Longitudinal prevalence of neurogenic orthostatic hypotension in the idiopathic Parkinson Progression Marker Initiative (PPMI) cohort

Abstract

AbstractBackgroundReported orthostatic hypotension (OH) prevalence in Parkinson disease (PD) varies widely, with few studies evaluating specifically neurogenic-OH (nOH). The ratio of orthostatic heart rate (HR) to systolic blood pressure (SBP) change (Δ) is a valid screening method to stratify nOH/non-nOH but had minimal epidemiologic application.ObjectiveTo estimate the prevalence of nOH and non-nOH in the PPMI using the ΔHR/ΔSBP ratio and examine associations between nOH and various motor and non-motor measures.MethodsLongitudinal orthostatic vitals and motor and non-motor measures were extracted (baseline-month 48). Patients were consensus criteria classified as OH+/-, with ΔHR/ΔSBP sub-classification to nOH (ΔHR/ΔSBP<0.5) or non-nOH (ratio≥0.5). Prevalence was determined across visits. Independent linear mixed models tested associations between nOH/non-nOH and clinical variables.ResultsOf N=907 PD with baseline orthostatic vitals, 3.9% and 1.8% exhibited nOH and non-nOH, respectively. Prevalence of nOH/non-nOH increased yearly (P=0.012, chi-square), though with modest magnitude (baseline: 5.6% [95% CI: 4.3-7.3%]; month 48: 8.6% [6.4-11.5%]). nOH patients were older than PD with no OH and nOH was associated with greater impairment of motor and independent functioning than non-nOH/OH-groups. Cognitive function and typical OH symptoms were worse in PD+OH, generally.ConclusionsnOH prevalence was greater than non-nOH in the PPMI early PD cohort, with modest prevalence increase over time. Our findings are consistent with prior studies of larges cohorts that evaluated nOH, specifically. Early PD with nOH were likelier to be older and suffer from greater motor and functional impairment, but OH presence was generally associated with more cognitive impairment.