Aging, Illness, and Health Policy: Implications of the Compression of Morbidity

The national illness burden has shifted over recent decades from acute to chronic illness and from younger to older individuals [1,2]. The problems of chronic illness mix with and finally give way to senescent problems. Our future population will contain substantially more older individuals, as the birth cohorts of the 1920s and 1930s now approaching their seniority are larger than previous cohorts, and average life expectancy also is increasing. These commonly made observations lead some to postulate a dark future of increasing dependency, worsening health, and spiraling health care costs. The ability of society to pay everincreasing costs for ever more vegetative existence has been called into severe question. However, these somber predictions are not rooted in current knowledge of chronic disease and senescence, and they are not necessarily accurate. There is a much more hopeful paradigm, that of the "compression of morbidity" [1—10]. Rather than assuming that disease is fixed and the life span indefinitely extensible, the compression of morbidity thesis notes that the species' life span is finite and that the onset of chronic disease is relatively easily delayed. Thus, the period (in each individual life) from onset of chronic infirmity to death may be shortened, with both individual and social benefit.