Assessment of the knowledge and practice of Jordanian family medicine practitioners regarding vitamin B12 screening for type 2 diabetes mellitus patients on metformin

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Maysaa Waddah Alwadi
Rawan Badaineh
Tareq Alwedyan
Esraa Gogazeh
Ola A. Badir


Type 2 Diabetes Mellitus, Metformin, Vitamin B12 deficiency, Family Physicians


Background: Metformin is one of the most important treatments for type 2 diabetes mellitus (T2DM) patients. Mostly metformin has a safe profile but in some cases, it may cause some serious long-term hematological and neurological side effects mainly due to vitamin B12 deficiency. It is proven that there is a strong association between B12 deficiency and hematological and neurological manifestations, especially for T2DM patients on metformin. Hence, the American Diabetic Association (ADA) recommends vitamin B12 screening for those on metformin for a long duration. Objectives: To evaluate the knowledge and practice of family physicians among diabetic patients on metformin, and to evaluate the factors that enhance and prevent vitamin B12 screening. Method: A validated questionnaire was designed and distributed online for family medicine practitioners between the period of in June and September 2022. 147 family physicians participated in the study. A scoring system was used to calculate the knowledge, practice, and total scores. Results: The results reveal a high total knowledge score among participants about vitamin B12 manifestations and screening in T2DM patients. However, only half of the participants follow the ADA recommendations routinely (53.06)%. The total practice score is low as most participants (87.7%) answer only 9 of 18 questions correctly. Moreover, the results show that those who follow ADA recommendations routinely have better knowledge and practice scores (p-value 0.00406). Conclusion: More awareness about ADA recommendations and the practice of vitamin B12 screening in T2DM patients who use metformin for family physicians is required, either by encouraging them to order B12 through workshops and continuous learning programs or by the availability of tools needed to test B12.

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