Associations between Homocysteine, Folic Acid, Vitamin B12 and Alzheimer's Disease: Insights from Meta-Analyses

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#age-factors #alzheimer-disease #databases-bibliographic #female #folic-acid

Associations between Homocysteine, Folic Acid, Vitamin B12 and Alzheimer's Disease: Insights from Meta-Analyses

Shen et al., 2015 | J Alzheimers Dis | Meta Analysis

Citation

Shen Liang, Ji Hong-Fang. Associations between Homocysteine, Folic Acid, Vitamin B12 and Alzheimer's Disease: Insights from Meta-Analyses. J Alzheimers Dis. 2015;46(3):777-90. doi:10.3233/JAD-150140

Abstract

The associations between homocysteine (Hcy), folic acid, and vitamin B12 and Alzheimer's disease (AD) have gained much interest, while remaining controversial. We aim to perform meta-analyses to evaluate comprehensively: i) Hcy, folic acid, and vitamin B12 levels in AD patients in comparison with controls; and ii) the association between Hcy, folic acid, and vitamin B12 levels and risk of AD. A literature search was performed using Medline and Scopus databases. A total of 68 studies were identified and included in the meta-analyses. Stata 12.0 statistical software was used to perform the meta-analyses. First, AD patients may have higher level of Hcy, and lower levels of folate and vitamin B12 in plasma than controls. Further age-subgroup analysis showed no age effect for Hcy levels in plasma between AD patients and matched controls, while the differences in folate and vitamin B12 levels further enlarged with increased age. Second, data suggests that high Hcy and low folate levels may correlate with increased risk of AD occurrence. The comprehensive meta-analyses not only confirmed higher Hcy, lower folic acid, and vitamin B12 levels in AD patients than controls, but also implicated that high Hcy and low folic acid levels may be risk factors of AD. Further studies are encouraged to elucidate mechanisms linking these conditions.

Key Findings

Further studies are encouraged to elucidate mechanisms linking these conditions.

Outcomes Measured

  • Requires manual extraction

Population

Field Value
Population See abstract
Sample Size 68
Age Range See abstract
Condition See abstract

MeSH Terms

  • Age Factors
  • Alzheimer Disease
  • Databases, Bibliographic
  • Female
  • Folic Acid
  • Homocysteine
  • Humans
  • Male
  • Vitamin B 12

Evidence Classification

  • Level: Meta Analysis
  • Publication Types: Journal Article, Meta-Analysis, Research Support, Non-U.S. Gov't
  • Vertical: folate

Provenance

Source extracted via PubMed E-utilities API on 2026-04-09