Take an aging population and a measure of function, and on average that measure will decline over time. That is degenerative aging in a nutshell, a loss of function, eventually including the very important function of staying alive. Within the environment of an average decline, however, it is possible to find individuals who manage to improve function between time points. Consider that it is well demonstrated that even very old people can improve capacity and reduce mortality risk by undertaking programs of structured exercise and strength training, for example. Few of us are exercising to an optimal level.
A widespread assumption exists among scientists, health care providers, and the public that later life is a time of inevitable and universal cognitive and physical decline. This assumption is likely due to considering older persons who improve to be exceptions, and the reliance on aging-health measures that do not allow for improvement. In contrast, we utilized a measure that allowed for an upward trajectory to occur. Our objective was to examine whether a meaningful number of older persons improve with this measure and, if so, to examine whether a promising modifiable culture-based variable, positive age beliefs, contributes to this improvement.
Individuals 65 years and older, who participated in a nationally representative longitudinal study, had their physical health assessed by walking speed and their cognitive health assessed by a global performance measure. We calculated the percentage of the sample that showed improvement in each domain from baseline to the last measurement up to 12 years later. We also examined whether a positive-age-belief measure predicted this improvement in regression models. It was found that 45.15% of persons improved in cognitive and/or physical function over this period, and positive age beliefs predicted these two types of improvement, both with and without adjusting for relevant covariates.
