Aging and sarcopenia.

Sarcopenia is the loss of skeletal muscle mass resulting in a reduction of physical strength and ability to perform activities of daily living. Loss of muscle and strength with aging results in leading to an elevated risk of suffering a fall, difficulty recovering from illness, prolongation of hospitalizations, and long-term disability requiring assistance in daily living. Further, the reduction of muscle mass and physical strength leads to diminished quality of life, loss of independence, and mortality 1 . This loss of independence represents a high economic healthcare burden and area of high medical need. Sarcopenia also results when rapid muscle loss and reduced physical strength occurs due to disease-induced cachexia, immobilization, or drug-induced sarcopenia. The Institute of Medicine, a division of the National Academy of Sciences declared frailty associated with old age a priority area for national healthcare and an area that required increased research to deal with this healthcare issue 2 . Today, there are ~34M persons aged 65 and over – almost 13 percent of all Americans – and this number will grow to ~70M by 2030, representing 20% of the population 3 . Worldwide, the individuals who will become the frail elderly will more than double from ~321M in 1990 to ~799M in 2025. As a consequence of the expansion of this population segment along with increased longevity, the number of the elderly who will become sarcopenic and frail and require long-term institutionalization will consume an ever-expanding share of healthcare funds. In the US, 1.5M persons aged 65+ years are institutionalized each year, and 33% of these individuals are put into long-term healthcare facilities solely due to their physical and their inability to maintain prerequisite activities of daily living, with most frail elderly