title: Alcohol intake and risk of Parkinson's disease: a meta-analysis of observational studies.
abstract: BACKGROUND
  The association of alcohol intake with risk of Parkinson's disease remains unclear.
  
  
  METHODS
  Pertinent studies were identified in PubMed and EMBASE. The fixed-effect or random-effect model was selected based on heterogeneity. The dose-response relationship was assessed by restricted cubic splines.
  
  
  RESULTS
  We included 32 articles, involving 677,550 subjects (9994 cases). The smoking-adjusted risk of Parkinson's disease for the highest versus lowest level of alcohol intake was relative risk (RR) 0.78 (95% confidence interval [CI], 0.67-0.92) overall, 0.86 (95% CI, 0.75-0.995) in prospective studies, and 0.74 (95% CI, 0.58-0.96) in matched case-control studies. A significant association was found with beer (0.59; 95% CI, 0.39-0.90) but not with wine and liquor, and for males (0.65; 95% CI, 0.47-0.90) after a sensitivity analysis but not for females. The risk of Parkinson's disease decreased by 5% (0.95; 95% CI, 0.89-1.02) for every 1 drink/day increment in alcohol intake in a linear (Pfor nonlinearity  = 0.85) dose-response manner.
  
  
  CONCLUSIONS
  Alcohol intake, especially beer, might be inversely associated with risk of Parkinson's disease
authors.affiliation: Department of Epidemiology and Health Statistics, Qingdao University Medical College, Qingdao, P.R. China.
authors.forename: Dongfeng
authors.initials: D
authors.lastname: Zhang
authors.forename: Hong
authors.initials: H
authors.lastname: Jiang
authors.forename: Junxia
authors.initials: J
authors.lastname: Xie
mesh_terms: D000428:Alcohol Drinking / Q000009:adverse effects / Q000453:epidemiology*; D016206:Databases, Bibliographic / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D008297:Male; D010300:Parkinson Disease / Q000453:epidemiology*; D012306:Risk
keywords: Parkinson's disease; alcohol; meta-analysis; observational study