Clinical impacts of sun exposures on the faces and hands of Japanese women of different ages

Abstract

To assess the impacts of sun exposures on some skin signs on the faces and hands of differently aged Japanese women, according to their distinct behaviours towards vis à vis sun exposure. Two comparable cohorts of Japanese women (aged 18-83years) were created according to their usual behaviour towards sun exposure i.e. non-sun-phobic (N=495) and sun-phobic (N=516) and through their regular use(s) of a photo-protective product. Standard photographs (full-face and 45° lateral) allowed to focus on 18 facial signs that were graded by 15 experts, using a referential skin ageing Atlas. From these two cohorts, two sub-cohorts (114 and 122 women) were created with regard to the similar clinical aspects of the dorsal side of their hands (Left vs. Right) that were further graded. Absolute differences in the scores of each sign were used (non-sun-phobic minus sun-phobic), by age-ranges, to better ascertain the impact of sun exposures and photo-protection. Facial signs related to skin wrinkles/texture and pigmentary spots were found significantly more accentuated among non-sun-phobic women and show an early onset (20-30years). Facial sagging and crow's feet wrinkles appear delayed (30-40years). The severity of vascular disorders was found to be similar in the two cohorts. The absolute differences in the grading's of almost all signs were unsurprisingly found increased with advancing ages, illustrating the combination of chronological and photo-ageing processes. With regard to hands, differences in skin texture and pigmentary disorders are of a late onset (40-50years) and were found much increased at older ages. The cutaneous signs of the hands of Japanese women can hardly be taken as reliable markers of their photo-ageing status. The present work illustrates, for the first time, some specificities of the impact of sun exposures on the facial skin of Japanese women, pinpointing the fact that some facial signs are of an early onset. Results significantly confirm the importance of both sun avoidance coupled with photo-protective measures.