Mortality postponed and the unmasking of age-dependent non-fatal conditions

Abstract

Mortality occurs at older ages in our growing and salubrious population. At present, fewer than 20% of all deaths, in Sweden, occur before age 65 with 18% of the Swedish population 65 and over. In the United States, 24% of deaths occur before age 65 with only 12% of the population age 65 and over. All countries in the developed world will have approximately 20% of their populations age 65 and over by about 2020. At that time, the percentage of deaths occurring prior to age 65 should range from 14%–16%. Thus future gains in morbidity and mortality will be influenced, to a lesser extent, by events prior to age 65 and prevention and health promotion strategies post age 65 become increasingly important. Active life expectancy, a developing concept, refers to the years lived in good health with no functional limitations. The period after active life expectancy consists of years of compromised health and well being. At present, each year gained of active life expectancy incurs almost four years of compromised health. A group of age-dependent non-fatal conditions are largely responsible for increased prevalence of social and physical deficits with age. These include dementia, osteoarthritis, diminished hearing and visual acuity, incontinence, depression, widowhood, isolation and institutionalization. Age-specific incidence of most of these conditions is unknown. There is little evidence, however, that adding years to life has postponed their age at onset. For these conditions, postponement is the major mechanism of prevention. We are attempting to construct time trends concerning the age-specific incidence and the ability to postpone age-dependent conditions. Unless we succeed in delaying onset, morbidity will inevitably expand as longevity increases. (Aging 2:283-289,1990)