Prevalence of orthostatic hypotension in Parkinson’s disease: A systematic review and meta-analysis

BackgroundAlthough orthostatic hypotension (OH) is recognized as one of the main non-motor symptoms of Parkinson’s disease (PD), there is inconsistent evidence about the prevalence of OH in PD. To estimate the prevalence of OH in PD more precisely we conducted a systematic review of the literature.MethodsFrom PubMed and Embase searches with predefined inclusion criteria, we identified studies published up till December 2009. Prevalence numbers from studies were pooled using a non-linear random-effects meta-analysis.ResultsWe found 25 studies from which the prevalence of OH could be calculated. The pooled estimate of the point prevalence of OH in PD was 30·1% (95% CI: 22·9% to 38·4%). We found a large statistical heterogeneity between studies which could not be reduced by several subgroup analyses.ConclusionsThe estimated prevalence of OH in PD is 30%. However, due to the large heterogeneity between studies this pooled estimate should be interpreted with caution. More data from unselected population-based cohorts are needed.