Background Inhaled short-acting β2-agonists (SABA) is recognised as an effective treatment in adults and older children with asthma, but the effect in young children and infants is still up for debate. We examine the efficacy of inhaled SABA for preschool-aged children presenting with acute wheeze/asthma in this systematic review and meta-analysis.

Methods PubMed and Embase were searched through August 2024. Clinical trials investigating the effect of inhaled SABA on acute wheeze/asthma symptoms in children below age 6 years were included. The study followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Summary standardised mean differences, 95% CIs and p values were derived from random effects meta-analyses to analyse the effect on clinical composite respiratory score, respiratory rate, oxygen saturation, respiratory work and degree of wheezing.

Results A total of 19 studies including 1022 children were included. Treatment with inhaled SABA showed decreased respiratory score within 60 min (10 studies, N=523): standardised mean difference −2.05 points (95% CI −2.50; −1.59), I²=86%, p<0.001, decreased respiratory rate (8 studies, N=319): −0.86 (95% CI −1.30; −0.41), I²=87%, p<0.001, increased oxygen saturation (7 studies, N=190): 0.56 (95% CI 0.16; 0.95), I²=71%, p<0.01, decreased respiratory work (3 studies, N=68): −0.80 (95% CI −1.60; −0.00), I²=74%, p=0.05 and decreased wheezing score (3 studies, N=68): −1.07 (95% CI −1.80; −0.33), I²=72%, p<0.01. Subgroup analyses of children below age 2 years showed similar significant effects for all outcomes.

Conclusions Inhaled SABA treatment for acute wheeze/asthma symptoms showed beneficial effects in young children and infants. Findings from this study may provide evidence to support inhaled SABA in future treatment guidelines for acute wheeze/asthma among young children and infants; however, an overall high heterogeneity and small sample size of the studies were a limitation.

PROSPERO registration number CRD42023429381.