Inspiratory Muscle Training for Asthmatic Patients: A Meta-Analysis of Randomized Controlled Studies

Abstract Introduction The efficacy of inspiratory muscle training (IMT) for asthma control remains controversial. We conduct a systematic review and meta-analysis to explore the influence of IMT on asthma control. Methods We search PubMed, EMbase, Web of science, EBSCO, and Cochrane library databases through May 2020 for randomized controlled trials (RCTs) assessing the efficacy of IMT for asthma control. This meta-analysis is performed using the random-effect model. Results Six RCTs are included in the meta-analysis. Overall, compared with control group for asthma, IMT can remarkably increase MIP (SMD=3.32; 95% CI=1.73 to 4.91; P<0.0001) and decrease dyspnea scores (SMD=−0.77; 95% CI=−1.34 to −0.21; P=0.007), but has no obvious effect on FEV1 (SMD=0.36; 95% CI=−0.74 to 1.45; P=0.52) or FVC (SMD=2.09; 95% CI=−0.70 to 4.89; P=0.14). Conclusions IMT may benefit to the treatment of asthma.