Early intravenous heart failure therapy and outcomes among older patients hospitalized for acute decompensated heart failure: findings from the Acute Decompensated Heart Failure Registry Emergency Module (ADHERE-EM).

Background: Timing of initial treatment for acute decompensated heart failure (ADHF) varies across hospitals and its impact on outcomes remains poorly defined. We examined the association between time to first intravenous (IV) heart failure (HF) therapy and patient outcomes.

Methods: Using the ADHERE-EM linked to Medicare claims data, we identified patients ≥65 years old who were hospitalized for ADHF and received IV HF therapy during index admission. Cox proportional hazard model was used to assess the association of time to treatment with a composite of 30-day all-cause mortality or re-admission. Generalized linear mixed models were used to examine the association of time to treatment with in-hospital all-cause mortality, index hospitalization length of stay, and total days alive and out-of-hospital at 30 days.

Results: Of 6,971 patients, the median time to first IV HF therapy was 2.3-hours (interquartile range 1.1, 4.4). The cumulative incidence of 30-day all-cause mortality or readmission was 27.4%. After adjusting for covariates, time to treatment was not associated with increased risk of composite 30-day all-cause mortality or re-admission (HR 1.00; 95% CI 1.00-1.00; P = .221). However, every hour delay in treatment was associated with a modest increased risk of in-hospital mortality (adjusted OR 1.01; 95% CI 1.00-1.02; P = .001) and an approximately 1.4-hour increase in index admission length of stay (P < .001).

Conclusion: Among older patients presenting with ADHF, delay in initiating IV HF therapy was associated with modestly higher risk for in-hospital mortality and longer length of stay, but was not associated with 30-day outcomes.