A study to investigate the effect of vitamin B12 levels in type 2 diabetic patients on body mass and blood count at the Diabetes Control and Treatment Center in Al-Khums
Keywords:
Type II Diabetes Mellitus, Metformin, Body Mass Index (BMI), Vitamin B12 DeficiencyAbstract
Metformin is the most commonly prescribed oral anti-diabetic drug and the firstline treatment for Type II Diabetes Mellitus (T2DM). Despite its established efficacy, clinical evidence suggests a potential association between its long-term use and Vitamin B12 deficiency, a condition that may lead to severe neurological and hematological complications. Comparative cross-sectional study, conducted in Libya at the Diabetes Control and Treatment Center in Al-Khums city, aimed to investigate the prevalence of Vitamin B12 deficiency among diabetic patients, assess the relationship between vitamin levels and both the daily metformin dose and Body Mass Index (BMI), in addition to measuring patients' level of awareness regarding this clinical association. The study included a sample of 226 flow of participants divided into three groups (metformin group, insulin group, and a healthy control group). Data were collected using a structured questionnaire and laboratory tests during the period from June 1, 2024, to February 28, 2025. Statistical analysis revealed a statistically significant relationship between long-term metformin use and decreased Vitamin B12 levels (P < 0.05). Furthermore, an elevated BMI was found to be an independent risk factor that increases the severity of the deficiency. Regarding health awareness, the study revealed a substantial knowledge gap, as 83.2% of the participants were unaware of the association between metformin use and Vitamin B12 deficiency. The study concludes that metformin negatively impacts Vitamin B12 levels in a dose-dependent manner, and that obesity or high BMI exacerbate this effect. It strongly recommends the routine inclusion of Vitamin B12 screening in the follow-up protocols for T2DM patients treated with metformin, particularly those receiving high doses or with an elevated BMI, and emphasizes the administration of appropriate drug supplements and adherence to necessary dietary intake, alongside activating health education programs to bridge the existing awareness gap
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