Process of physical disability among older adults--contribution of frailty in the super-aged society.

One of the critical issues that Japan, well known for the world's highest proportion of older adults, a super-aged society, is currently confronting is how to prevent physical disability in old age. This issue is particularly important not only from a medical perspective such as functional prognoses but also from a socio-economic angle in view of reducing the rapid rise in the cost of medical and long-term care insurance services. Functional decline in old age results not only from acute diseases but also from frailty. Such a common and important syndrome that is increasingly prevalent with advancing age can be the cause. The present article intends to review what is known about frailty, including its definition, epidemiology, and pathophysiology, and to examine potential areas of future research.