Changes in geographic variation in the use of percutaneous coronary intervention for stable ischemic heart disease after publication of the Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation (COURAGE) trial.

BACKGROUND: Clinical uncertainty is cited as a cause of geographic variation. However, little is known about the effect of comparative effectiveness research on variation. We examined whether geographic variation in the use of percutaneous coronary intervention (PCI) for stable ischemic heart disease (SIHD) declined after publication of the Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation (COURAGE) trial. METHODS AND
RESULTS: We examined changes in utilization and geographic variation in 67 hospital referral regions using the State Inpatient Databases. We compared age- and sex-adjusted rates of PCI for SIHD before (2006) and after (2008) publication of the COURAGE trial and compared those with contemporaneous changes in PCI volume for acute coronary syndrome. A total of 272,659 PCIs for SIHD from 526 hospitals were included in the analysis. After the publication of the COURAGE trial, PCI volume for SIHD declined by 25% (P<0.001) and decreased by 12% for acute coronary syndrome (P<0.001). This was predominantly attributable to changes in hospital referral regions with the highest levels of utilization pre-COURAGE trial (35% decline in the highest tertile versus 18% in the lowest). As measured by the systematic component of variation, there was substantial geographic variation in the use of PCI for SIHD preceding the publication of the COURAGE trial. Variation declined by 28% (0.53 versus 0.40) after publication, but geographic variation remained higher for SIHD than acute coronary syndrome (0.40 versus 0.17).
CONCLUSIONS: There was a substantial decline in the use of and geographic variation in PCI for SIHD after the publication of the COURAGE trial. However, geographic variation in the use of PCI for SIHD remained high.