Studies have consistently shown that coronary heart disease (CHD) risk is correlated closely with low density lipoprotein (LDL) cholesterol levels. The lower the LDL cholesterol, the lower the cardiovascular (CV) risk; however, there is a question over how much LDL cholesterol lowering is low enough and what supporting evidence there is for this. This article reviews recent evidence in support of the notion that 'lower LDL cholesterol is better,ÔÇÖ drawing on revised guidelines from the National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III). Data are presented to show that, in clinical practice, the majority of patients are treated suboptimally with traditional single inhibition statin monotherapy. In contrast, ezetimibe/simvastatin, a dual inhibitor of both cholesterol absorption and production, represents a more effective approach to treatment, allowing more patients to meet or exceed their LDL cholesterol goals.
Epidemiology has repeatedly shown that elevated levels of cholesterol play a key role in the development of atherosclerotic disease. In particular, low density lipoprotein (LDL) cholesterol has been strongly associated with coronary heart disease (CHD) risk.1-5 Lowering LDL cholesterol reduces the incidence of atherosclerotic disease, irrespective of how the reduction is achieved. The efficacy of statins in this respect is well-known,6 but similar improvements in CHD events can also be seen if a LDL cholesterol reduction is provided by cholestyramine and even surgical bypass.7-9 The message is clear and has been proven - lowering LDL cholesterol improves cardiovascular (CV) outcomes, irrespective of the mode; however, there is a question over how much LDL cholesterol lowering is low enough and what supporting evidence there is for this.
Statins, LDL Cholesterol and CHD Risk Reduction
Studies of statin usage in both primary and secondary prevention settings have shown consistently that the risk of a CHD event is correlated closely with LDL cholesterol levels (see Figure 1).7-10 The results are impressive. The benefits of lowering LDL cholesterol levels extend to men and women with widely differing CV risk profiles and include reductions in CHD and total mortality as well as myocardial infarction (MI), revascularisation procedures, stroke and peripheral vascular disease (PVD).11
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