Blood nutrient concentrations may reflect cognitive function in the aging brain
MedWire News: Nutritional biomarkers may be linked to psychometric and imaging indices of brain health in elderly patients, according to research published in the journal Neurology.
Gene Bowman (Oregon Health and Science University, Portland, USA) and colleagues investigated 30 biomarkers of diet in the Oregon Brain Aging Study cohort for a possible relationship with cognitive function and magnetic resonance imaging (MRI) data. They constructed nutrient biomarker patterns to assess this relationship.
"Nutrient biomarker patterns may afford complementary ways to examine the influence of food mixtures as consumed, independent of limitations described for current food frequency questionnaires and 24-hour dietary recalls," write Christy Tangney and Nikolaos Scarmeas from Columbia University in New York, USA, in an accompanying editorial.
Bowman and team's study involved 104 dementia-free participants with a mean age of 87 years. Cognitive function was measured using neuropsychologic tests that assessed memory, attention, language, processing speed, and visual-spatial, executive function, and global function. Volumetric data were obtained from MRI scans of the brain.
Two biomarker patterns were associated with improved cognitive and total brain volume (TBV); one was high in vitamins B (B1, B2, B6, folate, and B12), C, D, and E (BCDE pattern), and the other was high in marine ω-3 fatty acids.
The pattern with high levels of trans fat was associated with a reduced cognitive function and TBV.
The relationship between BCDE pattern and cognitive function did not persist after TBV was included in the model, which Tangney and Scarmeas suggest shows "that the contribution to cognitive performance is not entirely explicable by structural changes or cerebral atrophy."
The researchers suggest that these biomarker patterns translate to two types of diet. The BCDE pattern and ω-3 pattern would typically relate to a diet rich in dark green leafy and cruciferous vegetables, fruit, and fish, whereas the pattern high in trans fat reflects a diet of bakery, fried food, margarine spread, red meat, and offal.
Trans fat consumption has been linked to increased cardiovascular risk, systematic inflammation, and endothelial dysfunction, which may influence cognitive function, but there may also be an independent interaction, say Bowman and co-workers.
Finally, they outline targets for future research: "The significance of these [nutritional biomarker patterns] at different stages of cognitive status are unknown. These studies will decipher the key nutrient combinations and the population best suited for intervention studies."
By Chloe McIvor