The cause of frailty and loss of resilience is probably a progressive loss of redundancy in these response patterns and connections.
Sarcopenia, the leading cause of frailty and disability in the elderly, has also been linked to other age-associated pathology, such as osteoporosis and impaired thermoregulation [ 2- 5].
5– 7 It is a major cause of frailty 6 and, importantly, predicts future mortality in middle-aged as well as older adults.
The complexity of old age health makes it difficult to determine whether the loss of B-cell diversity is a cause of frailty, or is a consequence of a decline in health from other causes.
Age-related shift towards decreased muscle mass and increased (abdominal) fat mass is an important cause of frailty, loss of independence, and metabolic and cardiac disease, resulting in impaired quality of life 1 and increased mortality in the aged.
Among the many biological, physiological, social and psychosocial models on the possible causes and pathways of frailty [ 1, 11- 18], the one that has attracted considerable attention is the "phenotype of frailty" [ 1].
Moreover, diabetes in the elderly is a well-recognized cause of accelerated frailty, disability, hospitalization, institutionalization, and death, thus absorbing a growing fraction of healthcare resources [ 14, 27, 28].
Illness can cause temporary episodes of frailty.
Fatigue/low vitality is often a symptom of underlying psychiatric or medical illness and is increasingly seen as an early indicator of frailty, caused by increased vulnerability in multiple biologic and physiologic systems [ 5].
25 Atherosclerotic processes can prevent blood flow through the coronary artery, causing CVD, 25 and through the muscles, causing sarcopenia, a clinical feature of frailty.
