POSTPRANDIAL HYPOTENSION IN MSA AND PD WITH AUTONOMIC FAILURE

Introduction Postprandial hypotension is often reported in Parkinson’s disease with autonomic failure (PD+AF) and Multiple System Atrophy (MSA). However there has been no study directly comparing this feature between these two disorders. The aim of this study was to evaluate cardiovascular autonomic responses before and after standard liquid meal ingestion in PD+AF and MSA. Methods Patients underwent a liquid meal challenge using a previously described protocol. Blood pressure (BP) and heart rate (HR) were measured at intervals. All participants remained supine for 45 min after the liquid meal ingestion. They underwent 10 min head-up tilt (HUT) to 60° before and 45 min after the meal. Results 22 MSA and 11 PD+AF patients were identified. Supine post-prandial hypotension was significantly more common in PD+AF compared to MSA (73% vs 36%; p 0.05). Conclusion Despite the similar degree of orthostatic hypotension on supine and HUT, postprandial hypotension is more commonly present in patients with PD+AF compared to MSA. The increased tendency to post-prandial hypotension even while supine reflects the nature of post-ganglionic sympathetic denervation in PD.