Prevalence of vitamin B12 deficiency among individuals with type 2 diabetes mellitus in a South Indian rural community


  • Shailendra D. Department of Pharmacology, MediCiti Institute of Medical Sciences and SHARE India, Hyderabad, Telangana, India
  • Rizwan Kalani Department of Neurology, University of Washington School of Medicine, Seattle, Washington, USA
  • K. M. Venkat Narayan Emory Global Diabetes Research Center, Hubert Department of Global Health, Atlanta, GA, USA
  • Dorairaj Prabhakaran Public Health Foundation of India and Centre for Chronic Disease Control New Delhi, India
  • Nikhil Tandon Department of Endocrinology, All India Institute of Medical Sciences, New Delhi, India
  • Reddy P. S. SHARE India, Hyderabad and Department of Medicine, University of Pittsburgh, PA USA



Metformin, Oral B12 supplementation, Type 2 diabetes mellitus, Vitamin B12


Background: To estimate the prevalence of vitamin B12 deficiency in a rural south Indian community and to evaluate the association between metformin use and prevalent vitamin B12 deficiency in people with T2DM stratified by oral vitamin B12 supplementation.

Methods: Using a cross sectional study design, a random sample of people with T2DM (N=438) was recruited from a rural community. Vitamin B12 deficiency was defined as serum B12 ≤200pg/ml. Data on metformin dose, duration of use, oral vitamin B12 supplementation, and diet were collected. Laboratory measurements included complete blood count, tests for hepatic, renal, and thyroid function, as well as serum vitamin B12 levels and HbA1c.

Results: The prevalence of vitamin B12 deficiency in people with T2DM was 11.2% (95% Confidence Interval (CI) 8.2%-14.1%). The odds of vitamin B12 deficiency in patients receiving a metformin dose of 2 grams/day were 4 times higher compared to those receiving ≤1 gram/day, after adjusting for oral B12 supplementation (odds ratio 4.2;95% CI 1.5-11.8). The odds of vitamin B12 deficiency in those taking metformin and receiving oral vitamin B12 supplementation were lower compared to those on metformin and not receiving vitamin B12 supplementation (adjusted odds ratio 0.20; 95% CI 0.06-0.70).

Conclusions: Vitamin B12 deficiency affects 1 in 10 people with T2DM, is associated with higher dose metformin use, and oral vitamin B12 supplementation mitigates B12 deficiency in this group.


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How to Cite

D., S., Kalani, R., Narayan, K. M. V., Prabhakaran, D., Tandon, N., & P. S., R. (2018). Prevalence of vitamin B12 deficiency among individuals with type 2 diabetes mellitus in a South Indian rural community. International Journal of Basic & Clinical Pharmacology, 7(2), 309–314.



Original Research Articles