Effects of Cough Training and Inspiratory Muscle Training on Cough Strength in Older Adults: A Randomized Controlled Trial.

ABSTRACT

PURPOSE: While the need for preventive strategies to reduce the incidence of aspiration pneumonia has been indicated, it is also important to investigate effective training methods to improve cough function, which is associated with the development of aspiration pneumonia. This study aimed to investigate whether a 4-week home-based unsupervised cough training (CT) or inspiratory muscle training (IMT) program was effective in improving cough strength in older adults. METHODS: Fifty-three ambulatory older adults without airflow limitations were randomly assigned to one of three groups a CT group (n = 18), an IMT group (n = 18), or a control group (n = 17). The CT and IMT groups performed home-based unsupervised training with a device for 4 weeks. Cough strength (cough peak flow), forced vital capacity, and respiratory muscle strength were assessed at the 4-week and 16-week follow-up. Intention-to-treat analyses were performed to investigate differences between the three groups using linear mixed models. RESULTS: At the 4-week follow-up, the CT group showed significant increases in cough peak flow and forced vital capacity compared with the control group, while the IMT group showed significant increases in inspiratory muscle strength compared with the cough training and control groups. At the 16-week follow-up, the CT group showed a significant increase in cough peak flow compared with the IMT group. CONCLUSION: These preliminary results suggest that a 4-week home-based CT program may have short-term effectiveness in improving cough peak flow in ambulatory older adults. TRIAL REGISTRATION This trial was registered on UMIN-CTR on 01/05/2018 (UMIN000031656).