Precision Medicine Versus Evidence-Based Medicine

A 1986 Cleveland Clinic observational study showed that coronary artery bypass grafting with the left internal thoracic artery anastomosed to the left anterior descending artery provided better 10-year survival and graft patency than saphenous vein bypass grafts. Subsequently, it was demonstrated that use of both left and right internal thoracic arteries further improved survival. However, when Taggart and colleagues conducted a 28-site phase III randomized trial of using a single internal thoracic artery graft versus both internal thoracic arteries (ART [Arterial Revascularization Trial]), no survival difference was evident even at 10 years! The surprised investigators then searched for and found a subset of patients who appeared to benefit: those receiving 2 or more arterial grafts, including the radial artery. Although one can challenge a post hoc analysis of a negative trial, is it not worthwhile for any treatment to ask the questions, Who benefits? Who doesn’t? Who is harmed? At some level, we believe in “the right treatment for the right patient at the right time.” The right treatment involves discovering an individual patient treatment effect, the essence of precision medicine, not an average treatment effect as from a randomized trial, the gold standard for evidence-based medicine.

The full article can be downloaded below.