Objectives: The objectives of the present study were to assess frequency of vitamin B₁₂ deficiency in metformin treated diabetic patients and to evaluate various factors associated with B₁₂ deficiency.

Materials and Methods: This cross-sectional study involved 82 adult patients of type 2 diabetes treated with metformin for at least one year in a tertiary care government hospital. Absolute vitamin B₁₂ deficiency was defined as ≤ 203 pg/ml, values of 203 -298 pg/ml were considered as borderline deficiency and values above >298 pg/ml as normal.

Results: The mean age of study population was 60.23 ± 9.20 years. The mean daily dose of metformin was 984.7 ± 185.7 mg. About 41% patients received combination therapy with metformin and glimepiride. Multivitamin supplements were used by 37.8% patients. Absolute vitamin B₁₂ deficiency was found in 7.31% and combined absolute plus borderline deficiency was found 34.1% patients. Age, gender, duration of diabetes, duration of metformin therapy, total daily dose of metformin, HbA1c value, use of sulfonylurea and use of H₂ antihistaminics was not significantly associated with vitamin B₁₂ deficiency. Use of multivitamin led to significant decrease in frequency of vitamin B₁₂ deficiency (16.1% vs. 45.1%, p=0.007).

Conclusion: Substantial proportion of patients receiving long term metformin show biochemical deficiency of Vitamin B₁₂.Use of multivitamin significantly reduces likelihood of vitamin B₁₂ deficiency.

Keywords: metformin, vitamin B₁₂, risk factors.

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Pore Shraddha M.

Department of Pharmacology, Government Medical College, Miraj, Dist-Sangli, Maharashtra- 416410

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