Metformin diabetes drug could double as treatment for dementia

A new study has revealed that the most widely used diabetes medication metformin may cut the risk of dementia for people with type 2 diabetes.
Researchers at Kaiser Permanente in Oakland, California, analysed data on nearly 15,000 people with type 2 diabetes aged 55 or older. All of those included in the study had just started a course of one of four drug treatments – metformin, sulfonylureas, thiazolidinediones (TZDs) or insulin – for their condition when the analysis began.
During the next five years, nearly 10% of the patients were diagnosed with dementia, though the researchers were not able to differentiate between Alzheimer’s disease and other forms of dementia.
After adjusting for a number of risk factors, including age, race, blood sugar control, duration of diabetes, and education, the team found that people taking metformin were 20% less to develop dementia than those on sulfonylureas (baseline group). No difference in dementia risk was seen for those taking TZDs or insulin.
“In diabetic patients, those initiating metformin had a five year reduced risk of dementia in comparison to patients initiating other therapies,” study author Dr Rachel Whitmer and colleagues concluded.
“These results are preliminary evidence that benefits of insulin sensitizers may extend beyond glycemic control to neurocognitive health.”
Dr Whitmer said one theory behind this additional health benefit is that metformin may play a role in the development of new brain cells (neurogenesis). It has also been linked to reduced inflammation, she added.
The researchers now hope to conduct further research to determine whether long-term use of metformin and larger doses of the drug have an effect on the risk of dementia, as well as whether there would be a difference in risk reduction based on the type of dementia.
The findings were presented on Monday 15 July at the Alzheimer Association International Conference (AAIC) in Boston.