The relationship between transient and persistent worsening renal function and mortality in patients with acute...

Worsening renal function (WRF) is an ominous complication in patients with acute heart failure syndrome (AHFS). Few data are available with regard to the clinical implications of transient versus persistent WRF in this setting.

We studied 467 patients with AHFS and creatinine measurements at baseline and on days 2, 5, 14, and 30. WRF (>/= 0.5 mg/dL increase in serum creatinine above baseline at any time point) was defined as persistent when serum creatinine remained >/= 0.5 mg/dL above baseline throughout day 30, and transient when creatinine levels subsequently decreased to < 0.5 mg/dL above baseline. WRF occurred in 115 patients, and was transient in 39 patients (33.9%). The 6-month mortality rates were 17.3%, 20.5%, and 46.1% in patients without WRF, transient WRF, and persistent WRF, respectively. In a multivariable Cox model, compared with patients with stable renal function, the adjusted hazard ratio for mortality was 0.8 (95% CI 0.4-1.7; P = .58) in patients with transient WRF and 3.2 (95% CI 2.1-5.0; P < .0001) in patients with persistent WRF.

Transient WRF is frequent among patients with AHFS. Whereas persistent WRF portends increased mortality, transient WRF appears to be associated with a better outcome as compared with persistent renal failure.