People taking certain drugs for their blood pressure may have a reduced risk of developing dementia, a new study indicates.

It involved almost 800 older men who had been taking part in a study on ageing. Just over 600 of the men had high blood pressure and more than half of these were being treated with medication for the problem. After the men's deaths, autopsies were carried out.

The study found that those who had been taking drugs known as beta blockers for their high blood pressure, had fewer abnormalities in their brain. These abnormalities can be signs of different types of dementia, including Alzheimer's disease.

The scientists noted that overall, all types of blood pressure drugs were better for the brain than no medication. However, those who had taken just beta blockers had fewer changes in their brains than those who had received other blood pressure drugs or who had not been treated for the problem.

The study also noted that those who had taken beta blockers, whether alone or in combination with other blood pressure drugs, experienced a lot less shrinkage in their brains.

"With the number of people with Alzheimer's disease expected to grow significantly as our population ages, it is increasingly important to identify factors that could delay or prevent the disease," the scientists from Honolulu said.

They described the results of this study as ‘exciting', particularly as beta blockers are a common treatment for high blood pressure.

Details of these findings are due to be presented at the American Academy of Neurology's annual meeting in San Diego in March.

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