SynthesisEuropean journal of clinical nutrition2018
Associations of genetic determinants of serum vitamin B12 and folate concentrations with hay fever and asthma: a Mendelian randomization meta-analysis.
Synthesis in European journal of clinical nutrition, 2018. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 9 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.
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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.
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Who cites it
9 citing papers in PubMed, 15 citations in OpenAlex.
- Micronutrients in Pediatric Asthma: Biological Mechanisms and Clinical Evidence-A Narrative Review.Nutrients · 2026Review
- Dietary patterns and micronutrients in respiratory infections including COVID-19: a narrative review.BMC public health · 2024Review
- The Role of Vitamins in the Pathogenesis of Asthma.International journal of molecular sciences · 2023Review
- Article
- Causal risk factors for asthma in Mendelian randomization studies: A systematic review and meta-analysis.Clinical and translational allergy · 2022Review
- Smoking behavior might affect allergic rhinitis and vasomotor rhinitis differently: A mendelian randomization appraisal.The World Allergy Organization journal · 2022Article
- Dietary Intake and Asthma in Preschoolers: A Logistic Lasso Regression Analysis.Frontiers in pediatrics · 2022Article
- Mineral Micronutrients in Asthma.Nutrients · 2021Review
- AllergoOncology: Microbiota in allergy and cancer-A European Academy for Allergy and Clinical Immunology position paper.Allergy · 2019Article
Corrections and comments
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Authors and funding
17 authors at 6 institutions in 3 countries.
Funding
Abstract
BACKGROUND/
objectivesStudies of the effect of vitamin B12 and folate on the risk of asthma and hay fever have shown inconsistent results that may be biased by reverse causation and confounding. We used a Mendelian randomization approach to examine a potential causal effect of vitamin B12 and folate on hay fever, asthma, and selected biomarkers of allergy by using 11 vitamin B12-associated single-nucleotide polymorphisms (SNPs) and 2 folate-associated SNPs as unconfounded markers. SUBJECTS/
methodsWe included 162,736 participants from 9 population-based studies including the UK Biobank. Results were combined in instrumental variable and meta-analyses and effects expressed as odds ratios (ORs) or estimates with 95% confidence interval (CI).
resultsUsing genetic proxies for B12 and folate, instrumental variable analyses did not show evidence for associations between serum B12 and hay fever: OR = 1.02 (95% CI: 0.98, 1.05), asthma: OR = 0.99 (95% CI: 0.95, 1.04), allergic sensitization: OR = 1.02 (95% CI: 0.74, 1.40), or change in serum IgE: 10.0% (95% CI: -9.6%, 29.6%) per 100 pg/ml B12. Similarly, there was no evidence for association between serum folate and hay fever: OR = 0.74 (95% CI: 0.45, 1.21), asthma: OR = 0.80 (95% CI: 0.43, 1.49), or allergic sensitization: OR = 1.92 (95% CI: 0.11, 33.45), but there was a statistically significant association with change in serum IgE: 2.0% (95% CI: 0.43%, 3.58%) per 0.1 ng/ml serum folate.
conclusionsOur results did not support the hypothesis that levels of vitamin B12 and folate are causally related to hay fever, asthma, or biomarkers of allergy, but we found evidence of a positive association between serum folate and serum total IgE.
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