A drug used to treat type 2 diabetes could significantly reduce the chances of developing dementia, research suggests.
Type 2 diabetics are known to be at increased risk of developing dementia, and the risk increases the longer or more severe their diabetes is.
Researchers found that those taking sodium-glucose cotransporter-2 (SGLT-2) inhibitors to treat diabetes cut their risk of dementia by up to half compared with those who did not take them.
Although these are preliminary findings, the results suggest that repurposing existing drugs has “enormous potential” to help reduce the risks of other diseases.
Researchers analyzed data from 110,885 type 2 diabetics aged 40 to 69 years from the Korean National Health Insurance Service.
They looked at patients taking SGLT-2 inhibitors, which reduce the amount of glucose (sugar) that the kidneys reabsorb, allowing it to leave the body in urine.
Type 2 diabetics are known to be at increased risk of developing dementia, and the risk increases the longer or more severe their diabetes is.
Diabetes is now a “rapidly escalating crisis” in the UK as the number of people suffering from the disease is believed to have passed five million.
These were then compared to those taking dipeptidyl peptidase 4 (DPP-4) inhibitors, known as gliptins, which work by blocking an enzyme that helps the body increase insulin levels after eating.
During the average follow-up of about two years, 1,172 people were diagnosed with dementia.
Overall, dementia rates were 35 percent lower for those taking SGLT-2 inhibitors compared with other medications.
This figure rose to 52 percent for patients with vascular dementia and 39 percent for Alzheimer’s disease, according to the results published in the BMJ.
The researchers suggest that the risk reduction improved the longer a person took the drugs, and the scientists suggest it could affect inflammation in the brain, reducing the risk of stroke, or modulating glucose metabolism in the brain.
Further “robust clinical trials” are now needed to determine whether this could be a viable treatment in the future, they said.
Dr Jacqui Hanley, head of research at Alzheimer’s Research UK, said: ‘It’s encouraging to see large studies exploring whether drugs that have already been authorised could be repurposed as treatments for dementia.
‘Since these drugs have already been shown to be safe for use in people, this could potentially speed up the process of testing them in clinical trials against dementia, as well as making it significantly cheaper.’
He added: “More generally, the idea of repurposing existing drugs to treat diseases that cause dementia has enormous potential.”
This comes a week after regulators gave the green light to the first drug shown to slow the progression of Alzheimer’s, but refused to authorise lecanemab for use on the NHS on cost grounds.
Professor William Whiteley, professor of neurology and epidemiology at the University of Edinburgh, cautioned that the findings could be due to a “quirk of the study design”.
He said: ‘People with diabetes have a higher risk of dementia, so it is important to find drugs to reduce this risk.
‘Unfortunately, one can never be sure of the effects of a drug by looking at clinical history data.’