DOI: http://dx.doi.org/10.18203/2319-2003.ijbcp20205128

Prevalence of vitamin B12 deficiency in type 2 diabetes mellitus patients on metformin therapy in a tertiary care hospital

Gomathi A., Keerthiga K.

Abstract


Background: The objective of the study was to estimate the prevalence of vitamin B12 deficiency and presence of peripheral neuropathy in type 2 diabetes patients on metformin treatment.

Methods: This cross-sectional study was carried out in Department of Biochemistry and Medicine in a tertiary care teaching hospital in south India. Type 2 diabetes mellitus patients diagnosed based on World Health Organization (WHO) criteria treated with metformin for more than 6 months were included in the study. B12 levels were estimated and DNS scoring, vibration perception test and 10 gm Semmes-Weinstein monofilament test done.

Results: A total of 55 participants were identified. Most of them were on 1500 mg of metformin once a day in divided dose. In this study maximum number of participants are in the age group of 50-70 years. Peripheral neuropathy is seen in 43.9% of persons with normal B12 levels and 28.5% of persons with low B12 levels. A Chi square test showed a chi square statistic value of 1.8221 with a p value of 0.312 which is not significant. Univariate analysis showed vitamin B12 deficient patients are of significantly higher age (63 years versus 57 years p=0.01) and with higher duration of treatment (9 years versus 6 years p=0.01).

Conclusions: Prolonged metformin therapy is associated with deficiency of vitamin B12. The prevalence of B12 deficiency among diabetic patients on metformin was found to be 25.45%. Routine B12 estimation and correction of low B12 levels will be beneficial to these patients. Earlier initiation of B12 in patients on metformin may prevent the onset of neurological damage.


Keywords


Metformin, B12 deficiency, Diabetes mellitus

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