Prevalence of Megaloblastic Anemia in Type 2 Diabetes Patients Taking Long-term Metformin with Vitamin B Supplements

Authors

  • Punyaporn Tonmanee Department of Food and Pharmaceutical Chemistry, Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok, Thailand
  • Panida Sombatjareankit Department of Food and Pharmaceutical Chemistry, Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok, Thailand
  • สุธิดา จันทร์เจนจบ Department of Pharmacy, King Chulalongkorn Memorial Hospital, Bangkok, Thailand
  • Tippawan Siritientong Department of Food and Pharmaceutical Chemistry, Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok, Thailand

Keywords:

megaloblastic anemia, metformin, vitamin B, type 2 diabetes mellitus

Abstract

Long-term use of metformin is associated with vitamin B12 deficiency, which can lead to megaloblastic anemia. Vitamin B supplementation is often provided to patients receiving metformin. This cross-sectional descriptive study aims to investigate the prevalence of megaloblastic anemia in patients with type 2 diabetes
receiving long-term metformin with vitamin B supplementation. The data were collected from the Outpatients Department at King Chulalongkorn Memorial Hospital, Thai Red Cross Society, from January 1st, 2023, to
December 31st, 2024.


Out of a total of 161 patients, 113 (70.2%) were female. The median age is 74 years (interquartile range 65-81 years). Dose per day of metformin ranged from 1,000 to 3,000 milligrams. The most common comorbidities were hypertension and hyperlipidemia (126 patients; 78.26%). The most prescribed oral vitamin B products were vitamin B complex (79 patients; 63.49%) which contain vitamin B 12 20-200 micrograms per tablet. The prevalence of megaloblastic anemia in this study was 2.5% (4 out of 161 patients). However, no
correlation was found between the dose of metformin and the dose of vitamin B12 in vitamin B supplement products with the occurrence of megaloblastic anemia in this group of participants (p-value = 0.824 and
p-value = 0.358, respectively).
Megaloblastic anemia is still found in patients with type 2 diabetes who have received long-term metformin with vitamin B supplementation. However, due to the small sample size and the unknown adherence to the medications among the patients, further studies are needed

References

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Published

2025-12-25

How to Cite

Tonmanee, P. ., Sombatjareankit, . P. ., จันทร์เจนจบ ส. ., & Siritientong, T. (2025). Prevalence of Megaloblastic Anemia in Type 2 Diabetes Patients Taking Long-term Metformin with Vitamin B Supplements. Thai JPEN วารสารโภชนบำบัด, 33(2), 1–10. retrieved from https://he02.tci-thaijo.org/index.php/ThaiJPEN/article/view/275485

Issue

Vol. 33 No. 2 (2025): กรกฏาคม-ธันวาคม 2568

Section

Research article

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