ROLE OF FOLATE AND THE METABOLICALLY RELATED B-VITAMINS IN BRAIN HEALTH IN OLDER ADULTS: THE TUDA STUDY

Background and objectives: Folate and the metabolically related B-vitamins involved in one-carbon metabolism may be important for maintaining brain health in aging but few studies have investigated the biomarker status of all relevant B-vitamins. The aim of this study was to examine the role of folate, vitamin B12, vitamin B6 and riboflavin in mental and cognitive health in older adults. Methods: Participants were recruited (n 5186) to the Trinity, Ulster, Department of Agriculture (TUDA) Ageing Cohort study in 2008-2012, from across the Island of Ireland; of these, a sub-sample (n 587) of participants were reinvestigated 5 years after the initial TUDA study. Cognition was assessed using the Mini- Mental State Examination (MMSE), the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and the Frontal Assessment Battery (FAB). Depression and anxiety were assessed using the Centre for Epidemiologic Studies Depression (CES-D) and the Hospital Anxiety and Depression (HADS) scales. Biomarkers of all the relevant B-vitamins were determined. Results: At baseline, poor B-vitamin status (i.e. lowest 20%) was associated with an increased risk of depression (by 47-78%) for folate (p 0.003), vitamin B6 (p 0.034) and riboflavin (p 0.011), whereas only vitamin B6 deficiency was associated with anxiety (p 0.010) and cognitive dysfunction (p ≤0.001). Furthermore, at the 5 year follow up assessment, lower biomarker status at baseline (i.e. below median value) of vitamin B6 and riboflavin, but not folate or vitamin B12, were significant predictors of the rate of cognitive decline, as measured by change in MMSE (vitamin B6 p 0.020) and RBANS (vitamin B6 p 0.008; riboflavin p 0.018). Concentrations of all B-vitamin biomarkers increased significantly with increasing intake of fortified foods and with supplement use, while non-consumers of fortified foods or supplements had the lowest status of all B-vitamin biomarkers. Conclusions: These results suggest that better B-vitamin status can have a positive impact on mental and cognitive health older adults. Optimization of B-vitamin status, via fortified foods or supplements, may offer a means of protecting brain health in aging.