Dietary patterns, cardiometabolic and brain health in the PREVENT Dementia Cohort

Abstract

AbstractBackgroundThe Mediterranean diet (MedDiet) has been associated with better cardiometabolic and brain health. Research has suggested differences in these associations between men and women, with men typically reported to benefit more from higher MedDiet adherence. However there remains a lack of research in this area in non‐Mediterranean countries. This study aimed to explore cross‐sectional associations between MedDiet adherence in the PREVENT Dementia cohort (UK and Ireland), stratified by sex.MethodAfter deriving scores to quantify adherence to the MedDiet (MEDAS, MEDAS continuous and Pyramid), we used linear regression and linear mixed effects models to test for associations between the MedDiet scores, cardiometabolic health (blood pressure, BMI, glycemia, cholesterol, triglycerides) and brain health (white matter hyperintensity volume (WMHV), cortical thickness, hippocampal subfield volumes, cognition). Propensity scores were calculated to strengthen causality inferences from the data, and used as covariates along with total energy intake and Western diet scores.ResultWe included 533 participants, mean age 51.25 (±5.40) years, majority women (60.0%). Higher MedDiet scores (MEDAS data presented) were associated with lower blood pressure (systolic ß: ‐1.16, p:0.009; diastolic ß: ‐1.00, p<0.001) and BMI (ß: ‐0.53, p<0.001). There were significant interactions between MedDiet and sex for diastolic blood pressure and hip‐to‐waist ratio. When stratified by sex, women had significant positive associations between MedDiet scores and blood pressure (systolic ß: ‐1.45, p: 0.006; diastolic ß: ‐1.29, p<0.001), BMI (ß: ‐0.51, p: 0.02) and glycemia (Pyramid only: ß: ‐0.11, p: 0.02), whereas men only had a significant association with BMI (ß: ‐0.45, p: 0.02) (Figure 1). There were no significant associations between dietary scores and any markers of brain health. An exploratory path analysis found a significant mediation between the Pyramid MedDiet score, pulse pressure and WMHV (Figure 2), which was only seen in women.ConclusionThere were significant associations between higher MedDiet scores and better cardiometabolic health, particularly for women. There were no direct associations with brain health outcomes, however a path analysis suggested a mediating effect of pulse pressure between the MedDiet and WMHV. Sex‐stratified nutritional guidelines to support better cardiometabolic health, may lead to better brain health and warrant further investigation.