Patterns of angiotensin-converting enzyme inhibitor prescriptions, educational interventions, and outcomes among hospitalized patients with heart failure

Background: Among hospitalized patients with heart failure, we describe characteristics associated with prescription of angiotensin-converting enzyme (ACE) inhibitors in the doses recommended by clinical practice guidelines. We also describe the impact of ACE inhibitor prescriptions, increases in ACE inhibitor dose, and nonpharmacologic educational interventions on readmission-free survival rates. Hypothesis: We hypothesize that care by a cardiologist physician and higher mean arterial blood pressure on admission are associated with receipt of optimal ACE inhibitor doses. We hypothesize that receipt of an ACE inhibitor at discharge and an increase in ACE inhibitor dose during hospitalization are associated with superior readmission-free survival. Methods: Between January 1, 1992, and December 31, 1993, medical records were reviewed for consecutively hospitalized patients with a principal diagnosis of heart failure at an academic medical center. Documented instructions and medications prescribed at discharge were abstracted. Deaths and readmissions through December 31, 1994, were identified with the National Death Index and the study institution's administrative data base, respectively. Results: During 1992 and 1993, 387 patients were dis charged alive from hospitalization for heart failure. Among patients discharged on enalapril or captopril, 18% received doses recommended by heart failure clinical practice guidelines. Patients discharged on a recommended ACE inhibitor dose were more likely to be African-American and had lower sodium levels and higher mean arterial pressures than patients discharged on lower ACE inhibitor doses. In survival analyses, an increase in ACE inhibitor dose was associated with improved readmission-free survival, independent of left ventricular systolic function type. Receipt of an ACE inhibitor at discharge was also associated with superior readmission-free survival, while nonpharmacologic educational instructions were not associated with improved outcomes. Conclusion: Interventions are needed to improve the frequency with which ACE inhibitors are prescribed at recommended doses to hospitalized patients with heart failure. We conclude that among these patients, receipt of an ACE inhibitor at discharge and an increase in ACE inhibitor dose during hospitalization are each associated with measurable effects on readmission-free survival, while provision of educational instructions as currently practiced is not associated with better outcomes.