title: A meta-analysis of alcohol intake and risk of bladder cancer.
abstract: OBJECTIVE
  Epidemiologic studies have reported conflicting results relating alcohol intake to bladder cancer risk. A meta-analysis of cohort and case-control studies was conducted to pool the risk estimates of the association between alcohol intake and bladder cancer.
  
  
  METHODS
  Eligible studies were retrieved via both computer searches and review of references. We analyzed abstracted data with random effects models to obtain the summary risk estimates. Dose-response meta-analysis was performed for studies reporting categorical risk estimates for a series of exposure levels.
  
  
  RESULTS
  Nineteen studies met the inclusion criteria of the meta-analysis. No association with bladder cancer was observed in either overall alcohol intake group (OR = 1.00, 95% CI 0.89-1.10) or subgroups stratified by sex, study design, geographical region, or smoking status. However, in the analysis by specific beverages, both beer (OR = 0.86, 95% CI 0.76-0.96) and wine (OR = 0.85, 95% CI 0.71-1.00) consumption exhibited a negative dose-response relationship with bladder cancer.
  
  
  CONCLUSIONS
  The overall current literature on alcohol consumption and the risk of bladder cancer suggested no association, while the consumption of beer and wine was associated with reduced risk of bladder cancer. Further efforts should be made to confirm these findings and clarify the underlying biological mechanisms.
authors.affiliation: Department of Urology, The First Affiliated Hospital, School of Medicine, Zhejiang University, Qingchun Road 79, Hangzhou, 310003 Zhejiang, China.
authors.forename: Qiqi
authors.initials: Q
authors.lastname: Mao
authors.forename: Yiwei
authors.initials: Y
authors.lastname: Lin
authors.forename: Xiangyi
authors.initials: X
authors.lastname: Zheng
authors.forename: Jie
authors.initials: J
authors.lastname: Qin
authors.forename: Kai
authors.initials: K
authors.lastname: Yang
authors.forename: Liping
authors.initials: L
authors.lastname: Xie
mesh_terms: D000428:Alcohol Drinking / Q000009:adverse effects*; D001515:Beer; D016022:Case-Control Studies; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D015201:Meta-Analysis as Topic; D012306:Risk; D001749:Urinary Bladder Neoplasms / Q000453:epidemiology*; D014920:Wine