ArticleJournal of the American Geriatrics Society2017
Long-term Metformin Therapy and Monitoring for Vitamin B12 Deficiency Among Older Veterans.
Article in Journal of the American Geriatrics Society, 2017. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 15 papers, 1 of them a synthesis that pooled it.
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Who cites it
15 citing papers in PubMed, 1 synthesis or guideline pooled it, 50 citations in OpenAlex.
- Diabetes Treatment in the Elderly: Incorporating Geriatrics, Technology, and Functional Medicine.Current diabetes reports · 2018Pooled it
- Antihyperglycemic and Antioxidative Stress Effects ofFood science & nutrition · 2025Article
- A Framework to Guide Defining an Upper Threshold of Crystalline Vitamin B12 in Foods and Food Supplements.Current nutrition reports · 2025Review
- Vitamin BIrish journal of medical science · 2024Review
- Diagnosis, Treatment and Long-Term Management of Vitamin B12 Deficiency in Adults: A Delphi Expert Consensus.Journal of clinical medicine · 2024Article
- Evaluating Physician Knowledge, Attitudes, and Practices in Screening and Supplementation for Vitamin B12 Deficiency in Type 2 Diabetes Patients Treated with Metformin.Diabetes, metabolic syndrome and obesity : targets and therapy · 2024Article
- Synthesis, Quality Control and Preliminary Activity Evaluation of a New Compound HM475.Molecules (Basel, Switzerland) · 2023Article
- Review
- Long-term metformin therapy and vitamin B12 deficiency: An association to bear in mind.World journal of diabetes · 2021Review
- Long-term metformin treatment and risk of peripheral neuropathy in older Veterans.Diabetes research and clinical practice · 2020Article
- Vitamin B12 deficiency and the knowledge and practice of physicians regarding screening for vitamin B12 deficiency among type 2 diabetic patients on metformin in selected hospitals in Riyadh, Saudi Arabia.Journal of family medicine and primary care · 2019Article
- Healthy ageing: the natural consequences of good nutrition-a conference report.European journal of nutrition · 2018Article
- B Vitamin Complex and Chemotherapy-Induced Peripheral Neuropathy.Current oncology reports · 2017Review
- Vitamin BBiomolecules · 2017Review
- Evaluation of vitamin B12 monitoring in patients on metformin in urban ambulatory care settings.Pharmacy practiceArticle
Corrections and comments
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Authors and funding
9 authors at 3 institutions in 1 country.
Funding
Abstract
objectiveTo examine the association between long-term metformin therapy and serum vitamin B12 monitoring.
designRetrospective cohort study.
settingA single Veterans Affairs Medical Center (VAMC), 2002-2012.
participantsVeterans 50 years or older with either type 2 diabetes and long-term metformin therapy (n = 3,687) or without diabetes and no prescription for metformin (n = 13,258). MEASUREMENTS: We determined diabetes status from outpatient visits, and defined long-term metformin therapy as a prescription ≥500 mg/d for at least six consecutive months. We estimated the proportion of participants who received a serum B12 test and used multivariable logistic regression, stratified by age, to evaluate the association between metformin use and serum B12 testing.
resultsOnly 37% of older adults with diabetes receiving metformin were tested for vitamin B12 status after long-term metformin prescription. The mean B12 concentration was significantly lower in the metformin-exposed group (439.2 pg/dL) compared to those without diabetes (522.4 pg/dL) (P = .0015). About 7% of persons with diabetes receiving metformin were vitamin B12 deficient (<170 pg/dL) compared to 3% of persons without diabetes or metformin use (P = .0001). Depending on their age, metformin users were two to three times more likely not to receive vitamin B12 testing compared to those without metformin exposure, after adjusting for sex, race and ethnicity, body mass index, and number of years treated at the VAMC.
conclusionLong-term metformin therapy is significantly associated with lower serum vitamin B12 concentration, yet those at risk are often not monitored for B12 deficiency. Because metformin is first line therapy for type 2 diabetes, clinical decision support should be considered to promote serum B12 monitoring among long-term metformin users for timely identification of the potential need for B12 replacement.
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