Frequency of Vitamin B12 deficiency in patients with type 2 diabetes mellitus taking metformin

Aim: to determine the frequency of vitamin b12 deficiency in patients with type 2 diabetes mellitus taking metformin. place & duration of study: the study was conducted from 1 oct 2013 to 31 mar 2014 at department of medicine combined military hospital (cmh) multan methods: a total of 135 cases with type 2 diabetes mellitus,aged 40 or more,taking metformin for at least one year presenting to medical opd were included in the study. results: mean age as 54.53+8.56 years,75(54.7%) were male and 62(45.3%) were females. hba1c of patients were between 6.6 and 12.1% with a mean of 8.5% and standard deviation of 0.87. mean fasting plasma glucose was calculated to be 208+46.3mg/dl,the duration of metformin use was between 1.5 years and 8.4 years with a mean of 5.1+1.9 years. the mean dose of metformin was calculated to be 1970 mg/day with a standard deviation of 727.0 mean vitamin b12 levels among 137 patients taking metformin were found to be 311.6pmol/l. the standard deviation was 141.5. serum vitamin b12 levels were found to be deficient (<150 pmol/l) in 19 patients (13.9%). conclusion: we concluded that a considerable percentage of diabetic patients treated with metformin have low vitamin b12 levels. so,physicians must recognize this important association of metformin with b12 deficiency.