Alzheimer’s Disease (AD): Vitamin B12 deficiency is associated with lower Mini‐Mental State Exam (MMSE) scores

Abstract

AbstractBackgroundAlzheimer’s Disease (AD) is the leading cause of dementia in the elderly and several lines of evidence indicate that B12 hypovitaminosis is linked to AD. The biochemical pathways involved in AD that are affected by vitamin B12 are APP processing, Aβ fibrillization, Aβ‐induced oxidative damage as well as tau hyperphosphorylation and tau aggregation.Method103 outpatients with the diagnosis of AD conforming to criteria proposed by NINCDS‐ADRDA (2011), followed‐up at a public university hospital, had their vitamin B12 levels assessed and MMSE scores evaluated.Result91 patients (88,35%) presented vitamin B12 normal range (200 – 800 pg/mL) and 12 patients (11,65%) presented vitamin B12 deficiency (≤ 200 pg/mL). From the normal range group, 13 patients (14,29%) presented severe cognitive impairment (MMSE < 10), 33 patients (36,26%) presented moderate cognitive impairment (MMSE = 10 – 20) and 45 patients (49,45%) presented mild cognitive impairment (MMSE > 20). From the deficiency group, 2 patients (16,8%) presented severe cognitive impairment, 5 patients (41,6%) presented moderate cognitive impairment and 5 patients (41,6%) presented mild cognitive impairment. Both groups, vitamin B12 normal range and deficiency, had on average the same educational level: 2,91 and 3,42 years, respectively.ConclusionIn this sample of patients with AD, B12 hypovitaminosis is associated with lower MMSE scores when compared to vitamin B12 normal range.