Interpreting Medical News in the Media

An Interview with Brooks Edwards, M.D.

Brooks Edwards, M.D., a Mayo Clinic cardiologist, has been at Mayo Clinic since 1989. Dr. Edwards is the medical director of the cardiac transplant team at Mayo Clinic, He is a professor of medicine at Mayo Clinic College of Medicine and served as medical editor in chief of MayoClinic.com, Mayo's consumer health information Web site. Here he talks about interpreting medical news in the media.

WHS: We seem to be inundated with medical news stories these days. Are there actually more medical breakthroughs than before or does it just seem like it?
Dr. Edwards: I don't know that there are more breakthroughs. More than anything, I think it's an attempt by the media to provide information to readers who are genuinely interested in health-0realted topics.

WHS: Medical studies in the news often appear conflicting, especially regarding lifestyle issues such as alcohol or caffeine consumption. How can a reader get some straight answers?
Dr. Edwards: Unfortunately, I don't have a one-size-fits-all answer. I think people need to talk to their health care providers and come up with an individualized approach that works for them. Doctors and patients have to take the best data available at the time and be willing to re-evaluate their position as new data come along.

WHS: The terms risk and benefit are commonly used. What do they mean?
Dr. Edwards: Anything that has the potential to do good also has, at least in some people, the potential to do harm. The balance between the potential harm and the potential good is the risk-benefit ratio. So if the treatment or procedure is helpful in a thousand people but has potential harmful effects in only one patient, that's one thing. If on the other hand, it may help 10 people but harm five, that's a different ratio.

WHS: Why do doctors often seem much more skeptical of new medical studies than other people are?
Dr. Edwards: A lot of experienced practitioners have been seen reported cures and miraculous treatments come and go. Something may look like a major breakthrough, and you later find out it wasn't as effective as initially promoted or it carries significant risks.

Oftentimes, clinical trials are done on only 50, 100, or 500 people. Then, when the drug gets rolled out into the general public, you suddenly have thousands or hundreds of thousands of people on a particular therapy. If a problem occurs only one in 1,000 times, it may not be seen in the clinical trials, but it may become a real concern in the general population.

Also, clinical trials tend to have a very homogenous study population. People who enroll in clinical trials generally have to meet certain characteristics. So when the drug or treatment is approved for the general public, it's then used on a much wider, more diverse group of people.

WHS: Do you think this is reflected in the problems that occurred with the arthritis drug Vioxx?
Dr. Edwards: Yes, I do. Remember that the frequency of problems with Vioxx or Celebrex is still very small. So, you only see it when you're studying tens of thousands of people. In the course of any one small clinical trial or in the course of one doctor's unique clinical practice, there will be some people who have a heart attack, simply because heart disease is one of the most common conditions in the United States. You may never associate a person's heart attack with the fact that he or she is on Vioxx. That's because many people who aren't on Vioxx are also going to have a heart attack. It's only when you get really large numbers of people being treated that these small effects are seen.

WHS: Should people take a page from their doctors and keep a healthy skepticism of their own?
Dr. Edwards: There are times to be skeptical, and there are times not to be skeptical. For example, statin drugs are extraordinarily effective in reducing the risk of heart attack and stroke in a lot of people. At the same time, some statin drugs have a higher risk of complications than do others. Some of my patients are skeptical of statins. So I tell them, let's figure out one that has the lowest risk for you.

On one hand, the skepticism is right. I wouldn't want some of my patients on a statin with a high risk of complications because the risk would exceed the benefit. On the other hand, if you refuse to take any statins despite having a cholesterol of 300, for example, then skepticism may be a problem.

Visiting with your doctor can help you know when to be skeptical and when not. As we try to empower our patients to be better partners in their own health care, I don't think we want to take all the responsibility off the doctor to provide some guidance in these challenging matters.

WHS: Can you provide some basic tips on what to look for in a medical report that's being highlighted in the news?
Dr. Edwards: First think to consider is whether these reports are about real people with real diseases or are they preliminary results obtained from studies conducted in laboratory animals? Although animal studies provide clues about the mechanism of a particular illness or treatment, results can't be definitively translated to humans until human trials are conducted.

Second, what kind of numbers are we talking about? Did this breakthrough occur in only a half dozen people, or has it been tried in a large group of say, a thousand people?

Third, how rigorously was the trial performed? Some trials have better control of factors that could potentially bias the results. For example, a large randomized, double-blind trial (when neither the researchers nor the study participants know who's receiving the treatment being studied) is generally designed to account for biasing factors, more so than a study based on a small number of case reports.

Finally, it's also fair to ask who's sponsoring the trial. Is there a potential conflict of interest between the trial's sponsors and the results? If a trial's sponsor has a vested interested in a positive outcome, that doesn't mean that important things can't be learned, but you would probably want to be more skeptical than if the trial was performed at the National Institutes of Health, for example.

You want to make a distinction between health sources with promotional intent versus those that primarily provide health information.

Medical research is in a constant state of flux, and definitive answers aren't always going to be available. Studies are limited in scope. A single study may be reported widely in the news, but in order to provide conclusive evidence, it must be supported by other studies and be borne out over time. When a treatment has been studied only in animals, it's too early to tell whether it has practical applications for humans.

Every treatment has a balance between potential risk and potential benefit. How much risk is acceptable generally depends on the severity of the disease and the importance of finding a treatment.

When reading about a new medical study, consider whether the source is reputable and trustworthy. Then ask your doctor for guidance in deciding if the study results are relevant for you.

Source:
Supplement to Mayo Clinic Women's HealthSource, May 2005