Background: Although the absolute benefits of an intervention are proportional to patients' underlying risk, studies in heart failure have noted a paradoxical inverse relationship between treatment and risk. The extent to which this reflects higher rates of contraindications in patients with higher risk or larger gaps in care quality has not been explored.
Methods and results: We studied 18 307 patients with left ventricular systolic dysfunction surviving hospitalization between January 2005 and June 2007 from 194 hospitals participating in Get With The Guidelines (GWTG)-Heart Failure. Patients were categorized according to their estimated risk for in-hospital mortality using a validated risk score. The proportions of patients with documented contraindications to angiotensin-converting enzyme inhibitors or angiotensin receptor blockers and beta-blockers as well as the use of these medications among patients without contraindications at hospital discharge was determined across levels of risk. For each therapy, the proportion of patients with contraindications was significantly higher with increasing patient risk (P<0.001 for each). Even after excluding those with contraindications, the use of angiotensin-converting enzyme inhibitors/angiotensin receptor blockers and beta-blockers was significantly lower with increasing risk (P<0.001 for each).
Conclusions: The use of evidence-based therapies is lower in patients with heart failure at higher risk of mortality both because of higher rates of contraindications to therapy and lower rates of use among eligible patients. Optimizing heart failure outcomes will require both the expansion of the evidence base for treating the highest-risk patients as well as the development of effective strategies to assure that eligible high-risk patients receive all appropriate therapies.