P02 Skin ageing in South Asian individuals: biomechanical and functional mapping across the lifespan
Poonam Halai, Dafydd Thomas, Anya Shyne, Lindsay Cotterell, Anne Chandidzura, Clare O’Connor, Mike Bell, Mark Farrar, Abigail LangtonAbstract
Introduction and aims
As lifespans increase, maintaining skin healthspan – the period during which skin remains functional and resilient – is increasingly important. Skin ageing is influenced by intrinsic and extrinsic factors and varies across ancestral groups, yet South Asian (SA) individuals, one of the largest global populations, are under-represented in skin research. This study aimed to characterize how constitutive pigmentation affects skin structure, function and biomechanical ageing in SA individuals using integrated biophysical assessments.
Methods
A total of 109 healthy SA participants (39% male sex, 61% female sex; aged 18–90 years) were recruited across a wide pigmentation range quantified by individual typology angle (ITA). Skin elasticity was assessed using cutometry (4 mm probe, F3 parameter) at both photoprotected buttock and photoexposed forearm sites. Additional biophysical measurements were conducted, including transepidermal water loss (TEWL), stratum corneum hydration, and surface pH, while sebum levels were measured on the forehead. Multiple linear regression evaluated associations between age, sex and ITA.
Results
Constitutive pigmentation varied with age and sex: ITA increased with age indicating loss of pigmentation (P < 0.001), and men had darker skin than women (P < 0.001). Elasticity declined progressively with age at both photoprotected and photoexposed sites (P < 0.001), with men showing greater deterioration at sun-exposed sites. Lighter skin was associated with more pronounced age-related elasticity loss (P = 0.03). Sebum production decreased with age (P < 0.001), TEWL declined at both sites (P = 0.01), while hydration and pH remained largely stable. These findings demonstrate combined effects of intrinsic ageing and cumulative ultraviolet (UV) exposure, with pigmentation modulating the extent of functional decline.
Conclusions
SA skin ageing is associated with decreased pigmentation, reduced elasticity, and declines in sebum and barrier function. Thus, pigmentation may modulate vulnerability to photoageing and cumulative UV impact. Patterns are broadly similar to Northern European skin, suggesting common biomechanical ageing trajectories. Findings highlight the importance of photoprotection to prolong skin healthspan in SA skin.