Incidence and Prevalence of Psoriasis in Denmark.

The incidence and temporal trends of psoriasis in Denmark between 2003 and 2012 were examined. There was a female predominance ranging between 50.0% (2007) and 55.4% (2009), and the mean age at time of diagnosis was 47.7-58.7 years. A total of 126,055 patients with psoriasis (prevalence 2.2%) were identified. Incidence rates of psoriasis (per 100,000 person years) ranged from 107.5 in 2005 to a peak incidence of 199.5 in 2010. Incidence rates were higher for women, and patients aged 60-69 years, respectively. Use of systemic non-biologic agents, i.e. methotrexate, cyclosporine, retinoids, or psoralen plus ultraviolet A (PUVA) increased over the study course, and were used in 15.0% of all patients. Biologic agents (efalizumab, etanercept, infliximab, adalimumab, or ustekinumab) were utilized in 2.7% of patients. On a national level, incidence of psoriasis fluctuated during the 10-year study course. The relationship between psoriasis incidence and age appeared to be relatively linear, and disease prevalence was comparable to that in other European countries.