Evaluation of Serum B12 Levels among Patients with Type 2 Diabetes Mellitus


  • Nahrain Azarya Adam
  • Dhia Mustafa Sulaiman
  • Sherwan Ferman Salih




Homocysteine, Insulin resistance, Type2 diabetes mellitus, Vitamin B12


Background and objectives:  Vitamin B12 insufficiency is widespread among type 2 diabetic people. Advanced age of patients, malnutrition, and malabsorption are the causative factors. Vitamin B12 deficiency causes raised levels of homocysteine & estimation of homocysteine will represent the metabolic status of B12. The aim of this study was to assess the incidence of B12 in relation with homocysteine levels and Insulin resistance in patients with type 2 diabetes mellitus regardless type of treatment used in treating diabetes.

Materials and methods: This is a cross-sectional study at Dohuk Azadi teaching hospital (biochemistry department)/Dohuk city from (February 2022. - August 2022), offering questionnaire randomly we collected 138 subjects and biochemical tests include (B12 assay, fasting glucose, HbA1c, fasting insulin, homocysteine) with measuring of Body Mass Index. Exclusion criteria: Age < 18 years old, using vitamin B/multi vitamins, using non-steroidal anti-inflammatory drug, debilitating diseases, alcohol intake.

Results: the sample (138) was divided into 2 groups: Type 2 Diabetes Miletus (70) patients & apparently healthy subjects (68). The difference was significant in age (51.24±9.27 vs29.57±7.2 years, p<.05), B12 (252.05±83.7vs337.03±121.6 pg/ml, p<.01), Homocysteine (13.493±4.8 vs 10.041±2.2 ?mol/L, p<.01), insulin resistance (6.82±2.0 vs 1.47±0.56, p<.001). ), there was a significant negative correlation between serum B12 and age, BMI, insulin resistance and serum homocysteine p value <0.01.

Conclusion: Vitamin B12 deficiency is frequent in people with type 2 diabetes mellitus. Yearly screening for vitamin B12 deficit using serum homocysteine and supplement should be adopted among diabetes individuals with risk factors of vitamin B12 insufficiency.


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How to Cite

Adam, N. A. ., Sulaiman, . D. M. ., & Salih, S. F. . (2024). Evaluation of Serum B12 Levels among Patients with Type 2 Diabetes Mellitus. AMJ (Advanced Medical Journal) , 9(1), 10-18. https://doi.org/10.56056/amj.2024.232