Histologic changes in skin associated with aging.

This is a review of histologic changes noted in the skin of elderly individuals. Among the epidermal changes associated with skin aging are a flattened dermal-epidermal junction, giving the appearance of atrophy and cellular heterogeneity. The melanocyte density declines slowly, and the Langerhans cells decrease in number with advancing age. Among the dermal changes are attenuation in the number and diameter of elastic fibers in the papillary dermis, an increase in number and thickness of the same fibers in the reticular dermis, and a coarsening of collagen fibers with an increase in density of the collagen network. A decrease in the dermal cell population as well as a functional decline in glandular activity are also noted with intrinsic aging. A decline in hair number, rate of growth, and diameter, along with a slowing of the rate of growth of nails, have been well documented with progressive aging.