The population of U.S. adults older than 85 years is expected to triple from 5.4 million to 19 million between 2008 and 2050. While many people do live into their eighth and ninth decades independently and free of disability, the end-of-life course is increasingly likely to be marked by disability, according to the study background.
Alexander K. Smith, M.D., M.S., M.P.H., of the University of California, San Francisco, and colleagues used a nationally representative sample of older Americans to determine national estimates of disability during the last two years of live. Disability was defined as needing help with at least one of the following activities of daily living: dressing, bathing, eating, transferring, walking across the room and using the toilet. The study included 8,232 decedents whose average age at death was 79 years. Of the decedents, 52 percent were women.
According to the study results, the prevalence of disability increased from 28 percent two years before death to 56 percent in the last month of life. Those adults who died at the oldest ages were more likely to have a disability two years before death (50-69 years, 14 percent; 70-79 years, 21 percent; 80-89 years, 32 percent; 90 years or more, 50 percent). Disability was more common among women two years before death (32 percent) than among men (21 percent), the results indicate.
"Our data do raise the question of whether it makes sense to sell the public a view of aging that purports that it is reasonable to expect to both live a long life and remain free of disability throughout life. Our findings add to the evidence that those who live to advanced ages will spend greater periods of time in states of disability than those who die at younger ages," the study concludes.