Characteristics of individuals with moderate to severe asthma who better respond to aerobic training: a cluster analysis

Objective: This study aimed to determine the characteristics of individuals with moderate to severe asthma responsive to aerobic training. Methods: We evaluated 101 individuals with moderate to severe asthma who underwent aerobic training in previous randomized controlled trials. The maximal cardiopulmonary exercise test (CPET) variables, Asthma Control Questionnaire (ACQ), and Asthma Quality of Life Questionnaire (AQLQ) were evaluated before and after 24 sessions of aerobic training, based on the CPET. Hierarchical cluster analysis was used to identify better responders and poor responders. Results: Two clusters were identified according to improvement in peak VO2: better responders and poor responders to aerobic training. The better responders9 group (66.3%) consisted of older individuals, females with a higher body mass index and cardiac reserve than the poor responder group at baseline. At baseline, better responders also presented worse clinical control and quality of life and lowered physical capacity than the poor responders. After training, the better responders showed twice the improvement in peak VO2 related to pre-intervention and in asthma control compared to poor responders. A weak negative association (r=-0.35;p<0.05) was observed between clinical control and aerobic fitness. Both groups presented an increase in aerobic fitness and a clinically significant improvement in the AQLQ score. Conclusion: Obese individuals with worse exercise capacity, clinical control, and quality of life showed a greater improvement with aerobic training. Poor responders also improved with training, but to a lesser extent.