Association of atopic dermatitis with smoking: A systematic review and meta-analysis

Tobacco exposure might be a modifiable risk factor for atopic dermatitis (AD).

We examine the association between AD and exposure to tobacco smoke.

We performed a systematic review and meta-analysis of observational studies (n = 86) in MEDLINE, EMBASE, Scopus, and Cochrane Library (1823-2015). Quality of evidence was assessed using the Newcastle-Ottawa Scale (NOS). A meta-analysis was performed using random-effects models to estimate pooled odds ratios (OR). Subset analyses were performed for different ages (children, adult), regions, study designs (cross-sectional, longitudinal), study sizes (<5000, ≥5000), study quality (NOS score <6, ≥6), and amount of smoking (mild, extensive).

A diagnosis of AD was associated with higher odds of active smoking (OR 1.87, 95% confidence interval 1.32-2.63) and exposure to passive smoke (OR 1.18, 95% confidence interval 1.01-1.38), but not maternal smoking during pregnancy (OR 1.06, 95% confidence interval 0.80-1.40). The association between active smoking and AD remained significant in children and adults, all continents studied, and study sizes, but all were cross-sectional designs and had NOS score 6 or greater. Passive smoke was associated with AD in children and adults, cross-sectional studies, South/Central American and African studies, study size less than 5000, and NOS score less than 6.

AD severity and distribution were not assessed.

Active and passive exposure to smoke are associated with increased AD prevalence.