Therapy's Mettle to Be Tested
(HealthScoutNews) -- Much like tattoos and body piercing, chelation
therapy may be poised to move from the margins of medicine into
The National Center for Complementary and Alternative Medicine
and the National Heart, Lung, and Blood Institute, both part of
the National Institutes of Health (NIH), are launching the first
large-scale clinical trial to see if chelation therapy is a safe
and effective treatment for people with coronary artery disease,
the leading cause of death for both men and women in the United
Chelation therapy was originally developed in the 1930s to combat
heavy metals such as arsenic, which were expected to be used in
chemical warfare. Patients receive EDTA (ethylene diamine tetra-acetic
acid), a synthetic amino acid, intravenously. The EDTA then binds
to the molecules of the metal in the blood, and the two are expelled
from the body in the urine.
"Arsenic warfare" never materialized, but chelation
therapy has been FDA -approved to treat lead poisoning and other
heavy-metal toxicities. According to the NIH, more than 800,000
patient visits were made for chelation therapy in the United States
in 1997. Cost ranges for the course of therapy run between $2,000
While chelation therapy was being used for metal toxicities,
a number of clinicians noticed some patients with heart disease
and angina seemed to be improving as well. Word spread, and chelation
therapy became a common, off-label procedure for people with angina,
atherosclerosis and other conditions in the 1960s and 1970s.
Then, various small studies appeared to discredit the technique,
and mainstream cardiology moved away from the treatment.
Alternative medicine practitioners, however, stuck with it.
"Chelation, or EDTA, became almost an underground movement
in medicine and cardiology," says Dr. Gervasio A. Lamas,
director of cardiovascular research and academic affairs at Mount
Sinai Medical Center and Miami Heart Institute. Lamas heads up
the current NIH study.
Scientists now feel the earlier studies were not conclusive.
Meanwhile, a spate of more recent studies has renewed interest
in chelation therapy, though these are also largely inconclusive.
There are still, however, thousands of case reports testifying
to chelation therapy's success with cardiovascular disease.
The NIH study intends to settle the matter once and for all.
Study leaders have lined up a list of heavy-hitting medical
institutions such as Brigham and Women's Hospital in Boston and
Duke Clinical Research Institute to participate.
"For me to be able to gather the team we have on this,
I think that's really a sea change," Lamas says. "People
are really interested in settling this question."
"I was very pleased to see that the NIH is going to support
a very large-scale study to answer the question once and for all.
I think it's very important to do this work," says Dr. Woodson
Merrell, executive director of the Continuum Center for Health
and Healing at Beth Israel Medical Center in New York City.
"If it shows that chelation does work, then that would
certainly add something to our armamentarium. If it shows it doesn't
work, then people spending a lot of money could better spend it
elsewhere," Merrell adds.
The trial, scheduled to last five years and to be carried out
at 100 sites, will involve 2,372 patients, all 50 years or older,
who have had a heart attack. People will be randomly assigned
to receive either a standardized chelation solution or a placebo.
Each group will also be randomly assigned to receive high-dose
or low-dose vitamin/mineral supplements.
The chelation therapy will be administered by IV over about
three hours, first once a week and then afterwards every other
month for a total of about 40 infusions; rare side effects, if
it's given too fast, can include cramping in the arms or jaw or
The researchers will be looking to see if the patients suffer
additional heart attacks, stroke, hospitalization for angina,
coronary revascularization or death.
The study is not specifically intended to ferret out why
chelation therapy works -- only if it works.
Nevertheless, Lamas and other scientists have some theories.
One hypothesis holds that EDTA may reduce oxidized LDL, or "bad,"
cholesterol in the blood. Oxidized LDL is extremely toxic.
Another explanation is that EDTA may bind with calcium from
the fatty plaques that block arteries and lead to coronary artery
"I honestly don't know what mechanism it is. And from my
past experiences of looking at the mechanisms of cardiovascular
therapies, it's often what you expect least," Lamas says.
"We're embarking on a large trial without knowing which one
it is and, at end of it all, we may have a therapy that works
and we will then have to retrace our steps and figure out why."
At the very least, clinicians should have an answer.
"We just don't have a comfort level now whether it works
or doesn't work," Merrell says. "It'll be really good
What To Do
Patient enrollment for the NIH trial does not start until March
2003, but interested individuals should call 305-674-2162.
For more information on the upcoming trial, visit the
National Center for Complementary and Alternative Medicine.
For more details about chelation therapy, visit the
American Heart Association, which does not approve of the
process for heart ailments.
Reference Source 101