The effect of probiotics in the prevention of atopic dermatitis in children: a systematic review and meta-analysis

Background: Probiotics have anti-inflammatory effects and can alleviate clinical symptoms of atopic dermatitis (AD) in children. However, the effects of probiotics on AD in children were controversial. This study aimed to evaluate the clinical efficacy of probiotics in the prevention of AD in children by a meta-analysis method. Methods: Randomized controlled trials (RCTs) on probiotics in the prevention of AD in children performed at home and abroad were searched in the PubMed, Web of Science, China National Knowledge Infrastructure (CNKI), and Wanfang databases using a combination of subject terms and free terms. The retrieval time was from the establishment of the database to November 2022. Meta-analysis was performed by using Stata 14.0 software. The inclusion criteria were based on the Population, Intervention, Comparison, Outcomes and Study (PICOS) framework. (I) Participants: age <= 18; (II) Intervention: the intervention group received probiotics; (III) Control: the control group received placebo; (IV) Outcomes: AD; (V) the type of study: randomized control group. We collected the number of two groups and the number of AD in the included literatures. The I-2 statistic was employed to evaluate heterogeneity. Results: Thirty-seven RCTs were eventually included, including 2,986 in the experimental group and 3,145 in the control group. The meta-analysis showed that probiotics were superior to placebo in the prevention of AD [risk ratio (RR) (95% confidence interval): 0.83 (0.73, 0.94), I-2=65.2%]. The sub-group meta-analysis showed that the clinical efficacy of probiotics in the prevention of AD was more significant in the following groups: mothers and infants, before and after childbirth, Lactobacillus rhamnosus or mixed probiotics, follow-up time <= 2 years, and conducted in Europe. Conclusions: Probiotic intervention may provide an effective means of preventing AD in children. However, due to the heterogeneity of the results of this study, the results need confirmation in follow-up studies.