Antidepressant Studies Suppressed? A report in the New England Journal of Medicine says most studies that get published about antidepressants are positive, while negative studies remain unpublished. We speak with Dr. Steven Nissen, who proposes that all studies be placed in a public registry.
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Antidepressant Studies Suppressed?

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Antidepressant Studies Suppressed?

Antidepressant Studies Suppressed?

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  • <iframe src="" width="100%" height="290" frameborder="0" scrolling="no" title="NPR embedded audio player">
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This is DAY TO DAY from NPR News. I'm Alex Cohen.

It's hard to keep up with all the new medications and antidepressants on the market. And according to a new report, there's a lot of information we may not be getting about these drugs and how well they work. According to the New England Journal of Medicine, many negative studies, studies that found no benefits to these drugs, never make it into official medical journals. Guess what? The positive studies almost always do.

Joining us to talk about this is Dr. Steven Nissen. He's a cardiologist at the Cleveland Clinic. Welcome to the program.

Dr. STEVEN NISSEN (Cardiologist): Thank you.

COHEN: So tell us, what exactly did The New England Journal of Medicine study find?

Dr. NISSEN: Well, they were reporting on antidepressant clinical trials. And the information suggests that when you look at the totality of information, there was something like 74 trials available to these investigators. And they looked at the number of them that were published and number of them that were unpublished but reported to the FDA. Companies are required to report all studies to the FDA, but they had not been previously required to actually publish them.

Of the studies that were published, 94 percent of them were positive. If you look at, however, at the totality of information, including the unpublished studies, only 51 percent were positive. And so it's another very clear example where information that suggests that drugs are working and are free from side effects ends up in the medical literature. Information that suggests that perhaps they don't work or have adverse effects never get published.

COHEN: And could this be true that - the fact that these negative studies aren't surfacing in these journals, could this be true of other drugs as well?

Dr. NISSEN: This has been true overwhelmingly for virtually all classes of drugs, for as long as certainly I can remember. It differs somewhat in how bad the problem is, according to what kind of drug we're talking about. But it's always there to some extent.

COHEN: And why aren't these studies being published? Is that the publishers of these journals' choices? Is it pressure from the drug companies? What's going on?

Dr. NISSEN: Certainly, historically there may have been some reluctance on the part of journals to publish negative studies. They just don't seem as attractive.

COHEN: They're not as exciting.

Dr. NISSEN: Not as exciting. But that's changed a lot. And journals, I don't think, are the problem. The real problem in most people's view is that the vast majority of trials - the vast majority of them are run by the industries - that is, by the pharmaceutical or device industry. And it's not in their economic interests to publish studies which show adverse effects or lack of efficacy for their products.

This has been countered by a movement toward developing academic coordinating centers. These are large centers - we happen to have one here at the Cleveland Clinic - where academic physicians actually run the trial and where the contract for doing the trials specifies that the academic investigators have the independent right to publish the results. The bad news is that perhaps only about one percent of clinical trials are actually done by these independent clinical trial centers.

COHEN: And what about the people who volunteer for these trials? What does it mean to them if the data that they volunteered for doesn't even make it into these journals?

Dr. NISSEN: People are wonderful. They want to help their fellow patients to advance science, and that's why they volunteer. And they get poked and prodded and they give blood and they have X-rays done and they do all these things, and then we turn around and if we don't publish the results, what have we done for those people? All of their efforts led to no advancement of science, and that's just not right.

COHEN: So what's going to be done about this? I mean, it seems to me that if you've got now the drug companies have to when they run TV ads tell you about the side effects of their medication, shouldn't there be some kind of legal requirement to make sure the negative studies are published as well?

Dr. NISSEN: Well, there is, finally. There was a huge battle that took place in Washington in the Congress over the last two years. This was over the FDA reauthorization bill that was finally passed and signed by the president on September 27th last year. In this bill is a provision that says basically that companies have to release the results of clinical trials.

Now, there are some exceptions. For example, studies of drugs that never make it to the market are excluded in the law. But fundamentally it has now become the law of the land. There is money in the bill so that the National Institute of Health can actually create a system, a Web site where these trials will be registered and the results will then be presented.

COHEN: Dr. Steven Nissen of the Cleveland Clinic, thanks for joining us.

Dr. NISSEN: My pleasure.

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