Age-Related Features of Instrumental Facial and Neck Skin Parameters: Associations With Blood Laboratory Parameters and Gut Microbiota

Background. Chronological age does not always reflect the severity of functional and morphometric skin changes. Integrated data on age-associated variability in quantitative facial and neck skin parameters and their associations with blood laboratory parameters and gut microbiota features remain limited. Aim. To assess age-associated functional and 3D morphometric characteristics of facial and neck skin and their associations with blood laboratory parameters and gut microbiota features in adult participants of the Russ-Age study. Methods. This single-center cross-sectional observational study included 183 outpatients aged 18-97 years. Skin hydration, elasticity, sebum, pigmentation, erythema and 3D skin parameters of the face and neck were assessed. The laboratory panel included markers of lipid and glucose metabolism, liver and kidney function, thyroid status, vitamin D status, inflammation, and hematological parameters. Gut microbiota analysis included taxonomic characteristics, alpha-diversity indices, and predicted functional pathways. Kruskal-Wallis test and Spearman correlation analysis were applied. Results. The sample comprised 141 women and 42 men. Age-associated differences were observed for skin elasticity, sebum, and all assessed 3D morphometric parameters. Age-stratified nominal correlations were identified between skin parameters, blood laboratory variables, and gut microbiota characteristics. In younger participants, associations primarily involved inflammatory, immunohematological, and selected biochemical variables, in middle-aged participants, glucose metabolism, vitamin D status, and hematological indices, in older participants, cellular blood characteristics, thyroid status, and liver-function parameters. Conclusion. Quantitative instrumental assessment captures age-associated variability in functional and 3D morphometric skin characteristics. Laboratory and microbiota associations differ across age groups and should be interpreted as exploratory associations.