Disability and its clinical correlates in pulmonary hypertension measured through the World Health Organization Disability Assessment Schedule 2.0: a prospective, observational study

Objective: To characterise the degree of disability in pulmonary hypertension (PH) patients based on the World Health Organisation Disability Assessment Schedule 2.0 (WHODAS 2.0). Method: A prospective and observational study of patients with documented PH (N = 46). Patients completed the WHODAS 2.0 questionnaire during a scheduled routine clinical visit, and their demographic and clinical characteristics were retrieved from electronic medical records (EMR). In subsequent visits, selected clinical variables were registered to assess disease progression. Results: WHODAS 2.0 scores were indicative of mild to moderate disability for the domains of mobility (22.0 +/- 23.2), life activities (23.7 +/- 25.5), and participation in society (17.2 +/- 15.9), as well as total WHODAS 2.0 score (15.3 +/- 15.2). For the domains of cognition (9.1 +/- 14.1), self-care (8.3 +/- 14.4), and interpersonal relationships (11.7 +/- 15.7), scores were lower. Disability scores were, generally, proportional to the PH severity. The main baseline correlates of disability were World Health Organisation (WHO) functional class, fatigue, dyspnoea, 6-minute walking distance (6MWD), and N-terminal pro b-type natriuretic peptide (NTproBNP). Baseline WHODAS 2.0 scores showed significant associations with disease progression. However, this effect was not transversal to all domains, with only a few domains significantly associated with disease progression variables. Conclusions: This PH population shows mild disability, with higher degree of disability in the domains of mobility and life activities. This study is the first one to assess disability in PH using WHODAS 2.0. Further studies should apply this scale to larger PH populations with suitable representations of more severe PH forms.