Abstract
AIM: Systematically quantifying the prevalence and incidence of orthostatic hypotension in Parkinson's disease patients. BACKGROUND: Orthostatic hypotension is a common non-motor symptom in Parkinson's disease patients. Although systematic reviews have been published previously, existing data are outdated, and there is a lack of research examining differences in the prevalence and incidence of this symptom across various etiologies. An update of current studies is urgently needed. DESIGN: Systematic review and meta-analysis. METHODS: A systematic search was conducted across the following databases: Medline, PubMed, Web of Science, Embase, Cochrane Library, CINAHL, and ProQuest, retrieving English-language publications since each database's inception. Included studies comprised cross-sectional, retrospective cohort, and prospective cohort investigations reporting the prevalence or incidence of orthostatic hypotension in patients with Parkinson's disease. RESULTS: This meta-analysis included 55 studies involving 10,463 patients with Parkinson's disease. The combined prevalence of orthostatic hypotension (OH) was 33% (95%CI, 28-37%), with high heterogeneity among studies (I (2) = 96%). Subgroup analysis revealed a significantly higher prevalence in males (24%) compared to females (12%). Regionally, Europe reported the highest prevalence (42%), followed by Asia (32%) and North America (28%). Prevalence rates obtained using active standing blood pressure measurement (33%) were slightly higher than those measured via tilt table testing (28%). The combined prevalence of neurogenic orthostatic hypotension was 26%. The prevalence of symptomatic and asymptomatic orthostatic hypotension was similar (20 and 22%, respectively). Meta-regression analysis indicated that mean patient age was the primary factor explaining heterogeneity between studies (adjusted τ (2) reduced by 94.9%), while disease duration, MDS-UPDRS- III score, and mean levodopa equivalent daily dose showed no significant association with orthostatic hypotension prevalence. However, it must be emphasized that these findings may be constrained by significant heterogeneity among studies, inconsistencies in variable definitions and measurement methods across included studies, and the limited number of available data points for regression analysis. Publication bias analysis suggested a small-sample effect; after adjustment using trimmed and inflated methods, the estimated prevalence decreased to 24.9%. CONCLUSION: Orthostatic hypotension is prevalent in Parkinson's disease with a combined prevalence of 33%, exhibiting considerable heterogeneity. This heterogeneity stems from variations in clinical practice and research methodologies. Our meta-analysis revealed that, at the pooled level, the prevalence of orthostatic hypotension showed no significant association with disease duration, MDS-UPDRS-III score and mean levodopa equivalent daily dose. However, this likely reflects inconsistencies in case definitions, timing of measurements, and measurement settings. Future studies must employ standardized autonomic assessment methods to accurately define neurogenic orthostatic hypotension and identify reliable clinical correlates. SYSTEMATIC REVIEW REGISTRATION: https://www.crd.york.ac.uk/PROSPERO/view/CRD42025632838, identifier PROSPERO (CRD42025632838).