Papulosquamous disease

Extract Essentials Psoriasis Psoriasis is one of the most common and easily identifiable inflammatory skin diseases. In Western Europe the prevalence of psoriasis is estimated at 2%, but is higher in parts of Scandinavia, e.g. the Faroe Islands, where it reaches 5%. Worldwide, the disease is rare in Inuit, native American, Japanese, and Afro–Caribbean people, and has been estimated to affect just 0.3% of the general population in China. There is no evidence that the incidence of the disease is changing, by contrast with the year-on-year increase in atopic dermatitis. Overall, the sex incidence is equal, and the mean age of onset is 33 years, but 75% of cases occur before the age of 40 years. Disease starts earlier in females than males, indicating hormonal influences. Late-onset disease (type II), occurring after the age of 40 years, reaches a peak at onset between the ages of 55 and 65 years. There appears to be no association with either social class or diet.