On November 15, 2022, the total world population exceed the 8 billion milestones of with a steadily increase in life expectancy and aging [United Nations, 2020]. Parallel to aging, frailty is becoming a crucial topic because of its close association with older age.
Frailty is a multi-dimensional syndrome characterized by a decline in reserve and resistance to stressors across multiple physiological systems, strictly related to adverse outcomes: falls, fractures, difficulties in daily living activities, disabilities, hospitalizations and mortality. Two approaches are primarily adopted to define physical frailty: the deficit model that consists of adding together an individual’s number of impairments and conditions to create a Frailty Index and the other model that originally defined a specific physical phenotype investigating 5 possible components (weight loss, exhaustion, weakness, slowness, and reduced physical activity) .
A decline in muscle mass, function and strength, otherwise defined sarcopenia, increase the risk of incurring in health-related negative outcomes. Taking into account that sarcopenia is a clinical condition present in half of people over 80, it is evident that there is a remarkable overlap with frailty so as to be defined physical frailty and sarcopenia .
Being frailty a dynamic condition, it is possible to hypothesize socio-#economic or drug preventative interventions to tackle age-associate frailty and promote resilience.
In this scenario, the discovery of innovative biomarkers can be useful to orientate the interventions design and find the better window-time of their efficacy.
Nevertheless, considering the concept developed from Junius-Walker at al. (2018), that frailty probably derived from a based complex systems integrating the interplay of biological and non-biological factors , it is crucial to consider if some biological events are pure aging-associated changes, independent from other life events or are specific frailty determinants.
A key point in the identification of potential #biomarkers of frailty is the discovery of the hallmarks of #aging.
Among these, mitochondrial dysfunctions are central in the regulation of the aging process. Age-related impairment in mitochondrial function has been largely investigated assuming it may underlie multiple biological changes (decreased ATP production and energy reserves, increased free radicals production, altered rates of apoptosis and mitophagy) that increase vulnerability, functional and #cognitive decline and also mortality .
Davin A, Ferrari RR, Pansarasa O. Mitochondria: between aging, frailty and sarcopenia. Aging (Albany NY). 2023 Aug 22; 15:7863-7865 . https://doi.org/10.18632/aging.204998