Systematic Review of the Association Between Worsening Renal Function and Mortality in Patients With Acute Decompensated Heart Failure

Introduction: Outcomes in acute decompensated heart failure (ADHF) have remained poor. Worsening renal function (WRF) is common among patients with ADHF. However, the impact of WRF on the prognosis is controversial. We hypothesized that in patients with ADHF, the achievement of concomitant decongestion would diminish the signal for harm associated with WRF. Methods: We performed a systematic search of PubMed, EMBASE, and the Cochrane Library up to December 2019 for studies that assessed signs of decongestion in patients with WRF during ADHF admission. The primary outcome was all-cause mortality and heart transplantation. Results: Thirteen studies were selected with a pooled population of 8138 patients. During the follow-up period of 60–450 days, 19.2% of patients died. Unstratified, patients with WRF versus no WRF had a higher risk for mortality (odds ratio [OR], 1.71 [95% confidence interval {CI}, 1.45–2.01]; P < 0.0001). However, patients who achieved decongestion had a similar prognosis (OR, 1.15 [95% CI, 0.89–1.49]; P = 0.30). Moreover, patients with WRF who achieved decongestion had a better prognosis compared with those without WRF or decongestion (OR, 0.63 [95% CI, 0.46–0.86]; P = 0.004). This tendency persisted for the sensitivity analyses. Conclusions: Decongestion is a powerful effect modifier that attenuates harmful associations of WRF with mortality. Future studies should not assess WRF as an endpoint without concomitant assessment of achieved volume status.