ArticleJournal of Alzheimer's disease : JAD2021
Plasma Vitamin B12 Levels, High-Dose Vitamin B12 Treatment, and Risk of Dementia.
Article in Journal of Alzheimer's disease : JAD, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 4 papers.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
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Who cites it
4 citing papers in PubMed, 14 citations in OpenAlex.
- Association of low vitamin B12 status with incident dementia and stroke: an EHR database study.Frontiers in nutrition · 2026Article
- Higher vitamin BAlzheimer's & dementia : the journal of the Alzheimer's Association · 2025Article
- One-Carbon Metabolism Biomarkers and Risks of Incident Neurocognitive Disorder among Cognitively Normal Older Adults.Nutrients · 2022Article
- Nutrition, Physical Activity, and Other Lifestyle Factors in the Prevention of Cognitive Decline and Dementia.Nutrients · 2021Review
Corrections and comments
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Authors and funding
7 authors at 1 institution in 2 countries.
Funding
Abstract
backgroundIt is controversial whether B12 deficiency causes dementia or B12 treatment can prevent dementia.
objectiveTo assess associations between low plasma (P-)B12 levels, B12 treatment, and risk of Alzheimer's disease (AD; primary outcome) and all-cause or vascular dementia (secondary outcomes).
methodsWe conducted a population-based cohort study using Danish registry data to assess associations between low P-B12 levels, high-dose injection or oral B12 treatment, and risk of dementia (study period 2000-2013). The primary P-B12 cohort included patients with a first-time P-B12 measurement whose subsequent B12 treatment was recorded. The secondary B12 treatment cohort included patients with a first-time B12 prescription and P-B12 measurement within one year before this prescription. For both cohorts, patients with low P-B12 levels (<200 pmol/L) were propensity score-matched 1:1 with patients with normal levels (200-600 pmol/L). We used multivariable Cox regression to compute 0-15-year hazard ratios for dementia.
resultsFor low P-B12 and normal P-B12 level groups, we included 53,089 patients in the primary P-B12 cohort and 13,656 patients in the secondary B12 treatment cohort. In the P-B12 cohort, hazard ratios for AD centered around one, regardless of follow-up period or treatment during follow-up. In the B12 treatment cohort, risk of AD was unaffected by low pre-treatment P-B12 levels, follow-up period and type of B12 treatment. Findings were similar for all-cause and vascular dementia.
conclusionWe found no associatio1n between low P-B12 levels and dementia. Associations were unaffected by B12 treatment. Results do not support routine screening for B12 deficiency in patients with suspected dementia.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.