Blood pressure related to lesions, signs of Alzheimer's in autopsied brains

Elderly people with blood levels above average According to a study published Wednesday in the journal Neurology. In particular, researchers saw increased signs of cerebral infarction, or areas of dead tissue caused by a blockage of blood supply to the brain, during post tissue examination. -Mortem under the microscope.

"We know that blood pressure, especially if it is elevated, is related to stroke and dementia," said Dr. Zoe Arvanitakis, lead author. of the study and professor of neurology at Rush University Medical Center in Chicago

"In this study, we wanted to examine the relationship between blood pressure and a range of values ​​- not only high but also two most common causes of stroke and dementia, "said Arvanitakis. These causes are brain infarctions (also called brain lesions) and characteristic biomarkers of Alzheimer's disease: plaques and tangles, both made of different proteins, in the brain.

Look at Brain Tissue

the force to which blood circulates in our veins, arteries and capillaries, according to the American Heart Association. Too large a force means high pressure; too weak a force means weak.

In figures, high blood pressure is considered something above 140/90. The first number, the systolic pressure, reflects the pressure in the vessels when the heart beats. The second number, diastolic, measures when the heart is at rest. Hypotension is deliberately left undefined because no number is considered too low as long as there are no troubling symptoms like dizziness, nausea and other problems. concentration.

Arvanitakis and his colleagues are committed to understanding blood pressure. The help of 1,288 people, all aged 65 and over and about two-thirds of them are women. Participation included annual physical exams, neuropsychological tests and records of their medical history and medications.

Participants also consented to an autopsy of the brain upon their death;

"What we wanted to do, is look at the actual brain tissue to see if we saw the underlying changes in the brain that cause stroke or the underlying changes in the brain that cause dementia "Arvanitakis said.

Participants' data showed a mean systolic blood pressure of 134 and an average diastolic blood pressure of 71. Two-thirds had a history of hypertension, and 87% had taken medication for hypertension blood. 19659004] "We looked at blood pressure in many different ways," including how changes in blood pressure – such as lowering blood pressure – "could be badociated with brain damage at the time of death," says Arvanitakis. , increased risks

Research found that "the higher the average arterial pressure, the more a person had to have brain damage," said Arvanitakis.

For example, a systolic blood pressure of 147 translates to 46% incr attenuated the risk of having one or more brain lesions, particularly infarction, the badysis showed. This same higher than average systolic pressure (147 vs the group average of 134) also meant 46% greater chances of large lesions plus 36% higher risk of very small lesions, the results indicated.

Mean diastolic blood pressure also showed a relationship with brain damage, the researchers found. The researchers found that people with above average diastolic blood pressure (79 compared to the group average of 71) had an increased risk of 28% of one or more lesions.

Arvanitakis and colleagues found that systolic blood pressure was badociated with more tangles in brain tissue, common sign of Alzheimer's disease – but not at the amyloid plaques, another feature common neurodegenerative disease.

Arvanitakis says that this finding is difficult to interpret. The importance of monitoring blood pressure

Dr. Joe Verghese, professor of neurology and medicine and director of the Resnick Gerontology Center at the Albert Einstein College of Medicine, said the highlights of the new study include high participation rates and badessments of blood pressure and cognition. "

Verghese, who was not involved in the research, added that his main weakness was the somewhat" limited "data available.But he says that the study adopted a" different approach "in his review of brain health in the elderly.

" In previous studies, the focus was on clinically diagnosed dementia "- in a medical office. Still alive, Verghese wrote in a However, Arvanitakis and his colleagues have shown a direct relationship between blood pressure and the signs of stroke and dementia causes: "the presence of vascular pathology in post-mortem brains."

"The study supports the treatment of life to prevent cerebrovascular disease," said Verghese. "The story regarding Alzheimer's risk is less clear."

Yet, previous research , including that of Verg hese, have shown that abnormal blood pressure in the average and late life was badociated with a risk of dementia.

According to Arvanitakis, anyone concerned about a stroke or dementia "should continue to follow current medical recommendations for the management of blood pressure to reduce the risk of cognitive decline and risk of dementia. "Since blood pressure is an important risk factor for the disease, we really need to understand how it affects the brain," she said. "The research really needs the participation of volunteers and needs ongoing scientific funding to continue to make important discoveries."