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 riskof urolithiasis. Further efforts should be made to clarify the underlying biological mechanisms.