TUESDAY, Aug. 27, 2002 (HealthDayNews) -- Angioplasty patients who are given a cocktail of vitamins designed to lower their homocysteine levels get a clear and lasting benefit from the therapy, according to new research.
The amino acid homocysteine is increasingly being viewed as a likely trigger for heart attacks and stroke. And a report in tomorrow's Journal of the American Medical Association says that reducing blood levels of homocysteine offers marked benefits for patients who have angioplasty, the artery-opening procedure.
The new report describes the longer-term results of a 2001 trial in which 272 patients got the vitamin therapy -- folic acid and vitamins B12 and B6 -- and 281 received a placebo for six months following angioplasty.
The hope was that the vitamin treatment would reduce the incidence of restenosis -- closing of the reopened arteries -- and thus reduce the number of heart attacks and deaths.
"We were able to show in our first report last summer that this combination of vitamins reduced the rate of restenosis by 50 percent, more or less, after six months," says the leader of the study group, Dr. Guido Schnyder, an assistant professor of medicine at the University of California, San Diego. "It was rational to do a follow-up study to see whether this reduction in restenosis would decrease the number of deaths, heart attacks and readmissions to the hospital and whether the benefits of the vitamins would last after six months."
"The answers to both questions is 'yes,' " Schnyder adds.
The journal report says that only 15.4 percent of the patients who took the vitamins suffered an "adverse event" -- such as a heart attack -- during a follow-up period averaging 11 months. This compared to 22.8 percent of patients taking the placebo.
This is far from the last word on homocysteine and its link to heart health, says Schnyder.
The definitive word will come from several ongoing studies designed to see whether homocysteine-lowering therapy can reduce the risk of cardiovascular problems, he adds, noting, "In a year or two, these studies will clearly show whether there is a benefit. We would not extrapolate the results of our study to the general population."
Homocysteine is believed to increase the risk of cardiovascular disease by causing an inflammatory attack against the delicate inner lining of the arteries and by stimulating growth of cells that can block the arteries. At present, American Heart Association guidelines do not list it as a risk factor for the general population.
"There is an active process by which the guidelines get revisited," says Dr. Robert Bonow, president of the American Heart Association and a professor of medicine at Northwestern University.
The guidelines might be revised following the conclusion of studies of homocysteine-lowering treatments now under way in the United States, Britain, Australia and Norway, he adds.
One complication before mass screening and treatment could be recommended is that high homocysteine levels are not nearly as common as high cholesterol levels, Bonow says.
"If you go looking for it, you don't find it elevated in most persons, whereas elevated cholesterol is very prevalent," he says. "So for most people, what we recommend is a healthy balanced diet or cereals fortified with folic acid."
"On the other hand, if a person is at higher risk -- someone with a strong family history or other risk factors -- then measuring and treating elevated homocysteine might be good," he adds. "If someone has coronary artery disease at a young age, more intensive care might be warranted."
People with known coronary risk factors should have their homocysteine levels checked, Schnyder agrees. One advantage is that folic acid and vitamin therapy can often handle the problem.
"The treatment is fairly inexpensive, has no side effects and patients love the idea," Schnyder says.
What To Do
You can learn more about homocysteine by visiting this American Heart Association Web site, or American Family Physician.
