Serum folic acid is reduced in patients with Alzheimer's disease

Abstract

Background: Complex B vitamin deficiency has been associated to cognitive impairment and dementing disorders in the elderly. Objective: This work aims to assess whether patients with Alzheimer's disease (AD) and mild cognitive impairment (MCI) have lower levels of folic acid and cobalamin (vitamin B 12) compared to age and gender-matched controls. Methods: One hundred and forty six elderly subjects (40 AD, 56 MCI and 49 healthy older adults) were recruited for this study. Serum folic acid and vitamin B 12 levels were measured by electrochemoluminescence. Results: Compared to MCI and healthy controls a statistically significant reduction in serum concentrations of folic acid in AD patients was found (p = 0.02). This result remained statistically significant after controlling for socio-demographic and cognitive performance variables (p = 0.01). No significant differences were found in serum concentrations of vitamin B 12 in patients with AD, MCI and healthy controls. No significant changes in hematologic parameters were observed across these diagnostic groups. Discussion: The present study provides additional evidence that folic acid is reduced in patients with AD and reinforces the importance of nutritional changes, in particular the one-carbon metabolism, in the physiopathology of AD.