Evaluation of the effects of diabetes mellitus and metformin usage on serum vitamin B12 levels in cobalamin deficient subjects

Year 2019, Volume: 1 Issue: 1, 15 - 20, 29.10.2019

Duygu Nurdan Avcı , Canan Ersoy

https://doi.org/10.46310/tjim.631821

Abstract

Abstract: 

Introduction:Although there are studies evaluating vitamin B12 levels in different patient groups, there is none encountered in Turkish adult patients with or without DM reported in the English literature.The aim of the study was to evaluate the possible additional effects of diabetes and metformin usage on serum levels of vitamin B12 in cobalamin deficient Turkish adult patients. 

Material and Methods:Medical records of subjects ≥18 years of age, having a vitamin B12 level <180 pg/mL were screened, consecutive 98 subjects were included in the study. 

Results:Among a total of 75 female and 23 male subjects with a mean age of 51.3±15.9 years and vitamin B12 level of 139.3±29.2 pg/mL, 34 had the diagnosis of type 2 diabetes mellitus and 64 had no diabetes diagnosis. Mean ages were 59.0±10.8 years for diabetics and 47.2±16.8 years for nondiabetics. Vitamin B12 levels were found to be insignificantly low in people with the diagnosis of diabetes compared to without diabetes (131.2±30.6 and 143.5±27.7 pg/mL, respectively, p=0.05). Vitamin B12 levels had no correlation with diabetes duration, presence of complications, metformin usage duration. 

Conclusions:In conclusion, our results demonstrated that people with diabetes had lower levels of vitamin B12 compared to nondiabetics but this fact could not solely be explained by the duration of disease, accompanying complications, metformin treatment duration. All patients with or without the diagnosis of diabetes should be encouraged for sufficient vitamin B12 intake and all possible factors that lead to deficiency should be eliminated.

Keywords

vitamin B12 deficiency, metformin, diabetes mellitus

References

• Damião CP, Rodrigues AO, Pinheiro MF, Cruz RA Filho, Cardoso GP, Taboada GF, Lima GA. Prevalence of vitamin B12 deficiency in type 2 diabetic patients using metformin: a cross-sectional study. Sao Paulo Med J. 2016 Nov-Dec;134(6):473-9. doi: 10.1590/1516-3180.2015.01382111.
• Green R, Kinsella LJ. Current concepts in the diagnosis of cobalamin deficiency. Neurology. 1995 Aug;45(8):1435-40.
• Mazokopakis EE, Starakis IK. Recommendations for diagnosis and management of metformin-induced vitamin B12 (Cbl) deficiency. Diabetes Res Clin Pract. 2012 Sep;97(3):359-67. doi: 10.1016/j.diabres.2012.06.001.
• Dharmarajan TS, Norkus EP. Approaches to vitamin B12 deficiency. Early treatment may prevent devastating complications. Postgrad Med. 2001 Jul;110(1):99-105.
• Langan RC, Zawistoski KJ. Update on vitamin B12 deficiency. Am Fam Physician. 2011 Jun 15;83(12):1425-30.
• American Diabetes Association. 2. Classification and Diagnosis of Diabetes: Standards of Medical Care in Diabetes-2018. Diabetes Care. 2018 Jan;41(Suppl 1):S13-S27. doi: 10.2337/dc18-S002.
• Ahmed MA, Muntingh G, Rheeder P. Vitamin B12 deficiency in metformin-treated type-2 diabetes patients, prevalence and association with peripheral neuropathy. BMC Pharmacol Toxicol. 2016 Oct 7;17(1):44.
• American Diabetes Association. Standards of Medical Care in Diabetes-2016 Abridged for Primary Care Providers. Clin Diabetes. 2016 Jan;34(1):3-21. doi: 10.2337/diaclin.34.1.3.
• Reinstatler L, Qi YP, Williamson RS, Garn JV, Oakley GP Jr. Association of biochemical B₁₂ deficiency with metformin therapy and vitamin B₁₂ supplements: the National Health and Nutrition Examination Survey, 1999-2006. Diabetes Care. 2012 Feb;35(2):327-33. doi: 10.2337/dc11-1582.
• Ko SH, Ko SH, Ahn YB, Song KH, Han KD, Park YM, Ko SH, Kim HS. Association of vitamin B12 deficiency and metformin use in patients with type 2 diabetes. J Korean Med Sci. 2014 Jul;29(7):965-72. doi: 10.3346/jkms.2014.29.7.965.
• Akinlade KS, Agbebaku SO, Rahamon SK, Balogun WO. Vitamin B12 levels in patients with type 2 diabetes mellitus on metformin. Ann Ib Postgrad Med. 2015 Dec;13(2):79-83.
• Leung S, Mattman A, Snyder F, Kassam R, Meneilly G, Nexo E. Metformin induces reductions in plasma cobalamin and haptocorrin bound cobalamin levels in elderly diabetic patients. Clin Biochem. 2010 Jun;43(9):759-60. doi: 10.1016/j.clinbiochem.2010.02.011.
• Andrès E, Loukili NH, Noel E, Kaltenbach G, Abdelgheni MB, Perrin AE, Noblet-Dick M, Maloisel F, Schlienger JL, Blicklé JF. Vitamin B12 (cobalamin) deficiency in elderly patients. CMAJ. 2004 Aug 3;171(3):251-9.
• Lindenbaum J, Rosenberg IH, Wilson PW, Stabler SP, Allen RH. Prevalence of cobalamin deficiency in the Framingham elderly population. Am J Clin Nutr. 1994 Jul;60(1):2-11.
• Snow CF. Laboratory diagnosis of vitamin B12 and folate deficiency: a guide for the primary care physician. Arch Intern Med. 1999 Jun 28;159(12):1289-98.
• Türkiye Endokrinoloji ve Metabolizma Derneği. Obezite Tanı ve Tedavi Kılavuzu 2019. 12. baskı. Ankara: Miki Matbaacılık; 2019: 1-268.
• Calvo Romero JM, Ramiro Lozano JM. Vitamin B(12) in type 2 diabetic patients treated with metformin. Endocrinol Nutr. 2012 Oct;59(8):487-90. doi: 10.1016/j.endonu.2012.06.005.