Respiratory muscle training on pulmonary and swallowing function in patients with Huntingtons disease: A pilot randomised controlled trial

© SAGE Publications. Objective: To examine the effects of 4-month of respiratory muscle training on pulmonary and swallowing function, exercise capacity and dyspnoea in manifest patients with Huntingtons disease. Design: A pilot randomised controlled trial. Setting: Home based training program. Participants: Eighteen manifest Huntingtons disease patients with a positive genetic test and clinically verified disease expression, were randomly assigned to control group (n=9) and training group (n=9). Intervention: Both groups received home-based inspiratory (5 sets of 5 repetitions) and expiratory (5 sets of 5 repetitions) muscle training 6 times a week for 4 months. The control group used a fixed resistance of 9 centimeters of water, and the training group used a progressively increased resistance from 30% to 75% of each patients maximum respiratory pressure. Main measures: Spirometric indices, maximum inspiratory pressure, maximum expiratory pressure, six minutes walk test, dyspnoea, water-swallowing test and swallow quality of life questionnaire were assessed before, at 2 and 4 months after training. Results: The magnitude of increases in maximum inspiratory (d=2.9) and expiratory pressures (d=1.5), forced vital capacity (d=0.8), forced expiratory volume in 1 second (d=0.9) and peak expiratory flow (d=0.8) was substantially greater for the training group in comparison to the control group. Changes in swallowing function, dyspnoea and exercise capacity were small (d′0.5) for both groups without substantial differences between groups. Conclusions: A home-based respiratory muscle training program appeared to be beneficial to improve pulmonary function in manifest Huntington;euro™s disease patients but provided small effects on swallowing function, dyspnoea and exercise capacity.