Association of Adherence to a MIND-Style Diet With the Risk of Cognitive Impairment and Decline in the REGARDS Cohort.

Background And Objectives: Diet may influence the development of cognitive impairment and affect cognitive decline, but whether this relationship varies between Black American and White American people is unclear. This study examined the association of Mediterranean-Dietary Approaches to Stop Hypertension Intervention for Neurodegenerative Delay (MIND) and incident cognitive impairment and cognitive trajectories in a biracial prospective cohort study.

Methods: Using data derived from the Food Frequency Questionnaire in the REasons for Geographic and Racial Differences in Stroke study, we compared MIND diet adherence with incident cognitive impairment and cognitive trajectory in Black participants and White participants. Logistic regression was used to model MIND diet score (continuous variable and using tertiles) and incident cognitive impairment after adjusting for age, sex, race, region, education, income, total energy, hypertension history, dyslipidemia, diabetes, estimated glomerular filtration rate, ischemic heart conditions, atrial fibrillation, and lifestyle factors including sedentary, obesity, and smoking. Mixed-effects models were used to examine the association between cognitive trajectory and MIND diet adherence.

Results: Dietary data to calculate the MIND diet score and cognitive data were available on 14,145 participants with a mean age of 64 years (SD 9.0 years) that was 56.7% female. Greater MIND diet adherence was associated with a decreased incidence of cognitive impairment (odds ratio [OR] 0.96, 95% CI 0.93-0.99, = 0.02) after adjusting for all covariates. In the fully adjusted model, greater MIND diet adherence was associated with decreased risk of cognitive impairment in female participants (OR 0.92, 95% CI 0.89-0.96, < 0.001) but not in male participants (OR 1.01, 95% CI 0.97-1.06, = 0.64). In all models, greater MIND diet adherence was associated with decreased risk of cognitive decline. MIND diet adherence was a better predictor of cognitive decline in Black participants (β = 0.04, SE = 0.007, < 0.001) than in White participants (β = 0.03, SE = 0.004, < 0.001).

Discussion: Greater MIND diet adherence was associated with decreased risk of cognitive impairment in female participants but not male participants, with no difference between Black participants and White participants. However, MIND diet adherence was a better predictor of cognitive trajectory in Black participants than in White participants.