Effects of Inspiratory Muscle Training in Patients With Bronchiectasis

Inspiratory muscle training is reportedly beneficial in patients with diverse chronic cardio-pulmonary diseases. It can increase inspiratory muscle strength and endurance, improves exercise capacity and quality of life (QOL), and decreases the perception of dyspnea (POD) for adults with stable chronic obstructive pulmonary disease (COPD). Though the pathophysiology in COPD and bronchiectasis are different, there are some similarities in clinical presentation. In COPD patients, lung hyperinflation induces functional weakness of the inspiratory muscle and increases elastic load to breathing and intrinsic positive end expiratory pressure. Patients with bronchiectasis shows reduced ratio of FEV1/FVC, reduced FEV1, and normal or slightly reduced FVC, which indicate that airways are blocked by mucus. However, there has been no study that used IMT as a training modality to determine its effect in bronchiectasis. The clinical relevance of increased respiratory muscle strength per se by IMT alone is unknown. This study tried to evaluate the feasibility and effectiveness of home-based threshold training and examined if the effects of IMT extends to clinical outcomes such as activities of daily living and QOL in bronchiectasis patients.