High-Intensity Respiratory Muscle Training in Individuals With Parkinson's Disease

Background: Individuals with PD commonly have a significant reduction in respiratory muscle strength and inspiratory muscle endurance, and it can intensify with the disease progression. Respiratory muscle training has shown to increase respiratory muscle strength in individuals with Parkinson's Disease (PD). However, the effect size on other functional outcomes has not been determined and/or investigated. In addition, no studies have investigated the effects of high-intensity respiratory muscle training (inspiratory and expiratory) in this population.Objectives: The primary aim of this study will be to investigate the effects of high-intensity respiratory muscle training on inspiratory and expiratory muscle strength in individuals with PD. The secondary aim of this study will be to investigate the efficacy of high-intensity respiratory muscle training in improving inspiratory muscle endurance, peak cough flow, dyspnea, fatigue, exercise capacity, and quality of life in this population.Design: A randomized controlled trial with blinded assessment will assign eligible participants to either: high-intensity respiratory muscle training (experimental group) or sham training (control group). Individuals will perform a home-based intervention, not directly supervised, consisted of two daily 20-min sessions (morning and afternoon), seven times a week, during eight weeks.Study Outcomes: Primary outcomes are inspiratory and expiratory muscle strength (MIP and MEP). Secondary outcomes are respiratory muscle endurance, peak cough flow, dyspnea, fatigue, exercise capacity, and quality of life.The outcomes will be measured at baseline, post-intervention (after the 8-week intervention), and one month after the cessation of the intervention (12-week follow-up).Conclusion: The results of this trial will provide valuable new information on the efficacy of high-intensity respiratory muscle training in improving muscle strength and other functional outcomes in individuals with PD.

Inclusion Criteria:Parkinson's disease diagnosed by a neurologistAbility to walk independently, with or without assistive devicesTaking anti parkinsonian medication, and who have been medically stable for at least six monthsClassified between stages 1-3 of the modified Hoehn & Yahr Scale (Schenkman et al., 2001)Maximum inspiratory pressure less or equal to -80 cmH2O or maximum expiratory pressure less or equal to 90 cmH2OExclusion Criteria:Possible cognitive impairment as determined by cutoff scores (in points) of the Mini-Mental Status ExaminationUse deep brain stimulation (DBS)Smokers or who stopped smoking less than six months ago; have been affected by respiratory or cardiac infections in the last monthHad any other neurological, musculoskeletal, cardiovascular or respiratory disorders that could affect their ability to perform the tests