Factors Associated with Orthostatic Hypotension in Parkinson's Disease Patients: A Systematic Review and Meta-analysis

Orthostatic hypotension (OH) is a prevalent non-motor symptom in Parkinson's disease (PD), heightening the risk of falls and mortality. This study aimed to identify and quantify the factors associated with OH in PD patients. A comprehensive search of nine databases, PubMed, CINAHL, Web of Science, Scopus, Cochrane Library, Embase, China National Knowledge Infrastructure (CNKI), China Biology Medicine (CBM), and Wanfang, was conducted, covering articles from database inception to November 27, 2024. Two researchers independently screened titles, abstracts, and full texts, evaluating the methodological quality of the studies. Relevant data were analyzed through meta-analysis using R software. Nineteen studies of moderate to high quality were included. The analysis revealed significant associations between PD-related OH and several independent factors: age (OR = 1.06; 95% CI: 1.05-1.08; I² = 78%; P < 0.01), Hoehn-Yahr stage (H-Y stage) (OR = 1.57; 95% CI: 1.09-2.26; I² = 51%; P = 0.02), Hemoglobin A1c (HbA1c) (OR = 2.08; 95% CI: 1.28-3.38; I² = 0%; P < 0.01), REM Sleep Behavior Disorder (RBD) (OR = 5.83; 95% CI: 2.70-12.61; I² = 24%; P < 0.01), Levodopa-equivalent daily dose (LEDD) (OR = 1.00; 95% CI: 1.00-1.01; I² = 79%; P = 0.06), PD-autonomic dysfunction (SCOPA-AUT) (OR = 1.15; 95% CI: 0.99-1.34; I² = 94%; P = 0.06), and hypertension (OR = 3.86; 95% CI: 1.25-11.90; I² = 71%; P = 0.02). These findings suggest that factors such as age, H-Y stage, HbA1c, LEDD, SCOPA-AUT, hypertension, and RBD are associated with PD-related OH. Further research is essential to refine prevention strategies.