title: Assessing the impacts of lifetime sun exposure on skin damage and skin aging using a non-invasive method.
abstract: BACKGROUND
  Ultraviolet radiation exposure during an individuals' lifetime is a known risk factor for the development of skin cancer. However, less evidence is available on assessing the relationship between lifetime sun exposure and skin damage and skin aging.
  
  
  OBJECTIVE
  This study aims to assess the relationship between lifetime sun exposure and skin damage and skin aging using a non-invasive measure of exposure.
  
  
  METHODS
  We recruited 180 participants (73 males, 107 females) aged 18-83 years. Digital imaging of skin hyperpigmentation (skin damage) and skin wrinkling (skin aging) on the facial region was measured. Lifetime sun exposure (presented as hours) was calculated from the participants' age multiplied by the estimated annual time outdoors for each year of life. We analyzed the effects of lifetime sun exposure on skin damage and skin aging. We adjust for the influence of age, sex, occupation, history of skin cancer, eye color, hair color, and skin color.
  
  
  RESULTS
  There were non-linear relationships between lifetime sun exposure and skin damage and skin aging. Younger participant's skin is much more sensitive to sun exposure than those who were over 50 years of age. As such, there were negative interactions between lifetime sun exposure and age. Age had linear effects on skin damage and skin aging.
  
  
  CONCLUSIONS
  The data presented showed that self reported lifetime sun exposure was positively associated with skin damage and skin aging, in particular, the younger people. Future health promotion for sun exposure needs to pay attention to this group for skin cancer prevention messaging.
authors.affiliation: AusSun Research Lab, Institute of Health and Biomedical Innovation, Queensland University of Technology, Australia. m.kimlin@qut.edu.au
authors.forename: Michael G
authors.initials: MG
authors.lastname: Kimlin
authors.forename: Yuming
authors.initials: Y
authors.lastname: Guo
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001315:Australia; D005127:Eye Color; D005260:Female; D006200:Hair Color; D006801:Humans; D008297:Male; D008875:Middle Aged; D012867:Skin / Q000528:radiation effects*; D015595:Skin Aging / Q000528:radiation effects*; D012878:Skin Neoplasms / Q000209:etiology / Q000517:prevention & control; D013472:Sunlight / Q000009:adverse effects*; D055815:Young Adult