Effectiveness of Respiratory Muscle Training on Respiratory Muscle Strength, Pulmonary Function, and Respiratory Complications in Stroke Survivors: A Systematic Review of Randomized Controlled Trials

Background Stroke is the most common leading cause of mortality and related morbidities worldwide. After stroke, the motor function of extremities and spinal muscles is significantly impairment, but not only this, it also has attributable factors leading to respiratory dysfunction. Nevertheless, to the extent of the authors’ knowledge, there is a dearth of conclusive studies which examined the effectiveness of RMT on muscle strength, pulmonary function, and respiratory complications of individuals after stroke. Objective The purpose of this systematic review was to evaluate the effectiveness of respiratory muscle training on respiratory muscle strength, pulmonary function, and respiratory complications in patients after stroke. Methods An electronic database search of HINARI, PEDro, PubMed, Cochrane Library and Google scholar was used to identify randomized controlled trials that evaluated the effectiveness of respiratory muscle training in patients with stroke. Articles published from 2010 to 2019 were included. The quality of the articles was assessed using PEDro scale. Articles with abstract only, PEDro scores less than 5, published in non-English language, not freely available articles, and quasi experimental studies were excluded from this study. Results The literature search yielded a total of 7 articles (6 randomized controlled trials with 1 pilot randomized controlled trial) which met inclusion criteria despite their heterogeneity. The methodological quality of all studies ranged from 6 to 8 in Pedro score. Most of the articles reported a significant increase in respiratory muscle strength, respiratory muscle function, and reduced risk of complications with a p value <0.05. Conclusion Respiratory muscle training could potentially improve muscle strength and pulmonary functions of subjects after stroke. Thus, it may reduce stroke-related respiratory complications in subjects after stroke. However, further study is warranted with high quality RCTs and pooled synthesis of results.