About half of the study participants had one or more of these, and the risk was greater for those with higher blood pressure. For example, people with an average top reading of 147 had a 46 percent greater risk of having one or more of the bad spots than those with an average top reading of 134. People with higher bottom blood pressure readings also had a greater risk for this problem.
Researchers also found a link between higher pressure and one of the signs of Alzheimer’s — tangles of a protein called tau — but not another Alzheimer’s hallmark, amyloid plaques. This needs further research to understand the implications, Arvanitakis said.
“It’s a pretty strong study,” said James Hendrix, director of global science initiatives at the Alzheimer’s Association. “Autopsy data is really powerful” and has been the gold standard for diagnosing Alzheimer’s for many years, he said.
With Alzheimer’s, changes in the brain occur a decade or more before symptoms do, so high blood pressure may have been doing damage well before the age when these people enrolled in the study, he said.