Effects of Folic Acid and Vitamin B12 Supplementation on Cognitive Impairment and Inflammation in Patients with Alzheimer's Disease: A Randomized, Single-Blinded, Placebo-Controlled Trial

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#aged #alzheimer-disease #china #cognitive-dysfunction #cytokines

Effects of Folic Acid and Vitamin B12 Supplementation on Cognitive Impairment and Inflammation in Patients with Alzheimer's Disease: A Randomized, Single-Blinded, Placebo-Controlled Trial

Chen et al., 2021 | J Prev Alzheimers Dis | Rct

Citation

Chen H, Liu S, ... Huang G. Effects of Folic Acid and Vitamin B12 Supplementation on Cognitive Impairment and Inflammation in Patients with Alzheimer's Disease: A Randomized, Single-Blinded, Placebo-Controlled Trial. J Prev Alzheimers Dis. 2021;8(3):249-256. doi:10.14283/jpad.2021.22

Abstract

OBJECTIVES: To evaluate the combined action of folic acid and vitamin B12 supplementation on cognitive performance and inflammation in patients with Alzheimer's disease (AD). DESIGN: This was a randomized, single-blind, placebo-controlled trial. PARTICIPANTS: Patients (n=120) diagnosed clinically as probable AD and in stable condition from Tianjin Key Laboratory of Cerebrovascular and Neurodegenerative Diseases. MEASUREMENTS: Individuals were randomly divided into the intervention group (n=60, folic acid 1.2 mg/d + vitamin B12 50 μg/d) and the placebo group (n=60). Cognitive performance, blood folate, vitamin B12, one carbon cycle metabolite, and inflammatory cytokine levels were measured at baseline and after 6 months. The data were analyzed using linear mixed models for repeated measures. RESULTS: A total of 101 participants (51 in the intervention group and 50 in the placebo group) completed the trial. Folic acid plus vitamin B12 supplementation had a beneficial effect on the MoCA total scores (P=0.029), naming scores (P=0.013), orientation scores (P=0.004), and ADAS-Cog domain score of attention (P=0.008), as compared to those of the control subjects. Moreover, supplementation significantly increased plasma SAM (P<0.001) and SAM/SAH (P<0.001), and significantly decreased the levels of serum Hcy (P<0.001), plasma SAH (P<0.001), and serum TNFα (P<0.001) compared to in the control subjects. CONCLUSIONS: Folic acid and vitamin B12 supplementation showed a positive therapeutic effect in AD patients who were not on a folic acid-fortified diet. The findings of this study help to delineate nutrient intervention as far as public health management for the prevention of dementia is concerned.

Key Findings

A total of 101 participants (51 in the intervention group and 50 in the placebo group) completed the trial. Folic acid plus vitamin B12 supplementation had a beneficial effect on the MoCA total scores (P=0.029), naming scores (P=0.013), orientation scores (P=0.004), and ADAS-Cog domain score of attention (P=0.008), as compared to those of the control subjects. Moreover, supplementation significantly increased plasma SAM (P<0.001) and SAM/SAH (P<0.001), and significantly decreased the levels of s

Outcomes Measured

  • inflammatory markers

Population

Field Value
Population alzheimer
Sample Size 120
Age Range See abstract
Condition cognitive

MeSH Terms

  • Aged
  • Alzheimer Disease
  • China
  • Cognitive Dysfunction
  • Cytokines
  • Dietary Supplements
  • Female
  • Folic Acid
  • Humans
  • Inflammation
  • Male
  • Neuropsychological Tests
  • Single-Blind Method
  • Vitamin B 12

Evidence Classification

  • Level: Rct
  • Publication Types: Journal Article, Randomized Controlled Trial
  • Vertical: vitamin-b12-cognition

Provenance

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