Background and Aim: The association between Vitamin B12 deficiency and metformin use among Type 2 diabetic patients (T2DM) were reported. We wanted to determine the prevalence of Vitamin B12 deficiency among T2DM patients who were on metformin seen in our institution.

Methods: We conducted a retrospective medical records review of Saudi patients diagnosed with Type 2 Diabetes Mellitus patient aged between 30-50 years who visited the Primary Care Center of Security Forces Hospital in Riyadh, Saudi Arabia during the last two years 2018-2019.

Results: A total of 289 T2DM patients, 161 (55.7%) males and 128 (44.3%) females with a mean age of 44.66 ± 4.49 years were included in the study. The mean Vitamin B12 level was 296.68 ± 114.79 pg/mL. There were 12 patients (4.2%) with Vitamin B12 deficiency, and the remaining 277 patients (95.8%) had normal Vitamin B12 level. The mean (SD) Vitamin B12 level of males was significantly higher among males than females (311.75 ± 115.34 pg/mL versus 277.72 ± 111.68 pg/mL, p=0.012). There was no significant difference in the mean (SD) Vitamin B12 level among patients <50 years old and patients ≥50 years old (292.40 ± 111.82 pg/mL versus 324.08 ± 130.52 pg/mL, p=0.109). 

Conclusion: In summary, we found 19.72% prevalence of Vitamin B12 deficiency among patients seen at the family medicine clinics with 40.14% of our patients in the borderline Vitamin B12 status. Contrary to other previous studies, we found that females are more at risk for Vitamin B12 deficiency in this region. This study suggests the importance of measuring the Vitamin B12 levels of women especially and improve their Vitamin B12 status.

Keywords: Vitamin B12 deficiency, Type 2 diabetes, Metformin, prevalence, Saudi Arabia.

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Dr Abdulkareem Alanazi

Family Physician, Ministry of Health, Riyadh, KSA