Vitamin B12 deficiency in turkish patients with Type 2 Diabetes Mellitus

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İsmail Gökhan Kalaycı
Savaş Karataş
Burcu Hacıoğlu


Objective: Type 2 diabetes (T2DM) disease and related changes in blood parameters bring essential health risks. This study was carried out to determine the frequency of vitamin B12 deficiency in T2DM patients, the effect of B12 deficiency on blood glucose, HbA1c control and lipid parameters, and the B12 level in diabetes patients using metformin.

Material and Methods: 287 patients with T2DM who were followed up in the Endocrinology department of Istanbul Training and Research Hospital were evaluated. After the patients called for control had fasted for 8 hours, blood tests were performed, and biochemical parameters were determined with standard laboratory techniques. Vitamin B12 <180 mg/dl was accepted as a deficiency, and patients were divided into groups regarding vitamin B12 deficiency. The chemiluminescence method was used to determine serum Vitamin B12 levels. Data were analyzed using SPSS version 22.0 (IBM Corporation, Armonk, NY, USA).

Results: A total of 287 T2DM patients were included in the study. B12 deficiency is present in 29.8% of T2DM patients. Vitamin B12 values were found to be lower in patients with T2DM using metformin (280.2 pg /ml ±151.06 pg/ml, p<0.05); however, lower vitamin B12 values did not have a significant effect on blood sugar control (p=0,3), and hypovitaminosis Vitamin B12 was associated with elevated hypertriglyceridemia (p=0,03).

Conclusion: According to the current study, serum vitamin B12 level was not associated with blood glucose and HbA1c; a relationship was found between vitamin B12 deficiency and higher hypertriglyceridemia. A significant proportion of T2DM patients using metformin had lower levels of vitamin B12 compared to T2DM patients not using metformin. Vitamin B12 levels should be monitored regularly in the follow-up of patients with T2DM using metformin.


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How to Cite
Kalaycı, İsmail G., Karataş, S., & Hacıoğlu, B. (2023). Vitamin B12 deficiency in turkish patients with Type 2 Diabetes Mellitus. Medical Science and Discovery, 10(5), 291–294.
Research Article
Author Biography

İsmail Gökhan Kalaycı, University of Health Sciences Istanbul Training And Research Hospital, Dept of Family Medicine, İstanbul, TR



Received 2023-04-08
Accepted 2023-05-02
Published 2023-05-11


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