Prevalence and incidence of psoriasis and psoriatic arthritis

Psoriasis (Pso) and psoriatic arthritis (PsA) are inflammatory disorders which can severely impair health and quality of life. For both Pso and PsA, an increasing prevalence has been reported.1 2 Comprehensive data on the prevalence and incidence of Pso and PsA are important in order to adequately allocate specialist care and financial resources. These data are incomplete for Pso and especially PsA. In particular, no population-based study has estimated their prevalence or incidence in Germany. We obtained the statutory health insurance data of approximately 65 million people from 2009 to 2012, covering 80% of the German population. Pso and PsA age-standardised prevalence based on the International Classification of Diseases (ICD) codes was obtained and age-standardised incidence rates calculated as described previously.3 Briefly, cross-sectional prevalence data of consecutive years were used in conjunction with different assumed mortality rates of 1.1–1.5, with assumed …