Diuretic resistance measured by sodium excretion and urine output in acute heart failure: The DIURESIS-AHF study

The dynamics and prognostic value of diuretic metrics in response to initial intravenous (IV) diuretic therapy in patients with acute heart failure (AHF) remain unclear. We assessed the association between urinary sodium concentration, diuretic response (DR) following IV furosemide administration, and their prognostic implications in patients with AHF.

The diuretic resistance measured by sodium excretion and urine output (DIURESIS)-AHF study was a prospective, multicenter, observational study that assessed spot urinary sodium concentrations at 0/1/2 h, total urine output, and urinary sodium excretion achieved within the first 6 h following initial IV furosemide administration. The DR was measured using the urine output or sodium excretion per 40 mg of IV furosemide.

Ninety-six patients with AHF (mean age, 78 years; men, 56 %) were included. Urine sodium concentrations at 1/2 h showed high inter- and intra-patient variabilities. A lower DR based on 6-h sodium excretion was independently associated with a higher incidence of composite outcome, even after adjusting for known risk factors (/10-mmol increase; hazard ratio: 0.96, 95 % confidence interval: 0.93-0.99, p = 0.011); the DR measured by urine output was not.

Urine sodium concentrations at 1/2 h after initial IV furosemide showed great inter- and intra-patient variabilities, and lower DR using 6-h sodium excretion after IV furosemide was associated with a poor prognosis in patients with AHF.