1433-P: Association of Diabetes Status with Autonomic Dysfunction on ANSAR Testing in Patients with POTS and PSWT

Introduction and Objective: Postural Orthostatic Tachycardia Syndrome (POTS) and Postural Symptoms without Tachycardia (PSWT) are disorders of the autonomic nervous system that may be exacerbated by diabetes, as chronic hyperglycemia contributes to neuropathy and endothelial dysfunction. Autonomic Nervous System Assessment and Response (ANSAR) testing evaluates autonomic function by measuring heart rate responses during standardized physiologic maneuvers. This study evaluated whether a higher glycemic burden, assessed by diabetes status and HbA1c, is associated with greater autonomic dysfunction on ANSAR testing among patients with POTS or PSWT. Methods: A retrospective cross-sectional analysis was conducted of a random sample of 150 patients diagnosed with POTS or PSWT by tilt table testing. Diabetes status was categorized using medical history and HbA1c. Autonomic function was assessed using ANSAR testing and classified as normal or mildly abnormal. Associations were evaluated using chi-square testing. Results: Of the 150 patients included, 111 (74%) were diagnosed with POTS and 39 (26%) with PSWT. Overall, 64 patients (43%) had no diabetes, 26 (17%) had prediabetes, and 60 (40%) had diabetes. In POTS patients, abnormal ANSAR findings were observed in 9% of those without diabetes, 13% with prediabetes, and 27% with diabetes. In the PSWT subgroup, abnormal ANSAR findings occurred in 10% of patients without diabetes, 40% with prediabetes, and 53% with diabetes. No significant association was observed between diabetes status and ANSAR abnormalities in POTS (p = 0.064) or PSWT (p = 0.080). Conclusion: In patients with POTS and PSWT, diabetes status was not significantly associated with ANSAR abnormalities, despite a higher frequency of mild abnormalities among patients with diabetes, highlighting the need for further studies to clarify additional contributors to autonomic impairment.