Clinical and Economic Effects of Coronary Restenosis After Percutaneous Coronary Intervention in a Managed Care Population

by
This study is the first to estimate costs and medical resource use associated with restenosis involving bare metal stents in managed care percutaneous coronary intervention patients.
Mary Ann Clark, MHA
Department of Health Economics and Outcomes Research, Boston Scientific Corp., Natick, Mass.

ABSTRACT

Purpose: The epidemiology of coronary restenosis after percutaneous coronary intervention (PCI) has been documented extensively in clinical trials, but no data exist on the clinical and economic burden of restenosis in a managed care population.

Design: Retrospective cohort with a nationally representative managed care claims database (IHCIS, Waltham, Mass.) representing 2.8 million members.

Methodology: Patients undergoing initial PCI between 1/1/00 and 12/31/00 (N=3,258) were identified and followed to 1 year. Clinical events, resource use, and costs between 1 month and 1 year after the initial PCI were identified. The clinical restenosis rate was estimated by multiplying the observed repeat revascularization rate by 0.85, based on previously published studies. All costs are reported from a managed care perspective in Year 2000 dollars.

Principal findings: Overall, 14.7 percent of patients required 1 or more repeat revascularization procedures between 1 month and 1 year after initial PCI, which implies an estimated clinical restenosis rate of 12.5 percent. Mean 1-year costs were nearly 6-fold higher among patients with and without repeat revascularization ($31,954 ± $31,857 vs. $5,474 ± $12,006, P<.001). After adjusting for baseline imbalances, the independent incremental cost for each patient with repeat revascularization was $24,955 (95 percent confidence interval, $23,401-$26,510). Annual follow-up costs attributable to restenosis were $3,118 per initial PCI recipient (i.e., $24,955 × 12.5 percent).

Conclusion: Clinical restenosis occurred in approximately 12.5 percent of real-world managed care PCI patients and increased health care costs by an average of $3,118 per patient. These findings have important implications for the cost-effectiveness of new treatments that substantially reduce restenosis.

Key terms: restenosis, stent, cost-effectiveness, managed care, costs, epidemiology

This study was made possible through a grant from Boston Scientific Corp.

Mary Ann Clark, MHA, and Elise M. Pelletier, MS, are employees and shareholders in Boston Scientific Corp. Ameet Bakhai, MD, and David J. Cohen, MD, MSc, are paid consultants for Boston Scientific Corp.