What is the effect of home-based, high-intensity, combined inspiratory and expiratory muscle training on maximal respiratory pressures, inspiratory muscle endurance, peak cough flow, dyspnoea, fatigue, exercise capacity and quality of life in people with Parkinson's disease? A randomised controlled trial with concealed allocation, intention-to-treat analysis and blinding of participants, assessors and statisticians. People with Parkinson’s disease. The experimental group received high-intensity combined inspiratory and expiratory muscle training at 60% of maximal inspiratory pressure (MIP) and 60% of maximal expiratory pressure (MEP). The control group received sham training using the same protocol, but without any resistive load. Both groups trained for 20 minutes, twice per day, 7 days/week for 8 weeks. The primary outcome was respiratory muscle strength (MIP and MEP). Secondary outcomes included inspiratory muscle endurance, peak cough flow, dyspnoea (0-to-4 Medical Research Council scale, where lower scores are better), fatigue (1-to-7 Fatigue Severity, where lower scores are better), exercise capacity (6-minute walk test) and quality of life (0-to-100 Parkinson’s Disease Questionnaire-39, where lower scores are better). All outcomes were measured at 0, 8 and 12 weeks. Thirty-four participants were included. Compared with control, the experimental group had better MIP (MD 20 cmH 2 O, 95% CI 10 to 30), MEP (MD 24 cmH 2 O, 95% CI 10 to 39) and inspiratory muscle endurance (MD 1.2 minutes, 95%CI 0.4 to 2.0). The benefits in MIP and inspiratory muscle endurance were maintained at follow-up. Benefits also occurred in dyspnoea (MD –0.71, 95% CI –1.30 to –0.12) and exercise capacity (MD 24.9 m, 95% CI 0.2 to 49.7); however, the confidence intervals spanned worthwhile and trivial effects, indicating uncertainty about whether those effects are clinically worthwhile. High-intensity combined inspiratory and expiratory muscle training improved respiratory muscle strength, inspiratory muscle endurance, dyspnoea and exercise capacity in people with Parkinson’s disease. NCT05608941.
Brito et al. (Wed,) studied this question.