The Entropy of Health and Disease: Dementia in Canada

The object of this paper is to combine two concepts which have developed on the interface between public health and demography: health expectancy and the analysis of linkage in demographic models. The paper addresses in the general case the question: what are the marginal effects of changes in incidence or mortality rates on the expectation of life with and without a particular irreversible non-communicable disease or type of disability? A simple model of disease in a population is described and general solutions for the two components of the expectation of life are obtained.... It is shown that under certain conditions the entropy of the expectation of disease free life with respect to changes in incidence can be approximated by an extension of Sullivans index. Data on dementia among elderly Canadians obtained from the Canadian Study of Health and Aging are used for illustration. (EXCERPT) (SUMMARY IN FRE)