The ENHANCE study results were released recently leading to a media frenzy complete with hysteria, conspiracy theories and lots of general mis-information.

The study compared the effects of Zocor (simvastatin) and Vytorin (simvastatin plus Zytia) on the thickness of the wall of the carotid artery (a marker for atherosclerosis) in 720 Familial Hyperlipidemia patients. They all started with a pre-treatment LDL of 320 mg%. The Zocor arm lowered their LDL to 189 mg% while the Vytorin arm got down to an LDL of 134%. The hope was, that in the spirit of “lower LDL is better”, the group on Vytorin would do better, but the study showed NO DIFFERENCE between the two treatment arms after two years of therapy (NOT that the Vytorin arm did worse, as was reported by several sources). Both treatment arms were well tolerated and there were no safety concerns with either the Zocor or Vytorin.

It must be emphasized that Familial Hyperlipidemia is a rare (1 in 500 persons) genetic disorder that is not representative of the high cholesterol in the vast majority of Americans. The baseline LDL was extremely high and the on-treatment LDL’s were in the mid to high 100’s – a level too high to expect to see an appreciable effect on atherosclerosis. Almost all previous studies showing a positive effect on atherosclerosis got the LDL level down to well below 100 mg%. ENHANCE was not an “event trial” (looking a actual heart attacks, strokes or death) – the study looked at an anatomical surrogate marker trying to measure changes that literally were less than the width of a human hair.

Doctors’ offices were flooded with calls from concerned patients after the media blitz and the best advice for the public taking either Vytorin or Zetia is to stay on their medications. The overwhelming weight of medical evidence does in fact support the concept of “lower LDL is better” even if ENHANCE failed to demonstrate it.