To examine burden of autonomic symptoms over two years among patients with the neuropathic subtype of Postural Orthostatic Tachycardia Syndrome (POTS).

POTS is a heterogeneous autonomic clinical condition in which patients experience orthostatic intolerance and abnormal tachycardia. The neuropathic POTS subtype is prevalent in 30-50% of patients and is associated with autonomic and somatosensory nerve dysfunction. Longitudinal evaluation of autonomic burden in neuropathic POTS remains unexplored. Our current study presents findings from a tertiary care center.

We conducted a retrospective chart review of 211 POTS patients who underwent quantitative sudomotor axon reflex testing (QSART) to evaluate for small fiber neuropathy at Cleveland Clinic between January 2018 and January 2021. The 31-item Composite Autonomic Symptom Score questionnaire (COMPASS-31) examined patient profiles at the initial presentation and two years later. Patients without COMPASS-31 scores or positive QSART were excluded from the study. Other variables, such as medications, were examined. Improvement was defined by reduction of COMPASS-31 score. Statistical analyses, including paired t-tests, were employed to evaluate COMPASS-31 change.

Among 211 POTS, only thirteen met our inclusion criteria. At initial presentation, thirteen patients reported high burden of autonomic symptoms (median COMPASS-31 score of 50.5 (IQR: 24.46-58.56), but after two years, there was no improvement (median score of 48.5 IQR: 11.57-56). The patients tried several medications, including pyridostigmine (9) and beta-blockers (6). Lifestyle changes included fluid hydration (12) and high-sodium diets (10). Many patients continued to experience high levels of anxiety (11), depression (9), and gastrointestinal issues (10), and seven of them stopped working.