Effect of inspiratory muscle training in hemodialysis patients: a systematic review of randomized controlled trials

To clarify the effect of inspiratory muscle training on inspiratory muscle strength, lung function, and functional capacity in hemodialysis patients. Randomized controlled trials evaluating inspiratory muscle strength, lung function, and functional capacity in hemodialysis patients were searched. The search was conducted in Medline, Web of Science, and Scopus between August and December 2024. Risk of bias was assessed using the Cochrane Collaboration’s risk of bias tool-2. 316 Studies were analyzed, and 12 were included, involving 460 patients. The intervention consisted of training the respiratory muscles using linear loading devices, varying between 30% and 70% of Maximum Inspiratory Pressure, for 4 to 24 weeks. One study was classified as high risk of bias, three with some concerns, and eight low risk of bias. Inspiratory muscle strength increased significantly in the intervention groups. Significant changes concerning lung function were observed only in some groups. Considerable variations in the distance covered in the 6-MWT test were also found in some studies. Inspiratory muscle training appears to influence several outcomes. Replicating randomized controlled trials with standardized protocols and robust assessment methods is necessary to more effectively establish their effectiveness. Inspiratory muscle training has proven scientific evidence in several chronic diseases, is simple and safe, and has the advantage of being able to be performed during hemodialysis sessions. Hemodialysis patients’ often show changes in the strength of their inspiratory muscles due to the marked loss of muscle mass to which they are subjected. Inspiratory muscle training has been proposed as a non-pharmacological rehabilitation strategy to enhance respiratory muscle strength and lung function, with the clinical goals of reducing dyspnea, improving exercise tolerance, and promoting functional independence. A more comprehensive understanding of the multiple variables involved, such as training intensity, session frequency, duration, type of device, respiratory muscle strength, exercise tolerance, and individual clinical factors, is necessary.