The age-of-onset of psoriasis and the relationship to parental psoriasis

In series of 419 consecutive patients with psoriasis the peak age-of-onset was between 5 and 9 years of age in girls and between 15 and 20 years in boys. Subsequently, there was a gradual decline in relation to age. The incidence of psoriasis in a parent of a proband was shown to be significantly higher in those patients where a detailed exmination of the family was undertaken, as compared with the information obtained only from case records.