title: A meta-analysis of coffee intake and risk of urolithiasis.
abstract: OBJECTIVE
  Epidemiologic studies have reported various results relating coffee to urolithiasis. A meta-analysis of cohort and case-control studies was conducted to pool the relative risk (RR) estimates of the association between coffee and urolithiasis.
  
  
  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 RR estimates. A dose-response meta-analysis was performed for studies reporting categorical RR estimates for a series of exposure levels.
  
  
  RESULTS
  A total of 6 studies (2 cohort and 4 case-control studies) on coffee intake were included in the meta-analysis. The pooled odds ratio (OR) showed a significant influence of the highest coffee consumption (OR = 0.70, 95% confidence interval 0.60-0.82) on the risk of urolithiasis. Coffee exhibited an inverse dose-response relationship with urolithiasis. In stratified analysis, a significant inverse association between coffee and urolithiasis was observed in study design, geographical region and gender subgroup.
  
  
  CONCLUSIONS
  The overall current literature suggests that coffee intake is associated with a decreased risk of urolithiasis. Further efforts should be made to clarify the underlying biological mechanisms.
authors: Department of Urology, Zhejiang Provincial People's Hospital Affiliated to Zhejiang University, Hangzhou, P.R. China.
authors: Shuai
authors: S
authors: Wang
authors: Yuelong
authors: Y
authors: Zhang
authors: Zujie
authors: Z
authors: Mao
authors: Xiang
authors: X
authors: He
authors: Qi
authors: Q
authors: Zhang
authors: Dahong
authors: D
authors: Zhang
mesh_terms: D016009:Chi-Square Distribution; D003069:Coffee / Q000009:adverse effects; D006801:Humans; D008019:Life Style; D015999:Multivariate Analysis; D016017:Odds Ratio; D065840:Protective Factors; D018570:Risk Assessment; D012307:Risk Factors; D052878:Urolithiasis / Q000139:chemically induced / Q000175:diagnosis / Q000453:epidemiology / Q000517:prevention & control*
chemical_list: D003069:Coffee