Prior studies have documented that patients' health insurance status can impact use of guideline-based care as well as acute outcomes for coronary artery disease. Whether insurance status remains a contemporary influence among centers participating in a national quality improvement initiative is unknown.

We analyzed data from 237,779 admissions with coronary artery disease from 527 hospitals participating in the Get With The Guidelines-Coronary Artery Disease Program from 2000 to 2008. Insurance status was Medicare (48.8%), Private/Health Maintenance Organization (HMO) (34.9%), Medicaid (8.2%), and No Insurance Documented (NID) (8.2%). Quality of care was measured using standard quality indicators covering acute treatment and discharge measures, utilization of invasive procedures, length of stay, and mortality. Relationship between different insurance types was examined using generalized estimating equation logistic regression and propensity-score matching adjusting for demographics, comorbidities and hospital characteristics.

After propensity matching, full compliance with all eligible measures (deficit-free care) relative to Private/HMO was lower for Medicare (P < .0001) and Medicaid (P < .0001) and higher for the NID group (P = .0312). The acute reperfusion times were comparable among the groups. Compared with the Private/HMO group, all three groups had higher generalized estimating equation–adjusted mortality (OR, 1.15; 95% CI, 1.08-1.21; P < .001; OR, 1.18; 95% CI, 1.09-1.29; P < .001 and OR, 1.13; 95% CI, 1.01-1.25; P = .026), for Medicare, Medicaid, and NID, respectively. After propensity matching, mortality for Medicare was similar (P = .1197) and higher for NID (P = .0015) and Medicaid (P = .0015) groups.

These findings suggest that among centers participating in a national quality improvement initiative patient insurance status may be associated with differences in cardiovascular care and outcomes.