TY - JOUR
T1 - Going from bad to worse
T2 - A stochastic model of transitions in deficit accumulation, in relation to mortality
AU - Mitnitski, Arnold
AU - Bao, Le
AU - Rockwood, Kenneth
N1 - Funding Information:
These analyses were supported by the Canadian Institutes for Health Research (CIHR) operating grants MOP62823 and MOP64169, and by the Dalhousie Medical Research Foundation (DMRF). KR is supported by the CIHR through an investigator award and by the DMRF as Kathryn Allen Weldon Professor of Alzheimer Research. Each co-author asserts no proprietary interest in the result and no financial conflict of interest.
PY - 2006/5
Y1 - 2006/5
N2 - As people age, they accumulate deficits. The more deficits they accumulate, the greater their vulnerability, which can be expressed as the probability to accumulate even more deficits, or to die. The probability of death is known to be exponentially related to the number of deficits. Using data from elderly (aged 65+ years) participants in the Canadian Study of Health and Aging (n = 9008), we investigated the relationship between the number of deficits and the change in the number of deficits over two successive 5 year intervals. We show that the probabilities of changes in the number of deficits, in relation to baseline, are well fitted (R2 > 0.98) by a simple distribution, with two parameters. The model suggests a maximum to deficit accumulation, and illustrates no level of deficit accumulation at which there is a net gain in fitness. Age-related deficit accumulation is highly characteristic, and can be modeled as a stochastic process with readily interpretable parameters.
AB - As people age, they accumulate deficits. The more deficits they accumulate, the greater their vulnerability, which can be expressed as the probability to accumulate even more deficits, or to die. The probability of death is known to be exponentially related to the number of deficits. Using data from elderly (aged 65+ years) participants in the Canadian Study of Health and Aging (n = 9008), we investigated the relationship between the number of deficits and the change in the number of deficits over two successive 5 year intervals. We show that the probabilities of changes in the number of deficits, in relation to baseline, are well fitted (R2 > 0.98) by a simple distribution, with two parameters. The model suggests a maximum to deficit accumulation, and illustrates no level of deficit accumulation at which there is a net gain in fitness. Age-related deficit accumulation is highly characteristic, and can be modeled as a stochastic process with readily interpretable parameters.
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U2 - 10.1016/j.mad.2006.01.007
DO - 10.1016/j.mad.2006.01.007
M3 - Article
C2 - 16519921
AN - SCOPUS:33645850908
SN - 0047-6374
VL - 127
SP - 490
EP - 493
JO - Mechanisms of Ageing and Development
JF - Mechanisms of Ageing and Development
IS - 5
ER -