Racial Differences in Cardiac Revascularization Rates: Does “Overuse” Explain Higher Rates among White Patients?

Racial Differences in Cardiac Revascularization Rates: Does “Overuse” Explain Higher Rates among White Patients?

From Brigham and Women's Hospital, Harvard School of Public Health, and Massachusetts General Hospital, Boston, Massachusetts; and Brown University, Providence, Rhode Island.

Abstract

Background: Coronary artery bypass graft (CABG) surgery and percutaneous transluminal coronary angioplasty (PTCA) are well-established treatments for symptomatic coronary artery disease. Previous studies have documented racial differences in rates of use of these cardiac revascularization procedures. Other studies suggest that these procedures are overused: that is, they are done for patients with clinically inappropriate indications.

Objective: To test the hypothesis that the higher rate of cardiac revascularization among white patients is associated with a higher prevalence of overuse (revascularization for clinically inappropriate indications) among white patients than among African-American patients.

Design: Observational cohort study using Medicare claims and medical record review.

Setting: 173 hospitals in five U.S. states.

Participants: A stratified, weighted, random sample of 3960 Medicare beneficiaries who underwent coronary angiography during 1991 and 1992; 1692 of these patients underwent 1711 revascularization procedures within 90 days.

Measurements: The proportion of CABG and PTCA procedures rated appropriate, uncertain, and inappropriate according to RAND criteria, and the multivariate odds of undergoing inappropriate revascularization among African-American patients and white patients.

Results: After angiography, rates of PTCA (23% vs. 19%) and CABG surgery (29% vs. 17%) were significantly higher among white patients than among African-American patients. The respective rates of inappropriate PTCA and CABG surgery were 14% and 10%. Among the study states, rates of inappropriate use ranged from 4% to 24% for PTCA and 0% to 14% for CABG surgery. White patients were more likely than African-American patients to receive inappropriate PTCA (15% vs. 9%; difference, 6 percentage points [95% CI, −0.4 to 12.7 percentage points]), and difference by race was statistically significant among men (20% vs. 8%; difference, 12 percentage points [CI, 1.2 to 21.7 percentage points]). Rates of inappropriate CABG surgery did not differ by race (10% in both groups).

Conclusions: Among a large and diverse sample of Medicare beneficiaries in five U.S. states, overuse of PTCA was greater among white men than among other groups, but this difference did not fully account for racial disparities in revascularization. Overuse of cardiac revascularization varied significantly by geographic region.

Article and Author Information

Acknowledgments: The authors thank David Bates for comments on an earlier version of the manuscript; Margaret Volya and Jie Zheng for programming assistance; Marissa Hendrickson and Andrew Ellner for assistance with data collection; Marian Hendershot and the staff of the participating Peer Review Organizations, without whom this project would not have been possible; and Jeffrey Adams and Anne Hudson for assistance in preparing the manuscript.
Grant Support: By grant 5-RO-HS07098-02S1 from the Agency for Health Care Policy and Research.
Requests for Single Reprints: Eric C. Schneider, MD, MSc, Department of Health Policy and Management, Harvard School of Public Health, 677 Huntington Avenue, Boston, MA 02115.
Current Author Addresses: Drs. Schneider, Leape, and Epstein: Department of Health Policy and Management, Harvard School of Public Health, 677 Huntington Avenue, Boston, MA 02115.
Dr. Weissman: Institute for Health Policy, Massachusetts General Hospital, 50 Staniford Street, 9th Floor, Boston, MA 02115.
Dr. Piana: Division of Cardiology, Vanderbilt University Medical Center, 2311 Pierce Avenue, Nashville, TN 37232-8802.
Dr. Gatsonis: Center for Statistical Sciences, Brown University Box G-H, 167 Angell Street, 2nd Floor, Providence, RI 02912.
Author Contributions: Conception and design: E.C. Schneider, L.L. Leape, J.S. Weissman, C. Gatsonis, A.M. Epstein.
Analysis and interpretation of the data: E.C. Schneider, L.L. Leape, J.S. Weissman, R.N. Piana, C. Gatsonis, A.M. Epstein.
Drafting of the article: E.C. Schneider, J.S. Weissman, A.M. Epstein.
Critical revision of the article for important intellectual content: E.C. Schneider, L.L. Leape, J.S. Weissman, R.N. Piana, C. Gatsonis, A.M. Epstein.
Final approval of the article: E.C. Schneider, L.L. Leape, J.S. Weissman, C. Gatsonis, A.M. Epstein.
Statistical expertise: C. Gatsonis.
Obtaining of funding: C. Gatsonis, A.M. Epstein.
Administrative, technical, or logistic support: E.C. Schneider, A.M. Epstein.
Collection and assembly of data: E.C. Schneider, J.S. Weissman, R.N. Piana, A.M. Epstein.