High blood pressure coupled with Alzheimer's may make patients more vulnerable to the effects of the neurological disease, finds a new study.

Researchers at the University of Pittsburgh discovered that high blood pressure reduces the flow of blood to the brain. "While hypertension is not a cause of Alzheimer's disease, our study shows that it is another hit on the brain that increases its vulnerability to the effects of the disease," said study co-author Cyrus Raji, a scientist and Ph.D. candidate at the University of Pittsburgh, in a release.

High blood pressure, in which blood circulates through the body too forcefully, leads to an elevated risk for heart attack, stroke and aneurysm, say researchers.

The findings were presented Tuesday in Chicago at the annual meeting of the Radiological Society of North America.

In the study, MRI images were taken of the brains of:

• 48 older adults — 38 with hypertension and 10 without.
• 20 Alzheimer's patients — 10 with hypertension and 10 without.
• 20 adults with mild cognitive impairment (the first stage of dementia) — 10 with hypertension and 10 without.

High blood pressure reduced the flow of blood to the brain in all patients who suffered from the condition. However, blood flow in the brain was lowest in those people who had Alzheimer's.

"These results suggest that by changing blood flow to the brain, hypertension — treated or untreated — may contribute to the pathology of Alzheimer's," Raji said.

Alzheimer's disease is a progressive, degenerative brain disease, which leads to the severe impairment of thinking and memory, according to the Alzheimer Society of Canada. In 2007, it's estimated 97,000 Canadians will develop Alzheimer's or a related disease.