Changes with age in the distribution of a frailty index

被引:125
作者
Rockwood, K [1 ]
Mogilner, A [1 ]
Mitnitski, A [1 ]
机构
[1] Dalhousie Univ, Dept Med, Div Geriatr Med, Halifax, NS B3H 1C6, Canada
基金
加拿大健康研究院;
关键词
ageing; frailty index; rate of mortality; sex differences; gamma density; heterogeneity; requisite variety;
D O I
10.1016/j.mad.2004.05.003
中图分类号
Q2 [细胞生物学];
学科分类号
071009 ; 090102 ;
摘要
Models of human mortality include a factor that summarises intrinsic differences in individual rates of ageing, commonly called frailty. Frailty also describes a clinical syndrome of apparent vulnerability. In a representative, cross-sectional, Canadian survey (n = 66,589) we calculated a frailty index as the mean accumulation of deficits and previously showed it to increase exponentially with age. Here, its density function exhibited a monotonic change in shape, being least skewed at the oldest ages. Although the shape gradually changed, the frailty index was well fitted by a gamma distribution. Of note, the variation coefficient, initially high, decreased from middle age on. Being able to quantify frailty means that health risks can be summarised at both the individual and group levels. (C) 2004 Elsevier Ireland Ltd. All rights reserved.
引用
收藏
页码:517 / 519
页数:3
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