Statin use and risk of Parkinson's disease: A meta-analysis

Background and aim: Recent studies have suggested that use of statins was associated with risk of Parkinson's disease (PD), however, conclusions were inconsistent. Methods: A comprehensive literature search of PubMed, Web of Science, EMBASE and Cochrane Library was performed through March 2015. Studies that evaluated the association between statin use and risk of PD were included in this meta-analysis. Combined relative risk (RR) estimates and 95% confidence intervals (CIs) were calculated using a random-effects model. Subgroup analyses were also conducted. Results: A total of 11 studies(2,787,249 patients) were included for meta-analysis(5 case-control and 6 cohort studies). Our results indicated a significant risk reduction of PD(adjusted RR, 0.74, 95% CI 0.62-0.90, P < 0.001) for statin users. However, long-term statin use(RR 0.77, 95% CI 0.56-1.07, P = 0.12) and baseline low-density lipoprotein cholesterol(LDL-C) level(RR 0.58, 95% CI 0.31-1.07, P = 0.08) did not significantly affect the risk of PD. Heterogeneity and publication bias was observed in this meta-analysis (I-2=74%, P<0.001). Subgroup analysis showed that the difference of the study location can partly affected the pooled estimate(Asian population n=2, adjusted RR, 0.67; 95% CI, 0.56-0.79; Western population n=9, adjusted RR, 0.87; 95% CI, 0.80-0.95). Conclusions: Our meta-analysis suggested that statin use is associated with a reduced risk of PD. Statins might be considered as an adjuvant therapy for PD. More randomized clinical trials and observational studies are warranted. (C) 2016 Elsevier B.V. All rights reserved.