Worsening renal function at 1 year after acute heart failure

Background While in-hospital worsening renal function (WRF) during acute heart failure (AHF) management has been extensively studied, the association between post-discharge WRF and subsequent clinical outcome remains poorly understood. Purpose To investigate (1) the prevalence and determinants of WRF at 1 year after discharge (1Y-WRF), (2) the subsequent prognostic impact of 1Y-WRF, and (3) whether certain characteristics of clinical concern (e.g., left ventricular ejection fraction [LVEF], post-discharge heart failure [HF] trajectory, baseline renal function, comorbidities, treatment strategies) potentially affect its prognostic association in patients with AHF. Methods Data were analyzed for 1,753 patients hospitalized with AHF from a multicenter registry with available estimated glomerular filtration rate (eGFR) measurements at discharge and 1 year after discharge. 1Y-WRF was defined as a ≥25% decrease in eGFR during the first year. The primary endpoint was a composite of all-cause mortality and HF rehospitalization beyond 1 year after discharge. Exploratory subgroup analyses were conducted based on age (<80, ≥80 years), sex, LVEF (<50%, ≥50%), diabetes, eGFR (<45, ≥45 mL/min/1.73 m²), HF rehospitalization within 1 year, anemia, and the use of renin-angiotensin-aldosterone system inhibitors at 1 year. Results Of the 1,753 patients (median age 76 years, 39.9% female, median eGFR 50.7 mL/min/1.73 m² at discharge), 285 (16.3%) developed 1Y-WRF. Female sex, anemia, higher New York Heart Association class, and higher eGFR at discharge were independently associated with 1Y-WRF. The median follow-up period after discharge was 730 (643–1,079) days. The number of events occurring beyond 1 year after discharge was 358 for the composite endpoint, 196 for all-cause mortality, and 217 for HF rehospitalization. 1Y-WRF was associated with an increased risk of the subsequent composite endpoint (adjusted hazard ratio [HR]: 1.34, 95% confidence interval [CI]: 1.02–1.75, P = 0.035), primarily driven by HF rehospitalization (adjusted sub-distribution HR: 1.57, 95% CI: 1.11–2.21, P = 0.010). Subgroup analyses demonstrated that the prognostic impact was greater in younger patients, those with lower LVEF, higher eGFR, and no HF rehospitalization within 1 year (figure 1). Conclusions WRF after discharge was relatively common in a contemporary cohort of patients with AHF, and was associated with subsequent worse clinical outcomes, albeit its association varied depending on age, baseline cardiac and renal functions, and post-discharge HF worsening. Further research is required to create more individually tailored disease management strategies in these patients.