Purpose in Life and Motoric Cognitive Risk Syndrome: Replicable Evidence from Two National Samples.

BACKGROUND/OBJECTIVES: Motoric cognitive risk (MCR) syndrome is characterized by cognitive complaints and slow gait speed in the absence of dementia. Consistent evidence indicates that it predicts dementia and premature mortality. Less is known about its antecedents, particularly the role of psychological function. Purpose in life is an aspect of well-being that reflects a goal-oriented and -driven life that has been implicated in cognitive aging. We aimed to examine the cross-sectional association between purpose in life and MCR and to test the hypothesis that purpose is associated with a lower risk of new cases of MCR over an up to 12-year follow-up.

DESIGN: Cross-sectional and longitudinal multi-cohort design.

SETTING: Health and Retirement Study (HRS) and the National Health and Aging Trends Study (NHATS).

PARTICIPANTS: A total of 6,785 individuals from the HRS and 5,665 from the NHATS.

MEASUREMENTS: Participants reported on their purpose in life and cognitive complaints and completed a walking speed assessment. Cognitive complaints and walking speed were assessed again up to 12 years later in HRS and up to 7 years later in NHATS.

RESULTS: Higher purpose in life was associated with a 33% lower risk of MCR concurrently (meta-analytic odds ratio = .75; 95% confidence interval [CI] = .62-.90; P = .002) and an about 26% lower risk of incident MCR longitudinally (meta-analytic hazard ratio = .77; 95% CI = .70-.84; P < .001). These associations were significant in each sample, were independent of sociodemographic covariates, and persisted after controlling for personality and health-related factors (depressive symptoms, physical activity, disease burden).

CONCLUSION: Purpose in life is associated with a lower risk of incident MCR, an association that was replicated in two independent samples. Purpose is a malleable aspect of psychological function that is a promising target of intervention for healthier cognitive aging.