Effects of exercise-based pulmonary rehabilitation on children with asthma：a systematic review and network meta-analysis

Objective: This systematic review aimed to systematize different designs of exercise-based pulmonary rehabilitation (PR) for children with asthma and explore which designs are optimal. Methods: PubMed, EMBASE, Cochrane Library, Web of Science Core Collection and MEDLINE were searched up until April 01, 2021, which was conducted for any relevant randomized controlled trials (RCTs) of exercise-based PR in childhood asthma. Language is limited to English. Network meta-analyses and standard meta-analyses were performed using STATA (version 16.0), quality analyses were performed using RevMan (version 5.3). Results: A total of 24 RCTs involving 1031 patients were included. 14 studies were endurance training, which was the most commonly used form of exercise, and 7 studies rehabilitation sites were conducted in hospitals. A network meta-analysis showed that compared with other forms of exercise, interval training significantly improved the PAQLQ (Pediatric Asthma Quality of Life Questionnaire), including activity scores [MD=3.02, 95% CI (1.74,4.30)], symptom scores [MD=2.68, 95% CI (2.04,3.32)], emotional scores [MD=2.47, 95% CI (0.91,4.03)], and total scores [MD=2.68, 95% CI (1.79,3.57)]. Interval training [MD=188.97, 95% CI (-59.27, 437.21)] also had a more significant effect on the 6MWT (6-minute walk test). No adverse events were found in this study. Exercise training had no significant effect on FEV (the forced expiratory volume at 1s to predicted value ratio) [WMD=0.59, 95% CI (-2.00, 3.19)], however, the combined of endurance training and respiratory training was found to significantly improve both FVC (the forced vital capacity to predicted value ratio) [MD=5.37, 95% CI (0.07,10.67)] and FEF25-75% (the forced expiratory flow between 25% and 75% of vital capacity ratio) [WMD=11.31, 95% CI (2.13, 20.48)]. Conclusions : Exercise-based PR is a safe and effective for childhood asthma. Interval training may be a core component of improving quality of life and exercise capacity in childhood asthma, the combination of respiratory training and endurance training has significant effects on lung function.This result should be viewed with caution, and high-quality RCTs are still needed to confirm its clinical efficacy,