Trial reportNutrients2013
Metformin lowers serum cobalamin without changing other markers of cobalamin status: a study on women with polycystic ovary syndrome.
Trial report in Nutrients, 2013. The graph could read no effect estimate from its abstract, so it casts no vote on the map. It is linked to trial NCT02280057 (Randomized, Cross-over Trial With Metformin in Women With Polycystic Ovary Syndrome), which is not on this map. Cited by 13 papers, 1 of them a synthesis that pooled it.
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
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.
Randomized, Cross-over Trial With Metformin in Women With Polycystic Ovary Syndrome
Who cites it
13 citing papers in PubMed, 1 synthesis or guideline pooled it, 39 citations in OpenAlex.
- Pooled it
- Trial
- Effects of metformin versus placebo on vitamin B12 metabolism in non-diabetic breast cancer patients in CCTG MA.32.Breast cancer research and treatment · 2017Trial
- Long-term Metformin Use and Vitamin B12 Deficiency in the Diabetes Prevention Program Outcomes Study.The Journal of clinical endocrinology and metabolism · 2016Trial
- Identification of a genetic risk factor for metformin-induced vitamin BDiabetologia · 2026Article
- Article
- Is metformin a possible treatment for diabetic neuropathy?Journal of diabetes · 2022Review
- Association between metformin dose and vitamin B12 deficiency in patients with type 2 diabetes.Medicine · 2019Article
- Proton Pump Inhibitors, H2-Receptor Antagonists, Metformin, and Vitamin B-12 Deficiency: Clinical Implications.Advances in nutrition (Bethesda, Md.) · 2018Review
- The association of metformin use with vitamin B12 deficiency and peripheral neuropathy in Saudi individuals with type 2 diabetes mellitus.PloS one · 2018 · on this mapObservational
- Review
- Perspectives on Peripheral Neuropathy as a Consequence of Metformin-Induced Vitamin B12 Deficiency in T2DM.International journal of endocrinology · 2017Review
- Biomarkers and Algorithms for the Diagnosis of Vitamin B12 Deficiency.Frontiers in molecular biosciences · 2016Review
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
5 authors at 2 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Treatment with the anti-diabetic drug metformin is followed by a decline in plasma cobalamin, but it is unsettled whether this denotes an impaired cobalamin status. This study has explored changes in the markers of cobalamin status in women with Polycystic Ovary Syndrome treated with metformin (1.5-2.5 g per day) (n = 29) or placebo (n = 23) for six months. Serum samples were collected before and after two, four, and six months of treatment. We found serum cobalamin to decline and reach significant lower levels after six months of treatment (p = 0.003). Despite the decline in serum cobalamin, we observed no reductions in the physiological active part of cobalamin bound to transcobalamin (holotranscobalamin), or increase in the metabolic marker of cobalamin status, methylmalonic acid. Instead, the non-functional part of circulating cobalamin bound to haptocorrin declined (p = 0.0009). Our results have two implications: The data questions whether metformin treatment induces an impaired cobalamin status in PCOS patients, and further suggests that serum cobalamin is a futile marker for judging cobalamin status in metformin-treated patients.
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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.