Medicine copes with changes in direction
By Stephen Smith
When researchers last week dropped bombshells debunking long-held beliefs about hormones and knee surgery, it was stunning – but hardly surprising.
The history of medicine is pocked with reversals, yesterday’s panacea branded as today’s poison.
Witness this swatch of advice, resounding with the august authority that Americans had come to expect from the white-jacketed high priests of medicine.
”The notion that a baby should not have direct sunlight is a major mistake,” Dr. Herman Bundesen, president of the Chicago Board of Health, wrote in 1938 on the pages of the Ladies’ Home Journal. ”When the baby is a month old, put him directly in the sunlight. The best time of the day is between 10 and 2 o’clock.”
Doctors changed their minds about that – just as they did last week when two medical studies challenged the value of hormone replacement therapy for women and knee surgery for arthritis-hobbled patients. Hormones, researchers found, actually increase a woman’s risk of some of the very ills they were intended to conquer, including heart disease. And, scientists reported, patients who underwent arthroscopic knee operations fared no better than those who got a sham procedure.
Patients who had undergone these treatments and critics of big medicine expressed annoyance and outrage. Yet medical historians and leading physicians view the twin reversals not as troubling setbacks for American medicine but as proof that the system is doing its job. Science is constantly reaching new conclusions about once-widely accepted treatments, a tradition that validates the need for rigorous research and the willingness to abandon medical orthodoxy.
Last week’s revelations also underscore profound shifts in how scientists evaluate what works and what doesn’t. Once, it was enough for individual physicians to observe how patients fared after swallowing a pill or enduring an operation. And, sometimes, as with the 1938 recommendation regarding the benefits of sun, blind intuition was embraced in the absence of unblinking scientific evidence.
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Today, the standards are far more exacting. Researchers subject drugs to elaborately designed trials, with scientists linked into networks involving dozens of universities and hospitals.
It turned out that hormones and arthroscopic knee surgery – treatments in broad use for decades – found themselves squeezed in the vise of past favorable anecdotal experience and present large-scale studies reporting major problems.
Left in the wake of these scientific course corrections: further damage to the once-easy confidence vested in doctors. For years, patients have lamented the confusion stirred by dueling medical studies, but both hormone replacement therapy and arthroscopic knee surgery stood as essential weapons in the medical arsenal. If researchers reverse course on them, ordinary patients wondered, what’s next?
”I understand the concern that this may undermine the sense of the infallibility of physicians,” said Dr. John G. Clarkson, dean of the University of Miami medical school. ”You know what? There’s nothing wrong with that because none of us are infallible, and clinical research is not infallible. What’s important is how we move forward and do a better job of taking care of patients by constantly questioning our suppositions and subjecting them to the scientific method.”
Such reconsiderations have been prominent features on the health care landscape for years. There’s thalidomide, for instance, a drug to reduce pregnant women’s morning sickness that was banned from the marketplace in the 1960s after being implicated as the cause of hideous birth defects. Now, it’s available again, used to treat leprosy. And, of course, a few generations back, lobotomies – the removal of a section of the brain – were acceptable treatment for the insane.
More recently, heart doctors found themselves altering their recommendations regarding diet. Once, stick margarine was in. Now, it’s out, since any benefits are trumped by concerns over transfatty acids, which cause cholesterol to spike.
”There’s a natural rhythm to a lot of discoveries in medicine,” said Dr. Mark Hlatky, a Stanford University cardiologist and health policy researcher. ”In the long run, there’s going to be ups and downs with clinical research. This is what gives you advances: You have an idea, you float the idea, and some of them don’t pan out.”
But rarely, if ever, has there been a week like the one just past.
First, researchers at the National Institutes of Health revealed that hormone replacement therapy taken by 6 million menopausal women does more harm than good. Touted for their supposed ability to prevent heart disease and cancer, hormones became commonplace in the medicine cabinets of millions of women – sometimes for life. But while the pills remain valuable in alleviating the consequences of menopause, the NIH scientists reported that long-term use can actually put women at peril, although the risk to individual women is slight.
Then, Texas scientists disclosed results showing that surgery performed on at least 225,000 Americans annually with arthritic knees was actually no better than a sham procedure performed in their study. It wasn’t so much that doctors were wrong when they perceived that patients improved. Rather, the Texas study calls into question whether that’s due to the procedure or, instead, can be attributed to the placebo effect – when a patient’s improvement is caused not by the medical treatment but by the belief that a pill or operation has helped.
”It can be confusing to the average person and even to the medical professional,” said Dr. Stephen Hulley, chairman of epidemiology and biostatistics at the University of California, San Francisco medical school. ”If you have different studies pointing in different directions and different experts drawing different conclusions, you obviously have a situation where it’s more difficult for the average person to make a good decision.”
How did this happen? How did hormone pills once hailed as a panacea for women with hot flashes and the other aspects of menopause go from medical savior to medical villain?
The answer, in large measure, resides in one of the pivotal shifts in 20th century medical history.
Physicians have always demanded evidence before prescribing a drug or a surgical procedure. It is the nature of that evidence that evolved so dramatically during the past quarter century.
Anecdotal experience once was the widely embraced standard. Give a patient a pill and if it works, then give the same pill to another patient with the same ailment.
”It’s sort of like when you’re a parent and you’re taking care of your children,” said Dr. Judy Ockene, a University of Massachusetts Medical School researcher and a principal investigator of the Women’s Health Initiative, which examined the hormone treatment. ”What you do with your children is based on whatever the evidence is telling you and what your own experience tells you is best.”
In fact, the experience with hormones is an object lesson in how things were – and how things have changed.
The pills, in use for six decades, were subjected to repeated medical trials reported in leading medical journals. But those studies were not the rigorous kind that are part of the medical canon today. Instead, conclusions were drawn simply by observing the effects of hormones on women who took the pills – there was no comparison group against which assumptions could be tested.
When he was a medical student more than 20 years ago, Stanford’s Hlatky recalls, there were few ”randomized” clinical trials. Those are the reviews of drugs that, with extreme precision, divide study participants into one group that gets the medicine under study, another that downs a dummy pill, and, sometimes, a third group that receives an entirely different treatment. Such studies typically proceed in a ”blind” fashion, meaning that neither participant nor researcher knows who got what pill until the research is complete.
Now that double blind approach is the gold standard. In fact, the NIH has established sites across the country designed to help researchers become better at their jobs. And those studies gain even more firepower by linking scientists into networks stretching from one coast to the other, a process designed to assure that the discovery at a lone university is no mere statistical anomaly.
The hormone study revealed last week followed that model, the first time the drug had been subjected to such unflinching scrutiny.
”We really now have a new capacity to critically assess therapies that we did not have before,” said Allan Brandt, a professor of the history of medicine at Harvard. ”Rather than seeing what happened with hormone replacement therapy and knee surgery as science having gone off in the wrong direction and now it needs to be corrected, it’s part of a constant process of evaluating therapeutic techniques based on new and innovative processes.”
It is a process likely to ensnare even more drugs and surgical procedures in the future. In fact, the experience with hormone replacement therapy and knee surgery could inspire evaluations anew of other long-embraced techniques and beliefs.
”There are lots of things out there that we do because that’s the way we’ve always done them,” Miami’s Clarkson said. ”And until we subject them to the scientific method, we will continue to do them.”
Instead of being cowed by the whipsaw of discovery from last week, researchers and historians said, patients should view the developments as an opportunity to seize control. Ask questions, they said. And demand scientific proof that what your doctor wants you to take really works.
”I think the patients should be happy,” Hlatky said. ”It’s scientific proof instead of just relying on expert opinion. If we just went with expert opinion, everybody would still think the world is flat.”