The effects of pulmonary rehabilitation combined with inspiratory muscle training on pulmonary function and inspiratory muscle strength in elderly patients with chronic obstructive pulmonary disease

It has been suggested that pulmonary rehabilitation compined with inspiratory muscle training (IMT) might improve pulmonary function and respiratory muscle strength in elderly patients with chronic obstructive pulmonary disease (COPD). To test this hypothesis, inspiratory muscle strength (PImax), expiratory muscle strength (PEmax) and resting pulmonary function were measured in 13 elderly patients with COPD (aged 70.3 ± 2.7 years). Inspiratory muscle training (IMT) was performed for 15 min twice a day, using a pressure threshold device, for a total of 12 weeks. The inspiratory threshold was set at 15% of maximal inspiratory pressure (PImax) for each individual. Pulmonary rehabilitation was performed for 12-h sessions over a 12-week period. Patients with COPD were assigned randomly to two groups: pulmonary rehabilitation combined with IMT (group A) (n=7), and conventional pulmonary rehabilitation only (group B) (n=6). Functional residual capacity (FRC) decreased significantly from 4.3 ± 0.4 L at baseline to 3.9 ± 0.4 L after rehabilitation (p<0.01), V̇p significantly increased from 4.6 ± 0.8 L/sec at baseline to 5.1 ± 0.7 L/sec after rehabilitation (p < 0.05) and the PImax increased significantly from 51.5 ± 5.4 cmH₂O at baseline to 80.9 ± 7.0 cmH₂ O after rehabilitation (p<0.02) in group A. However, these variables did not change in group B. There was no improvement in the 10-minutes walking distance of group A, but there was a significant increase in that of group B. It can be concluded that pulmonary rehabilitation combined with IMT improves pulmonary function and inspiratory muscle strength in elderly patients with COPD.