Atopic dermatitis and tobacco smoke exposure during childhood and adolescence.

BACKGROUND: Tobacco smoke may affect atopic dermatitis (AD) because of its known effects on humoral and cellular immunity, but prior studies lack data on disease severity and biomarkers over time. OBJECTIVE: We investigated the association between passive and active tobacco smoke exposure (TSE) during childhood and adolescence and the activity and severity of AD. METHODS: A birth cohort of 10,521 individuals was followed through adolescence as part of the Avon Longitudinal Study of Parents and Children. We used mixed-effect models to determine the risk of AD (based on repeated assessments) with passive smoke exposure during childhood, active TSE during adolescence, and using a serum biomarker of tobacco exposure (cotinine) at 3 time points. RESULTS: After adjusting for confounding factors, there was no evidence of a relationship between passive TSE and concurrent AD activity in childhood (adjusted odds ratio, 0.95; 95% confidence interval, 0.83, 1.07) or of an increased risk between active smoking and AD activity in adolescence (adjusted odds ratio, 0.57; 95% confidence interval, 0.44, 0.75). Secondary analyses demonstrated no dose-response relationship and no increased severity of AD with passive or active TSE. Furthermore, we found no increased risk of AD with a cumulative measure of passive TSE across childhood (adjusted relative risk ratio, 0.98; 95% confidence interval, 0.96, 1.00). CONCLUSION: Neither active nor passive TSE was associated with AD during childhood and adolescence.