Assessment of Serum Vitamin B12 and Folate Levels and Macrocytosis in Patients with Type 2 Diabetes Mellitus on Metformin Attending Tikur Anbessa Specialized Hospital, Addis Ababa, Ethiopia: A Cross-Sectional Study

Wondwossen Wale Tesega, 1 Solomon Genet, 2 Gnanasekaran Natesan, 2 Getahun Tarekegn, 2 Fitsum Girma, 3 Dinkinesh Chalchisa, 3 Yohannes Belay, 3 Zeleke Geto, 4 Tadesse Asmamaw Dejenie 5 1Department of Biomedical Sciences, School of Medicine, College of Health Sciences, Arbaminch University, Arba Minch, Ethiopia; 2Department of Medical Biochemistry, School of Medicine, College of Health Sciences, Addis Ababa University, Addis Ababa, Ethiopia; 3National Reference Laboratory for Immunohematology, Ethiopian Public Health Institute, Addis Ababa, Ethiopia; 4Department of Biomedical Science, College of Medicine and Health Science, Wollo University, Dessie, Ethiopia; 5Department of Biochemistry, School of Medicine, College of Medicine and Health Science, University of Gondar, Gondar, EthiopiaCorrespondence: Tadesse Asmamaw Dejenie Tel +251 90-904-5760Email as24tadesse@gmail.comBackground: Metformin is the first-line drug in the treatment of type 2 diabetes mellitus. Monitoring vitamin B 12 deficiency associated with long-term and high-dose therapy is not a common practice in many clinical settings in Ethiopia.Objective: The study aimed to measure levels of serum vitamin B 12 and folate and to assess the macrocytic status of type 2 diabetes mellitus patients on metformin.Methods: A cross-sectional study was conducted on 80 type 2 diabetes mellitus patients who had been on metformin for 5 months or more at the diabetic clinic of Tikur Anbessa Specialized Teaching Hospital. Serum vitamin B 12 and folate levels were quantified by chemiluminescent immunoassays. Mean corpuscular volume was determined by complete blood count. Differences in vitamin B 12 and folate levels and mean corpuscular volume between different groups were assessed using Kruskal–Wallis H and Mann–Whitney U tests.Results: Vitamin B 12 and folate deficiency were documented in 5% and 23.8% of participants, respectively, and 6.2% of patients were macrocytic. Levels of vitamin B 12 and