Cardiovascular Adverse Events Reported in Placebo Arm of Randomized Controlled Trials in Parkinson's Disease

Parkinson's disease and cardiovascular disease are highly prevalent conditions in the elderly. Evidence shows inconsistent findings regarding the association between Parkinson's disease and cardiovascular events.

We sought to evaluate the proportion of cardiovascular adverse events among Parkinson's disease patients included in the placebo arm of randomized controlled trials.

For this systematic review and meta-analysis, we searched MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials from inception to February 2017. Randomized, placebo-controlled trials in Parkinson's disease were included. The primary outcome was the proportion of major cardiovascular adverse events, defined as myocardial infarction, stroke, peripheral artery disease, and sudden death. A random-effects meta-analysis was performed to derive pooled estimates of the proportion of adverse events and corresponding 95% confidence intervals (CIs).

236 randomized controlled trials were included, 80% (n = 189; 14704 patients) of which reported data on cardiovascular adverse events. The pooled proportion of major cardiovascular events ranged from 0.00% to 0.06% and the proportion of all cardiovascular adverse events was 3.33% (95% CI: 2.14, 4.70%), and ranged from 1.71% in de novo Parkinson's disease patients to 4.56% in patients receiving levodopa as their only antiparkinsonian medication. The most common adverse events were hypertension and orthostatic hypotension.

These results suggest that the proportion of major cardiovascular adverse events is low and that blood pressure abnormalities are the most frequent cardiovascular adverse event.