OREGON STATE UNIVERSITY

Antioxidant vitamins may help transplant patients

04/04/2002

CORVALLIS, Ore. - A new clinical study just published in the medical journal Lancet suggests that people who receive heart transplants, and possibly some other types of transplants or medical procedures, may get important health benefits by taking supplements of both vitamins C and E.

Patients who received supplements of these two antioxidant vitamins had very little coronary arteriosclerosis associated with their transplants. Ordinarily, this is one of the most important limitations to the long-term survival of cardiac transplant recipients - their arteries tend to thicken and clog unusually fast after a transplant, and this disease is present in more than 70 percent of recipients within three years.

The research was done by scientists in the Linus Pauling Institute at Oregon State University and the Cardiovascular Division of Brigham and Women's Hospital in Boston.

Oxidant stress tends to contribute to accelerated coronary arteriosclerosis following a transplant, and the body's natural antioxidant defenses are often reduced. Treatment with antioxidant vitamins appears to have significant value in addressing this problem, the study found.

"Arteriosclerosis is a health condition that's a problem for many people, but it is much more acute and occurs more rapidly in people who have had heart transplants," said Balz Frei, professor and director of the Linus Pauling Institute, and co-author on the study.

This double-blind study was done with 40 heart transplant patients. Half of them received 1,000 milligrams of vitamin C and 800 international units of vitamin E each day. The others received a placebo.

After one year, the study showed that coronary arteries had significantly thickened and narrowed in the group that received a placebo, but were largely unchanged in those who received the antioxidants. The use of antioxidants did not appear to interfere with the immunosuppressive drugs the patients needed to take, or cause any increase in transplant rejection.

Some past studies looking at this and other issues had used vitamin E, by itself, as a supplement, and failed to improve patients' outcomes, the study said. The use of both vitamins C and E in combination appears to work much better, as there may be complementary interactions between the two vitamins which give results different than either one of them would if used separately.

This type of antioxidant therapy may also have value in other types of organ transplants, such as kidney, lung and liver, Frei said, or such medical procedures as angioplasty. Angioplasty is a common medical procedure for patients with coronary artery disease, but one that often has to be repeated within a few months when arteries once again become narrowed.