'Evidence Based' Medicine Misleads

Gina Kolata, writing in The New York Times in September, gushed about a blood pressure trial that was stopped a year early because the patients who were targeted to a lower pressure had lower heart attack and mortality rates.

I searched for the study, but it had not been published. Frankly, this is poor journalism. At least wait for the peer review process (such as it is) to run its course before trumpeting what are likely to be misleading results.

I say misleading because these results are unlikely to represent clinical reality. This is all the more true with a study stopped prematurely, since side effects often emerge over time and treatment is all too often life-long.

The brilliant scientist John Ioannidis wrote 10 years ago in a frequently cited paper, “For most study designs . . . it is more likely for a research claim to be false. Claimed research findings may be simply accurate measures of prevailing bias. The greater the financial and other interests and prejudices in a scientific field, the less likely the research findings are to be true."

The vast majority of blood pressure and cholesterol lowering trials are industry sponsored, and authored by physicians who are also industry sponsored.

The typical study takes a very small absolute risk reduction from a particular treatment, and then amplifies this by enrolling thousands of subjects, into a statistically significant relative risk reduction.

For example, drug X lowers five-year incidence of heart attack from 4 percent to 3 percent for an absolute risk reduction of 1 percent.

But this is a 25 percent relative risk reduction, and with enough subjects can be statistically significant.

This latter number is used almost exclusively in discussing the results. Who would not prescribe, or take, a drug that has been shown to reduce the risk of myocardial infarction by 25 percent?

The absolute risk reduction of 1 percent is trivial, and almost certainly clinically irrelevant, and will lead to massive over-treatment of the target population.

Medicine is increasingly under the control of advocates of so-called “evidence-based medicine.” In their devastating book, “Tarnished Gold: The Sickness of EBM,” Steve Hickey and Hilary Roberts write: “Evidence-based medicine, or EBM . . . is the conscientious, explicit, and judicious use of current best evidence in making decisions about the care of individual patients."

Supporters declared it as a new paradigm and a major scientific advance. They claimed the ideal way of making decisions about patients involved selective use of the best evidence from large-scale studies. "Since 2001, EBM has been on its way to replacing traditional medicine, which depended on understanding physiology and disease processes . . . basic science and clinical experience . . . were relegated to the lower divisions of medical evidence."

However, they continue, “in the context of scientific medicine, there is no such thing as best evidence, there is only information.  . . .  all information is potentially useful and, until you know the answer, it is prudent not to pre-select which evidence you think will be ‘best.'”

Here is the major problem with EBM: “EBM is based on a statistical blunder: the assumption that a population value can be applied to one specific individual. This is known as the ecological fallacy . . . it is fundamentally incorrect to apply the results of large-scale trials to individual patients. Despite this, the EBM myth is that individual patients should be treated according to a gold standard of population statistics. A doctor needs to treat every patient as a person with a unique problem . . . A doctor practicing purely according to statistical expectations will inevitably harm patients."

And herein lies the problem with the current direction of American medicine.

We are increasingly being constrained to practice based on evidence based medicine, without regard to the individual patient’s needs.

Doctors will be graded, and paid, based on achieving numerical targets for blood pressure, LDL cholesterol, blood glucose, and the like.

This will lead to even more massive over-prescribing, and will harm tens of thousands, if not millions, of individual patients.

Since 1990, Dr. Amerling has been on staff at the Beth Israel Medical Center (now Mount Sinai Beth Israel) in New York. He served as director of Outpatient Dialysis from 1995-2012. Amerling is board certified by the American Board of Internal Medicine for Internal Medicine and Nephrology. He also is president of the Association of American Physicians and Surgeons. He has been published in many journals. For more of his reports, Go Here Now.