Metformin therapy appears to slow the rate of cognitive decline in people with type 2 diabetes and might have the potential to protect against dementia even among those with no diabetes, Australian researchers suggest.

Findings from the NHMRC-funded observational study add to a growing body of evidence supporting the anti-ageing benefits of the agent, they say.

Drawing upon the longitudinal Sydney Memory and Ageing Study, the team analysed data from 1037 elderly participants without dementia, of whom 123 had diabetes (67 treated with metformin; 56 without).

During a six-year period, a battery of neuropsychological tests were used to measure cognitive function every two years in the group, who were aged between 70 and 90 at baseline.