title: Body Mass Index Can Increase the Risk of Gallbladder Cancer: A Meta-Analysis of 14 Cohort Studies.
abstract: BACKGROUND This study sought to appraise the association between raised body mass index (BMI) and the risk of gallbladder cancer (GBC) by performing a meta-analysis of 14 cohort studies. MATERIAL AND METHODS Eligible cohort studies were selected by searching PubMed and EMBASE from their inception to May 26, 2016, and the reference lists of retrieved articles were also consulted. The information was screened by two authors separately. We used a fixed-effects model to calculate the overall pooled risk estimates. A random-effects model was used to identify heterogeneity. RESULTS The meta-analysis incorporated 14 cohort studies. Nine papers were deemed to be of high quality based on the Newcastle-Ottawa Scale (NOS). Compared with normal weight (BMI 18.5-24.9 kg/m²), the overall pooled relative risks (RR) of GBC was 1.45 (95% CI 1.30-1.61) for excess body weight individuals (BMI ≥25 kg/m²); 1.10 (95% CI 1.02-1.18) for overweight persons (BMI 25-29.9 kg/m²) and 1.69(95% CI 1.54-1.86) for obese folks (BMI ≥30 kg/m²). A higher risk of GBC was presented in obese women (women: RR 1.78, 95% CI 1.59-1.99; men: RR 1.50, 95% CI 1.25-1.79). And a positive relationship between overweight and GBC risk was also displayed in female (RR 1.25, 95% CI 1.11-1.40), but not in male (RR 1.01, 95% CI 0.93-1.11). The sensitivity analysis indicated stable results, and no publication bias was observed. CONCLUSIONS This meta-analysis of 14 cohort studies demonstrated that raised BMI has a dramatic association with risk of GBC, especially in women. But, no association between overweight and GBC in men was found.
authors.affiliation: Department of General Surgery, The 6th Affiliated Hospital of Kunming Medical University, The People's Hospital of Yuxi City, Yuxi, Yunan, China (mainland).
authors.forename: Hao
authors.initials: H
authors.lastname: Liu
authors.affiliation: Department of General Surgery, The 6th Affiliated Hospital of Kunming Medical University, The People's Hospital of Yuxi City, Yuxi, Yunan, China (mainland).
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Health Statistics and Epidemiology, Dali University, Dali, Yunnan, China (mainland).
authors.forename: Min
authors.initials: M
authors.lastname: Ai
authors.affiliation: Department of General Surgery, The 6th Affiliated Hospital of Kunming Medical University, The People's Hospital of Yuxi City, Yuxi, Yunan, China (mainland).
authors.forename: Jun
authors.initials: J
authors.lastname: Wang
authors.affiliation: Department of General Surgery, The 6th Affiliated Hospital of Kunming Medical University, Yuxi, Yunan, China (mainland).
authors.forename: Bo
authors.initials: B
authors.lastname: Jin
authors.affiliation: Department of Orthopedic Surgery, The 6th Affiliated Hospital of Kunming Medical University, The People's Hospital of Yuxi City, Yuxi, Yunan, China (mainland).
authors.forename: Zhaowei
authors.initials: Z
authors.lastname: Teng
authors.affiliation: Department of General Surgery, The 6th Affiliated Hospital of Kunming Medical University, The People's Hospital of Yuxi City, Yuxi, Yunan, China (mainland).
authors.forename: Yansheng
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of General Surgery, The 6th Affiliated Hospital of Kunming Medical University, The People's Hospital of Yuxi City, Yuxi, Yunan, China (mainland).
authors.forename: Li
authors.initials: L
authors.lastname: Li
mesh_terms: D015992:Body Mass Index; D001835:Body Weight; D015331:Cohort Studies; D005260:Female; D005706:Gallbladder Neoplasms / Q000453:epidemiology*; D006801:Humans; D008297:Male; D009765:Obesity / Q000453:epidemiology*; D050177:Overweight / Q000453:epidemiology; D012307:Risk Factors; D012737:Sex Factors