New Study Says Diet Can Heal Arteries
By DANIEL GOLEMAN
Published: November 15, 1988
LIFE-STYLE changes alone, without drugs or surgery, can can halt or reverse atherosclerosis, a hardening of the arteries that can lead to heart attack, researchers reported yesterday.
They cautioned that the findings were preliminary results of a study involving only a few patients. But researchers said the report could have far-reaching implications for the treatment of heart disease.
''It's extremely important to show that without drugs, just by changing people's life style, you can get coronary artery disease to regress,'' said Dr. Alexander Leaf, director of the Cardiovascular Health Center at Massachusetts General Hospital in Boston. ''This is going to shake up physicians' thinking.''
The finding was surprising because scientists only recently discovered that they could shrink the plaque that clogs arteries, and that was with the help of powerful drugs.
The researchers were led by Dr. Dean Ornish, an assistant clinical professor of medicine at the University of California-San Francisco. He said the results are considered preliminary because he has analyzed data from just 29 of the 50 patients in his study. Final results from the others will be available within a year.
''If the results continue to be as good from the study, it will be very important in making physicians consider alternatives to heart transplants, bypasses, and the other high tech medicine they've embarked upon,'' added Dr. Leaf, who is chairman of the Department of Preventive Medicine at Harvard Medical School and a former chief of medicine at Massachusetts General Hospital.
Dr. Ornish presented the findings at a meeting of the American Heart Association in Washington.
The subjects in the study had all been told, on the basis of an angiogram, that they had severe heart disease. Fifty patients were randomly assigned to one of two groups. One group received traditional care, including advice on lowering their cholesterol levels and blood pressure, as well as advice on quitting smoking.
Those in the second group were given a more demanding regimen. They were put on a low-fat, vegetarian diet in which less than 10 percent of calories from fat, most of that was unsaturated. This level is less than a third of the fat in the average American's diet. The patients also received an individual program of moderate exercise, and they were given stress-management training, including yoga and meditation. Those who smoked were required to quit. Measurable Widening
A comparison of the 12 patients who have finished the rigorous program, with 17 who followed the customary treatment showed that those in the experimental program had a measurable widening of arteries.
There usually are no symptoms of disease until the arteries that provide blood to the heart are about 70 percent blocked by plaque. At that point, a person may experience chest pain. If the blockage continues, it can lead to a heart attack.
Before treatment, the doctors determined that, on average, the coronary arteries in patients in the treatment group were 44.4 percent blocked. In averaging, the researchers considered all arteries, meaning that some were at least 70 percent blocked, but others were relatively open. After one year, the average blockage improved to 40.8 percent, and Dr. Ornish said the greatest improvement was in the arteries that had been the most clogged.
In contrast, the average blockage increased in those who received customary care, from 44.1 percent, to 46.2 percent.
The reversal was found in 10 of 12 patients in the experimental treatment group, while 11 of 17 patients in the control group got worse. Cholesterol Levels Tested
Cholesterol in the blood is a primary cause of the progressive blocking. The researchers tested the patients in the study both for total cholesterol, and for low-density lipoprotein cholesterol, which leads to the buildup of plaque.
In the treatment group, the total cholesterol averaged 213 milligrams per deciliter of blood before therapy. It fell to 154 a year later. The LDL level for these patients started at 136, and fell to 81.
In the control group, the average for total cholesterol started at 251, and fell to 230. For LDL, the group averaged 171 milligrams per deciliter, which fell to 148.
The only other major study that has shown the reversal of coronary blockage was reported last year by Dr. David H. Blankenhorn of the University of Southern California. He used a new drug, colestipol, in combination with large doses of niacin, and said the arterial blockage was reversed in 16 percent of his patients.
''Dr. Ornish's study will help to change the attitudes of cardiologists if he can continue to show that coronary heart disease can melt away,'' Dr. Leaf said. ''Now more cardiologists may be willing to do some preventive medicine instead of waiting to do a coronary bypass.''