POTS-CFS Study: Orthostatic Intolerance in the Context of Pediatric ME/CFS

ME/CFS is a complex disease. Symptoms include orthostatic intolerance (OI) such as postural tachycardia syndrome (PoTS). PoTS in ME/CFS can significantly impair everyday function and social participation. Yet, data in affected adolescents are rare and inconsistent. This pilot-case-control study study aimed at characterizing OI in adolescents aged 14-17 years with ME/CFS and age-adapted HC, comparing the results with other clinical features of both such as exertion intolerance, fatigue, and health-related quality of life, and suggesting a standardized tool for diagnostics. ME/CFS was diagnosed according to the Clinical Canadian Criteria (CCC 2003), criteria of the former Institute of Medicine (IOM 2015), the diagnostic work sheet developed by Rowe 2017, and/or the pediatric case suggested by Jason 2006. Questionnaires were used to evaluate symptoms (e.g. post-exertional malaise, fatigue, anxiety, depression), and health-related quality of life. A standardized specific interview was performed to assess the medical history of OI (HOI). Heart rate (HR) and blood pressure were evaluated every minute during a passive 10-min standing test (NASA lean test) in the morning with empty stomach and without morning medication. Data were evaluated according to the PoTS criteria defined in 2019 at the National Institutes of Health Expert Consensus Meeting and by the International Classification of Diseases (ICD-11) (8D89.2). Frequency and type of OI, including PoTS, were examined in both groups and outcomes compared to parameters from questionnaires. Based on the results, novel standards for OI diagnostics were suggested.