Effect of smoking and sun on the aging skin.

Smoking and ultraviolet radiation are known to have a detrimental effect on human skin. Important characteristics of the aging skin are elastosis and telangiectasia. The purpose of the study was to assess the relative importance of age per se, and the detrimental effects caused by sun exposure and smoking on the development of cutaneous elastosis and telangiectasia in a well-defined group of individuals. We made use of 966 individuals who participated in a case-control study to investigate environmental and genetic risk factors for skin cancer. Exposure measurements for sunlight and smoking were collected and the amount of elastosis and telangiectasia in the face and neck was recorded according to a four-graded score varying from none to severe. Relative risks were estimated using exposure odds ratios from cross-tabulation and logistic regression. Multivariate logistic regression was used to adjust for potential confounders. Among both sexes a strong association was observed between increasing age, sun exposure, and amount of elastosis. The association between increasing age, sun exposure, and amount of telangiectasia was strong among men, but less apparent among women. Smoking was also associated with elastosis among both sexes, and with telangiectasia predominantly among men. Intrinsic differences between men and women (e.g., hormones) or behavior differences (e.g., more frequent use of creams and cosmetics among women) could account for this apparent difference in the occurrence of telangiectasia. In contrast to elastosis, telangiectasia may not be a good marker of the aging skin, specifically not in women.