Inspiratory muscle training, with or without concomitant pulmonary rehabilitation, for chronic obstructive pulmonary disease (COPD)
Omar Ammous, Walid Feki, Tamara Lotfi, Assem M. Khamis, Rik Gosselink, Ahmed Rebaï, Samy Kammoun
Abstract
BACKGROUND: Inspiratory muscle training (IMT) aims to improve respiratory muscle strength and endurance. Clinical trials used various training protocols, devices and respiratory measurements to check the effectiveness of this intervention. The current guidelines reported a possible advantage of IMT, particularly in people with respiratory muscle weakness. However, it remains unclear to what extent IMT is clinically beneficial, especially when associated with pulmonary rehabilitation (PR). OBJECTIVES: To assess the effect of inspiratory muscle training (IMT) on chronic obstructive pulmonary disease (COPD), as a stand-alone intervention and when combined with pulmonary rehabilitation (PR). SEARCH METHODS: We searched the Cochrane Airways trials register, CENTRAL, MEDLINE, Embase, PsycINFO, Cumulative Index to Nursing and Allied Health Literature (CINAHL) EBSCO, Physiotherapy Evidence Database (PEDro) ClinicalTrials.gov, and the World Health Organization International Clinical Trials Registry Platform on 20 October 2021. We also checked reference lists of all primary studies and review articles. SELECTION CRITERIA: We included randomized controlled trials (RCTs) that compared IMT in combination with PR versus PR alone and IMT versus control/sham. We included different types of IMT irrespective of the mode of delivery. We excluded trials that used resistive devices without controlling the breathing pattern or a training load of less than 30% of maximal inspiratory pressure (PImax), or both. DATA COLLECTION AND ANALYSIS: O, 95% CI 9.85 to 19.29; 32 RCTs, 916 participants; low-certainty evidence). In subgroup analysis, we did not find a difference between different training durations and between studies judged with and without respiratory muscle weakness. None of the included RCTs reported adverse events. AUTHORS' CONCLUSIONS: IMT may not improve dyspnea, functional exercise capacity and life quality when associated with PR. However, IMT is likely to improve these outcomes when provided alone. For both interventions, a larger effect in participants with respiratory muscle weakness and with longer training durations is still to be confirmed.