High blood pressure and large increases in blood pressure in midlife may be linked with poorer brain health in later life, according to a UCL-led study published in The Lancet Neurology.
High blood pressure is known to increase risk for cognitive impairment later in life, but exactly how and when it increases risk is unclear.
For the Insight 46 study, researchers followed 502 people from the Medical Research Council National Survey of Health and Development – the longest running birth cohort in the UK – who were all born in the same week in 1946.
The participants were free from dementia at the start of the study and 465 underwent brain scans to assess their brain health. Due to the nature of the birth cohort, the researchers were able to measure their blood pressure at 36, 43, 53, 60-64 and 69 years.
The brain scans looked for levels of a key Alzheimer’s protein, amyloid, in the brain. The scans also assessed the size of the brain – an indicator of brain health – and the presence of blood vessel damage in the brain.
The results showed that higher blood pressure at the age of 53 and faster rises in blood pressure between 43 and 53 were associated with more signs of blood vessel damage or ‘mini strokes’ in the brain when an individual was in their early 70s.
Higher blood pressure at the age of 43, and greater increases in blood pressure between the ages of 36 and 43, were associated with smaller brain volumes.
Blood pressure was not associated with the amount of amyloid protein in the brain and did not appear to predict memory and thinking problems at this age.
Prof Jonathan Schott, Clinical Neurologist at the UCL Queen Square Institute of Neurology, said: “This unique group of individuals, who have contributed to research their entire lives, has already shaped our understanding of the factors influencing health throughout life. The Insight 46 study has allowed us to reveal more about the complex relationship between blood pressure and brain health. The findings suggest that blood pressure even in our 30s could have a knock-on effect on brain health four decades later.
“We now know that damage caused by high blood pressure is unlikely to be driven through the hallmark Alzheimer’s protein amyloid, but through changes in blood vessels and the brain’s architecture. The findings show that blood pressure monitoring and interventions aimed at maximising brain health later in life need to be targeted at least by early midlife.”
The research was funded by Alzheimer’s Research UK, MRC Dementias Platform UK, Wellcome Trust, Brain Research UK, the Wolfson Foundation and the Weston Brain Institute.
