Factors associated with daily physical activity in patients with Pulmonary arterial hypertension

Background: Pulmonary arterial hypertension (PAH) reduces daily physical activity (DLPA) but the underlying mechanisms are not fully understood. The aim of this study was to evaluate DLPA and to determine its relationship to functional capacity and psychological factors in patients with PAH. Methods: This was a single-center prospective study of DLPA conducted in a Brazilian University hospital. Twenty stable PAH subjects mean age 44.3 ± 13.2 yrs, 80% Idiopathic PAH and 20% PAH associated to collagen disease, functional class (CF-NYHA I/II/III: N=7/10/3) completed a 7-day monitoring of daily walking steps by accelerometer and performed pulmonary function tests, 6-minute walk test (6MWT), 1-min sit-to-stand test (STST), and echocardiogram. They also answered 3 questionnaires (quality of life [SF-36], hospital anxiety and depression scale [HADS], and Manchester Respiratory Activities of Daily Living [MRADL]). Results: The mean number of daily steps was 4,280 ± 2,351, and the mean activity time was 41.6 ± 19.3minutes. The mean number of daily steps correlated positively (p Conclusion: DLPA is reduced in PAH and is associated to limitation of daily living activities, functional capacity and depression symptoms, but not with echo variables. These findings reinforce the multifactorial nature of exercise limitation in PAH. Also, they suggest that objective measurement of habitual activity might provide additive value in PAH assessment.