Comment by mcguire | Hacker News Reader

Comment by mcguire | Hacker News Reader

"For the study [...] recruited 200 patients with a profoundly blocked coronary artery and chest pain severe enough to limit physical activity, common reasons for inserting a stent.

"All were treated for six weeks with drugs to reduce the risk of a heart attack, like aspirin, a statin and a blood pressure drug, as well as medications that relieve chest pain by slowing the heart or opening blood vessels.

"Then the subjects had a procedure: a real or fake insertion of a stent. This is one of the few studies in cardiology in which a sham procedure was given to controls who were then compared to patients receiving the actual treatment.

"In both groups, doctors threaded a catheter through the groin or wrist of the patient and, with X-ray guidance, up to the blocked artery. Once the catheter reached the blockage, the doctor inserted a stent or, if the patient was getting the sham procedure, simply pulled the catheter out."

I would really like to know how they got that study past the assorted ethics committees.

> One day when I was a junior medical student, a very important Boston surgeon visited the school and delivered a great treatise on a large number of patients who had undergone successful operations for vascular reconstruction. At the end of the lecture, a young student at the back of the room timidly asked, "Do you have any controls?" Well, the great surgeon drew himself up to his full height, hit the desk, and said, "Do you mean did I not operate on half the patients?" The hall grew very quiet then. The voice at the back of the room very hesitantly replied, "Yes, that's what I had in mind." Then the visitor's fist really came down as he thundered, "Of course not. That would have doomed half of them to their death." God, it was quiet then, and one could scarcely hear the small voice ask, "Which half?"

–Dr. E. E. Peacock, Jr., University of Arizona College of Medicine; Medical World News (September 1, 1972), p. 45, as quoted in Tufte's Data Analysis for Politics and Policy

"Stenting is so accepted that American cardiologists said they were amazed ethics boards agreed to a study with a sham control group.

But in the United Kingdom, said Dr. Davies, getting approval for the study was not so difficult. Neither was it difficult to find patients.

“There are many people who are open to research, and if you tell them you are exploring a question, people agree,” he said. Nonetheless, it took him three and a half years to find the subjects for his study.

Ethics boards at many American hospitals probably would resist, since giving such patients fake procedures “flies in the face of guidelines,” Dr. Boden said."

In a practical sense, I wonder how they'd successfully do it in the US.

Stents cost on the order of $11k-$44k per the article. Wouldn't you just know from looking at your bill afterward whether you got the stent or not?

A simple way around that would be to pay for them so that no patient was billed for one.

Is there not a problem that in the US it would encourage people who otherwise couldn't afford the operation to opt for the "riskier" trial, even if they'd really prefer not to. Whereas in the UK, they would have received the operation free in or out of the trial, therefore the patients financial situation wouldn't factor in to their decision to join. Which feels significantly more ethical to me.

In theory you either have insurance that should cover this (more than 90% of Americans are covered), or else you'd be too poor to really even be able to afford such an operation or medical care. The system sucks, but I don't think the way the system is set up would cause a significant number of people to use free research for medical alternatives.

Even if you have insurance you get a statement from your insurance provider detailing how much everything cost and how much of it insurance paid for.

People in a clinical trial typically don't pay for the treatment (or placebo).

Hints in the full text:

"...it might be unethical to expose patients to an invasive placebo procedure. However, no evidence of harm to placebo groups was found in a systematic review of placebo-controlled surgical trials... After the follow-up assessments, study participation was complete, and patients and physicians were then unblinded to the treatment group allocation. Patients who had the placebo procedure had the opportunity to choose to undergo PCI after consultation with their physician."

But yes, it must have taken a lot of persuasion to get through ethical approval.

Disclaimer: Haven't had a chance to read the original paper yet. IIRC, there was already pretty good evidence that angioplasty (without stenting) does not lower risk of death from heart disease unless there is actually an acute myocardial infarction (heart attack) in progress. In other words, if done in people having chest pain due to intermittently insufficient blood flow (angina), but not actually having a heart attack, there was no difference in death / disability, but there was less pain afterwards. Both angioplasty and stenting definitely help (reduced risk of death / disability) in people having acute heart attacks.

There are also complications associated with stents. I certainly don't think it was unethical, but I agree with your question for this reason - many studies that may be ethical, but may lead to reduced sales of very expensive items somehow are deemed 'unethical'. I assume the way they did it was that everyone got a diagnostic angiogram, but only the experimental group got the stent. That way there was still benefit to all the patients (assuming diagnostic angiography is useful...), whether or not they got the stent.

I had the same thought! However, the article mentions at some point that the drugs were the "optimal treatment"... implying that the exact value/necessity of stenting is... a little... unclear? Maybe I misunderstand, but perhaps a stent is like the cherry on top of the aspirin/statin/blood pressure regimen.

I guess the patients knew they were taking part in an experiment, and got paid for it.

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