A sense of purpose in life may reduce the risk for cerebral infarcts by approximately half, according to data published in the April issue of Stroke. Purpose in life is a psychosocial concept that involves having meaning and being directed toward goals, said the researchers. The association between it and cerebral infarcts appears to be independent of vessel disease.
“Mental health, in particular positive psychological factors such as having a purpose in life, is emerging as a very potent determinant of health outcomes,” said Patricia Boyle, PhD, Associate Professor of Behavioral Sciences at the Rush Alzheimer’s Disease Center of Rush University Medical Center in Chicago. “Clinicians need to be aware of patients’ mental state and encourage behaviors that will increase purpose and other positive emotional states.”
Comparing Psychologic and Neurologic Well-Being
Dr. Boyle and colleagues analyzed data for 453 participants in the Rush Memory and Aging Project, an ongoing clinical–pathologic cohort study of aging and dementia. Eligible participants responded annually to a modified 10-item measure derived from Ryff’s and Keyes’s scales of Psychological Well-Being to assess their degree of purpose in life. After patients died, investigators blinded to clinical information conducted uniform neuropathologic examinations during autopsy to identify macroscopic infarcts and microinfarcts. The researchers used ordinal logistic regression analysis to examine the association between cerebral infarcts and the participants’ first valid scores of purpose.
Approximately 68% of participants were female. Patients’ mean age at baseline was approximately 84, and mean age at death was about 90. Mean score on the measure of purpose in life was 3.5 out of a possible 5 points.
Of the 453 participants, 114 (25.3%) had clinical stroke and 216 had macroscopic or microinfarcts at autopsy (47.7%). Seventy-six participants (16.8%) had one macroscopic infarct, and 78 (17.2%) had two or more macroscopic infarcts. In addition, 81 participants (17.9%) had one microinfarct, and 47 (10.4%) had two or more microinfarcts.
Association Depended on Lacunar Infarcts
After the investigators adjusted their data analysis for demographics, they found that greater purpose in life was associated with lower odds of macroscopic infarcts. A one-point increase of the score for purpose in life reduced the odds of having one or more macroscopic infarcts by approximately 50%. The researchers did not, however, find an association between purpose and microinfarcts, nor did they find any difference in purpose according to gender.
On average, purpose in life declined slightly over time for the population. Adjusting the data for the individual-specific change in purpose in life did not affect the association between purpose and infarcts. “These results support the relatively traitlike property of purpose in life,” said the investigators.
Furthermore, a greater purpose in life was associated with fewer subcortical macroscopic infarcts, but not with cortical macroscopic infarcts. The association was significant only with respect to lacunar infarcts, particularly gray matter lacunar infarcts. In addition, purpose in life was not associated with the measure of arteriolosclerosis or atherosclerosis. Together with previous data, the current study “suggests that purpose in life is protective for silent infarcts, as well as clinical stroke,” said Dr. Boyle.
“The neurobiologic basis of the protective effect of purpose in life and other psychosocial constructs is complex and poorly understood,” she continued. “First, purpose may reduce the risk of infarcts by promoting healthy lifestyles. … Second, purpose may directly be implicated in neuroendocrine function.” Understanding the mechanistic pathway will require future research, she added.
“Purpose in life differs for everyone, and it is important to be thoughtful about what motivates you, such as volunteering, learning new things, or being part of the community, so you can engage in rewarding behaviors,” said Lei Yu, PhD, the lead author and Assistant Professor of Neurological Sciences at the Rush Alzheimer’s Disease Center.
—Erik Greb