[Sarcopenia: toward its clinical utilisation].
Sarcopenia is a term that was introduced to describe 'low muscle mass'. There is no consensus definition for sarcopenia; a variety of criteria are being used to establish the diagnosis of 'sarcopenia'. Depending on the criteria used, the prevalence of sarcopenia in elderly varies from 7% to over 50%. The presence of sarcopenia often remains unrecognized when the loss of muscle mass is replaced by fat and connective tissue; body weight thus remains stable or even increases. Sarcopenia can be detected by measuring muscle mass with dual-energy X-ray absorptiometry (DEXA) or bioimpedance analysis (BIA). Besides the generation of strength, muscle tissue is an important internal organ involved in protein storage, glucose regulation, hormonal homeostasis and cellular communication. Systemic, cellular, neuromechanical factors and lifestyle are linked to the pathophysiology of sarcopenia. Sarcopenia is associated with higher mortality, dependency in activities of daily living, toxicity of chemotherapy, and disturbed glucose regulation.