Advancing age, impending death, and declining cognition

Abstract

Loss of cognition in late life traditionally has been viewed from a developmental perspective much like the growth of cognitive ability in early life. Beginning in the 1960s, Kleemeier1 and others instead hypothesized that cognition declines in the last few years of life and that late life cognitive decline is due more to this terminal drop than to growing older. Although the hypothesis stimulated considerable scientific interest, little supporting data emerged, and a 2002 review concluded: “It is still not clear whether terminal change exists.”2 However, most of the available studies lacked the ingredients needed to test the hypothesis: multiple assessments of cognition over a several year period proximate to death in individuals with a wide spectrum of cognitive ability.2,3 Several studies with these design elements have been published in the last 5 years,3–7 and in contrast to earlier research, their results have generally …