A Comparison of Clinical Outcome Studies among Cholesterol-Lowering Agents

OBJECTIVE: To review and compare clinical trials of cholesterol-lowering agents that evaluated clinical end points as the primary outcome measure; specifically, to determine whether all agents that decrease cholesterol impact clinical outcomes similarly. DATA SOURCES: Primary articles were identified through a MEDLINE search (1966-February 2001) and through secondary sources. STUDY SELECTION AND DATA EXTRACTION: All of the articles identified from the data sources were evaluated. Articles that included clinical end points as the primary outcome measure were included in this review. DATA SYNTHESIS: Clinical trials were assessed according to study population (primary vs. secondary prevention of coronary artery disease), baseline and follow-up lipid profiles, and clinical outcome data. Both cardiac and noncardiac morbidity and mortality were evaluated. The differences in study populations, study methods, and changes in lipid values were compared and contrasted between trials to evaluate their effect on outcomes. CONCLUSIONS: Niacin and bile acid sequestrants should be considered as add-on therapy when therapeutic goals cannot be attained with a hydroxymethyl glutaryl-coenzyme A reductase inhibitor (stain). Estrogen therapy cannot be recommended solely for cardioprotection. Fibrates are most effective in patients with high baseline triglycerides, low baseline high-density lipoprotein cholesterol, and low to average low-density lipoprotein cholesterol (LDL). Statins are considered first line for the treatment of elevated LDL in both the primary and secondary prevention of coronary heart disease. They are well tolerated, have the strongest data to support their use, and have been shown to decrease total mortality.