Impact of Ezetimibe on the Rate of Cardiovascular-Related Hospitalizations and Associated Costs Among Patients With a Recent Acute Coronary Syndrome: Results From the IMPROVE-IT Trial (Improved Reduction of Outcomes: Vytorin Efficacy International Trial)

Abstract

Background: Ezetimibe, when added to simvastatin therapy, reduces cardiovascular events after recent acute coronary syndrome. However, the impact of ezetimibe on cardiovascular-related hospitalizations and associated costs is unknown.

Methods and results: We used patient-level data from the IMPROVE-IT (Improved Reduction of Outcomes: Vytorin Efficacy International Trial) to examine the impact of simvastatin-ezetimibe versus simvastatin-placebo on cardiovascular-related hospitalizations and related costs (excluding drug costs) over 7 years follow-up. Medicare Severity-Diagnosis Related Groups were assigned to all cardiovascular hospitalizations. Hospital costs were estimated using Medicare reimbursement rates for 2013. Associated physician costs were estimated as a percentage of hospital costs. The impact of treatment assignment on hospitalization rates and costs was estimated using Poisson and linear regression, respectively. There was a significantly lower cardiovascular hospitalization rate with ezetimibe compared with placebo (risk ratio, 0.95; 95% confidence interval, 0.90-0.99; P=0.031), mainly attributable to fewer hospitalizations for percutaneous coronary intervention, angina, and stroke. Consequently, cardiovascular-related hospitalization costs over 7 years were $453 per patient lower with ezetimibe (95% confidence interval, -$38 to -$869; P=0.030). Although all prespecified subgroups had lower cost with ezetimibe therapy, patients with diabetes mellitus, patients aged ≥75 years, and patients at higher predicted risk for recurrent ischemic events had even greater cost offsets.

Conclusions: Addition of ezetimibe to statin therapy in patients with a recent acute coronary syndrome leads to reductions in cardiovascular-related hospitalizations and associated costs, with the greatest cost offsets in high-risk patients. These cost reductions may completely offset the cost of the drug once ezetimibe becomes generic, and may lead to cost savings from the perspective of the healthcare system, if treatment with ezetimibe is targeted to high-risk patients.

Clinical trial registration: URL: https://www.clinicaltrials.gov. Unique Identifier: NCT00202878.

Keywords: IMPROVE-IT; cardiovascular hospitalization; coronary artery disease; costs; ezetimibe.