Inspiratory muscle training in addition to physical exercise for idiopathic pulmonary fibrosis

Abstract

Background: Inspiratory muscle training (IMT) has beneficial effects on dyspnoea, physical function and health related quality of life (HRQL) in patients with COPD but has not yet been evaluated in idiopathic pulmonary fibrosis (IPF). The aim of the study was to compare IMT and physical exercise (PE) with PE alone in patients with IPF.

Method: In a randomised controlled study, patients with IPF were randomised to IMT(n=14) or sham IMT(n=10) during an 8-week exercise programme. Exercise capacity was assessed with six minute walking test (6 MWT), respiratory muscle strength (PI,max, PE,max), dyspnea by modified Medical Council Scale and quality of life with Chronic respiratory disease questionnaire (CRQ-SAS) including the dimension of dyspnoea, at baseline and after 8 weeks PE. In addition, lung function test was measured.

Results: Patients performing IMT and PE had a significant reduction in the dimension dyspnoea of CRQ-SAS(p≤0.05) compared to controls. The IMT-group improved their walking distance from 466(±66) to 513(±102) m (p≤0.05), PI,max, from 90(±24) to 112(±29) cmH₂O (p≤0.001), PE,max, from 109(±27) to 121(±37) cmH₂O (p≤0.05). Fatigue (p≤0.05) and total score (p≤0.05) of CRQ-SAS was also improved. The IMT sham group improved significantly PI,max(p≤0.05) after eight weeks.

Conclusion: Inspiratory muscle training in combination with exercise in patients with IPF showed a significant improvement in dyspnoea compared with sham IMT and exercise. The study also showed a positive trend in favour of IMT in addition to exercise compared to exercise alone in exercise capacity, fatigue and HRQL in patients with IPF. IMT may therefore be a valuable addition to PE in patients with IPF.