A Feasibility Study of a Randomized Controlled Trial of Asthma-Tailored Pulmonary Rehabilitation Compared with Usual Care in Adults with Severe Asthma.

Abstract

Currently, the acceptability and efficacy of pulmonary rehabilitation for adults with severe asthma is unknown. To investigate the feasibility of performing a randomized controlled trial of asthma-tailored pulmonary rehabilitation (AT-PR) versus usual care (UC). Adults with severe asthma were recruited and randomized 2:1 to AT-PR and UC. The primary outcomes were recruitment, retention, and serious adverse event rates. Secondary outcome measures included those for a future trial assessing the feasibility of collecting data. Assessments were performed at baseline, 12 weeks, and 9 months including measures of physical performance, health-related quality of life, and asthma control. A recruitment rate of 30% was estimated with 95% CI of ±7%, a retention rate of 75% ± 14% if we recruited 40 patients to AT-PR, and a serious adverse event rate of 2.5%. Sixty-one (26%) of 238 eligible patients were recruited (38 women; mean age, 54 ± 13 years; body mass index, 32 ± 7 kg/m²; FEV₁, 1.9 ± 0.7 L; FEV₁/forced vital capacity, 69% ± 11%). Fifty-one patients were randomized to AT-PR (n = 34) and UC (n = 17). The retention rate was 62% for the AT-PR group and 53% for the UC group, with a serious adverse event rate of 3.3% related to the study visits. Overall collection of the outcome measures was feasible. The results of the AT-PR group were suggestive of improvements in exercise performance, health-related quality of life, and asthma control, but the UC group results were either unchanged or worsened. Both recruitment and retention rates were within the a priori estimated 95% CI. Our results indicate that AT-PR may be efficacious for adults with severe asthma but any future intervention and trial design would need further modifications to improve acceptability and retention rate.