UnTACTful: the chelation therapy study spin

Big news on chelation therapy, a claimed “detoxification” procedure. $30 million spent on an unethical trial that showed no real effect. But that isn’t going to stop the positive spin.

NIH Trial Gives Surprising Boost To Chelation Therapy

With a result that is likely to surprise and baffle much of the mainstream medical community, a large NIH-sponsored trial has turned up the first substantial evidence in support of chelation therapy for patients with coronary disease. Known as TACT (Trial to Assess Chelation Therapy), the highly controversial trial was presented today at the AHA by Gervasio Lamas. The trial was sponsored by two NIH institutes, the National Center for Complementary and Alternative Medicine and the National Heart Lung and Blood Institute.

Chelation therapy with EDTA to remove heavy metals from the blood in order to treat coronary disease has been around– and provoked criticism– since the 1950s. Despite a lack of evidence and the skepticism of the medical community, passionate supporters have kept the therapy alive in alternative medicine circles.

Now the results of TACT will likely provide ammunition to chelation defenders, but the trial investigators and other experts have expressed considerable caution about the proper interpretation of the results.

But LOOK at the headline!!! If there is considerable caution, why is the headline phrased as if it’s a positive?

Here is the more balanced look.

Chelation therapy doesn’t alter quality of life in heart attack patients.

Chelation therapy didn’t change the ability to perform daily tasks or impact the emotional wellbeing of patients who previously suffered a heart attack, according to late-breaking clinical trial research presented at the American Heart Association’s Scientific Sessions 2012.

There was no impact on patient’s quality of life in this sub-study although the overall Trial to Assess Chelation Therapy (TACT) showed chelation therapy cut the risk of death, second heart attacks, stroke and the need for heart procedures among some patients who already suffered an earlier heart attack.

This quality-of-life study was a planned analysis of 911 randomly chosen patients from the overall trial of chelation therapy, an alternative treatment which uses weekly infusions to remove metals from the bloodstream.

“We didn’t see any effect on the quality of life of chelation therapy patients,” said Daniel B. Mark, M.D., M.P.H., lead author of the sub-study and professor of medicine, director of outcomes research at Duke University Medical Center and Duke Clinical Research Institute in Durham, N.C. “Patients weren’t any worse, but they weren’t any better.

Science based medicine blog announced the results yesterday.

The Trial to Assess Chelation Therapy: Equivocal as Predicted.

It’s ironic, then, that the TACT results are informative in an important way that its authors seem to have overlooked: it convincingly demonstrates that the claims of chelationists have been bogus all along. That’s because those claims have been far more dramatic than even the small effect that the TACT may appear to support. Typically, chelationists, including those involved in the TACT, claim “improvement” or even “marked improvement” in 80-90% of patients with ischemic heart disease or other vascular disease.

Dr. Atwood says, “The TACT was an unethical trial for numerous reasons.” He notes to medical journals editors: “Publishing the Formal TACT Report would Violate your own Ethics” The TACT trial had a misleading consent form and participants were not correctly notified of important risks.

Orac calls chelation theory “pure quackery” and discusses the results of this study which ends what he calls a “long and depressing” story that cost $30 million.

Funny business is an understatement. A complete, unabashed fiasco would be a better description. Or maybe a total and complete waste of taxpayer money. Or perhaps an unethical sham of a trial, perhaps? Whatever you want to call TACT, this concern is quite consistent with worries expressed over six years ago by Dr. R. W. Donnell about the adequacy of the blinding of the trial. In light of such concerns, the differential drop-out rate between the two groups makes a lot more sense. Too bad that Dr. Lamias apparently didn’t see fit to include the relevant information in his press release or in his slide set.

Finally, no study would be complete without a consideration of adverse events. After all, in determining whether a therapy is worth pursuing, it is important to weigh its efficaciousness versus its safety. Overall, 79 adverse events were observed forcing discontinuation of infusions. Reasons included: reaching an endpoint; heart failure; other cardiac issues; GI problems; hematological problems; and a variety of other problems.

This treatment is HIGHLY implausible and did not have the expected positive results. How much MORE money do we waste on additional research through NCCAM on ridiculous ideas? This is sad. And it makes me angry. There have been many calls to kill NCCAM and this OUGHT to be another huge strike against it.

  3 comments for “UnTACTful: the chelation therapy study spin

  1. November 5, 2012 at 12:19 PM

    This is not the first NIH study to be reported recently that has been misrepresented and misreported. That large acupuncture meta analysis was questionably also. I really question the purpose of that institute and its value to the tax payer.

  2. One Eyed Jack
    November 5, 2012 at 1:05 PM

    “The chelation solution contained three grams of the synthetic amino acid ethylene diamine tetra-acetic (EDTA), seven grams of vitamin C, B-vitamins, electrolytes, a local anesthetic and heparin, an anti-clotting drug. The placebo infusion was salt water and a small amount of sugar.”


    What kind of control placebo is this? In addition to EDTA, the “chelation solution” contains vitamins, electrolytes, an anesthetic, and heparin?

    Heparin is a fast acting anti-coagulant used in hospitals when initiating a long term anti-coagulant regimen. At-risk cardiac patients are placed on an initial dose of heparin which is later replaced by a longer acting anti-coagulant like Coumadin. How do they distinguish the effect of EDTA from the anti-coagulation benefit of heparin?

    I get that they are adding back vitamins and electrolytes to offset the iron, calcium, and magnesium that will be the vast majority of what the EDTA chelates. However, when you are adding this many variables to a treatment, you’re not really isolating for EDTA. The found benefit was near statistical insignificance and you can’t really say that any effect was due to chelation.


  3. Rand
    November 5, 2012 at 4:39 PM

    Look on the bright side… the study may have provided evidence that the treatment is complete bunk…. but on the other hand, it did not apparently show any *negative* consequences to the treatment (aside from false hopes, financial losses, and the potential to mislead patients from seeking more effective treatments…). It did not, apparently, actually make things worse for them…

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