Current Measures of Healthspan in Aging

Progressive physiological decline in function occurs as age advances, which increases vulnerability to diseases and subsequently leads to disabilities in aging process. Modulation of genes and pathways has been reported to promote longevity in various animal model and its findings has been used in efforts to help maximize lifespan of human. Lifespan defines the number of survival days of an organism before death while healthspan is the period where an organism can function optimally and live free from diseases until the end of life. However, it remains unclear whether its benefit in prolonging lifespan also helps to improve healthspan since extended lifespan could also indicate a longer frailty period. The purpose of this review is to discuss healthspan assays used in various aging models. Healthspan analysis were found to be different depending on the advancement of biological functions. Domains of health commonly measured were accumulation of metabolites, physiological function and capacities. These measures generally declined with age. Interventions and treatments that promoted lifespan in different aging models improved the health measures although comparative analysis between treatment and control groups were limited to the normal lifespan of animals. Further determination of health measures focused on the extended period of life as a result of interventions and treatments in aging models would provide a better picture of their mechanistic action and validate the reported findings.