Sarcopenia: Its definition, prevalence, functional outcomes and prevention

抄録

Aging is associated with progressive loss of muscle mass and strength, which may lead to a geriatric syndrome known as sarcopenia. Sarcopenia was originally defined as loss of muscle mass, however, recent definitions have incorporated other components such as muscle strength and physical performance. Regardless of definition, low muscle mass is a key factor in sarcopenia. Sarcopenia is substantially prevalent among older adults, and is associated with poor functioning. It also predicts adverse health outcomes such as falls, frailty, disability and mortality. Sarcopenia is a multifactorial syndrome; its etiology is complex, and contributing factors interact with each other. However, there are two major modifiable factors that we should target in order to prevent and treat sarcopenia - physical activity and nutrition. Life-course approach may be important, however, it is not too late to benefit from interventions in later life. Appropriate physical activity including resistance exercise and optimal nutrition including adequate protein intake are important in the primary prevention of the sarcopenia process. In order to improve the physical condition of those currently experiencing a sarcopenic state, effective programs are now being developed, some of which use progressive resistance training in combination with specific nutrient supplementations. Life styles and body composition are quite different in Western and Asian countries. There is an urgent need to establish a consensus on the definition of sarcopenia for those of Asian descent. It would be of great help for health professionals as well as clinicians in this area.