By Peggy Peck

STOCKHOLM (Reuters Health) - Results of a large study of elderly residents of Finland have identified two important new risk factors for Alzheimer's disease: high blood pressure and high cholesterol. If these risk factors are combined with genetic risk it makes a person eight times more likely to develop Alzheimer's disease.

Dr. Miia Kivipelto of the University of Kuopio in Finland said that these risk factors appear to be just as important as genetic risks for Alzheimer's disease.

Researchers have previously identified a gene, apolipoprotein E-e4, that is associated with late-onset Alzheimer's disease, meaning disease that causes loss of memory and other cognitive problems in people aged 75 or older. This is the most common type of Alzheimer's disease and, worldwide, about one in four people carry at least one copy of the so-called Alzheimer's gene.

"We can't do anything to change the genetic risk," Kivipelto told Reuters Health. "But high blood pressure and high cholesterol can be controlled with medical treatments."

Kivipelto presented the new research at the 8th International Conference on Alzheimer's Disease and Related Disorders.

She and her colleagues studied 1,449 individuals who had been followed by Finnish epidemiologists since 1972. The findings were based on data collected in evaluations conducted in 1998, after a follow-up of up to 21 years. Seventy-three percent of the study volunteers ranged in age from 65 to 79.

Kivipelto said that individuals who carried the so-called Alzheimer's gene were about twice as likely to have developed the disease than those who had no genetic predisposition.

"But if they also had high blood pressure, the person is five times more likely to develop Alzheimer's disease. When high cholesterol is added, the risk is eightfold higher than healthy people with no genetic risk," she said.

She said that the association between Alzheimer's disease and high blood pressure only relates to systolic pressure, which is the first or higher number in a blood pressure reading. Elevated systolic blood pressure is known risk factor for stroke.

"We found no relationship with diastolic pressure," she said. Diastolic is the second, or lower number in a blood pressure reading.

A second study from a team of French researchers found that a history of high blood pressure is linked to Alzheimer's disease.

In that study, researchers reviewed medical records from 1,560 elderly patients treated at a memory clinic. Sixty-seven percent of patients who were diagnosed with probable Alzheimer's disease and 78% of patients with vascular dementia had a history of high blood pressure. Among patients who were not diagnosed with dementia, 56% had a history of high blood pressure.

Dr. William Thies, vice president for medical and scientific affairs at the Alzheimer's Association, said these studies offer more evidence that "Alzheimer's disease is tracking vascular risk factors."

Last Updated: 2002-07-23 10:00:25 -0400 (Reuters Health)