A drug long used by epilepsy patients to prevent seizures may lower the risk of heart attacks among people who don't otherwise need the drug, doctors at the University of Maryland Medical Center have found.
Reporting yesterday at an American Heart Association scientific meeting in Dallas, the Maryland researchers said that relatively low doses of the drug Dilantin raised levels of "good" cholesterol by more than 12 percent, on average, reducing the patients' theoretical risk of heart attack by 36 percent.
"We saw this effect at close to three months" after patients began taking the drug, said Dr. Michael Miller, director of preventive cardiology at UM. The study only lasted three months but, "We think Dilantin's effect may increase if administered over longer periods of time," he said.
Dr. Miller ran the $60,000 study in cooperation with the University of Alabama at Birmingham. It was paid for by the National Institutes for Health and Parke-Davis, manufacturers of Dilantin.
Keeps arteries clean
"Good" cholesterol, also known as high-density lipoproteins (HDL), have recently been found to foil the artery-clogging effects of "bad" cholesterol, or low-density lipoprotein (LDL).
Patients with too little clog-fighting HDL in their blood -- a condition that may have genetic origins -- have an increased risk of coronary artery disease, even if their "bad" LDLs are low, too.
Dilantin's ability to lower the risk of coronary artery disease had been noted previously in epileptics, but it was not clear whether non-seizure patients could also benefit.
Michael Crehan, a 39-year-old Westinghouse executive from Ellicott City, Md., does not have seizures, but his family history is full of heart disease. His HDL blood levels were just 32 milligrams per deciliter of blood. The healthy range is considered to be 45 to 50 mg/dL for males, and 50 to 60 mg/dL for females.
Mr. Crehan joined the study, and after three months on Dilantin he showed an HDL level of 39, a jump of nearly 22 percent. There were no side effects.
Lacks federal approval
Now that the study is over, however, Mr. Crehan can no longer get the drug to raise his HDL levels because phenytoin, the generic name for Dilantin, is not yet federally approved for that purpose.
"I'd like to, obviously, now that I know how much it helped. I don't want to wind up like my father," he said.
Mr. Crehan's father, Earl Crehan Sr., underwent surgery in 1991 to bypass four clogged heart arteries. His ordeal awakened his three sons to their own high risk for heart disease.
"All my male relatives died in their 50s, and my father [at the time of his surgery] was the oldest surviving male, at 58," he said.
Michael and his brother Earl joined the study with 37 other men and two women in Baltimore and Birmingham, Ala., all chosen for their low HDL levels. Six had coronary artery disease, and 18 had a family history of heart disease. They averaged 45 years old.
For three months they all ate the same low-salt, low fat diet. Half received the Dilantin, while the others took a placebo.
At the end of the study, Dr. Miller found that HDL levels in the patients receiving the Dilantin averaged 12.4 percent higher, with no side effects.
The control group showed no improvement.
If a larger and longer study were to show that Dilantin also prevents or postpones heart attacks, he said, the drug could become a low-cost preventive medicine for patients at high risk for heart disease due to low HDL counts.