What does this research mean for the field?

Low diuretic efficiency (DE) is associated with worsened survival in heart failure patients, with hazard ratios of 1.36 in the Penn cohort and 2.86 in the ESCAPE cohort. Novelty: ClaimNovelty.NOVEL_FINDING. Consensus alignment: ConsensusAlignment.CHALLENGES_CONSENSUS.

December 31, 2013Open Access

Loop Diuretic Efficiency

Key Result

Low diuretic efficiency (DE) was associated with worsened survival in heart failure patients, with HRs of 1.36 in Penn and 2.86 in ESCAPE cohorts.

Structured PICO

Does low diuretic efficiency predict worsened survival in patients hospitalized with acute decompensated heart failure?

Population

1,047 patients hospitalized with acute decompensated heart failure across two cohorts: the Penn retrospective cohort (n=657, BNP >100 pg/mL, received IV loop diuretics) and the ESCAPE trial cohort (n=390, EF ≤30%, SBP ≤125 mmHg, prior HF hospitalization, on >160 mg furosemide equivalents daily).

Intervention

Low diuretic efficiency (DE), defined as net fluid output produced per 40 mg of furosemide equivalents below the median value (Penn median: 480 mL; ESCAPE median: 148 mL).

Comparator

High diuretic efficiency (DE above the median value).

Outcome

All-cause mortality (ascertained at median 5.1 years for Penn cohort and 180 days for ESCAPE cohort).hard clinical

Main Result

Absolute Event Rate: 0% vs 0%

Abstract

Background— Rather than the absolute dose of diuretic or urine output, the primary signal of interest when evaluating diuretic responsiveness is the efficiency with which the kidneys can produce urine after a given dose of diuretic. As a result, we hypothesized that a metric of diuretic efficiency (DE) would capture distinct prognostic information beyond that of raw fluid output or diuretic dose. Methods and Results— We independently analyzed 2 cohorts: (1) consecutive admissions at the University of Pennsylvania (Penn) with a primary discharge diagnosis of heart failure (n=657) and (2) patients in the Evaluation Study of Congestive Heart Failure and Pulmonary Artery Catheterization Effectiveness (ESCAPE) data set (n=390). DE was estimated as the net fluid output produced per 40 mg of furosemide equivalents, then dichotomized into high versus low DE based on the median value. There was only a moderate correlation between DE and both intravenous diuretic dose and net fluid output (r 2 ≤0.26 for all comparisons), indicating that DE was describing unique information. With the exception of metrics of renal function and preadmission diuretic therapy, traditional baseline characteristics, including right heart catheterization variables, were not consistently associated with DE. Low DE was associated with worsened survival even after adjusting for in-hospital diuretic dose, fluid output, in addition to baseline characteristics (Penn: hazards ratio HR, 1.36; 95% confidence interval CI, 1.04−1.78; P =0.02; ESCAPE: HR, 2.86; 95% CI, 1.53−5.36; P =0.001). Conclusions— Although in need of validation in less-selected populations, low DE during decongestive therapy portends poorer long-term outcomes above and beyond traditional prognostic factors in patients hospitalized with decompensated heart failure.