Secondary prevention of coronary heart disease in elderly patients following myocardial infarction: are all HMG-CoA reductase inhibitors alike?

Abstract

Cardiovascular disease remains the leading cause of mortality in elderly patients. While coronary heart disease (CHD) morbidity and mortality have decreased over the last 25 years, the percentage reduction in elderly patients is nearly 50% lower than that for the general adult population. Therefore, aggressive primary and secondary prevention of CHD is imperative for our society, and hyperlipidaemia remains the major modifiable risk factor in the elderly population. However, there appears to be a reluctance among practitioners to treat hyperlipidaemia in elderly patients, a bias that is particularly important given the absolute benefits of treating such patients. While many of the major clinical trials involving HMG-CoA reductase inhibitors (statins) in patients with CHD focused on younger individuals, subsequent subgroup analyses of elderly patients have shown consistent reductions in all-cause mortality, major CHD events and numbers of revascularization procedures. Intensive statin therapy in the setting of acute myocardial infarction (MI) has also been shown to reduce the risk of death, MI, unstable angina, revascularization and stroke in elderly patients. Furthermore, three recent articles that have evaluated intensive lipid-lowering in the elderly population have extended the known benefits of such therapy to elderly patients with acute coronary syndrome and stable CHD.Elderly patients often take multiple medications and are at significant risk of drug-drug interactions. Several available statin medications are metabolized by cytochrome P450 (CYP) 3A4 and can therefore interact with commonly used medications such as amiodarone, macrolide antibacterials, calcium channel antagonists, fibric acid derivatives and ciclosporin. These interactions can result in an increased frequency of statin-related hepatotoxicity and myopathy.There are currently six commercially available statin medications on the US market, three of which, lovastatin, simvastatin and pravastatin, are available in generic formulations, and are thus less expensive. Of the commercially available statins, rosuvastatin, atorvastatin and simvastatin have the highest potency. While rosuvastatin currently lacks clinical event data, atorvastatin has the most clinical event data for CHD and even stroke prevention. Although pravastatin has lower potency than other described statins, it also has the lowest risk of drug-drug interactions involving CYP.