3.5.3 PAQLQ
6 studies [15-17,26,27,34] provided PAQLQ data for meta-analysis, four comparisons with the control group (fig. 8a). The four parts of the PAQLQ: activity scores, symptoms scores, emotional scores, and total scores were analyzed. Compared with conventional treatment, both endurance training and interval training improved PAQLQ. Endurance training was in the activity scores [MD=1.32, 95% CI (0.60,2.03)], symptoms scores [MD=1.15, 95% CI (0.78,1.52)], emotional scores [MD=1.25, 95% CI (0.39,2.12)], total scores [MD=1.16,95% CI (0.66,1.66)]. Interval training was in the activity scores [MD=3.02, 95% CI (1.74, 4.30)], symptoms scores [MD=2.68, 95% CI (2.04, 3.32)], emotional scores [MD=2.47, 95% CI (0.91 ,4.03)], total scores [MD=2.68, 95% CI (1.79,3.57)] (fig. 8b-e). The ranking probability of the SUCRA ranking chart from high to low, activities scores: endurance training + resistance training + respiratory training, interval training, endurance training, respiratory training + strength training, conventional treatment (89.1%, 79.2%, 50.1%, 22.8%, 8.7%). Emotional scores: interval training, endurance training, respiratory training + strength training, conventional treatment, endurance training + resistance training + respiratory training (96.9%, 72.8%, 31.7%, 24.9%, 23.8%). Symptoms scores: interval training, endurance training, respiratory training + strength training, endurance training + resistance training + respiratory training, conventional treatment (100%, 74.5%, 30.9%, 29.7%, 14.9%). Total scores: interval training, endurance training, endurance training + resistance training + respiratory training, respiratory training + strength training, conventional treatment (99.9%, 71.7%, 36.9%, 26.5%, 14.9%). Comprehensive analysis of PAQLQ interval training superior to endurance training(8i-m).
Discussion
As a comprehensive intervention measure, PR has good advantages in relieving patients’ clinical symptoms, increasing exercise endurance and improving quality of life. It is considered as the first-line non drug therapy for chronic respiratory diseases, and widely used in the clinical practice of childhood asthma [38,39]. Exercise training, the cornerstone of PR, comes in a variety of forms, and it is unclear which form will have the best effect on childhood asthma. This systematic review provides a comprehensive overview of the design of PR-based programs implemented during asthmatic children and explores which types of exercise are most effective.
Our systematic review was based on 24 RCTs involving 1031 patients with asthmatic children. The Standard meta-analysis was based on 16 RCTs with 691 patients, and network meta-analysis was based on 13 RCTs with 433 patients. Most studies were conducted in an inpatient setting (29%) and the total duration of the intervention ranging from 4-52 weeks. Endurance training was the most used components, and most of the interventions included in the studies were combined with endurance training. 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. Exercise-based PR is a safe and effective for asthmatic children. Moreover, exercise-based PR is safe for asthmatic children, and no serious adverse events have been found.
Lung function, as an important adjustment index for the evaluation, treatment, and severity monitoring of bronchial asthma, has always been used for patient-level diagnosis and detection [40], and attracted more attention in the treatment of pediatric. The results showed that endurance training combine with respiratory training was significantly better than other forms of exercise in increasing FVC% pred and FEF25-75% pred, but no significant difference were found in FEV1% pred. This result may be due to the lack of exercise-based PR studies on childhood asthma and different degree of asthma, as well as the total duration of the intervention, the intensity and frequency of exercise training, etc.
It is reported that exercise can improve cardiorespiratory fitness, muscle strength, to relieve or control asthma [41]. Therefore, improving exercise capacity has a positive effect on children’s quality of life and asthma symptom control. 6MWT is an effective and reliable method for measuring children’s motor ability, which is safe, simple, and easy to operate [42]. Study results show that both endurance training and interval training improve 6MWT in childhood asthma, but interval training is better. These results support that exercise-based PR can improve exercise tolerance, which should be treated with caution because there are few studies included.
Symptoms and quality of life evaluation are important aspects of asthma control in children. The Children’s Asthma Quality of Life Questionnaire (PAQLQ) has high reliability and can more accurately reflect the quality of life in children with asthma [43]. The higher the score, the higher the quality of life. Six studies were included in the meta-analysis, exercise-based PR had a positive effect on the PAQLQ activity domain, emotional domain, symptom domain and total score. It is worth noting that interval training and endurance training are better than other forms of exercise, and interval training is the best. The results show that exercise-based PR can improve the PAQLQ score and improve the quality of life on childhood asthma.
Methodological considerations
What needs to be affirmed is that this systematic review and meta-analysis has certain advantages and limitations. So far, this is the only Network meta-analysis evaluate the effect of exercise-based PR on childhood asthma, and exercise-based PR includes a larger and richer literature. Network meta-analysis makes a direct and indirect comparison of various types of exercise interventions to determine the best type of exercise. At the same time, our study has some limitations. First, some studies have small sample size and poor representativeness, which may lead to inaccurate results. Second, some studies have not clearly stated the exercise intensity and frequency, which may lead to some differences in the results. In addition, it is very difficult to use exercise as an intervention and blind method, which may affect the authenticity of the results.
Conclusions
Exercise-based PR may be a safe and effective measure for childhood asthma to improve children’s lung function, exercise capacity, and quality of life. The combination of endurance and respiratory training seems to be the most effective for improvements on lung function. Interval training was more effective in improving quality of life and exercise capacity. Therefore, the effectiveness of exercise-based PR on childhood asthma control can provide a reference for children’s clinical treatment. However, the site, intensity, duration, and frequency of exercise interventions varied among included studies, so results may be controversial. In conclusion, it is necessary to validate large-scale, higher-quality RCTs in the future.
Authors’ Contributions
W Zhang and D Zhang were responsible for conception and design; J Jiang and ZG Wu were responsible for research screening; J Jiang and D Zhang were responsible for collection and assembly of data; J Jiang and YP Huang were responsible for study quality assessment; W Zhang and D Zhang were responsible for data analysis and interpretation; all authors were responsible for manuscript writing and final approval of manuscript. J Jiang and D Zhang contributed equally to this work and should be cofirst authors.