Incidence of atopic conditions in people with psoriasis: a population-based analysis

Large-scale data on the association between psoriasis and atopic diseases are scarce.

To evaluate the concomitant prevalence of atopic conditions and psoriasis.

In this cross-sectional study, employees between 16 and 70 years of age were examined in more than 400 German companies by dermatologists, between 2006 and 2014. Two different definitions of atopic conditions were applied: "current atopic condition" (point prevalence) and "current or previous atopic condition" (lifetime prevalence). Bivariate comparisons as well as logistic regression analyses controlling for age and sex were performed.

In total, 90,265 persons were included in the study; 58.5% male; mean age: 43.2 ± 10.7 years. Point prevalence for psoriasis was 2.0% (n = 1,788), and lifetime prevalence of atopic conditions was 32.7% (n = 29,501). Atopic conditions were significantly less frequent (29.6%, n = 530) in persons with psoriasis compared to those without psoriasis (32.7 %, n = 28,917; OR = 0.865; CI: 0.781 - 0.959). Concurrent and prior atopic conditions were observed in 13.7% (n = 245) of persons with psoriasis versus 15.6% without psoriasis (n = 13,835; OR = 0.857; CI: 0.748-0.981). Controlling for age and sex, significant differences were found between persons with and without psoriasis for symptomatic atopic conditions such as hypersensitivity to pollen (OR = 0.864; CI: 0.748-0.997) and animal epithelia (OR = 0.764; CI: 0.609-0.958).

Even though the prevalence of atopic diseases is less frequent in individuals with psoriasis than in those without psoriasis, this study suggests that atopic conditions such as atopic dermatitis may also play a relevant role in psoriasis.