Multicenter case-control study of the risk factors for ulcerative colitis in China

AIM:To evaluate potential risk factors in the development of ulcerative colitis(UC) in China.METHODS:A total of 1308 patients with UC and 1308 age-matched and sex-matched controls were prospectively studied in China.The UC cases were collected from 17 hospitals in China from April 2007 to April 2010.Uniform questionnaires were designed to investigate risk factors including smoking,appendectomy,stress,socio-economic conditions,nonsteroidal antiinflammatory drugs(NSAIDs),oral contraceptives,diet,breastfeeding,infections and family sanitary conditions.Group comparisons by each factor were done using simple logistic regression analysis.Conditional logistic regression was used for multivariate analysis.RESULTS:By univariate analysis,the variables predictive of UC included feeling stress,light and heavy alcoholic drinking,spicy food,sugar consumption and infectious diarrhea,while heavy tea intake and tap water consumption were protective against UC.On multivariate analysis,the protective factor for UC was tap water consumption [odds ratios(OR) = 0.424,95%CI:0.302-0.594,P < 0.001];while the potential risk factors for UC were heavy sugar consumption(OR = 1.632,95%CI:1.156-2.305,P < 0.001),spicy food(light intake:OR = 3.329,95%CI:2.282-4.857,P < 0.001;heavy intake:OR = 3.979,95%CI:2.700-5.863,P < 0.001),and often feeling stress(OR = 1.981,95%CI:1.447-2.711,P < 0.001).Other factors,such as smoking habit,appendectomy,breastfeeding,a history of measles,rural or urban residence,education,oral contraceptives,and NSAID use have not been found to have a significant association with the development of UC in the present study.CONCLUSION:Our study showed tap water consumption was a protective factor for UC,while spicy food,heavy sugar consumption and often feeling stress were risk factors for UC in this Chinese population.

Risk factors for liver-related mortality in chronic hepatitis C patients:A deceased case-living control study

AIM: To investigate the risk factors for liver-related mortality in chronic hepatitis C (CHC) patients.

Risk factors of intrahepatic cholangiocarcinoma in patients with hepatolithiasis:a case-control study

BACKGROUND:Why 3.3% to 10% of all patients with hepatolithiasis develop intrahepatic cholangiocarcinoma (ICC) remains unknown.We carried out a hospital-based case-control study to identify risk factors for the development of ICC in patients with hepatolithiasis in China.METHODS:Eighty-seven patients with pathologically diagnosed hepatolithiasis associated with ICC and 228 with hepatolithiasis alone matched by sex,age (±2 years),hospital admittance and place of residence were interviewed during the period of 2000-2008.Odds ratios (OR) and 95% confidence intervals (CI) were calculated for each risk factor.RESULTS:Among the patients with hepatolithiasis associated with ICC,the mean age was 57.7 years and 61.0% were female Univariate analysis showed that the significant risk factors for ICC development in hepatolithiasis were smoking,family history of cancer,appendectomy during childhood (under age 20),and duration of symptoms >10 years.In multivariate stepwise logistic regression analysis,smoking (OR=1.931,95% CI:1.000-3.731),family history of cancer (OR=5.175,95% CI:1.216-22.022),and duration of symptoms >10 years (OR=2.348 95% CI:1.394-3.952) were independent factors.CONCLUSION:Smoking,family history of cancer and duration of symptoms >10 years may be risk factors for ICC in patients with hepatolithiasis.

Risk Factors of Low Back Pain among the Chinese Occupational Population:A Case-control Study

Objective To explore the risk factors of low back pain among the Chinese occupational population in several major industries. Methods A total of 7200 subjects （3600 cases and 3600 controls） were randomly sampled from a cross-sectional study, and they were investigated for individual and occupational factors of low back pain. The potential risk factors were first selected by using chi-square tests. Secondly, collinearity diagnosis proceeded by using the Kendall＇s rank correlation. Finally, binary logistic regression model was used for multi-factor analysis. Results Collinearity diagnosis showed that there was a severe collinearity problem among the potential risk factors of low back pain. Logistic regression model included 20 variables with statistical significance. Bending neck forward or holding neck in a forward posturefor long periods （0R=1.408） was the most important risk factor inducing low back pain in this study, followed by bending heavily with the trunk （0R=1.402）, carrying out identical work almost for the whole day （0R=1.340）. Additionally, suHicient normal break was a protective factor of low back pain. Conclusion Low back pain among the Chinese occupational population was associated with body height, occupation, work organization, physical work, working posture, and others. All these risk factors could be regarded as the indicators of low back pain, and some relevant preventive measures should be taken to reduce low back pain risk.

Environmental and Psycho-social Factors Related to Prostate Cancer Risk in the Chinese Population:a Case-control Study

Objective To study the risk environmental and psycho-social factors associated to prostate cancer （PCa） in Chinese population. Methods 250 PCa patients and 500 controls were enrolled in this case-control study. Information was collected and logistic regression analysis was used to estimate the odds ratios （OR） and 95% confidence intervals （95% CI） for relationship between lifestyle, eating habits and psycho-social factors with PCa risk. Results Green vegetables and green tea were associated with a decreased risk of PCa （0R=0.39, 95% CI： 0.28-0.53; 0R=0.59, 95% Cl： 0.40-0.87, respectively）. Family history of PCa （0R=7.16, 95% CI： 2.01-25.49）, history of prostate diseases （0R=2.28, 95% Cl： 1.53-3.41）, alcohol consumption （0R=1.97, 95% CI： 1.33-2.90）, red meat consumption （0R=1.74, 95% CI： 1.20-2.52）, barbecued （0R=2.29, 95% CI： 1.11-4.73） or fried （0R=2.35, 95% CI： 1.24-4.43） foods were related with increased PCa risk. Negative psycho-social factors including occupational setbacks （0R=1.61, 95% CI： 2.00-2.59）, marital separation （0R=1.94, 95% CI： 1.29-2.91）, self-contained suffering {0R=2.37, 95% CI： 1.58-3.55）, and high sensitivity to the personal comments （0R=1.73, 95% CI： 1.18-2.54） were related to PCa. Conclusion Regular consumption of green vegetables and green tea may suggest protective effects on PCa. Alcohol consumption, red meat consumption and barbecued or fried foods were associated with PCa. Negative psycho-social factors may also play a role in the incidence of PCa in Chinese population.

Risk factors for the occurrence of insulinoma: a case-control study

BACKGROUND: The etiology of insulinoma is poorly understood. Few studies investigated the possible roles of environmental factors and lifestyle in the pathogenesis of insulinoma. The aim of this study is to identify risk factors associated with occurrence of insulinoma in the Chinese population. METHODS: This study consisted of 196 patients with insulinoma and 233 controls. Demographic information of the patients and controls and risk factors of the disease were analyzed. Univariate and unconditional multivariable logistic regression analyses were made to estimate odds ratios (ORs) and possible risk factors. RESULTS: Approximately 68.88% (135/196) of the patients were from rural areas in contrast to 10.30% (24/233) of the controls (P【0.0001). This difference was confirmed by the multivariate analysis (OR=4.950; 95% CI: 2.928-8.370). Family history of pancreatic endocrine tumor (OR=16.754; 95% CI: 2.125-132.057) and other cancers (OR=2.360; 95% CI: 1.052-5.291) was also related to a high-risk population of insulinoma. CONCLUSION: Rural residents or people who have a family history of pancreatic endocrine tumor and other cancers are a high-risk population of insulinoma.

Socio-maternal risk factors of ADHD among Iraqi children: A case-control study

Background: Attention-deficit hyperactivity disorder (ADHD) is a chronic disorder that appears first in childhood at preschool age (4 - 5) years, and is manifested by a symptomatic pattern of difficulties with attention, motor activity and impulsivity. Maternal factors like stress, socio-demographic and maternal life style factors are potential risk factors for ADHD. Methodology: A retrospective case-control study was conducted in Baghdad-Iraq. Cases have been taken from 5 private paediatric clinics. Controls were chosen from kindergartens within the same residential area of the paediatric private clinics. Mothers of cases and controls were investigated for the risk factors of ADHD using a self-administered questionnaire. The total sample size was 260. Number of cases was 130 and number of controls was 130. Results: Five variables were significantly associated with development of ADHD after using a multivariate logistic regression model, maternal war stress (Adjusted OR 9.08, 95% CI 4.70 - 17.52 and P value < 0.001), maternal smoking (Adjusted OR 3.27 95% CI 1.40 - 7.63, P < 0.001), father lost job (Adjusted OR 2.81, 95% CI 1.51 - 5.24, P value < 0.001), and house damaged (Adjusted OR 2.55, 95% CI 1.04 - 6.24, P < 0.05). Family income was also associated with risk of ADHD (OR 1.02 95% CI 1.00 - 3.12, P value < 0.05). Conclusion and suggestion: Maternal exposure to war stress has 9 times higher risk of developing ADHD among offspring. This study aimed to offer to the policy makers a good benchmark to plan more programmes related to women and child health with respect to the fourth and fifth Millennium Development Goals (MDGs) in reduction of child mortality and morbidity and improvement of maternal health. There is a real necessity to address the need of vulnerable pregnant mothers at war and disaster’s time for programmes which will be able to control the stress that those pregnant mothers would encounter during those hard times.

Periodontal disease is associated with increased coronary heart disease risk:A meta-analysis based on 38 case-control studies

AIM: To investigate whether periodontal disease(PD) is associated with increasing coronary heart disease(CHD) risk by performing a meta-analysis.METHODS: Two authors independently searched Pub Med and China National Knowledge Infrastructure up to January 10 th, 2013 for relevant case-control studies that investigated the association between PD and CHD. After quality assessment using Newcastle-Ottawa Scale and data extraction by two independent authors, the overall and subgroup meta-analyses were performed and publication bias were examined using the Comprehensive Meta-Analysis V2 software. Potential publication bias was assessed using visual inspection of the funnel plots, Egger linear regression test, and trims and fill method.RESULTS: Finally 38 relevant case-control studies were identified, involving 4950 CHD patients and 5490 controls. Eleven studies were rated low quality and 27 were high quality. Based on random-effects, a significant association was identified between PD and CHD(OR 3.79, 95%CI: 2.23-6.43, P < 0.001, I2 = 98.59%), and sensitivity analysis showed that this result was robust. Subgroup analyses according to adjusted/unadjusted ORs, source of control, methodological quality, end point, assessment of PD/CHD, and ethnicity also indicated a significant association. Publication bias was detected, and the estimated OR including the "missing" studies did not substantially differ from our estimate with adjustment for missing studies(OR 4.15, 95%CI: 2.62-6.54, P < 0.001).CONCLUSION: Based on the meta-analysis, PD is probably associated with CHD risk independently and significantly.

Risk Factors for Low Birth Weight and Preterm Birth：A Population-based Case-control Study in Wuhan,China

Low birth weight（LBW） and preterm birth（PB） are associated with newborn mortality and diseases in adulthood.We explored factors related to LBW and PB by conducting a population-based case-control study from January 2011 to December 2013 in Wuhan,China.A total of 337 LBW newborn babies,472 PB babies,and 708 babies with normal birth weights and born from term pregnancies were included in this study.Information of newborns and their parents was collected by trained investigators using questionnaires and referring to medical records.Univariate and logistic regression analyses with the stepwise selection method were used to determine the associations of related factors with LBW and PB.Results showed that maternal hypertension（OR=6.78,95% CI：2.27–20.29,P=0.001）,maternal high-risk pregnancy（OR=1.53,95% CI：1.06–2.21,P=0.022）,and maternal fruit intake ≥300 g per day during the first trimester（OR=1.70,95% CI：1.17–2.45,P=0.005） were associated with LBW.BMI ≥24 kg/m^2 of mother prior to delivery（OR=0.48,95% CI：0.32–0.74,P=0.001） and gestation ≥37 weeks（OR=0.01,95% CI：0.00–0.02,P〈0.034） were protective factors for LBW.Maternal hypertension（OR=3.36,95% CI：1.26–8.98,P=0.016）,maternal high-risk pregnancy（OR=4.38,95% CI：3.26–5.88,P〈0.001）,maternal meal intake of only twice per day（OR=1.88,95% CI：1.10–3.20,P=0.021）,and mother liking food with lots of aginomoto and salt（OR=1.60,95% CI：1.02–2.51,P=0.040） were risk factors for PB.BMI ≥24 kg/m^2 of mother prior to delivery（OR=0.66,95% CI：0.47–0.93,P=0.018）,distance of house from road ≥36 meters（OR=0.72,95% CI：0.53– 0.97,P=0.028）,and living in rural area（OR= 0.60,95% CI：0.37–0.99,P=0.047） were protective factors for PB.Our study demonstrated some risk factors and protective factors for LBW and PB,and provided valuable information for the prevention of the conditions among newborns.

A Case-control Study on High-risk Factors for Newborn Hearing Loss in Seven Cities of Shandong Province

To investigate the high-risk factors for newborn hearing loss and to provide information for preventing the development of hearing loss and delaying its progression, from May 2003 to June 2006, neonates who failed to pass the universal newborn hearing screening （UNHS） were referred to Jinan Newborn Hearing Screening and Rehabilitation Center from 7 newborn hearing screening centers in seven cities of Shandong province. One-to-one pair-matched case-control method was employed for statistical analysis of the basic features of definitely identified cases. High-risk factors relating to the bilateral hearing loss were evaluated by univariate and multivariate Logistic regression analysis. Our results revealed that 721 transferred newborns who didn＇t pass the heating screening received audiological and medical evaluation and 367 were confirmed to have hearing loss. Of them, 177 neonates with hearing loss who met the matching requirements were included in the study as subjects. Univariate analysis showed that high-risk factors related to hearing loss incuded age of father, education backgrounds of parents, parity, birth weight, gestational weeks, craniofacial deformity, history of receiving treatment in neonatal intensive care unit （NICU）, neonatal disease, family history of otopathy and family history of congenital hearing loss. Multivariate Logistic regression analysis revealed that 4 independent risk factors were related to bilateral hearing loss, including parity （OR=16.285, 95% CI 3.379--78,481）, neonatal disease （OR=34;968, 95% CI 2.720 449.534）, family history of congenital hearing loss （OR=69.488, 95% CI 4.417--1093.300） and birth weight （OR=0.241, 95% CI 0.090--0.648）. It is concluded that parity, neonatal disease and family history of heating loss are the promoting factors of bilateral hearing loss in neonates and appropriate intervention measures should be taken to deal with the risk factors.

Risk Factors for Birth Defects: A Conditional LogisticRegression Analysis of a Case-Control Study in Guang-dong Province of China

Information was obtained from the same questionnaire (23 risk factors listed) of cases and controls. We used a multivariate logistic model, which described variables significantly increased risk of birth defects. The risk factors included maternal educational levels, medicine taken during pregnancy and antenatal care. It was suggested to strengthen antenatal care was the main preventive measure against birth defects.

A Case-Control Study of Obstetric Fistula Risk Factors in the Democratic Republic of the Congo

Background: Pregnant women in the Democratic Republic of Congo (DRC) are at increased risk for developing obstetric fistulas (OFs) as a result of obstructed labor, in conditions similar to many other African countries. No case-control study of biological and social risk factors for OF has been reported from the DRC. This study aimed to identify factors that would aid in prevention and early identification of women who are at risk of developing OF. Methods: Participants were enrolled in a case-control study at four obstetric clinics in the central DRC. Cases of OF were evaluated as they presented, then a control participant was enrolled among women presenting subsequently to the same clinic, seeking to match parity at the time of the fistula and tribe of the case. A questionnaire was administered to elicit physical, obstetric, demographic, socioeconomic, religion, geographic, and delivery attributes of the participants. Case-control comparisons sought to identify independent risk factors for OF in the total case-control pairs and in subgroups of the participants. Logistic regression was utilized to identify independent risk factors for OF in the total case-control study group and in selected subgroups of the participants, and linear regression was utilized to estimate the variation explained between case and control outcomes from the variables independently significant in the logistic regression models. Results: A total of 177 case-control pairs were enrolled. Among all pairs, shorter height of the case (odds ratio = 1.06, 95% Confidence Limits 1.02 - 1.12);more kilometers travelled to the delivery site (1.02, 1.01 - 1.02);her village, not town, residence (OR = 5.52, 2.72 - 11.2), and her lower professional status (2.95, 1.53 - 5.72) were statistically independent factors associated with OF development. When applied in linear regression comparison of the pairs, these variables yielded an r2 = 0.48, imputing 48% of the difference in delivery outcome between the pairs was explained by these variables. Among the 38 pairs who were primigravida, the independent variables were more kilometers travelled to the delivery site (1.02, 1.00 - 1.05), village, not town, residence (50.0, 10.2 - 248.7), and facility intended for lower patient acuity (3.7 s, 1.01 - 13.6, r2 = 0.66) patients who were matched on parity and tribe, the significant risk factors were professional status (OR = 0.29), greater distance travelled to the clinic (OR = 1.02, 1.01 - 1.02), village, not town, residence (5.52, 2.72 - 11.2), and mother’s lower professional status (2.95, 1.53 - 5.72) when the OF occurred. Conclusions: Our study showed biological and social factors associated with the development of OF. Shorter height was the only biological risk factor found to be statistically significant in the study population. Other factors were related to limited resources and limited access to medical care.

Among the risk factors of myocardial infarction, anthropometry has no association: A case control study in the central region of Sri Lanka

Background: In the face of rising incidence of cardiovascular disease in the globe, the associated risk factors could be country or area specific. This study aimed to identify the important risk factors of myocardial infarction (MI) prevailing in the Kandydistrict of Sri Lanka. Methods: In a case control design, the cases were recruited from the Coronary Care Unit, General Hospital Kandy, with the diagnosis of myocardial infarction. Matched controls were selected from the Out Patient Department with other ailments, unrelated to cardiovascular diseases. Results: There were 205 cases and 197 controls with the mean age of 56 years (SD ± 8.4 years) and 54 years (SD ± 9.8 years) respectively with male: female ratio of 1:0.2. In analysis, hypertension (OR = 5.09, CI = 2.64 - 9.83), type 11 diabetes (OR = 3.45, CI = 1.90 - 6.10), smoking (OR = 1.95, CI= 1.44 - 2.65) and high LDL cholesterol levels (OR = 1.06, CI = 1.04 - 1.06) were identified as the independent risk factors of myocardial infarction. However, the anthropometric measurements, waist hip ratio (OR = 0.64, CI = 0.33 - 1.34) and body mass index ≥ 25 (OR = 0.75, CI = 0.46 - 1.22) did not show an association with myocardial infarctions. Conclusions: Anthropometric measurements did not qualify as risk factors of myocardial infarction in the local setting even though hypertension, diabetes, smoking and high LDL levels showed a significant association in par with the established data.

A case－control study on risk factors of stress fractures in military recruits during basic training

Stress fracture(SF) is an important training injury with a high incidence during recruits' basic training. In order to primarily investigate its risk factors and to provide etiologic threads for a further study,we carried out a case control study on SF. The results of univariate analysis and multivariate logistic regression analysis revealed that attending training on the occasion of injury or fatigue , and a lower length ratio of tibia and pelvic limb were the main risk factors of SF. The authors are of the opinion that compared with the absolute length of tibia , the relative length of tibia(tibia length/pelvic limb length) may be more relevant to the tibia biomechanical characteristics. , The harm of attending training under the circumstances of injury or fatigue is discussed in this paper.

Maternal and foetal risk factors of cerebral palsy among Iraqi children. A case control study

Background: The importance of studying cerebral palsy comes from the fact that, this disorder imposes huge burden families psychologically, emotionally, financially and socially. Moreover, it imposes a major burden on the National Health System because it is simply a chronic disorder, which needs a continuous care and multiple financial resources. At the same time, it needs collaborative efforts and team work between many parties and organizations for a good management and rehabilitation. In Iraq, risk factors of cerebral palsy have not been explored before. Our study objective was to measure the association between, maternal factors, foetal and early neonatal factors, and occurrence of cerebral palsy among Iraqi children. Postnatal risk factors of cerebral palsy were excluded in our study. Methods: We did a retrospective case-control study in Baghdad-Iraq. The place of study was The Central hospital of Children of Baghdad. Cases and controls were fully investtigated (retrospectively) for the risk factors of cerebral palsy using a self-administered questionnaire. The sample size was 300. Number of cases in our study was 100 while the number of controls in our study was 200. Results and conclusion: 84% of the mothers of Cerebral Palsy children were employed compared to 49% of the mothers of normal children who were employed (P value 0.00). After using a multiple logistic regression model, the final adjusted odd ratios included 6 variables which were, employment of mother (OR 8.05, 95% CI 0.98 - 6.62), Primigravida(OR 0.24, 95% CI 0.10 - 0.60), gender of the child(OR 0.15, 95% CI 0.04 - 0.51 ), asphyxia (OR 10.58, 95% CI 3.59 - 31.21), hypoglycemia (OR 40.99, 95% CI 6.93 - 242.27) and hypocalcaemia (OR 27.91, 95% CI 2.04 - 380.96). Our study came to a conclusion that neonatal asphyxia, hypoglycemia and hypocalcaemia were still the major risk factors for cerebral palsy In Iraq.

Extrinsic Risk Factors for Women Breast Cancer in Gaza Strip, Palestine: Associations and Interactions in a Case-Control Study

Background: Worldwide, breast cancer (BC) is the most frequently diagnosed neoplastic disease in women around menopause that is the leading cause of DALYs, because it causes a significant reduction of these women’s ability to function normally in everyday life. Methods: The present hospital-based case-control study was carried out between January and August 2018 using a structured questionnaire on 105 breast cancer women and 210 controls who are clinically free from breast cancer. Data about the study cases were collected in the oncology day-care clinics of the two main hospitals in Gaza strip “Al-Shifa and European Gaza hospitals”. Univariate logistic regression and multivariate logistic regression analyses were employed to identify the significant factors associated with BC. Results: Multivariate logistic regression analyses with adjustment for all confounders revealed that woman with BMI more than or equal 30 kg/m2 are under risk of getting BC 2.9 times greater than those having BMI less than 29 kg/m2 (AOR = 2.895;95% CI: 1.305 - 6.423). Analysis of risk according to reaching menopause showed that the estimated AOR was greater among those reached menopause (3.137, 95% CI 1.824 - 5.395) than among those that did not reach menopause. The risk of developing BC in the case of a history of incidence of BC in the family was more than two times higher (AOR = 2.632, 95% CI 1.528 - 4.535) than in case of the history of a free family of BC. Conclusion: In this context, the above-mentioned risk factors must be taken into consideration in BC management processes in the Gaza strip.

Association between Prenatal Environmental Factors and Child Autism: A Case Control Study in Tianjin,China

Objective To investigate the association between autism and prenatal environmental risk factors.Methods A case-control study was conducted among 193 children with autism from the specialeducational schools and 733 typical development controls matched by age and gender by usingquestionnaire in Tianjin from 2007 to 2012. Statistical analysis included quick unbiased efficientstatistical tree （QUEST） and logistic regression in SPSS 20.0.Results There were four predictors by QUEST and the logistic regression analysis, maternal airconditioner use during pregnancy （OR=0.316, 95% CI： 0.215-0.463） was the single first-level node（χ2=50.994, P=0.000）; newborn complications （OR=4.277, 95% CI： 2.314-7.908） and paternalconsumption of freshwater fish （OR=0.383, 95% CI： 0.256-0.573） were second-layer predictors（χ2=45.248, P=0.000; χ2=24.212, P=0.000）; and maternal depression （OR=4.822, 95% CI： 3.047-7.631）was the single third-level predictor （χ2=23.835, P=0.000）. The prediction accuracy of the tree was 89.2%.Conclusion The air conditioner use during pregnancy and paternal freshwater fish diet might bebeneficial for the prevention of autism, while newborn complications and maternal depression might bethe risk factors.

Risk of Active Pulmonary Tuberculosis among Patients with Coal Workers'Pneumoconiosis:A Case-control Study in China

The aim of this study was to estimate the association between occupational, environmental, behavioral risk factors, and active pulmonary tuberculosis（PTB） among coal workers＇ pneumoconiosis（CWP） patients. A matched case-control study was conducted in 86 CWP patients with active PTB and 86 CWP controls without TB. A standardized questionnaire was used for risk factors assessment. Conditioned logistic regression analysis was used to identify associations between the risk factors and active PTB among CWP patients. The results showed that the stage of CWP, poor workplace ventilation, family history of TB, and exposure to TB were independent risk factors for active PTB in patients with CWP with which recommendations for improving work environments, and for case finding activities in patients with CWP could be made.

Risk factors for Parkinson's disease and interaction analysis in Chinese patients

BACKGROUND： The etiology of Parkinson＇s disease （PD） remains unclear. The majority of studies have focused on the correlation between various factors and PD, with very different conclusions. To date, there has been no study on the interaction between PD family history and other risk factors, and very few studies have reported on hedtability. OBJECTIVE： To explore the risk factors for PD, the interaction between family history and other risk factors, and the impact of genetic factors on PD. DESIGN, TIME AND SETTNG： A paired, retrospective, case-control study was performed at the Department of Neurology, Qilu Hospital of Shandong University from November 2006 to October 2008. PARTICIPANTS： The case group included 157 Chinese PD patients selected from the Department of Neurology, Qilu Hospital of Shandong University in China from 2006 to 2008. An additional 157 patients treated in the same department during the same period were selected as the control group, and they were paired with regard to gender, age, and nationality to the case group. METHODS： Various scored factors were investigated in all participants. The association between various factors and PD was analyzed using univariate and multivariate logistic regression analysis. Interaction analysis between family history and other risk factors was performed using a logistic regression model. Heritability analysis was performed with the Falconer method. MAIN OUTCOME MEASURES： Risk factors for PD, interaction between family history and other risk factors, and heritability. RESULTS： Logistic regression analysis showed that family history, mental work, insecticide exposure, alcohol, and depression positively correlated with PD （odds ratio = 6.75, 2.37, 2.42, 2.03, 5.20, P〈 0.05）, whereas smoking had a negative correlation with PD （odds ratio = 0.49, P 〈 0.001）. The proportions of the effect attributable to interaction of family history and insecticide exposure, alcohol, and depression were 55.2%, 34.0%, and 41.4%, respectively, with a relative excess risk due to interaction of 8.96, 3.31, and 7.85, respectively. PD heritability from first-degree relatives was （36.86 ± 5.76） % and from second-degree relatives was （20.66 ± 6.81） %. CONCLUSION： Family history, mental work, insecticide exposure, alcohol, and depression were determined to be risk factors for PD, whereas smoking was a protective factor. Family history had a positive interaction with coexisting risk factors. Genetic factors had a smaller action on PD than environmental factors.

X-ray repair cross-complementing gene 1 Arg399Gln polymorphism and glioma risk among Asians A meta-analysis based on 2 326 cases and 3 610 controls

OBJECTIVE： Previous reports have demonstrated that X-ray repair cross-complementing gene 1 （XRCCl） Arg399GIn polymorphism is a possible risk factor for several cancers. Published data on the association of XRCCl Arg399GIn polymorphism with glioma susceptibility have generated conflicting results. This study is designed to precisely estimate the relationship. DATA RETRIEVAL： A computer-based online retrieval of Medline, EMBASE, OVID, Sciencedirect, and Chinese National Knowledge Infrastructure was performed to search papers regarding association of XRCC1 Arg399GIn polymorphisms with glioma published up to April 2012. SELECTION CRITERIA： Two investigators selected data independently. Meta analysis was then performed for the selected studies using STATA 11.0 software after strict selection. Heterogeneity test, sensitivity analysis and publication bias assessments were then conducted. MAIN OUTCOME MEASURES： Association of XRCCl Arg399GIn polymorphism with glioma risk. RESULTS： A total of nine case-controlled studies comprising 2 326 cases and 3 610 controls were selected for final analysis. The overall data failed to indicate a significant association of XRCCl Arg399GIn polymorphism with glioma risk （Gin/Gin vs. Arg/Arg： odds ratio （OR） = 1.11; 95% confidence interval （Cl） = 0.94-1.31; dominant model： OR = 1.06; 95%C/= 0.95-1.18; recessive model： OR = 1.04; 95%C/= 0.81-1.34）. However, subgroup analysis regarding ethnicity showed an increased risk among Asians （Gin/Gin vs. Arg/Arg OR = 1.40; 95%C/= 1.10-1.78; recessive model： Caucasians or mixed ethnicities. OR = 1.70; 95%Cl = 1.17-2.46; dominant mode OR = 1.46; 95%C/= 1.04-2.05） but not CONCLUSION： XRCCl Arg399GIn polymorphism might modify the susceptibility to glioma among Asians but not Caucasians. Further large and well-designed studies are needed to confirm this conclusion.