High blood pressure linked to vascular dementia

High blood pressure could significantly raise the risk of developing the second most common form of dementia, according to a new study from The George Institute for Global Health published in the journal of the American Heart Association.

The medical records of more than four million people were analysed with researchers finding heightened blood pressure was associated with a 62 per cent higher risk of vascular dementia between the ages of 30-50.

Lead author Professor Kazem Rahimi, of The George Institute for Global Health, said: “Vascular dementia rates are increasing all over the world and will pose a significant economic and social burden in both developed and developing countries. So these results are particularly important.

“We already know that high blood pressure can raise the risk of stroke and heart attack,” says Dr. Vivekanand Jha, executive Director, George Institute for Global Health, India, who was not directly involved in the study.  “What makes this study significant is that it   has for the first time shown that high blood pressure is also associated with a significantly higher risk of vascular dementia.”

Vascular dementia affects around 700,000 people in India and is caused by reduced blood supply to the brain due to diseased blood vessels.

High blood pressure cause 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. It’s a known risk factor for stroke and cardiovascular disease but until now studies were conflicting over the risks for vascular dementia with several even indicating that low blood pressure was associated with an increased risk of dementia.

Key findings

  • The team at The George Institute analysed the medical records of 4.28 million people in the UK.
  • They found over a seven year period 11,114 people went onto develop vascular dementia.
  • The study found patients aged 30-50, who had high blood pressure, had a 62 per cent higher risk of vascular dementia, and a 26 per cent higher risk at age 51-70.
  • The study 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.

Professor Rahimi, Deputy Director of The George Institute, said: “Our results suggest that lowering blood pressure, either by exercise, diet or blood pressure lowering drugs, could reduce the risk of vascular dementia.”

The study was supported by the NIHR Oxford Biomedical Research Centre, the NIHR Career Development Fellowship, the Rhodes Trust, the Australian Health and Medical Research Council, the Oxford Martin School, the Wellcome Trust, the Medical Research Council, the Dunhill Medical Trust and the Stroke Association.