What's a doctor to do when findings change course? Guiding patients through evolving medical evidence

Washington -- In recent weeks, the realm of health evidence has experienced a seismic shift, and physicians are eyeing new findings with caution and recommending that patients do the same.

Fresh studies seem to contradict standard medical advice such as the ideas that low-fat diets are heart-healthy and calcium and vitamin D provide good protection against fractures. Thus, helping patients sort through the maze of conflicting research results -- always a challenge --is even more difficult.

Keeping up with such developments when medical news hits the morning papers and television is now an important part of a physician's job. Many of the news articles even urge people to "ask their doctors" about anything and everything.

But at the same time, physicians are becoming savvy to shifting data, and most can readily resolve confusion. All too often, findings diverge from what's seen as common wisdom.

Vitamin E is a good example, said Donna Sweet, MD, an internist in Wichita, Kan. "First it was in, and then it was out, and then in again, and now it's out."

Hormone replacement is another classic illustration. Estrogen and progestin had been thought to protect women's hearts until the Women's Health Initiative turned that notion on its head in 2002. Now a new look at the data suggests women ages 50 to 59 who take estrogen alone might lower their risk for coronary heart disease.

This latest interpretation could seem something of a flip-flop to women who turned away from HT when initial findings were released.

Physicians are seeking ways to assimilate the new information into the larger body of evidence.

"Each of these studies and the medical literature is an ongoing, ever-changing dialogue amongst the health profession and the scientists," said Barnett Kramer, MD, MPH, associate director for disease prevention at the National Institutes of Health. "It's very rare that something will end the entire dialogue or the entire story."

"The only thing you can do as a physician is to represent that evidence is never static but always changing and that we operate on the best evidence we know," said Eric Wall, MD, MPH, a family physician in Portland, Ore.

"I tell women not to change the course of whatever therapy their clinicians have them on," Dr. Sweet said. "Whether it's vitamin E or calcium plus vitamin D, don't suddenly stop because of what you see on the evening news."

Physicians also must interpret data from large trials for individual patients, Dr. Sweet said. "It's a risk and benefit based on personal history."

"Medicine is an inexact science," noted AMA Trustee Ronald Davis, MD. "Patients need to understand that given their physiology, medical treatments don't always behave as precisely as the laws of physics."

Dr. Davis advises patients to consult authorities for help in interpreting conflicting studies. Primary care physicians, the AMA and medical societies, as well as federal agencies such as the Centers for Disease Control and Prevention, are resources.

Slow and steady also might be good when it comes to weighing study results. Many physicians turn to clinical guidelines for assistance.

Dr. Wall said doctors fall into two camps: the "early adopters" of the latest conclusions and their opposites, the "slow adopters" -- those who resist change. The rapid swings often favor the physician who is a slow adopter, he said. "If you wait long enough, the evidence changes."

Steve Hillson, MD, a general internist and associate professor of medicine at the University of Minnesota, has been around long enough to be wary, especially when new information dramatically differs from a well-regarded body of evidence.

"I've seen way too much to say, 'We know this for sure,' only to have to go back later and say, 'We didn't mean it after all,' " Dr. Hillson said. And managing an ever-changing collection of knowledge isn't as aggravating if it's not presented as the final word, he noted.

But he acknowledged that frustrations had arisen. "I was all over HT in the early 80s and 90s like everybody else, and I backpedaled slowly but clearly over the last few years, and now again you are a little unsure."

The grounds for the new go-round of discussions are, like the 2002 HT study, the latest results from the WHI.

Findings from the initiative, published in the Feb. 8 Journal of the American Medical Association, revealed that a low-fat diet had no significant effect on the incidence of heart disease, stroke, breast cancer or colorectal cancer.

That study set off an explosion of news stories and editorials, including one from The New York Times that said, "The more we learn about nutrition, the less we seem to know."

Then, along came another study, this one in the Feb. 16 New England Journal of Medicine, indicating that calcium and vitamin D supplements provided only modest protection from fractures and increased the risk of kidney stones.

Some physicians would like the media to take a collective deep breath before splashing the latest research reports across the front page. "I think we're seeing almost a media frenzy over health news," Dr. Sweet said. "You didn't see these kinds of studies hit the evening news and the morning papers even a few years ago."

"Sometimes what gets picked up may be more negative than what is out there," she said.

Some conflicts between the media and medicine could be resolved via collaboration, said David Katz, MD, MPH, associate professor of public health at Yale University School of Medicine. But it's not likely to happen, given the clash between those in medicine who want to play down certain findings and newspaper editors and television producers who want to boost their entertainment value, said Dr. Katz, who, as a contributor to ABC News, sees both sides.

Until a better solution reveals itself, doctors need to tell patients, "It's my job to pay attention to the new information, consider it and offer advice to you accordingly," Dr. Katz said. The message: "If I'm not changing my mind because of this new study, it's because I don't think I should, not because I'm unaware of it."

It all comes down to the relationship, he said. "A well-informed doctor who has the trust of patients can set it all right."