News - Hypertension Week of Sept 28, 2003/ Vol. 2 No. 39

Study: High Blood Pressure May Be a Factor in "Senior Moments"

Reduced blood flow to the brain caused by high blood pressure may cause older people to have short-term memory problems, according to a study presented September 23 at an American Heart Association conference in Washington D.C.

Using brain imaging to detect the metabolic activity of the brain during certain tasks, the researchers found that people with high blood pressure get less blood to the brain than people with normal blood pressure.

"The reduced blood supply reduces the brain's ability to perform needed tasks, such as remembering an unfamiliar phone number," said study author J. Richard Jennings, professor of psychiatry and psychology at the University of Pittsburgh in Pennsylvania.

In the study, the researchers defined high blood pressure as a reading of 140 over 90 or higher. The study involved 59 people with normal blood pressure and 37 people with high blood pressure. The average age of the participants was about 60 years.

The brain scans showed that blood flow was not as rapid or full among people with high blood pressure as it was in those with normal blood pressure. The diminished blood flow correlated to slightly poorer scores on memory tests, according to Jennings.

When a person has high blood pressure, the brain protects itself by remodeling its blood vessels to compensate. This vascular remodeling, said Jennings, probably explains the blood flow differences observed with the brain scans.

For that reason, Jennings explained that blood pressure medicines that specifically address vascular changes -- such as angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARBs) -- are most likely to increase brain blood flow.

Jennings added that one way to look at high blood pressure is to think of it as adding a few years to mental age.