Assessment of sarcopenia

Abstract

Sarcopenia is defined as the loss of muscle mass that occurs during normal aging and is associated with functional impairment. This is a dynamic concept that should consider the reduction of muscle mass over time but, for practical purposes, we must rely on cross-sectional measures to determine the presence of a significant loss of muscle mass. Double energy X ray absorptiometry is a reasonably accurate and inexpensive method to determine body composition. Knowing the body composition of a representative sample of older subjects in a specific community, regression equations to predict muscle mass can be derived to determine which individuals are sarcopenic using the residuals method. Functional measures should also be incorporated in the assessment of sarcopenia. The most popular assessments include walking capacity, the ability to rise from a chair and the measurement of muscle strength using dynamometers. A lower muscle mass and function in older subjects are risk factors for mortality and disability. Physical training is the only intervention capable of reverting the adverse consequences of sarcopenia.