Metformin related Vitamin B12 Deficiency: an important Comorbid Factor in Diabetic patients

Background: Metformin decreases vitamin B12 absorption by tying up free calcium required for absorption of the intrinsic factor-B12 complex. Aims: A cross sectional study was designed to find out the relationship of vitamin B12 deficiency with impaired blood glucose and dyslipidemia in diabetic patients taking metformin. Methods: Six month based (Jan 2010 to June 2010) cross-sectional study was carried out. 50 male diabetic patients visiting outdoor department of Sir Ganga Ram Hospital with age range 40-60 were included in the study. Their duration of diabetes was 3-8 years. Patients taking insulin, lipid lowering drug, history of ketosis, any infection, having nephropathy were excluded from the study. Their BMI and blood pressure was noted. Blood sugars and lipid profile were estimated by standard kits of Merck using Auto analyzer. Injection of vitamin B12 (500 mu gm) obtained from Hilton Pharma Private Limited Lahore was injected I/M after every 15 days. Baseline investigations were repeated at the end of one month. Results: Level of fasting blood sugar and postprandial sugar was significantly decreased (P< 0.001) after therapy of I/M injection of vitamin B12. Level of serum cholesterol, triglyceride and LDL-chol was also decreased after therapy of vitamin B12, but significant difference (P< 0.001) was only observed in case of serum cholesterol. Level of HDL-chol was significantly increased (P< 0.001) after vitamin B12 therapy. Conclusion: It is therefore concluded that that physician should consider viatamin B-12 deficiency during management of comorbidities of diabetes, especially dyslipidemia.