Reduced Risk of Parkinson's Disease in Users of Calcium Channel Blockers: A Meta-Analysis.

Aim. To pool the data currently available to determine the association between calcium channel blockers (CCBs) and risk of Parkinson's disease (PD). Methods. Literature search in PubMed, EBSCO, and Cochrane library was undertaken through March 2014, looking for observational studies evaluating the association between CCBs use and PD. Pooled relative risk (RR) estimates and 95% confidence intervals (CIs) were calculated using random-effects model. Subgroup analyses, sensitivity Analysis, and cumulative meta-analysis were also performed. Results. Six studies were included in our meta-analysis according to the selection criteria, including three cohort studies and three case-control studies involving 27,67,990 subjects including 11,941 PD cases. We found CCBs use was associated with significant decreased risk of PD, compared with not using CCBs (random effects model pooled RR, 0.81 (95% CI, 0.69-0.95)); a significant heterogeneity was found between studies (P = 0.031; I (2) 54.6%). Both the classes of CCB, that is, dihydropyridine calcium channel blockers (DiCCB) (0.80 (95% CI, 0.65-0.98) P = 0.032) and non-DiCCB (0.70 (95% CI, 0.53-0.92) P = 0.013), were found to be reducing the risk of PD. Conclusion. In our analysis, we found that CCBs use was associated with a Significantly decreased risk of PD compared with non-CCB use.