High blood pressure is associated with a 62 per cent higher risk of vascular dementia, according to an analysis of medical records.

Having high blood pressure could significantly raise your risk of developing the second most common form of dementia, says a new study.

The medical records of 4.28 million people in the UK were analysed by The George Institute for Global Health researchers.

They found heightened blood pressure was associated with a 62 per cent higher risk of vascular dementia between the ages of 30-50 and a 26 per cent higher risk at age 51-70.

"Vascular dementia rates are increasing all over the world and will pose a significant economic and social burden in both developed and developing countries," said lead author Professor Kazem Rahimi.

"We already know that high blood pressure can raise the risk of stroke and heart attack.

"Our research has shown that high blood pressure is also associated with a significantly higher risk of vascular dementia."

The UK records revealed that over a seven-year period, 11,114 people went on to develop vascular dementia.

The condition affects about 9.3 million people globally and is caused by reduced blood supply to the brain due to diseased blood vessels.

The study, published in Stroke, also found that high blood pressure was still a risk factor even after adjusting for the presence of stroke, the leading cause of vascular dementia.

"Our results suggest that lowering blood pressure, either by exercise, diet or blood pressure lowering drugs, could reduce the risk of vascular dementia," Prof Rahimi said.

High blood pressure causes problems by damaging and narrowing the blood vessels in the brain.

Over time, this raises the risk of a blood vessel becoming blocked or bursting.