Prevalence of vitamin B12 deficiency in patients of type 2 diabetes mellitus on metformin: a case control study from Pakistan.
BACKGROUND
Diabetes Mellitus is the most common endocrine disorder and metformin is the most commonly prescribed oral hypoglycemic agent. Metformin is well known to cause viamin B12 deficiency due to effect on calcium-dependent membrane action in the terminal ileum leading to malabsorption of vitamin B12. The purpose of this study is to determine prevalence and associations of Vitamin B12 deficiency in patients of type 2 diabetes mellitus treated with metformin.


METHODS
This case control study was carried out in department of medicine, Combined Military Hospital, Kharian from 1(st) Jan 2012 to 30 december 2012. We enrolled 114 outdoor patients of type 2 diabetes mellitus currently on metformin for atleast 12 months, by consecutive sampling, and 105 age and sex matched patients taken as control. Patients with vitamin B12 levels of less than 150 pg/ml were said to be B12 deficient. The results were analyzed on SPSS version 16.


RESULTS
Serum B12 levels were low in 35 patients (31%) on metformin as compared to only 9 patients (8.6%) among controls,(p value 0.002). Mean B12 levels were significantly low in metformin group 311 pg/ml (±194.4), p value 0.03. Dose of metformin had inverse correlation with B12 levels and the difference was statistically significant with p-value < 0.001.


CONCLUSIONS
Our study demonstrated significantly high prevalence of vitamin B12 deficiency in patients treated with metformin with significant effect of dose and duration of metformin use on B12 levels. Physicians must recognize this important fact and screen diabetics on metformin therapy for underlying B12 deficiency.
Combined Military hospital kharian, Pakistan.
Raheel
R
Iftikhar
Combined Military hospital kharian, Pakistan.
Sultan Mehmood
SM
Kamran
Combined Military hospital kharian, Pakistan.
Adnan
A
Qadir
Combined Military hospital kharian, Pakistan.
Zohaib
Z
Iqbal
Combined Military hospital kharian, Pakistan.
Hassan
H
bin Usman
D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D003924:Diabetes Mellitus, Type 2 / Q000150:complications* / Q000188:drug therapy* / Q000453:epidemiology*; D005260:Female; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use*; D008297:Male; D008687:Metformin / Q000627:therapeutic use*; D008875:Middle Aged; D010154:Pakistan / Q000453:epidemiology; D015995:Prevalence; D014806:Vitamin B 12 Deficiency / Q000150:complications* / Q000188:drug therapy / Q000453:epidemiology*
D007004:Hypoglycemic Agents; D008687:Metformin
Diabetes Mellitus; Metformin; Vitamin B12 deiciency