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Frailty, fitness, and the mathematics of deficit accumulation

  • Kenneth Rockwood (a1) (a2) and Arnold Mitnitski (a2)


The daily clinical practice of geriatric medicine is a grapple with complexity. The elderly patients who come to geriatricians typically have multiple, interacting, age-related physiological impairments, some of which manifest as medical problems. These interact with various social vulnerability factors to put them at risk, and to define them as being frail. This view of frailty, as a multiple-determined state of vulnerability has broad support, but how best to operationalize frailty is rather more controversial. Some of the proposed operational definitions receive more widespread support than others. In particular, the ‘phenotypic’ definition of frailty used in the Cardiovascular Health Study (CHS) has been endorsed at consensus conferences and employed by several groups. Indeed, it has even been claimed that ‘the terms “frail” and “frailty” should be avoided except when used in the context of a CHS assessment.’


Corresponding author

Address for correspondence: Professor K Rockwood, Centre for Health Care of the Elderly, 1421–5955 Veterans' Memorial Lane, Halifax, Nova Scotia, Canada.


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