Abstract 12797: Temporal Changes in Mortality Risk Post-Discharge After Hospitalization for Heart Failure

Importance: In observational studies, the risk for adverse events among patients admitted for heart failure (HF) is highest immediately post-discharge and declines over time. This ‘vulnerable phase’ concept has led to research and quality of care initiatives focusing primarily on early post-discharge period. However, whether this risk trajectory represents lowering of individual patient risk or changes in the population risk profile is not known. Methods: Survival and longitudinal models were used to assess temporal changes in mortality risk post-discharge in the Efficacy of Vasopressin Antagonism in Heart Failure Outcome Study With Tolvaptan (EVEREST) trial. Post hoc analysis of EVEREST included 4017 patients >18 years old discharged alive after hospitalization for HF with an ejection fraction of <40% at 359 sites from 2003-2006 and randomized to receive oral tolvaptan or placebo. Results: After a median of 9.8 months, 971 patients died (24.2%). Mortality at 1 year was 24.2%. Cumulative mortality rate declined from 15.9/100 patient-years immediately post-discharge to 13.4 at 30 days and 12.8 at 90 days; it rose steadily thereafter. The risk variation between quintiles of baseline risk was considerably larger than the temporal variation within risk strata. In a longitudinal model assessing updated mortality risk after each follow up visit, mortality risk increased during the 90 days preceding readmission and then followed a trajectory similar to the index admission. The net increase in mortality attributable to readmission was ~37%. Conclusions and Relevance: Among hospitalized HF patients, although there is a transiently elevated risk in 90 days before and after discharge, the patient’s clinical risk profile rather than temporal change remains the main determinant of mortality risk.