Driving Time and Facial Skin Hydration Asymmetry in Florida Drivers (DCHA-FL-25-65)

his observational study examines whether time spent driving is associated with differences in skin hydration between the left and right cheeks in female drivers residing in Florida. In left-hand-drive vehicles, the driver's left cheek is chronically exposed to ultraviolet A (UVA) radiation through the unshaded side window during every daytime driving episode. A prior study by IAS Skin Care (NCT07564869, n=30) found that the left cheek was less hydrated than the right cheek in 60% of participants, suggesting a possible effect of driving-related UVA exposure on facial skin hydration asymmetry.

Eighty female drivers aged 25-65 years residing in Florida will be enrolled. At a single visit, skin hydration will be measured at three facial zones (left cheek, right cheek, and forehead as a symmetrical control zone) using the BT-Analyze bioimpedance device. Participants will complete a structured questionnaire on driving habits, sun protection practices, and skin history. The primary outcome is the Hydration Asymmetry Index (HAI = right cheek minus left cheek BT-Analyze score). Associations between driving time, cumulative driving exposure, window tinting, sunscreen use, and HAI will be examined using Spearman correlation, Mann-Whitney U tests, and multiple linear regression.