MONDAY, May 9, 2005 (HealthDay News) -- Cocaine users seem to have an unusually high incidence of coronary artery aneurysms, weakened areas of heart blood vessels that raise the risk of heart attacks, new research finds.
The study included 191 men and women in their 40s who had angiography, an X-ray of blood vessels, because of known or suspected heart disease. Aneurysms were found in 34 of the 112 persons who reported using cocaine and only six of 91 nonusers.
The study, by physicians at the Minneapolis Heart Institute Foundation, appears in the May 10 issue of Circulation.
That higher incidence of aneurysms may help explain why cocaine users have been found to have a high risk of heart attacks, said Dr. Timothy D. Henry, director of research at the foundation.
Henry suggested two possible explanations for the increased incidence of aneurysms.
"Cocaine use causes periodic hypertension, periods when the blood pressure goes up sharply," he said. "Having such episodes of high blood pressure over the course of time can lead to formation of aneurysms."
Cocaine is also known to damage the endothelium, the delicate lining of blood vessels, which could contribute to the weakening of the arteries, Henry said.
Whatever the explanation, the report is "another reason to tell people how dangerous cocaine is," he said.
The study cited estimates by the federal Substance Abuse and Mental Health Services Administration that 27.7 million Americans -- 12 percent of those 12 and over -- had used cocaine at least once in 2001, and that 1.7 million had used it in the previous month.
Most studies of cocaine and heart damage have concentrated on immediate problems, Henry noted. The new study raises the possibility that even short-term use can cause damage decades later, he said. One man in the study who was found to have an aneurysm said he had used cocaine heavily for a two-year period 15 years earlier, Henry said, so the drug "can cause long-term damage that you have to live with the rest of your life."
Dr. Murray Mittleman, director of the Cardiovascular Epidemiology Research Unit at Beth Israel Deaconess Medical Center in Boston, said the new study "provides clues to the mechanisms of heart attacks occurring in people who are cocaine users."
"It is an important step forward in understanding the biology of what happens in cocaine use," Mittleman said.
But follow-up studies are needed because of the way the study was carried out, he said.
"They didn't start out looking at people who used cocaine," Mittleman said. "They looked at people who had angiography for some clinical reason. It is possible that this is a special group of cocaine users."
Nevertheless, the report "gives some insight into why we observe a higher rate of cardiac problems in cocaine users," he said.
For more on cocaine's risks to the heart, visit the American Heart Association.