Abstract
We investigated whether the use of calcium channel blockers (CCBs) was associated with a reduced risk of Parkinson's disease (PD) in two large prospective cohorts: the Nurses' Health Study (NHS) and Health Professionals' Follow-Up Study (HPFS). Cox proportional hazards models were used to estimate relative risks (RRs) and 95% confidence intervals (CIs) to assess the association between use of CCBs and risk of PD adjusting for potential confounders. We identified 514 incident cases of PD during follow-up. No association between baseline use of CCBs (RR = 1.18, 95% CI: 0.73-1.92), frequency of use or duration of use of CCBs and PD risk was observed (P > 0.2 for all). These findings do not support a role for CCBs in providing neuroprotection against development of PD.