Both in- and out-hospital worsening of renal function predict outcome in patients with heart failure: results from the Coordinating Study Evaluating Outcome of Advising and Counseling in Heart Failure (COACH).

AIMS: The effect of worsening renal function (WRF) after discharge on outcome in patients with heart failure is unknown. METHODS AND
RESULTS: We assessed estimated glomerular filtration rate (eGFR) and serum creatinine at admission, discharge, and 6 and 12 months after discharge, in 1023 heart failure patients. Worsening renal function was defined as an increase in serum creatinine of >26.5 micromol/L and >25%. The primary endpoint was a composite of all-cause mortality and heart failure admissions. The mean age of patients was 71 +/- 11 years, and 62% was male. Mean eGFR at admission was 55 +/- 21 mL/min/1.73 m(2). In-hospital WRF occurred in 11% of patients, while 16 and 9% experienced WRF from 0 to 6, and 6 to 12 months after discharge, respectively. In multivariate landmark analysis, WRF at any point in time was associated with a higher incidence of the primary endpoint: hazard ratio (HR) 1.63 (1.10-2.40), P = 0.014 for in-hospital WRF, HR 2.06 (1.13-3.74), P = 0.018 for WRF between 0-6 months, and HR 5.03 (2.13-11.88), P < 0.001 for WRF between 6-12 months.
CONCLUSION: Both in- and out-hospital worsening of renal function are independently related to poor prognosis in patients with heart failure, suggesting that renal function in heart failure patients should be monitored long after discharge.