipoMMC were investigated in this case-control study. Consumption of folic acid in the periconceptional period and during the first trimester is an independent protective factor against LipoMMC. It seems that larger studies are needed to examine other possible

  4. 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

  5. The Global Enteric Multicenter Study (GEMS): impetus, rationale, and genesis.

    PubMed

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

    2012-12-01

    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.

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

    PubMed Central

    Booth, M.; Beral, V.; Smith, P.

    1989-01-01

    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. PMID:2679848

  7. Chronic lymphocytic leukaemia: case control epidemiological study in Yorkshire.

    PubMed Central

    Cartwright, R. A.; Bernard, S. M.; Bird, C. C.; Darwin, C. M.; O'Brien, C.; Richards, I. D.; Roberts, B.; McKinney, P. A.

    1987-01-01

    This is the second report of a large case control study of lymphoma/leukaemia occurring in Yorkshire during 1979-84, and deals with chronic lymphocytic leukaemia presenting either in its haematological (CLL) or more solid lymphomatous (malignant lymphoma-lymphocytic or MLL) forms. In all, 330 cases and 561 controls were interviewed. The results support the concept that CLL/MLL is a condition of multiple aetiologies with evidence for genetic predisposition through an excess of family cases, immune perturbation demonstrated by excessive previous skin diseases and phenylbutazone use, and viral involvement shown by links with infectious diseases and multiple sclerosis. PMID:3304389

  8. Chronic lymphocytic leukaemia: case control epidemiological study in Yorkshire.

    PubMed

    Cartwright, R A; Bernard, S M; Bird, C C; Darwin, C M; O'Brien, C; Richards, I D; Roberts, B; McKinney, P A

    1987-07-01

    This is the second report of a large case control study of lymphoma/leukaemia occurring in Yorkshire during 1979-84, and deals with chronic lymphocytic leukaemia presenting either in its haematological (CLL) or more solid lymphomatous (malignant lymphoma-lymphocytic or MLL) forms. In all, 330 cases and 561 controls were interviewed. The results support the concept that CLL/MLL is a condition of multiple aetiologies with evidence for genetic predisposition through an excess of family cases, immune perturbation demonstrated by excessive previous skin diseases and phenylbutazone use, and viral involvement shown by links with infectious diseases and multiple sclerosis.

  9. Multicenter Breast Cancer Collaborative Registry

    PubMed Central

    Sherman, Simon; Shats, Oleg; Fleissner, Elizabeth; Bascom, George; Yiee, Kevin; Copur, Mehmet; Crow, Kate; Rooney, James; Mateen, Zubeena; Ketcham, Marsha A.; Feng, Jianmin; Sherman, Alexander; Gleason, Michael; Kinarsky, Leo; Silva-Lopez, Edibaldo; Edney, James; Reed, Elizabeth; Berger, Ann; Cowan, Kenneth

    2011-01-01

    The Breast Cancer Collaborative Registry (BCCR) is a multicenter web-based system that efficiently collects and manages a variety of data on breast cancer (BC) patients and BC survivors. This registry is designed as a multi-tier web application that utilizes Java Servlet/JSP technology and has an Oracle 11g database as a back-end. The BCCR questionnaire has accommodated standards accepted in breast cancer research and healthcare. By harmonizing the controlled vocabulary with the NCI Thesaurus (NCIt) or Systematized Nomenclature of Medicine-Clinical Terms (SNOMED-CT), the BCCR provides a standardized approach to data collection and reporting. The BCCR has been recently certified by the National Cancer Institute’s Center for Biomedical Informatics and Information Technology (NCI CBIIT) as a cancer Biomedical Informatics Grid (caBIG®) Bronze Compatible product. The BCCR is aimed at facilitating rapid and uniform collection of critical information and biological samples to be used in developing diagnostic, prevention, treatment, and survivorship strategies against breast cancer. Currently, seven cancer institutions are participating in the BCCR that contains data on almost 900 subjects (BC patients and survivors, as well as individuals at high risk of getting BC). PMID:21918596

  10. Association between migraine and asthma: matched case-control study.

    PubMed Central

    Davey, Gail; Sedgwick, Philip; Maier, Will; Visick, George; Strachan, David P; Anderson, H Ross

    2002-01-01

    BACKGROUND: Earlier studies have suggested a link between asthma and severe headache, and also between migraine and wheezing illness. Recent analysis have also shown an increase of asthma among cases with a prior history of migraine but without a history of hay fever, allergic rhinitis or eczema. AIM: To examine whether there is an association between migraine and asthma in the United Kingdom. DESIGN OF STUDY: Matched case-control study using the General Practice Research Database (GPRD). SETTING: Practices in the United Kingdom providing data on 5,110,619 patients to the GPRD. METHOD: The subjects were the patients with one or more diagnoses of migraine plus treatment for migraine. Each case was matched by general practice, sex, and age, with one control who had never been given a diagnosis of migraine. Case and control groups were compared for prevalence of asthma, chronic obstructive pulmonary disease, respiratory symptoms treated with inhalers or hay fever. Investigations were carried out to determine whether the association between migraine and asthma was stronger among patients with hayfever or those without hayfever, and whether patients with migraine had an increased prescription of other (non-migraine and non-asthma) medications. RESULTS: Among 64 678 case-control pairs, the relative risk of asthma in patients with migraine was 1.59 (95% CI = 1.54 to 1.65) among definite cases, and 0.75 (95% CI = 0.67 to 0.83) among those whose selection as case included beta-blocker prophylaxis. Among definite migraine cases, relative risks of chronic obstructive pulmonary disease, respiratory symptoms, eczema, and hay fever (pollinosis), were all raised (at 1.22, 1.85, 1.55, and 1.67, respectively). The association between migraine and asthma was stronger in patients without a diagnosis of hay fever, than in those with hayfever (relative risk = 1.32 and 1.19, respectively). The relative risk of prescription for a range of non-migraine, non-asthma medications was raised

  11. Case Control Polysomnographic Studies of Sleep Disorders in Parkinson's Disease

    PubMed Central

    Yong, Ming-Hui; Fook-Chong, Stephanie; Pavanni, Ratnagopal; Lim, Li-Ling; Tan, Eng-King

    2011-01-01

    Background The relationship between a number of primary sleep disorders and Parkinson's disease (PD) is still debated. There are limited case control polysomnographic studies in PD and most of these study sample sizes are small. Methodology/Findings We conducted one of the largest case-control studies involving overnight polysomnographic evaluation, with prospective recruitment of unselected Parkinson's disease patients and healthy controls from an Asian population. The cases were recruited from the specialized movement disorder outpatient clinics in a tertiary referral center, and controls from the same geographical locations. All subjects underwent an overnight polysomnographic study and a multiple sleep latency test. A total of 124 subjects including 56 patients and 68 controls frequency-matched for age and sex were included. Multivariate analysis revealed that patients had significantly shorter total sleep time than controls (p = 0.01), lower sleep efficiency (p = 0.001) and increased REM latency (p = 0.007). In patients, multivariate analysis showed that reduced total sleep time was significantly associated with increased age (p = 0.001) and increased levodopa dose (p = 0.032). The mean Insomnia Severity Index was higher in PD patients (9.0±7.1) compared to controls (3.3±3.9, p<0.001). The mean Epworth Sleepiness Scale score was higher in PD patients (9.3±5.9 vs. 5.7±4.8, p<0.001). Nocturnal arousals, obstructive sleep apnea, periodic leg movements and objective abnormal sleepiness were not increased in our patients. Conclusions/Significance Our case-control polysomnographic study, the first-ever performed in an Asian population, revealed altered sleep architecture and reduced sleep in PD patients compared to controls. Reduced total sleep time was associated with increased age and levodopa dose. However, nocturnal arousals, primary sleep disorders and abnormal sleepiness were not increased in our PD patients suggesting that ethnic

  12. Nigerian juvenile offenders: a case-controlled study.

    PubMed

    Ogunlesi, A O

    1991-01-01

    A case-controlled study was carried out on all the 51 juvenile delinquents found in a point prevalence survey of a Nigerian Borstal Remand Centre. Mean age of the delinquents was 17-27 years. They were mostly from the low social class (70.6%) and the commonest reason for admission was for being beyond parental control (68.6%). Identified risk factors found for juvenile delinquency were death of biological mother, parental marital failure, growing up with relatives rather than parents, drug abuse and ordinal position in the family. Possible cultural explanations for some of these observations were proffered. The need to improve on the living conditions of these juveniles and their assessment procedure were highlighted. Finally, it is imperative that the obsolete Nigerian Children and Young Person's Law be updated.

  13. 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.

  14. Childhood cancer and overhead powerlines: a case-control study.

    PubMed Central

    Myers, A.; Clayden, A. D.; Cartwright, R. A.; Cartwright, S. C.

    1990-01-01

    A case-control study has been carried out to examine the occurrence of childhood cancer in relation to the proximity of overhead power lines to a child's home address at birth and to the calculated magnetic field at the address. The study included 374 cases diagnosed in the Yorkshire Health Region between 1970 and 1979, together with 588 matched controls. Magnetic-field strengths at the birth addresses due to the load currents of overhead power lines were calculated on the basis of line-network maps and load records. The results indicate no association between the occurrence of childhood malignancies and either the proximity or the magnetic fields of overhead lines, although the statistical power of the study was limited by the small numbers of children living close to overhead power lines. PMID:2257204

  15. Case-control study of respiratory cancer and employment

    SciTech Connect

    Glazer, E.R.; Chiang, M.L.

    1984-04-01

    A multiple logistic risk-analysis procedure was used to compare data from 346 case/control pairs to determine occupational/industrial risk factors for respiratory cancer. The duration of employment was considered in blue-collar production occupations. Five industrial categories were included: shipyard, petrochemical, metal-related, construction and a grouping of other occupations under a single heading. The bulk of this grouped category was made up of blue collar employees in the industries of transportation, food production, wholesale and retail trade, professional services, and public administration. Specific attention was given to asbestos exposure, cigarette smoking, educational level attained, and dietary factors such as consumption of vegetables, fruits, and alcohol. A moderately elevated risk for respiratory cancer existed among employees in the metal industry and grouped categories when employment was over 30 years duration. In the metal industry this increase was almost entirely due to a larger than expected number of cases of larynx cancer.

  16. Risk factors for anal fistula: a case-control study.

    PubMed

    Wang, D; Yang, G; Qiu, J; Song, Y; Wang, L; Gao, J; Wang, C

    2014-07-01

    The aim of our study was to identify potential risk factors for anal fistula in order to improve prevention and treatment of anal fistula. A retrospective case-control study for anal fistula was conducted at our unit. Logistic regression analyses were carried out to identify associated risk factors for anal fistula. The final model obtained by the stepwise forward logistic regression analysis method identified the following items as independent risk factors: body mass index of >25.0 kg/m(2), high daily salt intake, history of diabetes, hyperlipidemia, dermatosis, anorectal surgery, history of smoking and alcohol intake, sedentary lifestyle, excessive intake of spicy/greasy food, very infrequent participation in sports and prolonged sitting on the toilet for defecation. Our results indicate that lifestyle factors and certain medical conditions increase an individual's risk of developing anal fistula.

  17. A case-control study of Alzheimer's disease in Australia.

    PubMed

    Broe, G A; Henderson, A S; Creasey, H; McCusker, E; Korten, A E; Jorm, A F; Longley, W; Anthony, J C

    1990-11-01

    We conducted a case-control study of clinically diagnosed Alzheimer's disease (AD) on 170 cases aged 52 to 96 years, and 170 controls matched for age, sex and, where possible, the general practice of origin. Trained lay interviewers naive to the hypotheses and to the clinical status of the elderly person carried out risk-factor interviews with informants. Significant odds ratios were found for 4 variables: a history of either dementia, probable AD, or Down's syndrome in a 1st-degree relative, and underactivity as a behavioral trait in both the recent and more distant past. Previously reported or suggested associations not confirmed by this study include head injury, starvation, thyroid disease, analgesic abuse, antacid use (aluminum exposure), alcohol abuse, smoking, and being left-handed.

  18. Metabolic Derangements in Lichen Planus - A Case Control Study

    PubMed Central

    Kar, Bikash Ranjan; Panda, Maitreyee

    2016-01-01

    Introduction An association between psoriasis and metabolic syndrome has been established in previous studies. Lichen Planus (LP) is also a chronic inflammatory disease morphologically related to psoriasis and few studies have shown association of metabolic derangements in LP. Aim To study the association of metabolic derangements in LP. Materials and Methods A prospective case control study was undertaken for a period of one year. Age and sex matched patients of LP and other non-inflammatory diseases were taken as cases and controls respectively. Data on height, weight, lipid profile and fasting blood glucose levels were collected for all the patients. Body Mass Index (BMI) was calculated. Results A total of 80 patients were recruited, 40 cases and 40 controls. The mean values for all the lipid and glucose parameters were high in cases as compared to controls with significant p-values. Conclusion In the present study metabolic derangements were seen in patients with LP. PMID:28050485

  19. PGA: power calculator for case-control genetic association analyses

    PubMed Central

    Menashe, Idan; Rosenberg, Philip S; Chen, Bingshu E

    2008-01-01

    Background Statistical power calculations inform the design and interpretation of genetic association studies, but few programs are tailored to case-control studies of single nucleotide polymorphisms (SNPs) in unrelated subjects. Results We have developed the "Power for Genetic Association analyses" (PGA) package which comprises algorithms and graphical user interfaces for sample size and minimum detectable risk calculations using SNP or haplotype effects under different genetic models and study constrains. The software accounts for linkage disequilibrium and statistical multiple comparisons. The results are presented in graphs or tables and can be printed or exported in standard file formats. Conclusion PGA is user friendly software that can facilitate decision making for association studies of candidate genes, fine-mapping studies, and whole-genome scans. Stand-alone executable files and a Matlab toolbox are available for download at: PMID:18477402

  20. Hodgkin's disease: case control epidemiological study in Yorkshire.

    PubMed Central

    Bernard, S. M.; Cartwright, R. A.; Darwin, C. M.; Richards, I. D.; Roberts, B.; O'Brien, C.; Bird, C. C.

    1987-01-01

    This is the first report of a case-control epidemiological study on lymphomas and leukaemias occurring in Yorkshire during 1979-84. This paper deals with the results of the Hodgkin's disease analysis comprising 248 cases and 489 controls. The results indicate support for previous work with respect to small family size and past history of infectious mononucleosis. Positive observations made in a previous pilot study are also confirmed and extended with respect to associations with certain chronic skin lesions, dental anaesthesia and familial factors. Negative associations are described with respect to X-ray exposures and cigarette smoking. It is proposed that these results fit into a general hypothesis that these conditions are the result of interaction between infectious agents and altered immunity in those persons genetically predisposed. PMID:3814482

  1. Hodgkin's disease: case control epidemiological study in Yorkshire.

    PubMed

    Bernard, S M; Cartwright, R A; Darwin, C M; Richards, I D; Roberts, B; O'Brien, C; Bird, C C

    1987-01-01

    This is the first report of a case-control epidemiological study on lymphomas and leukaemias occurring in Yorkshire during 1979-84. This paper deals with the results of the Hodgkin's disease analysis comprising 248 cases and 489 controls. The results indicate support for previous work with respect to small family size and past history of infectious mononucleosis. Positive observations made in a previous pilot study are also confirmed and extended with respect to associations with certain chronic skin lesions, dental anaesthesia and familial factors. Negative associations are described with respect to X-ray exposures and cigarette smoking. It is proposed that these results fit into a general hypothesis that these conditions are the result of interaction between infectious agents and altered immunity in those persons genetically predisposed.

  2. Toxocariasis and childhood asthma: A case-control study.

    PubMed

    Cadore, Priscila Silva; Zhang, Linjie; Lemos, Liliam de Lima; Lorenzi, Carolina; Telmo, Paula de Lima; Dos Santos, Paula Costa; Mattos, Gabriela Torres; Vignol, Flávia Saraçol; Prietsch, Silvio O M; Berne, Maria Elisabeth Aires; Scaini, Carlos James

    2016-08-01

    The objective of this study is to investigate the association between anti-Toxocara IgG seropositivity and asthma in children. This was a case-control study conducted in a university hospital in south Brazil between May 2012 and June 2013. Were recruited 208 children up to 12 years old of whom 156 had asthma (cases) and 52 did not have asthma (controls), with a case-control ratio of 3:1 matched by age. Children's parents or guardians were interviewed using a structured questionnaire with closed questions. Serology was performed using enzyme-linked immunosorbent assay (ELISA) with excretory-secretory antigen of Toxocara canis (TES). The seroprevalence of IgG anti-T. canis antibodies was 12.8% in the cases and 7.7% in the controls. There was no significant association between seropositivity to T. canis and risk of asthma (adjusted odds ratio [OR]: 1.89, 95% CI: 0.52 to 6.89, p = 0.33). Household income < 2 minimum salaries, paternal school years < 9, allergic rhinitis in children, a positive family history of asthma and rhinitis and contact with cats were significantly associated with asthma, with adjusted ORs (95% CIs) of 3.05 (1.21 to 7.73), 2.83 (1.11 to 7.18), 10.5 (4.32 to 25.6), 2.65 (1.14 to 6.17), 2.49 (1.07 to 5.78) and 2.73 (1.03 to 7.27), respectively. This study did not find a statistically significant association between seropositivity to Toxocara sp. and risk of asthma in children. Low family income, low paternal education level, concomitant allergic rhinitis, family history of asthma and allergic rhinitis and contact with cats were independent factors associated with childhood asthma.

  3. 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

  4. 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

  5. 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

  6. Differences in risk factors of malignancy between men and women with type 2 diabetes: A retrospective case-control study.

    PubMed

    Dąbrowski, Mariusz; Szymańska-Garbacz, Elektra; Miszczyszyn, Zofia; Dereziński, Tadeusz; Czupryniak, Leszek

    2017-09-15

    The aim of this multicenter, retrospective, case-control study was to identify differences in risk factors of malignancy between men and women with type 2 diabetes. Among women the most prevalent malignancies were: breast and uterine cancers (35.6% and 14.4% respectively), while among men there were: colorectal and prostate cancers (24.5% and 13.3% respectively). In both gender metformin use was associated with lower cancer risk. Obesity and insulin treatment in dose-dependent and time-varying manner were associated with significantly increased risk of malignancy in females. In men, unexpectedly, cardiovascular disease was more prevalent in control group. Other variables did not show significant association with malignancy risk. 118 women and 98 men with type 2 diabetes mellitus who developed cancer after diagnosis of diabetes and the same number of strictly age matched controls with type 2 diabetes and without malignancy were included into the study. Diabetes duration, antidiabetic medications use, glycated hemoglobin level, body mass index, smoking habits, occupation, presence of comorbidities and aspirin use were included into analyses. Metformin demonstrated protective effect against cancer in both sexes. Obesity and insulin treatment seem to have greater impact on cancer risk among women.

  7. Increased frequency of hematopoietic malignancies in relatives of patients with lymphoid neoplasms: a French case-control study

    PubMed Central

    Villeneuve, Sara; Orsi, Laurent; Monnereau, Alain; Berthou, Christian; Fenaux, Pierre; Marit, Gerald; Soubeyran, Pierre; Huguet, Françoise; Milpied, Noël; Leporrier, Michel; Hemon, Denis; Troussard, Xavier; Clavel, Jacqueline

    2009-01-01

    Lymphoid neoplasms (LN), including non-Hodgkin’s lymphoma (NHL), Hodgkin’s lymphoma (HL), lymphoproliferative syndrome (LPS) and multiple myeloma (MM), are among the most frequent cancers (approximately 17,000 new cases per year in France), after those related to smoking. LN were investigated using the data from the ENGELA study. ENGELA is a multicenter hospital-based case-control study that was carried out in France over the period September 2000 – December2004. In all, 822 cases (397 NHL, 149 LH, 168 SLP and 108 MM) and 752 controls were included and described 5481 and 5188 first degree relatives, respectively. A positive association with a familial history of hematopoietic cancer was observed for LN (OR = 1.7 [1.0–2.8]) overall and for LPS (OR = 3.2 [1.4–6.8]). The associations with HL (OR = 10.4 [2.0–53.8]) and NHL (OR = 2.4 [1.0–5.9]) were stronger for men. The associations were also stronger when the disease had been diagnosed before the relatives were aged 45 years. The results mainly support the involvement of genetic factors and suggest that at least some of those factors may be sex-linked. However, the slight overrepresentation of affected spouses among the cases might also support the responsibility of environmental factors. PMID:19058175

  8. Management of dental extraction in patients undergoing anticoagulant treatment. Results from a large, multicentre, prospective, case-control study.

    PubMed

    Bacci, Christian; Maglione, Michele; Favero, Lorenzo; Perini, Alessandro; Di Lenarda, Roberto; Berengo, Mario; Zanon, Ezio

    2010-11-01

    Following favourable results from a previous study, a large, multicentre, prospective, case-control study was performed to further assess the incidence of bleeding complications after dental extraction in patients taking oral anticoagulant therapy (OAT). Four hundred fifty-one patients being treated with warfarin who required dental extraction were compared with a control group of 449 non-anticoagulated subjects undergoing the same procedure. In the warfarin-treated group, the oral anticoagulant regimen was maintained unchanged, such that the patients had an International Normalised Ratio ranging between 1.8 and 4, and local haemostatic measures (i.e. fibrin sponges, silk sutures and gauzes saturated with tranexamic acid) were adopted. All the procedures were performed in an outpatient setting. Seven bleeding complications occurred in the OAT group and four in the control group; the difference in the number of bleeding events between the two groups was not statistically significant (OR=1.754; 95% CI 0.510 - 6.034; p=0.3727). No post-operative late bleeds requiring hospitalisation and/or blood transfusions were recorded, and the adjunctive local haemostatic measures were adequate to stop the bleeding. The results of our protocol applied in this large, multicenter study show that dental extractions can be performed easily and safely in anticoagulated outpatients without any modification of the ongoing anticoagulant therapy, thus minimising costs and reducing discomfort for patients.

  9. Increased Risk of Nasopharyngeal Carcinoma with Increasing Levels of Diet-Associated Inflammation in an Italian Case-Control Study.

    PubMed

    Shivappa, Nitin; Hébert, James R; Zucchetto, Antonella; Montella, Maurizio; Libra, Massimo; Garavello, Werner; Rossi, Marta; La Vecchia, Carlo; Serraino, Diego

    2016-10-01

    Components of diet can modulate inflammation and therefore may have an important role in the development of nasopharyngeal carcinoma (NPC). Little is known about the inflammatory potential of diet in relation to nasopharyngeal carcinogenesis. Data from an Italian multicenter case-control study conducted between 1992 and 2008 and including 198 cases with incident, histologically confirmed NPC, and 594 controls hospitalized for acute nonneoplastic diseases were used to estimate the relation between a dietary inflammatory index (DII) and the risk of NPC. The DII was computed based on the intake of selected dietary factors assessed by a validated 78-item food frequency questionnaire. Logistic regression models were used to estimate odds ratios (ORs) adjusted for study center, place of living, sex, age, year of interview, education, tobacco smoking, alcohol drinking, and energy intake using the residual method. Subjects with higher DII scores had an increased risk of NPC, with each DII point increasing risk by nearly 20% [OR: 1.19; 95% confidence interval (CI): 1.05-1.36]. Compared to subjects in the lowest DII tertile, those in the highest tertile had >60% higher risk of NPC (OR: 1.64; 95% CI: 1.06-2.55; Ptrend = 0.04). These results indicate that inflammatory potential of diet plays a role in NPC.

  10. [Case-control study of risk factors associated with constipation. The FREI Study].

    PubMed

    Comas Vives, A; Polanco Allué, I

    2005-04-01

    Children represent one of the patient groups most affected by constipation. Our objective was to identify and describe the risk factors associated with childhood constipation. The study had a case-control, retrospective, open and multicenter design. Clinical data on possible risk factors were collected through an ad-hoc questionnaire. Two groups were studied: children with and without constipation. Nine hundred twenty-one children were recruited; of these, 898 (97.6%) were included in the statistical analysis. There were 408 (45.4%) children in the constipated group and 490 (54.5%) in the non-constipated group. Most of the children with constipation (53.6%) had a maternal history of constipation compared with 21.4% of children without constipation (p < 0.05). More than half (53.2%) of the constipated children reported a lack of regularity in their toilet habits while 64.9 % of the children without constipation went to the toilet regularly. Toilet training started slightly earlier (at 3 years) in children without constipation (93.2%) than in those with the disorder (83.8%) (p < 0.05). At school, 57.4% of the children with constipation never used the toilet compared with 26.8% of those without constipation (p < 0.05). A total of 73.4% of children with constipation drank less than four glasses of water per day compared with 47.1% of those without constipation (p < 0.05). Consumption of vegetables and legumes in the diet was significantly lower in children with constipation than in those without (p < 0.05). The risk factors linked to childhood constipation found in this study were a familial history of constipation, irregular toilet habits, low dietary fiber contents and no fruit intake. The main preventive factors against constipation were water and vegetable consumption and training on the use of the toilet at school. Daily toilet training and dietary changes are needed to prevent constipation among children and to achieve regular defecation. This preventive

  11. 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

  12. Violence against women and gastroschisis: a case-control study.

    PubMed

    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

    2013-10-17

    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. 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). 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.

  13. A case-control study of gastric cancer in Venezuela.

    PubMed

    Muñoz, N; Plummer, M; Vivas, J; Moreno, V; De Sanjosé, S; Lopez, G; Oliver, W

    2001-08-01

    A case-control study to evaluate risk factors for gastric cancer was carried out among 292 cases of gastric cancer and 485 controls in a high-risk area of Venezuela. Subjects were interviewed using a structured questionnaire, which elicited information on residential history, socio-economic status, family history of gastric diseases, smoking, drinking and dietary habits. Habitual diet was estimated from a meal-structured food frequency questionnaire on 75 food items. There was a strong inverse association with social class, as measured by education and by indicators of poverty. The results of the dietary analysis suggest that a diet high in starch and low in meat, fish and fresh vegetables increases risk of gastric cancer. A protective effect was observed for frequent consumption of allium vegetables. Inverse associations were found with height, which may reflect nutritional status in childhood, and with refrigerator use in the first two decades of life. Alcohol and tobacco consumption was investigated among males only, since the prevalence of alcohol and tobacco use was very low in females. Alcohol drinkers were at higher risk than non-drinkers and there was a small excess risk for current smokers compared with never smokers. There was some evidence of familial aggregation of gastric cancer. These findings will have important implications in planning preventive strategies for gastric cancer in Venezuela.

  14. Association between diabetes and tuberculosis: case-control study

    PubMed Central

    Pereira, Susan Martins; de Araújo, Gleide Santos; Santos, Carlos Antônio de Souza Teles; de Oliveira, Maeli Gomes; Barreto, Maurício Lima

    2016-01-01

    ABSTRACT OBJECTIVE To test the association between diabetes and tuberculosis. METHODS It is a case-control study, matched by age and sex. We included 323 new cases of tuberculosis with positive results for bacilloscopy. The controls were 323 respiratory symptomatic patients with negative bacilloscopy, from the same health services, such as: ambulatory cases from three referral hospitals and six basic health units responsible for the notifications of new cases of tuberculosis in Salvador, Bahia. Data collection occurred between 2008 and 2010. The instruments used were structured interview, including clinical data, capillary blood glucose (during fasting or postprandial), and the CAGE questionnaire for screening of abusive consumption of alcohol. Descriptive, exploratory, and multivariate analysis was performed using conditional logistic regression. RESULTS The average age of the cases was 38.5 (SD = 14.2) years and of the controls, 38.5 (SD = 14.3) years. Among cases and controls, most subjects (61%) were male. In univariate analysis we found association between the occurrence of diabetes and tuberculosis (OR = 2.37; 95%CI 1.04–5.42), which remained statistically significant after adjustment for potential confounders (OR = 3.12; 95%CI 1.12–7.94). CONCLUSIONS The association between diabetes and tuberculosis can hinder the control of tuberculosis, contributing to the maintainance of the disease burden. The situation demands increasing early detection of diabetes among people with tuberculosis, in an attempt to improve disease control strategies. PMID:28099656

  15. Baldness and testicular cancer: the EPSAM case-control study.

    PubMed

    Moirano, G; Zugna, D; Grasso, C; Lista, P; Ciuffreda, L; Segnan, N; Merletti, F; Richiardi, L

    2016-03-01

    The etiology of testicular cancer is largely unexplained. Research has mainly focused on prenatal exposures, especially to sex hormones, while less attention has been paid to exposures that may act also postnatally. As baldness has been previously associated with testicular cancer risk we focused on baldness and body hairiness, which are both associated with androgen activity. We used data of the Postnatal Exposures and Male Health (EPSAM) study, a case-control study on testicular cancer conducted in the Province of Turin, Italy, involving cases diagnosed between 1997 and 2008. Information was collected using mailed questionnaires. Analyses included 255 cases and 459 controls. We calculated ORs and 95% CIs to estimate testicular cancer risk among those who developed baldness and among those with body hairiness. We found an inverse association between testicular cancer and baldness (OR: 0.67, 95% CI: 0.46-0.98) and body hairiness (OR: 0.78, 95% CI: 0.53-1.16), although the latter had wider CIs. The inverse association between baldness and testicular cancer is consistent with the results from previous studies. These results suggest that androgens activity may influence testicular cancer risk. © 2016 American Society of Andrology and European Academy of Andrology.

  16. Consanguinity and Neonatal Death: A Nested Case-Control Study

    PubMed Central

    Chaman, Reza; Gholami Taramsari, Mahshid; Khosravi, Ahmad; Amiri, Mohammad; Holakouie Naieni, Kourosh; Yunesian, Masoud

    2014-01-01

    Objective: Although numerous studies have found higher rates of abortion and still births following consanguinity (familial marriages), the question of whether consanguinity significantly increases the risk of neonatal death has inadequately been addressed.This study aims to evaluate familial marriage effects on neonatal death in rural areas in Iran. Materials and methods: In this nested case-control study, 6900 newbornswho were born in rural areas of Kohgiluyeh and Boyerahmad Province (South-West of Iran)were followed till the end of neonatal period, and neonatal death was the outcome of interest. Subsequently 97 cases and 97 controls were selected in study cohort by using risk set sampling model. Crude and adjusted odds ratios (OR) were estimated by usinga conditional logistic regression model. Results: In the final model, prematurity (OR = 5.57), low birthweight (LBW) (OR = 7.68), consanguinity (first cousins) (OR = 5.23), C-section (OR = 7.27), birth rank more than 3 (OR = 6.95) and birthsinterval less than 24 months (OR = 4.65) showed significant statistical association with neonatal mortality (p < 0.05). Conclusion: According to our findings, after adjusting the effects of other significant risk factors, familial marriageto first cousins is considered asan important risk factor for neonatal death. PMID:25530772

  17. Headaches and pineal cyst: a case-control study.

    PubMed

    Seifert, Christian L; Woeller, Andreas; Valet, Michael; Zimmer, Claus; Berthele, Achim; Tölle, Thomas; Sprenger, Till

    2008-03-01

    Pineal cysts have been suggested to be linked to headache pathogenesis. However, no systematic studies on this topic have been performed so far. The aim of this study was to investigate the relationship between pineal cysts and headache and to determine the relevance of the cyst size in this context. We conducted a case-control study of patients who consulted the neurological department between 1999 and 2006 to investigate the relationship between pineal cysts and headache and to determine the relevance of the cyst size. A total of 51 patients with pineal cyst were identified, thereby 51% were suffering from headache (half of them had migraine), whereas in the control group, only 25% had headache (thereof 31% suffered from migraine). There was a significant relationship between headache (as well as migraine) and pineal cysts (chi-square test), but no significant difference in pineal cyst diameter between the patient group with headache versus without headache (t-test). Our data provide evidence for a causal relationship between pineal cysts and headache, respectively, migraine in this patient cohort.

  18. 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

  19. Nutrient patterns and asthenozoospermia: a case-control study.

    PubMed

    Eslamian, G; Amirjannati, N; Rashidkhani, B; Sadeghi, M-R; Hekmatdoost, A

    2017-04-01

    The association of dietary nutrient patterns and sperm motility is not yet well elucidated, and previous studies have just focused on the isolated nutrients. This case-control study examined the association of nutrient patterns with asthenozoospermia among Iranian men. In total, 107 incident asthenozoospermic men and 235 age-matched controls were interviewed through the infertility clinics in Tehran, Iran, from January 2012 to November 2013. Semen quality data were analysed according to the fifth edition of WHO guideline. Nutrient patterns were identified using principal component analysis based on semiquantitative 168-item food frequency questionnaires. All nutrient intakes were energy-adjusted by the residual method. In principal component analysis, three dietary patterns emerged. The first pattern, which was high in vitamin E, vitamin D, vitamin C, zinc, folate, total fibre, selenium and polyunsaturated fatty acids, was significantly associated with lower risk of asthenozoospermia. After adjustment for potential confounders, participants in the highest tertile of the first pattern scores had 51% lower risk of asthenozoospermia compared with those in the lowest (p-trend: .004). Our findings suggest that adherence to the pattern comprising mainly of antioxidant nutrients may be inversely associated with asthenozoospermia.

  20. Determinants of gestational diabetes mellitus: a case-control study.

    PubMed

    Feleke, Berhanu Elfu

    2017-07-09

    Gestational diabetes mellitus (GDM) is glucose intolerance first recognized during pregnancy. The objective of this study was to identify the determinant factors of GDM. An unmatched case-control study was conducted. Descriptive statistics were used to describe the profile of study participants and binary logistic regression was used to identify the determinants of GDM. GDM was associated with history of abortion (AOR 5.05 [95% CI: 2.65-9.63]), family history of diabetes mellitus (AOR 8.63 [95% CI: 5.19-14.35]), chronic hypertension (AOR 4.63 [95% CI: 1.27-16.86]), dietary diversification score (AOR 2.96 [95% CI: 2-4.46]), regular physical exercise (AOR 0.03 [95% CI: 0.01-0.04]), history of infertility (AOR 6.19 [95%CI: 1.86-20.16]), history of Caesarean section (AOR 3.24 [95% CI: 1.58-6.63]), previous history of GDM (AOR 8.21 [95% CI: 3.18-21.24]), previous history of intrauterine fetal death (AOR 3.96 [95% CI: 1.56-10.04]), literacy (AOR 0.6 [95% CI: 0.43-0.85]), body mass index (AOR 2.96 [95% CI: 2.08-4.2]), parity (AOR 1.78 [95% CI: 1.3-2.49]). Regular physical exercise should be used as the main tool in preventing GDM.

  1. Case-control study of a gastroschisis cluster in Nevada.

    PubMed

    Elliott, Leslie; Loomis, Dana; Lottritz, Lisa; Slotnick, Robert Nathan; Oki, Earle; Todd, Randall

    2009-11-01

    To identify potential risk factors associated with a sudden increase in gastroschisis cases in northern Nevada. Case-control study. Medical centers and a pregnancy care center in Reno, Nevada. Participants (n = 14) were women who gave birth to infants with gastroschisis at either of the 2 medical centers in Reno, Nevada, from April 5, 2007, through April 4, 2008. Controls (n = 57) were selected from the same pregnancy center providing perinatal care to the cases and were matched 4:1 to the case mothers by maternal date of birth within 1 year. Environmental exposures and illnesses during pregnancy. Association of gastroschisis with illnesses, medications, or environmental exposures. Gastroschisis was associated with the use of methamphetamine (odds ratio [OR], 7.15; 95% confidence interval [CI], 1.35-37.99) or any vasoconstrictive recreational drug (methamphetamine, amphetamine, cocaine, ecstasy) (OR, 4.46; 95% CI, 1.21-16.44) before pregnancy. When we limited self-reported illnesses to those occurring during the first trimester of pregnancy, chest colds (OR, 16.77; 95% CI, 1.88-150.27) and sore throats (OR, 12.72; 95% CI, 1.32-122.52) were associated with gastroschisis. These findings add strength to the hypothesis that use of methamphetamine and related drugs is a risk factor for gastroschisis and raise questions about the risks associated with infections.

  2. CIGARETTE SMOKING AND MALIGNANT MELANOMA: A CASE-CONTROL STUDY

    PubMed Central

    Kessides, Maria C.; Wheless, Lee; Hoffman-Bolton, Judith; Clipp, Sandra; Alani, Rhoda M.; Alberg, Anthony J.

    2010-01-01

    Background Several previous studies have reported inverse associations between cigarette smoking and melanoma. Often these studies have not adjusted for ultraviolet (UV) exposure history, skin type, or number of blistering sunburns, which could confound the observed associations between cigarette smoking and melanoma. Objective To assess whether this reported inverse association persists after adjusting for UV exposure, skin type, and number of blistering sunburns. Methods We conducted a population-based case-control study (82 melanoma cases, 164 controls). Two controls were matched to each case by age, sex, race, and skin type. Conditional logistic regression models were fit to assess the association between cigarette smoking history and melanoma, with additional adjustments for UV exposure and sunburns. Results Compared to never smokers, both former (OR 0.43, 95% CI 0.18–1.04) and current (OR 0.65, 95% CI 0.19–2.24) smoking were inversely associated with melanoma, but the associations were not statistically significant. Limitations The number of cutaneous nevi was not assessed in this study. Additionally, the relatively small number of cases limits the statistical precision of the observed associations. Conclusions After matching for age, sex, race, and skin type, and further adjusting for UV exposure and number of sunburns, cigarette smoking was not statistically significantly associated with melanoma risk, but the results were consistent with previous observations of an inverse association. PMID:20334951

  3. Periodontal disease and spontaneous preterm birth: a case control study

    PubMed Central

    Wood, Stephen; Frydman, Albert; Cox, Stephen; Brant, Rollin; Needoba, Sheilia; Eley, Barry; Sauve, Reg

    2006-01-01

    Background Several studies have suggested an association between periodontal disease and prematurity but this finding has not been consistently observed. Methods Case control study. Cases (n = 50) were women who had delivered after spontaneous preterm labor at <35 weeks gestation. Two groups of controls (n = 101) were recruited: women who were undelivered but at a preterm gestation and women who delivered at term. A standard, clinical, periodontal examination was performed and gingival crevicular fluid was obtained from standardized locations and tested for neutrophil elastase along with the bacterial enzymes gingipain and dipeptidylpeptidase. Data were analyzed with Fisher's exact tests, ANOVA and multivariate logistic regression. Results There was no difference in the proportion of sites with significant attachment loss (≥3 mm): Cases-3.2%, Controls-2.2% p = 0.21. The gingival crevicular fluid concentrations of elastase and gingipain were elevated in cases vs. controls 238.8 uU/ul vs. 159.6 uU/ul p = .007 and 2.70 uU/ul vs. 1.56 uU/ul p = .001. On multivariate analysis, the mean log concentration of elastase, but not of gingipain, remained a significant predictor of preterm labor p = .0.015. Conclusion We found no evidence that clinical periodontal disease is associated with spontaneous preterm birth. Elevated gingival crevicular fluid levels of elastase were associated with preterm birth but further research is needed before this can be assumed to be a causal relationship. PMID:16848912

  4. Smoking, the environment and meningococcal disease: a case control study.

    PubMed Central

    Stanwell-Smith, R. E.; Stuart, J. M.; Hughes, A. O.; Robinson, P.; Griffin, M. B.; Cartwright, K.

    1994-01-01

    This case control study investigated environmental factors in 74 confirmed cases of meningococcal disease (MD). In children aged under 5, passive smoking in the home (30 or more cigarettes daily) was associated with an odds ratio (OR) of 7.5 (95% confidence interval (CI) 1.46-38.66). ORs increased both with the numbers of cigarettes smoked and with the number of smokers in the household, suggesting a dose-response relationship. MD in this age group was also significantly associated with household overcrowding (more than 1.5 persons per room) (OR 6.0, 95% CI 1.10-32.8), with kisses on the mouth with 4 or more contacts in the previous 2 weeks (OR 2.46, 95% CI 1.09-5.56), with exposure to dust from plaster, brick or stone in the previous 2 weeks (OR 2.24, 95% CI 1.07-4.65); and with changes in residence (OR 3.0, 95% CI 1.0-8.99), marital arguments (OR 3.0, 95% CI 1.26-7.17) and legal disputes in the previous 6 months (OR 3.10, 95% CI 1.24-7.78). These associations were independent of social class. Public health measures to lower the prevalence of cigarette smoking by parents of young children may reduce the incidence of MD. The influence of building dust and stressful life events merits further investigation. PMID:8150006

  5. Nonparametric Bayes modeling for case control studies with many predictors.

    PubMed

    Zhou, Jing; Herring, Amy H; Bhattacharya, Anirban; Olshan, Andrew F; Dunson, David B

    2016-03-01

    It is common in biomedical research to run case-control studies involving high-dimensional predictors, with the main goal being detection of the sparse subset of predictors having a significant association with disease. Usual analyses rely on independent screening, considering each predictor one at a time, or in some cases on logistic regression assuming no interactions. We propose a fundamentally different approach based on a nonparametric Bayesian low rank tensor factorization model for the retrospective likelihood. Our model allows a very flexible structure in characterizing the distribution of multivariate variables as unknown and without any linear assumptions as in logistic regression. Predictors are excluded only if they have no impact on disease risk, either directly or through interactions with other predictors. Hence, we obtain an omnibus approach for screening for important predictors. Computation relies on an efficient Gibbs sampler. The methods are shown to have high power and low false discovery rates in simulation studies, and we consider an application to an epidemiology study of birth defects.

  6. Occupation and breast cancer: a Canadian case-control study.

    PubMed

    Brophy, James T; Keith, Margaret M; Gorey, Kevin M; Luginaah, Isaac; Laukkanen, Ethan; Hellyer, Deborah; Reinhartz, Abraham; Watterson, Andrew; Abu-Zahra, Hakam; Maticka-Tyndale, Eleanor; Schneider, Kenneth; Beck, Matthias; Gilbertson, Michael

    2006-09-01

    A local collaborative process was launched in Windsor, Ontario, Canada to explore the role of occupation as a risk factor for cancer. An initial hypothesis-generating study found an increased risk for breast cancer among women aged 55 years or younger who had ever worked in farming. On the basis of this result, a 2-year case-control study was undertaken to evaluate the lifetime occupational histories of women with breast cancer. The results indicate that women with breast cancer were nearly three times more likely to have worked in agriculture when compared to the controls (OR = 2.80 [95% CI, 1.6-4.8]). The risk for those who worked in agriculture and subsequently worked in automotive-related manufacturing was further elevated (OR = 4.0 [95% CI, 1.7-9.9]). The risk for those employed in agriculture and subsequently employed in health care was also elevated (OR = 2.3 [95% CI, 1.1-4.6]). Farming tended to be among the earlier jobs worked, often during adolescence. While this article has limitations including the small sample size and the lack of information regarding specific exposures, it does provide evidence of a possible association between farming and breast cancer. The findings indicate the need for further study to determine which aspects of farming may be of biological importance and to better understand the significance of timing of exposure in terms of cancer risk.

  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. The Misconception of Case-Control Studies in the Plastic Surgery Literature: A Literature Audit.

    PubMed

    Hatchell, Alexandra C; Farrokhyar, Forough; Choi, Matthew

    2017-06-01

    Case-control study designs are commonly used. However, many published case-control studies are not true case-controls and are in fact mislabeled. The purpose of this study was to identify all case-control studies published in the top three plastic surgery journals over the past 10 years, assess which were truly case-control studies, clarify the actual design of the articles, and address common misconceptions. MEDLINE, Embase, and Web of Science databases were searched for case-control studies in the three highest-impact factor plastic surgery journals (2005 to 2015). Two independent reviewers screened the resulting titles, abstracts, and methods, if applicable, to identify articles labeled as case-control studies. These articles were appraised and classified as true case-control studies or non-case-control studies. The authors found 28 articles labeled as case-control studies. However, only six of these articles (21 percent) were truly case-control designs. Of the 22 incorrectly labeled studies, one (5 percent) was a randomized controlled trial, three (14 percent) were nonrandomized trials, two (9 percent) were prospective comparative cohort designs, 14 (64 percent) were retrospective comparative cohort designs, and two (9 percent) were cross-sectional designs. The mislabeling was worse in recent years, despite increases in evidence-based medicine awareness. The majority of published case-control studies are not in fact case-control studies. This misunderstanding is worsening with time. Most of these studies are actually comparative cohort designs. However, some studies are truly clinical trials and thus a higher level of evidence than originally proposed.

  9. Risk factors for syphilis in women: case-control study

    PubMed Central

    de Macêdo, Vilma Costa; de Lira, Pedro Israel Cabral; de Frias, Paulo Germano; Romaguera, Luciana Maria Delgado; Caires, Silvana de Fátima Ferreira; Ximenes, Ricardo Arraes de Alencar

    2017-01-01

    ABSTRACT OBJECTIVE To determine the sociodemographic, behavioral, and health care factors related to the occurrence of syphilis in women treated at public maternity hospitals. METHODS This is a case-control study (239 cases and 322 controls) with women admitted to seven maternity hospitals in the municipality of Recife, Brazil, from July 2013 to July 2014. Eligible women were recruited after the result of the VDRL (Venereal Disease Research Laboratory) under any titration. The selection of cases and controls was based on the result of the serology for syphilis using ELISA (enzyme-linked immunosorbent assay). The independent variables were grouped into: sociodemographic, behavioral, clinical and obstetric history, and health care in prenatal care and maternity hospital. Information was obtained by interview, during hospitalization, with the application of a questionnaire. Odds ratios and 95% confidence intervals were estimated using logistic regression to identify the predicting factors of the variable to be explained. RESULTS The logistic regression analysis identified as determinant factors for gestational syphilis: education level of incomplete basic education or illiterate (OR = 2.02), lack of access to telephone (OR = 2.4), catholic religion (OR = 1.70 ), four or more pregnancies (OR = 2.2), three or more sexual partners in the last year (OR = 3.1), use of illicit drugs before the age of 18 (OR = 3.0), and use of illicit drugs by the current partner (OR = 1.7). Only one to three prenatal appointments (OR = 3.5) and a previous history of sexually transmitted infection (OR = 9.7) were also identified as determinant factors. CONCLUSIONS Sociodemographic, behavioral, and health care factors are associated with the occurrence of syphilis in women and should be taken into account in the elaboration of universal strategies aimed at the prevention and control of syphilis, but with a focus on situations of greater vulnerability. PMID:28832758

  10. Toxocariasis in Waste Pickers: A Case Control Seroprevalence Study

    PubMed Central

    Alvarado-Esquivel, Cosme

    2013-01-01

    Background The epidemiology of Toxocara infection in humans in Mexico has been poorly explored. There is a lack of information about Toxocara infection in waste pickers. Aims Determine the seroepidemiology of Toxocara infection in waste pickers. Methods Through a case control study design, the presence of anti-Toxocara IgG antibodies was determined in 90 waste pickers and 90 age- and gender-matched controls using an enzyme-linked immunoassay. Associations of Toxocara exposure with socio-demographic, work, clinical, and behavioral data of the waste pickers were also evaluated. Results The seroprevalence of anti-Toxocara IgG antibodies was significantly higher in waste pickers (12/90: 13%) than in control subjects (1/90: 1%) (OR  = 14; 95% CI: 2–288). The seroprevalence was not influenced by socio-demographic or work characteristics. In contrast, increased seroprevalence was found in waste pickers suffering from gastritis, and reflex and visual impairments. Multivariate analysis showed that Toxocara exposure was associated with a low frequency of eating out of home (OR  = 26; 95% CI: 2–363) and negatively associated with consumption of chicken meat (OR  = 0.03; 95% CI: 0.003–0.59). Other behavioral characteristics such as animal contacts or exposure to soil were not associated with Toxocara seropositivity. Conclusions 1) Waste pickers are a risk group for Toxocara infection. 2) Toxocara is impacting the health of waste pickers. This is the first report of Toxocara exposure in waste pickers and of associations of gastritis and reflex impairment with Toxocara seropositivity. Results warrant for further research. PMID:23349987

  11. Zinc status in febrile seizure: a case-control study.

    PubMed

    Salehiomran, Mohammad Reza; Mahzari, Masoumeh

    2013-01-01

    Febrile seizure is the most common type of seizure in children. Their incidence is 2-5%. There are different hypotheses about relationship between neurotransmitters and trace elements (such as zinc) and febrile seizure. Zinc, as a major element of some enzymes, plays an important role in the central nervous system (CNS) and can affect some inhibitory mechanisms of CNS. The aim of the present study was to determine whether there were any changes in serum zinc level in children with febrile seizure in comparison with febrile children without seizure. This case-control study was performed on 100 patients aged 6 months to 6 years. This study was conducted between January and August 2012, on 50 children with febrile seizures (case) and 50 febrile children without seizures (control), that were referred to Amirkola Children Hospital (a referral hospital in the north of Iran). Two groups were matched for age and sex. The serum zinc levels in the both groups were determined by atomic absorption spectrophotometry method. The mean serum zinc level was 0.585±0.166 mg/L and 0.704±0.179 mg/L in the case group and the control group, respectively (p=0.001). The mean serum zinc level was significantly lower in the febrile seizure group compared to the control groups. Our findings revealed that serum zinc level was significantly lower in children with simple febrile seizure in comparison with febrile children without seizure. It can emphasize the hypothesis that there is a relation between serum zinc level and febrile seizure in children.

  12. Dermatological indicators of coronary risk: a case-control study.

    PubMed

    Mirić, D; Fabijanić, D; Giunio, L; Eterović, D; Culić, V; Bozić, I; Hozo, I

    1998-12-31

    We examined the association of dermatological signs such as baldness, thoracic hairiness, hair greying and diagonal earlobe crease with the risk of myocardial infarction in men under the age of 60 years. A hospital-based, case-control study included 842 men admitted for the first non-fatal myocardial infarction, the controls were 712 men admitted with noncardiac diagnoses, without clinical signs of coronary disease. The relative risks were estimated as odds ratios. Logistic regression was used to control for the confounding variables. Baldness, thoracic hairiness and earlobe crease were approximately 40% more prevalent in cases (P<10(-6) in each case). In both cases and controls, baldness and thoracic hairiness were frequently coexistent, as well as hair greying and earlobe crease (P<10(-4) in each case). After allowing for age and other established coronary risk factors, the relative risk of myocardial infarction for fronto-parietal baldness compared with no hair loss was 1.77 (95% CI 1.27-2.45) and it was 1.83 (95 CI 1.4-2.3) for men with thick, extended thoracic hairiness. The presence of a diagonal earlobe crease yielded a relative risk of 1.37 (95% CI 1.25-1.5), while hair greying was associated with myocardial infarction only in men under the age of 50 years. It appears that baldness, thoracic hairiness and diagonal earlobe crease indicate an additional risk of myocardial infarction in men under the age of 60 years, independently of age and other established coronary risk factors.

  13. Snow sports injuries in Scotland: a case-control study

    PubMed Central

    Langran, M; Selvaraj, S

    2002-01-01

    Objectives: To examine the incidence and patterns of snow sports injuries at the three largest commercial ski areas in Scotland and to identify factors associated with injury risk. Methods: A prospective case-control study of all injured people at Cairngorm, Glenshee, and Nevis Range ski areas during the 1999–2000 winter season. Personal details, snow sports related variables, diagnosis, and treatment were recorded. Control data were collected at random from uninjured people at all three areas. Random counts were performed to analyse the composition of the on slope population. Results: A total of 732 injuries were recorded in 674 people. Control data were collected from 336 people. The injury rate for the study was 3.7 injuries per 1000 skier days. Alpine skiers comprised 67% of the on slope population, snowboarders 26%, skiboarders 4%, and telemark skiers 2%. Lower limb injuries and sprains were the commonest injuries in alpine skiers and skiboarders. Snowboarders sustained more injuries to the upper limb and axial areas. Skiboarders and snowboarders had a higher incidence of fractures. After adjustment for other variables, three factors were all independently associated with injury: snowboarding (odds ratio (OR) 4.07, 95% confidence interval (CI) 1.65 to 10.08), alpine skiing (OR 3.82, CI 1.6 to 9.13), and age <16 years (OR 1.9, CI 1.14 to 3.17). More than five days of experience in the current season and at least one week of experience in total had a protective effect against injury. Conclusions: Despite a change in the composition of the alpine population at Scottish ski areas, the overall rate and pattern of injury are similar to those reported previously in comparable studies. Several factors are associated with an increased risk of injury and should be targeted in future injury prevention campaigns. PMID:11916898

  14. Facial dermatosis associated with Demodex: a case-control study.

    PubMed

    Zhao, Ya-e; Peng, Yan; Wang, Xiang-lan; Wu, Li-ping; Wang, Mei; Yan, Hu-ling; Xiao, Sheng-xiang

    2011-12-01

    Demodex has been considered to be related with multiple skin disorders, but controversy persists. In this case-control study, a survey was conducted with 860 dermatosis patients aged 12 to 84 years in Xi'an, China to identify the association between facial dermatosis and Demodex. Amongst the patients, 539 suffered from facial dermatosis and 321 suffered from non-facial dermatosis. Demodex mites were sampled and examined using the skin pressurization method. Multivariate regression analysis was applied to analyze the association between facial dermatosis and Demodex infestation, and to identify the risk factors of Demodex infestation. The results showed that total detection rate of Demodex was 43.0%. Patients aged above 30 years had higher odds of Demodex infestation than those under 30 years. Compared to patients with neutral skin, patients with mixed, oily, or dry skin were more likely to be infested with Demodex (odds ratios (ORs) were 2.5, 2.4, and 1.6, respectively). Moreover, Demodex infestation was found to be statistically associated with rosacea (OR=8.1), steroid-induced dermatitis (OR=2.7), seborrheic dermatitis (OR=2.2), and primary irritation dermatitis (OR=2.1). In particular, ORs calculated from the severe infestation (≥5 mites/cm(2)) rate were significantly higher than those of the total rate. Therefore, we concluded that Demodex is associated with rosacea, steroid-induced dermatitis, seborrheic dermatitis, and primary irritation dermatitis. The rate of severe infestation is found to be more correlated with various dermatosis than the total infestation rate. The risk factors of Demodex infestation, age, and skin types were identified. Our study also suggested that good hygiene practice might reduce the chances of demodicosis and Demodex infestation.

  15. Hyperhomocysteinemia among Omani autistic children: a case-control study.

    PubMed

    Ali, Amanat; Waly, Mostafa I; Al-Farsi, Yahya M; Essa, Musthafa M; Al-Sharbati, Marwan M; Deth, Richard C

    2011-01-01

    High serum homocysteine (Hcy) level is regarded as an indicator for impairment of folate-dependent methionine cycle and is associated with oxidative stress. In a case control study, we evaluated eighty 3-5 years old Omani children (40 diagnosed with Autism Spectrum Disorder and 40 their age and gender matched controls) for their fasting serum homocysteine levels as a biomarker of Autism Spectrum Disorder (ASD). Serum folate and vitamin B(12) status were also evaluated. The serum homocysteine was measured using an enzyme immunoassay (EIA) technique whereas folate and vitamin B(12) were measured using an automated random access immune-assay system. The results indicated that mean serum Hcy levels were significantly (P < 0.05) higher in autistic children (20.1 ± 3.3 µmol/L) as compared to controls (9.64 ± 2.1 µmol/L). Significantly (P < 0.05) lower serum folate (1.8 ± 0.4 µg/L) and vitamin B(12) (191.1 ± 0.9 pg/mL) levels were observed in autistic children as compared to controls (6.1 ± 0.6 µg/L and 288.9 ± 1.3 pg/mL, respectively). The levels of homocysteine in autistic children were also much higher as compared to normal reference values (5-15 µmol/L). The results suggest that high fasting serum homocysteine and low folate and vitamin B(12) levels could be used as clinical biomarkers for an early diagnosis and management of ASD.

  16. Female sexual dysfunction in androgenetic alopecia: Case-control study

    PubMed Central

    Sancak, Eyup Burak; Oguz, Sevilay; Akbulut, Tugba; Uludag, Aysegul; Akbas, Alpaslan; Kurt, Omer; Akbulut, Mehmet Fatih

    2016-01-01

    Introduction: We sought to evaluate the association of female sexual dysfunction (FSD) with androgenetic alopecia (AGA) and metabolic syndrome (MetS) in premenopausal women. Methods: From December 2013 to June 2015, we performed a case-control, prospective study of 115 patients with AGA and 97 age-matched control patients without AGA from among premenopausal women who visited dermatology clinics of the two reference hospitals. Comprehensive history, anthropometric measurements, and questionnaire administration were performed for each of the total of 212 women. The Female Sexual Function Index (FSFI) was used to assess the key dimensions of female sexual function. AGA was assessed and graded by an experienced dermatologist according to Ludwig’s classification. The MetS assessment was made according to the NCEP-ATP III criteria. Results: In univariate analysis, age, weight, waist circumference, hip circumference, waist-to-hip ratio, body mass index (BMI), AGA, MetS, cardiovascular event, marital status, hypertension, high fasting plasma glucose, high triglyceride, large waist, total testosterone, and free testosterone were associated with presence of FSD. In logistic regression analysis, age (odds ratio [OR] 1.21, 95% confidence interval [CI] 1.13–1.30; p<0.001), AGA (OR 3.42, 95% CI 1.31–8.94; p=0.017), MetS (OR 5.39, 95% CI 1.34–21.62; p=0.012), and free testosterone (OR 0.18, 95% CI 0.09–0.37; p<0.001) were independently associated with FSD. Conclusions: Our study suggests that age, AGA, MetS, and free testosterone may have strong impact on sexual function in premenopausal women. Further studies with population-based and longitudinal design should be conducted to confirm this finding. PMID:28255417

  17. 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

  18. 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.

  19. [Risk factors associated with preeclampsia: case-control study].

    PubMed

    Morgan-Ortiz, Fred; Calderón-Lara, Sergio Alberto; Martínez-Félix, Jesús Israel; González-Beltrán, Aurelio; Quevedo-Castro, Everardo

    2010-03-01

    Preeclampsia is one of the most frequent and serious complication of pregnancy characterized by systemic perfusion reduction generated by vasospasm and activation of coagulation systems. To evaluate the association between preeclampsia sociodemographics and obstetrics antecedents. An unmatched case-control study was carried out in which all the clinical registries of patients with preeclampsia (cases: n = 196) assisted in the period 2003-2007 in the Hospital Civil of Culiacan, Sinaloa State of Mexico were analyzed. As controls the clinical registries of patients assisted during the same period were selected at random but that they didn't show up preeclampsia (n = 470). The association of preeclampsia with socioeconomic level, tobacco use, alcohol use, gynecologic and obstetric antecedents (sexual partners, pregnancies, deliveries and abortions number, prenatal control, contraceptive method) and previous pregnancy with preeclampsia were analyzed. There were not association between tobacco use (OR: 3.05; 95% CI: 0.81-11.48), beginning of sexual activity (p = 0.1509), number of sexual partners (OR: 1.23; 95% CI: 0.83-1.83; p = 0.3009) and sexual cohabitation less than 12 months (OR: 0.90; 95% CI: 0.63-1.27). The alcoholism (OR: 5.77; 95% CI: 1.48-22.53), socioeconomic level (p < 0.05), pregnancy previous with preeclampsia (RM:14.81; 95% CI: 1.77-123.85; p = 0.0006) were associated with preeclampsia. There were differences in the use of the contraceptive method between groups (p < 0.005). Preeclampsia was significantly associated with the alcoholism, low socioeconomic level and pregnancy previous with preeclampsia.

  20. [Risk factors associated with trigger finger. Case-control study].

    PubMed

    De la Parra-Márquez, Miguel Leonardo; Tamez-Cavazos, Roberto; Zertuche-Cedillo, Luis; Martínez-Pérez, Juan José; Velasco-Rodríguez, Víctor; Cisneros-Pérez, Vicente

    2008-01-01

    We undertook this study to identify risk factors in our population associated with trigger finger. The study was conducted at the Instituto Mexicano del Seguro Social, UMAE 21, Monterrey, Nuevo Leon, Mexico. This was a case-control, retrospective, and observational study. There were 250 patients in each group. For cases, patients who were operated on for trigger finger from March 2006 to August 2006 were included. Controls included patients admitted to the Emergency Department with hand injuries that fulfilled the selection criteria. Risk factors analyzed were diabetes, hypertension, smoking, sex, age, weight, and 19 different occupations. Mean age of the cases was 52 years (SE +/- 14.19 years) with a median and mode of 53 years. The right hand was the most common with the middle, thumb, ring, index and little fingers, respectively. A significant statistical relationship was found: females (OR 7.57, 95% CI 5.07-11.31); diabetes (OR 3.72, 95% CI 2.43-5.70); obesity (OR 1.49, 95% CI 1.02-2.19). With regard to occupation, a statistical relationship was found: homemaker (OR 2.44, 95% CI 1.62-3.69); seamstress (OR 4.8, 95% CI 1.3-21.6); and secretary (OR 2.74, 95% CI 1.38-5.52). Trigger finger is a common pathology in our population and is more frequent in women >53 years old. It may be related to diabetes, body mass index (obesity) and certain occupations such as secretary, seamstress and homemaker.

  1. Childhood trauma in multiple sclerosis: a case-control study.

    PubMed

    Spitzer, Carsten; Bouchain, Miriam; Winkler, Liza Y; Wingenfeld, Katja; Gold, Stefan M; Grabe, Hans Joergen; Barnow, Sven; Otte, Christian; Heesen, Christoph

    2012-04-01

    To investigate the association between childhood trauma and multiple sclerosis (MS) by comparing histories of child abuse and neglect between patients with MS and adults from the general population in a cross-sectional case-control study. Previous research has demonstrated a connection between MS and a variety of emotional stressors, but childhood trauma, which is known to have long-lasting negative consequences for physical health decades into adulthood, has not been studied. The self-reported Childhood Trauma Questionnaire for the assessment of emotional, physical, and sexual abuse and emotional and physical neglect was administered to 234 patients with definite MS and 885 adults from the general population. After adjusting for sociodemographic factors and current depression, patients with MS scored significantly higher in all Childhood Trauma Questionnaire subscales apart from physical abuse and neglect than adults from the general population. Adjusted odds ratios for these types of childhood trauma were higher in the MS group than in controls, ranging from 2.0 for emotional neglect (95% confidence interval = 1.3-3.2) to 3.4 for emotional abuse (95% confidence interval = 2.0-5.7). Although childhood trauma was not associated with the degree of current MS-related disability, patients with MS with histories of physical and/or sexual abuse had significantly higher relapse rates than patients without early-life stress. Our findings suggest an association between childhood trauma and MS in this cross-sectional study. Larger prospective longitudinal studies are needed to clarify the relationship between early-life stress and the risk for MS in genetically susceptible individuals.

  2. Surgical site infections in breast surgery: case-control study.

    PubMed

    Vilar-Compte, Diana; Jacquemin, Benedicte; Robles-Vidal, Carlos; Volkow, Patricia

    2004-03-01

    The purpose of this study was to estimate the frequency of surgical site infections (SSIs) and identify associated risk factors for each type of breast surgery at a cancer hospital. We used a nested case-control design. Between February 1, 2000 and July 31, 2000, all breast surgeries performed were recorded on a daily basis. After hospital discharge, we evaluated patients simultaneously with surgeons three times a week for 30 days or longer. The odds ratio (OR) was estimated using logistic regression analysis. The study followed 280 patients (298 wounds). Altogether, 77 SSIs were detected, for an overall SSI rate of 25.8% (77/298). For excisions, conservative surgery, and radical mastectomies the SSI rates were 1.4%, 18.0%, and 38.3%, respectively. Excisions were excluded ( n = 68) for risk factor analysis. After multivariate analysis, risk factors associated with SSIs were obesity [OR 2.5, 95% confidence interval (CI) 1.2-4.3], concomitant chemotherapy and radiation (OR 2.3, 95% CI 1.2-4.3), radical surgery (OR 3.1, 95% CI 1.1-8.6), insertion of a second drain during the late postoperative period (OR 3.7, 95% CI 1.8-7.8), and drainage duration > or = 19 days (OR 2.9, 95% CI 1.5-5.6). The bacteria most frequently isolated were Pseudomonas aeruginosa ( n = 18 ), Serratia sp. ( n = 18), Staphylococcus aureus ( n = 10), and Staphylococcus epidermidis ( n = 10). Poor compliance with infection control practices and wound management was detected throughout the study period. The overall frequency of SSIs for mastectomies was higher than the reported rates, which was principally related to the more radical surgery required for advanced-stage disease, preoperative irradiation, and inadequate wound and drain care.

  3. Case-control analysis of paternal age and trisomic anomalies.

    PubMed

    De Souza, E; Morris, J K

    2010-11-01

    To determine whether older paternal age increases the risk of fathering a pregnancy with Patau (trisomy 13), Edwards (trisomy 18), Klinefelter (XXY) or XYY syndrome. Case-control: cases with each of these syndromes were matched to four controls with Down syndrome from within the same congenital anomaly register and with maternal age within 6 months. Data from 22 EUROCAT congenital anomaly registers in 12 European countries. Diagnoses with observed or (for terminations) predicted year of birth from 1980 to 2005, comprising live births, fetal deaths with gestational age ≥ 20 weeks and terminations after prenatal diagnosis of the anomaly. Data include 374 cases of Patau syndrome, 929 of Edwards syndrome, 295 of Klinefelter syndrome, 28 of XYY syndrome and 5627 controls with Down syndrome. Odds ratio (OR) associated with a 10-year increase in paternal age for each anomaly was estimated using conditional logistic regression. Results were adjusted to take account of the estimated association of paternal age with Down syndrome (1.11; 95% CI 1.01 to 1.23). The OR for Patau syndrome was 1.10 (95% CI 0.83 to 1.45); for Edwards syndrome, 1.15 (0.96 to 1.38); for Klinefelter syndrome, 1.35 (1.02 to 1.79); and for XYY syndrome, 1.99 (0.75 to 5.26). There was a statistically significant increase in the odds of Klinefelter syndrome with increasing paternal age. The larger positive associations of Klinefelter and XYY syndromes with paternal age compared with Patau and Edwards syndromes are consistent with the greater percentage of these sex chromosome anomalies being of paternal origin.

  4. 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

  5. [Oxidative stress and longevity; a case-control study].

    PubMed

    Belenguer Varea, Ángel; Mohamed Abdelaziz, Kheira; Avellana Zaragoza, Juan Antonio; Borrás Blasco, Consuelo; Sanchis Aguilar, Paula; Viña Ribes, José

    2015-01-01

    Human longevity is a complex issue influenced by genetic and environmental factors. Oxidative stress (OE) could play an important role in this process. Succesful aging could be related with the organism ability facing OE. In the present study we compared malondialdehyde (MDA) and oxidized proteins (OP) plasma levels, in elderly people older than 97 years and 70-80 years old, to better understand the effects of OE on human longevity. Population-based case control study. We considered as cases patients who were born and live on la Ribera county in Valencia (Spain) older than 97 years old and who accepted to participate in the study. Controls were from the same poblational base, chosen randomly, and 70-80 years old. We made a descriptive analysis of sociodemographic, clinic and functional variables; an odds ratio (OR) estimation of being centenarian by OP and MDA quartiles; and a tendency analysis by Mantel-Haenszel test. Twenty eight cases and 31 controls were included. Functional state and robust percentage were worse in cases. MDA (1,44±0,45 vs 1,84±0,59, p=0,005), and OP (64,29±15,73 vs. 76,52±13,44, p=0,002) levels, were significantly lower in cases. The OR of being centenarian in lower/higher quartile were 3,8 for MDA and 5,7 for OP, with a Mantel-Haenszel signification of 0,029 and 0,044 respectively. In our study OE level were lower in centenarians than in younger elderly, and the lower the OE grade, the higher were the likelihood of being centenarian. Copyright © 2014. Published by Elsevier Espana.

  6. 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

  7. Comorbidities in rotator cuff disease: a case-control study.

    PubMed

    Titchener, Andrew G; White, Jonathan J E; Hinchliffe, Sally R; Tambe, Amol A; Hubbard, Richard B; Clark, David I

    2014-09-01

    Rotator cuff disease is a common condition in the general population, but relatively little is known about its associated risk factors. We have undertaken a large case-control study using The Health Improvement Network database to assess and to quantify the relative contributions of some constitutional and environmental risk factors for rotator cuff disease in the community. Our data set included 5000 patients with rotator cuff disease who were individually matched with a single control by age, sex, and general practice (primary care practice). The median age at diagnosis was 55 years (interquartile range, 44-65 years). Multivariate analysis showed that the risk factors associated with rotator cuff disease were Achilles tendinitis (odds ratio [OR] = 1.78), trigger finger (OR = 1.99), lateral epicondylitis (OR = 1.71), and carpal tunnel syndrome (OR = 1.55). Oral corticosteroid therapy (OR = 2.03), oral antidiabetic use (OR = 1.66), insulin use (OR = 1.77), and "overweight" body mass index of 25.1 to 30 (OR = 1.15) were also significantly associated. Current or previous smoking history, body mass index of greater than 30, any alcohol intake, medial epicondylitis, de Quervain syndrome, cubital tunnel syndrome, and rheumatoid arthritis were not found to be associated with rotator cuff disease. We have identified a number of comorbidities and risk factors for rotator cuff disease. These include lateral epicondylitis, carpal tunnel syndrome, trigger finger, Achilles tendinitis, oral corticosteroid use, and diabetes mellitus. The findings should alert the clinician to comorbid pathologic processes and guide future research into the etiology of this condition. Copyright © 2014 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

  8. Tumor diagnosis preceding Parkinson's disease: a case-control study.

    PubMed

    D'Amelio, Marco; Ragonese, Paolo; Morgante, Letterio; Epifanio, Antonio; Callari, Graziella; Salemi, Giuseppe; Savettieri, Giovanni

    2004-07-01

    Lower cancer risk in Parkinson's disease (PD) patients compared to the general population has been reported. However, most of the studies were based on death certificates. We designed a case-control study to estimate the association of tumor preceding PD onset and PD. PD patients were matched by age and gender to PD-free individuals, randomly selected from the municipalities of residence of cases. Occurrence of tumors preceding PD onset was assessed through a structured questionnaire. Neoplasms were categorized as benign, malignant, or of uncertain classification, and endocrine-related or not. Odds ratios (OR) were calculated using conditional logistic regression and adjusted for tumor categories and risk factors. We included 222 PD patients. Frequency of cancer was 6.8% for cases, 12.6% for controls. PD patients had a decreased risk for neoplasms (adjusted OR, 0.4; 95% confidence interval [CI], 0.2-0.7). Risk was reduced only for women (adjusted OR, 0.3; 95% CI, 0.1-0.7). PD patients had a decreased risk both for malignant (adjusted OR, 0.6; 95% CI, 0.1-2.5) and nonmalignant neoplasms (adjusted OR, 0.3; 95% CI, 0.1-0.7). Still, risk was decreased for endocrine-related tumors (adjusted OR, 0.3; 95% CI, 0.1-0.9) and non-endocrine-related tumors (adjusted OR, 0.4; 95% CI, 0.1-0.9). Our study confirms the inverse association between PD and neoplasms reported in previous epidemiologic studies.

  9. Haematopoietic cancer and medical history: a multicentre case control study

    PubMed Central

    Vineis, P.; Crosignani, P.; Sacerdote, C.; Fontana, A.; Masala, G.; Miligi, L.; Nanni, O.; Ramazzotti, V.; Rodella, S.; Stagnaro, E.; Tumino, R.; Vigano, C.; Vindigni, C.; Costantini, A. S.

    2000-01-01

    BACKGROUND—Viruses (such as Epstein-Barr virus) and pathological conditions (mainly involving immunosuppression) have been shown to increase the risk of haematolymphopoietic malignancies. Other associations (diabetes, tonsillectomy, autoimmune diseases) have been inconsistently reported.
METHODS—The association between different haematolymphopoietic malignancies (lymphomas, myelomas and leukaemias) and the previous medical history has been studied in a population-based case-control investigation conducted in Italy, based on face to face interviews to 2669 cases and 1718 population controls (refusal rates 10% and 19%, respectively). Controls were a random sample of the general population.
RESULTS—Previous findings were confirmed concerning the association between non-Hodgkin's lymphoma (NHL) and lupus erythematosus (odds ratio, OR=8.4; 95% CI 1.6, 45), tuberculosis (OR=1.6; 1.05, 2.5) and hepatitis (1.8; 1.4, 2.3). An association was found also between NHL and maternal (OR=2.8; 1.1, 6.9) or paternal tuberculosis (OR=1.7; 0.7, 3.9). Odds ratios of 4.0 (1.4, 11.8) and 4.4 (1.1, 6.6) were detected for the association between NHL and Hodgkin's disease, respectively, and previous infectious mononucleosis, but recall bias cannot be ruled out. No association was found with diabetes, tonsillectomy and adenoidectomy. An association with malaria at young age and "low grade" lymphatic malignancies is suggested. One interesting finding was the observation of four cases of poliomyelitis among NHL patients, one among Hodgkin's disease and one among myeloid leukaemia patients, compared with none among the controls (Fisher's exact test for NHL and Hodgkin's disease, p= 0.03, one tail).
CONCLUSIONS—Some of these findings are confirmatory of previous evidence. Other observations, such as the putative role of the polio virus and of malaria are new. A unifying theory on the mechanisms by which previous medical history may increase the risk of

  10. Acromegalic axial arthropathy: a clinical case-control study.

    PubMed

    Scarpa, Raffaele; De Brasi, Davide; Pivonello, Rosario; Marzullo, Paolo; Manguso, Francesco; Sodano, Antonio; Oriente, Pasquale; Lombardi, Gaetano; Colao, Annamaria

    2004-02-01

    Arthropathy is the major cause of morbidity in acromegaly. To feature the spinal involvement, 54 patients with active acromegaly (27 men, 27 women; age range, 21-69 yr) and 54 sex-, age-, and body mass index-matched healthy controls were enrolled in this observational analytical prospective case-control study. A questionnaire to describe onset, duration, and severity of articular symptoms; rheumatological examination, including vertebral and chest mobility, Schober test, thorax expansion, and axial radiological study; and IGF-I, GH, insulin, and glucose level measurement (baseline and after an oral glucose tolerance test) was used to investigate the prevalence of arthropathy and correlate these findings with hormonal parameters. Axial arthropathy was found in 28 patients (52%) and 12 controls (22%; chi(2) = 8.9; P = 0.003). In detail, spinal mobility was reduced in 30 patients (56%) and 10 controls (18%; chi(2) = 14.3; P < 0.0001), thoracic cage was involved in six patients (11%), alterations of spinal profile were observed in 37 patients (68%) and 15 controls (28%; chi(2) = 16.3; P < 0.0001), and increased L2 vertebra diameters were observed in 34 patients (63%) and none of the controls (chi(2) = 46.7; P < 0.0001). Narrowing and widening of L2-L3 disk space were found in 20 (37%) and seven (13%) patients, respectively. Features of diffuse idiopathic skeletal hyperostosis (DISH) were found in 11 patients (20%) and none of the controls (chi(2) = 10.1; P < 0.001). Disease duration was correlated with vertebral body height (P = 0.001) or intervertebral space height (P = 0.02), and lumbar mobility with thorax expansion (P = 0.004); DISH severity was correlated with basal (P = 0.04) and peak (P = 0.01) glucose levels after glucose load. In conclusion, chronic GH and IGF-I excess typically affects the axial skeleton with development of severe alterations of spine morphology and function until features of DISH occur. An early diagnosis of acromegaly is mandatory to reduce

  11. Spatial Analysis of Childhood Cancer: A Case/Control Study

    PubMed Central

    Ramis, Rebeca; Gómez-Barroso, Diana; Tamayo, Ibon; García-Pérez, Javier; Morales, Antonio; Pardo Romaguera, Elena; López-Abente, Gonzalo

    2015-01-01

    Background Childhood cancer was the leading cause of death among children aged 1-14 years for 2012 in Spain. Leukemia has the highest incidence, followed by tumors of the central nervous system (CNS) and lymphomas (Hodgkin lymphoma, HL, and Non-Hodgkin’s lymphoma, NHL). Spatial distribution of childhood cancer cases has been under concern with the aim of identifying potential risk factors. Objective The two objectives are to study overall spatial clustering and cluster detection of cases of the three main childhood cancer causes, looking to increase etiological knowledge. Methods We ran a case-control study. The cases were children aged 0 to 14 diagnosed with leukemia, lymphomas (HL and NHL) or CNS neoplasm in five Spanish regions for the period 1996-2011. As a control group, we used a sample from the Birth Registry matching every case by year of birth, autonomous region of residence and sex with six controls. We geocoded and validated the address of the cases and controls. For our two objectives we used two different methodologies. For the first, for overall spatial clustering detection, we used the differences of K functions from the spatial point patterns perspective proposed by Diggle and Chetwynd and the second, for cluster detection, we used the spatial scan statistic proposed by Kulldorff with a level for statistical significance of 0.05. Results We had 1062 cases of leukemia, 714 cases of CNS, 92 of HL and 246 of NHL. Accordingly we had 6 times the number of controls, 6372 controls for leukemia, 4284 controls for CNS, 552 controls for HL and 1476 controls for NHL. We found variations in the estimated empirical D(s) for the different regions and cancers, including some overall spatial clustering for specific regions and distances. We did not find statistically significant clusters. Conclusions The variations in the estimated empirical D(s) for the different regions and cancers could be partially explained by the differences in the spatial distribution of

  12. Spatial analysis of childhood cancer: a case/control study.

    PubMed

    Ramis, Rebeca; Gómez-Barroso, Diana; Tamayo, Ibon; García-Pérez, Javier; Morales, Antonio; Pardo Romaguera, Elena; López-Abente, Gonzalo

    2015-01-01

    Childhood cancer was the leading cause of death among children aged 1-14 years for 2012 in Spain. Leukemia has the highest incidence, followed by tumors of the central nervous system (CNS) and lymphomas (Hodgkin lymphoma, HL, and Non-Hodgkin's lymphoma, NHL). Spatial distribution of childhood cancer cases has been under concern with the aim of identifying potential risk factors. The two objectives are to study overall spatial clustering and cluster detection of cases of the three main childhood cancer causes, looking to increase etiological knowledge. We ran a case-control study. The cases were children aged 0 to 14 diagnosed with leukemia, lymphomas (HL and NHL) or CNS neoplasm in five Spanish regions for the period 1996-2011. As a control group, we used a sample from the Birth Registry matching every case by year of birth, autonomous region of residence and sex with six controls. We geocoded and validated the address of the cases and controls. For our two objectives we used two different methodologies. For the first, for overall spatial clustering detection, we used the differences of K functions from the spatial point patterns perspective proposed by Diggle and Chetwynd and the second, for cluster detection, we used the spatial scan statistic proposed by Kulldorff with a level for statistical significance of 0.05. We had 1062 cases of leukemia, 714 cases of CNS, 92 of HL and 246 of NHL. Accordingly we had 6 times the number of controls, 6372 controls for leukemia, 4284 controls for CNS, 552 controls for HL and 1476 controls for NHL. We found variations in the estimated empirical D(s) for the different regions and cancers, including some overall spatial clustering for specific regions and distances. We did not find statistically significant clusters. The variations in the estimated empirical D(s) for the different regions and cancers could be partially explained by the differences in the spatial distribution of the population; however, according to the literature

  13. Diet and cataract: a case-control study.

    PubMed

    Theodoropoulou, Sofia; Samoli, Evangelia; Theodossiadis, Panagiotis G; Papathanassiou, Miltiadis; Lagiou, Areti; Lagiou, Pagona; Tzonou, Anastasia

    2014-02-01

    We conducted a case-control study to assess the association between diet and risk of cataract in Athens, Greece. Totals of 314 cases and 314 frequency-matched controls of both sexes, aged 45-85 years and attending the ophthalmology department of a major teaching hospital in Athens, Greece, were included in the study. All participants were interviewed using a semi-quantitative food-frequency questionnaire, covering the average frequency of consumption of about 120 food items. Analyses were conducted through multiple logistic regression. The analysis was carried out taking cataract as a general outcome (all types of cataract combined) and repeated by the specific type of cataract. We found significant inverse associations of cataract with dietary consumption of fish (OR = 0.69, p < 0.001), vegetables (OR = 0.47, p < 0.001), fruits (OR = 0.53, p < 0.001), and potatoes (OR = 0.76, p = 0.004), while consumption of meat was positively associated with cataract (OR = 1.46, p = 0.001). High intake of total fat (OR = 2.00, p < 0.001) and cholesterol (OR = 1.65, p < 0.001) increased the risk of cataract. There was a protective association between cataract risk and intake of carbohydrates (OR = 0.39, p < 0.001), carotene (OR = 0.56, p < 0.001), vitamins C and E (OR = 0.50, p < 0.001 and OR = 0.50, p < 0.001 respectively). We identified an association between the risk of cataract and several food groups and nutrients. Diets rich in fruits, vegetables, fish, pulses and starchy foods may protect against cataract. In addition, high intake of vitamins C and E and carotene with reduction of intake in total fat and cholesterol may be beneficial. Dietary advice along these lines may provide adequate public health guidelines for the delay of age-related cataract.

  14. Association between diabetes and tuberculosis: case-control study.

    PubMed

    Pereira, Susan Martins; Araújo, Gleide Santos de; Santos, Carlos Antônio de Souza Teles; Oliveira, Maeli Gomes de; Barreto, Maurício Lima

    2016-12-22

    To test the association between diabetes and tuberculosis. It is a case-control study, matched by age and sex. We included 323 new cases of tuberculosis with positive results for bacilloscopy. The controls were 323 respiratory symptomatic patients with negative bacilloscopy, from the same health services, such as: ambulatory cases from three referral hospitals and six basic health units responsible for the notifications of new cases of tuberculosis in Salvador, Bahia. Data collection occurred between 2008 and 2010. The instruments used were structured interview, including clinical data, capillary blood glucose (during fasting or postprandial), and the CAGE questionnaire for screening of abusive consumption of alcohol. Descriptive, exploratory, and multivariate analysis was performed using conditional logistic regression. The average age of the cases was 38.5 (SD = 14.2) years and of the controls, 38.5 (SD = 14.3) years. Among cases and controls, most subjects (61%) were male. In univariate analysis we found association between the occurrence of diabetes and tuberculosis (OR = 2.37; 95%CI 1.04-5.42), which remained statistically significant after adjustment for potential confounders (OR = 3.12; 95%CI 1.12-7.94). The association between diabetes and tuberculosis can hinder the control of tuberculosis, contributing to the maintainance of the disease burden. The situation demands increasing early detection of diabetes among people with tuberculosis, in an attempt to improve disease control strategies. Testar a associação entre diabetes e tuberculose. Trata-se de estudo caso-controle, pareado por idade e sexo. Foram incluídos 323 casos novos de tuberculose com resultados positivos à baciloscopia. Os controles foram 323 sintomáticos respiratórios com baciloscopia negativa, oriundos dos mesmos serviços de saúde dos casos: ambulatórios de três hospitais de referência e seis unidades básicas de saúde responsáveis pelas notificações dos casos novos de

  15. 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

  16. Elliptic genera from multi-centers

    NASA Astrophysics Data System (ADS)

    Gaddam, Nava

    2016-05-01

    I show how elliptic genera for various Calabi-Yau threefolds may be understood from supergravity localization using the quantization of the phase space of certain multi-center configurations. I present a simple procedure that allows for the enumeration of all multi-center configurations contributing to the polar sector of the elliptic genera — explicitly verifying this in the cases of the quintic in {P} 4, the sextic in {W}{P} (2,1,1,1,1), the octic in {W}{P} (4,1,1,1,1) and the dectic in {W}{P} (5,2,1,1,1). With an input of the corresponding `single-center' indices (Donaldson-Thomas invariants), the polar terms have been known to determine the elliptic genera completely. I argue that this multi-center approach to the low-lying spectrum of the elliptic genera is a stepping stone towards an understanding of the exact microscopic states that contribute to supersymmetric single center black hole entropy in {N} = 2 supergravity.

  17. Association between aflatoxin B1 occupational airway exposure and risk of hepatocellular carcinoma: a case-control study.

    PubMed

    Lai, Hao; Mo, Xianwei; Yang, Yang; He, Ke; Xiao, Jun; Liu, Chao; Chen, Jiansi; Lin, Yuan

    2014-10-01

    The aim of this study was to determine the airway exposure of sugar and papermaking factory workers to aflatoxin B1 (AFB1) and to explore the potential association between AFB1 airway exposure and the risk of hepatocellular carcinoma (HCC) in a case-control study. Dust samples were collected from the sugarcane bagasse warehouse, and presser and paper production workshops. Blood samples were collected from 181 workshop employees and 203 controls who worked outside the workshop. AFB1 albumin adducts were detected using a double antibody sandwich enzyme-linked immunosorbent assay (ELISA). To explore the association between AFB1 airway exposure and the risk of HCC, the medical records of 68 HCC patients who worked in a sugar and papermaking factory between January 1994 and December 2013 were analyzed. A questionnaire was used to collect information from 150 healthy controls who worked for the same company and lived near the factory. AFB1 was detected in the dust samples, but could not be detected in any of the rice samples. An analysis of serum samples revealed serum AFB1 albumin adducts in 102 (56.35 %) of the study participants. However, in the control group, only 12 (5.9 %) individuals had detectable levels of AFB1 albumin adducts. Those with airway exposure to Aspergillus flavus-contaminated dust had an elevated risk of HCC compared to those without exposure (odds ratio, 5.24; 95 % confidence interval, 2.77-9.88; P = 0.00). The findings of this study indicate that occupational AFB1 airway exposure might be associated with the risk of AFB1-related HCC among the population that was used in this study. Intervention programs aimed at reducing exposure to inhalational AFB1 are needed urgently. Additional suitably designed, multicenter, prospective studies using large samples are needed to further confirm the results.

  18. Risk factors for in-hospital venous thromboembolism in children: a case-control study employing diagnostic validation.

    PubMed

    Branchford, Brian R; Mourani, Peter; Bajaj, Lalit; Manco-Johnson, Marilyn; Wang, Michael; Goldenberg, Neil A

    2012-04-01

    Studies evaluating risk factors for in-hospital venous thromboembolism in children are limited by quality assurance of case definition and/or lack of controlled comparison. The objective of this study is to determine risk factors for the development of in-hospital venous thromboembolism in children. In a case-control study at The Children's Hospital, Colorado, from 1(st) January 2003 to 31(st) December 2009 we employed diagnostic validation methods to determine pediatric in-hospital venous thromboembolism risk factors. Clinical data on putative risk factors were retrospectively collected from medical records of children with International Classification of Diseases, 9th edition codes of venous thromboembolism at discharge, in whom radiological reports confirmed venous thromboembolism and no signs/symptoms of venous thromboembolism were noted on admission. We verified 78 cases of in-hospital venous thromboembolism, yielding an average incidence of 5 per 10,000 hospitalized children per year. Logistical regression analyses revealed that mechanical ventilation, systemic infection, and hospitalization duration of five days or over were statistically significant, independent risk factors for in-hospital venous thromboembolism (OR=3.29, 95%CI=1.53-7.06, P=0.002; OR=3.05, 95%CI=1.57-5.94, P=0.001; and OR=1.03, 95%CI=1.01-1.04, P=0.001, respectively). Using these factors in a risk model, post-test probability of venous thromboembolism was 3.6%. These data indicate that risk of in-hospital venous thromboembolism in children with this risk factor combination may exceed that of hospitalized adults in whom prophylactic anticoagulation is indicated. Substantiation of these findings via multicenter studies could provide the basis for future risk-stratified randomized control trials of pediatric venous thromboembolism prevention.

  19. Incidence and risk factors of aplastic anemia in Latin American countries: the LATIN case-control study

    PubMed Central

    Maluf, Eliane; Hamerschlak, Nelson; Cavalcanti, Alexandre Biasi; Júnior, Álvaro Avezum; Eluf-Neto, José; Falcão, Roberto Passetto; Lorand-Metze, Irene G.; Goldenberg, Daniel; Santana, Cézar Leite; de Oliveira Werneck Rodrigues, Daniela; da Motta Passos, Leny Nascimento; Rosenfeld, Luis Gastão Mange; Pitta, Marimilia; Loggetto, Sandra; Feitosa Ribeiro, Andreza A.; Velloso, Elvira Deolinda; Kondo, Andrea Tiemi; de Miranda Coelho, Erika Oliveira; Pintão, Maria Carolina Tostes; de Souza, Hélio Moraes; Borbolla, José Rafael; Pasquini, Ricardo

    2009-01-01

    Background Associations between aplastic anemia and numerous drugs, pesticides and chemicals have been reported. However, at least 50% of the etiology of aplastic anemia remains unexplained. Design and Methods This was a case-control, multicenter, multinational study, designed to identify risk factors for agranulocytosis and aplastic anemia. The cases were patients with diagnosis of aplastic anemia confirmed through biopsy or bone marrow aspiration, selected through an active search of clinical laboratories, hematology clinics and medical records. The controls did not have either aplastic anemia or chronic diseases. A total of 224 patients with aplastic anemia were included in the study, each case was paired with four controls, according to sex, age group, and hospital where the case was first seen. Information was collected on demographic data, medical history, laboratory tests, medications, and other potential risk factors prior to diagnosis. Results The incidence of aplastic anemia was 1.6 cases per million per year. Higher rates of benzene exposure (≥30 exposures per year) were associated with a greater risk of aplastic anemia (odds ratio, OR: 4.2; 95% confidence interval, CI: 1.82–9.82). Individuals exposed to chloramphenicol in the previous year had an adjusted OR for aplastic anemia of 8.7 (CI: 0.87–87.93) and those exposed to azithromycin had an adjusted OR of 11.02 (CI 1.14–108.02). Conclusions The incidence of aplastic anemia in Latin America countries is low. Although the research study centers had a high coverage of health services, the underreporting of cases of aplastic anemia in selected regions can be discussed. Frequent exposure to benzene-based products increases the risk for aplastic anemia. Few associations with specific drugs were found, and it is likely that some of these were due to chance alone. PMID:19734415

  20. [Pneumonia in the elderly population over 70 years with limited functional condition: case-control study of institutionalized patients].

    PubMed

    Serra Sanchis, B; Martínez Moragón, E; Aguar, M; Fernández Fabrellas, E; Sanz, F; Blanquer, J

    2007-12-01

    Community acquired pneumonia (CAP) of the elderly is an increasingly important growing health problem due to its prevalence and mortality. Among the factors that are usually related with poor evolution are advanced age, poor functional status and coming from a socio-health care institution such as residential homes for the elderly. In this study, we have chosen a population over 70 years of age with limited functional capacity (Barthel Index < 50) in order to know if coming from a residential home for the elderly is an isolated factor that is associated to worse prognosis of CAP. We selected 87 patients over 70 years from a prospective and multicenter study of the hospitalized CAPs during one year. We analyzed the evolution and course of the CAP based on place or origin and then conducted a case-control study of the elderly over 70 years with the Barthel under 50, including 21 elderly from residences and 21 from the own home. In elderly patients over 70 years with CAP, those coming from the residence have a confusional picture more often and come to emergency with lower values of systolic and diastolic blood pressure, lower arterial oxygen saturation, greater involvement on the x-ray, Fine Index is worse and die more often. When we limit the population to those over 70 years with Barthel under 50, we do not find differences in institutionalized patients versus the others. In the elderly over 70 years with CAP, patients from assisted living residences have greater mortality. However, when functional capacity is bad (Barthel < 50), place or origin (community or elderly residence) loses importance and becomes a variable that has no more influence than others in the clinical evolution and course of the CAP.

  1. Outcome of acute upper gastrointestinal bleeding in patients with coronary artery disease: A matched case-control study.

    PubMed

    Thanapirom, Kessarin; Ridtitid, Wiriyaporn; Rerknimitr, Rungsun; Thungsuk, Rattikorn; Noophun, Phadet; Wongjitrat, Chatchawan; Luangjaru, Somchai; Vedkijkul, Padet; Lertkupinit, Comson; Poonsab, Swangphong; Ratanachu-Ek, Thawee; Hansomburana, Piyathida; Pornthisarn, Bubpha; Thongbai, Thirada; Mahachai, Varocha; Treeprasertsuk, Sombat

    2016-01-01

    The risk of upper gastrointestinal bleeding (UGIB) increases in patients with coronary artery disease (CAD) due to the frequent use of antiplatelets. There is some data reporting on treatment outcomes in CAD patients presenting with UGIB. We aim to determine the clinical characteristics and outcomes of UGIB in patients with CAD, compared with non-CAD patients. We conducted a prospective multi-center cohort study (THAI UGIB-2010) that enrolled 981 consecutive hospitalized patients with acute UGIB. A matched case-control analysis using this database, which was collected from 11 tertiary referral hospitals in Thailand between January 2010 and September 2011, was performed. Of 981 hospitalized patients with UGIB, there were 61 CAD patients and 244 gender-matched non-CAD patients (ratio 1:4). UGIB patients with CAD were significantly older, and had more frequently used antiplatelets and warfarin than in non-CAD patients. Compared with non-CAD, the CAD patients had significantly higher Glasgow-Blatchford score, full and pre-endoscopic Rockall score and full. Peptic ulcer in CAD patients was identified more often than in non-CAD patients. UGIB patients with CAD and non-CAD had similar outcomes with regard to mortality rate, re-bleeding, surgery, embolization, and packed erythrocyte transfusion. However, CAD patients had longer duration of hospital stays than non-CAD patients. Two CAD patients died from cardiac arrest after endoscopy, whereas three non-CAD patients died from pneumonia and acute renal failure during their hospitalization. In Thailand, patients presenting with UGIB, concomitant CAD did not affect clinical outcome of treatment, compared with non-CAD patients, except for longer hospital stay.

  2. 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

  3. Risk factors for syphilis in women: case-control study.

    PubMed

    Macêdo, Vilma Costa de; Lira, Pedro Israel Cabral de; Frias, Paulo Germano de; Romaguera, Luciana Maria Delgado; Caires, Silvana de Fátima Ferreira; Ximenes, Ricardo Arraes de Alencar

    2017-08-17

    To determine the sociodemographic, behavioral, and health care factors related to the occurrence of syphilis in women treated at public maternity hospitals. This is a case-control study (239 cases and 322 controls) with women admitted to seven maternity hospitals in the municipality of Recife, Brazil, from July 2013 to July 2014. Eligible women were recruited after the result of the VDRL (Venereal Disease Research Laboratory) under any titration. The selection of cases and controls was based on the result of the serology for syphilis using ELISA (enzyme-linked immunosorbent assay). The independent variables were grouped into: sociodemographic, behavioral, clinical and obstetric history, and health care in prenatal care and maternity hospital. Information was obtained by interview, during hospitalization, with the application of a questionnaire. Odds ratios and 95% confidence intervals were estimated using logistic regression to identify the predicting factors of the variable to be explained. The logistic regression analysis identified as determinant factors for gestational syphilis: education level of incomplete basic education or illiterate (OR = 2.02), lack of access to telephone (OR = 2.4), catholic religion (OR = 1.70 ), four or more pregnancies (OR = 2.2), three or more sexual partners in the last year (OR = 3.1), use of illicit drugs before the age of 18 (OR = 3.0), and use of illicit drugs by the current partner (OR = 1.7). Only one to three prenatal appointments (OR = 3.5) and a previous history of sexually transmitted infection (OR = 9.7) were also identified as determinant factors. Sociodemographic, behavioral, and health care factors are associated with the occurrence of syphilis in women and should be taken into account in the elaboration of universal strategies aimed at the prevention and control of syphilis, but with a focus on situations of greater vulnerability. Determinar os fatores sociodemográficos, comportamentais e de assistência à sa

  4. A Bayesian Approach to Multicenter Trials and Metaanalysis.

    ERIC Educational Resources Information Center

    Berry, Donald A.

    The use of a Bayesian approach in evaluating data from clinical trials with many treatment centers and from many studies is discussed. The main distinction between a metaanalysis and an analysis of a multicenter trial is that different studies may have very different designs, while the centers in a multicenter trial usually follow the same…

  5. Informed conditioning on clinical covariates increases power in case-control association studies.

    PubMed

    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 χ(2) test statistics and a

  6. Multicenter neonatal databases: Trends in research uses.

    PubMed

    Creel, Liza M; Gregory, Sean; McNeal, Catherine J; Beeram, Madhava R; Krauss, David R

    2017-01-13

    In the US, approximately 12.7% of all live births are preterm, 8.2% of live births were low birth weight (LBW), and 1.5% are very low birth weight (VLBW). Although technological advances have improved mortality rates among preterm and LBW infants, improving overall rates of prematurity and LBW remains a national priority. Monitoring short- and long-term outcomes is critical for advancing medical treatment and minimizing morbidities associated with prematurity or LBW; however, studying these infants can be challenging. Several large, multi-center neonatal databases have been developed to improve research and quality improvement of treatments for and outcomes of premature and LBW infants. The purpose of this systematic review was to describe three multi-center neonatal databases. We conducted a literature search using PubMed and Google Scholar over the period 1990 to August 2014. Studies were included in our review if one of the databases was used as a primary source of data or comparison. Included studies were categorized by year of publication; study design employed, and research focus. A total of 343 studies published between 1991 and 2014 were included. Studies of premature and LBW infants using these databases have increased over time, and provide evidence for both neonatology and community-based pediatric practice. Research into treatment and outcomes of premature and LBW infants is expanding, partially due to the availability of large, multicenter databases. The consistency of clinical conditions and neonatal outcomes studied since 1990 demonstrates that there are dedicated research agendas and resources that allow for long-term, and potentially replicable, studies within this population.

  7. Distal scar-to-midline distance in pilonidal Limberg flap surgery is a recurrence-promoting factor: A multicenter, case-control study.

    PubMed

    Kaplan, Mehmet; Ozcan, Onder; Bilgic, Ethem; Kaplan, Elif Tugce; Kaplan, Tugba; Kaplan, Fatma Cigdem

    2017-03-09

    The Limberg flap (LF) procedure is widely performed for the treatment of sacrococcygeal pilonidal sinus (SPS); however, recurrences continues to be observed. The aim of this study was to assess the relationship between LF designs and the risk of SPS recurrence. Sixty-one cases with recurrent disease (study group) and 194 controls, with a minimum of 5 recurrence-free years following surgery (control group), were included in the study. LF reconstructions performed in each group were classified as off-midline closure (OMC) and non-OMC types. Subsequently, the 2 groups were analyzed. After adjustment for all variables, non-OMC types showed the most prominent correlation with recurrence, followed by interrupted suturing type, family history of SPS, smoking, prolonged healing time, and younger age. The best cut-off value for the critical distance from the midline was found to be 11 mm (with 72% sensitivity and 95% specificity for recurrence). We recommend OMC modifications, with the flap tailored to create a safe margin of at least 2 cm between the flap borders and the midline. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Effects of heat and moisture exchangers on tracheal mucociliary clearance in laryngectomized patients: a multi-center case-control study.

    PubMed

    van den Boer, C; Muller, S H; van der Noort, V; Olmos, R A Valdés; Minni, A; Parrilla, C; Hilgers, F J M; van den Brekel, M W M; van der Baan, S

    2015-11-01

    After total laryngectomy, inspired air is no longer optimally conditioned by the upper airways. Impaired mucociliary clearance and histological changes of respiratory epithelium, such as loss of ciliated cells, have been described in laryngectomized patients. Heat and moisture exchangers (HMEs) are passive humidifiers that re-condition the inspired air. Aim of this study was to assess the effect of HMEs on tracheal epithelium and tracheal mucus transport velocity (TMV). Tracheal brush biopsies were collected in three groups of TLE patients: 21 long-term HME users, 10 non-HME users, and 16 non-HME users before and after 4-9 months HME use. Tracheal epithelium biopsies were assessed using a digital high-speed camera mounted onto a light microscope. TMV was determined by scintigraphy in the first two patient groups. Significantly more ciliated cells were found in HME users compared to non-HME users (p = 0.05). TMV was higher in HME users (median 2 mm/min; 0-7.9) compared to non-HME users (median 0.8 mm/min; 0-12.3), but this difference was not significant (p = 0.37). One-hour breathing without HME in long-term HME users did not measurably decrease TMV (p = 0.13). The long-term use of an HME restores/prevents the loss of tracheal ciliated cells. A significant improvement in TMV was not found. Short-term (one hour) detachment of an HME has no measurable effect on TMV.

  9. Hair dye use, regular exercise, and the risk and prognosis of prostate cancer: multicenter case-control and case-only studies.

    PubMed

    Tai, Shu-Yu; Hsieh, Hui-Min; Huang, Shu-Pin; Wu, Ming-Tsang

    2016-03-21

    This study investigated the effects that hair dye use and regular exercise exert on the risk and prognosis of prostate cancer. We studied 296 cases of histologically confirmed prostate cancer and 296 age- (in 2-y bands), ethnicity-, and hospital-matched controls in Taiwan between August 2000 and December 2008. To determine the rate of prostate cancer survival, another 608 incident prostate cancer cases occurring between August 2000 and December 2007 were investigated. Information on hair dye use and regular exercise was obtained using a standardized questionnaire. The use of hair dyes was associated with a significant 2.15-fold odds of developing prostate cancer (adjusted odds ratio = 2.15, 95% confidence interval [CI] = 1.32-3.57), but was not associated with prostate cancer survival, compared with no use. The significant risks were more prominent in users aged < 60 years who had used hair dyes for > 10 years, > 6 times per year, and started using hair dyes before 1980. By contrast, regular exercise significantly reduced the number of prostate-cancer-specific death (adjusted hazard ratio = 0.37, 95% CI = 0.16-0.83); the protective effect of exercise was more prominent among cancer patients who exercised daily (≥ 7 times/week). However, exercise could not prevent the development of prostate cancer. Hair dye use increased the risk of prostate cancer, whereas regular exercise reduced the number of prostate-cancer-specific deaths.

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

    PubMed

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

    2017-08-01

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

  11. A multicenter case-control study on screening of single nucleotide polymorphisms in estrogen-metabolizing enzymes and susceptibility to uterine leiomyoma in han chinese.

    PubMed

    Shen, Yang; Ren, Mu-Lan; Xu, Jie; Xu, Qian; Ding, Yi-Qian; Wu, Zhi-Cong; Zhang, Hai-Bao; Huang, Xian-Xia; Cai, Yun-Lang

    2014-01-01

    Uterine leiomyoma (UL) is an estrogen-responsive benign tumor in the female reproductive system and the main risk of hysterectomy for women. However, gene polymorphism of estrogen-metabolizing enzymes may lead to the different susceptibility to UL. We detected 10 single mucleotide polymorphisms in three key estrogen metabolite enzymes (COMT, CYP1A1, CYP1B1) in a Chinese Han population consisting of 800 patients and 800 healthy women from five different medical centers. The genetic polymorphism of rs3087869 (IVS1+2329C>T) (OR 3.200, 95% CI 1.614-6.345) and rs4680 (Val158Met) (OR 5.675, 95% CI 2.696-11.942) loci on COMT, rs1048943 (Ile462Val) (OR 4.629, 95% CI 2.216-9.672) and rs4646422 (Gly45Asp) (OR 3.240, 95% CI 1.624-6.461) loci on CYP1A1 and rs1065827 (Ala119Ser) (OR 5.635, 95% CI 2.990-10.619) locus on CYP1B1 were the risk factors to UL development and rs1056836 (Leu432Val) (OR 0.188, 95% CI 0.061-0.575) locus on CYB1B1 may be the protective factor to UL. The results provide a theoretical basis for genetic screening and early intervention to UL-susceptible populations.

  12. Improved survival among ICU-hospitalized patients with community-acquired pneumonia by unidentified organisms: a multicenter case-control study.

    PubMed

    Rello, J; Diaz, E; Mañez, R; Sole-Violan, J; Valles, J; Vidaur, L; Zaragoza, R; Gattarello, S

    2017-01-01

    A retrospective analysis from prospectively collected data was conducted in intensive care units (ICUs) at 33 hospitals in Europe comparing the trend in ICU survival among adults with severe community-acquired pneumonia (CAP) due to unknown organisms from 2000 to 2015. The secondary objective was to establish whether changes in antibiotic policies were associated with different outcomes. ICU mortality decreased (p = 0.02) from 26.9 % in the first study period (2000-2002) to 15.7 % in the second period (2008-2015). Demographic data and clinical severity at admission were comparable between groups, except for age over 65 years and incidence of cardiomyopathy. Over time, patients received higher rates of combination therapy (94.3 vs. 77.2 %; p < 0.01) and early (<3 h) antibiotic delivery (72.9 vs. 50.3 %; p < 0.01); likewise, the 2008-2015 group was more likely to receive adequate antibiotic prescription [as defined by the Infectious Diseases Society of America/American Thoracic Society (IDSA/ATS) guidelines] than the 2000-2002 group (70.7 vs. 48.2 %; p < 0.01). Multivariate analysis showed an independent association between decreased ICU mortality and early (<3 h) antibiotic administration [odds ratio (OR) 3.48 [1.70-7.15], p < 0.01] or adequate antibiotic prescription according to guidelines (OR 2.22 [1.11-4.43], p = 0.02). In conclusion, our findings suggest that ICU mortality in severe CAP due to unidentified organisms has decreased in the last 15 years. Several changes in management and better compliance with guidelines over time were associated with increased survival.

  13. Clinicopathological features of patients with malignant mesothelioma in a multicenter, case-control study: no role for ABO-Rh blood groups.

    PubMed

    Utkan, Güngör; Ürün, Yüksel; Cangir, Ayten Kayi; Kılıç, Dalokay; Özdemir, Nuriye Yildirim; Oztuna, Derya Gokmen; Bulut, Erhan; Arslan, Ülkü Yalçintaş; Koçer, Murat; Kavukçu, Şevket; İçli, Fikri

    2013-01-01

    Malignant mesothelioma (MM) is an aggressive tumor of mesothelial surfaces. Previous studies have observed an association between ABO blood groups and risk of certain malignancies, including pancreatic and gastric cancer; however, no information on any association with MM risk is available. The aim of this study was to investigate possible associations amoong MM clinicopathological features and ABO blood groups and Rh factor. In 252 patients with MM, the ABO blood group and Rh factor were examined and compared with the control group of 3,022,883 healthy volunteer blood donors of Turkish Red Crescent between 2004 and 2011. The relationship of blood groups with various clinicopathological features were also evaluated in the patient group. The median age was 55 (range: 27-86) and 61.5% of patients were male. While 82.8% of patients had a history of exposure to asbestos, 60.7% of patients had a smoking history. Epithelioid (65.1%) was the most common histology and 18.7% of patients had mixed histology. Overall, the ABO blood group distribution of the 252 patients with MM was comparable with the general population. The median overall survival (OS) was 14 months (95% confidence interval, 11.3-16.6 months). The median OS for A, B, AB, and O were 11, 15, 16, and 15 months respectively (p=0.396). First line chemotherapy was administered to 118 patients. The median OS of patients on pemetrexed or gemcitabine was longer than patient who was not administered chemotherapy [17 months (95%CI, 11.7-22.2) vs. 9 months (95%CI, 6.9-11.0); p<0.001]. The results of this study suggest that patients with MM can benefit from treatment with pemetrexed or gemcitabine in combination with cisplatin. We did not observe a statistically significant association between ABO blood group and risk of MM.

  14. Carcinogen metabolism in human lung tissues and the effect of tobacco smoking: results from a case--control multicenter study on lung cancer patients.

    PubMed Central

    Bartsch, H; Petruzzelli, S; De Flora, S; Hietanen, E; Camus, A M; Castegnaro, M; Alexandrov, K; Rojas, M; Saracci, R; Giuntini, C

    1992-01-01

    Cigarette smoking is the strongest risk factor for lung cancer, but genetically determined variations in the activities of pulmonary enzyme that metabolize tobacco-derived carcinogens may affect individual risk. To investigate whether these enzymes (e.g., CYP1A-related) can serve as markers for carcinogen-DNA damage, lung tissue specimens were taken during surgery from middle-aged men with either lung cancer or non-neoplastic lung disease. Phase I [aryl hydrocarbon hydroxylase (AHH), ethoxycoumarin O-deethylase (ECOD)] and phase II (epoxide hydrolase, UDP-glucuronosyltransferase, glutathione S-transferase) enzyme activities, glutathione and malondialdehyde contents were determined in lung parenchyma and/or bronchial tissues; some samples were also analyzed for DNA adducts, using 32P-postlabeling. The data were then analyzed for the following: a) differences in metabolic profiles between bronchial and parenchymal lung tissue; b) the effect of recent exposure to tobacco smoke on enzyme inducibility and benzo[a]pyrene metabolism; c) differences in enzyme inducibility between lung cancer and non-lung cancer patients; d) the effect of smoking on metabolism of mutagens in vitro; e) pulmonary DNA adduct levels and AHH activity in lung parenchyma of smokers and ex-smokers; f) lipid peroxidation products in lung tissue from lung cancer and non-lung cancer patients, as related to smoking habits and degree of airway obstruction; and g) prognostic value of AHH pulmonary activity in lung cancer patients. The results demonstrate a pronounced effect of tobacco smoke on pulmonary metabolism of xenobiotics and prooxidant state and suggest the existence of a metabolic phenotype at higher risk for tobacco-associated lung cancer. PMID:1336722

  15. 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

  16. Mixed model with correction for case-control ascertainment increases association power.

    PubMed

    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

    2015-05-07

    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 χ(2) 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 χ(2) 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.

  17. Management of Pneumothorax in Emergency Medicine Departments: Multicenter Trial

    PubMed Central

    Ince, Abdulkadir; Ozucelik, Dogac Niyazi; Avci, Akkan; Nizam, Ozgur; Dogan, Halil; Topal, Mehmet Ali

    2013-01-01

    Background: Pneumothorax is common and life-threatening clinical condition which may require emergency treatment in Emergency Medicine Departments. Objectives: We aimed to reveal the epidemiological analysis of the patients admitted to the Emergency Department with pneumothorax. Material and Methods: This case-control and multi-center study was conducted in the patients treated with the diagnosis of pneumothorax between 01.01.2010-31.12.2010. Patient data were collected from hospital automation system. According to the etiology of the pneumothorax, study groups were arranged like spontaneous pneumothorax and traumatic pneumothorax. Results: 82.2% (n = 106) of patients were male and 17.8% (n = 23) of patients were female and mean age were 31.3 ± 20,2 (Minimum: 1, Maximum: 87). 68.2% (n = 88) of patients were spontaneous pneumothorax (61.36%, n=79 were primary spontaneous pneumothorax) and 31.8% (n = 41) of patients were traumatic pneumothorax (21.95% were iatrogenic pneumothorax). Main complaint is shortness of breath (52.3%, n=67) and 38% (n=49) of patients were smokers. Posteroanterior (PA) Chest X-Ray has been enough for 64.3% (n = 83) of the patients' diagnosis. Tube thoracostomy is applied to 84.5% (n = 109) of patients and surgery is applied to 9.3% (n = 12) of patients and 6.2% (n = 8) of patients were discharged with conservative treatment. Spontaneous pneumothorax showed statistically significant high recurrence compared with traumatic pneumothorax (P = 0.007). 4.65% of (n = 6) patients died. The average age of those who died (9.3 ± 19.9), statistically were significantly lower the mean age of living patients (32.4 ± 19.7) (t test, P = 0,006). 83.33% of the patients who died were neonatals and in the 0-1 years age group, and five of these patients were secondary spontaneous pneumothorax, and one of these patients were iatrogenic pneumothorax due to mechanical ventilation. Conclusions: Pneumothorax in adults can be treated by tube thoracostomy or

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

    PubMed

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

    2015-11-27

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

  19. AURORA: bariatric surgery registration in women of reproductive age - a multicenter prospective cohort study.

    PubMed

    Jans, Goele; Matthys, Christophe; Bel, Sarah; Ameye, Lieveke; Lannoo, Matthias; Van der Schueren, Bart; Dillemans, Bruno; Lemmens, Luc; Saey, Jean-Pierre; van Nieuwenhove, Yves; Grandjean, Pascale; De Becker, Ben; Logghe, Hilde; Coppens, Marc; Roelens, Kristien; Loccufier, Anne; Verhaeghe, Johan; Devlieger, Roland

    2016-07-29

    The expansion of the obesity epidemic is accompanied with an increase in bariatric procedures, in particular in women of reproductive age. The weight loss induced by the surgery is believed to reverse the negative impact of overweight and obesity on female reproduction, however, research is limited to in particular retrospective cohort studies and a growing number of small case-series and case-(control) studies. AURORA is a multicenter prospective cohort study. The main objective is to collect long-term data on reproductive outcomes before and after bariatric surgery and in a subsequent pregnancy. Women aged 18-45 years are invited to participate at 4 possible inclusion moments: 1) before surgery, 2) after surgery, 3) before 15 weeks of pregnancy and 4) in the immediate postpartum period (day 3-4). Depending on the time of inclusion, data are collected before surgery (T1), 3 weeks and 3, 6, 12 or x months after surgery (T2-T5) and during the first, second and third trimester of pregnancy (T6-T8), at delivery (T9) and 6 weeks and 6 months after delivery (T10-T11). Online questionnaires are send on the different measuring moments. Data are collected on contraception, menstrual cycle, sexuality, intention of becoming pregnant, diet, physical activity, lifestyle, psycho-social characteristics and dietary supplement intake. Fasting blood samples determine levels of vitamin A, D, E, K, B-1, B-12 and folate, albumin, total protein, coagulation parameters, magnesium, calcium, zinc and glucose. Participants are weighted every measuring moment. Fetal ultrasounds and pregnancy course and complications are reported every trimester of pregnancy. Breastfeeding is recorded and breast milk composition in the postpartum period is studied. AURORA is a multicenter prospective cohort study extensively monitoring women before undergoing bariatric surgery until a subsequent pregnancy and postpartum period. Retrospectively registered (July 2015 - NCT02515214 ).

  20. A New Comparison of Nested Case-Control and Case-Cohort Designs and Methods

    PubMed Central

    Kim, Ryung S.

    2014-01-01

    Existing literature comparing statistical properties of nested case-control and case-cohort methods have become insufficient for present day epidemiologists. The literature has not reconciled conflicting conclusions about the standard methods. Moreover, a comparison including newly developed methods, such as inverse probability weighting methods, is needed. Two analytical methods for nested case-control studies and six methods for case-cohort studies using proportional hazards regression model were summarized and their statistical properties were compared. The answer to which design and method is more powerful was more nuanced than what was previously reported. For both nested case-control and case-cohort designs, inverse probability weighting methods were more powerful than the standard methods. However, the difference became negligible when the proportion of failure events was very low (<1%) in the full cohort. The comparison between two designs depended on the censoring types and incidence proportion: with random censoring, nested case-control designs coupled with the inverse probability weighting method yielded the highest statistical power among all methods for both designs. With fixed censoring times, there was little difference in efficiency between two designs when inverse probability weighting methods were used; however, the standard case-cohort methods were more powerful than the conditional logistic method for nested case-control designs. As the proportion of failure events in the full cohort became smaller (<10%), nested case-control methods outperformed all case-cohort methods and the choice of analytic methods within each design became less important. When the predictor of interest was binary, the standard case-cohort methods were often more powerful than the conditional logistic method for nested case-control designs. PMID:25446306

  1. Case-control vaccine effectiveness studies: Data collection, analysis and reporting results.

    PubMed

    Verani, Jennifer R; Baqui, Abdullah H; Broome, Claire V; Cherian, Thomas; Cohen, Cheryl; Farrar, Jennifer L; Feikin, Daniel R; Groome, Michelle J; Hajjeh, Rana A; Johnson, Hope L; Madhi, Shabir A; Mulholland, Kim; O'Brien, Katherine L; Parashar, Umesh D; Patel, Manish M; Rodrigues, Laura C; Santosham, Mathuram; Scott, J Anthony; Smith, Peter G; Sommerfelt, Halvor; Tate, Jacqueline E; Victor, J Chris; Whitney, Cynthia G; Zaidi, Anita K; Zell, Elizabeth R

    2017-06-05

    The case-control methodology is frequently used to evaluate vaccine effectiveness post-licensure. The results of such studies provide important insight into the level of protection afforded by vaccines in a 'real world' context, and are commonly used to guide vaccine policy decisions. However, the potential for bias and confounding are important limitations to this method, and the results of a poorly conducted or incorrectly interpreted case-control study can mislead policies. In 2012, a group of experts met to review recent experience with case-control studies evaluating vaccine effectiveness; we summarize the recommendations of that group regarding best practices for data collection, analysis, and presentation of the results of case-control vaccine effectiveness studies. Vaccination status is the primary exposure of interest, but can be challenging to assess accurately and with minimal bias. Investigators should understand factors associated with vaccination as well as the availability of documented vaccination status in the study context; case-control studies may not be a valid method for evaluating vaccine effectiveness in settings where many children lack a documented immunization history. To avoid bias, it is essential to use the same methods and effort gathering vaccination data from cases and controls. Variables that may confound the association between illness and vaccination are also important to capture as completely as possible, and where relevant, adjust for in the analysis according to the analytic plan. In presenting results from case-control vaccine effectiveness studies, investigators should describe enrollment among eligible cases and controls as well as the proportion with no documented vaccine history. Emphasis should be placed on confidence intervals, rather than point estimates, of vaccine effectiveness. Case-control studies are a useful approach for evaluating vaccine effectiveness; however careful attention must be paid to the collection

  2. Evaluating risk factors for protein-energy malnutrition in children under the age of six years: a case-control study from Iran.

    PubMed

    Sharghi, Afshan; Kamran, Aziz; Faridan, Mohammad

    2011-01-01

    Protein-energy malnutrition is one of the most important public health problems in Iran. It not only accounts for more than half of child mortality but can also produce somatic and mental impairment in survivors. The main aim of this study was to identify risk factors for protein-energy malnutrition in children under 6 years of age in Namin city. This was a population-based, multicenter case-control study. Seventy-six children with malnutrition and 76 children without malnutrition were randomly recruited for case and control groups. The prevalence of risk factors in the two groups was compared. Data were gathered from a health center database and interviews with mothers and health workers. The Wilcoxon signed-rank test and logistic regression were used for data analysis. Female gender, poverty, short maternal height, and use of unhygienic latrines in the home were significantly associated with childhood malnutrition (P < 0.05). The results of this study indicate four main factors (poverty, small maternal height, female gender, and absence of hygienic latrines in the home) as underlying factors in malnutrition of children under the age of 6 years.

  3. Evaluating risk factors for protein-energy malnutrition in children under the age of six years: a case-control study from Iran

    PubMed Central

    Sharghi, Afshan; Kamran, Aziz; Faridan, Mohammad

    2011-01-01

    Introduction: Protein-energy malnutrition is one of the most important public health problems in Iran. It not only accounts for more than half of child mortality but can also produce somatic and mental impairment in survivors. The main aim of this study was to identify risk factors for protein-energy malnutrition in children under 6 years of age in Namin city. Methods: This was a population-based, multicenter case-control study. Seventy-six children with malnutrition and 76 children without malnutrition were randomly recruited for case and control groups. The prevalence of risk factors in the two groups was compared. Data were gathered from a health center database and interviews with mothers and health workers. The Wilcoxon signed-rank test and logistic regression were used for data analysis. Results: Female gender, poverty, short maternal height, and use of unhygienic latrines in the home were significantly associated with childhood malnutrition (P < 0.05). Conclusion: The results of this study indicate four main factors (poverty, small maternal height, female gender, and absence of hygienic latrines in the home) as underlying factors in malnutrition of children under the age of 6 years. PMID:21887115

  4. 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

    2015-04-07

    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.

  5. [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.

  6. 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

  7. 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

  8. 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

  9. Multicenter Epidemiological Studies of Atherosclerosis Imaging

    PubMed Central

    Liu, Songtao; Bluemke, David A.

    2011-01-01

    Cardiovascular disease is the leading course of death and disability. Conventional cardiac risk factors do not fully explain the level of cardiovascular risk, incidence of coronary artery disease, and coronary events. Risk stratification and therapy based solely on these conventional risk factors may overlook a population who would benefit from lifestyle and risk factor modification. Thus, research has recently focused on improving risk assessment with new tools in an effort to better identify subjects at highest risk and in need of aggressive management. Cardiovascular imaging, both in coronary and extracoronary arterial beds, has proven to be very helpful in this regard. In this article, we review the current literature from multicenter epidemiology studies on the utility of noninvasive imaging modalities for risk stratification in the context of conventional risk factor evaluation. PMID:20805734

  10. A premarketing multicenter trial of lorazepam injection.

    PubMed

    Philbrook, F A; Hatt, D L

    1983-01-01

    Before the introduction of lorazepam injection to the Canadian market, its usefulness and acceptability were assessed in an open multicenter study. Anesthesiologists in teaching hospitals across the country were asked to substitute lorazepam injection for their usual anxiolytic premedicant in ten patients and to complete a brief case report on each patient. The results from 360 patients showed that suitable preoperative sedation, accompanied by anxiolysis but without undue effects on arousability, was obtained in 88% of the patients prior to surgery. The adverse effect most often reported, accounting for 84% of the drug-related adverse reactions, was postoperative drowsiness, which highlighted the need to administer the drug at least two hours before surgery. The anesthesiologists found lorazepam injection to be a satisfactory premedicant, rating it excellent to good in 73% of the patients treated.

  11. 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

  12. A general regression framework for a secondary outcome in case-control studies.

    PubMed

    Tchetgen Tchetgen, Eric J

    2014-01-01

    Modern case-control studies typically involve the collection of data on a large number of outcomes, often at considerable logistical and monetary expense. These data are of potentially great value to subsequent researchers, who, although not necessarily concerned with the disease that defined the case series in the original study, may want to use the available information for a regression analysis involving a secondary outcome. Because cases and controls are selected with unequal probability, regression analysis involving a secondary outcome generally must acknowledge the sampling design. In this paper, the author presents a new framework for the analysis of secondary outcomes in case-control studies. The approach is based on a careful re-parameterization of the conditional model for the secondary outcome given the case-control outcome and regression covariates, in terms of (a) the population regression of interest of the secondary outcome given covariates and (b) the population regression of the case-control outcome on covariates. The error distribution for the secondary outcome given covariates and case-control status is otherwise unrestricted. For a continuous outcome, the approach sometimes reduces to extending model (a) by including a residual of (b) as a covariate. However, the framework is general in the sense that models (a) and (b) can take any functional form, and the methodology allows for an identity, log or logit link function for model (a).

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

    PubMed

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

    2015-02-10

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

  14. Mixed Model Association with Family-Biased Case-Control Ascertainment.

    PubMed

    Hayeck, Tristan J; Loh, Po-Ru; Pollack, Samuela; Gusev, Alexander; Patterson, Nick; Zaitlen, Noah A; Price, Alkes L

    2017-01-05

    Mixed models have become the tool of choice for genetic association studies; however, standard mixed model methods may be poorly calibrated or underpowered under family sampling bias and/or case-control ascertainment. Previously, we introduced a liability threshold-based mixed model association statistic (LTMLM) to address case-control ascertainment in unrelated samples. Here, we consider family-biased case-control ascertainment, where case and control subjects are ascertained non-randomly with respect to family relatedness. Previous work has shown that this type of ascertainment can severely bias heritability estimates; we show here that it also impacts mixed model association statistics. We introduce a family-based association statistic (LT-Fam) that is robust to this problem. Similar to LTMLM, LT-Fam is computed from posterior mean liabilities (PML) under a liability threshold model; however, LT-Fam uses published narrow-sense heritability estimates to avoid the problem of biased heritability estimation, enabling correct calibration. In simulations with family-biased case-control ascertainment, LT-Fam was correctly calibrated (average χ(2) = 1.00-1.02 for null SNPs), whereas the Armitage trend test (ATT), standard mixed model association (MLM), and case-control retrospective association test (CARAT) were mis-calibrated (e.g., average χ(2) = 0.50-1.22 for MLM, 0.89-2.65 for CARAT). LT-Fam also attained higher power than other methods in some settings. In 1,259 type 2 diabetes-affected case subjects and 5,765 control subjects from the CARe cohort, downsampled to induce family-biased ascertainment, LT-Fam was correctly calibrated whereas ATT, MLM, and CARAT were again mis-calibrated. Our results highlight the importance of modeling family sampling bias in case-control datasets with related samples. Copyright © 2017 American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

  15. General practitioner notes as a source of information for case-control studies in young women. UK National Case-Control Study Group.

    PubMed Central

    Chilvers, C E; Pike, M C; Taylor, C N; Hermon, C; Crossley, B; Smith, S J

    1994-01-01

    STUDY OBJECTIVE--The UK National Case-Control Study was carried out to investigate the relationship between oral contraceptive use and breast cancer risk. This study investigates whether general practitioner notes could be used as the sole data source for epidemiological studies of young women and what the effect would be on non-response and recall bias. DESIGN--Case-control study with data on gynaecological, obstetric, and contraceptive history collected at interview and from general practitioners' notes. Information from these two sources was compared. SETTING--This was a population-based study. PARTICIPANTS--Altogether 755 women with breast cancer aged under 36 years at diagnosis, each with an age-matched control, participated in the study. Response rates at interview were 72% and 89% for cases and controls but GP data were available for 90% of the 1049 case and first-selected control pairs. MAIN RESULTS--There was generally good agreement between the two data sources with respect to obstetric history and gynaecological procedures (hysterectomy, oophorectomy, and tubal ligation). The use of intra-uterine devices, or diaphragm, and partner's vasectomy were not reliably recorded in the GP's notes. The overall results of the UK study would have been qualitatively the same with respect to the relationship between oral contraceptive use and breast cancer risk if GP notes only had been used, in spite of the fact that only about half of all oral contraceptive usage was recorded in the notes. Response rates would have been higher, recall bias eliminated, and the cost of the study halved. CONCLUSIONS--When planning case-control studies in young women, the possibility of using GP notes as the primary data source should be considered. Lack of data on potential confounding factors is a possible drawback to such use. The practice of destroying GP's notes shortly after the death of patients seriously restricts the possibility of using these notes when studying rapidly fatal

  16. 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.

  17. 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…

  18. 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…

  19. 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…

  20. Family-Based versus Unrelated Case-Control Designs for Genetic Associations

    PubMed Central

    Evangelou, Evangelos; Trikalinos, Thomas A; Salanti, Georgia; Ioannidis, John P. A

    2006-01-01

    The most simple and commonly used approach for genetic associations is the case-control study design of unrelated people. This design is susceptible to population stratification. This problem is obviated in family-based studies, but it is usually difficult to accumulate large enough samples of well-characterized families. We addressed empirically whether the two designs give similar estimates of association in 93 investigations where both unrelated case-control and family-based designs had been employed. Estimated odds ratios differed beyond chance between the two designs in only four instances (4%). The summary relative odds ratio (ROR) (the ratio of odds ratios obtained from unrelated case-control and family-based studies) was close to unity (0.96 [95% confidence interval, 0.91–1.01]). There was no heterogeneity in the ROR across studies (amount of heterogeneity beyond chance I2 = 0%). Differences on whether results were nominally statistically significant (p < 0.05) or not with the two designs were common (opposite classification rates 14% and 17%); this reflected largely differences in power. Conclusions were largely similar in diverse subgroup analyses. Unrelated case-control and family-based designs give overall similar estimates of association. We cannot rule out rare large biases or common small biases. PMID:16895437

  1. 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...

  2. Analysis of secondary outcomes in nested case-control study designs.

    PubMed

    Kim, Ryung S; Kaplan, Robert C

    2014-10-30

    One of the main perceived advantages of using a case-cohort design compared with 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 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 with that of the case-cohort design when the primary and secondary outcomes were positively correlated. The proposed method is illustrated with the data from a cohort in Cardiovascular Health Study to study the association of C-reactive protein levels and the incidence of congestive heart failure.

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

    USDA-ARS?s Scientific Manuscript database

    There are conflicting reports concerning the association of T. gondii infection and schizophrenia. Therefore, we determined such association in a Mexican population of Mestizo ethnicity. Through a case-control study design, 50 schizophrenic patients and 150 control subjects matched by gender, age, r...

  4. The potential of the case-control method for rapid epidemiological assessment.

    PubMed

    Baltazar, J C

    1991-01-01

    Over the past few decades, the case-control method has been mostly applied to risk-factor studies of chronic diseases. Recently, among its new applications is the use of the method to study the health effect of improvements in sanitation and water supply. The methodological considerations, prospects and constraints of the method for rapid assessment are reviewed.

  5. 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…

  6. A Case Control Study of Suicide and Attempted Suicide in Older Adults.

    ERIC Educational Resources Information Center

    Beautrais, Annette L.

    2002-01-01

    Risk factors for serious suicidal behavior among older adults were examined in a case control study of adults aged 55 and older who died by suicide or made suicide attempts and who were compared with randomly selected comparison subjects. Multivariate analyses suggested that mood disorders were the most significant risk factor for suicidal…

  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. 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…

  9. 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…

  10. How to quantify information loss due to phase ambiguity in haplotype case-control studies.

    PubMed

    Uh, Hae-Won; Houwing-Duistermaat, Jeanine J; Putter, Hein; van Houwelingen, Hans C

    2005-12-30

    Assigning haplotypes in a case-control study is a challenging problem. We proposed a method to quantify the information loss due to missing phase information. We determined which individuals were responsible for the information loss, and calculated how much information could be gained when the ambiguous individuals could be resolved by adding additional parental information.

  11. 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…

  12. 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…

  13. 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…

  14. 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...

  15. Alcohol consumption and psoriatic risk: a meta-analysis of case-control studies.

    PubMed

    Zhu, Kun-Ju; Zhu, Cheng-Yao; Fan, Yi-Ming

    2012-09-01

    Psoriasis is one of the most common dermatological disorders. The association between alcohol consumption and psoriasis has been inconsistent among studies. To examine the magnitude of the risk of developing psoriasis for drinking populations compared to those with non-drinking, and to determine causes of the variation in odds ratios (OR) between various case-control studies, we performed a comprehensive published work search and a meta-analysis of case-control studies considering prevalence. We did electronic searches on Medline, and searched reports to identify case-control studies of prevalent of psoriasis. We did meta-analyses of study-specific incremental estimates to determine the risk of psoriasis associated with drinking. The magnitude of the OR was analyzed by combining 15 case-control studies that matched defined criteria. The variance in OR between studies was explored. The overall OR of psoriasis for drinking persons compared to those with non-drinking was 1.531 (95% confidence interval [CI] = 1.164-2.014, P = 0.002) and the association remains statistically significant across a number of stratified analyses in European descent subgroup (OR = 1.432, 95% CI = 1.085-1.889, P = 0.011) and also persists in sensitivity analyses performed to assess the potential effect of varying psoriasis outcome definitions. Alcohol consumption is associated with increased risk of psoriasis. These epidemiological observations should inform the exploration of biological mechanisms that link alcohol consumption with psoriasis.

  16. A Case Control Study of Suicide and Attempted Suicide in Older Adults.

    ERIC Educational Resources Information Center

    Beautrais, Annette L.

    2002-01-01

    Risk factors for serious suicidal behavior among older adults were examined in a case control study of adults aged 55 and older who died by suicide or made suicide attempts and who were compared with randomly selected comparison subjects. Multivariate analyses suggested that mood disorders were the most significant risk factor for suicidal…

  17. 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.

  18. Uncovering selection bias in case-control studies using Bayesian post-stratification.

    PubMed

    Geneletti, S; Best, N; Toledano, M B; Elliott, P; Richardson, S

    2013-07-10

    Case-control studies are particularly prone to selection bias, which can affect odds ratio estimation. Approaches to discovering and adjusting for selection bias have been proposed in the literature using graphical and heuristic tools as well as more complex statistical methods. The approach we propose is based on a survey-weighting method termed Bayesian post-stratification and follows from the conditional independences that characterise selection bias. We use our approach to perform a selection bias sensitivity analysis by using ancillary data sources that describe the target case-control population to re-weight the odds ratio estimates obtained from the study. The method is applied to two case-control studies, the first investigating the association between exposure to electromagnetic fields and acute lymphoblastic leukaemia in children and the second investigating the association between maternal occupational exposure to hairspray and a congenital anomaly in male babies called hypospadias. In both case-control studies, our method showed that the odds ratios were only moderately sensitive to selection bias.

  19. 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…

  20. 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…

  1. A multicenter study to map genes for Fuchs endothelial corneal dystrophy: baseline characteristics and heritability.

    PubMed

    Louttit, Megan D; Kopplin, Laura J; Igo, Robert P; Fondran, Jeremy R; Tagliaferri, Angela; Bardenstein, David; Aldave, Anthony J; Croasdale, Christopher R; Price, Marianne O; Rosenwasser, George O; Lass, Jonathan H; Iyengar, Sudha K

    2012-01-01

    To describe the methods for family and case-control recruitment for a multicenter genetic and associated heritability analyses of Fuchs endothelial corneal dystrophy (FECD). Twenty-nine enrolling sites with 62 trained investigators and coordinators gathered individual and family information, graded the phenotype, and collected blood and/or saliva for genetic analysis on all individuals with and without FECD. The degree of FECD was assessed in a 0 to 6 semiquantitative scale using standardized clinical methods with pathological verification of FECD on at least 1 member of each family. Central corneal thickness was measured by ultrasonic pachymetry. Three hundred twenty-two families with 330 affected sibling pairs with FECD were enrolled and included a total of 650 sibling pairs of all disease grades. Using the entire 7-step FECD grading scale or a dichotomous definition of severe disease, heritability was assessed in families via sib-sib correlations. Both binary indicators of severe disease and semiquantitative measures of disease severity were significantly heritable, with heritability estimates of 30% for severe disease, 37% to 39% for FECD score, and 47% for central corneal thickness. Genetic risk factors have a strong role in the severity of the FECD phenotype and corneal thickness. Genotyping this cohort with high-density genetic markers followed by appropriate statistical analyses should lead to novel loci for disease susceptibility.

  2. Case-control analysis in highway safety: Accounting for sites with multiple crashes.

    PubMed

    Gross, Frank

    2013-12-01

    There is an increased interest in the use of epidemiological methods in highway safety analysis. The case-control and cohort methods are commonly used in the epidemiological field to identify risk factors and quantify the risk or odds of disease given certain characteristics and factors related to an individual. This same concept can be applied to highway safety where the entity of interest is a roadway segment or intersection (rather than a person) and the risk factors of interest are the operational and geometric characteristics of a given roadway. One criticism of the use of these methods in highway safety is that they have not accounted for the difference between sites with single and multiple crashes. In the medical field, a disease either occurs or it does not; multiple occurrences are generally not an issue. In the highway safety field, it is necessary to evaluate the safety of a given site while accounting for multiple crashes. Otherwise, the analysis may underestimate the safety effects of a given factor. This paper explores the use of the case-control method in highway safety and two variations to account for sites with multiple crashes. Specifically, the paper presents two alternative methods for defining cases in a case-control study and compares the results in a case study. The first alternative defines a separate case for each crash in a given study period, thereby increasing the weight of the associated roadway characteristics in the analysis. The second alternative defines entire crash categories as cases (sites with one crash, sites with two crashes, etc.) and analyzes each group separately in comparison to sites with no crashes. The results are also compared to a "typical" case-control application, where the cases are simply defined as any entity that experiences at least one crash and controls are those entities without a crash in a given period. In a "typical" case-control design, the attributes associated with single-crash segments are weighted

  3. Case-control vaccine effectiveness studies: Preparation, design, and enrollment of cases and controls.

    PubMed

    Verani, Jennifer R; Baqui, Abdullah H; Broome, Claire V; Cherian, Thomas; Cohen, Cheryl; Farrar, Jennifer L; Feikin, Daniel R; Groome, Michelle J; Hajjeh, Rana A; Johnson, Hope L; Madhi, Shabir A; Mulholland, Kim; O'Brien, Katherine L; Parashar, Umesh D; Patel, Manish M; Rodrigues, Laura C; Santosham, Mathuram; Scott, J Anthony; Smith, Peter G; Sommerfelt, Halvor; Tate, Jacqueline E; Victor, J Chris; Whitney, Cynthia G; Zaidi, Anita K; Zell, Elizabeth R

    2017-06-05

    Case-control studies are commonly used to evaluate effectiveness of licensed vaccines after deployment in public health programs. Such studies can provide policy-relevant data on vaccine performance under 'real world' conditions, contributing to the evidence base to support and sustain introduction of new vaccines. However, case-control studies do not measure the impact of vaccine introduction on disease at a population level, and are subject to bias and confounding, which may lead to inaccurate results that can misinform policy decisions. In 2012, a group of experts met to review recent experience with case-control studies evaluating the effectiveness of several vaccines; here we summarize the recommendations of that group regarding best practices for planning, design and enrollment of cases and controls. Rigorous planning and preparation should focus on understanding the study context including healthcare-seeking and vaccination practices. Case-control vaccine effectiveness studies are best carried out soon after vaccine introduction because high coverage creates strong potential for confounding. Endpoints specific to the vaccine target are preferable to non-specific clinical syndromes since the proportion of non-specific outcomes preventable through vaccination may vary over time and place, leading to potentially confusing results. Controls should be representative of the source population from which cases arise, and are generally recruited from the community or health facilities where cases are enrolled. Matching of controls to cases for potential confounding factors is commonly used, although should be reserved for a limited number of key variables believed to be linked to both vaccination and disease. Case-control vaccine effectiveness studies can provide information useful to guide policy decisions and vaccine development, however rigorous preparation and design is essential. Published by Elsevier Ltd.

  4. Adaptation of Chain Event Graphs for use with Case-Control Studies in Epidemiology.

    PubMed

    Keeble, Claire; Thwaites, Peter Adam; Barber, Stuart; Law, Graham Richard; Baxter, Paul David

    2017-09-26

    Case-control studies are used in epidemiology to try to uncover the causes of diseases, but are a retrospective study design known to suffer from non-participation and recall bias, which may explain their decreased popularity in recent years. Traditional analyses report usually only the odds ratio for given exposures and the binary disease status. Chain event graphs are a graphical representation of a statistical model derived from event trees which have been developed in artificial intelligence and statistics, and only recently introduced to the epidemiology literature. They are a modern Bayesian technique which enable prior knowledge to be incorporated into the data analysis using the agglomerative hierarchical clustering algorithm, used to form a suitable chain event graph. Additionally, they can account for missing data and be used to explore missingness mechanisms. Here we adapt the chain event graph framework to suit scenarios often encountered in case-control studies, to strengthen this study design which is time and financially efficient. We demonstrate eight adaptations to the graphs, which consist of two suitable for full case-control study analysis, four which can be used in interim analyses to explore biases, and two which aim to improve the ease and accuracy of analyses. The adaptations are illustrated with complete, reproducible, fully-interpreted examples, including the event tree and chain event graph. Chain event graphs are used here for the first time to summarise non-participation, data collection techniques, data reliability, and disease severity in case-control studies. We demonstrate how these features of a case-control study can be incorporated into the analysis to provide further insight, which can help to identify potential biases and lead to more accurate study results.

  5. Wandering spleen in children: multicenter retrospective study.

    PubMed

    Fiquet-Francois, Caroline; Belouadah, Mohamed; Ludot, Hugues; Defauw, Benoit; Mcheik, Jiad Noel; Bonnet, Jean Paul; Kanmegne, Charly Udozen; Weil, Dominique; Coupry, Lionel; Fremont, Benjamin; Becmeur, Francois; Lacreuse, Isabelle; Montupet, Philippe; Rahal, Eliane; Botto, Nathalie; Cheikhelard, Alaa; Sarnacki, Sabine; Petit, Thierry; Poli Merol, Marie Laurence

    2010-07-01

    Wandering spleen in children is a rare condition. The diagnosis is difficult, and any delay can cause splenic ischemia. An epidemiologic, semiological, and surgical diagnosis questionnaire on incidence of wandering spleen in children was sent to several French surgical teams. We report the results of this multicenter retrospective study. Fourteen cases (6 girls, 8 boys) were reported between 1984 and 2009; the age range varies between 1-day-old and 15 years; 86% were seen in the emergency department. Ninety-three percent had diffuse abdominal pain. For 57% of the cases, it was their first symptomatic episode of this type. No diagnosis was established based on the clinical results alone. All patients had presurgical imaging diagnosis. Open surgery was performed on 64% cases. Forty-three had splenectomy for splenic ischemia. Thirty-six percent had splenopexy, 14% had laparoscopic gastropexy, and 7% had spleen repositioning and regeneration. Complications were noted in 60% of the cases resulting in postsplenopexy splenic ischemia. Early diagnosis and surgery are the best guarantee for spleen preservation. Even if the choice of one technique, splenopexy or gastropexy, can be argued, gastropexy has the advantage of avoiding splenic manipulation and restoring proper physiologic anatomy. When there is no history of abdominal surgery, laparoscopy surgery seems the best procedure.

  6. Acute necrotizing pancreatitis: a multicenter study.

    PubMed

    Fernández-Cruz, L; Navarro, S; Valderrama, R; Sáenz, A; Guarner, L; Aparisi, L; Espi, A; Jaurietta, E; Marruecos, L; Gener, J

    1994-04-01

    A multicenter study of acute necrotizing pancreatitis (ANP) classified in accordance with the Balthazar criteria (grades D and E), has been performed in 12 teaching hospitals. A total of 233 patients were reviewed, and the mortality rate was 26.6%. The most common etiology was biliary pancreatitis (45.5%). Among the complications, shock, renal insufficiency, pulmonary insufficiency and hemorrhagic gastritis were associated with a mortality rate of 51-66%. Diffuse fluid collections were associated with a higher mortality rate (26.8%) than localized fluid collections (14.5%). In 106 patients with gallstone pancreatitis, early surgery was performed in 17, and 5 patients (29.4%) died. No mortality was observed in 32 patients with delayed surgery. Sphincterotomy was performed in 13 patients, and 4 (30.7%) died. Early surgery (necrosectomy and closed peritoneal lavage) was undertaken in 75 patients, with a mortality rate of 39%. In conclusion, the morbidity and mortality rates of ANP can be improved with proper monitoring, adequate supportive care and the judicious use of surgery based on clinical and morphological findings.

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

    PubMed

    Xiao, Ying; Zhao, Yubin; Xie, Yanming

    2011-10-01

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

  8. Multicenter prospective evaluation of dogs with trauma.

    PubMed

    Hall, Kelly E; Holowaychuk, Marie K; Sharp, Claire R; Reineke, Erica

    2014-02-01

    To determine hospital admission variables for dogs with trauma including values determined with scoring systems (animal trauma triage [ATT], modified Glasgow coma scale [MGCS], and acute patient physiologic and laboratory evaluation [APPLE] scores) and the usefulness of such variables for the prediction of outcome (death vs survival to hospital discharge). Prospective, multicenter, cohort study. 315 client-owned dogs. By use of a Web-based data capture system, trained personnel prospectively recorded admission ATT, MGCS, and APPLE scores; clinical and laboratory data; and outcome (death vs survival to discharge) for dogs with trauma at 4 veterinary teaching hospitals during an 8-week period. Cause of injury was most commonly blunt trauma (173/315 [54.9%]) followed by penetrating trauma (107/315 [34.0%]), or was unknown (35/315 [11.1%]). Of the 315 dogs, 285 (90.5%) survived to hospital discharge. When 16 dogs euthanized because of cost were excluded, dogs with blunt trauma were more likely to survive, compared with dogs with penetrating trauma (OR, 8.5). The ATT (OR, 2.0) and MGCS (OR, 0.47) scores and blood lactate concentration (OR, 1.5) at the time of hospital admission were predictive of outcome. Surgical procedures were performed for 157 (49.8%) dogs; surgery was associated with survival to discharge (OR, 7.1). Results indicated ATT and MGCS scores were useful for prediction of outcome for dogs evaluated because of trauma. Penetrating trauma, low blood lactate concentration, and performance of surgical procedures were predictive of survival to hospital discharge. The methods enabled collection of data for a large number of dogs in a short time.

  9. Canadian multicenter azidothymidine trial: AZT pharmacokinetics.

    PubMed

    Child, S; Montaner, J; Tsoukas, C; Fanning, M; Le, T; Wall, R A; Ruedy, J

    1991-01-01

    The study objective was to describe the pharmacokinetics of azidothymidine (AZT) in a large population of early, asymptomatic human immunodeficiency virus (HIV)-infected individuals. The study design was a multicenter, prospective, descriptive single-dose pharmacokinetic study. Each of 66 fasting, male, HIV-infected homosexuals older than 18 years of age and in CDC classifications II, III, and IVC2 received a single 400-mg oral dose of AZT with subsequent pharmacokinetic measurements performed during an 8-h period for AZT and its major metabolite, glucuronylazidothymidine (GAZT). Results were obtained in 65 patients (36 smokers, 29 nonsmokers), of whom 3 were noted to have hepatic dysfunction. In those with normal hepatic function, the following parameters were described: AZT, area under the curve (AUC) +/- SD, 9.9 +/- 5.7 microM.h, maximum concentration (Cmax) +/- SD, 7.3 +/- 4.7 microM; time to maximum concentration (Tmax) +/- SD, 0.93 +/- 0.42 h, and half-life (t1/2) +/- SD, 1.0 +/- 0.8 h. Corresponding values for GAZT were: AUC +/- SD 35.7 +/- 10.3 microM.h, Cmax +/- SD 21.3 +/- 7.3 microM, Tmax +/- SD 1.2 +/- 0.50 h, t1/2 +/- SD 0.98 +/- 0.62 h, No significant differences were found in comparisons of study site, CDC classification of disease, smokers versus nonsmokers, and in patients with hepatic dysfunction, although a higher AUC and earlier Cmax for AZT was noted in the latter group. It is concluded that AZT pharmacokinetics are similar in patients with early asymptomatic HIV disease when compared with previous reports in patients with later disease.(ABSTRACT TRUNCATED AT 250 WORDS)

  10. [Inguinofemoral hernia: multicenter study of surgical techniques].

    PubMed

    Porrero, José L; Sánchez-Cabezudo, Carlos; Bonachía, Oscar; López-Buenadicha, Adolfo; Sanjuánbenito, Alfonso; Hidalgo, Manuel

    2005-07-01

    The present study was performed by the Spanish Association of surgeons through its abdominal wall and sutures section. The aim was to determine the current situation of inguinofemoral hernias in Spain and was based on an anonymous multicenter study with the participation of various national hospitals. Fifty general surgery departments in distinct surgical centers throughout Spain responded to an anonymous survey in 2000. The survey gathered data on anesthetic features, surgical techniques and complications in the treatment of inguinofemoral hernias. Sixty-six percent of hospital centers had a specific abdominal wall unit and 24% performed laparoscopic hernia surgery. Prosthetic techniques (especially Lichtenstein) were the most frequently used in the treatment of primary inguinal hernia (72%) and recurrent hernia (100%). The most frequently used prosthetic material was polypropylene mesh (76%). Only 28% of the departments surveyed performed anatomic techniques in the repair of primary inguinal hernia (Shouldice and Bassini). The most frequent treatment for femoral hernia was the Lichtenstein "plug" (78%). Sixty-eight percent of the centers surveyed performed regional anesthesia, 18% used general anesthesia and only 14% used local anesthesia with sedation. Severe complications were found in 20% of departments. Clinical postoperative follow-up was performed in 96% of the centers and telephone follow-up was used in 4%. The recurrence rate was 1.2% for primary inguinal hernia, 2.7% for recurrent inguinal hernia and 0.3% for femoral hernia. In Spain the most commonly used surgical technique in the treatment of inguinal hernia is Lichtenstein hernioplasty under spinal anesthesia and with polypropylene prosthesis. The Lichtenstein plug is the most commonly used technique in the treatment of femoral hernia.

  11. A Data Management System for Multi-Phase Case-Control Studies

    PubMed Central

    Gibeau, Joanne M.; Steinfeldt, Lois C.; Stine, Mark J.; Tullis, Katherine V.; Lynch, H. Keith

    1983-01-01

    The design of a computerized system for the management of data in multi-phase epidemiologic case-control studies is described. Typical study phases include case-control selection, abstracting of data from medical records, and interview of study subjects or next of kin. In consultation with project personnel, requirements for the system were established: integration of data from all study phases into one data base, accurate follow-up of subjects through the study, sophisticated data editing capabilities, ready accessibility of specified programs to project personnel, and generation of current status and exception reports for project managment. SIR (Scientific Information Retrieval), a commercially available data base management system, was selected as the foundation of this system. The system forms a comprehensive data management system applicable to many types of public health research studies.

  12. Sequential tests for gene-environment interactions in matched case-control studies.

    PubMed

    Tweel, Ingeborg van der; Schipper, Maria

    2004-12-30

    The sample size necessary to detect a significant gene x environment interaction in an observational study can be large. For reasons of cost-effectiveness and efficient use of available biological samples we investigated the properties of sequential designs in matched case-control studies to test for both non-hierarchical and hierarchical interactions. We derived the test statistics Z and V and their characteristics when applied in a two-sided triangular test. Results of simulations show good agreement with theoretical values for V and the type I error. Power values were larger than their theoretical values for very large sample sizes. Median gain in efficiency was about 27 per cent. For a 'rare' phenotype gain in efficiency was larger when the alternative hypothesis was true than under the null hypothesis. Sequential designs lead to substantial efficiency gains in tests for interaction in matched case-control studies.

  13. The limitations of case-control studies in the detection of environmental carcinogens.

    PubMed Central

    Crombie, I K

    1981-01-01

    The ability of the case-control study to detect human carcinogens has been investigated theoretically for varying fractions of the population exposed to hazards carrying different relative risks. The method is shown to be useful for the investigation of factors to which exposure is widespread (for example, common foods or beverages) but it is of limited use for the study of uncommon types of exposure, such as those associated with occupation. The case-control study is unable to detect very small relative risks (less than 1.5) even where exposure is widespread and large numbers of cases of cancer are occurring in the population. The principal limitation of the method is the maximum number of cases which can be recruited and analysed. It will only be through large-scale collaborative multicentre or international studies that important risk factors will be detected. PMID:7338704

  14. Trypanosoma cruzi-associated cerebrovascular disease: a case-control study in Eastern Colombia.

    PubMed

    Leon-Sarmiento, Fidias E; Mendoza, Eder; Torres-Hillera, Martin; Pinto, Neyla; Prada, Janette; Silva, Clara A; Vera, Silvia J; Castillo, Erwin; Valderrama, Vladimir; Prada, Didier G; Bayona-Prieto, Jaime; Garcia, Ingrid

    2004-01-15

    Trypanosoma cruzi infection is a common cause of cardiopathy in South America leading it eventually to an established stroke; however, the association between T. cruzi infection itself and cerebrovascular disease is still unknown. We did a case-control study at Eastern Colombia and found that T. cruzi infection was more frequent and statistically significant in stroke cases (24.4%) than controls (1.9%), (Chi square: 21.72; OR: 16.13; 95% confidence interval (CI): 3.64-71.4; p<0.00001). After removing the seropositive patients with cardiological abnormalities, the significance still remained by multivariate analysis (p<0.05). This is the first case-control study that demonstrated a significant link between this infection and symptomatic cerebrovascular disease, mainly ischemic, regardless of cardiac abnormalities. Therefore, we recommend that patients with stroke must be screened for T. cruzi infection if they currently live or have lived in places where this parasite is considered endemic.

  15. An alternative hypothesis testing strategy for secondary phenotype data in case-control genetic association studies.

    PubMed

    Lutz, Sharon M; Hokanson, John E; Lange, Christoph

    2014-01-01

    Motivated by the challenges associated with accounting for the ascertainment when analyzing secondary phenotypes that are correlated with case-control status, Lin and Zeng have proposed a method that properly reflects the case-control sampling (Lin and Zeng, 2009). The Lin and Zeng method has the advantage of accurately estimating effect sizes for secondary phenotypes that are normally distributed or dichotomous. This method can be computationally intensive in practice under the null hypothesis when the likelihood surface that needs to be maximized can be relatively flat. We propose an extension of the Lin and Zeng method for hypothesis testing that uses proportional odds logistic regression to circumvent these computational issues. Through simulation studies, we compare the power and type-1 error rate of our method to standard approaches and Lin and Zeng's approach.

  16. A double robust approach to causal effects in case-control studies.

    PubMed

    Rose, Sherri; van der Laan, Mark

    2014-03-15

    In a recent issue of the Journal, VanderWeele and Vansteelandt (Am J Epidemiol. 2011;174(10):1197-1203) discussed an inverse probability weighting method for case-control studies that could be used to estimate an additive interaction effect, referred to as the "relative excess risk due to interaction." In this article, we reinforce the well-known disadvantages of inverse probability weighting and comment on the desirability of the described parameter. Further, we review an existing double robust estimator not considered by VanderWeele and Vansteelandt, the case-control-weighted targeted maximum likelihood estimator, which has improved properties in comparison with a previously described inverse-probability-weighted estimator. This targeted maximum likelihood estimator can be used to target various parameters of interest, and its implementation has been described previously for the risk difference, relative risk, and odds ratio.

  17. Matched case-control studies: a review of reported statistical methodology.

    PubMed

    Niven, Daniel J; Berthiaume, Luc R; Fick, Gordon H; Laupland, Kevin B

    2012-01-01

    Case-control studies are a common and efficient means of studying rare diseases or illnesses with long latency periods. Matching of cases and controls is frequently employed to control the effects of known potential confounding variables. The analysis of matched data requires specific statistical methods. The objective of this study was to determine the proportion of published, peer-reviewed matched case-control studies that used statistical methods appropriate for matched data. Using a comprehensive set of search criteria we identified 37 matched case-control studies for detailed analysis. Among these 37 articles, only 16 studies were analyzed with proper statistical techniques (43%). Studies that were properly analyzed were more likely to have included case patients with cancer and cardiovascular disease compared to those that did not use proper statistics (10/16 or 63%, versus 5/21 or 24%, P = 0.02). They were also more likely to have matched multiple controls for each case (14/16 or 88%, versus 13/21 or 62%, P = 0.08). In addition, studies with properly analyzed data were more likely to have been published in a journal with an impact factor listed in the top 100 according to the Journal Citation Reports index (12/16 or 69%, versus 1/21 or 5%, P ≤ 0.0001). The findings of this study raise concern that the majority of matched case-control studies report results that are derived from improper statistical analyses. This may lead to errors in estimating the relationship between a disease and exposure, as well as the incorrect adaptation of emerging medical literature.

  18. Population versus hospital controls for case-control studies on cancers in Chinese hospitals.

    PubMed

    Li, Lin; Zhang, Min; Holman, D'Arcy

    2011-12-15

    Correct control selection is crucial to the internal validity of case-control studies. Little information exists on differences between population and hospital controls in case-control studies on cancers in Chinese hospital setting. We conducted three parallel case-control studies on leukemia, breast and colorectal cancers in China between 2009 and 2010, using population and hospital controls to separately match 540 incident cases by age, gender and residency at a 1:1 ratio. Demographic and lifestyle factors were measured using a validated questionnaire in face-to-face interview. Odds ratios (ORs) and 95% confidence intervals (CIs) were obtained using conditional logistic regression analyses. The two control groups had closely similar exposure distributions of 15 out of 16 factors, with the only exception being that hospital controls were less likely to have a BMI ≥ 25 (OR = 0.71, 95% CI: 0.54, 0.93). For exposure of green tea drinking, the adjusted ORs (95% CIs) comparing green tealeaves intake ≥ 1000 grams annually with non-drinkers were 0.51 (0.31, 0.83) and 0.21 (0.27, 0.74) for three cancers combined, 0.06 (0.01, 0.61) and 0.07 (0.01, 0.47) for breast cancer, 0.52 (0.29, 0.94) and 0.45 (0.25, 0.82) for colorectal cancer, 0.65 (0.08, 5.63) and 0.57 (0.07, 4.79) for leukemia using hospital and population controls respectively. The study found that hospital controls were comparable with population controls for most demographic characteristics and lifestyle factors measured, but there was a slight difference between the two control groups. Hospital outpatients provide a satisfactory control group in hospital-based case-control study in the Chinese hospital setting.

  19. Matched case-control studies: a review of reported statistical methodology

    PubMed Central

    Niven, Daniel J; Berthiaume, Luc R; Fick, Gordon H; Laupland, Kevin B

    2012-01-01

    Background Case-control studies are a common and efficient means of studying rare diseases or illnesses with long latency periods. Matching of cases and controls is frequently employed to control the effects of known potential confounding variables. The analysis of matched data requires specific statistical methods. Methods The objective of this study was to determine the proportion of published, peer-reviewed matched case-control studies that used statistical methods appropriate for matched data. Using a comprehensive set of search criteria we identified 37 matched case-control studies for detailed analysis. Results Among these 37 articles, only 16 studies were analyzed with proper statistical techniques (43%). Studies that were properly analyzed were more likely to have included case patients with cancer and cardiovascular disease compared to those that did not use proper statistics (10/16 or 63%, versus 5/21 or 24%, P = 0.02). They were also more likely to have matched multiple controls for each case (14/16 or 88%, versus 13/21 or 62%, P = 0.08). In addition, studies with properly analyzed data were more likely to have been published in a journal with an impact factor listed in the top 100 according to the Journal Citation Reports index (12/16 or 69%, versus 1/21 or 5%, P ≤ 0.0001). Conclusion The findings of this study raise concern that the majority of matched case-control studies report results that are derived from improper statistical analyses. This may lead to errors in estimating the relationship between a disease and exposure, as well as the incorrect adaptation of emerging medical literature. PMID:22570570

  20. 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

  1. Polychlorinated Biphenyls, Organochlorines & PD Risk: A Case Control Study in Alaska

    DTIC Science & Technology

    2009-05-01

    Organochlorines & PD Risk: A Case Control Study in Alaska 5b. GRANT NUMBER W81XWH-04-1-0490 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT...biphenyl (PCBs) residues, organochlorine pesticides and methylmercury with PD. The hypothesis is that increased exposure to these compounds will be...Parkinson’s disease, polychlorinated biphenyl, organochlorine pesticides, methylmercury, Alaska natives, neurodegeneration 16. SECURITY

  2. Polychlorinated Biphenyls, Organochlorines & PD Risk: A Case Control Study in Alaskan Natives

    DTIC Science & Technology

    2011-05-01

    1-0490 TITLE: Polychlorinated Biphenyls, Organochlorines & PD Risk: A Case Control Study in Alaskan Natives PRINCIPAL INVESTIGATOR...Polychlorinated Biphenyls, Organochlorines & PD Risk: A Case 5a. CONTRACT NUMBER W81XWH-04-1-0490 Control Study in Alaskan Natives 5b. GRANT NUMBER...to pol ychlorinated biphenyl (PCBs) residues, organochlorine pesticides and methylmercury with PD. The hy pothesis is that increased exposure to t

  3. Polychlorinated Biphenyls, Organochlorines & PD Risk: A Case Control Study in Alaska

    DTIC Science & Technology

    2010-05-01

    TITLE: Polychlorinated Biphenyls, Organochlorines & PD Risk: A Case Control Study in Alaska PRINCIPAL INVESTIGATOR: Caroline M. Tanner, M.D...2010 4. TITLE AND SUBTITLE Polychlorinated Biphenyls, Organochlorines & PD Risk: A Case 5a. CONTRACT NUMBER W81XWH-04-1-0490 Control Study in...now in progress in Anchorage. 15. SUBJECT TERMS Parkinson’s disease, Polychlorinated biphenyl, Organochlorine pesticides, Methylmercury, Alaska

  4. Acute myeloid leukemia in adults: a case-control study in Yorkshire.

    PubMed

    Cartwright, R A; Darwin, C; McKinney, P A; Roberts, B; Richards, I D; Bird, C C

    1988-10-01

    This paper reports the results of a case-control analysis of 161 cases of acute myeloid leukemia and 310 matched hospital controls. The patients were interviewed between 1982 and 1986. The study shows a weak association for cases with previous malignant disease. Furnace workers show excess risks. Urticaria and vertigo are in excess, as well as some aspects of family medical histories, including multiple sclerosis and cases of leukemia/lymphoma in blood relations.

  5. Accurate liability estimation improves power in ascertained case-control studies.

    PubMed

    Weissbrod, Omer; Lippert, Christoph; Geiger, Dan; Heckerman, David

    2015-04-01

    Linear mixed models (LMMs) have emerged as the method of choice for confounded genome-wide association studies. However, the performance of LMMs in nonrandomly ascertained case-control studies deteriorates with increasing sample size. We propose a framework called LEAP (liability estimator as a phenotype; https://github.com/omerwe/LEAP) that tests for association with estimated latent values corresponding to severity of phenotype, and we demonstrate that this can lead to a substantial power increase.

  6. Epistatic Module Detection for Case-Control Studies: A Bayesian Model with a Gibbs Sampling Strategy

    PubMed Central

    Tang, Wanwan; Wu, Xuebing; Jiang, Rui; Li, Yanda

    2009-01-01

    The detection of epistatic interactive effects of multiple genetic variants on the susceptibility of human complex diseases is a great challenge in genome-wide association studies (GWAS). Although methods have been proposed to identify such interactions, the lack of an explicit definition of epistatic effects, together with computational difficulties, makes the development of new methods indispensable. In this paper, we introduce epistatic modules to describe epistatic interactive effects of multiple loci on diseases. On the basis of this notion, we put forward a Bayesian marker partition model to explain observed case-control data, and we develop a Gibbs sampling strategy to facilitate the detection of epistatic modules. Comparisons of the proposed approach with three existing methods on seven simulated disease models demonstrate the superior performance of our approach. When applied to a genome-wide case-control data set for Age-related Macular Degeneration (AMD), the proposed approach successfully identifies two known susceptible loci and suggests that a combination of two other loci—one in the gene SGCD and the other in SCAPER—is associated with the disease. Further functional analysis supports the speculation that the interaction of these two genetic variants may be responsible for the susceptibility of AMD. When applied to a genome-wide case-control data set for Parkinson's disease, the proposed method identifies seven suspicious loci that may contribute independently to the disease. PMID:19412524

  7. Questionnaires for collecting detailed occupational information for community-based case control studies.

    PubMed

    Stewart, P A; Stewart, W F; Siemiatycki, J; Heineman, E F; Dosemeci, M

    1998-01-01

    In case control studies, collection of information on the workplace environment has generally been limited to self-reports of exposures or to job title, type of employer, and the dates the jobs were held, supplemented sometimes by work activities. This information, however, may be insufficient to assess the potential and level of exposure accurately due to recall difficulties and the variability of exposures within a job. A solution to this problem is to use job-specific questionnaires. The organization of a series of such questionnaires developed for a case control study of brain tumors is described. Three types of questionnaires, or modules, were developed, task-based, industry-based, and modules based on jobs with nonspecific types of tasks (e.g., laborer). The format of these modules starts with questions on the general work environment (type of employer) and proceeds to questions on tasks. More detailed information is then gathered on materials and equipment used, sensory descriptions, dermal exposure, work practices, engineering controls, and personal protective equipment use. The questionnaires cover a wide variety of exposures including solvents, heavy metals, polycyclic aromatic hydrocarbons, machining fluids, electromagnetic frequency fields, and many other exposures and, therefore, can be used in other case control studies.

  8. Sleep and Parkinson's disease: a review of case-control polysomnography studies.

    PubMed

    Peeraully, Tasneem; Yong, Ming-Hui; Chokroverty, Sudhansu; Tan, Eng-King

    2012-12-01

    The link between Parkinson's disease (PD) and certain primary sleep disorders has yet to be clarified. We performed a systematic review of case-control polysomnography studies to evaluate the relationship between PD and sleep disorders. A PubMed literature search and bibliography review yielded 15 case-control polysomnography studies in patients with PD. Studies differed by recruitment methods, duration of polysomnography monitoring, and sleep parameters measured. Subjective sleepiness was greater in patients than controls (50%-66% vs 2.9%-12%) despite lack of objective increase in daytime sleepiness by mean sleep latency testing. The 4 case-control polysomnography studies investigating rapid eye movement behavior disorder support a higher prevalence in PD (0%-47% vs 0%-1.8% in controls), although differences in diagnostic criteria hamper interpretation. The preponderance of evidence did not support an increased incidence of obstructive sleep apnea (27%-60% vs 13%-65%) or periodic leg movements of sleep in patients compared to controls. Adequately powered, prospective studies with uniform methodology and healthy controls are needed to further address the association and pathophysiological significance between PD and sleep problems.

  9. On estimation of time-dependent attributable fraction from population-based case-control studies.

    PubMed

    Zhao, Wei; Chen, Ying Qing; Hsu, Li

    2017-01-18

    Population attributable fraction (PAF) is widely used to quantify the disease burden associated with a modifiable exposure in a population. It has been extended to a time-varying measure that provides additional information on when and how the exposure's impact varies over time for cohort studies. However, there is no estimation procedure for PAF using data that are collected from population-based case-control studies, which, because of time and cost efficiency, are commonly used for studying genetic and environmental risk factors of disease incidences. In this article, we show that time-varying PAF is identifiable from a case-control study and develop a novel estimator of PAF. Our estimator combines odds ratio estimates from logistic regression models and density estimates of the risk factor distribution conditional on failure times in cases from a kernel smoother. The proposed estimator is shown to be consistent and asymptotically normal with asymptotic variance that can be estimated empirically from the data. Simulation studies demonstrate that the proposed estimator performs well in finite sample sizes. Finally, the method is illustrated by a population-based case-control study of colorectal cancer.

  10. Impact of waning acquired immunity and asymptomatic infections on case-control studies for enteric pathogens.

    PubMed

    Havelaar, Arie H; Swart, Arno

    2016-12-01

    Case-control studies of outbreaks and of sporadic cases of infectious diseases may provide a biased estimate of the infection rate ratio, due to selecting controls that are not at risk of disease. We use a dynamic mathematical model to explore biases introduced in results drawn from case-control studies of enteric pathogens by waning and boosting of immunity, and by asymptomatic infections, using Campylobacter jejuni as an example. Individuals in the population are either susceptible (at risk of infection and disease), fully protected (not at risk of either) or partially protected (at risk of infection but not of disease). The force of infection is a function of the exposure frequency and the exposure dose. We show that the observed disease odds ratios are indeed strongly biased towards the null, i.e. much lower than the infection rate ratio, and furthermore even not proportional to it. The bias could theoretically be controlled by sampling controls only from the reservoir of susceptible individuals. The population at risk is in a dynamic equilibrium, and cannot be identified as those who are not and have never experienced disease. Individual-level samples to measure protective immunity would be required, complicating the design, cost and execution of case-control studies.

  11. Using cumulative sums of martingale residuals for model checking in nested case-control studies.

    PubMed

    Borgan, Ørnulf; Zhang, Ying

    2015-09-01

    Standard use of Cox regression requires collection of covariate information for all individuals in a cohort even when only a small fraction of them experiences the event of interest (fail). This may be very expensive for large cohorts. Further in biomarker studies, it will imply a waste of valuable biological material that one may want to save for future studies. A nested case-control study offers a useful alternative. For this design, covariate information is only needed for the failing individuals (cases) and a sample of controls selected from the cases' at-risk sets. Methods based on martingale residuals are useful for checking the fit of Cox's regression model for cohort data. But similar methods have so far not been developed for nested case-control data. In this article, it is described how one may define martingale residuals for nested case-control data, and it is shown how plots and tests based on cumulative sums of martingale residuals may be used to check model fit. The plots and tests may be obtained using available software.

  12. 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

  13. Estimating marginal causal effects in a secondary analysis of case-control data.

    PubMed

    Persson, Emma; Waernbaum, Ingeborg; Lind, Torbjörn

    2017-03-09

    When an initial case-control study is performed, data can be used in a secondary analysis to evaluate the effect of the case-defining event on later outcomes. In this paper, we study the example in which the role of the event is changed from a response variable to a treatment of interest. If the aim is to estimate marginal effects, such as average effects in the population, the sampling scheme needs to be adjusted for. We study estimators of the average effect of the treatment in a secondary analysis of matched and unmatched case-control data where the probability of being a case is known. For a general class of estimators, we show the components of the bias resulting from ignoring the sampling scheme and demonstrate a design-weighted matching estimator of the average causal effect. In simulations, the finite sample properties of the design-weighted matching estimator are studied. Using a Swedish diabetes incidence register with a matched case-control design, we study the effect of childhood onset diabetes on the use of antidepressant medication as an adult. Copyright © 2017 John Wiley & Sons, Ltd.

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

    PubMed

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

    2017-02-01

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

  15. CONTROL FUNCTION ASSISTED IPW ESTIMATION WITH A SECONDARY OUTCOME IN CASE-CONTROL STUDIES.

    PubMed

    Sofer, Tamar; Cornelis, Marilyn C; Kraft, Peter; Tchetgen Tchetgen, Eric J

    2017-04-01

    Case-control studies are designed towards studying associations between risk factors and a single, primary outcome. Information about additional, secondary outcomes is also collected, but association studies targeting such secondary outcomes should account for the case-control sampling scheme, or otherwise results may be biased. Often, one uses inverse probability weighted (IPW) estimators to estimate population effects in such studies. IPW estimators are robust, as they only require correct specification of the mean regression model of the secondary outcome on covariates, and knowledge of the disease prevalence. However, IPW estimators are inefficient relative to estimators that make additional assumptions about the data generating mechanism. We propose a class of estimators for the effect of risk factors on a secondary outcome in case-control studies that combine IPW with an additional modeling assumption: specification of the disease outcome probability model. We incorporate this model via a mean zero control function. We derive the class of all regular and asymptotically linear estimators corresponding to our modeling assumption, when the secondary outcome mean is modeled using either the identity or the log link. We find the efficient estimator in our class of estimators and show that it reduces to standard IPW when the model for the primary disease outcome is unrestricted, and is more efficient than standard IPW when the model is either parametric or semiparametric.

  16. Combining matched and unmatched control groups in case-control studies.

    PubMed

    le Cessie, Saskia; Nagelkerke, Nico; Rosendaal, Frits R; van Stralen, Karlijn J; Pomp, Elisabeth R; van Houwelingen, Hans C

    2008-11-15

    Multiple control groups in case-control studies are used to control for different sources of confounding. For example, cases can be contrasted with matched controls to adjust for multiple genetic or unknown lifestyle factors and simultaneously contrasted with an unmatched population-based control group. Inclusion of different control groups for a single exposure analysis yields several estimates of the odds ratio, all using only part of the data. Here the authors introduce an easy way to combine odds ratios from several case-control analyses with the same cases. The approach is based upon methods used for meta-analysis but takes into account the fact that the same cases are used and that the estimated odds ratios are therefore correlated. Two ways of estimating this correlation are discussed: sandwich methodology and the bootstrap. Confidence intervals for the pooled estimates and a test for checking whether the odds ratios in the separate case-control studies differ significantly are derived. The performance of the method is studied by simulation and by applying the methods to a large study on risk factors for thrombosis, the MEGA Study (1999-2004), wherein cases with first venous thrombosis were included with a matched control group of partners and an unmatched population-based control group.

  17. Exposure enriched case-control (EECC) design for the assessment of gene-environment interaction

    PubMed Central

    Carroll, Raymond J.; Diao, Nancy; Christiani, David C.; Ryan, Louise M.

    2016-01-01

    Genetic susceptibility and environmental exposure both play an important role in the aetiology of many diseases. Case-control studies are often the first choice to explore the joint influence of genetic and environmental factors on the risk of developing a rare disease. In practice, however, such studies may have limited power, especially when susceptibility genes are rare and exposure distributions are highly skewed. We propose a variant of the classical case-control study, the exposure enriched case-control (EECC) design, where not only cases, but also high (or low) exposed individuals are oversampled, depending on the skewness of the exposure distribution. Of course, a traditional logistic regression model is no longer valid and results in biased parameter estimation. We show that addition of a simple covariate to the regression model removes this bias and yields reliable estimates of main and interaction effects of interest. We also discuss optimal design, showing that judicious over-sampling of high/low exposed individuals can boost study power considerably. We illustrate our results using data from a study involving arsenic exposure and detoxification genes in Bangladesh. PMID:27313007

  18. Valid statistical inference methods for a case-control study with missing data.

    PubMed

    Tian, Guo-Liang; Zhang, Chi; Jiang, Xuejun

    2016-05-19

    The main objective of this paper is to derive the valid sampling distribution of the observed counts in a case-control study with missing data under the assumption of missing at random by employing the conditional sampling method and the mechanism augmentation method. The proposed sampling distribution, called the case-control sampling distribution, can be used to calculate the standard errors of the maximum likelihood estimates of parameters via the Fisher information matrix and to generate independent samples for constructing small-sample bootstrap confidence intervals. Theoretical comparisons of the new case-control sampling distribution with two existing sampling distributions exhibit a large difference. Simulations are conducted to investigate the influence of the three different sampling distributions on statistical inferences. One finding is that the conclusion by the Wald test for testing independency under the two existing sampling distributions could be completely different (even contradictory) from the Wald test for testing the equality of the success probabilities in control/case groups under the proposed distribution. A real cervical cancer data set is used to illustrate the proposed statistical methods.

  19. Taurodontism in children with hypodontia and supernumerary teeth: a case control study.

    PubMed

    Kan, Wayne Y W; Seow, W Kim; Holcombe, Trevor

    2010-01-01

    The aim of the present investigation was to compare the prevalence of taurodontism in the permanent mandibular first molars of nonsyndromic children with hypodontia and supernumerary teeth with age- and gender-matched controls. The crown-body root ratios of the permanent first molars were determined from orthopantomograms of 83 children with hypodontia (> or =1 missing teeth) and 37 children with supernumerary teeth (> or =1 extra teeth) compared with normal case controls. In children with hypodontia, only girls showed a significantly higher tendency for taurodontism compared to case controls (P=.003), while boys with hypodontia showed a similar prevalence of taurodontism as controls (P=.83). Children with multiple missing teeth were significantly more susceptible to taurodontism than children with a single missing tooth (P=.004). By contrast, the prevalence of taurodontism in children with supernumerary teeth was not significantly different from that of controls. Compared to normal case controls, children with nonsyndromic hypodontia are more likely to show taurodontism of the permanent first molar teeth whereas children with nonsyndromic supernumerary teeth are not.

  20. Determining exposure underreporting in pharmacoepidemiologic case-control studies: methods and example.

    PubMed

    Lane, D A; Kramer, M S

    1999-12-01

    Many pharmacoepidemiologic case-control studies have to rely on what their subjects relate about the drugs to which they have been exposed and the durations of exposure. There is often good reason to suppose that not all exposures are actually reported and to suspect reporting rates may differ between cases and controls. We introduce two procedures designed to determine the extent of underreporting of exposures. These procedures make use of data from the case-control study itself, as well as sales, demographic and market research data for a reference population to which study subjects belong. We apply these procedures to data from the International Primary Pulmonary Hypertension Study (IPPHS) linking anorexigens with PPH. We show that exposures to the anorectic agent dexfenfluramine beginning in or before 1989 were highly significantly underrepresented in the data for IPPHS controls, relative to exposures beginning after 1989 (P<0.01); there is no corresponding evidence for relative underrepresentation of early exposure for IPPHS cases. However, data on control exposures from 1990 to 1992 are consistent with the hypothesis that these exposures were not underreported to the IPPHS. Subject to certain key modeling assumptions and the availability of some supplemental data, it is possible to investigate the extent of underreporting of exposure in a pharmacoepidemiologic case-control study and in particular to determine if study results are likely to have been affected by recall bias.

  1. Multivariate multidistance tests for high-dimensional low sample size case-control studies.

    PubMed

    Marozzi, Marco

    2015-04-30

    A class of multivariate tests for case-control studies with high-dimensional low sample size data and with complex dependence structure, which are common in medical imaging and molecular biology, is proposed. The tests can be applied when the number of variables is much larger than the number of subjects and when the underlying population distributions are heavy-tailed or skewed. As a motivating application, we consider a case-control study where phase-contrast cinematic cardiovascular magnetic resonance imaging has been used to compare many cardiovascular characteristics of young healthy smokers and young healthy non-smokers. The tests are based on the combination of tests on interpoint distances. It is theoretically proved that the tests are exact, unbiased and consistent. It is shown that the tests are very powerful under normal, heavy-tailed and skewed distributions. The tests can also be applied to case-control studies with high-dimensional low sample size data from other medical imaging techniques (like computed tomography or X-ray radiography), chemometrics and microarray data (proteomics and transcriptomics).

  2. Urinary proteins, vitamin D and genetic polymorphisms as risk factors for febrile urinary tract infection and relation with bacteremia: a case control study.

    PubMed

    van der Starre, Willize E; van Nieuwkoop, Cees; Thomson, Uginia; Zijderveld-Voshart, Marleen S M; Koopman, Jan Pieter R; van der Reijden, Tanny J K; van Dissel, Jaap T; van de Vosse, Esther

    2015-01-01

    Febrile urinary tract infection (UTI) is a common bacterial disease that may lead to substantial morbidity and mortality especially among the elderly. Little is known about biomarkers that predict a complicated course. Our aim was to determine the role of certain urinary cytokines or antimicrobial proteins, plasma vitamin D level, and genetic variation in host defense of febrile UTI and its relation with bacteremia. A case-control study. Out of a cohort of consecutive adults with febrile UTI (n = 787) included in a multi-center observational cohort study, 46 cases with bacteremic E.coli UTI and 45 cases with non-bacteremic E.coli UTI were randomly selected and compared to 46 controls. Urinary IL-6, IL-8, LL37, β-defensin 2 and uromodulin as well as plasma 25-hydroxyvitamin D were measured. In 440 controls and 707 UTI patients polymorphisms were genotyped in the genes CXCR1, DEFA4, DEFB1, IL6, IL8, MYD88, UMOD, TIRAP, TLR1, TLR2, TLR5 and TNF. IL-6, IL-8, and LL37 are different between controls and UTI patients, although these proteins do not distinguish between patients with and without bacteremia. While uromodulin did not differ between groups, inability to produce uromodulin is more common in patients with bacteremia. Most participants in the study, including the controls, had insufficient vitamin D and, at least in winter, UTI patients have lower vitamin D than controls. Associations were found between the CC genotype of IL6 SNP rs1800795 and occurrence of bacteremia and between TLR5 SNP rs5744168 and protection from UTI. The rare GG genotype of IL6 SNP rs1800795 was associated with higher β-defensin 2 production. Although no biomarker was able to distinguish between UTI with or without bacteremia, two risk factors for bacteremia were identified. These were inability to produce uromodulin and an IL6 rs1800795 genotype.

  3. Risk factors associated with non-alcoholic fatty liver disease in subjects from primary care units. A case-control study

    PubMed Central

    Caballería, Llorenç; Auladell, Ma Antonia; Torán, Pere; Pera, Guillem; Miranda, Dolores; Alumà, Alba; Casas, José Dario; Muñoz, Laura; Sanchez, Carmen; Tibau, Albert; Birules, Marti; Canut, Santiago; Bernad, Jesús; Aubà, Josep; Aizpurua, Miren Maite; Alcaraz, Enriqueta

    2008-01-01

    Background Non alcoholic fatty liver disease (NAFL) consists in the accumulation of fat vacuoles in the cytoplasm of hepatocytes. Many etiologic factors are associated with NAFL, such as, the metabolic syndrome factors, medications, bariatric surgery, nutritional disorders. However, very little information is available on the clinical relevance of this disorder as a health problem in the general population. Methods and design The aim of the study is establish the risk factors most frequently associated with NAFL in a general adult population assigned to the primary care units and to investigate the relationship between each component of the metabolic syndrome and the risk of having a NAFL. A population based case-control, observational and multicenter study will be carried out in 18 primary care units from the "Area de Gestión del Barcelonés Nord y Maresme" (Barcelona) attending a population of 360,000 inhabitants and will include 326 cases and 370 controls. Cases are defined as all subjects fulfilling the inclusion criteria and with evidence of fatty liver in an abdominal ultrasonography performed for any reason. One control will be randomly selected for each case from the population, matched for age, gender and primary care center. Controls with fatty liver or other liver diseases will be excluded. All cases and controls will be asked about previous hepatic diseases, consumption of alcohol, smoking and drugs, and a physical examination, biochemical analyses including liver function tests, the different components of the metabolic syndrome and the HAIR score will also be performed. Paired controls will also undergo an abdominal ultrasonography. Discussion This study will attempt to determine the factors most frequently associated with the presence of NAFL investigate the relationship between the metabolic syndrome and the risk of fatty liver and study the influence of the different primary care professionals in avoiding the evolution of the disease. PMID

  4. 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. Copyright © 2010 Elsevier Ltd. All rights reserved.

  5. Multicenter observational prehospital resuscitation on helicopter study.

    PubMed

    Holcomb, John B; Swartz, Michael D; DeSantis, Stacia M; Greene, Thomas J; Fox, Erin E; Stein, Deborah M; Bulger, Eileen M; Kerby, Jeffrey D; Goodman, Michael; Schreiber, Martin A; Zielinski, Martin D; O'Keeffe, Terence; Inaba, Kenji; Tomasek, Jeffrey S; Podbielski, Jeanette M; Appana, Savitri N; Yi, Misung; Wade, Charles E

    2017-07-01

    at any time point, although only 10% of the high-risk sample were able to be matched. Because of the unexpected imbalance in systolic blood pressure, Glasgow Coma Scale, and Injury Severity Score between systems with and without blood products on helicopters, matching was limited, and the results of this study are inconclusive. With few units transfused to each patient and small outcome differences between groups, it is likely large, multicenter, randomized studies will be required to detect survival differences in this important population. Level II.

  6. Prospective Multicenter International Surveillance of Azole Resistance in Aspergillus fumigatus

    PubMed Central

    Arendrup, M.C.; Warris, A.; Lagrou, K.; Pelloux, H.; Hauser, P.M.; Chryssanthou, E.; Mellado, E.; Kidd, S.E.; Tortorano, A.M.; Dannaoui, E.; Gaustad, P.; Baddley, J.W.; Uekötter, A.; Lass-Flörl, C.; Klimko, N.; Moore, C.B.; Denning, D.W.; Pasqualotto, A.C.; Kibbler, C.; Arikan-Akdagli, S.; Andes, D.; Meletiadis, J.; Naumiuk, L.; Nucci, M.; Melchers, W.J.G.; Verweij, P.E.

    2015-01-01

    To investigate azole resistance in clinical Aspergillus isolates, we conducted prospective multicenter international surveillance. A total of 3,788 Aspergillus isolates were screened in 22 centers from 19 countries. Azole-resistant A. fumigatus was more frequently found (3.2% prevalence) than previously acknowledged, causing resistant invasive and noninvasive aspergillosis and severely compromising clinical use of azoles. PMID:25988348

  7. Study designs may influence results: the problems with questionnaire-based case-control studies on the epidemiology of glioma.

    PubMed

    Johansen, Christoffer; Schüz, Joachim; Andreasen, Anne-Marie Serena; Dalton, Susanne Oksbjerg

    2017-03-28

    Glioma is a rare brain tumour with a very poor prognosis and the search for modifiable factors is intense. We reviewed the literature concerning risk factors for glioma obtained in case-control designed epidemiological studies in order to discuss the influence of this methodology on the observed results. When reviewing the association between three exposures, medical radiation, exogenous hormone use and allergy, we critically appraised the evidence from both case-control and cohort studies. For medical radiation and hormone replacement therapy (HRT), questionnaire-based case-control studies appeared to show an inverse association, whereas nested case-control and cohort studies showed no association. For allergies, the inverse association was observed irrespective of study design. We recommend that the questionnaire-based case-control design be placed lower in the hierarchy of studies for establishing cause-and-effect for diseases such as glioma. We suggest that a state-of-the-art case-control study should, as a minimum, be accompanied by extensive validation of the exposure assessment methods and the representativeness of the study sample with regard to the exposures of interest. Otherwise, such studies cannot be regarded as 'hypothesis testing' but only 'hypothesis generating'. We consider that this holds true for all questionnaire-based case-control studies on cancer and other chronic diseases, although perhaps not to the same extent for each exposure-outcome combination.

  8. Performance of case-control rare copy number variation annotation in classification of autism

    PubMed Central

    2015-01-01

    Background A substantial proportion of Autism Spectrum Disorder (ASD) risk resides in de novo germline and rare inherited genetic variation. In particular, rare copy number variation (CNV) contributes to ASD risk in up to 10% of ASD subjects. Despite the striking degree of genetic heterogeneity, case-control studies have detected specific burden of rare disruptive CNV for neuronal and neurodevelopmental pathways. Here, we used machine learning methods to classify ASD subjects and controls, based on rare CNV data and comprehensive gene annotations. We investigated performance of different methods and estimated the percentage of ASD subjects that could be reliably classified based on presumed etiologic CNV they carry. Results We analyzed 1,892 Caucasian ASD subjects and 2,342 matched controls. Rare CNVs (frequency 1% or less) were detected using Illumina 1M and 1M-Duo BeadChips. Conditional Inference Forest (CF) typically performed as well as or better than other classification methods. We found a maximum AUC (area under the ROC curve) of 0.533 when considering all ASD subjects with rare genic CNVs, corresponding to 7.9% correctly classified ASD subjects and less than 3% incorrectly classified controls; performance was significantly higher when considering only subjects harboring de novo or pathogenic CNVs. We also found rare losses to be more predictive than gains and that curated neurally-relevant annotations (brain expression, synaptic components and neurodevelopmental phenotypes) outperform Gene Ontology and pathway-based annotations. Conclusions CF is an optimal classification approach for case-control rare CNV data and it can be used to prioritize subjects with variants potentially contributing to ASD risk not yet recognized. The neurally-relevant annotations used in this study could be successfully applied to rare CNV case-control data-sets for other neuropsychiatric disorders. PMID:25783485

  9. KRAS mutations in blood circulating cell-free DNA: a pancreatic cancer case-control

    PubMed Central

    Le Calvez-Kelm, Florence; Foll, Matthieu; Wozniak, Magdalena B.; Delhomme, Tiffany M.; Durand, Geoffroy; Chopard, Priscilia; Pertesi, Maroulio; Fabianova, Eleonora; Adamcakova, Zora; Holcatova, Ivana; Foretova, Lenka; Janout, Vladimir; Vallee, Maxime P.; Rinaldi, Sabina; Brennan, Paul; McKay, James D.; Byrnes, Graham B.; Scelo, Ghislaine

    2016-01-01

    The utility of KRAS mutations in plasma circulating cell-free DNA (cfDNA) samples as non-invasive biomarkers for the detection of pancreatic cancer has never been evaluated in a large case-control series. We applied a KRAS amplicon-based deep sequencing strategy combined with analytical pipeline specifically designed for the detection of low-abundance mutations to screen plasma samples of 437 pancreatic cancer cases, 141 chronic pancreatitis subjects, and 394 healthy controls. We detected mutations in 21.1% (N=92) of cases, of whom 82 (89.1%) carried at least one mutation at hotspot codons 12, 13 or 61, with mutant allelic fractions from 0.08% to 79%. Advanced stages were associated with an increased proportion of detection, with KRAS cfDNA mutations detected in 10.3%, 17,5% and 33.3% of cases with local, regional and systemic stages, respectively. We also detected KRAS cfDNA mutations in 3.7% (N=14) of healthy controls and in 4.3% (N=6) of subjects with chronic pancreatitis, but at significantly lower allelic fractions than in cases. Combining cfDNA KRAS mutations and CA19-9 plasma levels on a limited set of case-control samples did not improve the overall performance of the biomarkers as compared to CA19-9 alone. Whether the limited sensitivity and specificity observed in our series of KRAS mutations in plasma cfDNA as biomarkers for pancreatic cancer detection are attributable to methodological limitations or to the biology of cfDNA should be further assessed in large case-control series. PMID:27705932

  10. A population-based case-control study of radiofrequency exposure in relation to childhood neoplasm.

    PubMed

    Li, Chung-Yi; Liu, Chih-Ching; Chang, Ya-Hui; Chou, Li-Ping; Ko, Ming-Chung

    2012-10-01

    This population-based case-control study in Taiwan considered incident cases aged 15 years or less and admitted in 2003 to 2007 for all neoplasm (ICD-9-CM: 140-239) (n=2606), including 939 leukemia and 394 brain neoplasm cases. Controls were randomly selected, with a case/control ratio of 1:30 and matched on year of birth, from all non-neoplasm children insured in the same year when the index case was admitted. Annual summarized power (ASP, watt-year) was calculated for each of the 71,185 mobile phone base stations (MPBS) in service between 1998 and 2007. Then, the annual power density (APD, watt-year/km(2)) of each township (n=367) was computed as a ratio of the total ASP of all MPBS in a township to the area of that particular township. Exposure of each study subject to radio frequency (RF) was indicated by the averaged APD within 5 years prior to the neoplasm diagnosis (cases) or July 1st of the year when the index case was admitted (controls) in the township where the subject lived. Unconditional logistic regression model with generalized estimation equation was employed to calculate the covariate-adjusted odds ratio [AOR] of childhood neoplasm in relation to RF exposure. A higher than median averaged APD (approximately 168 WYs/km(2)) was significantly associated with an increased AOR for all neoplasms (1.13; 1.01 to 1.28), but not for leukemia (1.23; 0.99 to 1.52) or brain neoplasm (1.14, 0.83 to 1.55). This study noted a significantly increased risk of all neoplasms in children with higher-than-median RF exposure to MPBS. The slightly elevated risk was seen for leukemia and brain neoplasm, but was not statistically significant. These results may occur due to several methodological limitations. Copyright © 2012 Elsevier B.V. All rights reserved.

  11. Effectiveness of reactive oral cholera vaccination in rural Haiti: a case-control study

    PubMed Central

    Ivers, Louise C; Hilaire, Isabelle J; Teng, Jessica E; Almazor, Charles P; Jerome, J Gregory; Ternier, Ralph; Boncy, Jacques; Buteau, Josiane; Murray, Megan B; Harris, Jason B; Franke, Molly F

    2015-01-01

    Background Between April and June 2012, a reactive cholera vaccination campaign was conducted in Haiti using an oral inactivated bivalent whole-cell vaccine (BivWC). Methods We conducted a case-control study to estimate field effectiveness of the vaccine. Cases had acute watery diarrhea, sought treatment at one of three participating cholera treatment units from October 24, 2012 through March 9, 2014, and had a stool sample positive for cholera by culture. For each case, four controls (individuals who did not seek treatment for acute watery diarrhea) were matched by location of residence, calendar time, and age. We also conducted a bias-indicator case-control study to assess the likelihood of bias in the vaccine effectiveness (VE) study. Findings During the study period, 114 eligible individuals presented with acute watery diarrhea and were enrolled. 47 were analyzed as cases in the VE case-control study and 42 as cases in the bias-indicator study. In multivariable analyses, VE was 63% [95% confidence interval (CI): 8%–85%] by self-reported vaccination and 58% [95% CI: 13%–80%] for verified vaccination. Neither self-reported nor verified vaccination was significantly associated with non-cholera diarrhea (VE: 18% [95% CI: −208%–−78%] by self-report and −21% [95%CI: −238%–57%] for verified vaccination). Interpretation BivWC oral cholera vaccine was effective in protecting against cholera in Haiti during the study period –from 4 through 24 months after vaccination. Vaccination is an important component of epidemic cholera control efforts. Funding National Institutes of Health, Delivering Oral Vaccines Effectively project, Department of Global Health and Social Medicine at Harvard Medical School. PMID:25701994

  12. 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

  13. A case-control study of gastric cancer and diet in Italy.

    PubMed

    Buiatti, E; Palli, D; Decarli, A; Amadori, D; Avellini, C; Bianchi, S; Biserni, R; Cipriani, F; Cocco, P; Giacosa, A

    1989-10-15

    A case-control study was conducted in high- and low-risk areas of Italy to evaluate reasons for the striking geographic variation in gastric cancer (GC) mortality within the country. Personal interviews with 1,016 histologically confirmed GC cases and 1,159 population controls of similar age and sex revealed that the patients were more often of lower social class and resident in rural areas and more frequently reported a familial history of gastric (but not other) cancer. After adjusting for these effects, case-control differences were found for several dietary variables, assessed by asking about the usual frequency of consumption of 146 food items and beverages. A significant trend of increasing GC risk was found with increasing consumption of traditional soups, meat, salted/dried fish and a combination of cold cuts and seasoned cheeses. The habit of adding salt and the preference for salty foods were associated with elevated GC risk, while more frequently storing foods in the refrigerator, the availability of a freezer and use of frozen foods lowered risk. Reduced GC risk were associated with increasing intake of raw vegetables, fresh fruit and citrus fruits. Lowered risk was also related to consumption of spices, olive oil and garlic. Neither cigarette smoking nor alcoholic beverage drinking were significantly related to GC risk. The case-control differences tended to be consistent across geographic areas, despite marked regional variations in intake levels of certain foods. The high-risk areas tended to show higher consumption of food associated with elevated risk (traditional soups, cold cuts) and lower consumption of foods associated with reduced risks (raw vegetables, citrus fruits, garlic). Our findings indicate that dietary factors contribute to the regional variation of stomach cancer occurrence in Italy, and offer clues for further etiologic and prevention research.

  14. Exposure to electromagnetic fields and suicide among electric utility workers: a nested case-control study

    PubMed Central

    van Wijngaarden, E.; Savitz, D.; Kleckner, R.; Cai, J.; Loomis, D.

    2000-01-01

    OBJECTIVES—This nested case-control study examines mortality from suicide in relation to estimated exposure to extremely low frequency electromagnetic fields (EMFs) in a cohort of 138 905 male electric utility workers.
METHODS—Case-control sampling included 536 deaths from suicide and 5348 eligible controls. Exposure was classified based on work in the most common jobs with increased exposure to magnetic fields and indices of cumulative exposure to magnetic fields based on a measurement survey.
RESULTS—Suicide mortality was increased relative to work in exposed jobs and with indices of exposure to magnetic fields. Increased odds ratios (ORs) were found for years of employment as an electrician (OR 2.18; 95% confidence interval (95% CI) 1.25 to 3.80) or lineman (OR 1.59; 95% CI 1.18 to 2.14), whereas a decreased OR was found for power plant operators (OR 0.67; 95% CI 0.33 to 1.40). A dose response gradient with exposure to magnetic fields was found for exposure in the previous year, with a mortality OR of 1.70 (95% CI 1.00 to 2.90) in the highest exposure category. Stronger associations, with ORs in the range of 2.12-3.62, were found for men <50 years of age.
CONCLUSION—These data provide evidence for an association between occupational electromagnetic fields and suicide that warrants further evaluation. A plausible mechanism related to melatonin and depression provides a direction for additional laboratory research as well as epidemiological evaluation.


Keywords: electromagnetic fields; suicide; nested case-control PMID:10810112

  15. Parental smoking and childhood asthma: longitudinal and case-control studies

    PubMed Central

    Strachan, D.; Cook, D.

    1998-01-01

    BACKGROUND—The relation of parental smoking to wheezing and asthma occurring after the first year of life was assessed by a systematic quantitative review of case-control and longitudinal studies, complementing earlier reviews of cross sectional surveys and wheezing in early childhood.
METHODS—Fifty one relevant publications were identified after consideration of 1593 abstracts selected by electronic search of the Embase and Medline databases using keywords relevant to passive smoking in children. The search was completed in April 1997 and identified six studies of asthma incidence, seven of prognosis, 22 case-control studies, and 10 case series addressing disease severity.
RESULTS—Maternal smoking was associated with an increased incidence of wheezing illness up to age 6 (pooled odds ratio 1.31, 95% CI 1.22 to 1.41), but less strongly thereafter (1.13, 95% CI 1.04to 1.22). The long term prognosis of early wheezing illness was better if the mother smoked. The pooled odds ratio for asthma prevalence from 14 case-control studies was 1.37 (95% CI 1.15to 1.64) if either parent smoked. Four studies suggest that parental smoking is more strongly associated with wheezing among non-atopic children. Indicators of disease severity including symptom scores, attack frequency, medication use, hospital attendance, and life threatening bronchospasm were in general positively related to household smoke exposure.
CONCLUSIONS—The excess incidence of wheezing in smoking households appears to be largely non-atopic "wheezy bronchitis" with a relatively benign prognosis, but among children with established asthma, parental smoking is associated with more severe disease. This apparent paradox may be reconciled if environmental tobacco smoke is considered a co-factor provoking wheezing attacks, rather than a cause of the underlying asthmatic tendency.

 PMID:9659358

  16. ATRIUM: testing untyped SNPs in case-control association studies with related individuals.

    PubMed

    Wang, Zuoheng; McPeek, Mary Sara

    2009-11-01

    In genome-wide association studies, only a subset of all genomic variants are typed by current, high-throughput, SNP-genotyping platforms. However, many of the untyped variants can be well predicted from typed variants, with linkage disequilibrium (LD) information among typed and untyped variants available from an external reference panel such as HapMap. Incorporation of such external information can allow one to perform tests of association between untyped variants and phenotype, thereby making more efficient use of the available genotype data. When related individuals are included in case-control samples, the dependence among their genotypes must be properly addressed for valid association testing. In the context of testing untyped variants, an additional analytical challenge is that the dependence, across related individuals, of the partial information on untyped-SNP genotypes must also be assessed and incorporated into the analysis for valid inference. We address this challenge with ATRIUM, a method for case-control association testing with untyped SNPs, based on genome screen data in samples in which some individuals are related. ATRIUM uses LD information from an external reference panel to specify a one-degree-of-freedom test of association with an untyped SNP. It properly accounts for dependence in the partial information on untyped-SNP genotypes across related individuals. We demonstrate that ATRIUM is robust in that it maintains the nominal type I error rate even when the external reference panel is not well matched to the case-control sample. We apply the method to detect association between type 2 diabetes and variants on chromosome 10 in the Framingham SHARe data.

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

    PubMed

    Jacquez, Geoffrey M; Meliker, Jaymie R; Avruskin, Gillian A; Goovaerts, Pierre; Kaufmann, Andy; Wilson, Mark L; Nriagu, Jerome

    2006-08-03

    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. 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. 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 study design.

  18. Three ADIPOR1 Polymorphisms and Cancer Risk: A Meta-Analysis of Case-Control Studies.

    PubMed

    Ye, Jiaxiang; Jiang, Li; Wu, Changliang; Liu, Aiqun; Mao, Sufei; Ge, Lianying

    2015-01-01

    Studies have come to conflicting conclusions about whether polymorphisms in the adiponectin receptor 1 gene (ADIPOR1) are associated with cancer risk. To help resolve this question, we meta-analyzed case-control studies in the literature. PubMed, EMBASE, Cochrane Library, the Chinese Biological Medical Database and the Chinese National Knowledge Infrastructure Database were systematically searched to identify all case-control studies published through February 2015 examining any ADIPOR1 polymorphisms and risk of any type of cancer. Pooled odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were calculated. A total of 13 case-control studies involving 5,750 cases and 6,762 controls were analyzed. Analysis of the entire study population revealed a significant association between rs1342387(G/A) and overall cancer risk using a homozygous model (OR 0.82, 95%CI 0.72 to 0.94), heterozygous model (OR 0.84, 95%CI 0.76 to 0.93), dominant model (OR 0.85, 95%CI 0.75 to 0.97) and allele contrast model (OR 0.88, 95%CI 0.80 to 0.97). However, subgroup analysis showed that this association was significant only for Asians in the case of colorectal cancer. No significant associations were found between rs12733285(C/T) or rs7539542(C/G) and cancer risk, either in analyses of the entire study population or in analyses of subgroups. Our meta-analysis suggests that the ADIPOR1 rs1342387(G/A) polymorphism, but not rs12733285(C/T) or rs7539542(C/G), may be associated with cancer risk, especially risk of colorectal cancer in Asians. Large, well-designed studies are needed to verify our findings.

  19. Performance of Disease Risk Score Matching in Nested Case-Control Studies: A Simulation Study.

    PubMed

    Desai, Rishi J; Glynn, Robert J; Wang, Shirley; Gagne, Joshua J

    2016-05-15

    In a case-control study, matching on a disease risk score (DRS), which includes many confounders, should theoretically result in greater precision than matching on only a few confounders; however, this has not been investigated. We simulated 1,000 hypothetical cohorts with a binary exposure, a time-to-event outcome, and 13 covariates. Each cohort comprised 2 subcohorts of 10,000 patients each: a historical subcohort and a concurrent subcohort. DRS were estimated in the historical subcohorts and applied to the concurrent subcohorts. Nested case-control studies were conducted in the concurrent subcohorts using incidence density sampling with 2 strategies-matching on age and sex, with adjustment for additional confounders, and matching on DRS-followed by conditional logistic regression for 9 outcome-exposure incidence scenarios. In all scenarios, DRS matching yielded lower average standard errors and mean squared errors than did matching on age and sex. In 6 scenarios, DRS matching also resulted in greater empirical power. DRS matching resulted in less relative bias than did matching on age and sex at lower outcome incidences but more relative bias at higher incidences. Post-hoc analysis revealed that the effect of DRS model misspecification might be more pronounced at higher outcome incidences, resulting in higher relative bias. These results suggest that DRS matching might increase the statistical efficiency of case-control studies, particularly when the outcome is rare. © The Author 2016. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  20. An alternative experimental case-control design for genetic association studies on bovine mastitis.

    PubMed

    Biffani, S; Del Corvo, M; Capoferri, R; Pedretti, A; Luini, M; Williams, J L; Pagnacco, G; Minvielle, F; Minozzi, G

    2017-04-01

    The possibility of using genetic control strategies to increase disease resistance to infectious diseases relies on the identification of markers to include in the breeding plans. Possible incomplete exposure of mastitis-free (control) animals, however, is a major issue to find relevant markers in genetic association studies for infectious diseases. Usually, designs based on elite dairy sires are used in association studies, but an epidemiological case-control strategy, based on cows repeatedly field-tested could be an alternative for disease traits. To test this hypothesis, genetic association results obtained in the present work from a cohort of Italian Holstein cows tested for mastitis over time were compared with those from a previous genome-wide scan on Italian Holstein sires genotyped with 50k single nucleotide polymorphisms for de-regressed estimated breeding values for somatic cell counts (SCCs) on Bos taurus autosome (BTA6) and BTA14. A total of 1121 cows were selected for the case-control approach (cases=550, controls=571), on a combination of herd level of SCC incidence and of within herd individual level of SCC. The association study was conducted on nine previously identified markers, six on BTA6 and four on BTA14, using the R statistical environment with the 'qtscore' function of the GenABEL package, on high/low adjusted linear score as a binomial trait. The results obtained in the cow cohort selected on epidemiological information were in agreement with those obtained from the previous sire genome-wide association study (GWAS). Six out of the nine markers showed significant association, four on BTA14 (rs109146371, rs109234250, rs109421300, rs109162116) and two on BTA6 (rs110527224 and rs42766480). Most importantly, using mastitis as a case study, the current work further validated the alternative use of historical field disease data in case-control designs for genetic analysis of infectious diseases in livestock.

  1. Case-control study of the risk factors for age related macular degeneration

    PubMed Central

    Chaine, G.; Hullo, A.; Sahel, J.; Soubrane, G.; Espinasse-Berrod, M.; Schutz, D.; Bourguignon, C.; Harpey, C.; Brault, Y.; Coste, M.; Moccatti, D.; Bourgeois, H.

    1998-01-01

    AIM—A case-control study was initiated to determine the risk factors for the development of age related macular degeneration (AMD).
METHODS—Study participants, who were all white, aged 50-85 years, and were recruited from private ophthalmology practices. Each practitioner enrolled patients with bilateral AMD, who were then matched with controls for sex and age. Environmental factors and systemic and ocular histories were screened. All patients had bilateral red-free fundus photographs and fluorescein angiography. Photographs were classified into pigment epithelium alterations, drusen, geographic atrophy, and exudative AMD. Statistical analysis included the identification of risk factors for AMD. A multivariate analysis was performed at the end of the study. Analysis included the entire study population and was carried out for each stage of AMD.
RESULTS—1844 controls were compared with 1844 patients with AMD. Mean age was 71 years for controls and 72 for cases. Logistic regression identified six major risk factors for AMD (whole population): arterial hypertension (odds ratio (OR) =1.28), coronary disease (OR=1.31), hyperopia (OR=1.33), light coloured irises (OR=1.22), and lens opacities or previous cataract surgery (OR=1.55). The significance of vascular risk factors was increased for late stages of AMD, especially the atrophic forms (coronary disease, OR=3.19).
CONCLUSIONS—This large case-control study confirms some of the risk factors previously identified and may contribute to the determination of methods for prevention of AMD.

 Keywords: age related macular degeneration; risk factors; case-control study PMID:9893587

  2. Lung cancer risk among bricklayers in a pooled analysis of case-control studies.

    PubMed

    Consonni, Dario; De Matteis, Sara; Pesatori, Angela C; Bertazzi, Pier Alberto; Olsson, Ann C; Kromhout, Hans; Peters, Susan; Vermeulen, Roel C H; Pesch, Beate; Brüning, Thomas; Kendzia, Benjamin; Behrens, Thomas; Stücker, Isabelle; Guida, Florence; Wichmann, Heinz-Erich; Brüske, Irene; Landi, Maria Teresa; Caporaso, Neil E; Gustavsson, Per; Plato, Nils; Tse, Lap Ah; Yu, Ignatius Tak-Sun; Jöckel, Karl-Heinz; Ahrens, Wolfgang; Pohlabeln, Hermann; Merletti, Franco; Richiardi, Lorenzo; Simonato, Lorenzo; Forastiere, Francesco; Siemiatycki, Jack; Parent, Marie-Élise; Tardón, Adonina; Boffetta, Paolo; Zaridze, David; Chen, Ying; Field, John K; 't Mannetje, Andrea; Pearce, Neil; McLaughlin, John; Demers, Paul; Lissowska, Jolanta; Szeszenia-Dabrowska, Neonila; Bencko, Vladimir; Foretova, Lenka; Janout, Vladimir; Rudnai, Peter; Fabiánová, Eleonóra; Stanescu Dumitru, Rodica; Bueno-de-Mesquita, H Bas; Schüz, Joachim; Straif, Kurt

    2015-01-15

    Bricklayers may be exposed to several lung carcinogens, including crystalline silica and asbestos. Previous studies that analyzed lung cancer risk among these workers had several study design limitations. We examined lung cancer risk among bricklayers within SYNERGY, a large international pooled analysis of case-control studies on lung cancer and the joint effects of occupational carcinogens. For men ever employed as bricklayers we estimated odds ratios (OR) and 95% confidence intervals (CI) adjusted for study center, age, lifetime smoking history and employment in occupations with exposures to known or suspected lung carcinogens. Among 15,608 cases and 18,531 controls, there were 695 cases and 469 controls who had ever worked as bricklayers (OR: 1.47; 95% CI: 1.28-1.68). In studies using population controls the OR was 1.55 (95% CI: 1.32-1.81, 540/349 cases/controls), while it was 1.24 (95% CI: 0.93-1.64, 155/120 cases/controls) in hospital-based studies. There was a clear positive trend with length of employment (p < 0.001). The relative risk was higher for squamous (OR: 1.68, 95% CI: 1.42-1.98, 309 cases) and small cell carcinomas (OR: 1.78, 95% CI: 1.44-2.20, 140 cases), than for adenocarcinoma (OR: 1.17, 95% CI: 0.95-1.43, 150 cases) (p-homogeneity: 0.0007). ORs were still elevated after additional adjustment for education and in analyses using blue collar workers as referents. This study provided robust evidence of increased lung cancer risk in bricklayers. Although non-causal explanations cannot be completely ruled out, the association is plausible in view of the potential for exposure to several carcinogens, notably crystalline silica and to a lesser extent asbestos. © 2014 UICC.

  3. 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.

  4. Challenges in Recruiting Aging Women Holocaust Survivors to a Case Control Study of Breast Cancer.

    PubMed

    Vin-Raviv, Neomi; Dekel, Rachel; Barchana, Micha; Linn, Shai; Keinan-Boker, Lital

    2015-01-01

    Older adults are underrepresented in medical research for many reasons, including recruitment difficulties. Recruitment of older adults for research studies is often a time-consuming process and can be more challenging when the study involves older adults with unique exposures to traumatic events and from minority groups. The current article provides a brief overview of (a) challenges encountered while recruiting aging women Holocaust survivors for a case control study and (b) strategies used for meeting those challenges. The case group comprised women Holocaust survivors who were recently diagnosed with breast cancer and the control group comprised healthy women from a Holocaust-survivor community in Israel.

  5. Consumption of dairy produce and alcohol in a case-control study of breast cancer.

    PubMed

    Lê, M G; Moulton, L H; Hill, C; Kramar, A

    1986-09-01

    In a French case-control study of 1,010 breast cancer cases and 1,950 controls with nonmalignant diseases, the risk of breast cancer was found to be positively associated with frequency of cheese consumption and the level of fat in the milk consumed. A negative association was found between frequency of yogurt consumption and the risk of breast cancer. No association was found between the consumption of butter and the risk of breast cancer. The positive association between a daily consumption of alcohol and the risk of breast cancer previously reported was not altered when dairy produce consumption was taken into account.

  6. Risk factors for femicide-suicide in abusive relationships: results from a multisite case control study.

    PubMed

    Koziol-McLain, Jane; Webster, Daniel; McFarlane, Judith; Block, Carolyn Rebecca; Ulrich, Yvonne; Glass, Nancy; Campbell, Jacquelyn C

    2006-02-01

    The killing of women by men who then take their own lives (femicide-suicide) is the most common form of homicide-suicide. This study identified femicide-suicide risk factors in an 11-city case-control study of femicide in the United States. Perpetrator, victim, relationship, and incident characteristics were analyzed for femicide-suicide cases (n = 67) and controls (n = 356, women living in the community with nonfatal physical abuse) using logistic regression modeling. Two risk factors emerged that were unique to femicide-suicides cases compared to overall femicide risk analyses: prior perpetrator suicide threats and victims having ever been married to the perpetrator.

  7. [Recurrent myocardial infarctions: specific changes in biomarkers and in myocardial remodeling (case-control study)].

    PubMed

    Volkova, E G; Malykhina, O P; Levashov, S Iu

    2007-01-01

    Basing on a case-control study (n=81) with the use of standard methods of myocardial infarction verification, examination of hemogram, troponin T, C-reactive protein, echocardiography data it was established that markers of myocardial infarction (troponin T level) and inflammation (C reactive protein level, lymphopenia) during recurrent infarctions are less pronounced than during first infarctions. Remodeling in recurrent infarctions had the following specific characteristics: increase of left ventricular end diastolic dimension, myocardial mass index, diastolic dysfunction and stroke volume with unchanged ejection fraction.

  8. Preeclampsia and preterm delivery: A population-based case-control study.

    PubMed

    Davies, Emma L; Bell, Jacqueline S; Bhattacharya, Sohinee

    2016-11-01

    To determine the contribution of preeclampsia toward preterm birth in primiparous women. This large population-based case-control study used the Aberdeen Maternity and Neonatal Databank to analyze data on primiparous women with singleton pregnancies, who delivered between 1997 and 2012. A significant positive association was found between preeclampsia and preterm birth (adjusted odds ratio 4.43; 95% confidence interval 3.80-5.16). Magnitude of association varied according to the onset of delivery and year of delivery. Preeclampsia is an important contributor to preterm delivery in this setting and therefore a potentially useful condition to target in order to reduce preterm rates.

  9. Comparison of racial differences in childhood cancer risk in case-control studies and population-based cancer registries.

    PubMed

    Slusky, Danna A; Mezei, Gabor; Metayer, Catherine; Selvin, Steve; Von Behren, Julie; Buffler, Patricia A

    2012-02-01

    Although selection bias in case-control studies has been studied extensively, little is known about selection of cases and controls among various ethnic groups. This study compares racial differences in childhood cancer rates as estimated by case-control studies with various design features. It also compares estimates of racial distribution among cases as reported by case-control studies to those observed for an ideal case series with complete ascertainment of cases for these studies or in population-based cancer registries in corresponding geographic regions and calendar periods. Peer-reviewed publications on childhood leukemia and brain tumors from North America, published between 1980 and 2007, were reviewed. Incidence data by race/ethnicity were compiled from research publications, federal cancer statistics, and cancer registries. Meta-analysis was conducted to assess racial/ethnic differences by study characteristics. Racial distributions of cases from published case-control studies were compared to those of a presumably noncensored case distribution (i.e. include both participating and non-participating cases in a case-control study) or cases recorded by cancer registries. In interview-based case-control studies of childhood cancer, the proportion of Whites compared to non-Whites tended to be higher among controls than among cases; however, the opposite was true for record-based case-control studies. Additionally, the proportion of Whites tended to be higher among the participating cases in the published case-control studies compared to the proportion of Whites among the non-participating cases or in cancer registries. Investigators need to consider differential participation by racial group as a potential source of bias in the interpretation of case-control study results. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. Brazilian multicenter study on prevalence of preterm birth and associated factors

    PubMed Central

    2010-01-01

    Background The occurrence of preterm birth remains a complex public health condition. It is considered the main cause of neonatal morbidity and mortality, resulting in a high likelihood of sequelae in surviving children. With variable incidence in several countries, it has grown markedly in the last decades. In Brazil, however, there are still difficulties to estimate its real occurrence. Therefore, it is essential to establish the prevalence and causes of this condition in order to propose prevention actions. This study intend to collect information from hospitals nationwide on the prevalence of preterm births, their associated socioeconomic and environmental factors, diagnostic and treatment methods resulting from causes such as spontaneous preterm labor, prelabor rupture of membranes, and therapeutic preterm birth, as well as neonatal results. Methods/Design This proposal is a multicenter cross-sectional study plus a nested case-control study, to be implemented in 27 reference obstetric centers in several regions of Brazil (North: 1; Northeast: 10; Central-west: 1; Southeast: 13; South: 2). For the cross sectional component, the participating centers should perform, during a period of six months, a prospective surveillance of all patients hospitalized to give birth, in order to identify preterm birth cases and their main causes. In the first three months of the study, an analysis of the factors associated with preterm birth will also be carried out, comparing women who have preterm birth with those who deliver at term. For the prevalence study, 37,000 births will be evaluated (at term and preterm), corresponding to approximately half the deliveries of all participating centers in 12 months. For the case-control study component, the estimated sample size is 1,055 women in each group (cases and controls). The total number of preterm births estimated to be followed in both components of the study is around 3,600. Data will be collected through a questionnaire all

  11. Hyperactivity of the default-mode network in first-episode, drug-naive schizophrenia at rest revealed by family-based case-control and traditional case-control designs.

    PubMed

    Guo, Wenbin; Liu, Feng; Chen, Jindong; Wu, Renrong; Li, Lehua; Zhang, Zhikun; Chen, Huafu; Zhao, Jingping

    2017-03-01

    Abnormal regional activity and functional connectivity of the default-mode network (DMN) have been reported in schizophrenia. However, previous studies may have been biased by unmatched case-control design. To limit such bias, the present study used both the family-based case-control design and the traditional case-control design to investigate abnormal regional activity of the DMN in patients with schizophrenia at rest.Twenty-eight first-episode, drug-naive patients with schizophrenia, 28 age-, sex-matched unaffected siblings of the patients (family-based controls, FBC), and 40 healthy controls (HC) underwent resting-state functional magnetic resonance imaging (fMRI) scans. The group-independent component analysis and fractional amplitude of low-frequency fluctuation (fALFF) methods were used to analyze the data.Patients with schizophrenia show increased fALFF in an overlapped region of the right superior medial prefrontal cortex (MPFC) relative to the FBC and the HC. Compared with the HC, the patients and the FBC exhibit increased fALFF in an overlapped region of the left posterior cingulate cortex/precuneus (PCC/PCu). Furthermore, the z values of the 2 overlapped regions can separate the patients from the FBC/HC, and separate the patients/FBC from the HC with relatively high sensitivity and specificity.Both the family-based case-control and traditional case-control designs reveal hyperactivity of the DMN in first-episode, drug-naive patients with paranoid schizophrenia, which highlights the importance of the DMN in the neurobiology of schizophrenia. Family-based case-control design can limit the confounding effects of environmental factors in schizophrenia. Combination of the family-based case-control and traditional case-control designs may be a viable option for the neuroimaging studies.

  12. [Effects of tobramycin dexamethasone eye ointment for blepharitis: multi-center clinical trial].

    PubMed

    Yan, Xiao-ming; Sun, Xu-guang; Xie, Han-ping; Hong, Jing; Wang, Zhi-cong

    2013-01-01

    To realize the effectiveness and security of Tobramycin and Dexamethasone Eye Ointment for blepharitis treatment. Design Case control studies. Participants 148 patients be diagnosed as blepharitis including 81 cases as research group and 67 cases as control group. Multi-center randomized controlled clinical trial. The patients met the inclusion criteria from First Hospital Peking University, Beijing Tongren Hospital, Southwest Hospital, Ophthalmology Center Zhongshan University and Third Hospital Peking University were divided into two groups in Aug. to Dec. 2011. Tobramycin dexamethasone eye ointment was applied to eye lid in research group while patients in control group used tobramycin eye ointment. All patients were informed to apply warm compress to the lids, mechanically washing to the eyelids and artificial tears. At the beginning, the 7(th) day, the 14(th) day and the 28(th) day of treatment, observation of symptom, sign and side effect were recorded. Before treatment the difference of the symptom scores of burning sensation, tears, photophobia and itch of two groups has no statistically significant (t = 1.87, 0.43, -0.64, 0.93, P > 0.05), but the symptom scores have a statistically significant decrease (t = 1.99 - 6.90, P < 0.05) at the 7(th) day, 14(th) day, 28(th) day. Before treatment the difference of signs scores have no statistically significant except the term of new blood vessels (t = 2.32, P = 0.02) while all the signs scores have a statistically significant decrease at the 7(th) day, 14(th) day, 28(th) day. Side effect: the number of patients with elevated intraocular pressure of research and control group is 3 and 1 respectively and the ratio is 3.7% and 1.5%. The tobramycin dexamethasone eye ointment can improve signs and symptoms of blepharitis patients. Some patients have to face with the risk of elevated intraocular pressure and it's necessary to monitor the intraocular pressure.

  13. Association of Fetal Abdominal-Head Circumference Size Difference With Shoulder Dystocia: A Multicenter Study.

    PubMed

    Endres, Loraine; DeFranco, Emily; Conyac, Theresa; Adams, Marci; Zhou, Ying; Magner, Kristin; O'Rourke, Luke; Bernhard, Kiley A; Siddiqui, Danish; McCormick, Anna; Abramowicz, Jacques; Merkel, Ronald; Jawish, Rana; Habli, Mounira; Floman, Alissa; Magann, Everett F; Chauhan, Suneet P

    2015-10-01

    Objective This study aims to determine if shoulder dystocia is associated with a difference in the fetal abdominal (AC) to head circumference (HC) of 50 mm or more noted on antenatal ultrasound. Study Design A multicenter matched case-control study was performed comparing women who had shoulder dystocia to controls who did not. Women with vaginal births of live born nonanomalous singletons ≥ 36 weeks of gestation with an antenatal ultrasound within 4 weeks of delivery were included. Controls were matched for gestational age, route of delivery, and diabetes status. Results We identified 181 matched pairs. Only 5% of the fetuses had an AC to HC of ≥ 50 mm. The proportion of AC to HC difference of ≥ 50 mm was significantly higher in shoulder dystocia cases (8%) than controls (1%, p = 0.002). With multivariate regression, the three significant factors associated with shoulder dystocia were AC to HC ≥ 50 mm (odds ratio [OR], 7.3; confidence interval [CI], 1.6-33.3; p = 0.010), femur length (OR, 1.1; CI, 1.0-1.2; p = 0.002), and induced labor (OR, 1.8; CI, 1.1-3.1; p = 0.027). Conclusion A prenatal ultrasound finding of a difference in AC to HC of ≥ 50 mm while uncommon is associated with shoulder dystocia.

  14. Pilot age and geographic region of commuter and air taxi crashes: a case-control study.

    PubMed

    Rebok, George W; Qiang, Yandong; Baker, Susan P; Li, Guohua

    2011-02-01

    Previous studies of major airline and general aviation crashes have identified a host of risk factors. We examined risk factors related to crashes involving commuter air carrier and air taxi flights. A matched case-control design was applied to assess the association of pilot age, total flight time, and geographic region with commuter air carrier and air taxi crashes (14 CFR Part 135) from 1983-2002 in the United States. A total of 2033 commuter air carrier or air taxi crashes from the National Transportation Safety Board aviation crash database were identified as eligible cases. Controls were randomly selected incidents from the Federal Aviation Administration's (FAA) aviation incident database coded under Part 135 operation. Relative to controls, commuter air carrier and air taxi crashes were less likely to occur in pilots under 30 yr of age (adjusted odds ratio 0.68, 95% confidence interval 0.54-0.88) after adjusting for geographic region and total flight time. With adjustment for pilot age and total flight time, the commuter air carrier and air taxi crashes with pilot error were nearly 13 times as likely to be in Alaska as their matched controls (adjusted odds ratio 12.84, 95% confidence interval 5.24-31.45). These results suggest that pilot age may be associated with risk of crash involvement in Part 135 operations. The excess crash risk in Alaska with or without pilot error underscores the importance of environmental hazards in flight safety.

  15. Results of case-control studies support the association between contact lens use and Acanthamoeba keratitis.

    PubMed

    Pacella, Elena; La Torre, Giuseppe; De Giusti, Maria; Brillante, Chiara; Lombardi, Anna Maria; Smaldone, Gianpaolo; Lenzi, Tommaso; Pacella, Fernanda

    2013-01-01

    Acanthamoeba keratitis (AK) is ever more frequently reported in industrialized countries. The loss of the corneal surface integrity consequent to secondary microtrauma produced by the use of contact lens (CL) favors the penetration of the parasite into the corneal tissue. A scientific review was performed to investigate the association of CL wear as an Acanthamoeba keratitis (AK) risk factor. A computerized screening of 7834 Medline articles (4623 from PubMed; 3211 from Scopus) used a strict selection criteria of case-control studies involving CL wear and/or trauma. The search yielded five case-control studies published from 1995 to 2012. All studies included showed a statistically significant positive association between AK and CL use, with a combined odds ratio (OR) of 10.21 (95%, confidence intervals [CI]; 3.57-27.64). All studies included showed a statistically significant positive association between AK and CL use, though with differing OR values. Though rare, AK should be held in higher consideration when ophthalmologists are faced with CL users exhibiting simplex-like lesions associated with circular stromal infiltrates and disproportionate ocular pain in respect to the objective clinical picture.

  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. Vitamin D and pancreatic cancer: a pooled analysis from the Pancreatic Cancer Case-Control Consortium.

    PubMed

    Waterhouse, M; Risch, H A; Bosetti, C; Anderson, K E; Petersen, G M; Bamlet, W R; Cotterchio, M; Cleary, S P; Ibiebele, T I; La Vecchia, C; Skinner, H G; Strayer, L; Bracci, P M; Maisonneuve, P; Bueno-de-Mesquita, H B; Zaton Ski, W; Lu, L; Yu, H; Janik-Koncewicz, K; Polesel, J; Serraino, D; Neale, R E

    2015-08-01

    The potential role of vitamin D in the aetiology of pancreatic cancer is unclear, with recent studies suggesting both positive and negative associations. We used data from nine case-control studies from the International Pancreatic Cancer Case-Control Consortium (PanC4) to examine associations between pancreatic cancer risk and dietary vitamin D intake. Study-specific odds ratios (ORs) were estimated using multivariable logistic regression, and ORs were then pooled using a random-effects model. From a subset of four studies, we also calculated pooled estimates of association for supplementary and total vitamin D intake. Risk of pancreatic cancer increased with dietary intake of vitamin D [per 100 international units (IU)/day: OR = 1.13, 95% confidence interval (CI) 1.07-1.19, P = 7.4 × 10(-6), P-heterogeneity = 0.52; ≥230 versus <110 IU/day: OR = 1.31, 95% CI 1.10-1.55, P = 2.4 × 10(-3), P-heterogeneity = 0.81], with the association possibly stronger in people with low retinol/vitamin A intake. Increased risk of pancreatic cancer was observed with higher levels of dietary vitamin D intake. Additional studies are required to determine whether or not our finding has a causal basis. © The Author 2015. Published by Oxford University Press on behalf of the European Society for Medical Oncology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  18. A case--control study of selenium in nails and prostate cancer risk in British men.

    PubMed

    Allen, N E; Morris, J S; Ngwenyama, R A; Key, T J

    2004-04-05

    In view of the experimental evidence suggesting that the micronutrient selenium reduces prostate cancer risk, we investigated the association between the selenium level in fingernails, a measure of long-term selenium intake, and prostate cancer risk in a case-control study among 656 British men, conducted in 1989-1992. Nail clippings were taken at the time of recruitment and selenium concentration, measured using neutron activation techniques, was successfully assayed for 300 case-control pairs and varied six-fold among the controls (0.59 p.p.m.; interquartile range, 0.50-0.71 p.p.m.). Nail selenium concentration was not significantly associated with prostate cancer risk: men in the highest quartile of nail selenium had a slightly increased risk compared with men in the lowest quartile (OR 1.24, 95 CI, 0.73-2.10); for advanced prostate cancer, men in the highest quartile had a slightly reduced risk compared with men in the lowest quartile (OR 0.78, 95% CI, 0.27-2.25). These results suggest that selenium is not strongly associated with prostate cancer risk in British men.

  19. 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.

  20. A Case-Control Study of Risk Factors for Salivary Gland Cancer in Canada

    PubMed Central

    de Groh, Margaret; Morrison, Howard

    2017-01-01

    Aim. To assess the effect of various lifestyle risk factors on the risk of salivary gland cancer in Canada using data from a population-based case-control study. Methods. Data from a population-based case-control study of 132 incident cases of salivary gland cancer and 3076 population controls were collected through self-administered questionnaire and analysed using unconditional logistic regression. Results. Four or more servings/week of processed meat product was associated with an adjusted odds ratio (OR) and corresponding 95% confidence interval (CI) of 1.62 (1.02–2.58). Nonsignificantly increased ORs were also related to obesity, >7 drinks/week of alcohol consumption, and occupational exposure to radiation. Furthermore, nonsignificantly decreased ORs were found to be associated with high education level (>12 years) (OR = 0.65), high consumption of spinach/squash (OR = 0.62) and all vegetables/vegetable juices (OR = 0.75), and >30 sessions/month of recreational physical activity (OR = 0.78). Conclusions. This study suggests positive associations with consumption of processed meat, smoking, obesity, alcohol drinking, and occupational exposure to radiation as well as negative associations with higher education, consumption of spinach/squash, and physical activity, which suggest a role of lifestyle factors in the etiology of salivary gland cancer. However, these findings were based on small number of cases and were nonsignificant. Further larger studies are warranted to confirm our findings. PMID:28133481

  1. 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.

  2. 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.

  3. [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.

  4. Chernobyl-related thyroid cancer in children of Belarus: a case-control study.

    PubMed

    Astakhova, L N; Anspaugh, L R; Beebe, G W; Bouville, A; Drozdovitch, V V; Garber, V; Gavrilin, Y I; Khrouch, V T; Kuvshinnikov, A V; Kuzmenkov, Y N; Minenko, V P; Moschik, K V; Nalivko, A S; Robbins, J; Shemiakina, E V; Shinkarev, S; Tochitskaya, S I; Waclawiw, M A

    1998-09-01

    The accident at the Chernobyl nuclear power plant on April 26, 1986, released approximately 2 EBq of 131I and other radioiodine isotopes that heavily contaminated southern Belarus. An increase in thyroid cancer reported in 1992 and attributed to the Chernobyl accident was challenged as possibly the result of intensive screening. We began a case-control study to test the hypothesis that the Chernobyl accident caused the increase in thyroid cancer. Records of childhood thyroid cancer in the national therapy centers in Minsk in 1992 yielded 107 individuals with confirmed pathology diagnoses and available for interview. Pathways to diagnosis were (1) routine endocrinological screening in 63, (2) presentation with enlarged or nodular thyroid in 25 and (3) an incidental finding in 19. Two sets of controls were chosen, one matched on pathway to diagnosis, the other representing the area of heavy fallout, both matched on age, sex and rural/urban residence in 1986. The 131I dose to the thyroid was estimated from ground deposition of 137Cs, ground deposition of 131I, a data bank of 1986 thyroid radiation measurements, questionnaires and interviews. Highly significant differences were observed between cases and controls (both sets) with respect to dose. The differences persisted within pathway to diagnosis, gender, age and year of diagnosis, and level of iodine in the soil, and were most marked in the southern portion of the Gomel region. The case-control comparisons indicate a strong relationship between thyroid cancer and estimated radiation dose from the Chernobyl accident.

  5. Using sign score regression models to select variables in case-control studies.

    PubMed

    O'Gorman, T W

    1995-02-28

    This paper evaluates the performance of four variable selection methods suitable for case-control studies. Two of the methods are logistic regression and the rank transformed version of it which uses the ranks of the explanatory variables in place of the original observations. The third method is based on Kendall's tau b correlations. I propose a fourth method, a sign score regression model to select variables. To evaluate these four methods, I generate many data sets for a case group and a control group with the use of several different distributions and covariance matrices. I evaluate the methods on their ability to select correctly the variables related to case-control status while not selecting the unrelated variables. Using this criterion, the sign score regression method and the tau b method are more effective than the other two methods with uncorrelated or weakly correlated variables. The sign score regression method is more effective than the tau b method for all simulations that use normal variables and for some that use log-normal variables. Overall, the sign score regression method is the most effective variable selection method for data sets that have low or moderate correlations between variables.

  6. Anorexia nervosa versus bulimia nervosa: differences based on retrospective correlates in a case-control study.

    PubMed

    Machado, Bárbara C; Gonçalves, Sónia F; Martins, Carla; Brandão, Isabel; Roma-Torres, António; Hoek, Hans W; Machado, Paulo P

    2016-06-01

    This study is the result of two Portuguese case-control studies that examined the replication of retrospective correlates and preceding life events in anorexia nervosa (AN) and bulimia nervosa (BN) development. This study aims to identify retrospective correlates that distinguish AN and BN METHOD: A case-control design was used to compare a group of women who met Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria for AN (N = 98) and BN (N = 79) with healthy controls (N = 86) and with other psychiatric disorders (N = 68). Each control group was matched with AN patients regarding age and parental social categories. Risk factors were assessed by interviewing each person with the Oxford Risk Factor Interview. Compared to AN, women with BN reported significantly higher rates of paternal high expectations, excessive family importance placed on fitness/keeping in shape, and negative consequences due to adolescent overweight and adolescent objective overweight. Overweight during adolescence emerged as the most relevant retrospective correlate in the distinction between BN and AN participants. Family expectations and the importance placed on keeping in shape were also significant retrospective correlates in the BN group.

  7. Mendelian Randomization Studies for a Continuous Exposure Under Case-Control Sampling

    PubMed Central

    Dai, James Y.; Zhang, Xinyi Cindy

    2015-01-01

    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. PMID:25713335

  8. Diagnostic Microbiologic Methods in the GEMS-1 Case/Control Study

    PubMed Central

    Panchalingam, Sandra; Antonio, Martin; Hossain, Anowar; Mandomando, Inacio; Ochieng, Ben; Oundo, Joseph; Ramamurthy, T.; Tamboura, Boubou; Zaidi, Anita K. M.; Petri, William; Houpt, Eric; Murray, Patrick; Prado, Valeria; Vidal, Roberto; Steele, Duncan; Strockbine, Nancy; Sansonetti, Philippe; Glass, Roger I.; Robins-Browne, Roy M.; Tauschek, Marija; Svennerholm, Ann-Marie; Kotloff, Karen; Levine, Myron M.; Nataro, James P.

    2012-01-01

    To understand the etiology of moderate-to-severe diarrhea among children in high mortality areas of sub-Saharan Africa and South Asia, we performed a comprehensive case/control study of children aged <5 years at 7 sites. Each site employed an identical case/control study design and each utilized a uniform comprehensive set of microbiological assays to identify the likely bacterial, viral and protozoal etiologies. The selected assays effected a balanced consideration of cost, robustness and performance, and all assays were performed at the study sites. Identification of bacterial pathogens employed streamlined conventional bacteriologic biochemical and serological algorithms. Diarrheagenic Escherichia coli were identified by application of a multiplex polymerase chain reaction assay for enterotoxigenic, enteroaggregative, and enteropathogenic E. coli. Rotavirus, adenovirus, Entamoeba histolytica, Giardia enterica, and Cryptosporidium species were detected by commercially available enzyme immunoassays on stool samples. Samples positive for adenovirus were further evaluated for adenovirus serotypes 40 and 41. We developed a novel multiplex assay to detect norovirus (types 1 and 2), astrovirus, and sapovirus. The portfolio of diagnostic assays used in the GEMS study can be broadly applied in developing countries seeking robust cost-effective methods for enteric pathogen detection. PMID:23169941

  9. 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

  10. An incidence density sampling program for nested case-control analyses

    PubMed Central

    Richardson, D

    2004-01-01

    Methods: This paper presents a simple computer program for incidence density sampling. This program was evaluated using data derived from a cohort study of mortality among workers employed in the nuclear weapons industry. Controls were selected for cases via incidence density sampling; an estimate of the exposure-mortality association was obtained via conditional logistic regression. After 100 iterations of this procedure, the average effect estimate was compared to the risk estimate obtained via proportional hazards regression. The same methods were used to evaluate a program for incidence density sampling that was proposed previously by Pearce in 1989.5 Results: Relative risk estimates obtained from nested case-control analyses conducted using the incidence density sampling program reported in this paper are unbiased. In contrast, the program for incidence density sampling proposed by Pearce5 tended to produce biased relative risk estimates; the magnitude of bias increased with increasing numbers of controls selected per case. Conclusions: The computer program described in this paper offers a simple approach to incidence density sampling for nested case-control analyses with exact matching on attained age and appropriate enumeration of the pool of eligible controls for each case. This method overcomes problems of bias inherent in a previously proposed program for incidence density sampling. PMID:15550597

  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.

  12. Snippets From the Past: Is Flint, Michigan, the Birthplace of the Case-Control Study?

    PubMed Central

    Morabia, Alfredo

    2013-01-01

    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

  13. Rethinking sources of representative controls for the conduct of case-control studies in minority populations.

    PubMed

    Bandera, Elisa V; Chandran, Urmila; Zirpoli, Gary; McCann, Susan E; Ciupak, Gregory; Ambrosone, Christine B

    2013-05-31

    Recruitment of controls remains a challenge in case-control studies and particularly in studies involving minority populations. We compared characteristics of controls recruited through random digit dialing (RDD) to those of community controls enrolled through churches, health events and other outreach sources among women of African ancestry (AA) participating in the Women's Circle of Health Study, a case-control study of breast cancer. Odds ratios and 95% confidence intervals were also computed using unconditional logistic regression to evaluate the impact of including the community controls for selected variables relevant to breast cancer and for which there were significant differences in distribution between the two control groups. Compared to community controls (n=347), RDD controls (n=207) had more years of education and higher income, lower body mass index, were more likely to have private insurance, and less likely to be single. While the percentage of nulliparous women in the two groups was similar, community controls tended to have more children, have their first child at a younger age, and were less likely to breastfeed their children. Dietary intake was similar in the two groups. Compared to census data, the combination of RDD and community controls seems to be more representative of the general population than RDD controls alone. Furthermore, the inclusion of the community group had little impact on the magnitude of risk estimates for most variables, while enhancing statistical power. Community-based recruitment was found to be an efficient and feasible method to recruit AA controls.

  14. Bronchodilator treatment and asthma death: a new analysis of a British case-control study.

    PubMed

    Butland, Barbara K; Anderson, H Ross; Cates, Christopher J

    2011-04-01

    We investigated the relationship between asthma mortality and long-acting beta(2)-agonists (LABA), including interactions with age, inhaled corticosteroids (ICS) and social deprivation. We used a new, expanded dataset of recorded medication extracted blind from the anonymised primary care records of an earlier British case-control study. The cases were 532 asthma deaths aged < 65 occurring between 1994 and 1998 and the controls were 532 asthma admissions, matched for age, hospital, and index date (date of death/asthma admission). The exposure periods prior to the index date were current (≤ 2 months) or recent ( > 2-6 months). We found no evidence of an overall association with current (OR = 0.89 [95% confidence interval 0.61-1.30]) or recent (1.08 [0.76-1.53]) mention of LABA, but there was some evidence of a positive interaction with age. Among controls with mention of LABA, a concurrent mention of ICS (within 1 month) was common (85% and 93% for the two respective periods) which limited our power to investigate any interaction between LABA and ICS. There was no coherent evidence of effect modification by social deprivation. In a population based case-control study where prescription of LABA without concomitant ICS was uncommon there was no evidence of an overall association between LABA and asthma death.

  15. Association between bullous pemphigoid and neurologic diseases: a case-control study.

    PubMed

    Casas-de-la-Asunción, E; Ruano-Ruiz, J; Rodríguez-Martín, A M; Vélez García-Nieto, A; Moreno-Giménez, J C

    2014-11-01

    In the past 10 years, bullous pemphigoid has been associated with other comorbidities and neurologic and psychiatric conditions in particular. Case series, small case-control studies, and large population-based studies in different Asian populations, mainland Europe, and the United Kingdom have confirmed this association. However, no data are available for the Spanish population. This was an observational, retrospective, case-control study with 1:2 matching. Fifty-four patients with bullous pemphigoid were selected. We compared the percentage of patients in each group with concurrent neurologic conditions, ischemic heart disease, diabetes, chronic obstructive pulmonary disease, and solid tumors using univariate logistic regression. An association model was constructed with conditional multiple logistic regression. The case group had a significantly higher percentage of patients with cerebrovascular accident and/or transient ischemic attack (odds ratio [OR], 3.06; 95% CI, 1.19-7.87], dementia (OR, 5.52; 95% CI, 2.19-13.93), and Parkinson disease (OR, 5; 95% CI, 1.57-15.94). A significantly higher percentage of cases had neurologic conditions (OR, 6.34; 95% CI, 2.89-13.91). Dementia and Parkinson disease were independently associated with bullous pemphigoid in the multivariate analysis. Patients with bullous pemphigoid have a higher frequency of neurologic conditions. Copyright © 2013 Elsevier España, S.L.U. and AEDV. All rights reserved.

  16. Global, local and focused geographic clustering for case-control data with residential histories

    PubMed Central

    Jacquez, Geoffrey M; Kaufmann, Andy; Meliker, Jaymie; Goovaerts, Pierre; AvRuskin, Gillian; Nriagu, Jerome

    2005-01-01

    Background This paper introduces a new approach for evaluating clustering in case-control data that accounts for residential histories. Although many statistics have been proposed for assessing local, focused and global clustering in health outcomes, few, if any, exist for evaluating clusters when individuals are mobile. Methods Local, global and focused tests for residential histories are developed based on sets of matrices of nearest neighbor relationships that reflect the changing topology of cases and controls. Exposure traces are defined that account for the latency between exposure and disease manifestation, and that use exposure windows whose duration may vary. Several of the methods so derived are applied to evaluate clustering of residential histories in a case-control study of bladder cancer in south eastern Michigan. These data are still being collected and the analysis is conducted for demonstration purposes only. Results Statistically significant clustering of residential histories of cases was found but is likely due to delayed reporting of cases by one of the hospitals participating in the study. Conclusion Data with residential histories are preferable when causative exposures and disease latencies occur on a long enough time span that human mobility matters. To analyze such data, methods are needed that take residential histories into account. PMID:15784151

  17. Diagnostic microbiologic methods in the GEMS-1 case/control study.

    PubMed

    Panchalingam, Sandra; Antonio, Martin; Hossain, Anowar; Mandomando, Inacio; Ochieng, Ben; Oundo, Joseph; Ramamurthy, T; Tamboura, Boubou; Zaidi, Anita K M; Petri, William; Houpt, Eric; Murray, Patrick; Prado, Valeria; Vidal, Roberto; Steele, Duncan; Strockbine, Nancy; Sansonetti, Philippe; Glass, Roger I; Robins-Browne, Roy M; Tauschek, Marija; Svennerholm, Ann-Marie; Berkeley, Lynette Y; Kotloff, Karen; Levine, Myron M; Nataro, James P

    2012-12-01

    To understand the etiology of moderate-to-severe diarrhea among children in high mortality areas of sub-Saharan Africa and South Asia, we performed a comprehensive case/control study of children aged <5 years at 7 sites. Each site employed an identical case/control study design and each utilized a uniform comprehensive set of microbiological assays to identify the likely bacterial, viral and protozoal etiologies. The selected assays effected a balanced consideration of cost, robustness and performance, and all assays were performed at the study sites. Identification of bacterial pathogens employed streamlined conventional bacteriologic biochemical and serological algorithms. Diarrheagenic Escherichia coli were identified by application of a multiplex polymerase chain reaction assay for enterotoxigenic, enteroaggregative, and enteropathogenic E. coli. Rotavirus, adenovirus, Entamoeba histolytica, Giardia enterica, and Cryptosporidium species were detected by commercially available enzyme immunoassays on stool samples. Samples positive for adenovirus were further evaluated for adenovirus serotypes 40 and 41. We developed a novel multiplex assay to detect norovirus (types 1 and 2), astrovirus, and sapovirus. The portfolio of diagnostic assays used in the GEMS study can be broadly applied in developing countries seeking robust cost-effective methods for enteric pathogen detection.

  18. Postmenopausal hormone therapy and ductal carcinoma in situ: A population-based case control study

    PubMed Central

    Calvocoressi, Lisa; Stowe, Meredith H.; Carter, Darryl; Claus, Elizabeth B.

    2013-01-01

    Background and aim The relationship between hormone therapy (HT) and invasive breast cancer has been extensively investigated, but the relationship between HT and in situ breast cancer has received relatively little attention. We examined the relationship between HT and ductal carcinoma in situ (DCIS) among postmenopausal women who participated in a population-based case control study in Connecticut, USA. Methods This analysis included 1,179 post-menopausal women (603 controls and 576 cases), who comprised a subset of a population-based case-control study that included all incident cases of breast carcinoma in situ (BCIS) in Connecticut and frequency-matched controls by 5-year age intervals. Results We found no association between DCIS and ever use of any HT (adjusted odds ratio (OR) = 0.85, 95 % confidence interval (CI): 0.65-1.11); of estrogen alone (adjusted OR = 0.93; 95 % CI: 0.68-1.29) or of estrogen and progesterone (adjusted OR = 0.75; 95 % CI: 0.52-1.08). There was also no association between DCIS and current use of these hormones. In addition, estimated risk of DCIS did not increase with duration of use of these preparations. Conclusions These results add to a small literature that remains inconclusive. To determine whether HT poses risk of in situ breast cancer, larger studies with greater power and precise control of important covariates (e.g., mammography screening) are needed, as are meta-analyses of available data. PMID:22317899

  19. Case-control study of vulvar vestibulitis risk associated with genital infections.

    PubMed Central

    Smith, Elaine M; Ritchie, Justine M; Galask, Rudolph; Pugh, Erica E; Jia, Jian; Ricks-McGillan, Joan

    2002-01-01

    OBJECTIVE: To evaluate the risk of vulvar vestibulitis syndrome (VVS) associated with genital infections in a case-control study. METHODS: Diagnosed cases with VVS (n = 69) and age-frequency-matched healthy controls (n = 65) were enrolled from gynecology clinics in a university medical hospital during 1999. They were compared for potential risk factors and symptoms of disease. RESULTS: VVS cases had a significantly higher risk of physician-reported bacterial vaginosis (BV) (odds ratio, OR = 9.4), Candida albicans (OR = 5.7), pelvic inflammatory disease (PID) (OR = 11.2), trichomoniasis (OR = 20.6), and vulvar dysplasia (OR = l5.7) but no risk associated with human papillomavirus (HPV), ASCUS, cervical dysplasia, genital warts, chlamydia, genital herpes or gonorrhea. Genital symptoms reported significantly more often with VVS included vulvar burning (91 vs. 12%), dyspareunia (81 vs. 15%), vulvar itching (68 vs. 23%) and dysuria (54 vs. 19%) (p < 0.0001). CONCLUSION: A history of genital infections is associated with an increased risk of VVS. Long-term follow-up case-control studies are needed to elucidate etiologic mechanisms, methods for prevention and effective treatment. PMID:12648313

  20. Control selection methods in recent case-control studies conducted as part of infectious disease outbreaks.

    PubMed

    Waldram, Alison; McKerr, Caoimhe; Gobin, Maya; Adak, Goutam; Stuart, James M; Cleary, Paul

    2015-06-01

    Successful investigation of national outbreaks of communicable disease relies on rapid identification of the source. Case-control methodologies are commonly used to achieve this. We assessed control selection methods used in recently published case-control studies for methodological and resource issues to determine if a standard approach could be identified. Neighbourhood controls were the most frequently used method in 53 studies of a range of different sizes, infections and settings. The most commonly used method of data collection was face to face interview. Control selection issues were identified in four areas: method of identification of controls, appropriateness of controls, ease of recruitment of controls, and resource requirements. Potential biases arising from the method of control selection were identified in half of the studies assessed. There is a need to develop new ways of selecting controls in a rapid, random and representative manner to improve the accuracy and timeliness of epidemiological investigations and maximise the effectiveness of public health interventions. Innovative methods such as prior recruitment of controls could improve timeliness and representativeness of control selection.

  1. Bayesian sample size determination for case-control studies when exposure may be misclassified.

    PubMed

    Joseph, Lawrence; Bélisle, Patrick

    2013-12-01

    Odds ratios are frequently used for estimating the effect of an exposure on the probability of disease in case-control studies. In planning such studies, methods for sample size determination are required to ensure sufficient accuracy in estimating odds ratios once the data are collected. Often, the exposure used in epidemiologic studies is not perfectly ascertained. This can arise from recall bias, the use of a proxy exposure measurement, uncertain work exposure history, and laboratory or other errors. The resulting misclassification can have large impacts on the accuracy and precision of estimators, and specialized estimation techniques have been developed to adjust for these biases. However, much less work has been done to account for the anticipated decrease in the precision of estimators at the design stage. Here, we develop methods for sample size determination for odds ratios in the presence of exposure misclassification by using several interval-based Bayesian criteria. By using a series of prototypical examples, we compare sample size requirements after adjustment for misclassification with those required when this problem is ignored. We illustrate the methods by planning a case-control study of the effect of late introduction of peanut to the diet of children to the subsequent development of peanut allergy.

  2. Human papillomaviruses in colorectal cancers: A case-control study in western patients.

    PubMed

    Vuitton, Lucine; Jaillet, Carine; Jacquin, Elise; Monnien, Franck; Heberle, Marine; Mihai, Maria I; Lassabe, Catherine; Raffoul, Johnny; Puyraveau, Marc; Lakkis, Zaher; Lamfichekh, Najib; Picard, Alain; Prétet, Jean-Luc; Mougin, Christiane; Valmary-Degano, Séverine

    2017-04-01

    Colorectal cancer (CRC) is one of the most common cancers. As in other cancer locations, the involvement of human papillomaviruses (HPV) has been suggested but remains highly debated with wide differences among reported prevalence of HPV infection in CRCs. To determine the actual prevalence of high risk HPV16 and 18 in a large case-control study. CRC specimens were used for analysis of both tumor and distant healthy tissue. As a non-malignant control group, samples from sigmoid diverticulosis resections were studied. Detection of HPV16 and HPV18 DNA was performed using a real time polymerase chain reaction (qPCR). Ten percent of tumor samples were also randomly subjected to a complete HPV genotyping using the INNO-LiPA technique. 467 samples were analyzed: 217 tumor samples from 210 CRCs, 210 distant healthy tissue samples, and 40 sigmoid samples. HPV18 DNA was never amplified and HPV16 was amplified only three times in tumor tissues with viral loads under or at the limit of quantification. New extraction from the same tumor blocks for these samples revealed no HPV with qPCR and INNO-Lipa assays. With adequate procedures and reliable techniques, no HPV was detected in the largest case-control study so far, bringing more evidence on the absence of involvement of HPV in CRCs. Copyright © 2016 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

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

    PubMed

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

    2016-01-01

    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. 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. 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. 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.

  4. Efficacy and safety of Innoseal for air leak after pulmonary resection: a case-control study.

    PubMed

    Petrella, Francesco; Borri, Alessandro; Brambilla, Daniela; Calanca, Giorgio; Vezzani, Nicola; Colantoni, Antonio; Gasparetto, Adolfo; Spaggiari, Lorenzo

    2016-11-01

    Prolonged air leak is one of the most common complications after lung surgery and the cause of prolonged hospital stay frequently associated with major postoperative morbidity and thus responsible for even higher hospital costs. This case-control study was designed to test the sealing efficacy and safety of Enable-Innoseal TP4 in patients undergoing pulmonary resection for lung cancer. This was a case-control trial enrolling patients with primary or single site metastatic lung cancer scheduled for elective anatomic or nonanatomic pulmonary resection presenting intraoperative grade 1 or 2 air leak at water submersion test; the study group population was then matched 1:1 according to surgical procedure, male/female ratio, preoperative FEV1, and age. In the study population, 21 patients (70.0%) presented intraoperative grade 1 air leak and 9 patients grade 2 (30.0%) air leak; after comparison with the control group, we observed a significant shorter time for chest drain removal in the study population (P = 0.0050), whereas no difference was registered in terms of number of days needing for discharge (P = 0.0762). Enable-Innoseal TP4 was effective in treating limited intraoperative air leaks after pulmonary resection and preventing prolonged postoperative air leaks in patients receiving either anatomic or nonanatomic lung resections. Further randomized double-arm studies are required to confirm the efficacy of Enable-Innoseal TP4 demonstrated by this pilot study. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. 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

  6. 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

  7. Testing goodness-of-fit for the proportional hazards model based on nested case-control data.

    PubMed

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

    2014-12-01

    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 article, 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. © 2014, The International Biometric Society.

  8. Evaluation of Feasibility for a Case-Control Study of Pituitary-Ovarian Function in Premenopausal Women With Breast Cancer

    DTIC Science & Technology

    2006-07-01

    case-control study that uses gonadotropin releasing hormone (GnRH) agonist stimulation tests to compare pituitary -ovarian function in premenopausal women...in responsiveness of ovarian hormones to gonadotropin releasing hormone (GnRH) stimulation in healthy premenopausal women. GnRH stimulation was...determine the safety and feasibility of conducting a case-control study that uses gonadotropin releasing hormone (GnRH) stimulation tests to evaluate

  9. Evaluation of Feasibility for a Case-Control Study of Pituitary-Ovarian Function in Premenopausal Women with Breast Cancer

    DTIC Science & Technology

    2005-07-01

    feasibility of a case-control study that uses gonadotropin releasing hormone (GnRH) stimulation tests to evaluate sensitivity of the hypothalamic...determine the safety and feasibility of conducting a case-control study that uses gonadotropin releasing hormone (GnHR) stimulation tests to evaluate...women. The full-scale study will determine if: 1) the anterior pituitary of pre-menopausal women with breast cancer secretes more luteinizing hormone (LH

  10. 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

  11. A retrospective likelihood approach for efficient integration of multiple omics factors in case-control association studies.

    PubMed

    Balliu, Brunilda; Tsonaka, Roula; Boehringer, Stefan; Houwing-Duistermaat, Jeanine

    2015-03-01

    Integrative omics, the joint analysis of outcome and multiple types of omics data, such as genomics, epigenomics, and transcriptomics data, constitute a promising approach for powerful and biologically relevant association studies. These studies often employ a case-control design, and often include nonomics covariates, such as age and gender, that may modify the underlying omics risk factors. An open question is how to best integrate multiple omics and nonomics information to maximize statistical power in case-control studies that ascertain individuals based on the phenotype. Recent work on integrative omics have used prospective approaches, modeling case-control status conditional on omics, and nonomics risk factors. Compared to univariate approaches, jointly analyzing multiple risk factors with a prospective approach increases power in nonascertained cohorts. However, these prospective approaches often lose power in case-control studies. In this article, we propose a novel statistical method for integrating multiple omics and nonomics factors in case-control association studies. Our method is based on a retrospective likelihood function that models the joint distribution of omics and nonomics factors conditional on case-control status. The new method provides accurate control of Type I error rate and has increased efficiency over prospective approaches in both simulated and real data.

  12. Case-control studies of sporadic enteric infections: a review and discussion of studies conducted internationally from 1990 to 2009.

    PubMed

    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

    2012-04-01

    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.

  13. Multicenter patient records research: security policies and tools.

    PubMed

    Behlen, F M; Johnson, S 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.

  14. 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.

  15. Risk factors of Streptococcus suis infection in Vietnam. A case-control study.

    PubMed

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

    2011-03-08

    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. 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 (OR(1) = 2.22; 95%CI = [1.15-4.28] and OR(2) = 4.44; 95%CI = [2.15-9.15]), occupations related to pigs (OR(1) = 3.84; 95%CI = [1.32-11.11] and OR(2) = 5.52; 95%CI = [1.49-20.39]), and exposures to pigs or pork in the presence of skin injuries (OR(1) = 7.48; 95%CI = [1.97-28.44] and OR(2) = 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. 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.

  16. Zinc Intake and Risk of Prostate Cancer: Case-Control Study and Meta-Analysis

    PubMed Central

    Dabbous, Firas; Ali, Mohamed M.; Batai, Ken; Shah, Ebony; Kittles, Rick A.

    2016-01-01

    Zinc is an essential dietary element that has been implicated in the pathogenesis of prostate cancer, a cancer that disproportionately affects men of African descent. Studies assessing the association of zinc intake and prostate cancer have yielded inconsistent results. Furthermore, very little is known about the relationship between zinc intake and prostate cancer among African Americans. We examined the association between self-reported zinc intake and prostate cancer in a hospital-based case-control study of African Americans. We then compared our results with previous studies by performing a meta-analysis to summarize the evidence regarding the association between zinc and prostate cancer. Newly diagnosed African American men with histologically confirmed prostate cancer (n = 127) and controls (n = 81) were recruited from an urban academic urology clinic in Washington, DC. Controls had higher zinc intake, with a mean of 14 mg/day versus 11 mg/day for cases. We observed a non-significant, non-linear increase in prostate cancer when comparing tertiles of zinc intake (OR <6.5 vs 6.5–12.5mg/day 1.8, 95% CI: 0.6,5.6; OR <6.5 vs >12.5mg/day 1.3, 95% CI: 0.2,6.5). The pooled estimate from 17 studies (including 3 cohorts, 2 nested case-control, 11 case-control studies, and 1 randomized clinical trial, with a total of 111,199 participants and 11,689 cases of prostate cancer) was 1.07hi vs lo 95% CI: 0.98–1.16. Using a dose-response meta-analysis, we observed a non-linear trend in the relationship between zinc intake and prostate cancer (p for nonlinearity = 0.0022). This is the first study to examine the relationship between zinc intake in black men and risk of prostate cancer and systematically evaluate available epidemiologic evidence about the magnitude of the relationship between zinc intake and prostate cancer. Despite of the lower intake of zinc by prostate cancer patients, our meta-analysis indicated that there is no evidence for an association between zinc

  17. A cohort mortality and nested case-control study of French and Austrian talc workers

    PubMed Central

    Wild, P; Leodolter, K; Refregier, M; Schmidt, H; Zidek, T; Haidinger, G

    2002-01-01

    Objectives: To study whether the mortality from non-malignant and malignant respiratory diseases of workers employed in French and Austrian talc mines and mills is related to their long term occupational exposure. Methods: Two historical cohorts were set up comprising all male subjects who had been working continuously for at least 1 year in a series of talc producing companies in France and Austria. The French cohort consisted of those employed at a site in the French Pyrenees and working between 1 January 1945 and 31 December 1994. The Austrian cohort consisted of the workers employed between 1 January 1972 and 31 December 1995 in one of four industrial sites in the Austrian Alps. The mortality within the cohorts was compared with local death rates. Two nested case-control studies focusing on non-malignant and malignant respiratory diseases were set up to estimate possible dose-response relations with cumulative exposure to talc dust based on an industry specific job exposure matrix. Results: Mortality from lung cancer was in small excess in both cohorts (France, standardised mortality ratio (SMR) 1.23, 21 cases observed, 95% confidence interval (95% CI) 0.76 to 1.89; Austria, SMR 1.06, seven observed, 95% CI 0.43 to 2.19). A non-significant excess mortality was found for all non-malignant respiratory diseases in the French cohort due to a significant excess for pneumoconiosis (SMR 5.56, three observed, 95% CI 1.12 to 16.2). The case-control study of non-malignant respiratory disease showed an increased mortality in the highest exposure groups (odds ratio (OR) 2.5 for a cumulative exposure ≥800 y.mg/m3) with a significant trend (OR/100 y.mg/m3 1.08) with cumulative exposure to talc. On the contrary, no increasing trend could be found in the case-control study of lung cancer. This result must be interpreted considering the small cohort size. Adjustment on smoking and exposure to quartz did not influence these results to any extent. Conclusions: The mortality

  18. Retrieval of the Leadless Cardiac Pacemaker: A Multicenter Experience.

    PubMed

    Reddy, Vivek Y; Miller, Marc A; Knops, Reinoud E; Neuzil, Petr; Defaye, Pascal; Jung, Werner; Doshi, Rahul; Castellani, Mark; Strickberger, Adam; Mead, R Hardwin; Doppalapudi, Harish; Lakkireddy, Dhanunjaya; Bennett, Matthew; Sperzel, Johannes

    2016-12-01

    Leadless cardiac pacemakers have emerged as a safe and effective alternative to conventional transvenous single-chamber ventricular pacemakers. Herein, we report a multicenter experience on the feasibility and safety of acute retrieval (<6 weeks) and chronic retrieval (>6 weeks) of the leadless cardiac pacemaker in humans. This study included patients enrolled in 3 multicenter trials, who received a leadless cardiac pacemaker implant and who subsequently underwent a device removal attempt. The overall leadless pacemaker retrieval success rate was 94%: for patients whose leadless cardiac pacemaker had been implanted for <6 weeks (acute retrieval cohort), complete retrieval was achieved in 100% (n=5/5); for those implanted for ≥ 6 weeks (chronic retrieval cohort), retrieval was achieved in 91% (n=10/11) of patients. The mean duration of time from implant to retrieval attempt was 346 days (range, 88-1188 days) in the chronic retrieval cohort, and nearly two thirds (n=7; 63%) had been implanted for >6 months before the retrieval attempt. There were no procedure-related adverse events at 30 days post retrieval procedure. This multicenter experience demonstrated the feasibility and safety of retrieving a chronically implanted single-chamber (right ventricle) active fixation leadless pacemaker. URL: https://www.clinicaltrials.gov. Unique identifiers: NCT02051972, NCT02030418, and NCT01700244. © 2016 American Heart Association, Inc.

  19. A new statistical approach to detecting differentially methylated loci for case control Illumina array methylation data.

    PubMed

    Chen, Zhongxue; Liu, Qingzhong; Nadarajah, Saralees

    2012-04-15

    As an epigenetic alteration, DNA methylation plays an important role in epigenetic controls of gene transcription. Recent advances in genome-wide scan of DNA methylation provide great opportunities in studying the impact of DNA methylation on many human diseases including various types of cancer. Due to the unique feature of this type of data, applicable statistical methods are limited and new sophisticated approaches are desirable. In this article, we propose a new statistical test to detect differentially methylated loci for case control methylation data generated by Illumina arrays. This new method utilizes the important finding that DNA methylation is highly correlated with age. The proposed method estimates the overall P-value by combining the P-values from independent individual tests each for one age group. Through real data application and simulation study, we show that the proposed test is robust and usually more powerful than other methods.

  20. Risk factors in lateral epicondylitis (tennis elbow): a case-control study.

    PubMed

    Titchener, A G; Fakis, A; Tambe, A A; Smith, C; Hubbard, R B; Clark, D I

    2013-02-01

    Lateral epicondylitis is a common condition, but relatively little is known about its aetiology and associated risk factors. We have undertaken a large case-control study using The Health Improvement Network database to assess and quantify the relative contributions of some constitutional and environmental risk factors for lateral epicondylitis in the community. Our dataset included 4998 patients with lateral epicondylitis who were individually matched with a single control by age, sex, and general practice. The median age at diagnosis was 49 (interquartile range 42-56) years . Multivariate analysis showed that the risk factors associated with lateral epicondylitis were rotator cuff pathology (OR 4.95), De Quervain's disease (OR 2.48), carpal tunnel syndrome (OR 1.50), oral corticosteroid therapy (OR 1.68), and previous smoking history (OR 1.20). Diabetes mellitus, current smoking, trigger finger, rheumatoid arthritis, alcohol intake, and obesity were not found to be associated with lateral epicondylitis.

  1. Case-Control Study of Risk Factors for Meningococcal Disease in Chile.

    PubMed

    Olea, Andrea; Matute, Isabel; González, Claudia; Delgado, Iris; Poffald, Lucy; Pedroni, Elena; Alfaro, Tania; Hirmas, Macarena; Nájera, Manuel; Gormaz, Ana; López, Darío; Loayza, Sergio; Ferreccio, Catterina; Gallegos, Doris; Fuentes, Rodrigo; Vial, Pablo; Aguilera, Ximena

    2017-07-01

    An outbreak of meningococcal disease with a case-fatality rate of 30% and caused by predominantly serogroup W of Neisseria meningitidis began in Chile in 2012. This outbreak required a case-control study to assess determinants and risk factors for infection. We identified confirmed cases during January 2012-March 2013 and selected controls by random sampling of the population, matched for age and sex, resulting in 135 case-patients and 618 controls. Sociodemographic variables, habits, and previous illnesses were studied. Analyses yielded adjusted odds ratios as estimators of the probability of disease development. Results indicated that conditions of social vulnerability, such as low income and overcrowding, as well as familial history of this disease and clinical histories, especially chronic diseases and hospitalization for respiratory conditions, increased the probability of illness. Findings should contribute to direction of intersectoral public policies toward a highly vulnerable social group to enable them to improve their living conditions and health.

  2. [A population-based case control study of primary liver cancer in Fusui].

    PubMed

    Zhang, M D

    1993-02-01

    A population-based case control study of primary liver cancer (PLC) was undertaken in Fusui County, Guangxi Autonomous Region. Ninety-nine PLC cases and 99 age-sex-matched controls were surveyed for their general conditions, life style features, dietary habits, types of drinking water and family history. Cases and controls were well distributed in nationality, education, marital status and annual income per person. Conditional logistic regression results showed that HBV infection, drinking pond-ditch water, family history and total alcohol intake were the risk factors of PLC with the relative risks 5.330 (2.502-11.35), 3.703 (1.251-10.96), 2.881 (1.289-6.441), 1.002 (1.000-1.004), respectively. And antibody of HBV surface antigen is protective factor with the relative risk of 0.418 (0.210-0.834).

  3. Tobacco chewing and risk of gastric cancer: a case-control study in Yemen.

    PubMed

    Al-Qadasi, F A; Shah, S A; Ghazi, H F

    2017-01-23

    This study aimed to assess the risk factors for gastric cancer in Yemen. A hospital-based case-control study of 70 cases and 140 controls was carried out in Sana'a city between May and October 2014. A structured questionnaire was used to collect information through direct interview. Living in rural areas, tobacco chewing and drinking untreated water were significant risk factors for gastric cancer. Frequent consumption of chicken, cheese, milk, starchy vegetables, cucumber, carrots, leeks, sweet pepper, fruit drinks, legumes and olive oil were associated significantly with decreased risk of gastric cancer. Multiple logistic regression analysis showed that chewing tobacco and frequent consumption of white bread were associated with increased risk of gastric cancer, whereas frequent consumption of chicken, cooked potatoes and fruit drinks had an inverse association. Risk of gastric cancer can be prevented by health education and increasing community awareness.

  4. Dietary total antioxidant capacity and the risk of breast cancer: a case-control study.

    PubMed

    Karimi, Z; Bahadoran, Z; Abedini, S; Houshyar-Rad, A; Rashidkhani, B

    2015-09-28

    There is growing evidence that dietary antioxidants may have favourable effects in reducing cancer risk. In a case-control study we investigated the association of dietary total antioxidant capacity (TAC) and risk of breast cancer. Sociodemographic data, medical history and anthropometric measurements were collected from 275 women (100 breast cancer cases & 175 controls). Participants' usual dietary intake was measured using a validated semi-quantitative food frequency questionnaire and their dietary TAC was estimated. An inverse, but non-significant, association was observed between dietary TAC and breast cancer risk. Multiple logistic regression models based on TAC of individual food groups showed that consumption of fruits and vegetables with higher TAC (μmolTE/100 g) was associated with a significantly decreased risk of breast cancer. Our study supports a protective effect of dietary antioxidants in relation to breast cancer risk. Food selection based on TAC of foods may be an effective strategy to modify the risk of cancer.

  5. [Voice disorders related to job stress in teaching: a case-control study].

    PubMed

    Giannini, Susana Pimentel Pinto; Latorre, Maria do Rosário Dias de Oliveira; Ferreira, Leslie Piccolotto

    2012-11-01

    This case-control study aimed to test the association between voice disorders and job stress among public schoolteachers in São Paulo, Brazil. The groups consisted of teachers with (n = 165) and without (n = 105) voice-related complaints. Both groups answered the questionnaires Conditions of Vocal Production and Job Stress Scale. Analysis of cases and controls showed comparable samples, differing only by vocal symptoms. There was a statistically significant difference between cases and controls in relation to job stress involving high strain (OR = 2.1; 95%CI: 1.1-3.9), which places high demands combined with low job control. High strain in cases in this study represents the highest risk of physical and mental disorders for teachers. Loss of voice prevents teachers from continuing in their professional role, eliminates their professional identity, and jeopardizes their career.

  6. 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.

  7. Effect of suboptimal breast-feeding on occurrence of autism: a case-control study.

    PubMed

    Al-Farsi, Yahya M; Al-Sharbati, Marwan M; Waly, Mostafa I; Al-Farsi, Omar A; Al-Shafaee, Mohammed A; Al-Khaduri, Maha M; Trivedi, Malav S; Deth, Richard C

    2012-07-01

    To evaluate the association between suboptimal breast-feeding practices and autism spectrum disorders (ASDs). A case-control study was conducted in 102 ASD cases and 102 matched healthy controls. Based on adjusted odds ratios from logistic regression models, ASD was found to be associated with the late initiation of breast-feeding (odds ratio 1.48, 95% confidence interval 1.01-3.1), a non-intake of colostrum (odds ratio 1.7, 95% confidence interval 1.03-4.3), prelacteal feeding, and bottle-feeding. The risk of ASD was found to decrease in a dose-response fashion over increasing periods of exclusive breast-feeding (P for trend = 0.04) and continued breast-feeding (P for trend = 0.001). The study indicates that increased ASD risk is generally associated with suboptimal breast-feeding practices. Copyright © 2012 Elsevier Inc. All rights reserved.

  8. Postadmission sepsis as a screen for quality problems: a case-control study.

    PubMed

    Hughes, John S; Eisenhandler, Jon; Goldfield, Norbert; Weinberg, Patti G; Averill, Richard

    2014-01-01

    The present on admission (POA) indicator used with diagnosis codes listed in hospital discharge abstracts makes it possible to screen for possible in-hospital complications, which may in turn point to quality of care problems. A case-control study was performed among 382 patients from 30 New York State hospitals to see if lapses in quality were associated with the development of postadmission sepsis. Cases with hospital-acquired sepsis (labeled not POA) were compared with matched controls without sepsis. The authors found that central venous catheters and emergently inserted peripheral intravenous catheters were associated with subsequent development of sepsis. Urethral catheters were associated with sepsis for medical patients but not for surgical patients. Adherence to several process of care guidelines was incomplete but none occurred statistically significantly more frequently among sepsis cases than controls. Using discharge abstract diagnosis codes to determine the presence of postadmission complications shows promise for identifying areas for quality improvement.

  9. Case-control study of intracranial meningiomas in women in Los Angeles County, California

    SciTech Connect

    Preston-Martin, S.; Paganini-Hill, A.; Henderson, B.E.; Pike, M.C.; Wood, C.

    1980-07-01

    A case-control study was conducted among women in Los Angeles County to investigate possible causes of intracranial meningiomas. Questionnaires sought information from patients and from a neighbor of each one on characteristics and past experiences that might be associated with the development of this disease. Information was obtained on 188 matched patient-neighbor pairs. Three primary factors appeared to be associated with meningioma occurrence: 1) a history of head trauma (odds ratio = 2.0, p = 0.01), 2) consumption of certain cured meats (odds ratio = 2.8, p = less than 0.01), and 3) exposure to medical and dental diagnostic X-rays to the head. For diagnostic X-rays, the strongest association was with early exposure (less than 20 yr old) to full-mouth dental X-ray series (odds ratio = 4.0, p less than 0.01).

  10. Culture, risk factors and suicide in rural China: a psychological autopsy case control study

    PubMed Central

    Zhang, J.; Conwell, Y.; Zhou, L.; Jiang, C.

    2009-01-01

    Objective Previous research on sociocultural factors for Chinese suicide have been basically limited to single case studies or qualitative research with ethnographic methodology. The current study examines the major risk factors and some cultural uniqueness related to Chinese rural suicide using a quantitative design. Method This is a case control study with 66 completed suicides and 66 living controls obtained from psychological autopsy interviews in rural China. Results Both bivariate analyses and the multiple regression model have found that the Chinese rural suicide patterns are basically similar to those in most other cultures in the world: strong predictors of rural Chinese suicide are the psychopathological, psychological, and physical health variables, followed by social support and negative and stressful life events. Other significant correlates include lower education, poverty, religion, and family disputes. Conclusion Culture has an important impact on suicide patterns in a society. PMID:15521827

  11. 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.

  12. A case control study on the lung cancer risk factors in north of Iran.

    PubMed

    Karimzadeh, Laleh; Koohdani, Fariba; Siassi, Fereydoon; Mahmoudi, Mahmoud; Moslemi, Dariush; Shokrzadeh, Mohammad; Safari, Farid

    2011-01-01

    In this case control study, the risk factors of lung cancer was assessed in the north of Iran. Two groups were matched for gender and age (+/- 5 years). Data were collected from 40 cases and 40 controls attending to hospitals. A public information questionnaire was used for data collection. Incidence odds ratios (OR) and corresponding 95% confidence intervals calculated using logistic regression analyses. Results showed that in adjusted odd ratio positive family history of cancer (OR = 0/19, 95% CI: 0/04-0/8) was associated with a reduction, and consumption of baked bread in traditional oven (OR = 22/6, 95% CI: 1/9-270), was associated with increase in lung cancer risk. Based on the results, smoking was not correlated with lung cancer. In conclusion, the data offers consumption of traditional oven-baked bread may enhance the risk of lung cancer but positive family history of cancer may reduce it.

  13. Association between psoas abscess and prosthetic hip infection: a case-control study.

    PubMed

    Dauchy, Frédéric-Antoine; Dupon, Michel; Dutronc, Hervé; de Barbeyrac, Bertille; Lawson-Ayayi, Sylvie; Dubuisson, Vincent; Souillac, Vincent

    2009-04-01

    The relationship between prosthetic hip infection and a psoas abscess is poorly documented. We determined the frequency of prosthetic hip infections associated with psoas abscesses and identified their determinants. We conducted a 2-year observational study. Data from patients with psoas abscesses that were associated with prosthetic hip infections were examined in a case-control study. Of 106 patients admitted to the Infectious Diseases Department with prosthetic hip infection, 13 also had a psoas abscess (12%; 95% CI: 6-19). By conditional logistic regression analysis, psoas abscesses were observed more frequently in cases of hematogenous prosthetic infections (OR = 93, p = 0.06) and in patients with a history of neoplasm (OR = 20, p = 0.03). Our results suggest that the presence of psoas abscesses is a frequent but under-diagnosed complication of prosthetic hip infection. We recommend that an abdominal CT scan be performed on patients with hematogenous prosthetic hip infection or with a history of neoplasm.

  14. Chemical exposures and Parkinson's disease: a population-based case-control study.

    PubMed

    Frigerio, Roberta; Sanft, Kevin R; Grossardt, Brandon R; Peterson, Brett J; Elbaz, Alexis; Bower, James H; Ahlskog, J Eric; de Andrade, Mariza; Maraganore, Demetrius M; Rocca, Walter A

    2006-10-01

    The putative association between pesticide exposures and Parkinson's disease (PD) remains controversial. We identified all subjects who developed PD in Olmsted County, Minnesota, from 1976 through 1995, and matched them by age (+/- 1 year) and sex to general population controls. We assessed exposures to chemical products by means of telephone interview with cases, controls, or their proxies (149 cases; 129 controls). Exposure to pesticides related or unrelated to farming was associated with PD in men (odds ratio, 2.4; 95% confidence interval, 1.1-5.4; P = 0.04). The association remained significant after adjustment for education or smoking. Analyses for the other six categories of industrial and household chemicals were all nonsignificant. This population-based study suggests a link between pesticides use and PD that is restricted to men. Pesticides may interact with other genetic or nongenetic factors that are different in men and women.

  15. A case-control study of pancreatic cancer and cigarettes, alcohol, coffee and diet.

    PubMed Central

    Olsen, G W; Mandel, J S; Gibson, R W; Wattenberg, L W; Schuman, L M

    1989-01-01

    A pancreatic cancer case-control study was conducted in the Minneapolis-St. Paul area. Family members were interviewed about the subject's usage of cigarettes, alcohol, coffee, and other dietary factors in the two years prior to death (cases, n = 212) or prior to interview (controls, n = 220). The adjusted odds ratio for two packs or more of cigarettes per day was 3.92 (95% CI = 1.18, 13.01) and four or more drinks per day OR 2.69 (95% CI = 1.00, 7.27). Coffee was not a risk factor (seven cups or more per day; OR 0.58 (95% CI = 0.27, 1.27). A positive trend was observed for beef and pork consumption, and a negative trend from cruciferous vegetables. PMID:2751016

  16. 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.

  17. Adherence to Buprenorphine Maintenance Treatment in Opioid Dependence Syndrome: A Case Control Study

    PubMed Central

    Bandawar, Mrunal; Kandasamy, Arun; Chand, Prabhat; Murthy, Pratima; Benegal, Vivek

    2015-01-01

    Background: Opioid Use disorders are emerging as a serious public health concern in India. Opioid substitution treatment is one of the emerging forms of treatment in this population which needs more evidence to increase its availability and address prejudices towards the same. Materials and Methods: This is a case control study with retrospective design reviewing the charts of patients with opioid dependence syndrome registered between January 2005 to December 2012. Adherence to treatment was the outcome variable assessed in this study. Results: The odds of the Buprenorphine Maintenance Treatment (BMT) group remaining in treatment is 4.5 (P < 0.005) times more than Naltrexone Maintenance Treatment (NMT) group and 7 times (P < 0.001) more than Psychosocial intervention (PST) alone group. Discussion: We believe that these study findings will help in reducing the prejudice towards BMT and encourage further research in this field. Conclusion: BMT has a better adherence rate than other treatments in opioid use disorders. PMID:26664083

  18. Lifestyle factors including diet and leukemia development: a case-control study from Mumbai, India.

    PubMed

    Balasubramaniam, Ganesh; Saoba, Sushama Laxman; Sarhade, Monika Nilesh; Kolekar, Suvarna Anand

    2013-01-01

    In India, among males, leukemia rates vary across the country. The present unmatched hospital-based case- control study conducted at Tata Memorial Hospital included subjects registered between the years 1997-99. There were 246 leukemia cases and 1,383 normal controls. Data on demographics, lifestyle, diet and occupation history were recorded. Cigarette (OR=2.1) and bidi smoking (OR=3.4) showed excess risk for leukemia. Odds ratios were 3.9 for fish-eaters, 0.40 for chilli eaters, 1.5 for milk drinkers and 0.60 for coffee drinkers, compared to non-drinkers/eaters. However, neither exposure to use of pesticides nor cotton dust showed any excess risk for leukemia.

  19. Risk factors for campylobacter infection in infants and young children: a matched case-control study.

    PubMed

    Tenkate, T D; Stafford, R J

    2001-12-01

    Campylobacter infection has one of the highest rates of all the notifiable diseases in Australia, with a peak in children aged 0-35 months. A matched case-control study was conducted to investigate risk factors for campylobacter infection for children in this age group. Eighty-one cases and 144 controls were enrolled in the study that was conducted between 24 January 1996 and 21 January 1997. The following risk factors were found to be independently associated with illness: ownership of pet puppies (adjusted odds ratio [OR] 16.58, 95% confidence interval [CI] 3.73-73.65) and pet chickens (OR 11.80, CI 1.37-101.75), and consumption of mayonnaise (OR 4.13, CI 1.61-10.59). We propose that children aged less than 3 years are at risk of campylobacter infection if residing in a household which has puppies or chickens as pets.

  20. High reprint orders in medical journals and pharmaceutical industry funding: case-control study.

    PubMed

    Handel, Adam E; Patel, Sunil V; Pakpoor, Julia; Ebers, George C; Goldacre, Ben; Ramagopalan, Sreeram V

    2012-06-28

    To assess the extent to which funding and study design are associated with high reprint orders. Case-control study. Top articles by size of reprint orders in seven journals, 2002-09. Lancet, Lancet Neurology, Lancet Oncology (Lancet Group), BMJ, Gut, Heart, and Journal of Neurology, Neurosurgery & Psychiatry (BMJ Group) matched to contemporaneous articles not in the list of high reprint orders. Funding and design of randomised controlled trials or other study designs. Median reprint orders for the seven journals ranged from 3000 to 126,350. Papers with high reprint orders were more likely to be funded by the pharmaceutical industry than were control papers (industry funding versus other or none: odds ratio 8.64, 95% confidence interval 5.09 to 14.68, and mixed funding versus other or none: 3.72, 2.43 to 5.70). Funding by the pharmaceutical industry is associated with high numbers of reprint orders.

  1. 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.

  2. Putative risk factors in developmental dyslexia: a case-control study of Italian children.

    PubMed

    Mascheretti, Sara; Marino, Cecilia; Simone, Daniela; Quadrelli, Ermanno; Riva, Valentina; Cellino, Maria Rosaria; Maziade, Michel; Brombin, Chiara; Battaglia, Marco

    2015-01-01

    Although dyslexia runs in families, several putative risk factors that cannot be immediately identified as genetic predict reading disability. Published studies analyzed one or a few risk factors at a time, with relatively inconsistent results. To assess the contribution of several putative risk factors to the development of dyslexia, we conducted a case-control study of 403 Italian children, 155 with dyslexia, by implementing a stepwise logistic regression applied to the entire sample, and then to boys and girls separately. Younger parental age at child's birth, lower parental education, and risk of miscarriage significantly increased the odds of belonging to the dyslexia group (19.5% of the variation). These associations were confirmed in the analyses conducted separately by sex, except for parental education, which significantly affected only males. These findings support reading disabilities as a multifactorial disorder and may bear some importance for the prevention and/or early detection of children at heightened risk for dyslexia.

  3. Occupation and risk of pancreatic cancer: a population-based case-control study in iowa.

    PubMed

    Zhang, Yawei; Cantor, Kenneth P; Lynch, Charles F; Zhu, Yong; Zheng, Tongzhang

    2005-04-01

    Previous epidemiological studies have inconsistently linked various occupations and industries to pancreatic cancer risk. We analyzed data from a population-based case-control study conducted in Iowa involving 376 histologically confirmed incident pancreatic cancer cases and 2434 control subjects. A significantly increased risk was observed among men who worked in the following industries: chemical and allied products, transportation, and elementary and secondary schools. Increased risks also were observed in men who were employed as truck drivers; railroad brake, signal, and switch operators; purchasing agents and buyers; teachers; insurance agents; and retail supervisors. Among women, a significantly increased risk of pancreatic cancer was found for employment in furniture and home furnishing stores, and a borderline significantly increased risk among textile sewing machine operators and tenders. Working in several occupations and industries was associated with an increased risk of pancreatic cancer in this study, and these associations warrant further investigation.

  4. Occupation and thyroid cancer: a population-based case-control study in Connecticut

    PubMed Central

    Ba, Yue; Huang, Huang; Lerro, Catherine C.; Li, Shuzhen; Zhao, Nan; Li, Anqi; Ma, Shuangge; Udelsman, Robert; Zhang, Yawei

    2016-01-01

    Objective The study aims to explore the associations between various occupations and thyroid cancer risk. Methods A population-based case-control study involving 462 histologically confirmed incident cases and 498 controls was conducted in Connecticut in 2010–2011. Results A significantly increased risk of thyroid cancer, particularly papillary microcarcinoma, was observed for those working as the healthcare practitioners and technical workers, health diagnosing and treating practitioners and registered nurses. Those working in building and grounds cleaning, maintenance occupations, pest control, retail sales, and customer service also had increased risk for papillary thyroid cancer. Subjects who worked as cooks, janitors, cleaners, and customer service representatives were at an increased risk of papillary thyroid cancer with tumor size >1 cm. Conclusions Certain occupations were associated with an increased risk of thyroid cancer, with some tumor size and subtype specificity. PMID:26949881

  5. Causative or precipitating aspects of burning mouth syndrome: a case-control study.

    PubMed

    Sardella, Andrea; Lodi, Giovanni; Demarosi, Federica; Uglietti, Daniela; Carrassi, Antonio

    2006-09-01

    On causative or precipitating causes of burning mouth syndrome (BMS), there is a lack of consensus. In this prospective case-control study, we compared clinical features and laboratory aspects to evaluate the association of the proposed causative/precipitating factors of BMS. A total of 61 BMS patients and 54 control subjects underwent several evaluations: rest and stimulated salivary flow rates measurements, laboratory tests, isolation of Candida species, assessment of parafunctional activities, detection of anxiety and depression by means of the Hospital Anxiety and Depression Scale. Odds ratio and 95% confidence interval were calculated to compare the variables. No statistically significant differences were found with regard to the tested variables except for anxiety and depression. The results of this study seem not to support a role for the usually reported causative or precipitating factors of BMS and efforts should be addressed towards different aetiologies including possible neuropathic mechanisms of BMS.

  6. A case-control study of pediatric falls using electronic medical records.

    PubMed

    Messmer, Patricia Ruth; Williams, Phoebe D; Williams, Arthur R

    2013-01-01

    The purpose of this study was to retrospectively review Humpty Dumpty Falls Scale (HDFS) scores using electronic medical records (EMR) reports at a pediatric hospital to determine characteristics related to falls, injuries, and performance of the HDFS tool. The specific research question was: Is there a significant difference in HDFS total scores between cases (children who fell) and controls (those who did not fall)? Results from 74 cases and 242 controls revealed the number of falls did not differ significantly between those who obtained high HDFS scores and those who obtained low scores. HDFS sensitivity was 57%, specificity was 39%. The pediatric patients who fell were mostly oriented and ambulating; falls with injury did not exceed 19%. Future case-control studies should use larger sample sizes across multiple institutions with EMR capability. © 2013 Association of Rehabilitation Nurses.

  7. Point source modeling of matched case-control data with multiple disease subtypes.

    PubMed

    Li, Shi; Mukherjee, Bhramar; Batterman, Stuart

    2012-12-10

    In this paper, we propose nonlinear distance-odds models investigating elevated odds around point sources of exposure, under a matched case-control design where there are subtypes within cases. We consider models analogous to the polychotomous logit models and adjacent-category logit models for categorical outcomes and extend them to the nonlinear distance-odds context. We consider multiple point sources as well as covariate adjustments. We evaluate maximum likelihood, profile likelihood, iteratively reweighted least squares, and a hierarchical Bayesian approach using Markov chain Monte Carlo techniques under these distance-odds models. We compare these methods using an extensive simulation study and show that with multiple parameters and a nonlinear model, Bayesian methods have advantages in terms of estimation stability, precision, and interpretation. We illustrate the methods by analyzing Medicaid claims data corresponding to the pediatric asthma population in Detroit, Michigan, from 2004 to 2006.

  8. Food groups and endometrial cancer risk: a case-control study from Italy.

    PubMed

    Bravi, Francesca; Scotti, Lorenza; Bosetti, Cristina; Zucchetto, Antonella; Talamini, Renato; Montella, Maurizio; Greggi, Stefano; Pelucchi, Claudio; Negri, Eva; Franceschi, Silvia; La Vecchia, Carlo

    2009-03-01

    Although several studies have been conducted on the relation between dietary habits and endometrial cancer risk, the evidence for specific food groups is still controversial. We analyzed data from an Italian case-control study including 454 women with histologically confirmed endometrial cancer and 908 controls admitted to the same hospitals for acute, nonneoplastic conditions. Multivariate odds ratios (ORs) were obtained after allowance for major potential confounding factors. A significant increase in risk was observed for red meat, with an OR of 2.07 for an increment of 1 serving per day. Inverse associations were observed for coffee (OR, 0.83), cereals (OR, 0.92), and vegetables (OR, 0.83). Our results support the existence of a relation between dietary habits and endometrial cancer risk and in particular suggest that a diet rich in red meat and poor in vegetables may have an unfavorable effect.

  9. A nested case control study of lung cancer among New York talc workers.

    PubMed

    Gamble, J F

    1993-01-01

    This nested case control study assessed the relationship of lung cancer and time exposed to talc, while controlling for smoking, other talc exposures, and nontalc exposures. There were 22 lung cancer cases (91% smokers and 9% former smokers) and 66 controls (27% nonsmokers, 9% former smokers, and 64% smokers). Smokers were at sixfold increased risk compared to nonsmokers and ex-smokers. When stratified by smoking status, risk of lung cancer decreased with talc tenure and remained negative when excluding cases with < 20 years' latency and short-term workers. These data suggest that nontalc exposures are not confounding risk factors while smoking is, and that temporal and exposure-response relationships are consistent with a smoking etiology but not an occupational etiology for lung cancer.

  10. Fresh water swimming as a risk factor for otitis externa: a case-control study.

    PubMed

    Springer, G L; Shapiro, E D

    1985-01-01

    A case-control study was conducted in which the amount and sites (fresh-water lakes and rivers, chlorinated pools, or the ocean) of recent swimming by 105 patients with otitis externa were compared with that of 239 controls. Swimming during the week prior to the visit was strongly associated with otitis externa. When the 80 cases and 127 controls with a history of recent swimming were compared, otitis externa was positively associated with the amount of swimming during the preceding week. Otitis externa was also positively associated with swimming in fresh water compared with ocean or pool swimming with the magnitude of this association being more pronounced at higher levels of exposure.

  11. Squamous cell carcinoma in plantar ulcers in leprosy. A case control study.

    PubMed

    Richardus, J H; Smith, T C

    1993-09-01

    The objective of this case-control study was to identify factors associated with the development of squamous cell carcinoma (SCC) in plantar ulcers of leprosy patients. We examined 2 matched groups consisting of leprosy patients with and without SCC in a plantar ulcer. No correlations were found between the development of SCC and race, profession, place of origin, duration of leprosy, the type and duration of leprosy chemotherapy, presence of bone involvement and type of ulcer care treatment given. The only statistically valid finding was that the duration of the ulcer was significantly lower in the group with malignant change. In this group there was an apparently higher use of pesticides, the difference being not of statistical significance. It is concluded that factors other than ulcer duration need to be looked for, in order to identify factors influencing malignant change in plantar ulcers of leprosy patients.

  12. Incidence of basilar invagination in patients with tonsillar herniation? A case control craniometrical study.

    PubMed

    Joaquim, Andrei F; Fernandes, Yvens Barbosa; Mathias, Roger N; Batista, Ulysses C; Ghizoni, Enrico; Tedeschi, Helder; Patel, Alpesh A

    2014-09-01

    A retrospective case-control study based on craniometrical evaluation was performed to evaluate the incidence of basilar invagination (BI). Patients with symptomatic tonsillar herniation treated surgically had craniometrical parameters evaluated based on CT scan reconstructions before surgery. BI was diagnosed when the tip of the odontoid trespassed the Chamberlain's line in three different thresholds found in the literature: 2, 5 or 6.6 mm. In the surgical group (SU), the mean distance of the tip of the odontoid process above the Chamberlain's line was 12 mm versus 1.2 mm in the control (CO) group (p<0.0001). The number of patients with BI according to the threshold used (2, 5 or 6.6 mm) in the SU group was respectively 19 (95%), 16 (80%) and 15 (75%) and in the CO group it was 15 (37%), 4 (10%) and 2 (5%).

  13. 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.

  14. Case-control studies of sporadic cryptosporidiosis in Melbourne and Adelaide, Australia.

    PubMed Central

    Robertson, B.; Sinclair, M. I.; Forbes, A. B.; Veitch, M.; Kirk, M.; Cunliffe, D.; Willis, J.; Fairley, C. K.

    2002-01-01

    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. PMID:12113486

  15. Bladder cancer in Massachusetts related to chlorinated and chloraminated drinking water: a case-control study

    SciTech Connect

    Zierler, S.; Feingold, L.; Danley, R.A.; Craun, G.

    1988-03-01

    Consumers of chlorinated drinking water have a small excess of bladder cancer. Risk may have been underestimated because of confounding and misclassification of exposure status. To address these problems, we undertook a case-control study. Detailed residential histories were obtained by telephone interviews with informants of 614 individuals who died of primarily bladder cancer and 1,074 individuals who died of other causes. Their surface water has been disinfected with chlorine or a combination of chlorine and ammonia (cloramine) since 1938. The mortality ratio for bladder cancer among individuals who resided only in communities supplied with drinking water disinfected with chlorine, relative to individuals who resided only in communities supplied with drinking water disinfected with chloramine, was 1.6 (95% confidence interval = 1.2-2.1), using all controls; when the comparison group was restricted to individuals who died of lymphoma, the mortality odds ratio was 2.7 (95% confidence interval = 1.7-4.3).

  16. Bladder cancer in Massachusetts related to chlorinated and chloraminated drinking water: a case-control study.

    PubMed

    Zierler, S; Feingold, L; Danley, R A; Craun, G

    1988-01-01

    Consumers of chlorinated drinking water have a small excess of bladder cancer. Risk may have been underestimated because of confounding and misclassification of exposure status. To address these problems, we undertook a case-control study. Detailed residential histories were obtained by telephone interviews with informants of 614 individuals who died of primarily bladder cancer and 1,074 individuals who died of other causes. Their surface water has been disinfected with chlorine or a combination of chlorine and ammonia (cloramine) since 1938. The mortality ratio for bladder cancer among individuals who resided only in communities supplied with drinking water disinfected with chlorine, relative to individuals who resided only in communities supplied with drinking water disinfected with chloramine, was 1.6 (95% confidence interval = 1.2-2.1), using all controls; when the comparison group was restricted to individuals who died of lymphoma, the mortality odds ratio was 2.7 (95% confidence interval = 1.7-4.3).

  17. A case-control study of Salmonella gastrointestinal infection in Italian children.

    PubMed

    Borgnolo, G; Barbone, F; Scornavacca, G; Franco, D; Vinci, A; Iuculano, F

    1996-07-01

    A case-control study of 85 cases with non-typhoid Salmonella gastroenteritis, 85 outpatient controls and 79 inpatient controls was conducted among children in Monfalcone, north-east Italy, between June 1989 and June 1994. Logistic regression was used to evaluate the effect of demographic and socio-economic characteristics, duration of breastfeeding, history of intestinal illnesses and household diarrhoea, and the recent use of antimicrobials. Breastfeeding was the single most important factor associated with a 5-fold decreased risk of Salmonella infection. In addition, children who were treated with antimicrobials before onset of gastroenteritis had a 3-fold increased risk. Low social class and history of other chronic non-infectious intestinal diseases were also directly associated with illness.

  18. National case-control study of homicide offending and methamphetamine use.

    PubMed

    Stretesky, Paul B

    2009-06-01

    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 main outcome measure is homicide. Results suggest that the odds of committing a homicide are nearly 9 times greater for an individual who uses methamphetamine. More importantly, the association between methamphetamine use and homicide persists even after adjusting for alternative drug use (i.e., alcohol, heroin, crack, cocaine, PCP, LSD), sex, race, income, age, marital status, previous arrests, military experience, and education level. Methamphetamine was the only drug use variable that was strongly correlated with homicide. These results support recent clinical studies that suggest methamphetamine use is different than other drug use in its effects on violence.

  19. 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.

  20. 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.

  1. 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.

  2. A case control study: White-collar defendants compared with defendants charged with other nonviolent theft.

    PubMed

    Poortinga, Ernest; Lemmen, Craig; Jibson, Michael D

    2006-01-01

    We examined the clinical, criminal, and sociodemographic characteristics of all white-collar crime defendants referred to the evaluation unit of a state center for forensic psychiatry. With 29,310 evaluations in a 12-year period, we found 70 defendants charged with embezzlement, 3 with health care fraud, and no other white-collar defendants (based on the eight crimes widely accepted as white-collar offenses). In a case-control study design, the 70 embezzlement cases were compared with 73 defendants charged with other forms of nonviolent theft. White-collar defendants were found to have a higher likelihood of white race (adjusted odds ratio (adj. OR) = 4.51), more years of education (adj. OR = 3471), and a lower likelihood of substance abuse (adj. OR = .28) than control defendants. Logistic regression modeling showed that the variance in the relationship between unipolar depression and white-collar crime was more economically accounted for by education, race, and substance abuse.

  3. Are abnormal premorbid personality traits associated with Alzheimer's disease? - A case-control study.

    PubMed

    Nicholas, Helen; Moran, Paul; Foy, Catherine; Brown, Richard G; Lovestone, Simon; Bryant, Stephanie; Boothby, Harry

    2010-04-01

    To examine the association between premorbid personality traits, social networks and AD, using a case-control design, and two informant-based retrospective assessments of premorbid personality. Cases consisted of 217 Subjects diagnosed with probable late onset Alzheimer's disease (160 females and 57 males). Recruitment was from both community and nursing home settings. Controls consisted of 76 unaffected siblings (44 females and 32 males) of patients with AD. Both cases and controls received informant ratings of premorbid personality. A selection of abnormal personality traits were over represented in the AD group. AD was particularly associated with Cluster A personality disorder traits (Paranoid, Schizoid, Schizotypal). AD cases had correspondingly sparser social networks. There is an association between abnormal personality traits and AD. Individuals with AD also appear to have had lower levels of social interactivity.

  4. "Virtual" clinical trials: case control experiments utilizing a health services research workstation.

    PubMed Central

    Weiner, M. G.; Hillman, A. L.

    1998-01-01

    We created an interface to a growing repository of clinical and administrative information to facilitate the design and execution of case-control experiments. The system enables knowledgeable users to generate and test hypotheses regarding associations among diseases and outcomes. The intuitive interface allows the user to specify criteria for selecting cases and defining putative risks. The repository contains comprehensive administrative and selected clinical information on all ambulatory and emergency department visits as well as hospital admissions since 1994. We tested the workstation's ability to determine relationships between outpatient diagnoses including hypertension, osteoarthritis and hypercholesterolemia with the occurrence of admissions for stroke and myocardial infarction and achieved results consistent with published studies. Successful implementation of this Health Services Research Workstation will allow "virtual" clinical trials to validate the results of formal clinical trials on a local population and may provide meaningful analyses of data when formal clinical trials are not feasible. PMID:9929230

  5. 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.

  6. Blinded case-control study of the relationship between human coronavirus NL63 and Kawasaki syndrome.

    PubMed

    Dominguez, Samuel R; Anderson, Marsha S; Glodé, Mary P; Robinson, Christine C; Holmes, Kathryn V

    2006-12-15

    We conducted a blinded, case-control, retrospective study in pediatric patients hospitalized at The Children's Hospital, Denver, Colorado, to determine whether human coronavirus (HCoV)-NL63 infection is associated with Kawasaki syndrome (KS). Over the course of a 7-month period, nasopharyngeal-wash samples from 2 (7.7%) of 26 consecutive children with KS and 4 (7.7%) of 52 matched control subjects tested positive for HCoV-NL63 by reverse transcription-polymerase chain reaction. These data suggest that, although HCoV-NL63 was circulating in children in our community during the time of the study, the prevalence of infection with HCoV-NL63 was not greater in patients with KS than in control subjects.

  7. On Combining Family–based and Population-based Case-control Data in Association Studies

    PubMed Central

    Zheng, Yingye; Heagerty, Patrick J.; Hsu, Li; Newcomb, Polly A

    2011-01-01

    Summary Combining data collected from different sources can potentially enhance statistical efficiency in estimating effects of environmental or genetic factors or gene-environment interactions. However, combining data across studies becomes complicated when data are collected under different study designs, such as family-based and unrelated individual-based case-control design. In this paper, we describe likelihood based approaches that permit the joint estimation of covariate effects on disease risk under study designs that include cases, relatives of cases, and unrelated individuals. Our methods accommodate familial residual correlation and a variety of ascertainment schemes. Extensive simulation experiments demonstrate that the proposed methods for estimation and inference perform well in realistic settings. Efficiencies of different designs are contrasted in the simulation. We applied the methods to data from the Colorectal Cancer Family Registry. PMID:20163402

  8. Causal diagrams and the logic of matched case-control studies

    PubMed Central

    Shahar, Eyal; Shahar, Doron J

    2012-01-01

    It is tempting to assume that confounding bias is eliminated by choosing controls that are identical to the cases on the matched confounder(s). We used causal diagrams to explain why such matching not only fails to remove confounding bias, but also adds colliding bias, and why both types of bias are removed by conditioning on the matched confounder(s). As in some publications, we trace the logic of matching to a possible tradeoff between effort and variance, not between effort and bias. Lastly, we explain why the analysis of a matched case-control study – regardless of the method of matching – is not conceptually different from that of an unmatched study. PMID:22701093

  9. Risk factors for campylobacter infection in infants and young children: a matched case-control study.

    PubMed Central

    Tenkate, T. D.; Stafford, R. J.

    2001-01-01

    Campylobacter infection has one of the highest rates of all the notifiable diseases in Australia, with a peak in children aged 0-35 months. A matched case-control study was conducted to investigate risk factors for campylobacter infection for children in this age group. Eighty-one cases and 144 controls were enrolled in the study that was conducted between 24 January 1996 and 21 January 1997. The following risk factors were found to be independently associated with illness: ownership of pet puppies (adjusted odds ratio [OR] 16.58, 95% confidence interval [CI] 3.73-73.65) and pet chickens (OR 11.80, CI 1.37-101.75), and consumption of mayonnaise (OR 4.13, CI 1.61-10.59). We propose that children aged less than 3 years are at risk of campylobacter infection if residing in a household which has puppies or chickens as pets. PMID:11811871

  10. A case-control study of Nocardia mastitis in Nova Scotia dairy herds

    PubMed Central

    Ferns, Lyn; Dohoo, Ian; Donald, Alan

    1991-01-01

    A case-control study was conducted to identify herd production, housing, and hygienic and therapeutic factors associated with a diagnosis of Nocardia mastitis in dairy herds in Nova Scotia. The data were collected by on-farm interviews with owners of 54 case and 54 control herds. Logistic regression was used to study risk factors. The use of dry cow products containing neomycin, including two specific dry cow products, was strongly associated with a diagnosis of Nocardia mastitis in a herd. Other factors which increased the risk of Nocardia mastitis were higher levels of production, larger herd size, and a large percentage of cows treated with dry cow products. These results are compared to results from a similar study carried out in Ontario. PMID:17423896

  11. The pediatric heart network: meeting the challenges to multicenter studies in pediatric heart disease

    PubMed Central

    Burns, Kristin M.; Pemberton, Victoria L.; Pearson, Gail D.

    2017-01-01

    Purpose of review Because of the relatively small numbers of pediatric patients with congenital heart disease cared for in any individual center, there is a significant need for multicenter clinical studies to validate new medical or surgical therapies. The Pediatric Heart Network (PHN), with 15 years of experience in multicenter clinical research, has tackled numerous challenges when conducting multicenter studies. Recent findings This review describes the challenges encountered and the strategies employed to conduct high-quality, collaborative research in pediatric cardiovascular disease. Summary Sharing lessons learned from the PHN can provide guidance to investigators interested in conducting pediatric multicenter studies. PMID:26196261

  12. Obesity and symptomatic cholelithiasis in childhood: epidemiologic and case-control evidence for a strong relation.

    PubMed

    Fradin, Kelly; Racine, Andrew D; Belamarich, Peter F

    2014-01-01

    The aims of this study were to correlate the temporal trends in obesity prevalence with hospitalization rates for symptomatic cholelithiasis and to estimate the strength of the association between obesity and symptomatic cholelithiasis in patients hospitalized at an urban children's hospital in New York serving a multiethnic population. Using obesity prevalence data from the National Health and Nutrition Examination Survey and the rates of hospitalization for cholelithiasis derived from the Kids' Inpatient Database for 1997-2007, we estimated a correlation and a linear regression. We conducted a retrospective, case-control study in which each case ages 4 to 20 years with symptomatic cholelithiasis was individually matched to a control admitted with appendicitis based on age, sex, ethnicity, and race. The prevalence of obesity and the cholelithiasis hospitalization rate increased over time (R=0.87, P=0.0025). For every 1% increase in the obesity rate among children, the rate of hospitalization for gallstones increased by 0.65/100,000 children (R²=0.75, P=0.0025, 95% confidence interval [CI] 0.32-0.99). The odds ratio for obesity in cases versus controls was 5.78 (n=518, P<0.0001, 95% CI 3.50-9.53). We found a significant dose-response effect, which showed that for every 1 z score increase in body mass index, the risk of cholelithiasis was increased by 79% (P<0.0001, 95% CI 1.5-2.13). The national trend in the prevalence of obesity from 1997 to 2009 was significantly correlated with increasing rates of hospitalization for pediatric cholelithiasis. Our case-control study suggests that obesity is a significant risk factor for hospital admission because of cholelithiasis.

  13. 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

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

    PubMed

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

    2016-01-01

    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. 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. 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). 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.

  15. Coffee consumption and risk of colorectal cancer: a meta-analysis of case-control studies.

    PubMed

    Galeone, Carlotta; Turati, Federica; La Vecchia, Carlo; Tavani, Alessandra

    2010-11-01

    A meta-analysis of case-control studies on coffee consumption and colorectal cancer risk was conducted. Twenty-four eligible studies published before May 2010 were identified, including a total of 14,846 cases of colorectal, colon or rectal cancer. Compared to non/occasional drinkers, the odds ratios (OR) for drinkers were 0.83 (95% CI 0.73-0.95) for colorectal, 0.93 (95% CI 0.81-1.07) for colon and 0.98 (95% CI 0.85-1.13) for rectal cancer, with significant heterogeneity among studies; the corresponding ORs for the increment of 1 cup/day were 0.94 (95% CI 0.91-0.98), 0.95 (95% CI 0.92-0.98), and 0.97 (95% CI 0.95-0.99). For the highest coffee drinkers, the ORs were 0.70 (95% CI 0.60-0.81) for colorectal cancer, 0.75 (95% CI 0.64-0.88) for colon cancer and 0.87 (95% CI 0.75-1.00) for rectal cancer, when compared to non/low drinkers. The results of this meta-analysis of case-control studies suggest a moderate favorable effect of coffee consumption on colorectal cancer risk. The reduced risk was consistent across study design (hospital vs. population based), geographic area, and various confounding factors considered. It may reflect a real protection but also partly or largely be due to reverse causation, i.e. decreased coffee consumption among cases following the onset of bowel symptoms.

  16. Exposure to electromagnetic fields and suicide among electric utility workers: a nested case-control study.

    PubMed

    van Wijngaarden, E; Savitz, D A; Kleckner, R C; Cai, J; Loomis, D

    2000-04-01

    This nested case-control study examines mortality from suicide in relation to estimated exposure to extremely low frequency electromagnetic fields (EMFs) in a cohort of 138,905 male electric utility workers. Case-control sampling included 536 deaths from suicide and 5348 eligible controls. Exposure was classified based on work in the most common jobs with increased exposure to magnetic fields and indices of cumulative exposure to magnetic fields based on a measurement survey. Suicide mortality was increased relative to work in exposed jobs and with indices of exposure to magnetic fields. Increased odds ratios (ORs) were found for years of employment as an electrician (OR 2.18; 95% confidence interval (95% CI) 1.25 to 3.80) or lineman (OR 1.59; 95% CI 1.18 to 2.14), whereas a decreased OR was found for power plant operators (OR 0.67; 95% CI 0.33 to 1.40). A dose response gradient with exposure to magnetic fields was found for exposure in the previous year, with a mortality OR of 1.70 (95% CI 1.00 to 2.90) in the highest exposure category. Stronger associations, with ORs in the range of 2.12-3.62, were found for men <50 years of age. These data provide evidence for an association between occupational electromagnetic fields and suicide that warrants further evaluation. A plausible mechanism related to melatonin and depression provides a direction for additional laboratory research as well as epidemiological evaluation.

  17. A Joint Association Test for Multiple SNPs in Genetic Case-Control Studies

    PubMed Central

    Wang, Tao; Jacob, Howard; Ghosh, Soumitra; Wang, Xujing; Zeng, Zhao-Bang

    2009-01-01

    For a dense set of genetic markers such as single nucleotide polymorphisms (SNPs) on high linkage disequilibrium within a small candidate region, a haplotype-based approach for testing association between a disease phenotype and the set of markers is attractive in reducing the data complexity and increasing the statistical power. However, due to unknown status of the underlying disease variant, a comprehensive association test may require consideration of various combinations of the SNPs, which often leads to severe multiple testing problems. In this paper, we propose a latent variable approach to test for association of multiple tightly linked SNPs in case-control studies. First, we introduce a latent variable into the penetrance model to characterize a putative disease susceptible locus (DSL) that may consist of a marker allele, a haplotype from a subset of the markers, or an allele at a putative locus between the markers. Next, through using of a retrospective likelihood to adjust for the case-control sampling ascertainment and appropriately handle the Hardy-Weinberg equilibrium constraint, we develop an expectation-maximization (EM)-based algorithm to fit the penetrance model and estimate the joint haplotype frequencies of the DSL and markers simultaneously. With the latent variable to describe a flexible role of the DSL, the likelihood ratio statistic can then provide a joint association test for the set of markers without requiring an adjustment for testing of multiple haplotypes. Our simulation results also reveal that the latent variable approach may have improved power under certain scenarios comparing with classical haplotype association methods. PMID:18770519

  18. Selective Serotonin Reuptake Inhibitors and Gastrointestinal Bleeding: A Case-Control Study

    PubMed Central

    Carvajal, Alfonso; Ortega, Sara; Del Olmo, Lourdes; Vidal, Xavier; Aguirre, Carmelo; Ruiz, Borja; Conforti, Anita; Leone, Roberto; López-Vázquez, Paula; Figueiras, Adolfo; Ibáñez, Luisa

    2011-01-01

    Background Selective serotonin reuptake inhibitors (SSRIs) have been associated with upper gastrointestinal (GI) bleeding. Given their worldwide use, even small risks account for a large number of cases. This study has been conducted with carefully collected information to further investigate the relationship between SSRIs and upper GI bleeding. Methods We conducted a case-control study in hospitals in Spain and in Italy. Cases were patients aged ≥18 years with a primary diagnosis of acute upper GI bleeding diagnosed by endoscopy; three controls were matched by sex, age, date of admission (within 3 months) and hospital among patients who were admitted for elective surgery for non-painful disorders. Exposures to SSRIs, other antidepressants and other drugs were defined as any use of these drugs in the 7 days before the day on which upper gastrointestinal bleeding started (index day). Results 581 cases of upper GI bleeding and 1358 controls were considered eligible for the study; no differences in age or sex distribution were observed between cases and controls after matching. Overall, 4.0% of the cases and 3.3% of controls used an SSRI antidepressant in the week before the index day. No significant risk of upper GI bleeding was encountered for SSRI antidepressants (adjusted odds ratio, 1.06, 95% CI, 0.57–1.96) or for whichever other grouping of antidepressants. Conclusions The results of this case-control study showed no significant increase in upper GI bleeding with SSRIs and provide good evidence that the magnitude of any increase in risk is not greater than 2. PMID:21625637

  19. Poison prevention practices and medically attended poisoning in young children: multicentre case-control study.

    PubMed

    Kendrick, Denise; Majsak-Newman, Gosia; Benford, Penny; Coupland, Carol; Timblin, Clare; Hayes, Mike; Goodenough, Trudy; Hawkins, Adrian; Reading, Richard

    2017-04-01

    Childhood poisonings are common, placing a substantial burden on health services. Case-control studies have found inconsistent evidence about modifiable risk factors for poisonings among children aged 0-4 years. This study quantifies associations between poison prevention practices and medically attended poisonings in children aged 0-4 years. Multicentre case-control study conducted at hospitals, minor injury units and family practices from four study centres in England between 2010 and 2013. Participants comprised 567 children presenting with unintentional poisoning occurring at home and 2320 community control participants matched on age, sex, date of event and study centre. Parents/caregivers provided data on safety practices, safety equipment use, home hazards and potential confounders by means of self-completion questionnaires. Data were analysed using conditional logistic regression. Compared with community controls, parents of poisoned children were significantly more likely not to store medicines out of reach (adjusted OR (AOR) 1.59; 95% CI 1.21 to 2.09; population attributable fraction (PAF) 15%), not to store medicines safely (locked or out of reach (AOR 1.83; 95% CI 1.38 to 2.42; PAF 16%) and not to have put all medicines (AOR 2.11; 95% CI 1.54 to 2.90; PAF 20%) or household products (AOR 1.79, 95% CI 1.29 to 2.48; PAF 11%) away immediately after use. Not storing medicines out of reach or locked away and not putting medicines and household products away immediately after use increased the odds of secondary care attended poisonings in children aged 0-4 years. If associations are causal, implementing these poison prevention practices could each prevent between 11% and 20% of poisonings. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  20. Healthy control subjects are poorly defined in case-control studies of irritable bowel syndrome

    PubMed Central

    Ghorbani, Shireen; Nejad, Amir; Law, David; Chua, Kathleen S.; Amichai, Meridythe M.; Pimentel, Mark

    2015-01-01

    Background Case-control studies are vital for understanding the pathophysiology of gastrointestinal disease. While the definition of disease is clear, the definition of healthy control is not. This is particularly relevant for functional bowel diseases such as irritable bowel syndrome (IBS). In this study, a systematic review formed the basis for a prospective study evaluating the effectiveness of commonly used techniques for defining healthy controls in IBS. Methods A systematic review of the literature was conducted to identify case-control studies involving functional gastrointestinal disorders. “Lack of Rome criteria”, self-description as “healthy” and the bowel disease questionnaire (BDQ) were common methods for identifying healthy controls. These 3 methods were then applied to a cohort of 53 non-patient subjects to determine their validity compared to objective outcome measures (7-day stool diary). Results “Lack of Rome criteria” and “healthy” self-description were the most common methods for identifying healthy control subjects, but many studies failed to describe the methods used. In the prospective study, more subjects were identified as non-healthy using the BDQ than using either lack of Rome criteria (P=0.01) or “healthy” self-description (P=0.026). Furthermore, stool diaries identified several subjects with abnormal stool form and/or frequency which were not identified using lack of Rome criteria or the “healthy” question. Comparisons revealed no agreement (κ) between the different methods for defining healthy controls. Conclusions The definitions of healthy controls in studies of functional bowel diseases such as IBS are inconsistent. Since functional symptoms are common, a strict definition of “normal” is needed in this area of research. PMID:25609236

  1. Risk factors for mortality in ventilator-associated tracheobronchitis: a case-control study

    PubMed Central

    Pontes, Leonilda Giani; de Menezes, Fernando Gatti; Gonçalves, Priscila; Toniolo, Alexandra do Rosário; Silva, Claudia Vallone; Kawagoe, Julia Yaeko; dos Santos, Camila Marques; Castagna, Helena Maria Fernandes; Martino, Marinês Dalla Valle; Corrêa, Luci

    2017-01-01

    ABSTRACT Objective To describe the microbiological characteristics and to assess the risk factors for mortality of ventilator-associated tracheobronchitis in a case-control study of intensive care patients. Methods This case-control study was conducted over a 6-year period in a 40-bed medical-surgical intensive care unit in a tertiary care, private hospital in São Paulo, Brazil. Case patients were identified using the Nosocomial Infection Control Committee database. For the analysis of risk factors, matched control subjects were selected from the same institution at a 1:8.8 ratio, between January 2006 and December 2011. Results A total of 40 episodes of ventilator-associated tracheobronchitis were evaluated in 40 patients in the intensive care unit, and 354 intensive care patients who did not experience tracheobronchitis were included as the Control Group. During the 6-year study period, a total of 42 organisms were identified (polymicrobial infections were 5%) and 88.2% of all the microorganisms identified were Gram-negative. Using a logistic regression model, we found the following independent risk factors for mortality in ventilator-associated tracheobronchitis patients: Acute Physiology and Chronic Health Evaluation I score (odds ratio 1.18 per unit of score; 95%CI: 1.05-1.38; p=0.01), and duration of mechanical ventilation (odds ratio 1.09 per day of mechanical ventilation; 95%CI: 1.03-1.17; p=0.004). Conclusion Our study provided insight into the risk factors for mortality and microbiological characteristics of ventilator-associated tracheobronchitis. PMID:28444091

  2. Benzodiazepines and hip fractures in elderly people: case-control study

    PubMed Central

    Pierfitte, Corinne; Macouillard, Gerard; Thicoïpe, Michel; Chaslerie, Anicet; Pehourcq, Fabienne; Aïssou, Myriam; Martinez, Béatrice; Lagnaoui, Rajaa; Fourrier, Annie; Bégaud, Bernard; Dangoumau, Jacques; Moore, Nicholas

    2001-01-01

    Objective To determine whether benzodiazepines are associated with an increased risk of hip fracture. Design Case-control study. Participants All incident cases of hip fracture not related to traffic accidents or cancer in patients over 65 years of age. 245 cases were matched to 817 controls. Setting Emergency department of a university hospital. Main outcome measures Exposure to benzodiazepines and other potential risk or protective factors or lifestyle items. Results The use of benzodiazepines as determined from questionnaires, medical records, or plasma samples at admission to hospital was not associated with an increased risk of hip fracture (odds ratio 0.9, 95% confidence interval 0.5 to 1.5). Hip fracture was, however, associated with the use of two or more benzodiazepines, as determined from questionnaires or medical records but not from plasma samples. Of the individual drugs, only lorazepam was significantly associated with an increased risk of hip fracture (1.8, 1.1 to 3.1). Conclusion Except for lorazepam, the presence of benzodiazepines in plasma was not associated with an increased risk of hip fracture. The method used to ascertain exposure could influence the results of case-control studies. What is already known on this topicBenzodiazepines increase the risk of elderly people falling in a dose dependent wayTheir role in hip fracture remains disputed, with increased risk sometimes attributed to drugs with a longer half life or those used to induce sleepWhat this study addsBenzodiazepines were not associated with hip fracture either as a group or according to half life or to characterisation as hypnotic or anxiolyticPatients using two or more benzodiazepines may be at higher riskPatients using lorazepam or certain other benzodiazepines may also be at a higher risk of fracture PMID:11264208

  3. Neurocognitive performance in family-based and case-control studies of schizophrenia

    PubMed Central

    Gur, Ruben C.; Braff, David L.; Calkins, Monica E.; Dobie, Dorcas J.; Freedman, Robert; Green, Michael F.; Greenwood, Tiffany A.; Lazzeroni, Laura C.; Light, Gregory A.; Nuechterlein, Keith H.; Olincy, Ann; Radant, Allen D.; Seidman, Larry J.; Siever, Larry J.; Silverman, Jeremy M.; Sprock, Joyce; Stone, William S.; Sugar, Catherine A.; Swerdlow, Neal R.; Tsuang, Debby W.; Tsuang, Ming T.; Turetsky, Bruce I.; Gur, Raquel E.

    2014-01-01

    Background Neurocognitive deficits in schizophrenia (SZ) are established and the Consortium on the Genetics of Schizophrenia (COGS) investigated such measures as endophenotypes in family-based (COGS-1) and case-control (COGS-2) studies. By requiring family participation, family-based sampling may result in samples that vary demographically and perform better on neurocognitive measures. Methods The Penn computerized neurocognitive battery (CNB) evaluates accuracy and speed of performance for several domains and was administered across sites in COGS-1 and COGS-2. Most tests were included in both studies. COGS-1 included 328 patients with SZ and 497 healthy comparison subjects (HCS) and COGS-2 included 1195 patients and 1009 HCS. Results Demographically, COGS-1 participants were younger, more educated, with more educated parents and higher estimated IQ compared to COGS-2 participants. After controlling for demographics, the two samples produced very similar performance profiles compared to their respective controls. As expected, performance was better and with smaller effect sizes compared to controls in COGS-1 relative to COGS-2. Better performance was most pronounced for spatial processing while emotion identification had large effect sizes for both accuracy and speed in both samples. Performance was positively correlated with functioning and negatively with negative and positive symptoms in both samples, but correlations were attenuated in COGS-2, especially with positive symptoms. Conclusions Patients ascertained through family-based design have more favorable demographics and better performance on some neurocognitive domains. Thus, studies that use case-control ascertainment may tap into populations with more severe forms of illness that are exposed to less favorable factors compared to those ascertained with family-based designs. PMID:25432636

  4. Case-control admixture mapping in Latino populations enriches for known asthma-associated genes

    PubMed Central

    Torgerson, Dara G.; Gignoux, Christopher R.; Galanter, Joshua M.; Drake, Katherine A.; Roth, Lindsey A.; Eng, Celeste; Huntsman, Scott; Torres, Raul; Avila, Pedro C.; Chapela, Rocio; Ford, Jean G.; Rodríguez-Santana, José R.; Rodríguez-Cintrón, William; Hernandez, Ryan D.; Burchard, Esteban G.

    2012-01-01

    Background Polymorphisms in more than 100 genes have been associated with asthma susceptibility, yet much of the heritability remains to be explained. Asthma disproportionately affects different racial and ethnic groups in the United States, suggesting that admixture mapping is a useful strategy to identify novel asthma-associated loci. Objective We sought to identify novel asthma-associated loci in Latino populations using case-control admixture mapping. Methods We performed genome-wide admixture mapping by comparing levels of local Native American, European, and African ancestry between children with asthma and nonasthmatic control subjects in Puerto Rican and Mexican populations. Within candidate peaks, we performed allelic tests of association, controlling for differences in local ancestry. Results Between the 2 populations, we identified a total of 62 admixture mapping peaks at a P value of less than 10−3 that were significantly enriched for previously identified asthma-associated genes (P = .0051). One of the peaks was statistically significant based on 100 permutations in the Mexican sample (6q15); however, it was not significant in Puerto Rican subjects. Another peak was identified at nominal significance in both populations (8q12); however, the association was observed with different ancestries. Conclusion Case-control admixture mapping is a promising strategy for identifying novel asthma-associated loci in Latino populations and implicates genetic variation at 6q15 and 8q12 regions with asthma susceptibility. This approach might be useful for identifying regions that contribute to both shared and population-specific differences in asthma susceptibility. PMID:22502797

  5. Association between Myocardial Infarction and Periodontitis: A Meta-Analysis of Case-Control Studies.

    PubMed

    Shi, Quan; Zhang, Bin; Huo, Na; Cai, Chuan; Liu, Hongchen; Xu, Juan

    2016-01-01

    Background and Objective: Many clinical researches have been carried out to investigate the relationship between myocardial infarction (MI) and periodontitis. Despite most of them indicated that the periodontitis may be associated with an increased risk of MI, the findings and study types of these studies have been inconsistent. The goal of this meta-analysis was to critically assess the strength of the association between MI and periodontitis in case-control studies. Methods: PubMed and the Cochrane Library were searched for eligible case-control studies reporting relevant parameters that compared periodontal status between MI and control subjects. The odds ratios (ORs) and 95% confidence intervals (CIs) from each study were pooled to estimate the strength of the association between MI and periodontitis. The mean differences and 95% CIs for periodontal-related parameters were calculated to determine their overall effects. Results: Seventeen studies including a total of 3456 MI patients and 3875 non-MI control subjects were included. The pooled OR for the association between MI and periodontitis was 2.531 (95% CI: 1.927-3.324). The mean differences (95% CIs) for clinical attachment loss, probing depth, bleeding on probing, plaque index, and the number of missing teeth were 1.000 (0.726-1.247), 1.209 (0.538-1.880), 0.342 (0.129-0.555), 0.383 (0.205-0.560), and 4.122 (2.012-6.232), respectively. Conclusion: With the current evidence, the results support the presence of a significant association between MI and periodontitis. Moreover, MI patients had worse periodontal and oral hygiene status and fewer teeth than did control subjects. More high-quality and well-designed studies focusing on the casual relationship between MI and periodontitis should be conducted in the future.

  6. 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.

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

    PubMed Central

    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. PMID:26193371

  8. Unprovoked seizures after traumatic brain injury: A population-based case-control study.

    PubMed

    Mahler, Benno; Carlsson, Sofia; Andersson, Tomas; Adelöw, Cecilia; Ahlbom, Anders; Tomson, Torbjörn

    2015-09-01

    To quantify the risk of unprovoked seizures after traumatic brain injury (TBI) METHODS: We used the Stockholm Incidence Registry on Epilepsy to carry out a population-based case-control study, including 1,885 cases with incident unprovoked seizures from September 1, 2000 through August 31, 2008, together with 15,080 matched controls. Information of prior hospitalizations for TBI was obtained through record linkage with the Swedish National Inpatient Registry for the period 1980-2008. Relative risks (RRs) for unprovoked seizures were estimated after various TBI diagnoses, and influences of TBI severity and time since trauma were studied in detail. After hospitalization for mild TBI, the RR was 2.0 (95% confidence interval [CI] 1.5-2.7). The RR was higher after brain contusion (5.9, 95% CI 2.4-15.0) or intracranial hemorrhage (ICH) (4.5, 95% CI 2.2-9.0), whereas a combination of both diagnoses led to a further sevenfold increase in RR (42.6, 95% CI 12.2-148.5). The risk was greatest during the first 6 months after severe TBI (RR 48.9, 95% CI 10.9-218.9) or mild TBI (RR 8.1, 95% CI 3.1-21.7), but was still elevated >10 years after any TBI. Herein we present a large population-based case-control study on TBI as a risk factor for unprovoked epileptic seizures, including cases of all ages with individually validated seizure diagnoses. The risk for epileptic seizures was substantially increased after TBI, especially during the first 6 months after the injury and in patients with a combination of ICH and brain contusion. Wiley Periodicals, Inc. © 2015 International League Against Epilepsy.

  9. Bone fractures and hypoglycemic treatment in type 2 diabetic patients: a case-control study.

    PubMed

    Monami, Matteo; Cresci, Barbara; Colombini, Angela; Pala, Laura; Balzi, Daniela; Gori, Francesca; Chiasserini, Veronica; Marchionni, Niccolò; Rotella, Carlo Maria; Mannucci, Edoardo

    2008-02-01

    Hypoglycemic treatments could modulate the risk for fractures in many ways. Most studies have not explored the effect on the incidence of bone fractures of individual oral hypoglycemic agents, rather all oral treatments as a whole. The aim of this case-control study, nested within a retrospective cohort, is the assessment of the risk for bone fractures associated with exposure to insulin or different oral hypoglycemic agents. A case-control study nested within a cohort of 1,945 diabetic outpatients with a follow-up of 4.1 +/- 2.3 years was performed, comparing 83 case subjects of bone fractures and 249 control subjects matched for age, sex, duration of diabetes, BMI, A1C, comorbidity, smoking, and alcohol abuse. Exposure to hypoglycemic drugs during the 10 years preceding the event (or matching index date) was assessed. In a model including treatment with insulin secretagogues metformin and insulin for at least 36 months during the previous 10 years, no significant association was observed between bone fractures and medications. In an alternative model considering treatments at the time of fracture, insulin treatment was significantly associated with bone fractures in men (OR 3.20 [95% CI 1.32-7.74]) but not in women (1.41 [0.73-2.73]). Insulin-sensitizing treatment with metformin is not associated with a higher incidence of bone fractures, suggesting that the negative effect of thiazolidinediones is due to a specific action on bone metabolism rather a reduction of insulinemia. Conversely, current treatment with insulin increases the risk of fractures; at the same time, exposure to this agent in the longer term does not appear to affect bone frailty.

  10. Endometriosis after Laparoscopic Supracervical Hysterectomy with Uterine Morcellation: A Case Control Study

    PubMed Central

    Schuster, Mitchell W.; Wheeler, Thomas L.; Richter, Holly E.

    2011-01-01

    Study Objective To compare the incidence of new onset endometriosis after laparoscopic supracervical hysterectomy (LSH) with uterine morcellation to traditional routes. Design Single center case-control study Design Classification Canadian Task Force Classification II-2 Setting Single Center case-control study of hysterectomies from January, 2006 through December, 2008. Patients 277 laparoscopic supracervical hysterectomies with morcellation (cases) and 187 transvaginal or abdominal hysterectomies without morcellation (controls) performed from January, 2006 to December 2008. Interventions 464 women underwent hysterectomy, 277 cases via laparoscopic supracervical approach (LSH) with morcellation and 187 performed either transvaginally or abdominally without morcellation. Repeat operative procedures were performed for other benign indications on 16 of 464 (3.5%) prior hysterectomy patients. Measurements and Main Results 102 patients had endometriosis at the time of hysterectomy diagnosed by pathologic evaluation or gross visualization. In those without endometriosis, repeat operative procedures were performed for pain and bleeding in 3.3% (12/362). 60% (3/5) of LSH patients and 28.6% (2/7) of the control group were found to have newly diagnosed endometriosis conferring a rate of 1.4% (3/217) for the LSH group and 1.4% (2/145) in the controls. In patients with endometriosis, repeat operative procedures for pain and/or bleeding occurred in 2.9% (3/102); 3/60 of LSH patients and none in the control group (0/42). Two of these 3 patients undergoing a second surgery had recurrent/continued endometriosis. Conclusion Newly diagnosed endometriosis was noted in 1.4% of patients after hysterectomy with a similar incidence between the LSH and control groups. Reoperation for those with endometriosis at the time of LSH with morcellation was infrequent, but endometriosis was usually found. Further research is needed to delineate risk factors for development of de novo endometriosis

  11. Risk Factors for Surgical Site Infections Following Neurosurgical Spinal Fusion Operations: A Case Control Study.

    PubMed

    Walsh, Thomas L; Querry, Ashley M; McCool, Sheila; Galdys, Alison L; Shutt, Kathleen A; Saul, Melissa I; Muto, Carlene A

    2017-03-01

    OBJECTIVE To determine risk factors for the development of surgical site infections (SSIs) in neurosurgery patients undergoing spinal fusion. DESIGN Retrospective case-control study. SETTING Large, academic, quaternary care center. PATIENTS The study population included all neurosurgery patients who underwent spinal fusion between August 1, 2009, and August 31, 2013. Cases were defined as patients in the study cohort who developed an SSI. Controls were patients in the study cohort who did not develop an SSI. METHODS To achieve 80% power with an ability to detect an odds ratio (OR) of 2, we performed an unmatched case-control study with equal numbers of cases and controls. RESULTS During the study period, 5,473 spinal fusion procedures were performed by neurosurgeons in our hospital. With 161 SSIs recorded during the study period, the incidence of SSIs associated with these procedures was 2.94%. While anterior surgical approach was found to be a protective factor (OR, 0.20; 95% confidence interval [CI], 0.08-0.52), duration of procedure (OR, 1.58; 95% CI, 1.29-1.93), American Society of Anesthesiologists score of 3 or 4 (OR, 1.79; 95% CI, 1.00-3.18), and hospitalization within the prior 30 days (OR, 5.8; 95% CI, 1.37-24.57) were found in multivariate analysis to be independent predictors of SSI following spinal fusion. Prior methicillin-resistant Staphylococcus aureus (MRSA) nares colonization was highly associated with odds 20 times higher of SSI following spinal fusion (OR, 20.30; 95% CI, 4.64-8.78). CONCLUSIONS In additional to nonmodifiable risk factors, prior colonization with MRSA is a modifiable risk factor very strongly associated with development of SSI following spinal fusion. Infect Control Hosp Epidemiol 2017;38:348-352.

  12. Statin use and risk of endometrial cancer: a nationwide registry-based case-control study.

    PubMed

    Sperling, Cecilie D; Verdoodt, Freija; Friis, Søren; Dehlendorff, Christian; Kjaer, Susanne K

    2017-02-01

    Laboratory and epidemiological evidence have suggested that statin use may protect against the development of certain cancers, including endometrial cancer. In a nationwide registry-based case-control study, we examined the association between statin use and risk of endometrial cancer. Cases were female residents of Denmark with a primary diagnosis of endometrial cancer during 2000-2009. For each case, we selected 15 female population controls matched on date of birth (±one month) using risk-set sampling. Ever use of statin was defined as two or more prescriptions on separate dates. Conditional logistic regressions were used to estimate age-matched (by design) and multivariable-adjusted odds ratios (ORs) and 95% confidence intervals (CI) for endometrial cancer associated with statin use. The multivariable-adjusted models included parity, hormone replacement therapy (HRT), obesity, diabetes, chronic obstructive pulmonary disease and education. We evaluated whether the association between statin use and endometrial cancer varied with duration and intensity of statin use, type of endometrial cancer or patient characteristics. The study population comprised 5382 endometrial cancer cases and 72 127 population controls. We observed no association between ever use of statins and endometrial cancer risk (OR 1.03, 95% CI 0.94-1.14). In addition, endometrial cancer risk did not vary substantially with duration or intensity of statin use. Stratification by type of endometrial cancer also yielded neutral ORs. In our nationwide case-control study, we found no association between statin use and risk of endometrial cancer. © 2016 Nordic Federation of Societies of Obstetrics and Gynecology.

  13. Multilocus genetic risk score associates with ischemic stroke in case-control and prospective cohort studies.

    PubMed

    Malik, Rainer; Bevan, Steve; Nalls, Michael A; Holliday, Elizabeth G; Devan, William J; Cheng, Yu-Ching; Ibrahim-Verbaas, Carla A; Verhaaren, Benjamin F J; Bis, Joshua C; Joon, Aron Y; de Stefano, Anita L; Fornage, Myriam; Psaty, Bruce M; Ikram, M Arfan; Launer, Lenore J; van Duijn, Cornelia M; Sharma, Pankaj; Mitchell, Braxton D; Rosand, Jonathan; Meschia, James F; Levi, Christopher; Rothwell, Peter M; Sudlow, Cathie; Markus, Hugh S; Seshadri, Sudha; Dichgans, Martin

    2014-02-01

    Genome-wide association studies have revealed multiple common variants associated with known risk factors for ischemic stroke (IS). However, their aggregate effect on risk is uncertain. We aimed to generate a multilocus genetic risk score (GRS) for IS based on genome-wide association studies data from clinical-based samples and to establish its external validity in prospective population-based cohorts. Three thousand five hundred forty-eight clinic-based IS cases and 6399 controls from the Wellcome Trust Case Control Consortium 2 were used for derivation of the GRS. Subjects from the METASTROKE consortium served as a replication sample. The validation sample consisted of 22 751 participants from the Cohorts for Heart and Aging Research in Genomic Epidemiology consortium. We selected variants that had reached genome-wide significance in previous association studies on established risk factors for IS. A combined GRS for atrial fibrillation, coronary artery disease, hypertension, and systolic blood pressure significantly associated with IS both in the case-control samples and in the prospective population-based studies. Subjects in the top quintile of the combined GRS had >2-fold increased risk of IS compared with subjects in the lowest quintile. Addition of the combined GRS to a simple model based on sex significantly improved the prediction of IS in the combined clinic-based samples but not in the population-based studies, and there was no significant improvement in net reclassification. A multilocus GRS based on common variants for established cardiovascular risk factors was significantly associated with IS both in clinic-based samples and in the general population. However, the improvement in clinical risk prediction was found to be small.

  14. Sympathetic skin response in multiple sclerosis: a meta-analysis of case-control studies.

    PubMed

    Margaritella, Nicolò; Mendozzi, Laura; Garegnani, Massimo; Gilardi, Elisabetta; Nemni, Raffaello; Pugnetti, Luigi

    2017-09-29

    The usefulness of sympathetic skin responses (SSR) in multiple sclerosis (MS) has been advocated by several studies in the last 20 years; however, due to a great heterogeneity of findings, a comprehensive meta-analysis of case-control studies is in order to pinpoint consistencies and investigate the causes of discrepancies. We searched MEDLINE, EMBASE and Cochrane databases for case-control studies comparing SSR absence frequency and latency between patients with MS and healthy controls. Thirteen eligible studies including 415 MS patients and 331 healthy controls were identified. The pooled analysis showed that SSR can be always obtained in healthy controls while 34% of patients had absent SSRs in at least one limb (95% CI 22-47%; p < 0.0001) but with considerable heterogeneity across studies (I (2) = 90.3%). Patients' age explained 22% of the overall variability and positive correlations were found with Expanded Disability Status Scale and disease duration. The pooled mean difference of SSR latency showed a significant increase in patients on both upper (193 ms; 95% CI 120-270 ms) and lower (350 ms; 95% CI 190-510 ms) extremities. We tested the discriminatory value of SSR latency thresholds defined as the 95% confidence interval (CI) upper bound of the healthy controls, and validated the results on a new dataset. The lower limb threshold of 1.964 s produces the best results in terms of sensitivity 0.86, specificity 0.67, positive predicted value 0.75 and negative predicted value 0.80. Despite a considerable heterogeneity of findings, there is evidence that SSR is a useful tool in MS.

  15. Validity of using ad hoc methods to analyze secondary traits in case-control association studies.

    PubMed

    Yung, Godwin; Lin, Xihong

    2016-12-01

    Case-control association studies often collect from their subjects information on secondary phenotypes. Reusing the data and studying the association between genes and secondary phenotypes provide an attractive and cost-effective approach that can lead to discovery of new genetic associations. A number of approaches have been proposed, including simple and computationally efficient ad hoc methods that ignore ascertainment or stratify on case-control status. Justification for these approaches relies on the assumption of no covariates and the correct specification of the primary disease model as a logistic model. Both might not be true in practice, for example, in the presence of population stratification or the primary disease model following a probit model. In this paper, we investigate the validity of ad hoc methods in the presence of covariates and possible disease model misspecification. We show that in taking an ad hoc approach, it may be desirable to include covariates that affect the primary disease in the secondary phenotype model, even though these covariates are not necessarily associated with the secondary phenotype. We also show that when the disease is rare, ad hoc methods can lead to severely biased estimation and inference if the true disease model follows a probit model instead of a logistic model. Our results are justified theoretically and via simulations. Applied to real data analysis of genetic associations with cigarette smoking, ad hoc methods collectively identified as highly significant (P<10-5) single nucleotide polymorphisms from over 10 genes, genes that were identified in previous studies of smoking cessation. © 2016 WILEY PERIODICALS, INC.

  16. Noninvasive ventilation by helmet or face mask in immunocompromised patients: a case-control study.

    PubMed

    Rocco, Monica; Dell'Utri, Donatella; Morelli, Andrea; Spadetta, Gustavo; Conti, Giorgio; Antonelli, Massimo; Pietropaoli, Paolo

    2004-11-01

    To compare the efficacy of noninvasive positive pressure ventilation (NPPV) by helmet and face mask in immunocompromised patients with hypoxemic acute respiratory failure (ARF). Case-control study. The general ICU of a university hospital. Nineteen immunocompromised patients (hematologic malignancies [n = 8], solid-organ recipients [n = 8], AIDS [n = 3]) with hypoxemic ARF, fever, and lung infiltrates were treated with NPPV delivered by a helmet. Nineteen immunocompromised patients matched for diagnosis, age, simplified acute physiology score II, and Pao(2)/fraction of inspired oxygen (Fio(2)) receiving NPPV through a facial mask served as case-control subjects. The use of NPPV delivered via helmet was as effective as NPPV delivered via face mask in avoiding endotracheal intubations (intubation rate, 37% vs 47%, respectively; p = 0.37) and improving gas exchange; 14 patients (74%) in the helmet group showed a sustained improvement in Pao(2)/Fio(2) ratio (ability to increase Pao(2)/Fio(2) ratio > 200, or an increase > 100 from the baseline) in comparison with 7 patients (34%) in the mask group (p = 0.02), whose Pao(2)/Fio(2) at treatment discontinuation was higher (p = 0.02) and had fewer complications related to NPPV (ie, skin necrosis, p = 0.01). Moreover, the patients receiving ventilation via helmet required significantly less NPPV discontinuations in the first 24 h of application (p < 0.001) than patients receiving ventilation via face mask. The helmet may represent a valid alternative to a face mask in immunocompromised patients with lung infiltrates and hypoxemic ARF, increasing the patient's tolerance (ie, the number of hours of continuous NPPV use without interruptions) and decreasing the rate of complications directly related to the administration of NPPV.

  17. Reduced Risk of Barrett's Esophagus in Statin Users: Case-Control Study and Meta-Analysis.

    PubMed

    Beales, Ian L P; Dearman, Leanne; Vardi, Inna; Loke, Yoon

    2016-01-01

    Use of statins has been associated with a reduced incidence of esophageal adenocarcinoma in population-based studies. However there are few studies examining statin use and the development of Barrett's esophagus. The purpose of this study was to examine the association between statin use and the presence of Barrett's esophagus in patients having their first gastroscopy. We have performed a case-control study comparing statin use between patients with, and without, an incident diagnosis of non-dysplastic Barrett's esophagus. Male Barrett's cases (134) were compared to 268 male age-matched controls in each of two control groups (erosive gastro-esophageal reflux and dyspepsia without significant upper gastrointestinal disease). Risk factor and drug exposure were established using standardised interviews. Logistic regression was used to compare statin exposure and correct for confounding factors. We performed a meta-analysis pooling our results with three other case-control studies. Regular statin use was associated with a significantly lower incidence of Barrett's esophagus compared to the combined control groups [adjusted OR 0.62 (95 % confidence intervals 0.37-0.93)]. This effect was more marked in combined statin plus aspirin users [adjusted OR 0.43 (95 % CI 0.21-0.89)]. The inverse association between statin or statin plus aspirin use and risk of Barrett's was significantly greater with longer duration of use. Meta-analysis of pooled data (1098 Barrett's, 2085 controls) showed that statin use was significantly associated with a reduced risk of Barrett's esophagus [pooled adjusted OR 0.63 (95 % CI 0.51-0.77)]. Statin use is associated with a reduced incidence of a new diagnosis of Barrett's esophagus.

  18. Dietary food groups intake and cooking methods associations with pancreatic cancer: a case-control study.

    PubMed

    Ghorbani, Zeinab; Hekmatdoost, Azita; Zinab, Hassan Eini; Farrokhzad, Solmaz; Rahimi, Roya; Malekzadeh, Reza; Pourshams, Akram

    2015-05-01

    The role of dietary habits in the etiology of pancreatic cancer (PC) has not yet been well elucidated. The aim of the present study was to examine the association of the frequency of different food groups' intake and their cooking methods with PC risk based on a well-designed case-control study. A case-control study including 307 PC patients and 322 controls referred to four tertiary endosonography centers was conducted from January 2011 to January 2014 to compare the frequency intake of different food items and their cooking methods between cases and controls. After adjustment for gender, age, body mass index, years of education, diabetes and alcohol history, smoking status, and opium use, a significant direct relationship was observed between PC risk and intake frequency (time/week) of bread (OR = 1.50; 95 % CI 1.05-2.13; p-value 0.024), rice (OR = 2.10; 95 % CI 1.15-3.82; p for trend 0.034), and red meat (OR = 2.25; 95 % CI 1.22-4.14; p for trend 0.033) (time/day), when comparing the highest category of intake frequency with the lowest, while increasing frequency of fish consumption was associated with a lower risk of PC (OR = 0.93; 95 % CI0.59-1.47; p for trend 0.009). Increasing consumption of barbecuing red meat and deep fried vegetables was associated with 67 % and 70 % increased risk of PC (p-value 0.025 and 0.006, respectively). Our results indicate that increased frequency of intake of bread, rice, and red meat (especially barbecued) and deep fried vegetables can aggregate PC risk, while increased frequency of fish consumption can protect against PC. However, more studies are still needed.

  19. Diagonal Earlobe Crease as a Significant Marker for Coronary Artery Disease: A Case-control Study.

    PubMed

    Kamal, Rida; Kausar, Komal; Qavi, Ahmed H; Minto, Moeed H; Ilyas, Fariha; Assad, Salman; Shah, Saeed U

    2017-02-05

    To investigate the association between diagonal earlobe crease (DELC) and coronary artery disease (CAD). Limited data exists in South Asia and no prior studies have been performed in Pakistan to assess this relationship. In this case-control study, 200 participants from December 2015 to March 2016 at Shifa International Hospital, Islamabad, Pakistan were enrolled. Consecutive non-probability sampling was used to recruit patients. Cases were enrolled from cardiac care unit (CCU) of the hospital with angiography-proven CAD. Controls were selected from surgical, medical and neurology units of the hospital if they had no previously established evidence or symptoms of CAD. Patients were evaluated in terms of age and any history of hypertension, diabetes and/or smoking. Cases and controls were examined separately by two investigators for the unilateral or bilateral presence of DELC of the lobular portion of either auricle. Patients with ear piercings were excluded from the study. The data was analyzed in statistical product and service solutions (SPSS) (IBM, Delaware, Chicago), and an online statistical software. Out of the 200 patients, 126 (63%) were males and 74 (37%) were females. In the 100 cases, 76 had DELC and 24 had no crease whereas, among the 100 controls, 36 had DELC and 64 had no DELC (p <0.001, OR = 5.63, CI = 2.91-10.93). The prevalence of diseases such as hypertension, diabetes, smoking among the cases and controls were 66%, 53%, 27% and 27%, 18%, 25% respectively. The effect of hypertension and diabetes on the presence of DELC was statistically significant (p <0.05) but the impact of smoking on DELC presence was insignificant (p >0.05). There is a significant association between DELC and CAD. This is the first case-control study from South Asia disclosing this important correlation. Our study also reports a high frequency of DELC in patients suffering from hypertension and diabetes mellitus. No association between smoking and DELC was found.

  20. A case-control study on the effect of hormone replacement therapy on ischaemic heart disease.

    PubMed

    Hippisley-Cox, Julia; Pringle, Mike; Crown, Nicola; Coupland, Carol

    2003-03-01

    Many clinicians believe that hormone replacement therapy (HRT) protects against coronary heart disease (CHD) in women. However, recent reports have cast some doubt on this because of lack of dose-response or duration-response effects. Since CHD is common in women--about half of all postmenopausal women will get it and about a third of these will die from it--the effect of HRT on CHD is of great public health importance. To determine the degree of cardioprotection conferred by HRT, including the effect of duration, time since last issue, the addition of progestogens, route of administration, and dose. Population-based case-control study. Nine general practices recruited from the Trent Focus Collaborative Research Network. A total of 417 female cases with CHD matched by age and practice to 2435 controls with a case-control ratio of 1:5.8 were studied. The main outcome measure was the odds ratio for CHD calculated by conditional logistic regression adjusted for diabetes, hypertension, body mass index, and smoking. No evidence was found, either from univariate analysis or multivariate analysis, that use of HRT was associated with reduced risk of CHD (odds ratio = 1.32; 95% confidence interval = 0.93 to 1.87). Indeed, the trend was in the opposite direction. There was no association for different types of HRT (opposed or unopposed) or routes of administration. Similarly, there was no association for current or past use and no effect for dose or duration. This study adds to growing evidence that HRT does not confer cardioprotection. Until there is robust evidence to the contrary, general physicians need to assess risks and benefits of HRT independently of any possible reduction in risk of CHD.

  1. Sequential analysis of longitudinal data in a prospective nested case-control study.

    PubMed

    Park, Eunsik; Chang, Yuan-chin I

    2010-12-01

    The nested case-control design is a relatively new type of observational study whereby a case-control approach is employed within an established cohort. In this design, we observe cases and controls longitudinally by sampling all cases whenever they occur but controls at certain time points. Controls can be obtained at time points randomly scheduled or prefixed for operational convenience. This design with longitudinal observations is efficient in terms of cost and duration, especially when the disease is rare and the assessment of exposure levels is difficult. In our design, we propose sequential sampling methods and study both (group) sequential testing and estimation methods so that the study can be stopped as soon as the stopping rule is satisfied. To make such a longitudinal sampling more efficient in terms of both numbers of subjects and replications, we propose applying sequential sampling methods to subjects and replications, simultaneously, until the information criterion is fulfilled. This simultaneous sequential sampling on subjects and replicates is more flexible for practitioners designing their sampling schemes, and is different from the classical approaches used in longitudinal studies. We newly define the σ-field to accommodate our proposed sampling scheme, which contains mixtures of independent and correlated observations, and prove the asymptotic optimality of sequential estimation based on the martingale theories. We also prove that the independent increment structure is retained so that the group sequential method is applicable. Finally, we present results by employing sequential estimation and group sequential testing on both simulated data and real data on children's diarrhea. © 2009, The International Biometric Society.

  2. Factors Associated With Unplanned Extubation in Children: A Case-Control Study.

    PubMed

    da Silva, Paulo Sérgio Lucas; Fonseca, Marcelo Cunio Machado

    2017-01-01

    Although several studies assess unplanned extubation (UE) in children, few have addressed determinants of UE and factors associated with reintubation in a case-controlled manner. We aimed to identify the risk factors and outcomes associated with UE in a pediatric intensive care unit. Cases of UE were randomly matched with control patients at a ratio of 1:4 for age, severity of illness, and admission diagnosis. For cases and controls, we also collected data associated with UE events, reintubation, and outcomes. We analyzed 94 UE patients (0.75 UE per 100 intubation days) and found no differences in demographics between the 2 groups. Logistic regression revealed that patient agitation (odds ratio [OR]: 2.44; 95% confidence interval [CI]: 1.28-4.65), continuous sedation infusion (OR: 3.27; 95% CI: 1.70-6.29), night shifts (OR: 9.16; 95% CI: 4.25-19.72), in-charge nurse experience <2 years (OR: 2.38; 95% CI: 1.13-4.99), and oxygenation index (OI) >5 (OR: 76.9; 95% CI: 16.79-352.47) were associated with UE. Risk factors for reintubation after UE included prior level of sedation (COMFORT score < 27; OR: 7.93; 95% CI: 2.30-27.29), copious secretion (OR: 11.88; 95% CI: 2.20-64.05), and OI > 5 (OR: 9.32; 95% CI: 2.45-35.48). This case-control study showed that both patient- and nurse-associated risk factors were related to UE. Risk factors associated with reintubation included lower levels of consciousness, copious secretions, and higher OI. Further evidence-based studies, including a larger sample size, are warranted to identify predisposing factors in UEs.

  3. Limited hip rotation and non-contact anterior cruciate ligament injury: a case-control study.

    PubMed

    Tainaka, Koji; Takizawa, Tsuyoshi; Kobayashi, Hiroyuki; Umimura, Masakazu

    2014-01-01

    Insufficient hip flexibility, a limiting factor for lower extremity rotation, can cause great rotational stress and consequent injury to the knees and ankles. A limited range of motion (ROM) of the hip might be associated with increased risk of non-contact anterior cruciate ligament (ACL) injury. We investigated the association between the risk of non-contact ACL injured student athletes and limitations of hip ROM. A case-control study was conducted at an orthopaedic clinic in Japan. Cases included all patients with non-contact ACL injury and without known marked alignment abnormalities who visited the orthopaedic clinic during 2000-2008. Controls included all patients with non-ACL sports-related injuries who visited the same clinic in 2000. The adjusted odds ratio of ROM of the hip was evaluated for non-contact ACL injury risk. These cases were 44 ACL cases and 123 controls aged 13-17 years. The odds ratios (ORs) of internal and external rotations of hip ROMs were adjusted for age, sex, BMI, type of sports and hip ROM (flexion, extension, adduction, abduction). The adjusted ORs for a 10° increase of the sum of the right and left internal hip rotations were 0.18 (95% confidence interval [CI], 0.10-0.34, p<0.0001), and 0.23 (95% CI, 0.14-0.39, p<0.0001) for external rotations, and the observed ORs were small. Data obtained from this small sample indicate that limited hip rotation ROMs in young athletes have the possibility of association with increased risk of non-contact ACL injury. III - case-control study. © 2013.

  4. Do the poor sue more? A case-control study of malpractice claims and socioeconomic status.

    PubMed

    Burstin, H R; Johnson, W G; Lipsitz, S R; Brennan, T A

    1993-10-13

    To evaluate whether socioeconomic status is associated with risk of malpractice claims, particularly among those who have suffered medical injury. Case-control study. Fifty-one hospitals in New York State. The presence and severity of medical injury, defined as disability at the time of discharge or prolongation of the hospitalization caused by medical treatment as opposed to the disease process, were assessed through review of approximately 31,000 hospital records in New York in 1984. These sampled records were then linked to formal malpractice claims. To estimate the risk of malpractice claims by age, gender, race, insurance status, and income, we conducted a case-control study of claimant cases matched with nonclaimant controls. The cases were all those patients who filed malpractice claims referring to alleged malpractice during a sampled hospitalization. Physician reviewers had previously judged the level of disability that resulted from the medical injury. Claimants (n = 51) were each matched with five nonclaimant controls on the basis of injury. Noninjured cases were matched with noninjured controls and injured cases were matched with injured controls. We found that poor patients (odds ratio [OR], 0.2; 95% confidence interval [CI], 0.03 to 0.8) and uninsured patients (OR, 0.1; 95% CI, 0.005 to 0.9) were significantly less likely to file malpractice claims, after controlling for the severity of medical injury. Among patients who suffered medical injury, the elderly (OR, 0.2; 95% CI, 0.03 to 0.9) were also less likely to file claims. Gender and race were not independently associated with risk of malpractice claims. Poor and uninsured patients are significantly less likely to sue for malpractice, even after controlling for the presence of medical injury. Fear of malpractice risk should not be a significant factor in the decision to serve the poor. Tort reforms that would protect physicians who serve the medically indigent from malpractice suits may not be

  5. Case-control admixture mapping in Latino populations enriches for known asthma-associated genes.

    PubMed

    Torgerson, Dara G; Gignoux, Christopher R; Galanter, Joshua M; Drake, Katherine A; Roth, Lindsey A; Eng, Celeste; Huntsman, Scott; Torres, Raul; Avila, Pedro C; Chapela, Rocio; Ford, Jean G; Rodríguez-Santana, José R; Rodríguez-Cintrón, William; Hernandez, Ryan D; Burchard, Esteban G

    2012-07-01

    Polymorphisms in more than 100 genes have been associated with asthma susceptibility, yet much of the heritability remains to be explained. Asthma disproportionately affects different racial and ethnic groups in the United States, suggesting that admixture mapping is a useful strategy to identify novel asthma-associated loci. We sought to identify novel asthma-associated loci in Latino populations using case-control admixture mapping. We performed genome-wide admixture mapping by comparing levels of local Native American, European, and African ancestry between children with asthma and nonasthmatic control subjects in Puerto Rican and Mexican populations. Within candidate peaks, we performed allelic tests of association, controlling for differences in local ancestry. Between the 2 populations, we identified a total of 62 admixture mapping peaks at a P value of less than 10(-3) that were significantly enriched for previously identified asthma-associated genes (P= .0051). One of the peaks was statistically significant based on 100 permutations in the Mexican sample (6q15); however, it was not significant in Puerto Rican subjects. Another peak was identified at nominal significance in both populations (8q12); however, the association was observed with different ancestries. Case-control admixture mapping is a promising strategy for identifying novel asthma-associated loci in Latino populations and implicates genetic variation at 6q15 and 8q12 regions with asthma susceptibility. This approach might be useful for identifying regions that contribute to both shared and population-specific differences in asthma susceptibility. Copyright © 2012 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

  6. Dental x-rays and the risk of thyroid cancer: a case-control study.

    PubMed

    Memon, Anjum; Godward, Sara; Williams, Dillwyn; Siddique, Iqbal; Al-Saleh, Khalid

    2010-05-01

    The thyroid gland is highly susceptible to radiation carcinogenesis and exposure to high-dose ionising radiation is the only established cause of thyroid cancer. Dental radiography, a common source of low-dose diagnostic radiation exposure in the general population, is often overlooked as a radiation hazard to the gland and may be associated with the risk of thyroid cancer. An increased risk of thyroid cancer has been reported in dentists, dental assistants, and x-ray workers; and exposure to dental x-rays has been associated with an increased risk of meningiomas and salivary tumours. To examine whether exposure to dental x-rays was associated with the risk of thyroid cancer, we conducted a population-based case-control interview study among 313 patients with thyroid cancer and a similar number of individually matched (year of birth +/- three years, gender, nationality, district of residence) control subjects in Kuwait. Conditional logistic regression analysis, adjusted for other upper-body x-rays, showed that exposure to dental x-rays was significantly associated with an increased risk of thyroid cancer (odds ratio = 2.1, 95% confidence interval: 1.4, 3.1) (p=0.001) with a dose-response pattern (p for trend <0.0001). The association did not vary appreciably by age, gender, nationality, level of education, or parity. These findings, based on self-report by cases/controls, provide some support to the hypothesis that exposure to dental x-rays, particularly multiple exposures, may be associated with an increased risk of thyroid cancer; and warrant further study in settings where historical dental x-ray records may be available.

  7. High Seroprevalence of Leptospira Exposure in Meat Workers in Northern Mexico: A Case-Control Study.

    PubMed

    Alvarado-Esquivel, Cosme; Hernandez-Tinoco, Jesus; Sanchez-Anguiano, Luis Francisco; Ramos-Nevarez, Agar; Cerrillo-Soto, Sandra Margarita; Saenz-Soto, Leandro; Martinez-Ramirez, Lucio

    2016-03-01

    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. 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. 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. 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.

  8. Using genetic epidemiology to study Rett syndrome: the design of a case-control study.

    PubMed

    Leonard, H; Fyfe, S; Dye, D; Leonard, S

    2000-01-01

    Rett syndrome is a neurological disorder that is seen almost exclusively in females. Although generally considered to have a genetic basis, the underlying mechanism remains obscure. One favoured hypothesis is that the syndrome is an X-linked dominant disorder, lethal or non-expressed in males. Genealogical research has also suggested that the mode of transmission in Rett syndrome may involve a premutation which over several generations is converted to a full mutation. Geographical clustering has been reported, and it has also been proposed that Rett syndrome is a clinically variable condition and that other neurological disorders may be occurring more commonly in families with Rett syndrome. Other studies have found an apparent increase in intellectual disability and seizures in the extended families of girls with Rett syndrome. The science of genetic epidemiology can be used to identify familial aggregation, which is the clustering of a disorder within a family. We have used a case-control study design to investigate both fetal wastage and familial aggregation of other disorders in families of girls with Rett syndrome. The Australian Rett Syndrome Database provided the source of cases, and control probands were girls of a similar age with normal development. This paper describes the methodology for a case-control study of this rare condition using pedigree data and discusses issues in the collection and evaluation of such data. The use of a control population is an important feature. Both the strengths and the shortcomings of our design are identified, and recommendations are made for future research.

  9. Risk factors of post-traumatic stress disorder (PTSD) after Wenchuan earthquake: a case control study.

    PubMed

    Cheng, Yongzhong; Wang, Fang; Wen, Jin; Shi, Yingkang

    2014-01-01

    Few clues were found in the literature about the independent risk factors for PTSD among earthquake survivors in Sichuan province three years after the 2008 earthquake. Ours was the first case-control study with matching factors of age and distance from the epicenter among survivors age 16 years or older, three years after the catastrophe. To identify independent risk factors for PTSD among earthquake survivors. We performed a population-based matched case-control study. The cases were drawn from earthquake areas three years after the Wenchuan earthquake, including 113 cases who met positive criteria for PTSD symptoms according to the PCL-C (PTSD Checklist-Civilian Version) score and 452 controls who did not meet the criteria. Cases and controls were matched individually by birth year (+ three years) and the town they lived in when the earthquake occurred. Independent risk factors for PTSD symptoms included two-week disease prevalence (odds ratio [OR],1.92; 95% confidence interval [CI],1.18-3.13), witnessing someone being killed in the earthquake (OR, 2.04;95%CI, 1.17-3.58), having no regular income after the earthquake (OR, 0.52; 95%CI, 0.28-0.98), receiving mental health support only one time after the earthquake (OR, 2.43; 95%CI, 1.09-5.42) and lower social support (lower PSSS score) (OR, 0.95; 95%CI, 0.93-0.97). Earthquake experience, suffering from physical illnesses, lack of stable income, and lower social support were associated with PTSD symptoms.

  10. Multilocus genetic risk score associates with ischemic stroke in case-control and prospective cohort studies

    PubMed Central

    Malik, R; Bevan, S; Nalls, MA; Holliday, EG; Devan, WJ; Cheng, YC; Ibrahim-Verbaas, CA; Verhaaren, BF; Bis, JC; Joon, AY; de Stefano, AL; Fornage, M; Psaty, BM; Ikram, MA; Launer, LJ; van Duijn, CM; Sharma, P; Mitchell, BD; Rosand, J; Meschia, JF; Levi, C; Rothwell, PM; Sudlow, C; Markus, HS; Seshadri, S; Dichgans, M

    2014-01-01

    BACKGROUND AND PURPOSE Genome-wide association studies have revealed multiple common variants associated with known risk factors for ischemic stroke (IS). However, their aggregate effect on risk is uncertain. We aimed to generate a multilocus genetic risk score (GRS) for IS based on genome-wide association studies data from clinical-based samples and to establish its external validity in prospective population-based cohorts. METHODS Three thousand five hundred forty-eight clinic-based IS cases and 6399 controls from the Wellcome Trust Case Control Consortium 2 were used for derivation of the GRS. Subjects from the METASTROKE consortium served as a replication sample. The validation sample consisted of 22 751 participants from the Cohorts for Heart and Aging Research in Genomic Epidemiology consortium. We selected variants that had reached genome-wide significance in previous association studies on established risk factors for IS. RESULTS A combined GRS for atrial fibrillation, coronary artery disease, hypertension, and systolic blood pressure significantly associated with IS both in the case-control samples and in the prospective population-based studies. Subjects in the top quintile of the combined GRS had >2-fold increased risk of IS compared with subjects in the lowest quintile. Addition of the combined GRS to a simple model based on sex significantly improved the prediction of IS in the combined clinic-based samples but not in the population-based studies, and there was no significant improvement in net reclassification. CONCLUSIONS A multilocus GRS based on common variants for established cardiovascular risk factors was significantly associated with IS both in clinic-based samples and in the general population. However, the improvement in clinical risk prediction was found to be small. PMID:24436234

  11. Heel ulcers - Pressure ulcers or symptoms of peripheral arterial disease? An exploratory matched case control study.

    PubMed

    Twilley, Heidi; Jones, Sarahjane

    2016-05-01

    To investigate the relationship between pressure ulcers of the heel and peripheral arterial disease (PAD) and determine the feasibility of conducting a statistically powered matched case control study. Evidence indicates a relationship between chronic leg ulcers and vascular disease. The relationship between pressure ulcers of the heel and vascular disease is less well established. A matched case control study. Data were collected between March 2014 and January 2015. 15 patients identified as having a grade 2, 3 or 4 pressure ulcer of the heel were compared with 15 matched controls without pressure ulcers of the heel. The primary clinical outcome measure was the ankle brachial pressure index (ABPI), where an ABPI <0.9 or >1.3 was considered clinically indicative of PAD. The primary feasibility outcome measure was the rate of recruitment. Eighty seven patients were reported as having foot and heel ulcers; 36 of whom were identified as having pressure ulcers of the heel, 15 (42%) of whom were recruited to the study. Patients presenting with pressure ulcers of the heel were significantly more likely to simultaneously have previously undiagnosed PAD compared with age, gender and ethnicity matched controls without pressure ulcers of the heel (odds ratio: 11, 95% confidence interval 1.99-60.57). The formation of pressure ulcers of the heel could, in some patients, be related to the presence of PAD rather than a consequence of poor quality care. Healthcare professionals should assess the patient to exclude or confirm PAD. Copyright © 2016 Tissue Viability Society. Published by Elsevier Ltd. All rights reserved.

  12. Health issues in the Arab American community. Male infertility in Lebanon: a case-controlled study.

    PubMed

    Kobeissi, Loulou; Inhorn, Marcia C

    2007-01-01

    The impact of risk factors, such as consanguinity and familial clustering, reproductive infections, traumas, and diseases, lifestyle factors and occupational and war exposures on male infertility, was investigated in a case-controlled study conducted in Lebanon. One-hundred-twenty males and 100 controls of Lebanese, Syrian or Lebanese-Palestinian descents were selected from two in-vitro fertilization (IVF) clinics located in Beirut, Lebanon. All cases suffered from impaired sperm count and function, according to World Health Organization guidelines for semen analysis. Controls were the fertile husbands of infertile women. Data were collected using a semi-structured interview, laboratory blood testing and the results of the most recent semen analysis. Univariate, bivariate and multivariate logistic regression analyses were used for data analysis, along with checks for effect modification and control of confounders. Consanguinity and the familial clustering of male infertility cases, as well as reproductive illnesses and war exposures were independently significant risk factors for male infertility. The odds of having infertility problems in the immediate family were 2.6 times higher in cases than controls. The odds of reproductive illness were 2 times higher in cases than controls. The odds of war exposures were 1.57 times higher in cases than controls. Occupational exposures, such as smoking and caffeine intake, were not shown to be important risk factors. This case-controlled study highlights the importance of investigating the etiology of male infertility in Middle Eastern communities. It suggests the need to expand research on male reproductive health in the Middle East in order to improve the prevention and management of male infertility and other male reproductive health problems.

  13. Maternal and neonatal risk factors for childhood type 1 diabetes: a matched case-control study.

    PubMed

    Robertson, Lynn; Harrild, Kirsten

    2010-05-27

    An interaction between genetic susceptibility and environmental factors is thought to be involved in the aetiology of type 1 diabetes. The aim of this study was to investigate maternal and neonatal risk factors for type 1 diabetes in children under 15 years old in Grampian, Scotland. A matched case-control study was conducted by record linkage. Cases (n = 361) were children born in Aberdeen Maternity Hospital from 1972 to 2002, inclusive, who developed type 1 diabetes, identified from the Scottish Study Group for the Care of Diabetes in the Young Register. Controls (n = 1083) were randomly selected from the Aberdeen Maternity Neonatal Databank, matched by year of birth. Exposure data were obtained from the Aberdeen Maternity Neonatal Databank. Conditional logistic regression was used to evaluate the association between various maternal and neonatal factors and the risk of type 1 diabetes. There was no evidence of statistically significant associations between type 1 diabetes and maternal age, maternal body mass index, previous abortions, pre-eclampsia, amniocentesis, maternal deprivation, use of syntocinon, mode of delivery, antepartum haemorrhage, baby's sex, gestational age at birth, birth order, birth weight, jaundice, phototherapy, breast feeding, admission to neonatal unit and Apgar score (P > 0.05). A significantly decreased risk of type 1 diabetes was observed in children whose mothers smoked at the booking appointment compared to those whose mothers did not, with an adjusted OR of 0.67, 95% CI (0.46, 0.99). This case-control study found limited evidence of a reduced risk of the development of type 1 diabetes in children whose mothers smoked, compared to children whose mothers did not. No evidence was found of a significant association between other maternal and neonatal factors and childhood type 1 diabetes.

  14. XM: Association Testing on the X-Chromosome in Case-Control Samples with Related Individuals

    PubMed Central

    Thornton, Timothy; Zhang, Qian; Cai, Xiaochen; Ober, Carole; McPeek, Mary Sara

    2013-01-01

    Genetic variants on the X-chromosome could potentially play an important role in some complex traits. However, development of methods for detecting association with X-linked markers has lagged behind that for autosomal markers. We propose methods for case-control association testing with X-chromosome markers in samples with related individuals. Our method, XM, appropriately adjusts for both correlation among relatives and male-female allele copy number differences. Features of XM include: (1) it is applicable to and computationally feasible for completely general combinations of family and case-control designs; (2) it allows for both unaffected controls and controls of unknown phenotype to be included in the same analysis; (3) it can incorporate phenotype information on relatives with missing genotype data; and (4) it adjusts for sex-specific trait prevalence values. We propose two other tests, Xχ and XW, which can also be useful in certain contexts. We derive the best linear unbiased estimator of allele frequency, and its variance, for X-linked markers. In simulation studies with related individuals, we demonstrate the power and validity of the proposed methods. We apply the methods to X-chromosome association analysis of (1) asthma in a Hutterite sample and (2) alcohol dependence in the GAW 14 COGA data. In analysis (1), we demonstrate computational feasibility of XM and the applicability of our robust variance estimator. In analysis (2), we detect significant association, after Bonferroni correction, between alcohol dependence and SNP rs979606 in the MAOA gene, where this gene has previously been found to be associated with substance abuse and antisocial behavior. PMID:22552845

  15. 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

  16. Association between protozoa in sputum and asthma: a case-control study.

    PubMed

    van Woerden, Hugo C; Ratier-Cruz, Adriana; Aleshinloye, Olabode B; Martinez-Giron, Rafael; Gregory, Clive; Matthews, Ian P

    2011-06-01

    Atypical infectious agents have been proposed as potential contributors to asthma. A novel set of morphological and staining criteria permit the identification of flagellated protozoa in sputum. This case-control study was designed to use this novel method and to assess: (1) are protozoa more common in asthmatics than in non-asthmatics; (2) is the presence of protozoa associated with the use of steroid inhalers; and (3) is the presence of protozoa associated with living in damp housing? Induced sputum samples were collected from asthma patients and local non-atopic, non-smoking controls. Questionnaires assessed asthma severity and housing conditions. Sputum was examined for flagellated protozoa using a previously described staining technique. 96 participants were recruited for this study; 54 asthma patients and 42 controls, age range 21-62 years, 70% female participants. Limiting results to those who were clearly positive or negative for flagellated protozoa, 66.7% (20/30) of asthmatics and 30.8% (4/13) of controls had protozoa (p = 0.046). Among the asthma patients, prevalence of protozoa was not significantly different between those who had (10/18), and those who had not (10/12), used steroid inhaler in the preceding two weeks (p = 0.11). Similarly, the prevalence of protozoa was not significantly different between those who did (6/11) and those who did not (18/32), live in damp homes (p = 0.92). This case-control study demonstrates an association between flagellated protozoa in sputum and asthma. It is now necessary to confirm and characterise the protozoa using genetic techniques based on 18S ribosomal RNA. Once tis is established it would be worthwhile to determine if asthma symptoms improve when treated by anti-protozoal agents. Copyright © 2010 Elsevier Ltd. All rights reserved.

  17. 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

  18. Metformin intake is associated with better survival in ovarian cancer: a case-control study.

    PubMed

    Kumar, Sanjeev; Meuter, Alexandra; Thapa, Prabin; Langstraat, Carrie; Giri, Shailendra; Chien, Jeremy; Rattan, Ramandeep; Cliby, William; Shridhar, Viji

    2013-02-01

    The objective of this case-control study was to identify any association of metformin intake with the survival of patients with ovarian cancer. In this retrospective case-control study, women with ovarian cancer who received metformin (cases) were compared with women with ovarian cancer who did not receive metformin (controls). A 2-layered analysis was conducted. In preliminary analysis, all cases (the OC cohort) were compared with controls at a 1:2 ratio. Subsequently, in definitive analysis, only patients who had epithelial ovarian cancer (the EOC cohort) were compared with controls at a 1:3 ratio. In the EOC cohort, cases were matched with controls for age (±5 years), International Federation of Gynecology and Obstetrics stage, and residual disease. Prognostic variables and disease specific survival were compared using chi-square tests, the Kaplan-Meier (log-rank) method, and Cox proportional hazards analysis. In a preliminary analysis of the OC cohort (72 cases and 143 controls), cases had better survival (5-year disease-specific survival for cases vs controls, 73% vs 44%; P = .0002). In the definitive analysis of the EOC cohort (61 cases and 178 controls), the distribution of age, disease stage, optimal cytoreduction, serous histology, and platinum chemotherapy remained similar between cases and controls (P > .05). Despite these similarities, cases had significantly better survival (5-year disease-specific survival for cases vs controls, 67% vs 47%; P = .007). On multivariate analysis, metformin remained an independent predictor of survival (hazard ratio, 2.2; 95% confidence interval, 1.2-3.8; P = .007) after controlling for disease stage, grade, histology, chemotherapy, body mass index, and surgical cytoreduction. The results of this study indicated an association of metformin intake with survival in patients with ovarian cancer. The receipt of metformin was associated with better survival, and the authors concluded that metformin is worthy of clinical

  19. Case-control association study of TGOLN2 in attempted suicide.

    PubMed

    Mahon, Pamela B; Stütz, Adrian M; Seifuddin, Fayaz; Huo, Yuqing; Goes, Fernando S; Jancic, Dubravka; Judy, Jennifer T; Depaulo, J Raymond; Gershon, Elliot S; McMahon, Francis J; Zandi, Peter P; Potash, James B; Willour, Virginia L

    2010-07-01

    Family, twin, and adoption studies provide convincing evidence for a genetic contribution to suicidal behavior. The heritability for suicidal behavior depends in part on the transmission of psychiatric disorders, such as mood disorders and substance use disorders, but is also partly independent of them. Three linkage studies using the attempted suicide phenotype in pedigrees with bipolar disorder, major depression, or alcoholism have provided consistent evidence that 2p11-12 harbors a susceptibility gene for attempted suicide. A microarray expression study using postmortem brain samples has implicated a gene from the 2p11-12 candidate region, the trans-Golgi network protein 2 (TGOLN2) gene, as being consistently up-regulated in suicide cases as compared to controls. Here, we present a TGOLN2 case-control association study using nine single nucleotide polymorphisms (SNPs). These nine SNPs, which include seven tag SNPs and two coding SNPs, have been genotyped in 517 mood disorder subjects with a history of attempted suicide and 515 normal controls. Allelic and genotypic analyses of the case-control sample did not provide evidence for association with the attempted suicide phenotype. Eight of the nine SNPs provided supportive evidence for association (P-values ranging from 0.008 to 0.03) when we compared the attempted suicide cases with a history of alcoholism to the attempted suicide cases without a history of alcoholism. However, this association finding was not replicated in an independent sample. Taken together, these analyses do not provide support for the hypothesis that common genetic variation in TGOLN2 contributes significantly to the risk for attempted suicide in subjects with major mood disorders.

  20. 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

  1. Risk factors for cellulitis in patients with lymphedema: a case-controlled study.

    PubMed

    Teerachaisakul, M; Ekataksin, W; Durongwatana, S; Taneepanichskul, S

    2013-09-01

    Risk factors for cellulitis in lymphedema (LE) have never been evaluated in controlled studies. The objective of this study was to assess the risk factors for cellulitis in patients with LE using a case-controlled study method. Medical records of patients from November 2009 to September 2011 who met the following criteria were retrieved and analyzed: (a) clinical diagnosis of LE of the limb, (b) aged 18 or above, (c) no food allergy history and (d) no medical diagnosis of cancer metastasis. Overall, there were 179 cases of LE with cellulitis. Each case was matched by age (+/- 5 years) and gender with a patient with LE and without cellulitis for controls. Logistic regression with backward selection procedure was used to identify independent risk factors. The area under the receiver operating characteristics (ROC) curve of the final model was calculated. Independent risk factors for cellulitis in patients with LE were percentage difference in circumference of the limb (adjusted odds ratio (AOR)=1.07, 95% confidence interval (CI)=1.04-1.10), primary LE diagnosis (AOR=3.36, 95% CI=1.37-8.22), food-induced complication experiences (FIE: AOR=6.82, 95% CI=2.82-16.51) and systolic blood pressure (AOR=1.02, 95% CI=1.01-1.04). The area under the curve for the model was 0.80 (95% CI=0.75-0.85, p<0.001). No association was observed with hypertension, diabetes mellitus, body mass index and the duration of LE. This first case-controlled study highlights the important roles of dietary factors, percentage difference in circumference of the limb, and systolic blood pressure for developing cellulitis. The results suggest that controlling the percentage difference in circumference of the limb and systolic blood pressure together with restriction of fatty food and meat consumption may result in a decreased incidence of cellulitis among patients with LE.