A bloodâ based nutritional risk index explains cognitive enhancement and decline in the multidomain Alzheimer prevention trial

IntroductionMultinutrient approaches may produce more robust effects on brain health through interactive qualities. We hypothesized that a bloodâ based nutritional risk index (NRI) including three biomarkers of diet quality can explain cognitive trajectories in the multidomain Alzheimer prevention trial (MAPT) over 3â years.MethodsThe NRI included erythrocyte nâ 3 polyunsaturated fatty acids (nâ 3 PUFA 22:6nâ 3 and 20:5nâ 3), serum 25â hydroxyvitamin D, and plasma homocysteine. The NRI scores reflect the number of nutritional risk factors (0â 3). The primary outcome in MAPT was a cognitive composite Z score within each participant that was fit with linear mixedâ effects models.ResultsEighty percent had at lease one nutritional risk factor for cognitive decline (NRI â ¥1: 573 of 712). Participants presenting without nutritional risk factors (NRI=0) exhibited cognitive enhancement (β = 0.03 standard units [SU]/y), whereas each NRI point increase corresponded to an incremental acceleration in rates of cognitive decline (NRIâ 1: β = â 0.04 SU/y, P = .03; NRIâ 2: β = â 0.08 SU/y, P < .0001; and NRIâ 3: β = â 0.11 SU/y, P = .0008).DiscussionIdentifying and addressing these wellâ established nutritional risk factors may reduce ageâ related cognitive decline in older adults; an observation that warrants further study.Highlightsâ ¢Multiâ nutrient approaches may produce more robust effects through interactive propertiesâ ¢Nutritional risk index can objectively quantify nutritionâ related cognitive changesâ ¢Optimum nutritional status associated with cognitive enhancement over 3â yearsâ ¢Suboptimum nutritional status associated with cognitive decline over 3â yearsâ ¢Optimizing this nutritional risk index may promote cognitive health in older adultsPeer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/152935/1/trc2jtrci201911004.pd