Effectiveness of a Pulmonary Rehabilitation Program on Persistent Asthma Stratified for Severity

BACKGROUND: Asthma is defined by airway inflammation associated with various respiratory symptoms, and pharmacologic treatment is based on inhaled corticosteroids and bronchodilators. Physical activity, educational training, nutritional support, and psychological counseling are considered part of non-pharmacologic treatment; however, studies so far have investigated the effect of single non-pharmacologic treatment. There are few studies that demonstrate the effect of comprehensive pulmonary rehabilitation, but no clear data are available regarding factors that can predict who could benefit the most. Our study aimed to assess the effect of a comprehensive 3-week pulmonary rehabilitation program on exercise tolerance and to identify baseline subject characteristics that may predict a better response to treatment. METHODS: This was a retrospective study. A team planned a pulmonary rehabilitation program: educational support; endurance training; and optional components, such as respiratory exercises and airway clearance techniques. The following data were collected before and after pulmonary rehabilitation: subject characteristics, smoking history, asthma severity, respiratory function and 6-min walk test (6MWT). RESULTS: We collected data on 515 subjects (202 males 39.2%), age, mean ± SD 63.9 ± 10.4 y), with 413 (80.2%) having moderate-to-severe disease; and 455 (88.4%) with stable respiratory symptoms 455 (88.35%). At baseline, the percentage of predicted 6MWT in all subjects categorized by the Global Initiative for Asthma (GINA) steps was in the normal range, except for the subjects at step 5, for which it was significantly lower (P = .01). All subjects showed a significant improvement in exercise tolerance and oxygen saturation, together with a decrease in baseline dyspnea, muscle fatigue, and heart rate after pulmonary rehabilitation. Improvement of 6MWT was statistically significant, irrespective of the GINA categorization. The variables related to the improvement in 6MWT were age (P < .001), smoking habit (P = .034), and baseline 6MWT (P < .001). CONCLUSIONS: Subjects with asthma at any GINA step seemed to benefit from a pulmonary rehabilitation program; analysis of our data highlighted that pulmonary rehabilitation was more beneficial in younger subjects with a smoking history and worse baseline exercise tolerance.