Association of adherence to high-intensity physical activity and the Mediterranean-dietary approaches to stop hypertension intervention for neurodegenerative delay diet with cognition: A cross-sectional study

Background: Prevention is a priority in the absence of a cure for dementia. Physical activity and a neuroprotective diet such as the Mediterranean-Dietary Approaches to Stop Hypertension Intervention for Neurodegenerative Delay (MIND) diet are healthy lifestyle behaviors that may slow the onset of dementia. However, research on the relationship between the combination of physical activity and the MIND diet and cognition is rare. Objectives: The purpose of this study was to investigate whether the combination of high-intensity physical activity and the MIND diet is associated with better cognition compared with either behavior alone or neither behavior. Design: A population-based, cross-sectional study was conducted using data from the Health and Retirement Study. Methods: Using information from a total of 3463 participants (age 68.0 ± 10.0 years), multivariate linear regression models and binary logistic regression models with interaction terms between high-intensity physical activity (PA) and the MIND diet (MIND) were used to assess associations of PA and MIND with global cognition and odds of cognitive decline. Group comparisons were conducted among four groups: PA −/MIND −, PA +/MIND −, PA −/MIND +, and PA +/MIND +. Results: PA +/MIND − did not predict cognitive outcomes (versus PA −/MIND −). PA −/MIND + was associated with better global cognition (mean difference [d] = 0.81; 95% confidence interval [CI] = 0.50–1.11; p < 0.001) and lower odds of cognitive decline (odds ratio [OR] = 0.68; 95% CI = 0.54–0.86; p = 0.001) (versus PA −/MIND −). PA +/MIND + predicted better global cognition (d = 0.98; 95% CI = 0.59–1.36; p < 0.001) and lower odds of cognitive decline (OR = 0.69; 95% CI = 0.50–0.94; p = 0.004) (versus PA −/MIND −). PA +/MIND + was associated with better global cognition (d = 0.60; 95% CI = 0.08–1.12; p < 0.001), but did not predict lower odds of cognitive decline (versus PA +/MIND −). PA +/MIND + did not predict cognitive outcomes (versus PA −/MIND +). Conclusions: Combining high-intensity physical activity and the MIND diet was associated with better cognitive health than high-intensity physical activity alone or non-adherence to both behaviors. To potentially exert additive effects, it will be important to encourage these two healthy habits. More research on the role of combined physical activity and dietary change is necessary to further inform policy and clinical guidance.