Abstract TP171: Purpose in Life and Risk of Cerebral Infarction

Abstract

Background: Purpose in life (PIL), the sense that life has meaning and direction, is associated with a reduced risk of Alzheimer’s disease, incident disability, and mortality among community-dwelling older persons. Objective: To test the hypothesis that PIL is associated with reduced risk of cerebral infarction. Methods: Longitudinal clinical-pathologic cohort study. Subjects were from the Rush Memory and Aging Project (MAP). Older persons without dementia completed a standard measure of PIL using a structured interview and 10-item scale derived from Ryff’s Scales of Psychological Well-Being. The number of chronic gross & microscopic cerebral infarctions (each expressed as 0,1, or >1) were identified on a uniform neuropathologic examination blinded to clinical information. Semiquantitative assessments (0 to 3) of atherosclerosis and lipohyalinosis were also performed. The associations of PIL with cerebral infarction, cerebral vessel pathology were examined using linear regression and mixed models adjusted for age, sex, & education. Results: 347 subjects had both PIL and brain pathology assessed. Scores on the measure of PIL ranged from 2.1 to 5.0 (mean 3.5, SD 0.48). On postmortem examination, gross/macroscopic cerebral infarcts were found in 112 (32.28%) persons (51 with 1, 61 with >1) and microinfarcts were found in 84 (24.21%) (54 with 1, 30 with > 1). PIL was associated with a reduced odds of gross cerebral infarcts (estimate = 0.57, SE = 0.24, p = 0.02) and there was a trend (p = 0.096) toward an association with microinfarcts. PIL was not related to the type or severity of cerebral vessel pathology. In subsequent logistic regression models, the association of PIL with gross cerebral infarcts persisted after adjustment for depressive symptoms, BMI, smoking, diabetes, and measures of socioeconomic status. However, the association of PIL with gross infarcts was reduced to a trend (estimate = 0.46, SE = 0.26, p = 0.08) after adjustment for systolic blood pressure, suggesting partial mediation. Conclusions: Lower PIL may be a risk factor for macroscopic cerebral infarction in old age without a direct effect on atherosclerotic cerebral vessel pathology.