title: Statin use and risk of kidney cancer: a meta-analysis of observational studies and randomized trials.
abstract: OBJECTIVE
  Clinical studies have shown that statin use may modify the risk of kidney cancer. However, these studies yielded different results. To quantify the association between statin use and risk of kidney cancer, we performed a detailed meta-analysis of published studies regarding this subject.
  
  
  METHODS
  A literature search was carried out using MEDLINE, EMBASE and the Cochrane database between January 1966 and October 2012. Prior to performing a meta-analysis, the studies were evaluated for publication bias and heterogeneity. Fixed effect and random effect models were used to estimate summary relative risks (RR) and the corresponding 95% confidence intervals (CIs). Subgroup analyses and sensitivity analysis were also performed.
  
  
  RESULTS
  A total of 12 (two randomized controlled trials, five cohort, and five case-control) studies contributed to the analysis. There was heterogeneity among the studies but no evidence of publication bias. Pooled results indicated a non-significant decrease of total kidney cancer risk among all statin users (RR = 0.92, 95% CI 0.71, 1.19). Long term statin use did not significantly affect the risk of total kidney cancer (RR = 1.01, 95% CI 0.83, 1.22). In our subgroup analyses, the results were not substantially affected by study design, confounder adjustment and gender. Furthermore, sensitivity analysis confirmed the stability of the results.
  
  
  CONCLUSIONS
  The findings of this meta-analysis suggested that there was no association between statin use and risk of kidney cancer. More studies, especially randomized controlled trials and high quality cohort studies with larger sample size and well controlled confounding factors, are needed to confirm this association in the future.
authors.affiliation: Department of Urology, Shanghai Tenth People's Hospital, Tongji University, Shanghai, China; Department of First Clinical Medical College, Nanjing Medical University, Nanjing, China.
authors.forename: Xiao-long
authors.initials: XL
authors.lastname: Zhang
authors.forename: Min
authors.initials: M
authors.lastname: Liu
authors.forename: Jian
authors.initials: J
authors.lastname: Qian
authors.forename: Jun-hua
authors.initials: JH
authors.lastname: Zheng
authors.forename: Xiao-peng
authors.initials: XP
authors.lastname: Zhang
authors.forename: Chang-cheng
authors.initials: CC
authors.lastname: Guo
authors.forename: Jiang
authors.initials: J
authors.lastname: Geng
authors.forename: Bo
authors.initials: B
authors.lastname: Peng
authors.forename: Jian-ping
authors.initials: JP
authors.lastname: Che
authors.forename: Yan
authors.initials: Y
authors.lastname: Wu
mesh_terms: D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000009:adverse effects*; D007680:Kidney Neoplasms / Q000139:chemically induced* / Q000453:epidemiology; D064887:Observational Studies as Topic; D016017:Odds Ratio; D016032:Randomized Controlled Trials as Topic; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors
chemical_list: D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors
keywords: kidney cancer; meta-analysis; risk; statin