A defined general population of 159,200 male and female native Swedes born in the period of 1911-1940, from an urban catchment area of the then only general hospital, was followed over a decade (1970-1979) with regard to inpatient hospitalization for all kinds of diagnoses. Psoriasis cases (n = 372) are significantly (p less than 0.001) associated with a spectrum of diseases: male as well as female psoriatics seem to show excess rates of viral infections, alcoholism, hypertension, pneumonia, liver cirrhosis, urticaria, and rheumatoid arthritis. Psoriasis in males only seem to be associated with iritis and ankylosing spondylitis, whereas psoriasis in females only is associated with lung cancer, diabetes, obesity, myocardial infarction and asthma.