This Article  • Full text  • PDF  • Send to a friend  • Save in My Folder  • Save to citation manager  • Permissions  Citing Articles  • Contact me when this article is cited  Related Content  • Related letter  • Similar articles in this journal  Topic Collections  • Nutrition/ Malnutrition  • Adverse Effects  • Diabetes Mellitus  • Alert me on articles by topic

Kai Ming Chow, MRCP; Rose Zhao-Wei Ting, MBBS; Cheuk Chun Szeto, FRCP, MD

	Since this article does not have an abstract, we have provided the first 150 words of the full text and any section headings.

In reply

We appreciate the comments from Andrès and Federici and agree that food-cobalamin malabsorption accounts for metformin-associated vitamin B₁₂ (cobalamin) deficiency.¹ Whether the use of histamine₂-receptor blockers or proton pump inhibitors confers an increased risk of vitamin B₁₂ deficiency cannot be properly addressed in our study because it was impossible to ascertain the history of consuming those agents, either prescribed or, more importantly, purchased over the counter.

It was suggested by Lev that selection bias would have resulted in the overestimation of the strength of the association between vitamin B₁₂ deficiency and higher doses of metformin. We believe the selection strategy we used is unlikely to affect the robustness of our findings because both cases and controls in our study had at least 1 serum vitamin B₁₂ sample (and hemoglobin A_1c) checked for clinical . . . [Full Text of this Article]

AUTHOR INFORMATION

RELATED LETTER

Metformin and Vitamin B₁₂ Deficiency: Association and Not Causation May Play a Major Role in Cohort Studies
Ishay Lev
Arch Intern Med. 2007;167(7):730.
EXTRACT | FULL TEXT