August 20, 2019

expert reaction to a study looking at midlife blood pressure and brain volume

Research, published in The Lancet Neurology, reports that high blood pressure and rising blood pressure between the ages of 36 and 53 are associated with smaller brain volume and white matter lesions in later years.

Dr Karen Doyle, Senior Lecturer in Physiology, National University of Ireland Galway, said:

“The Lancet press release is entirely accurate and reflects both the paper and the editorial commentary well. The ARUK press release is also mainly accurate, but I would suggest the removal of the term ‘mini strokes’’, as the paper does not specifically talk about that, and I would also suggest that the last paragraph starting with ‘The Insight 46 study…’ be slightly changed, replacing ‘worse brain health’ with ‘higher blood pressure’.

“The study itself is very high-quality research, with solid data and sound conclusions. It is an excellent addition to existing literature, contributing to understanding the link between cerebrovascular health in middle age and healthy ageing of the brain.

“It clearly implicates high blood pressure as a cause of white matter lesions and smaller brain volume later in life. It also distinguishes between the effect of high blood pressure on two known causes of dementia – small cerebral blood vessel disease is increased with high blood pressure, but there is no significant link to the amyloid pathology of Alzheimer’s disease.

“The Insight 46 participants are only 70 years old in this study – still relatively young. A limitation to this study that is acknowledged by the authors is that the sample is composed of people with fewer health problems than average and is exclusively composed of white people. Nevertheless, the overall conclusion that earlier monitoring and intervention to reduce high blood pressure will help to protect the brain as we age, is sound.”

Prof Clive Ballard, Professor of Age-Related Diseases, University of Exeter Medical School, said:

“We need to be a bit cautious about interpreting the very specific age bands used in this paper, however it does provide further evidence highlighting blood pressure as a key dementia risk, and importantly extends this high risk period to mid to late 30s, which is younger than the 40s and 50s period highlighted by our 2017 Lancet Commission.

“The take-home message here is that it’s important to monitor blood pressure from your 30s onwards. If you have high blood pressure, get it treated regardless of your age, as you may well be protecting your brain as well as your heart.”

Dr James Pickett, Head of Research, Alzheimer’s Society, said:

“The management of blood pressure is emerging as one of the more robust and modifiable risk factors for dementia, particularly in mid-life. The major strength of this study is that it used a series of measures across a period of around 33 years, giving researchers an impression of how changes in the person’s blood pressure can reflect changes in the brain or risk of dementia.

 “The unique point that all people in the study have been followed since in 1946, all growing up during a period when there were big developments in treatment of blood pressure. It will be interesting to look at people outside of this specific group, as Alzheimer’s Society are funding in the PREVENT study where the group is about 20 years younger, so the results can be used to draw conclusions for the wider population.

 “We know what’s good for the heart is good for the brain, this research shows that it is never too early to start thinking about you can do to maintain healthy blood pressure – from eating a balanced diet to avoiding smoking and excessive drinking. Another good place to start the conversation for people over the age of 40 is with an NHS Health Check with a health professional every five years.”

Prof Paul Leeson, Professor of Cardiovascular Medicine, University of Oxford, said:

“We have known for some time that people who have higher blood pressure tend to have different brain structure in later life. What doctors have been debating is whether treating high blood pressure in young people actually prevents these brain changes. The alternative, which is what we tend to do right now, is wait until later in life to start to take high blood pressure seriously because we know that, by then, the more severe brain changes are definitely developing.

“A unique strength of this new study is that the people involved have been taking part in the research for many decades. This has allowed the authors to study how variations in blood pressure when they were young associate with brain structure when the participants reached their 70s.

“The group taking part is relatively small so it is difficult to make strong conclusions, and this new paper is not a trial, so we still do not know whether treating the high blood pressure when the participants were younger could have prevented these differences in the brain. However, the findings do support the idea that there may be critical periods in life, such as in your 30s and 40s, when periods of high blood pressure are accelerating damage within the brain.”

Prof Tara Spires-Jones, UK Dementia Research Institute Programme Lead and Deputy Director, Centre for Discovery Brain Sciences, University of Edinburgh, said:

“This study led by Prof Schott and Prof Fox at UCL examined relationships between high blood pressure in mid-life and later life brain structure changes. They observed that high and increasing blood pressure from age 36 was associated with smaller brain volumes and increased markers of damage to blood vessels in the brain at age 69-71. Based on these data, authors suggest it may be beneficial to begin monitoring blood pressure in people in their 30s and to begin treating people with high blood pressure early to maximise brain health in older age. 

“This study is well conducted and adds to what we know about how blood pressure affects the brain during ageing. This study does not directly support a link between blood pressure and Alzheimer’s disease as the scientists did not see any associations between blood pressure and cognitive ability or the accumulation of Alzheimer’s related amyloid pathology. However, this study does strongly support the notion that taking good care of ourselves in mid-life is important for maintaining a healthy brain during ageing.”

‘Associations between blood pressure across adulthood and late-life brain structure and pathology in the neuroscience substudy of the 1946 British birth cohort (Insight 46): an epidemiological study’ by Laneby et al. was published in The Lancet Neurology at 23:30 UK time on Tuesday 20^th August. 

DOI: 10.1016/S1474-4422(19)30228-5

Declared interests

Prof Paul Leeson: Receive research grants from Wellcome Trust and British Heart Foundation related to high blood pressure and brain changes in young adults.

Prof Tara Spires-Jones: I have no conflicts of interest with this study.

None others received.