Epidemiology of Sarcopenia

Sarcopenia is a term describing the age-related loss of muscle mass, muscle strength, and/or physical function. It is a progressive, and generalized disorder that is multifactorial in origin, and associated with a considerable burden of morbidity, in terms of falls and fractures, cognitive impairment, frailty, disability, and hospitalizations. The health economic burden of sarcopenia is considerable and looks set to continue to increase as the proportion of older persons in the population rises. In this chapter, we briefly describe some of the most commonly used existing definitions of sarcopenia and review the prevalence of sarcopenia in various settings (community-dwelling adults and hospitalized individuals). We review the modifiable and non-modifiable risk factors, which include age, gender, nutrition, exercise, smoking, or alcohol consumption. Finally, we review the burden of sarcopenia on healthcare costs in the hospital setting, from a societal perspective. Further high-quality research in the field of sarcopenia is warranted, using standardized operational definitions of sarcopenia, to identify factors that could be leveraged to prevent or slow the onset or progression of sarcopenia. Systematic screening of older individuals is also warranted to identify persons with decreasing muscle strength, who may be at risk of sarcopenia and its associated negative consequences.