Effect of breathing exercises on patients with interstitial lung disease: A systematic review and meta-analysis

This study was designed to synthesize the efficacy and safety of breathing exercises in interstitial lung disease (ILD) patients by reviewing the literature and comparing the impact of different control group types, ILD subtypes, breathing exercise action modes or methods, and intervention durations on clinical efficacy.

Systematic searches were conducted across 9 electronic databases, including PubMed, to retrieve English and Chinese studies reporting on ILD patients from inception to February 12, 2024. Study selection and data extraction were independently conducted by two researchers. The quality of the included studies was assessed using the Cochrane risk of bias tool. The data were analysed using RevMan 5.4 and STATA 17.0 software.

The search identified 25 studies. Compared to the control group, the breathing exercise group exhibited significantly improved lung function (FVC%pred: MD  =  3.46, 95%CI = 1.04 to 5.88; DLCO%pred: MD = 3.20, 95% CI = 2.91 to 3.48), dyspnoea (MRC or mMRC scale: MD = - 0.50, 95%CI = - 0.77 to - 0.22), exercise capacity (6MWD: MD = 32.65, 95% CI = 14.77 to 50.53), and HRQoL (SGRQ: MD = - 6.53, 95% CI = - 8.72 to - 4.34) in ILD patients. According to the subgroup analysis, significant improvements consistent with the overall results were observed in the control group with usual treatment. Compared with the control group, breathing exercises had varying degrees of improvement in the mixed diagnostic group, known-cause group, and fibrotic group of ILD patients; breathing exercises alone significantly improved DLCO%pred, MRC (or mMRC), and SGRQ; and the improvement in breathing exercises as part of pulmonary rehabilitation (PR) was more notable. Different durations of breathing exercise could promote the efficacy of different aspects of treatment for ILD patients.

Compared with usual treatment, breathing exercises can improve lung function, exercise capacity, and HRQoL in ILD patients, particularly without high requirements for intervention duration. The efficacy of breathing exercises varies for different ILD subtypes, and incorporating breathing exercises as part of PR can be more beneficial for ILD patients. No studies have shown significant risks for ILD patients engaging in breathing exercises.