Is lowering LDL worth while?

Unless you are secluded on a remote desert island without any means of communication, you have surely heard that LDL is the "bad" cholesterol, that facilitates and leads to cardiovascular disease in excessive concentrations. Drug marketing companies make billions of dollars a year on drugs that lower LDL. This begs the question whether lowering LDL (possibly below certain limits) is indeed effective in mitigating the risk for heart disease. We note at the outset that statins do play a role in lowering the risk of heart disease, even though their role is also open to criticism. Statins also lower LDL, and so people assume that the benefit of statins is due to their lowering of LDL. However it is becoming evident that simply lowering LDL will not reduce the risk of heart disease.

The recently terminated ARBITER-6 HALTS (Arterial Biology for the Investigation of the Treatment Effects of Reducing Cholesterol 6– HDL and LDL Treatment Strategies in Atherosclerosis, reference 1) examined the effects of taking one of two supplementary drugs (ezetimibe or niacin) taken together with Zocor™ (simvastatin). Ezetimibe works by blocking cholesterol absorption from the digestive system into the blood stream. It results in significant lowering of LDL, beyong the lowering experience with simvastatin alone. However, measurement of the CIMT - carotid intima-media thickness which is a measure of the degree of atherosclerosis (hardening of the arteries, leading to their blockage) clearly indicated that it continued to thicken. For comparison, the patients on niacin showed that their artery thickness decreased slightly, even though their LDL levels were higher (73 mg/dl vs. 67 for ezetimibe-taking patients).

The inescapable conclusion is that low LDL in itself offers no protection agains atherosclerosis. Obviously, simvastatin alone did not provide significant protection either, since the disease continued to progress while taking it. The simvastatin + niacin combination appears to be the most protective.