Occurrence of Cobalamin (B-12) Deficiency in Metformin using Type II Diabetes Mellitus Patients

Abstract

Objective: To observe the occurrence of cobalamin (B12) deficiency and neuropathy in type II diabetic patients using metformin.

Study Design: Prospective, cross-sectional study.

Site and Duration of Study: Department of General Medicine and Diabetic Clinic, Nishtar Hospital Multan, from June 10, 2017 to February 25, 2018.

Methodology: Ninety two patients underwent proper detailed clinical history and examination, after which weight, mean blood pressure, HbA1_c, hemoglobin, mean corpuscular volume, serum cobalamin levels, Toronto Neuropathy Score were entered on a preformed performa. Electro-chemi-luminescence was used measurement of cobalamin. Toronto Neuropathy Score was calculated from history, clinical and neurological examination. Independent t-test was applied on continuous data and chi-square test was applied on nominal data using SPSS v.23. Confidence interval was taken as 95%.

Results: Mean serum cobalamin (B12) levels were 373.13±166.78 pg/ml and 538.48±172.29 pg/ml in M-Group and N-Group, respectively, difference being statistically significant (p<0.001). In M-Group, cobalamin (B12) deficient patients were statistically more in number (p=0.006) and Toronto Neuropathy Score was statistically higher (p<0.001). Number of patients developing neuropathy was also statistically higher (p=0.002) in M-Group.

Conclusion: After performing this study, we concluded that there is a strong association of metformin use with cobalamin (B12) deficiency in type-II diabetes mellitus patients. This can also lead to de novo development of peripheral neuropathy or can profoundly worsen the pre-existing diabetic neuropathy.

Keywords: Cobalamin, Type II diabetes mellitus, neuropathy, metformin.