Association Between Homocysteine and Vitamin Levels in Demented Patients

J Alzheimers Dis. 2021;81(4):1781-1792. doi: 10.3233/JAD-201481.

Abstract

Background: Although it is known that the nutritional status among elderly persons and, in particular, patients with dementia, is compromised, malnutrition that results in insufficient uptake of several vitamins is often not diagnosed.

Objective: An elevated homocysteine level is a known strong risk factor for vascular dementia (VaD) and Alzheimer's disease (AD). Several B vitamins are involved in the metabolism of homocysteine. Therefore, we investigated the serum levels of vitamin B1, vitamin B6, folate, and vitamin B12 in 97 patients with mild cognitive impairment (MCI) or different forms of dementia and 54 elderly control persons without dementia.

Results: Compared to aged non-demented people, vitamins B1, B6, B12, and folate were decreased in serum of patients with AD, and patients with Lewy body dementia had reduced vitamin B12 level. Vitamin B6 was diminished in VaD. Patients with frontotemporal dementia showed no alterations in vitamin levels. Age was identified as an important factor contributing to the concentrations of vitamin B1 and B6 in serum, but not vitamin B12 and folate. Increased levels of total homocysteine were detected especially in MCI and AD. Homocysteine correlated negatively with levels of vitamins B6, B12, and folate and positively with Q Albumin.

Conclusion: Our data suggest that despite increased homocysteine already present in MCI, vitamin levels are decreased only in dementia. We propose to determine the vitamin levels in patients with cognitive decline, but also elderly people in general, and recommend supplementing these nutrients if needed.

Keywords: B vitamins; dementia; homocysteine.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Dementia / blood*
  • Female
  • Folic Acid / blood*
  • Homocysteine / blood*
  • Humans
  • Male
  • Middle Aged
  • Thiamine / blood*
  • Vitamin B 12 / blood*
  • Vitamin B 6 / blood*

Substances

  • Homocysteine
  • Vitamin B 6
  • Folic Acid
  • Vitamin B 12
  • Thiamine