P03 Intrinsic ageing in Far East Asian skin is accompanied by remodelling of the dermoepidermal junction without notable epidermal thinning

Introduction and aims Ageing is characterized by a progressive decline in physiological function and is influenced by both intrinsic and extrinsic factors. However, current understanding of skin ageing is based mainly on studies of White populations. Previous research has demonstrated that the structural organization of healthy skin is ethnicity-dependent, with alterations in epidermal morphology in White individuals linked to a decline in skin’s biomechanical properties. In this study, we employed quantitative epidermal morphometry to investigate whether parameters associated with intrinsic skin ageing in White individuals are similarly observed in Far East Asian populations. Methods Skin samples (n = 67; 3–86 years) were obtained from the Asian Skin Biobank from across the region and stained with haematoxylin and eosin for histological analysis, including assessment of dermoepidermal junction (DEJ) convolution and quantification of epidermal thickness. Weigert’s resorcin-fuchsin staining confirmed that all samples were photoprotected, with no histological evidence of solar elastosis. Results Comparative analysis revealed that geographical ancestry was invariant across Far East Asian populations in terms of epidermal morphology in young (< 20 years) individuals. However, flattening of the DEJ was observed with increasing age, which became significant in older individuals (> 50 years; P < 0.05). Notably, no significant age-related differences in epidermal thickness were detected across the age ranges. While intrinsic ageing in Asian skin is characterized by DEJ flattening – similarly observed in White populations – epidermal thickness remained unchanged. This contrasts with intrinsically aged skin of White individuals, where epidermal atrophy is a well-documented feature. Conclusions These findings suggest that the trajectory of intrinsic cutaneous ageing is likely ethnicity-dependent, emphasizing the need for diverse ethnic populations in cutaneous ageing research.