Adherence to nutritional recommendations and subsequent cognitive performance: findings from the prospective...

Few studies have investigated the long-term effect of overall nutritional recommendations on cognition.

In a French cohort of middle-aged adults, we evaluated the association between the French National Nutrition and Health Program (Program National Nutrition Santé) Guideline Score (PNNS-GS) assessed at baseline and cognitive performance evaluated 13 y later.

The PNNS-GS was estimated at baseline (1994-1996) (maximum score: 15 points) in 2135 subjects in the SU.VI.MAX (Supplementation with Antioxidant Vitamins and Minerals) study. We assessed cognitive performance of subjects in 2007-2009 via a battery of 4 neuropsychologic tests that included phonemic and semantic fluency, the RI-48 (rappel indicé-48 item) cued-recall test, the trail-making test, and forward and backward digit spans. A principal components analysis was performed to account for correlations in test scores. Multivariate linear regression models or analyses of covariance were also performed.

In a multivariate model, we observed a positive association between the PNNS-GS and the cued-recall test and semantic and phonemic fluency tasks, whereas no association was observed with digit spans. The principal components analysis revealed 2 factors interpreted as reflecting verbal memory and executive functioning. Better adherence to nutritional recommendations was significantly associated with the verbal memory factor (β = 0.41; 95% CI: 0.17, 0.64), whereas no association was shown with the executive functioning factor. Removing specific components from the PNNS-GS did not modify the findings.

This study suggests that strong compliance with nutritional recommendations in midlife is associated in elderly individuals with better verbal memory, which is a cognitive domain that is particularly vulnerable to pathologic aging and Alzheimer disease. This trial was registered at clinicaltrials.gov as NCT00272428.