Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: FRIDAY, March 2, 1990 TAG: 9003022822
SECTION: NATIONAL/INTERNATIONAL PAGE: A4 EDITION: METRO
SOURCE: New York Times
DATELINE: LENGTH: Medium
The study, conducted at the University of Washington in Seattle, compared the head trauma history of 130 patients who had Alzheimer's disease with a comparison group of the same number of people in which there had been no clinical diagnosis of the disease.
The researchers found that Alzheimer patients were 3 1/2 times as likely to have suffered head injuries.
The relationship of injury to Alzheimer's held true even when the injury occurred decades before the onset of the debilitating, mind-destroying disease, according to the report in the March issue of The American Journal of Epidemiology.
The reason was unclear but the researchers speculated that it might relate to brain cell damage or to injury to the blood-brain barrier, which prevents almost all substances in the blood from entering brain tissue.
The report by Dr. Amy Borenstein Graves, who is now with the Battelle Seattle Research Center, and colleagues at the university said the study confirmed other work that had found the possible link.
"This study confirms the earlier work, but it still does not prove the association beyond a doubt," she said. "There are now more than eight studies that at least show a trend linking trauma and Alzheimer's disease, although some are not statistically significant".
Graves looked at 70 men and 60 women with diagnosed Alzheimer's disease and paired them with the comparison group of people of the same age, sex, and style and standards of living.
She then interviewed spouses or others who had lived with the patients for a long time to find out if the patients had ever suffered a head injury.
The study found that 24 percent of the Alzheimer's patients and 8.5 percent of those in the control group had suffered at least one past head injury that was serious enough for them to be hospitalized or to seek medical attention.
The most frequent cause of the injuries was automobile accidents, but domestic, occupational and recreational accidents were also factors.
The researchers also tried to measure the severity of the injuries by finding out which ones caused unconsciousness. There proved to be no statistically significant difference between the groups by that measure.
Dr. Lon White, chief of epidemiology with the National Institute on Aging, said that although Graves' study was not definitive, it added evidence to a trend seen in other work for years.
"This work has reaffirmed the belief that many people have that head trauma is a factor in the onset of Alzheimer's disease, but the question needs a lot more study," White said.
With Alzheimer's disease, he said, brain cells die and become disconnected from one another for unknown reasons.
"We still don't know the basic process of Alzheimer's that causes this erosion, but it's not trauma by itself," White said.
"But it makes good clinical sense that trauma might play a significant role if it leads to cell destruction or breaking the connections in the brain."
by CNB