Validation of skin surface microtopography as a measure of skin photoaging in a subtropical population aged 40 and over

Background: Evidence suggests that skin surface microtopography is a valid measure of photoaging among young adults, but whether this applies to older adults is unknown. Methods: We investigated the association between degree of photoaging as measured by histological dermal elastosis and skin microtopography grades by decade of age from 40 to 89 years in a community sample in Australia. Skin surface replicas and punch biopsies were taken from 664 participants of the Nambour Skin Cancer Study. The association was assessed using ordinal logistic regression with proportional odds assumption, using histological dermal elastosis grades as outcome. Results: There was significant increase in odds of higher skin surface microtopography grades with higher dermal elastosis grades for age groups below 70 years [40 to 49 years: odds ratio (OR) 2.96, 95% confidence interval (CI) 1.68-5.22; 50 to 59 years: OR 3.78, 95% CI 2.28-6.26; 60 to 69 years: OR 2.47, 95% CI 1.41-4.35). The association was not significant for those 70 years or older. Conclusion: Skin surface microtopography grading system is a valid measure of degree of dermal elastosis for middle-aged and older adults up to 69 years but appears not to be valid for adults 70 years or more living in a high sun exposure setting. © 2012 John Wiley & Sons A/S.