Phenotypes of atopic dermatitis and the risk for subsequent asthma: A systematic review and meta-analysis.

Abstract Background Various atopic dermatitis (AD) phenotypes showed an enormously heterogenic risk for subsequent asthma development. Objective We aimed to investigate the association between AD phenotypes and the risk for progression to asthma. Methods We searched PubMed, Embase, and Web of Science databases for relevant publications. Pooled relative risks (RR) with 95% confidence intervals (CI) were calculated using the CMA-3.0 software. This study has been registered with PROSPERO (CRD42019129273). Results We analyzed 39 publications with 458,810 participants. The RR for asthma in AD was 2.16 (95% CI, 1.88–2.48). The risk in persistent AD (RR, 3.36; 95% CI, 2.83–3.99) was higher than in transient AD (RR, 1.52; 95% CI, 1.34–1.73), and in severe AD (RR, 2.40; 95% CI, 1.96–2.94) was higher than mild (RR, 1.82; 95% CI, 1.03–3.23) or moderate (RR, 1.51; 95% CI, 1.30–1.75) AD. The risk for asthma in early-onset AD was slightly higher than in late-onset AD and in boys higher than girls. Limitations The AD and asthma definitions differed across the included studies. Conclusion Patients with persistent or severe AD were at a higher risk for developing asthma. These findings further elucidate the atopic march and identify target populations for asthma prevention.