Association between atopic dermatitis and obesity in adulthood.

Background: Obesity in early childhood is associated with increased risk for and severity of atopic dermatitis (AD). Objective To determine whether obesity in adulthood is associated with risk of AD.

Methods: This was a retrospective case-control study of 2090 adults using questionnaire, height and weight, and skin-prick testing between January 1994 and December 2003.

Results: Obesity in adults was associated with increased AD [multinomial logistic regression: adjusted odds ratio (aOR) 1·43, 95% confidence interval (CI) 1·08-1·89; P=0·01], but not nonatopic dermatitis (aOR 0·59, 95% CI 0·21-1·68; P=0·32). Obesity was also associated with increased atopic asthma (aOR 1·98, 95% CI 1·47-2·66, P<0·0001), but not associated with nonatopic asthma (P=0·20), atopic or nonatopic rhinoconjunctivitis (P=0·08 and 0·31, respectively), food allergies (P=0·67 and 0·35, respectively) or atopy (P=0·40). The association between obesity and AD remained significant even when controlling for history of asthma, rhinoconjunctivitis and food allergies (aOR 1·40, 95% CI 1·05-1·86; P=0·02) or in subset analyses of subjects with AD alone (aOR 1·96, 95% CI 1·02-3·75; P=0·04) and with comorbid asthma, rhinoconjunctivitis and/or food allergies (aOR 1·40, 95% CI 1·03-1·91; P=0·03).

Conclusion: Obesity in adulthood is associated with AD. Further studies are warranted to determine if weight loss may prevent or mitigate AD in adults.