The Prognostic Impact of Renal Function Decline during Hospitalization for Heart Failure.

Introduction: We aimed to evaluate the prognostic impact of renal insufficiency and fluctuation of glomerular filtration observed during hospitalization for heart failure (HF).

Methods: We followed 3,639 patients hospitalized for acute HF and assessed the mortality risk associated with moderate or severe renal insufficiency, either permanent or transient.

Results: After adjustment, severe renal failure defined as estimated glomerular filtration (eGFR) <30 mL/min indicates ≈60% increase in 5-year mortality risk. Similar risk also had patients with only transient decline of eGFR to this range. In contrast, we did not observe any apparent mortality risk attributable to mild/moderate renal insufficiency (eGFR 30-59.9 mL/min), regardless of whether it was transient or permanent.

Conclusion: Even transient severe renal failure during hospitalization indicates poor long-term prognosis of patients with manifested HF. In contrast, only moderate renal insufficiency observed during hospitalization has no additive long-term mortality impact.