Résumé
Background: A sense of purpose in life has been associated with healthier cognitive outcomes across adulthood, including risk of dementia. The robustness and replicability of this association, however, has yet to be evaluated systematically.
Objective: To test whether a greater sense of purpose in life is associated with lower risk of dementia in four population-based cohorts and combined with the published literature.
Methods: Random-effect meta-analysis of prospective studies (individual participant data and from the published literature identified through a systematic review) that examined sense of purpose and risk of incident dementia.
Results: In six samples followed up to 17 years (four primary data and two published; total N = 53,499; n = 5,862 incident dementia), greater sense of purpose in life was associated with lower dementia risk (HR = 0.77, 95% CI = 0.73-0.81, p < 0.001). The association was generally consistent across cohorts (I-2 = 47%), remained significant controlling for clinical (e.g., depression) and behavioral (e.g., physical inactivity) risk factors, and was not moderated by age, gender, or education.
Conclusion: Sense of purpose is a replicable and robust predictor of lower risk of incident dementia and is a promising target of intervention for cognitive health outcomes.