Comparative Observational Study of Serum Vitamin B12 Levels in Newly Diagnosed Type 2 Diabetes Mellitus and Non-Diabetic Patients

Abstract

BACKGROUND:
 Methylcobalamin or Vitamin B12 is a coenzyme involved in the synthesis of methionine, pyrimidine and purine bases. Type 2 diabetes is associated with oxidative stress; Vitamin B12 deficiency in diabetic patients taking metformin has been linked with oxidative stress. Because of these associations, it is implied that Vitamin B12 deficiency must be considered a risk factor for complications related to diabetes. However, several studies also suggest that deficiency of Vitamin B12 starts from the early stages of Diabetes. It has also been suggested that Vitamin B12 supplementation may help in reducing the complications related to diabetes. Although, the use of prophylactic Vitamin B12 to reduce complications related to diabetes remains controversial.
 Objective: This study aimed to explore the clinical relevance of Vitamin B12 in newly diagnosed T2DM patients. This study measured Vitamin B12 levels in newly diagnosed patients with type 2 diabetes (T2DM) and explored the correlations between its serum levels and various metabolic parameters in T2DM.
 RESEARCH DESIGN AND METHODS
 This was a 1 year, single-center, prospective, comparative, observational study. To collect data on age, smoking history, alcohol consumption, physical activity status, family history of T2DM, and medications, all subjects completed a self-answered questionnaire. Plasma samples were used to assay the biochemical parameters such as FBS, PPBS, HbA1c, lipid profile, and serum Vitamin B12. The participants were divided into newly diagnosed T2DM patients (n = 300) and healthy control subjects (n = 300).
 RESULTS
 Serum Vitamin B12 was significantly lower in newly diagnosed T2DM patients than in healthy control subjects (362.07± 182.25 vs 559.23± 275.05 pg/mL; P < 0.001). Serum Vitamin B12 correlated negatively with FBS, PPBS, and HbA1c in newly diagnosed T2DM patients.
 CONCLUSION
 Serum Vitamin B12 levels are significantly decreased in newly diagnosed T2DM patients. Our results suggest that adding Vitamin B12 as a supplement in the early stages of T2DM may contribute to possible microvascular (neuropathy, retinopathy, nephropathy, etc. ) complications related to Type 2 Diabetes Mellitus.