The prevalence of seborrheic keratoses in people aged 15 to 30 years: is the term senile keratosis redundant?

BACKGROUND Seborrheic keratoses (SKs) are common skin lesions that have been shown to occur with increasing age, although the age of onset is not well recorded. OBJECTIVE To determine the prevalence, nature, and distribution of SKs in young people. METHODS One hundred seventy people aged 15 to 30 years were given a total body examination during which the presence, number, site, and size of SKs were recorded. Biopsy specimens were taken from the first 22 people who had lesions clinically diagnosed as SKs. Data on age, skin type, eye color, and hair color were recorded for all respondents. RESULTS Forty (23.5%) of 170 respondents had at least one SK, with no significant difference between the sexes. There was an increase in prevalence with age from 15.7% in 15- to 19-year-olds to 32.3% in those aged 25 to 30 years. The size of the SKs also increased with age. A total of 77.5% of SKs were found on the trunk and 22.5% on the limbs, head, and neck. There was no correlation between SKs and any particular hair and eye color or skin type. CONCLUSIONS These findings confirm that SKs are common lesions in young Australians, appearing in a substantial proportion of people younger than 30 years. The term senile keratosis is no longer appropriate for these lesions.