Metformin x Cognition

Diabetes Drug Metformin May Impair Cognition

Miriam E. Tucker

Sep 24, 2013

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Metformin use in some patients with type 2 diabetes is associated with cognitive impairment that might be alleviated with vitamin B₁₂ and calcium supplementation, a new study from Australia suggests.

This isn't the first time metformin has been linked to cognitive problems stemming from vitamin B₁₂ deficiency, but prior data have been conflicting, lead author Eileen M. Moore, PhD, a medical research scientist in the department of surgery, Deakin University, Geelong Hospital, Barwon Health, Geelong, Australia, told Medscape Medical News.

Up to 30% of patients taking metformin may be deficient in B₁₂, and this is thought to be due to an interaction between metformin and a receptor in the distal ileum, leading to some inhibition in the uptake of the vitamin, she and her colleagues say.

However, she told Medscape Medical News, "Metformin remains a very effective first-line antidiabetic drug and may reduce cardiovascular risk in patients with diabetes. Clinicians and patients should not be alarmed by these findings, but the need to monitor and correct vitamin-B₁₂ levels is highlighted."