Peripheral autonomic failure is associated with more severe postprandial hypotension compared to central autonomic failure

PURPOSE: Postprandial hypotension (PPH) defined as a decrease in systolic blood pressure of more than 20 mmHg within 2 h post meal is prevalent in patients with autonomic failure and is associated with negative cardiovascular outcomes. Previous studies reported peripheral autonomic failure with less residual sympathetic tone in Parkinson disease (PD). Therefore, we hypothesized that PPH is more severe in PD than in multiple system atrophy (MSA) with central autonomic failure. METHODS: Thirteen patients with PD and 13 patients with MSA were enrolled. Autonomic function testing and neurohormonal measurements were performed to assess autonomic failure and residual sympathetic activity. Subjects were fed a standard breakfast. Systolic and diastolic blood pressure and heart rate were monitored every 5 min from 30 min before to 120 min post meal. Postprandial hemodynamic changes were summarized using area under the curve (AUC). Differences between the groups were assessed with two-sample independent t test and linear regression. RESULTS: Patients with PD (69% male, 72 ± 9 years) had a significantly lower post-meal diastolic blood pressure (P = 0.003) and heart rate AUC (P = 0.007) than patients with MSA (62% male, 62 ± 8 years). After adjusting for age and supine systolic blood pressure, PD as diagnosis still had significant estimate effect for diastolic blood pressure AUC (P = 0.019). No significant difference was found in the mean systolic blood pressure AUC, but at 30 min post meal, systolic blood pressure decrease was significantly lower in PD (P = 0.016). CONCLUSION: The PD group with peripheral autonomic failure exhibits more severe PPH than the MSA group. This highlights the need for tailored management for PPH in PD.