The research, led by Garvan Institute of Medical Research and the Centre for Healthy Brain Ageing (CHeBA), University of New South Wales (UNSW) in Australia studied the cognitive function change of 1037 Australians, aged between 70 to 90 years old during six-year period, reports Xinhua.

The research revealed among all participants who had type 2 diabetes, those taking metformin had a significantly slower cognitive decline and lower dementia risk compared to those not taking metformin.

The study also identified that the rate of decline in cognitive function was the same during the 6-year period between participants with type 2 diabetes taking metformin and those without diabetes.

The first author, Professor Katherine Samaras from Garvan Institute of Medical Research said type 2 diabetes patients have higher chance of developing dementia due to their inability to maintain blood glucose levels within a normal range.

"As they age, people living with type 2 diabetes have a staggering 60 percent risk of developing dementia, a devastating condition that impacts thinking, behaviour, the ability to perform everyday tasks and the ability to maintain independence," Samaras said.

"This has immense personal, family, economic and societal impacts."

Researchers suggested metformin may not only have cognitive benefits for people living with type 2 diabetes but could also help those without diabetes but at risk of cognitive decline.

"To establish a definitive effect, we are now planning a large, randomised controlled trial of metformin in individuals at risk of dementia and assess their cognitive function over three years," Samaras said.

"This may translate to us being able to repurpose this cheap medication with a robust safety profile to assist in preventing against cognitive decline in older people."

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