Time to first intravenous loop diuretic and outcomes in acute decompensated heart failure: a retrospective cohort study
I Moseley, A CorreaAbstract
Background/Introduction
Intravenous loop diuretics are foundational therapy for acute decompensated heart failure (ADHF), yet delays in treatment may reflect modifiable system-level factors.
Purpose
To evaluate the association between time to first intravenous loop diuretic administration and in-hospital outcomes among adults admitted with ADHF.
Methods
We conducted a retrospective cohort study using the MIMIC-IV v3.1 database (PhysioNet). Adult hospital admissions with ADHF, identified using ICD-9 (428.x) or ICD-10 (I50.x) diagnosis codes, were included if an intravenous loop diuretic was administered within 24 hours of admission. The exposure was time from admission to first intravenous loop diuretic, analysed in prespecified strata (≤2 h, 2–6 h, 6–12 h, >12 h). The primary outcome was in-hospital mortality. The secondary outcome was hospital length of stay. Multivariable regression models adjusted for age and sex.
Results
The cohort included 23,232 admissions. Median time to first intravenous loop diuretic was 350 minutes (interquartile range 205–794). Overall in-hospital mortality was 5.9%. Compared with initiation within ≤2 hours, initiation after >12 hours was not associated with in-hospital mortality (adjusted odds ratio 1.03, 95% confidence interval 0.82–1.29). Longer time to treatment was associated with increased hospital length of stay: adjusted length-of-stay ratios versus ≤2 hours were 1.12 (95% confidence interval 1.08–1.17) for 2–6 hours, 1.18 (95% confidence interval 1.13–1.23) for 6–12 hours, and 1.20 (95% confidence interval 1.15–1.25) for >12 hours.
Conclusion(s)
In a large real-world cohort of adults hospitalised with ADHF, delayed initiation of intravenous loop diuretics was associated with longer hospital length of stay but not higher in-hospital mortality after adjustment. These findings support time to diuretic initiation as a potential quality-of-care metric and motivate further evaluation of strategies to reduce treatment delays.For image description, please refer to the figure legend and surrounding text.