The Prevalence of Vitamin B12 Deficiency in Patients with Type2 Diabetes Mellitus on Metformin

The study included 184 patients with type 2 diabetes referred to the specialist clinic or admitted in the sections of Al-Assad University Hospital in Damascus during the years 2012-2013. The patients were divided into three groups: Group A: a group of patients with diabetes is not treated with Metformin, 72 patients (39,1%). Group B: a group of patients with diabetes is treated with Metformin for more than 18 months, 72 patients (39,1%). Group C: a group of patients with diabetes is treated with Metformin for less than 6 months, 40 patients (21,8%). This study showed that 43,5% of the patients have Vit B12 deficiency: 32,6% of patients with diabetes treated with Metformin compared with 10,9% non treated with Metformin. The patients who were treated with Metformin (112 patients) were divided by dose intake and then depending on the duration of treatment into two groups for each category and shown an inverse correlation between duration and dose of therapy with metformin and levels of Vit B12. We also found that despite the increased risk of Vit B12 deficiency in patients with diabetes treated with Metformin but this was not associated with the occurrence of symptoms such as megaloplastic anemia and neurological symptoms.