ReviewSAGE open medicine2024
Association of vitamin B12, folate, and homocysteine with COVID-19 severity and mortality: A systematic review and meta-analysis.
Review in SAGE open medicine, 2024. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 5 papers, 2 of them syntheses that pooled it.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
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
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
5 citing papers in PubMed, 2 syntheses or guidelines pooled it.
- Vitamin B12, folate, and homocysteine levels in children and adolescents with obesity: a systematic review and meta-analysis.Frontiers in public health · 2025Pooled it
- Homocysteine, vitamin B12, and folate circulating levels in women with and without polycystic ovary syndrome: A systematic review and meta-analysis.Women's health (London, England)Pooled it
- Triglyceride-glucose index and lipid ratios in women with and without polycystic ovary syndrome: a systematic review and meta-analysis.Therapeutic advances in endocrinology and metabolism · 2025Article
- Charting the COVID-19 vaccination journey in Saudi Arabia: Insights into post-vaccination adverse effects and immunization dynamics.Frontiers in pharmacology · 2025Article
- Vitamin BFrontiers in nutrition · 2025Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
8 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Objective: We aimed to review the available evidence on the association between vitamin B12, folate, and homocysteine levels with worse outcomes among COVID-19 patients. Methods: The search was carried out in ten databases simultaneously run on 10 May 2023, without language restrictions. We included cross-sectional, case-control, and cohort studies. The random-effects meta-analysis was performed using the Sidik-Jonkman method and corrected 95% confidence intervals using the truncated Knapp-Hartung standard errors. Standardized mean difference and 95% CI was used as the measure effect size. Results: Thirteen articles were included in this review ( Conclusion: Elevated serum levels of vitamin B12 were associated with higher mortality in patients with COVID-19. Severe cases of COVID-19 were associated with low serum folate levels. Future studies should incorporate a larger sample size.
Indexed as
Identifiers
What OpenQuestion holds
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.