The influence of risk status on guideline adherence for patients with non-ST-segment elevation acute coronary syndromes

Background: Practice guidelines for patients with non-ST-segment elevation (NSTE) acute coronary syndromes (ACS) recommend targeting evidence-based therapies for the highest-risk patients. We characterized guideline adherence for NSTE ACS by risk status. Methods: We analyzed inhospital treatments and outcomes for 77 760 patients with NSTE ACS (ischemic ST-segment changes and/or positive cardiac markers) included in the CRUSADE initiative from January 2001 to September 2003 at 457 US hospitals. Compliance with the American College of Cardiology/American Heart Association Class guideline recommendations for NSTE ACS was evaluated in subgroups of eligible patients without listed contraindications at increased risk for mortality and among risk categories designated by an adapted version of the PURSUIT risk model designed to predict inhospital mortality. Results: Inhospital mortality was increased in patients with diabetes mellitus (5.8% vs 4.3%), renal insufficiency (10.0% vs 3.9%), signs of congestive heart failure on presentation (10.6% vs 3.1%), and age ≥75 years (8.6% vs 2.7%), compared with patients without these features. Use of guideline-recommended acute medications, invasive cardiac procedures, and discharge medications and interventions was significantly lower in patients with these high-risk features. Patients designated as high-risk for inhospital mortality were less likely to be treated with guideline-recommended therapies compared with low-risk and moderate-risk patients. Conclusions: Patients with NSTE ACS with the highest risk of mortality are less likely to receive guideline-recommended therapies and interventions. These findings highlight the need to clarify guideline recommendations for high-risk patients and to develop novel quality improvement approaches that target undertreated subgroups of patients with NSTE ACS.