Prevalence of vitamin B12 deficiency and its association with metformin-treated type 2 diabetic patients: A cross sectional study

Abstract

Metformin is the most-used drug in type 2 diabetes mellitus (T2DM) management, but it may lower B 12 status as a use consequence. However, few studies in Saudi Arabia have assessed this risk. This study aimed to estimate the prevalence of vitamin B 12 deficiency in metformin-treated type 2 diabetic patients and its association with drug duration and dose with relation to B 12 dietary intake. A cross sectional study was conducted with 206 patients with type 2 diabetic patients using metformin for 6 months or more and attending the diabetic clinics at Al-Noor Specialist Hospital in Holy Makkah. Serum B 12 levels were estimated, and biochemical B 12 deficiency was defined as serum levels <243 nmol/L. Demographic, medical history, dietary assessment for B 12 intake, and data on metformin use were collected using an online survey. Statistical package for the social sciences (SPSS) version 25 was used for statistical analysis. Vitamin B 12 deficiency occurred in 17.5% of the patients using metformin. Significant differences existed according to diabetes duration ( p = 0.002) between patients showing deficiencies and normal ranges of vitamin B 12 . No significant differences were found according to metformin dose, duration, and vitamin B 12 intake. The prevalence of B 12 deficiency in patients with type 2 diabetic patients using metformin was 17.5%. The risk of this relationship might increase with longer metformin use and is influenced by the occurrence and duration of diabetes .