Which patients with coronary disease have been proven to benefit from pharmacological intervention? What lipid levels should I aim for?

Three major statin trials (4S1, CARE2 and LIPID3) involving approximately 18,000 patients have provided unequivocal evidence of benefit of cholesterol-lowering in patients with established coronary heart disease (CHD, angina, unstable angina, post-myocardial infarction). The question might be better phrased, which CHD patient should not receive statins, as the overwhelming majority are likely to show substantial benefit. Debate remains concerning the optimal treatment goal for LDL and the level at which treatment should be initiated. The lesson from interpopulation epidemiology is that there is no threshold effect for cholesterol and CHD and the relationship is maintained at low levels. Furthermore, in LIPID the cholesterol inclusion criteria went down to 4mmol/l. The recent joint British guidelines suggest that treatment should be initiated at a total cholesterol >5mmol/l (LDL >3mmol/l) and the goal should be cholesterol <5 and LDL <3mmol/l. In the American Heart Association guidelines the goal of therapy is an LDL cholesterol <2.6mmol/l. How low to lower LDL remains an open question. Preliminary evidence from the Post Coronary Artery Bypass Trial4 suggests that lower is better but this was an angiographic rather than an event study. Ongoing studies such as TNT and SEARCH will provide more definitive information on this question. In the meantime it is the clinical practice of the author to lower LDL cholesterol if possible to <2.5mmol/l.