WASHINGTON -- Regular aspirin use appears to reduce the risk of heart attacks brought on by outbursts of anger, researchers said yesterday.
The scientists said surveys of more than 1,600 heart attack patients at dozens of medical centers and hospitals across the country indicate that outbursts of anger more than double the risk of such attacks in the following two hours.
But the researchers, from Harvard Medical School and New England Deaconess Hospital in Boston, said it appeared that the use of aspirin "severs the link" between the heart attack and anger as a triggering episode.
Doctors said that the overall risk of anger triggering a heart attack was small but that the apparent role of aspirin in eliminating this risk shows that it might also be possible to counter other potential triggers of heart attacks, which are often fatal.
"This type of study hopefully will give us clues to the biological links between external stressors and coronary events," said Dr. Murray A. Mittleman, one of the principal investigators. "Once we find the mechanism that links the trigger and the heart attack, we hope to find methods to break that connection."
The study underscores the relationship between aspirin use and the risk of heart attacks. The routine use of aspirin, known to interfere with blood clotting, is recommended for those at risk of heart attacks, and some doctors advise that everyone over age 50 take an aspirin tablet every other day to protect against blood-vessel and heart disease.
At a meeting a year ago, the researchers presented preliminary results showing that anger doubled the risk of heart attacks. The finding that aspirin protects against that higher risk emerged when the study was completed, they said.
Dr. Mittleman, Dr. James E. Muller and colleagues at Harvard said in a report published in the October issue of Circulation, the American Heart Association journal, that the relative risk of a heart attack in the two hours after an episode of anger is 2.3 times higher than usual.
The researchers said the risk that a healthy 50-year-old man would experience a heart attack during any given hour was about 1 in 1 million. The study suggests that the risk increases to 2.3 in 1 million in the two hours after an episode of anger.
Among the people surveyed who reported getting angry, those who regularly used aspirin had a relative risk of heart attack that was 1.4 times as high as normal.
But those who reported anger who did not use aspirin regularly had a risk that was 2.9 times as high.