Dysautonomia in Long COVID is Prevalent and Could Explain the Frequency of Symptoms.

Background: Long COVID presents with a variety of symptoms, some of which could be related to autonomic dysfunction. Our aim was to evaluate the prevalence of autonomic dysfunction in long COVID patients.Methods: We conducted a cross-sectional study and included all consecutive patients enrolled in several clinical research studies. We performed the following autonomic dysfunction markers: heart rate variability, heart rate, systolic and diastolic blood pressure changes during NASA Lean Test, cardiopulmonary exercise testing and a Composite-Autonomic-Symptom-Score (COMPASS)-31 scale. We used linear regression to calculate the contribution of each dysautonomia measure on symptom burden as measured by the modified COVID-19 Yorkshire scale.Results: We included 100 patients for this study. Our sample population had a mean age of 56+/-11 years, included 53% minorities, and 32% were women. Dysautonomia, as defined by an abnormal COMPASS-31, was seen in 82% (95% confidence interval [CI] 72-89) of our study population, while cardiovascular resting dysautonomia, as represented by an abnormal heart rate variability, was seen in 60% (95% CI 48-70) of our study population. Orthostatic hypotension was observed in 12% of our study population, and postural orthostatic tachycardia syndrome (POTS) was found in 10% of our study population. In our adjusted analysis, we found that the beta coefficient for the COMPASS-31 score (0.37) was significant on changes in a self-reported long COVID symptom burden. The orthostatic intolerance and gastrointestinal domains of the COMPASS-31 were associated with the highest long COVID symptom burden.Conclusion: Dysautonomia is common in long COVID patients and contributes to the overall symptoms seen in long COVID. Identifying dysautonomia has important diagnostic and therapeutic implications.