Ping Wu,1 Xin Qian,1 Yijing Hu,1 Xiaoxia Yan2 

1Department of Pulmonology, Shanghai Children’s Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, People’s Republic of China; 2Department of Thoracic Surgery, Shanghai Pulmonary Hospital, Shanghai, Tongji University, Shanghai, People’s Republic of China

Correspondence: Xiaoxia Yan, Department of Thoracic Surgery, Shanghai Pulmonary Hospital, Tongji University, 507 Zhengmin Road, Yangpu District, Shanghai, 200433, People’s Republic of China, Tel +86 13761286006, Email wup@shchildren.com.cn Yijing Hu, Department of Respiratory Medicine, Shanghai Children’s Hospital, Shanghai Jiao Tong University, 505 Tongpu Road, Putuo District, Shanghai, 200062, People’s Republic of China, Tel +86 18917180737, Email huyijing@shchildren.com.cn

Objective: The objective of this systematic review and meta-analysis was to assess the effectiveness of TIMT on pulmonary function in children and adolescents with asthma.
Method: We searched for randomized controlled clinical trials in the MEDLINE, Embase, the Cochrane Library, Web of Science, CINAHL, Sino Med, Wan fang, CNKI, and VIP until March 2024. In addition, the references included in the literature and the relevant systematic evaluation were manually traced in order to avoid the omission of any relevant literature. These trials compared TIMT against blank TIMT and conventional care. Eligible studies were assessed in terms of risk of bias and quality of evidence using RoB II tool. Where feasible, data were pooled and subjected to meta-analysis. The mean difference (MD) and 95% confidence interval (CI) were estimated by fixed effect models or random effect models.
Result: Six studies were included in the present meta-analysis involving 337 children and adolescents ranged from 4 to 18 years. The meta-analysis showed that TIMT could significantly improve lung function. Compared to the control group, TIMT can significantly improve FEV1 (MD 4.63 mL, 95% CI 2.64 to 6.62 mL, I2 = 4%), FVC (to the control group (MD 7.46 mL, 95% CI 5.09 to 9.82 mL, I2 = 0%), FEV1/FVC (MD 7.33%, 95% CI: 5.01 to 9.65%) and ACT (MD 1.86, 95% CI 0.96 to 2.75 mL, I2 = 12%) of patients at the end of intervention. There was no significant heterogeneity in these meta-analyses.
Conclusion: In conclusion, the results of this systematic review and meta-analysis support the effectiveness of TIMT training in restoring lung function and relieving asthma symptoms of asthmatic children. More high-quality and RCTs with large sample size are urgently required to verify the conclusion.

Keywords: threshold-pressure inspiratory muscle training, children, asthma, systematic review