Association of Life’s Crucial 9 with cognitive function and stroke risk: insights from the NHANES 2011–2014 study

BACKGROUND: Cognitive impairment and stroke constitute major health challenges for the aging global population, adversely impacting quality of life and increasing healthcare burdens. The American Heart Association's "Life's Essential 8" (LE8) framework has served as a key tool for evaluating cardiovascular health (CVH); however, it omits mental health, a critical factor influencing both cognitive function and stroke risk. The introduction of "Life's Crucial 9" (LC9), which includes depressive symptoms, provides a more comprehensive approach. This study investigates the relationship between LC9, cognitive function, and stroke risk. METHODS: Utilizing the National Health and Nutrition Examination Survey (NHANES) dataset from 2011 to 2014, cross-sectional data from 2,327 participants were analyzed. Stratified analyses were performed according to demographic and health-related factors. A Restricted Cubic Spline (RCS) model was employed to examine potential threshold effects. Additionally, weighted linear regression models were used to evaluate cognitive performance, and logistic regression models were applied to assess stroke risk. RESULTS: Higher LC9 scores were positively associated with better cognitive function and lower odds of stroke. Within the cognitive function analysis, higher LC9 scores were significantly associated with superior performance on the Digit Symbol Substitution Test (DSST) (β = 0.18, 95% CI: 0.11- 0.26, P < 0.001). In the stroke analysis, individuals with higher LC9 scores exhibited decreased odds of experiencing a stroke (OR = 0.97, 95% CI: 0.95-0.99, P = 0.005). RCS analysis identified a non-linear relationship between LC9 scores and the odds of stroke, with the greatest decreases in stroke odds observed at lower LC9 scores, plateauing around a score of 70. CONCLUSIONS: Higher LC9 scores are associated with better cognitive function and lower odds of stroke. These findings suggest that incorporating mental health metrics, such as depression, into cardiovascular health assessments enhances the predictive power for cognitive outcomes and stroke prevention.