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Conditional Logistic Regression Analysis (conditional + logistic_regression_analysis)
Selected AbstractsOccupation and breast cancer risk in Polish women: A population-based case-control studyAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 2 2007Beata Peplonska MD Abstract Background The etiology of breast cancer is not well understood and the role of occupational exposures in breast carcinogenesis is still uncertain. Methods The population-based case-control study included 2,386 incident breast cancer cases diagnosed in 2000,2003, and 2,502 controls. Lifetime occupational histories and information on other potential breast cancer risk factors were obtained through personal interviews. Conditional logistic regression analyses calculated odds ratios (ORs) associated with various occupations and industries after control for potential confounders. Results We found statistically significant excesses of breast cancer among engineers (OR=2.0; 95% CI: 1.0,3.8), economists (2.1; 1.1,3.8), sales occupations-retail (1.2; 1.0,1.5), and other sales occupations (1.2; 1.0,1.5). Industries showing significantly elevated risks included special trade contractors (2.2; 1.2,4.3), electronic and electric equipment manufacturers (1.7; 1.1,2.7); and public administration/general government n.e.c. (2.7; 1.3,5.7). Each of these findings was supported by a statistically significant positive trend for duration of employment (P<0.05). A decreased breast cancer risk was observed in janitors and cleaners (0.7; 0.5,0.8). Conclusions In this study, we found few associations for breast cancer and occupations or industries. The suggestive findings for the electronic and electric equipment manufacturing industry and for the occupations with potential exposure to magnetic fields deserve further evaluation. Am. J. Ind. Med. 50:97,111, 2007. © 2006 Wiley-Liss, Inc. [source] Non-hospital delivery and permanent congenital and early-onset hearing loss in a developing countryBJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 11 2008BO Olusanya Objective, The objective of this study was to determine the role of non-hospital delivery and other risk factors for permanent congenital and early-onset hearing loss (PCEHL) in a developing country. Design, Matched case,control study. Setting, Four primary healthcare centres in inner-city Lagos, Nigeria. Population, Fifty-six infants with PCEHL and 280 normal hearing controls matched for age and sex from a population of infants not older than 3 months attending Bacille de Calmette-Guérin immunisation clinics. Methods, Conditional logistic regression analyses of infant and maternal characteristics associated with PCEHL, and the evaluation of population exposure to each risk factor. Main outcome measures, Adjusted matched odds ratios and population attributable risk percent (PAR%). Results, Children with PCEHL were significantly more likely to be first born (OR 1.9, 95% CI 1.1,3.6) without skilled attendants at birth (OR 2.4, 95% CI 1.3,4.5) and have a history of neonatal jaundice requiring exchange blood transfusion (NNJ/EBT) (OR 9.6, 95% CI 2.4,38.2) but less likely to be small for gestational age (SGA) (OR 0.1, 95% CI 0.0,0.5). After controlling for other covariates, the absence of skilled attendants at birth (OR 4.2, 95% CI 2.0,8.6) and NNJ/EBT (OR 19.1, 95% CI 4.3,85.5) emerged as predictors of PCEHL, while SGA (OR 0.1, 95% CI 0.0,0.2) retained its inverse relationship with PCEHL. The PAR% was 35.9% for the lack of skilled attendants at birth and 10.6% for having NNJ/EBT. About 23% of children with PCEHL did not exhibit any risk factors. Conclusions, NNJ/EBT and the absence of skilled attendant at birth rather than the place of delivery are significant predictors of PCEHL in this study population. Targeted hearing screening using these risk factors would facilitate the detection of about 77% of children with PCEHL. [source] Whip use and race progress are associated with horse falls in hurdle and steeplechase racing in the UKEQUINE VETERINARY JOURNAL, Issue 5 2004G. L. PINCHBECK Summary Reasons for performing study: Falls during racing present a risk of injury to both horse and jockey and a risk of fatality to horses. Objectives: To use video recordings of races to describe the circumstances surrounding horse falls at hurdle and steeplechase fences and to identify and quantify within-race risk factors for horse falls in National Hunt racing in the UK. Methods: A retrospective, matched, nested case-control study using video recordings of races was conducted on 6 UK racecourses. Cases and controls were matched on both race type and jump number at which the fall occurred. Conditional logistic regression analysis was used to examine the univariable and multivariable relationship between predictor variables and the risk of falling. Results: The risk of falling was significantly associated with whip use and race progress. Horses which were being whipped and progressing through the race were at greater than 7 times the risk of falling compared to horses which were not being whipped and which had no change in position or lost position through the field. Conclusions: This study has identified whip use and the position of the horse with respect to others in the field as potential risk factors for horse falls. Potential relevance: If these findings are confirmed by the use of intervention trials (e.g. with whip-free or restricted whip use races), modifications could be introduced which would reduce the frequency of horse falls, leading to improved equine welfare. [source] Hemorrhagic stroke associated with antidepressant use in patients with depression: does degree of serotonin reuptake inhibition matter?PHARMACOEPIDEMIOLOGY AND DRUG SAFETY, Issue 3 2009Yan Chen MD Abstract Objective This study aimed to determine whether the degree of serotonin (5-HT) reuptake inhibition affects risk of hemorrhagic stroke associated with antidepressant use in patients with depression. Method A population-based, nested case-control study was performed using a managed care medical claims database. Ninety two depressed patients with a diagnosis of hemorrhagic stroke were identified and matched with 552 controls by age, sex, and year of index date of depression (IDD). Diagnoses of depression, hemorrhagic stroke, and other medical comorbidities were identified using ICD-9 codes. Antidepressants were classified as high, medium, or low reuptake inhibition based on their affinities for the 5-HT reuptake transporter, determined using their respective equilibrium dissociation constants (KD; high: KD,<,1,nM; medium: 1,,,KD,<,10,nM; low: KD,,,10,nM). Conditional logistic regression analysis was performed to estimate the crude and adjusted odds ratios (ORs) with 95% confidence intervals (CIs) of the risk of hemorrhagic stroke. Results Compared to non-users of antidepressants, risk of hemorrhagic stroke did not significantly differ between patients who had ever used antidepressants with high (OR,=,0.82; 95% CI,=,0.44,1.55), medium (OR,=,0.93; 95% CI,=,0.37,2.31), or low (OR,=,0.38; 95% CI,=,0.11,1.41) 5-HTT inhibition. Conclusion Risk of hemorrhagic stroke associated with antidepressant use may not be related to an antidepressant's degree of 5-HT reuptake inhibition. Given the limitations of this study, additional studies are needed to confirm these findings. Copyright © 2009 John Wiley & Sons, Ltd. [source] The relationship between computerized physician order entry and pediatric adverse drug events: a nested matched case-control study,PHARMACOEPIDEMIOLOGY AND DRUG SAFETY, Issue 8 2009Feliciano Yu MD, MSPH Abstract This study assesses the impact of computerized physician order entry (CPOE) implementation in pediatric hospitals on reported adverse drug events. Using a nested matched case-control design; we linked CPOE implementation information from the health information management systems society analytics database with reported adverse drug event (ADE) from the national association of children's hospitals and related institutions case mix comparative data program. Differences were examined using univariate and multivariate conditional logistic regression analyses. Patients from CPOE hospitals were more frequently seen in larger hospitals have more co-morbidities than those from non-CPOE hospitals. When matched by admitting diagnosis, age, gender and race, ADE cases were associated with more reported co-morbidities, and were reported less frequently in hospitals with CPOE. Patients from hospitals without CPOE were 42% more likely to experience reportable ADE after adjusting for the presence of co-morbidities. In conclusion, we found significant beneficial associations between reportable ADE and CPOE adoption in a representative sample of pediatric hospitals. Copyright © 2009 John Wiley & Sons, Ltd. [source] Identification of occupational cancer risk in British Columbia: A population-based case,control study of 2,998 lung cancers by histopathological subtypeAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 3 2009Amy C. MacArthur MHSc Abstract Background Few studies have investigated occupational lung cancer risk in relation to specific histopathological subtypes. Methods A case,control study was conducted to evaluate the relationship between lung cancer and occupation/industry of employment by histopathological subtype. A total of 2,998 male cases and 10,223 cancer controls, diagnosed between 1983 and 1990, were identified through the British Columbia Cancer Registry. Matched on age and year of diagnosis, conditional logistic regression analyses were performed for two different estimates of exposure with adjustment for potentially important confounding variables, including tobacco smoking, alcohol consumption, marital status, educational attainment, and questionnaire respondent. Results For all lung cancers, an excess risk was observed for workers in the primary metal (OR,=,1.31, 95% CI, 1.01,1.71), mining (OR,=,1.53, 95% CI, 1.20,1.96), machining (OR,=,1.33, 95% CI, 1.09,1.63), transport (OR,=,1.50, 95% CI, 1.08,2.07), utility (OR,=,1.60, 95% CI, 1.22,2.09), and protective services (OR,=,1.27, 95% CI, 1.05,1.55) industries. Associations with histopathological subtypes included an increased risk of squamous cell carcinoma in construction trades (OR,=,1.25, 95% CI, 1.06,1.48), adenocarcinoma for professional workers in medicine and health (OR,=,1.73, 95% CI, 1.18,2.53), small cell carcinoma in railway (OR,=,1.62, 95% CI, 1.06,2.49), and truck transport industries (OR,=,1.51, 95% CI, 1.00,2.28), and large cell carcinoma for employment in the primary metal industry (OR,=,2.35, 95% CI, 1.11,4.96). Conclusions Our results point to excess lung cancer risk for occupations involving exposure to metals, polyaromatic hydrocarbons and asbestos, as well as several new histopathologic-specific associations that merit further investigation. Am. J. Ind. Med. 52:221,232, 2009. © 2008 Wiley-Liss, Inc. [source] Birth characteristics and hepatoblastoma risk in young childrenCANCER, Issue 5 2004Peggy Reynolds Ph.D. Abstract BACKGROUND Although hepatoblastoma is a very rare childhood cancer, its incidence appears to be rising, especially among children with very low birth weight. With the exception of documented correlations with certain congenital anomalies, the etiology of hepatoblastoma remains largely unknown. METHODS Using California's population-based cancer registry, the authors identified 113 children ages birth,4 years with hepatoblastoma who were diagnosed between 1988 and 1997. Ninety-nine of those 113 children (88%) were matched to a California birth certificate, and randomly selected controls from the same birth certificate files were matched to cases (4:1) according to the month and year of birth and gender. Odds ratios (OR) and 95% confidence intervals (95% CI) were estimated using conditional logistic regression analyses. RESULTS A strikingly elevated risk of hepatoblastoma was found in children who were born with very low birth weight (< 1500 g; OR, 50.57; 95% CI, 6.59,387.97). A plot of the distribution by birth weight showed interesting peaks at birth weights < 1000 g and 3000,3499 g among cases. Children who weighed < 1000 g showed a statistically significant, linear trend toward being diagnosed at an older age (P = 0.036), which seemed to be explained in part by gestational age. CONCLUSIONS The results confirmed previously reported findings of an increased hepatoblastoma risk among children with very low birth weight and suggested that the etiology may differ between children with very low birth weight and children with normal birth weight. Cancer 2004;100:1070,6. © 2004 American Cancer Society. [source] Matched case,control study to evaluate risk factors for hyperlactataemia in HIV patients on antiretroviral therapyHIV MEDICINE, Issue 4 2003D Datta Background Lactic acidosis is a life-threatening event during antiretroviral therapy (ART). Hyperlactataemia may be a prelude to acidosis. Our database study suggested that female gender, intercurrent illness and didanosine (ddI)-based regimens may increase risk of lactic acidosis. The aim of this matched case,control study was to identify risk factors for hyperlactataemia requiring screening. Methods Cases were defined as patients with two consecutive lactate samples ,3.5 mmol/L taken more than 1 week apart. Cases were matched to two controls on gender, use of ddI and total duration of therapy using a 6-month window on either side. Controls never had raised lactate >2.5 mmol/L. A conditional logistic regression analysis using the PHREG procedure in SAS (SAS Institute Inc, Cary, NC) was performed with a discreet logistic model stratified by matching variables. Results Twenty-one cases were matched to 42 controls. In the univariate model, current use of stavudine (d4T), total cholesterol >5.3 mmol/L and glucose levels ,5.2 mmol/L gave increased likelihood of persistent hyperlactataemia. The multivariate model showed current use of d4T to be a significant independent predictor of persistent hyperlactataemia. Conclusions The results of this case,control study indicate that, when controlling for ddI use, d4T use is an additional risk factor for hyperlactataemia. [source] A case-control study on hormone therapy as a risk factor for breast cancer in Finland: Intrauterine system carries a risk as wellINTERNATIONAL JOURNAL OF CANCER, Issue 2 2010Heli K. Lyytinen Abstract The purpose of this study was to evaluate the association between postmenopausal hormone therapy (HT) and the risk for breast cancer in recently postmenopausal Finnish women. All Finnish women with first invasive breast cancer diagnosed between the ages of 50 and 62 years during 1995,2007 (n = 9,956) were identified from the Finnish Cancer Registry. For each case, 3 controls of the same age were retrieved from the Finnish Population Register. The cases and controls were linked to the national medical reimbursement register to assess the use of HT. The odds ratios (ORs) and 95% confidence intervals (CIs) for breast cancer were calculated with conditional logistic regression analysis, adjusting for parity, age at the first birth and health care district. Estradiol-only therapy (991 users with breast cancer, n) or oral progestagen (n = 138) was not accompanied by an increased risk. Estradiol-progestagen therapy (EPT) (n = 1,731) was associated with an elevated risk in the whole series (OR 1.36; 95% CI 1.27,1.46). The risk became detectable in less than 3 years of use. Continuous EPT use tended to be associated with a higher risk for breast cancer than the sequential EPT use. The use of tibolone (n = 80) (1.36; 1.15,1.96), a levonorgestrel-releasing intrauterine system (LNG,IUS) alone (n = 154) (1.45; 1.97,1.77) or as a complement to estradiol (n = 137) (2.15; 1.72,2.68) was also associated with an increased risk. The association between HT use and the risk for breast cancer shows a large variation between various forms of HT, and also the use of LNG-IUS may carry a risk. [source] Association of chili pepper consumption, low socioeconomic status and longstanding gallstones with gallbladder cancer in a Chilean populationINTERNATIONAL JOURNAL OF CANCER, Issue 4 2002Iván Serra Abstract We explored the risk factors for gallbladder cancer and explanations for its sharp and constant incidence increase in Chile since the 1970s. We compared 114 consecutive patients with verified gallbladder cancer, diagnosed 1992,1995, to 114 matched hospital patients with gallstones, using conditional logistic regression analysis. Low education showed a nonsignificant positive relationship with gallbladder cancer [odds ratio (OR) = 2.3, 95% confidence interval (CI) 0.8,6.2], and low socioeconomic level showed a significant relationship (OR = 5.0, 95% CI 1.5,17.3). A very long history of gallstone disease was significantly more prevalent among cases (OR = 11.0, 95% CI 1.4,85.2). Significant red chili pepper consumption was observed in gallbladder cancer patients (OR = 2.9, 95% CI 1.6,5.2). Low intake of both fresh fruit and sugar as soft drinks was associated with gallbladder cancer, with ORs of 6.4 (95% CI 1.4,30.3) and 3.6 (95% CI 1.3,10.1), respectively. Multivariate analysis kept only a very low socioeconomic status and red chili pepper consumption as significant independent risk factors for gallbladder cancer, ORs of 6.3 (95% CI 1.7,23.0) and 3.2 (95% CI 1.7,5.9). Longstanding gallstone cases were removed from the multivariate model because all were in the low and very low socioeconomic groups, reinforcing the association. Patients with gallbladder cancer differed from matched controls by exhibiting lower socioeconomic levels, having a much longer history of gallstone disease and presenting a dietary pattern characterized by high red chili pepper consumption and low fresh fruit intake. © 2002 Wiley-Liss, Inc. [source] Association of penile lichen sclerosus and oncogenic human papillomavirus infectionINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 6 2006Maria Rita Nasca MD Background, Data on the prevalence of human papillomavirus (HPV) infection in patients with penile lichen sclerosus (LS) are scant and controversial. Aim, To investigate the prevalence of HPV infections in patients with penile LS. Methods, HPV infection was assessed by polymerase chain reaction (PCR) in paraffin-embedded penile biopsies obtained from the glans or inner foreskin of 46 adult patients with penile LS, and in brush cytology smears of penile healthy mucosa from an equal number of randomly selected control males matched for age. Statistical evaluation was performed using conditional logistic regression analysis. Results, PCR disclosed the presence of HPV infection in 17.4% of LS patients (HPV 16, six cases; HPV 18, one case; HPV 45, one case). Amongst the controls, HPV infection occurred in 8.7% of patients (HPV 16, two cases; HPV 53, one case; HPV 70, one case). Statistical regression analysis confirmed that the rate of HPV infection was higher amongst patients with genital LS than amongst healthy controls [odds ratio (OR), 2.55; 95% confidence interval (CI), 0.73,8.89]. Conclusions, Infection with oncogenic "high-risk" HPV types in patients with genital LS may enhance the risk of penile cancer arising on LS. [source] Interactions between Helicobacter pylori and other risk factors for peptic ulcer bleedingALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 3 2002W. A. Stack To investigate the role of Helicobacter pylori, expressing the virulence marker CAGA (cytotoxin associated gene product A) in ulcer complications and its interaction with nonsteroidal anti-inflammatory drugs (NSAIDs) and other risk factors. Design: Case control study using conditional logistic regression analysis. Setting: University and City Hospitals, Nottingham. Subjects: 203 consecutive patients with ulcer bleeding and 203 age- and sex-matched controls. Results: Ulcer bleeding was more likely with positive H. pylori serology (odds ratio = 3.3, 95% CI: 1.7,6.6 for CagA positive, but only OR = 1.6, 95% CI: 0.7,3.7 for CagA negative serology), current smoking (OR 2.2, 95% CI: 1.04,4.7), aspirin , 300 mg daily (OR 7.7, 95% CI: 2.8,20.6), all other nonsteroidal anti-inflammatory drugs (NSAIDs: OR 10.6, 95% CI: 3.1,35.7 for , 1 defined daily dose lower and OR 22.6, 95% CI: 6.2,82.0 for higher doses) and past ulcer history (OR 5.6, 95% CI: 2.3,14.1). Aspirin , 300 mg daily was used by 25.1% of patients vs. 7.4% of controls. Smoking only enhanced risk in the presence of H. pylori, with a synergistic interaction (interaction odds ratio = 4.9, 2.4,9.9, P=0.002). Conversely, risks with non-aspirin NSAIDs were reduced in the presence of H. pylori, particularly if CagA-positive (interaction odds ratio=0.21, 0.05,0.9, P=0.03). Conclusions: CagA positive H. pylori infection is associated with an increased risk of ulcer bleeding. The risk from non-aspirin NSAIDs is even higher, but is less in H. pylori infected people. Low-dose aspirin is now commonly associated with ulcer bleeding. [source] | ||||||||||