Multimorbidity, functional impairment and health-related quality of life in postural orthostatic tachycardia syndrome: findings from an Australian observational cohort study

Abstract

Abstract Objectives To characterise the symptom, comorbidity and diagnostic journey of adult and older adolescent patients with postural orthostatic tachycardia syndrome (POTS). Design Cross-sectional observational cohort study. Setting Participants ≥16 years old with physician-confirmed POTS who enrolled in the Australian POTS registry between 1 May 2021 and 30 April 2024 were included. Participants 500 participants enrolled in the Australian POTS registry. Outcome measures Health-related quality of life and symptom severity were assessed using validated patient-reported outcome measures, including the Composite Autonomic Symptom Score, EuroQol 5-Dimension-5 Level (EQ-5D), Gastroparesis Cardinal Symptom Index (GCSI), Fatigue Severity Scale (FSS) and the 5-point hypermobility index scores. Sociodemographics, diagnostic journey details and comorbidities were obtained via self-reported questionnaires and reconciled with medical records by the clinical team. Results Among 500 participants (86.8% females, 92.7% White; mean age 31.3±11.7 years), the median diagnostic delay was 3.0 years (IQR 9.0; mean 6.7 years), with 25.5% experiencing a delay of ≥10 years. Despite being young and highly educated, 22.0% were unemployed or unable to attend education. Infection was the most frequently identified proximal trigger and accounted for 39.4% of cases. Higher autonomic symptom burden, as reported on the Composite Autonomic Symptoms Score (COMPASS-31) questionnaire, was associated with greater fatigue (FSS: 56.0±8.8 vs 48.0±14.5; p<0.001), gastrointestinal symptoms (GCSI: 1.60±0.77 vs 0.89±0.63; p<0.001), increased healthcare utilisation and worse quality of life (EQ-5D utility: 0.547±0.237 vs 0.717±0.200; p<0.001), assessed using Mann-Whitney U and χ2 tests as appropriate. Conclusions POTS is associated with significant diagnostic delays, high healthcare utilisation, substantial symptom burden, educational, social and occupational impacts. Patient-reported outcome measures such as the COMPASS-31 questionnaire can assist in identifying high-risk individuals. Systemic healthcare reform is urgently needed to improve access to timely diagnosis and effective treatment for individuals living with POTS. Trial registration number ACTRN12621001034820.