Chelation Clinics

Chelation Clinics

-===- --111111. CHEST ~~~~NUMBER Chelation Clinics An Abuse of the Physician's Freedom of Choice The Food and Drug Administration is authorized by Co...

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--111111. CHEST ~~~~NUMBER Chelation Clinics An Abuse of the Physician's Freedom of Choice The Food and Drug Administration is authorized by Congress to regulate how manufacturers promote a product, but not how a physician prescribes it. The medical-legal point ofview is that it is only necessary to establish if a given practice meets the standard of care for the community. These precepts provide maximum flexibility for the clinician to prescribe effective and safe medications without prior approval from the FDA. Of course this freedom should be based upon evidence published in scientific peer review journals documenting the validity of such prescribing patterns. Hence, the establishment of sound standards of care is fundamentally related to and dependent upon data obtained from carefully designed clinical trials. The admirable flexibility provided by these regulations can be exploited by naive or avaricious segments of the medical community. We have observed the tragic consequences ofthe misuse offreedom ofchoice as witness recent episodes of therapeutic fads such as laetrile, bizarre dietary programs, and endocrinologic manipulation for "male rejuvenation." One of the most dangerous medical-social phenomena in recent years has been the appearance of "chelation clinics" for the treatment of cardiac and peripheral vascular disease. The American Heart Association, the National Institutes of Health, the Food and Drug Administration, the American Medical Association, the American College of Cardiology, and the American College of Physicians agree that such therapy is of no proven benefit in the treatment of atherosclerosis. Not only is efficacy unproven, but there is great potential danger to such treatment. The distinguished Medical Letter concluded that "there is no acceptable evidence that chelation therapy with EDTA is effective in the treatment of atherosclerosis and the adverse effects of this drug can be lethal." Evidence concerning chelating drugs comes entirely from uncontrolled studies. One of the most revealing aspects of this current phenomenon is that the Food and Drug Administration has never received an IND (Investigational New Drug) form identifying

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the interest of investigators to carry out well controlled studies. No party has ever provided the FDA with an organized submission attempting to show that EDTA is effective therapy for atherosclerosis. The drug companies which manufacture this compound (for use in disease states other than atherosclerosis) have so little faith in the potential for its use in cardiovascular disease that they have not funded clinical studies to test such efficacy. Indeed, why would they? Dr. Peter L. Frommer, Deputy Director of the National Heart, Lung, and Blood Institute, has noted that neither the fundamental rationale for chelation nor the anecdotal clinical results to date have apparently provided an impetus for real clinical investigation. No scientifically valid fundamental reason has been offered why it (chelation therapy) should work. In the majority of patients with arteriosclerosis, calcium deposits are an insignificant part ofthe total lesion. It's predominantly a fibrous overgrowth which would be left behind even if the calcium were removed and would be more than enough to cause trouble. And beSides, when calcium in the blood is chelated. why would it be replenished from these inaccessible bits of calcium rather than from the accessible relatively large stores of calcium in bone?

Not a single reputable cardiovascular society in the world endorses chelation therapy for the treatment of atherosclerosis. No scientific clinical trials demonstrating efficacy have been published in a reputable medical journal! With such overwhelming and damning evidence that chelation therapy should be used only on an investigational basis, how is it that some physicians treat patients with this expensive and hazardous agent? An astute analysis of how such "therapeutic adventurism" can occur was described recently by Scott of New Zealand. 2 He noted while orthodox science and medicine are restricted to the laws oflogic and the dictates ofcontrolled observation. those promoting fringe medicine and the pseudo-sciences operate through the media with no such restrictions. One of their most effective weapons is to manoeuvre medical science into a position where orthodoxy has to disprove the claims of fringe medicine, rather than having fringe medicine proponents establish their own credibility.

Scott concludes that, "The onus lies upon the supporters of chelation to prepare a protocol which will withstand independent scrutiny, to provide the finance for such a trial, and to ensure that there is independent evaluation of the results."2 "Anyone who accepts chelation therapy is automatically a 'guinea pig,' "3 and since the treatments have not CHEST I 86 12 I AUGUST, 1984

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been given as part of carefully controlled trials, "he or she is a guinea pig without a purpose, as no useful information is going to be obtained." Responsible clinicians throughout the world agree with the assessment published in lAMA that "chelation therapy has not been established as an acceptable treatment for coronary or other arterial atherosclerosis."'In the face of this evidence the clinician who in 1984 recommends chelating drugs for the treatment of vascular disease is abusing a precious freedom. This freedom is a privilege that has been granted physicians for uses vastly different from the establishment of chelation clinicsl Chelation therapy for atherosclerosis does not meet the standards ofacceptable medical care ror any community in the United States or any other country in the world.

Alfred Soffer, M.D., F.C.C.P. Park Ridge, Illinois

REFERENCES 1 EDTA chelation therapy for arteriosclerotic heart disease. Med

Lett Drug Ther 1981; 23:51 2 Scott PJ. Chelation therapy for degenerative vascular disease. N Zealand Med J 1982; 95:538-539 3 Three unproven medical treatments. Harvard Med Lett 1983; 8(pt3):1 4 Diagnostic and Therapeutic Technology Assessment. Chelation therapy (questions and answers). JAMA 1983; 250:672

Bronchoscopic Phototherapy with the Neodymium-VAG Laser The availability of the neodymium-yttrium-aluminum-garnet (neodymium-YAG) laser for human use has added a powerful tool for the treatment of airway obstruction. The neodymium-YAG laset; initially developed for industrial use, has become widely accepted ror use in the respiratory tract because of its unique properties. High power output (up to 100 watts), ability to be transmitted through a flexible quartz monofilament, and poor absorption by hemoglobin make the neodymium-YAG laser more advantageous than the carbon dioxide or argon laseI: In 1982, Dumon et all presented the results of 215 neodymium-YAG laser treatments in ill patients. For these first patients, a flexible fiberoptic bronchoscope was inserted through the nose or through a previously placed rigid bronchoscope. Power levels ranged from 20 to 100 watts; the pulse duration was not specified. No death or serious complication was reported in that series. In this issue of Chest (see page 163), Dumon et al report the results of 1,503 neodymium-YAG laser treatments in 839 patients; the mortality rate was 0.3 percent. These investigators now strongly recommend 158

the use ofa rigid bronchoscope system for all but lowgrade obstructions or lesions occurring peripherally, power levels below 45 watts, and pulse duration of0.5 to 1 second. Their excellent results and low complication rate attest to their skillful technique and careful selection of patients. Their technique appears to have been modified over the years as more patients have completed treatment. The reasons for their evolution in surgical technique and the data to support their conclusions are not clear in their report. Certainly, using the rigid bronchoscope improves the ability to deal with complications and greatly facilitates the mechanical removal oftumor tissue. Low laser power levels (below 50 watts) and short pulses reduce the risk of perforation and penetration to underlying vital structures. In general, therefore, we agree with the recommendations of this group; however, neodymium-YAG laser phototherapy can be done safely with the flexible bronchoscope, also. In 1982, on the basis ofthe original article by Dumon et al, investigators in the United States began using the neodymium-YAG laser with the flexible fiberoptic system. High power outputs (greater than 50 watts) were used in an attempt to vaporize the obstructing tissue. McDougall and Cortesei reported results of their first 28 treatments in 22 patients. In this initial treatment group, two patients died because of uncontrollable hemorrhage in the airways. It became apparent that high power outputs were dangerous. At increasing power outputs, the depth of penetration cannot be controlled and the risk of perforation into a major vessel is increased. Furthermore, the treatment of upper lobe obstructing lesions is hazardous. The difficult problem of selecting the proper path along the bronchial lumen while working around the upper lobe bend increases the risk of perforation through the bronchial wall and into a major vessel. By not treating upper lobe obstructing lesions, by using lower power (less than 50 watts), and by adhering to published criteria, i we have had no major complication in the past year. In essence, by photocoagulating tissue and reducing the risk of hemorrhage, the laser allows safer mechanical removal of lesions in the trachea and main-stem bronchi. Mechanical removal ofobstructing tissue is not ne~ Ever since bronchoscopy has been available, various techniques for mechanical removal or cryotherapy have been tried to relieve ailWay obstructions.' Now that the neodymium-YAG laser reduces the risk of mechanical resection of obstructing tumor tissue from the major airways, the use of the rigid bronchoscope becomes more attractive, not only because ofsafety but also because of efficiency. The rigid bronchoscope can be used itself to shave tissue off bronchial walls. It allows larger biopsy forceps for removal oftissue. Also, by allowing simultaneous suctioning and laser therapy,