Statin use and non-melanoma skin cancer risk: a meta-analysis of randomized controlled trials and observational studies

BACKGROUND: Existing evidence of the association between statin use and non-melanoma skin cancer (NMSC) risk has been inconsistent. OBJECTIVE: To maximize statistical power to synthesize prospective evidence on this relationship. MATERIALS AND METHODS: PubMed, EMBASE, Web of Science, Cochrane Central Register of Controlled Trials, and ClinicalTrial.gov were systematically searched up to December 11, 2016. A random-effects meta-analysis was conducted to calculate summary estimates. RESULTS: Our meta-analysis of 14 randomized controlled trials (RCTs) including 63,157 subjects showed no significant association between statin use and NMSC risk (RR = 1.09, 95%CI = 0.85–1.39). However, meta-analysis of four observational studies including 1,528,215 participants showed significantly increased risk of NMSC among statin users compared to non-users (RR = 1.11, 95%CI = 1.02–1.22). Furthermore, ever using lipophilic statins (RR = 1.14, 95%CI = 1.04–1.24) or lower-potency statins (RR = 1.14, 95%CI = 1.03–1.26), as well as usage of any statin longer than one year (RR = 1.14, 95%CI = 1.09–1.18) were significantly associated with increased NMSC risk based on observational studies. CONCLUSIONS: Evidence from observational studies supported an association between statin use and increased NMSC risk. This finding should be interpreted with caution due to modest number of included studies, possible between-study heterogeneity and inherent limitations of observational studies.