Evidence points to the cure

The white lab coats doctors wear - particularly those emblazoned with academic credentials and professional accreditations - imply docs are knee-deep in the latest medical science.

Chances are, much of the medicine they're practicing is not. According to the Institute of Medicine (part of the National Academies), more than half of the medical treatments delivered today are done so without clear scientific evidence of their effectiveness.

The profession's propensity to trust intuition over science was on full display last week over a review panel's recommendations about screening for breast and cervical cancers. Political denunciations of the advice were to be expected. It was the cold reception from some in the medical community that was disheartening.

"Mammography saves lives!" was the most common refrain from doctors who criticized the advice that most women push back the age of routine mammograms from 40 to 50. What didn't get much traction, however, was a discussion of whether all this screening is producing all the benefits we've been promised.

Probably not. That's what the U.S. Preventive Services Task Force (breast cancer) and American College of Obstetricians and Gynecologists (cervical cancer) recommendations were telling us, a conclusion that's hardly breaking news.

One recent study found the emphasis on early screening produced a 40 percent increase in breast cancer diagnoses and a near doubling of early-stage cancer detection. However, there was only a 10 percent drop in breast cancers that spread to the lymph nodes or elsewhere. The findings were similar with prostate cancer.

Such large increases in early cancer detection should have paid off with a parallel decline in late-stage cancers. But they didn't. Some researchers contend that instead of concentrating on early detection, we should graduate to determining which tumors need treatment and which ones don't.

"The issue here is, as we look at cancer medicine over the last 35 or 40 years, we have always worked to treat cancer or to find cancer early," Dr. Otis Brawley, chief medical officer of the American Cancer Society, told The New York Times. "And we never sat back and actually thought, 'Are we treating the cancers that need to be treated?'"

Shannon Brownlee of the New America Foundation believes our failure to step back and reassess fundamental treatment premises is expensive and harmful to the public. Brownlee made a compelling case in her 2007 book, "Overtreated: Why Too Much Medicine is Making Us Sicker and Poorer." She argues the treatments doctors prescribe are based more on dogma than science. Her latest argument appears in the November issue of the Atlantic. She and co-author Jeanne Lenzer examine the effectiveness and cost of the common seasonal flu vaccine.

The two challenge the widely accepted and quoted claim that a flu shot can reduce the chance of mortality in seniors by 50 percent during the winter months. "That's not a vaccine, that's a miracle," Dr. Tom Jefferson head of the Vaccines Field at the Cochrane Collaboration in Rome, told Brownlee and Lenzer.

Dr. Lisa Jackson of the Group Health Research Center in Seattle also doubts the veracity of the 50 percent mortality reduction claim. She examined the medical records of more than 72,000 people over the age of 65. Her study found the mortality risk of the unvaccinated was indeed 60 percent higher. But that was true outside of the flu season as well, leading her to conclude the higher survival rate among vaccinated seniors is probably due to better overall health, not a flu shot.

Yet Jefferson and Jackson are sometimes described as medical pariahs.

What a shame. If health care reform is ever to become meaningful and costs manageable, emotional dismissals of evidence-based treatment research must end. Science, even when results are counterintuitive, must be allowed to discern between smart practices that yield tangible medical results and those that simply make the doctor feel good.

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