Advanced glycated end products in skin as a potential biomarker for frailty

Abstract

Frailty is a multifaceted condition associated with increased vulnerability and heightened risk of adverse health outcomes. Recent studies have shown a possible association between the age related accumulation of advanced glycated end products (AGEs) and the development of frailty in the elderly. AGEs are associated with the onset of several (chronic) diseases through the induction of inflammatory responses, oxidative stress, and altered cell signalling. The accumulation of AGEs can be measured in skin using autofluorescence spectroscopy. With this review we show that AGE levels in skin show a positive correlation with several physical frailty components, especially low hand grip strength, declining muscle mass, and exhaustion. The association of AGE levels with commonly used frailty measures, namely Fried’s criteria and the Frailty Index, was present in some, but not all, included studies. Similar results were found for prediction of frailty by assessing AGE levels. There were only few studies investigating the relationship between cognitive frailty and AGE levels, but they show a strong confounding effect of cardiovascular disease. So far, determining AGE levels in skin shows promise as a non-invasive marker of physical frailty, but for especially for investigating prospective frailty and cognitive frailty, AGE levels should first be measured in larger, and especially longitudinal, cohorts.