Influence of Inspiratory Muscle Training on Respiratory Functions among Uncontrolled Asthmatics

Abstract

Background: Specific breathing exercises are reported to improve quality of life and reduce symptoms; although no significant benefit on lung function or reduction of exacerbation risk. Additionally, inspiratory muscle training (IMT) aims to increase diaphragm and inspiratory muscle endurance. In this regard, IMT has been studied in uncontrolled asthma patients to investigate its effect on respiratory symptoms and pulmonary functions. Methods: Twenty-one uncontrolled and partially controlled asthmatic patients were included in the study. Asthma control test (ACT), asthma quality of life questionnaire (AQLQ), and spirometric evaluations were performed. The study population was randomized into two groups. The standard care group (n=10) received standard medical treatment while the intervention (n=11) group practiced a portable threshold IMT device following standard medical treatment. Results: The study was completed by 15 patients due to 6 lost follow up (one intervention group and 5 standard care) and one asthma exacerbation. We have found that the intervention group tended to have increased pulmonary function test parameters and AQLQ scores, moreover; MIP values and ACT scores have statistically significant increases after IMT(p=0.01, p=0.02 respectively). Conclusion: Add-on IMT to standard medical treatment could improve asthma control by strengthening inspiratory muscles in uncontrolled asthmatic patients. IMT could be considered in the non-pharmacological treatments of uncontrolled asthmatic patients. Despite the limited number of patients, this study revealed that IMT might have positive outcomes for uncontrolled asthma patients.