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Chelation therapy

 
Alternative Medicine Encyclopedia: Chelation Therapy
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Definition

Chelation therapy is an intravenous treatment designed to bind heavy metals in the body in order to treat heavy metal toxicity. Proponents claim it also treats coronary artery disease and other illnesses that may be linked to damage from free radicals (reactive molecules).

Origins

The term chelation is from the Greek root word "chele," meaning "claw." Chelating agents, most commonly diamine tetraacetic acid (EDTA), were originally designed for industrial applications in the early 1900s. It was not until the World War II era that the potential for medical therapy was realized. The initial intent was to develop antidotes to poison gas and radioactive contaminants. The need for widespread therapy of this nature did not materialize, but more practical uses were found for chelation. During the following decade, EDTA chelation therapy became standard treatment for people suffering from lead poisoning. Patients who had received this treatment claimed to have other health improvements that could not be attributed to the lead removal only. Especially notable were comments from those who had previously suffered from intermittent claudication and angina. They reported suffering less pain and fatigue, with improved endurance, after chelation therapy. These reports stimulated further interest in the potential benefits of chelation therapy for people suffering from atherosclerosis and coronary artery disease.

Benefits

The benefits of EDTA chelation for the treatment of lead poisoning and excessively high calcium levels are undisputed. The claims of benefits for those suffering from atherosclerosis, coronary artery disease, and other degenerative diseases are more difficult to prove. Reported uses for chelation therapy include treatment of angina, gangrene, arthritis, multiple sclerosis, Parkinson'sdisease, psoriasis, and Alzheimer's disease. Improvement is also claimed for people experiencing diminished sight, hearing, smell, coordination, and sexual potency.

Description

If the preparatory examination suggests that there is a condition that could be improved by chelation therapy, and there is no health reason why it shouldn't be used, then the treatment can begin. The patient is generally taken to a comfortable treatment area, sometimes in a group location, and an intravenous line is started. A solution of EDTA together with vitamins and minerals tailored for the individual patient is given. Most treatments take three to four hours, as the infusion must be given slowly in order to be safe. The number of recommended treatments is usually between 20 and 40. They are given one to three times a week. Maintenance treatments can then be given at the rate of once or twice a month. Maximum benefits are reportedly attained after approximately three months after a treatment series. The cost of therapy is considerable, but it is a fraction of the cost of an expensive medical procedure like cardiac bypass surgery. Intravenous vitamin C and mercury chelation therapies are also offered.

Preparations

A candidate for chelation therapy should initially have a thorough history and physical to define the type and extent of clinical problems. Laboratory tests will be done to determine whether there are any conditions present that may prevent the use of chelation. Patients who have preexisting hypocalcemia, poor liver or kidney function, congestive heart failure, hypoglycemia, tuberculosis, clotting problems, or potentially allergic conditions are at higher risk for complications from chelation therapy. A Doppler ultrasound may be performed to determine the adequacy of blood flow in different regions of the body.

Precautions

It is important for people who receive chelation therapy to work with medical personnel who are experienced in the use of this treatment. Treatment should not be undertaken before a good physical, lifestyle evaluation, history, and any laboratory tests necessary are performed. The staff must be forthcoming about test results and should answer any questions the patient may have. Evaluation and treatment should be individualized and involve assessment of kidney function before each treatment with chelation, since the metals bound by the EDTA are excreted through the kidneys.

Although EDTA binds harmful, toxic metals like mercury, lead, and cadmium, it also binds some essential nutrients of the body, such as copper, iron, calcium, zinc, and magnesium. Large amounts of zinc are lost during chelation. Zinc deficiency can cause impaired immune function and other harmful effects. Supplements of zinc are generally given to patients undergoing chelation, but it is not known whether this is adequate to prevent deficiency. Also, chelation therapy does not replace proper nutrition, exercise, and appropriate medications or surgery for specific diseases or conditions.

Side Effects

Side effects of chelation therapy are reportedly unusual, but are occasionally serious. Mild reactions may include, but are not limited to, local irritation at the infusion site, skin reactions, nausea, headache, dizziness, hypoglycemia, fever, leg cramps, or loose bowel movements. Some of the more serious complications reported have included hypocalcemia, kidney damage, decreased clotting ability, anemia, bone marrow damage, insulin shock, thrombophlebitis with embolism, and even rare deaths. However, some doctors feel that the latter groups of complications occurred before the safer method currently used for chelation therapy was developed.

Research & General Acceptance

EDTA chelation is a highly controversial therapy. The treatment is approved by the United States Food and Drug Administration (FDA) for lead poisoning and seriously high calcium levels. However, for the treatment of atherosclerotic heart disease, EDTA chelation therapy is not endorsed by the American Heart Association (AHA), the FDA, the National Institutes of Health (NIH), or the American College of Cardiology. The AHA reports that there are no adequate, controlled, published scientific studies using currently approved scientific methods to support this therapy for the treatment of coronary artery disease. However, a pooled analysis from the results of more than 70 studies showed positive results in all but one. And in 2002, the American College of Advancement in Medicine pledged its full support to a $30 million federal study aimed at determining the safety and efficacy of chelation therapy in patients with heart disease. The five-year clinical trial involves more than 2,000 people at about 100 sites around the country.

Training & Certification

The American Board of Chelation Therapy (ABCT) provides minimum standards for members administering chelation. Diplomates have passed written and oral tests and received supervision of treatment in order to receive certification.

One professional group that makes recommendations for treatment methods is the American College for Advancement in Medicine (ACAM). If contacted, the organization will mail out a directory of doctors who are members and follow their methods. ACAM also offers chelation therapy workshops.

Resources

Books

Cassileth, Barrie. The Alternative Medicine Handbook. New York: W. W. Norton & Company, Inc., 1998.

Cranton, Elmer. Bypassing Bypass. Virginia: Medex Publishers, Inc., 1997.

Periodicals

Chappel, Stall. Journal of the Advancement of Medicine 6 (1993): 139-160.

"Physician Group Backs New NIH Chelation Therapy Study for Heart Disease." Heart Disease Weekly (September 29, 2002):13.

Organizations

The American College for Advancement in Medicine (ACAM). 23121 Verdugo Dr., Suite 204, Laguna Hills, CA 92653. (714) 583-7666.

American Heart Association. http://www.americanheart.org/Heart_and_Stroke_A_Z_Guide/chelat.html. 2000.

Other

Cranton, Elmer. Chelation therapy. http://www.drcranton.com/chelation.html. 1999.

Green, Saul. Quackwatch: Chelation therapy. http://www.quackwatch.com/01QuackeryRelatedTopics/chelation.html. 2000.

[Article by: Judith Turner; Teresa G. Odle]

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Wikipedia: Chelation therapy
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Chelation therapy is the administration of chelating agents to remove heavy metals from the body. For the most common forms of heavy metal intoxication—those involving lead, arsenic or mercury—the standard of care in the USA dictates the use of dimercaptosuccinic acid (DMSA).[citation needed] Other chelating agents, such as 2,3-dimercapto-1-propanesulfonic acid (DMPS) and alpha lipoic acid (ALA), are used in conventional and alternative medicine.

Contents

History

Chelating agents were introduced into medicine as a result of the use of poison gas in World War I. The first widely used chelating agent, the organic dithiol compound dimercaprol (also named British Anti-Lewisite or BAL), was used as an antidote to the arsenic-based poison gas, Lewisite. The sulphur atoms in BAL's mercaptan groups strongly bond to the arsenic in Lewisite, forming a water-soluble compound that entered the bloodstream, allowing it to be removed from the body by the kidneys and liver. BAL had severe side-effects.

After World War II, a large number of navy personnel suffered from lead poisoning as a result of their jobs repainting the hulls of ships. The medical use of EDTA as a lead chelating agent was introduced. Unlike BAL, it is a synthetic amino acid and contains no mercaptans. EDTA side effects were not considered as severe as BAL.

In the 1960s, BAL was modified into DMSA, a related dithiol with far fewer side effects. DMSA quickly replaced both BAL and EDTA, becoming the US standard of care for the treatment of lead, arsenic, and mercury poisoning, which it remains today.

Research in the former Soviet Union led to the introduction of DMPS, another dithiol, as a mercury-chelating agent. The Soviets also introduced ALA, which is transformed by the body into the dithiol dihydrolipoic acid, a mercury- and arsenic-chelating agent. DMPS has experimental status in the US FDA, while ALA is a common nutritional supplement.

Since the 1970s, iron chelation therapy has been used as an alternative to regular phlebotomy to treat excess iron stores in people with haemochromatosis.[1]

Other chelating agents have been discovered. They all function by making several chemical bonds with metal ions, thus rendering them much less chemically reactive. The resulting complex is water-soluble, allowing it to enter the bloodstream and be excreted harmlessly.

Calcium-disodium EDTA chelation is approved by the U.S. Food and Drug Administration (FDA) for treating lead poisoning and heavy metal toxicity.[2]

In 1998, the U.S. Federal Trade Commission (FTC) pursued the American College for Advancement in Medicine (ACAM), an organisation that promotes "complementary, alternative and integrative medicine" over their advertising of EDTA chelation therapy, with claims including "Chelation therapy is a safe, effective and relatively inexpensive treatment to restore blood flow in victims of atherosclerosis without surgery." The FTC found that "scientific studies do not prove that EDTA chelation therapy is an effective treatment for atherosclerosis.", and that the statements by the ACAM were false.[3] In 1999, the ACAM agreed to stop misrepresenting chelation therapy as effective in treating heart disease, avoiding legal proceedings.[4][5]

Medical use

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Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. (February 2008)
Two molecules of deferasirox, an orally administered chelator, binding iron. Deferasirox is used in the treatment of transfusional iron overload in people with thalassemia.

Chelation therapy is used as a treatment for acute mercury, iron (including in cases of thalassemia), arsenic, lead, uranium, plutonium and other forms of toxic metal poisoning. The chelating agent may be administered intravenously, intramuscularly, or orally, depending on the agent and the type of poisoning. [6]

One example of successful chelation therapy is the case of Harold McCluskey, a nuclear worker who became badly contaminated with americium in 1976. He was treated with diethylene triamine pentaacetic acid (DTPA) over many years, removing 41 MBq (1.1 mCi) of americium from his body. His death, 11 years later, was from unrelated causes.

Several chelating agents are available, having different affinities for different metals. Common chelating agents include:

Medically diagnosed heavy metal poisoning

Chelation therapy was used by the British after World War II to remove arsenic, lead, and other metals. Patients' conditions improved as these metals were removed from their bodies.[7] Treatment may be applied to the skin via a transdermal patch.[8] Another treatment is administered intravenously, a process that takes 2–3 hours, costs about $100 per treatment, and 20-30 treatments are often required.[9]

Some common chelating agents are EDTA (ethylenediaminetetraacetic acid), DMPS (2,3-dimercaptopropanesulfonic acid), TTFD (thiamine tetrahydrofurfuryl disulfide), and DMSA (2,3-dimercaptosuccinic acid). Calcium-disodium EDTA and DMSA are only approved for the removal of lead by the Food and Drug Administration while DMPS and TTFD are not approved by the FDA. These drugs bind to heavy metals in the body and prevent them from binding to other agents. They are then excreted from the body. The chelating process also removes vital nutrients such as vitamins C and E, therefore these must be supplemented.[10]

Use in alternative medicine

Alternative medicine uses chelation therapy as a non-standard treatment for some ailments, including heart disease and autism.[11][12] Attempts have been made to use it in treating kidney dysfunction, calcific band keratopathy (an eye disorder), and ovarian cancer.[13] Currently there is a US National Center for Complementary and Alternative Medicine (NCCAM) trial being conducted on the chelation therapy's safety and efficacy for patients with coronary artery disease.[14] NCCAM Director Stephen E. Straus cited the "widespread use of chelation therapy in lieu of established therapies, the lack of adequate prior research to verify its safety and effectiveness, and the overall impact of coronary artery disease" as factors motivating the trial.[15] The proposed study has been criticized as unnecessary and possibly dangerous.[16]

Heart disease

Some alternative medicine practitioners administer chelating agents, usually EDTA, to patients with hardening of the arteries. The use of EDTA chelation therapy as a treatment for coronary artery disease has not been shown to be effective and is not approved by the U.S. Food and Drug Administration (FDA).[17] Several possible mechanisms have been proposed, though none have been scientifically validated. The procedure might leach calcium directly from the fatty plaques that block the arteries; stimulate the release of a hormone that removes deposited calcium or lowers cholesterol levels; or reduce oxidative stress on the blood vessel walls.[2] The US National Center for Complementary and Alternative Medicine began conducting the Trial to Assess Chelation Therapy (TACT) in 2003.[14] Patient enrollment was to be completed around July 2009[2] with final completion around July 2010,[14] but enrollment in the trial was suspended on September 26, 2008 for an investigation by OHRP after complaints about ethical concerns such as inadequate informed consent.[18] The trial has been criticized for lacking prior Phase I and II studies, and particularly because previous controlled trials have not indicated benefits.[16] The American College for Advancement in Medicine, a controversial organization created to promote chelation therapy, has played a part in the adoption of the TACT clinical trial, which has led to further criticism of the trial.[16] Atwood et al. have argued that methodological flaws and lack of prior probability make this trial "unethical, dangerous, pointless, and wasteful."[16]

The American Heart Association states that there is "no scientific evidence to demonstrate any benefit from this form of therapy" and that the "United States Food and Drug Administration (FDA), the National Institutes of Health (NIH) and the American College of Cardiology all agree with the American Heart Association" that "there have been no adequate, controlled, published scientific studies using currently approved scientific methodology to support this therapy for cardiovascular disease."[17] Like other scientific commentators, they note that any improvement among heart patients undergoing chelation therapy can be attributed to the placebo effect and lifestyle changes discovered in conventional medicine but recommended by chelationists; "quitting smoking, losing weight, eating more fruits and vegetables, avoiding foods high in saturated fats and exercising regularly".[19] They note their concern that patients could put off proven treatments for heart disease like drugs or surgery.[19] A 2005 systematic review found that controlled scientific studies did not support chelation therapy for heart disease.[20] It found that very small trials and uncontrolled descriptive studies have reported benefits while larger controlled studies have found results no better than placebo

Autism

Main article: Thiomersal controversy

Based on speculation that mercury poisoning may trigger the symptoms of autism,[21] chelation therapy is widely used to treat autism, with some surveys suggesting 2–8% of children with autism have had the therapy. Parents either have a doctor use a treatment for lead poisoning, or buy unregulated supplements.[22] Aspies For Freedom, an autistic rights organization, considers this use of chelation therapy unethical and potentially dangerous.[23] There is strong epidemiological evidence that refutes links between environmental triggers, in particular thimerosal-containing vaccines, and the onset of autistic symptoms.[24][25][26][27] There is no scientific support for chelation therapy as a treatment for autism.[12][28]

Controversy

The efficacy, safety, and much of the theory behind these alternative practices are disputed by the medical community. In 2001, researchers at the University of Calgary reported that cardiac patients receiving chelation therapy fared no better than those who received placebo treatment.[29]

In 1998, the U.S. Federal Trade Commission (FTC) charged that the web site of the American College for Advancement in Medicine (ACAM) and a brochure they published had made false or unsubstantiated claims. In December 1998, the FTC announced that it had secured a consent agreement barring ACAM from making unsubstantiated advertising claims that chelation therapy is effective against atherosclerosis or any other disease of the circulatory system.[30][31]

Prevalence

The American College for Advancement in Medicine, which promotes chelation therapy, estimates that 800,000 patient visits for chelation therapy were made in the United States in 1997.[32]

Side effects and safety concerns

There is a low occurrence of side effects when chelation is used at the dose and infusion rates approved by the U.S. FDA as a treatment for heavy metal poisoning. A burning sensation at the site of delivery into the vein is common. Other side effects include fever, headache, nausea, stomach upset, vomiting, convulsions, bone marrow depression (dropping blood cell counts), a drop in blood pressure, cardiac arrhythmias, respiratory arrest, and hypocalcemia. Other concerns include kidney failure, which can require permanent life-limiting and expensive dialysis, or cause death.[19]

2007 research with lab rats indicates giving chelating agent DMSA to rats without high levels of lead may cause lasting cognitive damage. [33]

When EDTA is not administered by a health professional for the treatment of heavy metal poisoning more serious side effects can occur.[2]

Chelation therapy can be hazardous, even conducted with the FDA-approved chelation agents. In August 2005, botched chelation therapy conducted by an ACAM member killed a 5-year-old autistic boy,[16] a 3-year-old nonautistic girl died in February 2005, and a nonautistic adult died in August 2003. These deaths were due to cardiac arrest caused by hypocalcemia during chelation therapy.[34] Only the 3-year-old girl had been medically assessed and found to have an elevated blood lead level and resulting low iron levels and anemia, a proper medical cause for chelation therapy to be conducted.[35]

More than 30 deaths have been recorded in association with IV-administered disodium EDTA since the 1970s.[16]

References

  1. ^ "Hemochromatosis: Monitoring and Treatment". National Center on Birth Defects and Developmental Disabilities (NCBDDD). 2007-11-01. http://www.cdc.gov/ncbddd/hemochromatosis/training/treatment/monitoring_treatment.htm. Retrieved 2008-03-29. 
  2. ^ a b c d "Questions and Answers: The NIH Trial of EDTA Chelation Therapy for Coronary Artery Disease". National Center for Complementary and Alternative Medicine (NCCAM). http://nccam.nih.gov/news/2002/chelation/q-and-a.htm. Retrieved 2007-11-11. 
  3. ^ http://www.ftc.gov/os/1999/07/9623147c3881acamcmp.htm
  4. ^ http://www.ftc.gov/os/1998/12/9623147agr.htm
  5. ^ http://www.ftc.gov/os/1998/12/9623147att.htm
  6. ^ Natural Standard Professional Monograph. http://www.naturalstandard.com/monographs/monoframeset.asp?monograph=/monographs/alternativemodalities/chelation.asp%3Fprintversion%3Dtrue Accessed June 16, 2009.
  7. ^ Nash, R. A. (2005). Metals in medicine. Alternative Therapies in Health and Medicine , 11 (4), 18-25.
  8. ^ Bridges, S. (2006). The promise of chelation. Mothering , 54-61.
  9. ^ Klotter, J. (2006). Chelation for autism. Townsend Letter: The Examiner of Alternative Medicine , 30, p. 273.
  10. ^ Bridges, S. (2006). The promise of chelation. Mothering , 54-61.
  11. ^ Ernst E (2000). "Chelation therapy for coronary heart disease: An overview of all clinical investigations". Am. Heart J. 140 (1): 139–41. doi:10.1067/mhj.2000.107548. PMID 10874275. 
  12. ^ a b Weber W, Newmark S (2007). "Complementary and alternative medical therapies for attention-deficit/hyperactivity disorder and autism". Pediatr Clin North Am 54 (6): 983–1006. doi:10.1016/j.pcl.2007.09.006. PMID 18061787. 
  13. ^ Natural Standard Bottom Line Drug Monograph: Chelation Therapy. http://www.naturalstandard.com/monographs/alternativemodalities/patient-chelation.asp?printversion=true?printversion=true. Accessed June 16, 2009.
  14. ^ a b c NCCAM.Trial to assess chelation therapy
  15. ^ http://nccam.nih.gov/news/2002/chelation/pressrelease.htm
  16. ^ a b c d e f Atwood KC, Woeckner E, Baratz RS, Sampson WI (2008). "Why the NIH Trial to Assess Chelation Therapy (TACT) should be abandoned". Medscape J Med 10 (5): 115. PMID 18596934. 
  17. ^ a b "American Heart Association: Chelation Therapy". http://www.americanheart.org/presenter.jhtml?identifier=4493. Retrieved 2008-04-03. 
  18. ^ "Government probes chelation-heart disease study". Washington Post (AP). http://www.washingtonpost.com/wp-dyn/content/article/2008/09/25/AR2008092503085.html. Retrieved 2008-09-26. 
  19. ^ a b c http://www.americanheart.org/presenter.jhtml?identifier=3000843
  20. ^ Seely DM, Wu P, Mills EJ (2005). "EDTA chelation therapy for cardiovascular disease: a systematic review". BMC Cardiovasc Disord 5: 32. doi:10.1186/1471-2261-5-32. PMID 16262904. 
  21. ^ Bernard S, Enayati A, Roger H, Binstock T, Redwood L (2002). "The role of mercury in the pathogenesis of autism" (PDF). Mol Psychiatry 7 (Suppl 2): S42–3. doi:10.1038/sj.mp.4001177. PMID 12142947. http://www.nature.com/mp/journal/v7/n2s/pdf/4001177a.pdf. 
  22. ^ Stokstad E (2008). "Stalled trial for autism highlights dilemma of alternative treatments". Science 321 (5887): 326. doi:10.1126/science.321.5887.326. PMID 18635766. 
  23. ^ "Aspies For Freedom". Aspies For Freedom. http://www.aspiesforfreedom.com/. Retrieved 2009-02-24. 
  24. ^ Immunization Safety Review Committee, Board on Health Promotion and Disease Prevention, Institute of Medicine (2004). Immunization Safety Review: Vaccines and Autism. Washington, DC: The National Academies Press. ISBN 0-309-53275-2. http://www.nap.edu/catalog/10997.html. 
  25. ^ Doja A, Roberts W (2006). "Immunizations and autism: a review of the literature". Can J Neurol Sci 33 (4): 341–6. PMID 17168158. 
  26. ^ Thompson WW, Price C, Goodson B et al. (2007). "Early thimerosal exposure and neuropsychological outcomes at 7 to 10 years". N Engl J Med 357 (13): 1281–92. doi:10.1056/NEJMoa071434. PMID 17898097. http://content.nejm.org/cgi/content/full/357/13/1281. 
  27. ^ Rutter M (2005). "Incidence of autism spectrum disorders: changes over time and their meaning". Acta Paediatr 94 (1): 2–15. doi:10.1080/08035250410023124. PMID 15858952. 
  28. ^ Blakeslee, Sandra (2004-05-19). "Panel Finds No Evidence To Tie Autism To Vaccines". New York Times. http://query.nytimes.com/gst/fullpage.html?res=9C02E2D6123FF93AA25756C0A9629C8B63. Retrieved 2008-02-01.  "An examination of scientific studies worldwide has found no convincing evidence that vaccines cause autism, according to a committee of experts appointed by the Institute of Medicine."
  29. ^ Knudtson ML, Wyse DG, Galbraith PD, et al. (2002). "Chelation therapy for ischemic heart disease: a randomized controlled trial". JAMA 287 (4): 481–6. doi:10.1001/jama.287.4.481. PMID 11798370. 
  30. ^ "American College for Advancement in Medicine, File No. 962 3147, Docket No. C-3882". Federal Trade Commission. http://www.ftc.gov/os/caselist/c3882.shtm. Retrieved 2007-11-11. 
  31. ^ "Medical Association Settles False Advertising Charges Over Promotion of 'Chelation Therapy'". Quackwatch. December 8, 1998. http://www.quackwatch.org/02ConsumerProtection/ftcchelation.html. Retrieved 2007-11-11. 
  32. ^ American College for Advancement in Medicine (August 14, 2002). "Physician Group Backs New NIH Chelation Therapy Study For Heart Disease". Press release. http://web.archive.org/web/20070204053351/http://www.acam.org/press_releases/20020814.htm. Retrieved 2007-11-11. 
  33. ^ Succimer Chelation Improves Learning, Attention, and Arousal Regulation in Lead-Exposed Rats but Produces Lasting Cognitive Impairment in the Absence of Lead Exposure
  34. ^ Hazards of chelation therapy:
  35. ^ http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5508a3.htm

External links

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