- Open Access
Applying a cumulative deficit model of frailty to dementia: progress and future challenges
© Anstey and Dixon; licensee BioMed Central Ltd. 2014
- Published: 26 November 2014
The article by Song and colleagues presents findings from the Canadian Study of Health and Aging showing that the accumulation of health deficits, defined dichotomously and unqualified by severity or domain, predicted late-life dementia independent of chronological age. We identify strengths of this model, and also areas for future research. Importantly, this article broadens the perspective of research into measuring risk of dementia from focusing on specific neuropathological markers of dementia subtypes, to mechanisms underlying more general bodily vitality and health, as well as dysfunctions in repair. This work places late-life dementia in a new context, influenced more broadly by health maintenance, and less by specific neurological disease. While useful at a global level, the lack of specificity of this approach may ultimately limit its application to individual patients because without linking risk to etiology, assessment does not indicate an intervention. Ultimately, the article has value for stimulating debate about approaches to risk identification and risk reduction, suggesting that the current focus on cardiometabolic risk factors may be too limited.
- Frailty Index
- Health Deficit
- Deficit Index
- Cascade Theory
Importantly, Song and colleagues  broaden the perspective of research into measuring risk of dementia from focusing on specific causes of neuropathological markers of dementia subtypes, to mechanisms underlying more general bodily vitality and health, as well as dysfunctions in repair. This places late-life dementia in a new context, influenced more broadly by health maintenance, and less by specific neurological disease. This approach may benefit from further integration - rather than separation - into the emerging multi-variable and mechanism-related approaches to biomarker and risk factor research. An intriguing question is whether the identification of a poor repair mechanism would explain the occurrence of the individual risk factors (or vice versa). It would also be interesting to know how the frailty index relates to genetic markers of longevity (and neurodegenerative disease). Most importantly, it would be useful to discover whether an intervention to improve ‘repair mechanisms’ could have widespread benefits across multiple cognitive health conditions or is better supplemented by specific mechanism-related therapeutics.
KJA is funded by NHMRC Research Fellowship # 1002560. RAD is supported in part by a Canada Research Chair (Tier 1). The research is supported by the Dementia Collaborative Research Centres (to KJA) and the National Institutes of Health (National Institute on Aging, R01 AG008235, to RAD).
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