Association Between COVID-19 and Orthostatic Intolerance in Children: A Retrospective Study

Introduction SARS-CoV-2 infection (COVID-19) and the COVID-19 vaccine have been linked to the development of persistent symptoms, including orthostatic intolerance (OI) and postural orthostatic tachycardia syndrome (POTS), in both children and adults. POTS is characterized by excessive tachycardia and other symptoms upon standing, significantly impacting quality of life. This study aims to evaluate the clinical and laboratory findings in pediatric patients with post-COVID-19 or post-COVID-19 vaccine OI and POTS. Methods This retrospective chart review included pediatric patients under 18 years of age with chronic dizziness or syncope following COVID-19 infection or vaccination. Autonomic studies, including the tilt table test, Valsalva maneuver, deep breathing test, and Quantitative Sudomotor Axon Reflex Test (QSART), were conducted to assess autonomic function. Data on clinical symptoms, autonomic testing results, and sweat production were collected and analyzed. Results In total, 16 patients (mean age 15 ± 3 years) were included in the study, with 14 patients developing symptoms post-COVID-19 infection and two post-vaccination. Ten patients (62.5%) met the criteria for POTS, with an average delta heart rate of 49 bpm on tilt table testing. Seven patients (43.75%) showed abnormal results on the Valsalva maneuver, and 50% (four patients) of those who underwent QSART demonstrated small fiber neuropathy. The mean standing norepinephrine level was 520 picograms per milliliter (pg/mL), with some patients showing markedly elevated levels. Conclusion This study highlights the growing incidence of POTS and other forms of OI in pediatric patients following COVID-19 infection and vaccination, supporting the link between COVID-19 and autonomic dysfunction in children. Our findings contribute to the growing body of literature on Long-COVID and emphasize the need for greater awareness, as well as further research into its long-term autonomic effects.