[Pathophysiological and biological mechanisms in frailty]

Frailty is a common clinical syndrome in older adults, characterised by reduced physiological reserve and impaired homeostasis across multiple organ systems. Frailty arises from cumulative biological changes rather than chronological ageing alone. Key mechanisms include cellular damage, mitochondrial dysfunction, chronic low-grade inflammation, sarcopenia, osteoporosis, and reduced neurological reserve. This review finds that these interacting processes lead to impaired stress responses, functional decline, increased fall risk, and vulnerability to adverse health outcomes.