PURPOSE: The statin-prescribing patterns in a large managed care organization and the effectiveness of statin prescriptions in lowering low-density-lipoprotein (LDL) cholesterol levels in patients with coronary artery disease (CAD) or risk-equivalent patients were examined. METHODS: A retrospective review of the records in an integrated medical, pharmacy, and laboratory database was performed. The qualifying period for the study began January 1, 1999, and ended December 31, 2000; the reporting period extended from January 1, 2001, to December 31, 2001. Patients included in this study had a medical claim indicative of a diagnosis of CAD or risk equivalence during the qualifying 18-month period. The data were examined to determine percentages of patients who were tested for circulating LDL cholesterol levels, were prescribed statins, and achieved the LDL cholesterol goal recommended by the National Cholesterol Expert Panel. Physician prescribing patterns were also examined. RESULTS: During the 12-month analysis period of the study, 24% of patients were tested for circulating LDL cholesterol levels, and 39.8% received at least one statin. Of patients whose LDL cholesterol values were documented and who received statins, 44.5% achieved goal LDL cholesterol levels. Of patients who were tested and did not receive statins, 29.8% achieved the LDL cholesterol goal. Cardiologists prescribed statins to CAD patients at a higher rate than other specialists or primary care providers. CONCLUSION: Patients with a diagnosis of CAD or risk equivalence, who would benefit from treatment to reduce circulating LDL cholesterol levels, were significantly undertreated.