Linking Blood Pressure to Dementia

High blood pressure in middle age may have helped forecast memory loss in a new study

/ Author:  / Reviewed by: Joseph V. Madia, MD Beth Bolt, RPh

(RxWiki News) Keeping blood pressure in check is high on the priority list for many older people, mainly because blood pressure tends to rise with age. And blood pressure that's out of whack can signal a serious health problem.

Middle-aged people with high blood pressure were more likely than those with lower blood pressure to have spinal fluid containing molecules that are linked with Alzheimer's disease, according to a new study.

None of those affected 55- to 70-year-old study participants, however, showed symptoms of Alzheimer's.

Alzheimer's is the most common cause of premature, severe memory loss.

"Eat healthy and exercise to help lower high blood pressure."

Daniel Nation, PhD, a researcher at Veterans Administration (VA) San Diego Healthcare System in California, was this study's lead author.

The study enrolled 177 participants aged 55 to 100 who had been treated at either the University of California San Diego Alzheimer’s Disease Research Center, University of Washington or Oregon Health and Sciences University.

The researchers measured the pulse pressure of each participant by subtracting the top number of their standard blood pressure reading from the bottom number. Pulse pressure increases with age and is one way of determining the age and health of the body's blood vessels. Spinal fluid also was taken from study participants.

In addition to having no Alzheimer's symptoms, no study participant had ever had a stroke. Some strokes happen when cholesterol-clogged blood vessels cause blood pressure to spike.

Previous studies, these researchers wrote, have linked high pulse pressure to Alzheimer's-related memory loss — also known as dementia — even in patients older than 75 who had not had a stroke and didn't have high blood pressure.

That was one of the reasons they began their own investigation involving the 177 study participants.

What these researchers concluded is that study participants aged 55 to 70 had elevated levels of the amino acid and protein found in the brain lesions discovered during autopsies on Alzheimer's patients who died. The same elevated levels and lesions were not found in study participants who were older than 70.

“This is consistent with findings indicating that high blood pressure in middle age is a better predictor of later problems with memory and thinking skills and loss of brain cells than high blood pressure in old age,” Dr. Nation said.

“These results suggest that the forces involved in blood circulation may be related to the development of the [main] Alzheimer’s disease signs that cause loss of brain cells,” he said.

This study was published online November 13 in Neurology.

The Alzheimer’s Association, National Institutes of Health, University of Washington and Oregon Health Sciences University funded this study.

One of the study's eight authors has been a paid consultant to two major pharmaceutical companies.

Review Date: 
November 13, 2013
Last Updated:
December 30, 2013