In case you missed it, health reporters who cover medical studies had a shining moment recently. It centered around the heavily stage-managed publication of the Trial to Assess Chelation Therapy, or TACT.
TACT was a 10-year double-blind, randomized controlled study of 1,708 patients that was carried out at 134 sites in the U.S. and Canada. It cost the government and, by extension, taxpayers, $31 million. About 60 percent of the sites were traditional chelation centers – some of which had shaky legal histories, the rest were traditional cardiology practices and academic medical centers, including Johns Hopkins Bayview Medical Center and the Mayo Clinic.
When the results of the trial were first released at the annual meeting of the American Heart Association last fall, they showed that weekly, three-hour chelation infusions may offer small benefits to some patients who have suffered a heart attack. The therapy didn’t seem to prevent deaths, but there were fewer additional procedures like stents and bypass surgeries in group that got chelation compared to the group that got a placebo infusion. Most of that difference was seen in patients with diabetes, leading at least one perplexed doctor to ask whether the placebo infusion, which contained some sugar, might actually have harmed the diabetics – thus accounting for the apparent benefit of the trial.
The results touched off a firestorm of criticism from doctors. Coverage of the trial topped the Google health news page for days, with one side calling TACT a fatally flawed study, while the other chastised naysayers for cherry picking the evidence they wanted to believe.
Last week, the Journal of the American Medical Association published the peer-reviewed version of TACT. At a time when the journal has been working to shorten papers it publishes, JAMA dedicated fourteen full pages to the trial in the journal proper, including the study and two editorials. The first editorial was a sharply critical assessment by watchdog Steven Nissen, M.D., chief of cardiovascular medicine at the Cleveland Clinic. The second had JAMA’s top editors acting as apologists for their decision to publish the study. In addition to all that, JAMA took the very unusual step of releasing an additional 16 pages of its editorial review of the study with responses from the authors, a move that seemed designed to head off any critics who might have thought they’d gone soft on the study. All of the material came to the same conclusion: Chelation therapy is not ready for routine medical use.
Furor over the results doesn’t seem to have diminished, even with their second public airing. Larry Huston, author of the excellent Forbes blog CardioBrief has kindly compiled a handy and entertaining cheat sheet for those who are struggling to keep up with the back-and-forth.
This is all part of a healthy debate that medicine needs to have with itself. It makes me wish all studies of new or newly tested treatments were as carefully scrutinized.
Health reporters, for their parts, rose to the occasion of covering this complicated study. Gary Schwitzer would have run out of gold stars.
Some of the best examples came from Genevra Pittman at Reuters, who helpfully told us that chelation is expensive, costing between $2,000 and $5,000 for a package of treatments that are not typically covered by insurance, and Liz Szabo at USA Today, who reminded us that 30 people have died from off-label uses of chelation since the 1970s, including a 5-year-old boy. In easy-to-understand language, Szabo also explained that the trial barely squeaked past tests of statistical significance and had a high dropout rate. How high? She told us: Only 65 percent of patients finished all of their scheduled chelation treatments.
I was curious about the backstory of the trial, so I interviewed lead study author, Gervasio A. Lamas, M.D., chairman of medicine at Mount Sinai Medical Center in Miami Beach, Fla., and professor of clinical medicine at Columbia University Division of Cardiology. In my next Covering Health post, he talks about the process of getting the trial published and speaks to some of the main criticisms of the study.
