Maximizing treatment response in patients with neuropathic-subtype postural orthostatic tachycardia syndrome

Postural Orthostatic Tachycardia Syndrome (POTS) is notoriously difficult to diagnose and successfully treat. POTS encompasses several different subtypes, but little research attention has focused on optimizing the diagnosis and treatment of specific subtypes. This study aims to identify variables potentially predictive of neuropathic POTS and determine which current medical therapies for POTS are most successful in the neuropathic population. Single-center retrospective review identified 382 patients diagnosed with POTS between 2018 and 2020. Diagnosis was established via the head-up tilt table test; neuropathic subtype was established via skin biopsy or quantitative sudomotor axon reflex test. Logistic regression identified variables predictive of the neuropathic subtype; Cox proportional hazard and Kaplan-Meier estimator modeling were employed to compare treatment response to medications between neuropathic and non-neuropathic patients. Patients with neuropathic POTS treated with ivabradine exhibited a median treatment response duration of 26.7 months in the neuropathic group vs. 10.7 months in the non-neuropathic group, reflecting a significantly reduced risk of treatment failure (hazard ratio = 0.273, = 0.028). No other studied treatments demonstrated different response. Of the clinical and demographic variables studied, only elevated baseline heart rate was significantly associated with the neuropathic POTS subtype, though with questionable clinical significance. Patients with neuropathic POTS may exhibit different medication treatment response compared to patients with non-neuropathic POTS, though prospective studies are needed for confirmation. Further study to identify optimal treatment regimens for different subtypes of POTS is a promising direction to improve the quality of care for patients with POTS.