Evidence-based medicine has a lot of promise to help ensure high-quality care, and in some cases, lower costs. For patients with stable coronary artery disease, there is a pattern of optimal medical therapy, involving drugs, diet, and exercise recommendations, that is less expensive, and probably less risky, than interventional procedures such as stenting. Randomized clinical trials have shown no benefit to this percutaneous coronary intervention in these patients. Research published in the Journal of the American Medical Association examined whether these trial results, widely publicized to physicians, resulted in a change in practice patterns. (JAMA Article)
The researchers used a national registry of cardiac disease patients to identify practice patterns in the period prior to the randomized trial result’s release and afterward. The study population was about 467,000 people. Before the randomized trial, the use of optimal medical therapy was about 43% at the time PCI was performed and about 63% after PCI. After the trial, which again showed no benefit to PCI over OMT, the rate of optimal medical therapy before using PCI was around 45% and after PCI around 66%. No significant change in practice pattern at all.
The authors refer to the challenge of translating comparative effectiveness research to real world practice. There might be a simpler explanation. First of all, why are so few of these patients receiving OMT, basically a set of drugs, when they have CAD? Perhaps it is because their physicians are very focused on interventional procedures, from which they get a great deal more money. The most likely explanation for the results of this research is that the physicians ignored the risk and additional expense to their patients and went for the treatment that maximized their own income.