Combination Therapy With Ezetimibe/Simvastatin Versus Statin Monotherapy for Low-Density Lipoprotein Cholesterol Reduction and Goal Attainment in a Real-World Clinical Setting

Abstract

Background Randomized studies have demonstrated improved attainment of target low-density lipoprotein cholesterol (LDL-C) values when ezetimibe is combined with statins for the treatment of hypercholesterolemia. However, the efficacy of an intervention in randomized controlled clinical studies may not correlate with its efficacy in a real-world (community practice) setting. Data to support the LDL-C lowering efficacy of ezetimibe/simvastatin (EZE/SMV) outside of controlled clinical studies are currently lacking. Objective Using patient data from a large, national, administrative claims database, this retrospective observational study evaluated the efficacy of EZE/SMV in lowering LDL-C values and achieving LDL-C target values in newly initiating users and compared the results with those from several statin monotherapies. Methods Patients with hypercholesterolemia who had filled their first prescription for EZE/SMV or statin monotherapy between July 1, 2004, and December 31, 2007, and were ≥18 years old were evaluated. Pertinent data taken from the database included lipid-lowering drug name, date of first prescription, dose, serum lipid levels, and sample dates. Data on cardiovascular history, diabetes, and other concurrent diseases and therapies were also available. Following propensity score matching, multivariate regression models were constructed to estimate the impact of the choice of therapy on key treatment outcomes including the reduction of LDL-C (absolute and percent) as well as the percent of patients achieving goal LDL-C levels as defined by the updated American Heart Association/American College of Cardiology (AHA/ACC) Guidelines for 2006. Results In the total population, both the percent decrease and the absolute reduction in LDL-C values were significantly greater with the use of EZE/SMV than with the 3 statin monotherapies ( P < 0.005 for all comparisons). A significantly greater percentage of patients achieved AHA/ACC LDL-C goals in the first 3 months of EZE/SMV treatment compared with those using each statin monotherapy ( P < 0.05 for all comparisons). Among matched patients with diagnosed diabetes, the percent reduction in LDL-C was also higher with the use of EZE/SMV than with each statin monotherapy ( P < 0.005 for all comparisons). Conclusion In a real-world setting, EZE/SMV appeared to be more effective than simvastatin, atorvastatin, or rosuvastatin monotherapy for attaining therapeutic goals set forth by national and professional societies in patients being initiated on statin-based lipid-lowering therapy.