Sarcopenia in the elderly: diagnosis, physiopathology and treatment.

Sarcopenia, defined as a syndrome rather than as a pathology, is the loss of muscle mass and function associated with age. Sarcopenia is an enigma for medicine, and despite the numerous publications available in the literature and the number of papers currently being published, there is no agreement about its definition, and even less about its root causes. One salient aspect that proves the lack of consensus is the fact that different working groups are still debating about the right name for this syndrome (which is associated with the loss of muscle mass and strength in the elderly). In hospitalized patients, sarcopenia has been shown to raise the risk of complications such as infections, pressure ulcers, loss of autonomy, institutionalization and poor quality of life, as well as to increase mortality. The factors that contribute to the development of sarcopenia in the elderly are: the state of chronic inflammation, atrophy of motoneurons, reduced protein intake (secondary among others to the condition defined as geriatric anorexia), and immobility. There is ongoing debate about the causes of sarcopenia, but the aspect that generates most interest today is the quest to achieve repeatable and clinically useful diagnostic criteria for its diagnosis, prevention and treatment. The aim of this narrative review is to summarise the abundant information available in the literature and to draw useful conclusions.