Psoriatic arthritis is a strong predictor of sleep interference in patients with psoriasis.

Objective We sought to determine what clinical features of psoriasis predict sleep interference. Methods Data were obtained from 420 respondents to the 2005 National Psoriasis Foundation telephone and e-mail surveys. Logistic regression was used to determine whether disease severity, body mass index, age of onset, psoriatic arthritis, income, ethnicity, sex, current therapy, and quality-of-life measures predicted reported sleep interference within the last month. Results Psoriatic arthritis was the most significant predictor of sleep disturbance (odds ratio=3.26). Itch, pain of lesions, and impact on emotional well-being were also significant predictors (odds ratio 1.26, 1.22, and 1.18, respectively). Body surface area covered with psoriasis, body mass index, and therapy were not significant predictors of sleep interference. Limitations All data were self-reported and not physician-assessed. Conclusions History of psoriatic arthritis, presence of itch and pain of psoriatic lesions, and impact of psoriasis on overall emotional well-being predict sleep interference.