Association of Vitamin B12 deficiency & clinical Neuropathy with metformin use in type 2 Diabetes patients

SHAREEF, SHAHAD AKRAM; ABDULGHANI, ZAINAB ABDULRAZAQ

doi:10.52573/ipmj.2025.163231

	Association of Vitamin B12 deficiency & clinical Neuropathy with metformin use in type 2 Diabetes patients
Iraqi Postgraduate Medical Journal
Volume 25, Issue 2, April 2026, Pages 210-218 PDF (3.8 M)
Document Type: Research Paper
DOI: 10.52573/ipmj.2025.163231
Authors
SHAHAD AKRAM SHAREEF^* ¹; ZAINAB ABDULRAZAQ ABDULGHANI²
¹Baghdad- Al-Karkh Health Directorate, Baghdad, Iraq.
²Medical College, university of Baghdad, Baghdad, Iraq.
Abstract
Background: Type II diabetes mellitus (T2DM) is associated with long-term microvascular complications such as neuropathy, nephropathy, and retinopathy. Diabetic peripheral neuropathy (DPN), affecting nearly 50% of patients, poses a risk for severe outcomes like foot ulcers and amputations. Vitamin B12 deficiency can further exacerbate neurological issues through axonal demyelination, potentially leading to irreversible nerve damage. Method: this cross-sectional observational study was conducted at the Iraqi National Center for Diabetes & Endocrinology to assess serum vitamin B12 levels in T2DM patients on metformin versus other oral hypoglycemic agents, and to explore the association with peripheral neuropathy. Results: A total of 89 patients (44 males and 45 females, mean age 56 years) were enrolled, including 63 on metformin and 26 on alternative therapies. Fasting blood samples were collected for vitamin B12, glucose, and HbA1c levels. The mean serum B12 level was significantly lower in metformin users (P < 0.01), although there were no significant differences in BMI, FBS, or HbA1c. Metformin users had a longer duration of diabetes by an average of 2.6 years (P < 0.01). Most metformin users (92.06%) were taking 1000–2000 mg daily. Overall, vitamin B12 deficiency was found in 7.8% of the cohort, with higher prevalence in metformin users compared to non-users (9.5% vs. 3.8%, P < 0.036). Although metformin was associated with a higher incidence of mild to moderate peripheral neuropathy, no significant relationship was found between B12 deficiency and neuropathy. Conclusion: The study concludes that metformin use is significantly associated with vitamin B12 deficiency in T2DM patients.
Keywords
Vitamin B12; deficiency; clinical Neuropathy; metformin; type 2 Diabetes

Statistics Article View: 202 PDF Download: 107