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Thursday, July 3, 2008

WHAT IS CHELATION THERAPY AND HOW IT WORKS

Questions and Answers About Chelation Therapy

For more than30 years, people with fatty buildups of plaque in their arteries (atherosclerosis) may have heard about a “miracle cure” called chelation (pronounced “ke-LA'shun”) therapy. But you may not know that the American Heart Association and other medical and scientific groups have spoken out against this treatment.

This answers the most frequently asked questions about chelation therapy. It also gives the American Heart Association’s position on this procedure, as well as those of other highly regarded scientific organizations.

What’s atherosclerosis?

Atherosclerosis is also called “hardening of the arteries.” It occurs when the inner walls of the arteries become lined with deposits of fat, cholesterol and other substances, including calcium. This fatty buildup usually starts early in life and gradually gets worse over many years. That’s why middle-aged and older people are more likely to have the disease.

As plaque builds up, the arteries become hard and constricted. They lose their ability to expand and contract as blood flows through them and they get narrower. These changes make it harder for blood to flow through them, so the heart must work harder to pump blood throughout the body.

If this plaque ruptures or a blood clot blocks a narrowed artery, a heart attack, stroke or other serious medical problem can result. A heart attack happens when an artery bringing blood to the heart muscle is blocked. A stroke occurs when an artery to the brain is blocked.

What’s chelation therapy?

Chelation therapy is administering a man-made amino acid called EDTA into the veins. (EDTA is an abbreviation for ethylenediamine tetraacetic acid. It’s marketed under several names, including Edetate, Disodium, Endrate, and Sodium Versenate.) EDTA is most often used in cases of heavy metal poisoning (lead or mercury). That’s because it can latch onto or bind these metals, creating a compound that can be excreted in the urine.

Besides binding heavy metals, EDTA also “chelates” (naturally seeks out and binds) calcium, one of the components of atherosclerotic plaque. In the early 1960s, this led to speculation that EDTA could remove calcium deposits from buildups in arteries. The idea was that once the calcium was removed by regular treatments of EDTA, the remaining elements in the plaque would break up and the plaque would clear away. The narrowed arteries would be restored to their former state.

Based upon this thinking, chelation therapy has been proposed to treat existing atherosclerosis and to prevent it from forming.

After carefully reviewing all the available scientific literature on this subject, the American Heart Association has concluded that the benefits claimed for this form of therapy aren’t scientifically proven. That’s why we don’t recommend this type of treatment.

How long does chelation therapy last and how much does it cost?

A single chelation treatment usually lasts from two to four hours and costs between $50 and $100. In the first month, patients usually receive from five to 30 treatments (with 30 being most common). Patients often are advised to continue preventive treatment once a month.

Patients must pay for this treatment themselves. EDTA isn’t a medically accepted procedure for atherosclerosis, so insurance companies and Medicare won’t reimburse for it.

Is there any proof that chelation therapy works?

Supporters of chelation therapy rely on the testimonies of people who’ve had it done. Many people claim that their lives were saved and their health improved because of chelation therapy.

But these aren’t the only claims. Supporters also claim that chelation therapy significantly improves blood flow through previously narrowed blood vessels in some patients. Another claim is that chelation therapy has restored lost bodily function and reduced pain in some cases.

The American Heart Association can’t say why some people feel better after having chelation therapy. And we don’t deny that some people actually may feel better after treatment. So what’s the problem?

The problem is, we question whether these patients feel better because of chelation therapy. It’s possible they feel better because of something else.

For example, chelation therapists usually require their patients to make lifestyle changes. This can include quitting smoking, losing weight, eating more fruits and vegetables, avoiding foods high in saturated fats and exercising regularly. These are healthy changes for anyone to make, and patients make them at the same time that they’re undergoing chelation therapy. That’s what clouds the issue. Research has shown that these  lifestyle changes improve patients’ quality of life and sense of well-being. In fact, we have advocated these lifestyle changes for many years.

The American Heart Association believes that these lifestyle changes are probably why the condition of some patients improves. We believe they don’t feel better because of chelation therapy with EDTA, but because of better, healthier habits that they adopt.

Patients also may feel better for psychological reasons. Sometimes a sick person’s symptoms disappear for no apparent reason, due to a placebo effect. This could be why some patients report that they feel better after they’ve spent $3,000 to $5,000 for chelation therapy.

Can chelation therapy be dangerous?

EDTA isn’t totally safe as a drug. There’s a real danger of kidney failure. (renal tubular necrosis). EDTA can also cause bone marrow depression, shock, low blood pressure (hypotension), convulsions, disturbances of regular heart rhythm (cardiac arrhythmias), allergic-type reactions and respiratory arrest.   

In fact, a number of deaths in the United States have been linked with chelation therapy. Also, some people are on dialysis because of kidney failure caused, at least in part, by chelation therapy.

The American Heart Association is concerned that some people who rely on this therapy may delay undergoing proven therapies like drugs or surgery until it’s too late. This is the added danger of relying on an unproven “miracle cure.”

Clearly, people who choose chelation therapy are risking more than money.

What kind of scientific experiment or study is needed to validate (or invalidate) chelation therapy?

The best way to study chelation therapy would be to conduct a two-part study.

  • Step one would be a study that proves EDTA can remove calcium from arterial plaque (and that the plaque. dissolves). The study should also show that this occurs without dangerous side effects.
  • Step two would be properly controlled clinical trials in a large population. This would only be done if EDTA had been proven successful in reducing arterial plaque without dangerous side effects.

What’s a properly controlled clinical trial?

A properly controlled clinical trial meets these criteria:

  • The patients or subjects receiving the treatment formally agree to participate, based upon reliable information given to them by the scientists conducting the trial. The patients would be told of the known risks involved and the possible (but unproven) benefits. Participants would have to give their “informed consent” to participate.
  • The treatments are free to the patients or subjects.
  • The trial is closely monitored and reviewed by 1) knowledgeable scientists who aren’t involved in the trial, 2) representatives of the lay community, 3) representatives of the religious community, 4) statisticians and 5) other interested persons.
  • The trial is “double blind.” This means that neither the patient nor the physician giving the treatment knows whether the patient is getting EDTA or a neutral control substance (placebo). Other precautions to ensure objectivity are 1) that the physician giving the treatment can’t be the person who records the results and 2) the person observing the results can’t know which substance a person under observation received.

Any study that doesn’t follow this methodology will produce results open to question because the process lacks scientific safeguards. Accordingly, the results wouldn’t be scientifically valid. To the knowledge of the American Heart Association, no study of chelation therapy that rigorously follows accepted scientific methodology has ever been completed.

Why hasn’t the American Heart Association funded a project to research this question?

A scientifically valid trial would be very expensive. Also, according to qualified scientists who are familiar with research in heart disease, there’s only a very small chance that chelation therapy will work.

Have scientists ever done a study on chelation therapy?

In the 1960s scientists started a small-scale study involving 30 patients. However, after two patients died and the others showed no signs of improvement, it was stopped.

Also, a recent study of chelation therapy, using currently approved scientific methodology, was done on people with intermittent claudication. (This is peripheral artery disease [fatty buildups] in leg arteries.) This study found that EDTA chelation therapy was no more effective than a placebo (sugar pill).

Finally, a recent study entitled “Chelation therapy for ischemic heart disease” was published in the Journal of the American Medical Association (JAMA 2002;287:481-486). The authors followed 84 patients for 27 weeks. All of the patients had coronary artery disease. One-half of the patients received intravenous chelation therapy during the study period and the other one-half received intravenous placebo (fluid with no drug). Neither the physicians nor the patients knew whether they were receiving chelation or placebo. Patients were given exercise tests to see how long they could exercise before their electrocardiogram (ECG) showed changes indicating ischemia. They also answered quality-of-life questionnaires. At the end of the 27 weeks, the patients who received chelation were no better than the patients who received placebo. The authors concluded that “Based on exercise time to ischemia, exercise capacity and quality-of-life measurements, there is no evidence to support a beneficial effect of chelation therapy in patients with ischemic heart disease, stable angina, and a positive treadmill test for ischemia.”

Thus, there’s still no scientific evidence that demonstrates any benefit from chelation therapy.

What’s the American Heart Association’s position?

We have a task force that examines the medical support for new and unestablished therapies, of which chelation is one. The report of the task force was adopted by the American Heart Association as our official policy statement on chelation therapy. This report states:

The American Heart Association’s Clinical Science Committee has reviewed the available literature on the use of chelation (EDTA) in the treatment of arteriosclerotic heart or blood vessel disease and finds no scientific evidence to demonstrate any benefit of this form of therapy. Furthermore, employment of this form of unproven treatment may deprive patients of the well-established benefits attendant to the many other valuable methods of treating these diseases.

What do other authorities say about this treatment?

Food and Drug Administration:

In the absence of evidence of safety and effectiveness, the use of this treatment for atherosclerosis is investigational. To date, no physician or sponsor has filed a plan or protocol to study its (EDTA’s) use in such treatment.

No party has ever provided us with an organized submission attempting to show that it is an effective therapy in atherosclerosis; instead, we have been handed unorganized data without any attempt to describe a formal study.

Under the circumstances, we have had no choice but to attempt to prevent improper promotion of the drug and to point out its unproven status.

American College of Physicians:

Chelation therapy with EDTA has been used in the treatment and prevention of atherosclerosis. Because of the risk of severe renal (kidney) toxicity and lack of objective evidence suggesting therapeutic benefit from EDTA therapy … such therapy should be regarded as investigational and (should be) conducted under carefully controlled conditions in an academic institution by experienced investigators.

National Heart, Lung, and Blood Institute, National Institutes of Health:

There is no reason to expect benefit from chelation in the management of arteriosclerosis. More importantly, there has been no scientific evidence of such benefit — and there is scientific evidence of no benefit.

American Medical Association:

The AMA believes that chelation therapy for atherosclerosis is an experimental process without proven efficacy. They have also reaffirmed their 1984 House of Delegates Resolution stating:

“…there is no scientific documentation that the use of chelation therapy is effective in the treatment of cardiovascular disease, atherosclerosis, rheumatoid arthritis, and cancer;

“…if chelation therapy is to be considered a useful medical treatment for anything other than heavy metal poisoning, hypercalcemia, or digitalis toxicity, it is the responsibility of its proponents to (a) conduct properly controlled scientific studies, (b) adhere to Food and Drug Administration (FDA) guidelines for the investigation of drugs, and (c) disseminate results of scientific studies in the usually accepted channels.

American College of Cardiology:

There is insufficient scientific evidence to justify the application of chelation therapy for atherosclerosis on a clinical basis. At the present time, therefore, chelation therapy should be applied only under an investigational protocol.

Isn’t it true that practicing physicians and medical organizations oppose chelation therapy because widespread use of this procedure would mean a loss of income to cardiovascular specialists, particularly surgeons?

No. Organized medicine opposes chelation therapy because it’s an unproven procedure and it involves extreme risks to patients who receive it.

The truth is that physicians who treat cardiovascular diseases could significantly increase their income if chelation therapy was a scientifically proven treatment procedure. Many people have atherosclerosis, but only a relatively small percentage develop problems severe enough to require surgery. If chelation were scientifically proven, EDTA could be administered to everyone who had atherosclerosis. Surgery can be done on only one patient at a time. With chelation, the number of patients who can be treated is limited only by the amount of room in the practitioner’s office.

 

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