Rhinitis prevalence and association with atopic dermatitis: A systematic review and meta-analysis.

BACKGROUND: Atopic dermatitis (AD) and rhinitis are common atopic diseases that may co-occur owing to an overlap in pathophysiology. Although most cases of both diseases are mild and managed with topical anti-inflammatory medicaments, the advent of new systemic and biologic treatments targeting type 2 inflammation in both diseases warrants further insight in the exact overlap of AD and rhinitis. OBJECTIVE: To determine the association between AD and rhinitis. METHODS: A systematic review and meta-analysis of the databases PubMed, Embase, and CNKI were performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Pooled prevalence and pooled odds ratios (ORs) with 95% confidence intervals (95% CIs) were calculated. RESULTS: The search resulted in 10,422 citations, and 341 and 302 articles were included in the qualitative and quantitative analyses, respectively. The pooled prevalence of rhinitis was 40.5% (95% CI 39.0-42.0) in patients with AD and 18.0% (95% CI 16.7-19.2) in the reference individuals without AD. The pooled prevalence of having both rhinitis and asthma was 14.2% (95% CI 13.0-15.5) in patients with AD. There was an association between AD and rhinitis (OR 3.00, 95% CI 2.83-3.18), allergic rhinitis (OR 3.25, 95% CI 2.26-4.66), and nonallergic rhinitis (OR 1.99, 95% CI 1.39-2.86), respectively. CONCLUSION: Rhinitis, both allergic and nonallergic forms, is very common in patients with AD. Future investigations should clarify how medications targeting both diseases should be indicated in these patients.

Prevalence of asthma in patients with atopic dermatitis: A systematic review and meta-analysis.

BACKGROUND: It is well established that asthma is common in patients with atopic dermatitis (AD). OBJECTIVES: We performed a systematic review and meta-analysis to determine the prevalence of asthma and respiratory symptoms in individuals with AD as well as the association between AD and asthma. METHODS: At least 2 authors independently searched the medical databases PubMed, EMBASE, LILACS, and SCOPUS for all English-language studies with data on asthma prevalence among patients with AD or the association between AD and asthma. Pooled odds ratios with 95% confidence intervals (CIs) and pooled proportions were estimated with random-effects models. The Newcastle-Ottawa scale was used to assess study quality. RESULTS: The search yielded 39,503 articles. Of these, 213 studies were included in a quantitative analysis. The overall pooled prevalence of asthma was 25.7% (95% CI, 23.7-27.7) in patients with AD and 8.1% (95% CI, 7.0-9.4) among reference individuals. There was a significant association between AD and asthma when compared with reference individuals (odds ratio, 3.03; 95% CI, 2.64-3.47). LIMITATIONS: The definitions of AD and asthma differed across the included studies and varied from self-report to physician diagnosed. CONCLUSIONS: Asthma is a common comorbidity of AD. Physicians should be cognizant of this relationship and address asthma symptoms in their patients.