Lowering blood pressure reduces risk of developing dementia, research shows

Reviewed by Emily Henderson, B.Sc.May 21 2020

Research completed in NUI Galway has shown that lowering blood pressure by taking blood pressure medications reduces the risk of developing dementia and cognitive impairment by 7%. The findings are published today in a leading international medical journal, the Journal of the American Medical Association (JAMA).

Fourteen randomized controlled trials (96,158 participants) were included in this systematic review and meta-analysis. Blood pressure-lowering with antihypertensive medications reduced the risk of developing dementia or cognitive impairment by 7%, and cognitive decline also by 7% over a four-year period.

When you consider how common dementia is in the population (50 million people worldwide), effective treatment and control of hypertension would have a major impact on preventing dementia. Our findings emphasize the need for more effective screening, prevention, and treatment of hypertension, which remains suboptimal in Ireland.

We know from The Irish Longitudinal Study on Aging that two-thirds of people aged over 50 in Ireland have hypertension (high blood pressure), of which half are unaware of the diagnosis, and one third are not on treatment. This is a major care gap."

Dr Conor Judge, joint first author and Wellcome Trust Health Research Board Irish Clinical Academic Training (ICAT) fellow

This study aimed to gather all the evidence from previous trials of blood pressure-lowering medications and estimate how much the risk of dementia can be reduced by taking blood pressure-lowering medications in people who are diagnosed with high blood pressure. Blood pressure-lowering reduces the risk of stroke and heart disease. Prevention of dementia can now be added to the benefits of treating hypertension. Importantly, there are no available therapies that directly prevent dementia, so this study highlights the critical importance of blood pressure in the risk of dementia.

Prevention of dementia is a major health priority. We know from previous research that a major concern of older people is developing dementia. The message from this study is simple: Get your blood pressure checked. If it is high, it can be readily treated with lifestyle changes and medications. We would hope that our study will heighten awareness of the importance of controlling blood pressure to maintain "brain" health, combined with a healthy lifestyle."

Dr. Michelle Canavan, Consultant Geriatrician at Galway University Hospital, and senior author of the paper

The research was funded by Wellcome Trust, HRB, HSE and NUI Galway through the ICAT program.