Real-World Intravenous Diuretic Use to Treat Congestion in Patients With Heart Failure　― An Observational Study Using a Research Database ―

Background: Intravenous (IV) diuretics are key in the treatment of acute heart failure, but the time of administration can affect outcomes. Using a medical database, we assessed the real-world usage and clinical impact of IV diuretics after admission. Methods and Results: This observational study included hospitalized patients with heart failure who received IV diuretics. Relationships between IV diuretic use and clinical outcomes (duration of hospitalization, in-hospital mortality, readmission) were evaluated using analysis of variance or logistic regression. Overall, 9,653 patients (51.1% male) were assessed (mean age 80.9 years). Most (89.1%) patients had IV loop diuretic treatment initiated on Day 1 of hospitalization and 68.0% achieved the maximum dose on that day. The median duration of hospitalization was 17.0 days. In-hospital mortality was 9.2%; 13.7% of patients were readmitted within 3 months after discharge. There were prognostic relationships between IV diuretic usage and both duration of hospitalization and in-hospital mortality. On multivariable analysis, the time of maximum dose had the biggest impact on outcomes. Duration of hospitalization was prolonged and in-hospital mortality rates increased when the time of maximum dose was delayed. There was little correlation between IV diuretic use and readmission following discharge. Conclusions: Short-term outcomes (duration of hospitalization, in-hospital mortality) correlated with the time of maximum IV diuretic dose; thus, early initiation and subsequent modification of appropriate congestion treatment is critical for prognostic improvement.