Having a purpose in life — having meaning and direction — is linked with better mental health and happiness, and even longevity. Now, researchers have found that it is also linked with a lower risk of incident Alzheimer's disease.
In a study published in the March issue of Archives of General Psychiatry, researchers at Rush University Medical Center found that people who have a sense of purpose in life are less likely to develop Alzheimer's disease or even mild cognitive impairment.
"Alzheimer's disease is one of the most dreaded consequences of aging, and finding risk factors that we can modify to prevent, or at least delay, the disease is a top public health priority," said Patricia Boyle, PhD, principal investigator and a researcher in the Rush Alzheimer's Disease Center. "Our findings may provide precisely this opportunity—a treatment target for interventions aimed at enhancing the health and well-being of older adults. With behavioral strategies, we can help older adults identify personally meaningful activities and engage in goal-directed behaviors, and possibly help them ward off the symptoms of Alzheimer's."
More than 900 community-dwelling older persons who did not have dementia, all of them part of the Rush Memory and Aging Project, participated in the study. At baseline, a standard psychological assessment survey was used to gauge whether they had a sense of purpose in life, that is, whether they felt that life had meaning and that their behavior was guided by goals and intentions.
After an average of four years and a maximum of seven years of annual follow-up clinical evaluations, 155 of 951 participants (16.3 percent) developed Alzheimer’s disease. Controlling for other related variables, the researchers found that greater purpose in life was associated with a substantially reduced risk of developing Alzheimer’s disease, as well as a reduced risk of mild cognitive impairment and a slower rate of cognitive decline.
Specifically, individuals with a score of 4.2 out of 5 (90th percentile) on the purpose-in-life measure were approximately 2.4 times more likely to remain free of Alzheimer’s disease than individuals with a score of 3.0 (10th percentile).
"Why, biologically, having a sense of purpose in life reduces the risk of Alzheimer's is not clear," Boyle said. "There are some data linking purpose in life with immune function and vascular health, so it is possible that these systems play a mediating role. But at this point, we do not know that they do."
Other researchers at Rush involved in the study were Dr. Aron Buchman, Lisa Barnes, PhD, and Dr. David Bennett. Funding for the study was provided by the National Institute on Aging the Illinois Department of Public Health, and the Robert C. Borwell Endowment Fund.