Cognitive decline and dementia can be caused by illnesses like Alzheimer’s disease and conditions like high blood pressure, which damage blood vessels in the brain.
A new study from Yale University shows that having both of these conditions significantly increases the risk of cognitive decline.
The study, published in Alzheimer’s & Dementia, used data from a large study called the Systolic Blood Pressure Intervention Trial, which took place between 2010 and 2015.
The new research included data from 467 racially diverse participants, all aged 60 or older, who had high blood pressure.
The researchers looked at two key markers linked to cognitive decline. The first is called “white matter hyperintensity,” which refers to brain scarring caused by damage to small blood vessels, often from high blood pressure.
This was measured using MRI scans. The second marker relates to the buildup of amyloid plaques, which are sticky proteins in the brain that are a hallmark of Alzheimer’s disease.
Although these plaques cannot be easily measured in a living person, researchers used a blood test that checks for certain proteins (Abeta42 and Abeta40) that correlate with plaque levels.
The researchers found that people with both white matter hyperintensity and high levels of amyloid-beta were much more likely to develop cognitive problems. Those with low risk scores for both factors had the lowest rate of cognitive decline (5.3%).
People who had high levels of just one factor had higher rates of cognitive impairment (7.8% for brain scarring and 11.8% for amyloid plaques). However, participants with high levels of both risk factors had the highest rate of cognitive decline (22.6%).
Dr. Adam de Havenon, the lead researcher, said, “We found that having both risk factors greatly increases the chances of cognitive decline. Most cases of dementia aren’t caused by just one thing—there’s usually a mix of factors like Alzheimer’s and vascular issues.”
Dr. de Havenon emphasized the need for more diverse research to fully understand how these risk factors work together. He pointed out that underserved populations are more likely to suffer from high blood pressure, making them more vulnerable to vascular dementia.
With new treatments emerging to slow amyloid buildup, the focus on treating both vascular and Alzheimer’s-related factors is becoming even more important.
“This is a health equity issue,” said de Havenon. “To truly address dementia, we need to include diverse groups in our research and treat both high blood pressure and Alzheimer’s risk factors.”
If you care about dementia, please read studies about dietary strategies to ward off dementia, and how omega-3 fatty acids fuel your mind.
For more health information, please see recent studies about Choline deficiency linked to Alzheimer’s disease, and what to eat (and avoid) for dementia prevention.
