Kidney Outcomes Among Medicare Beneficiaries After Hospitalization for Heart Failure

Importance Kidney health has received increasing focus as part of comprehensive heart failure (HF) treatment efforts. However, the occurrence of clinically relevant kidney outcomes in contemporary populations with HF has not been well studied. Objective To examine rates of incident dialysis and acute kidney injury (AKI) among Medicare beneficiaries after HF hospitalization. Design, Setting, and Participants This retrospective cohort study evaluated adults aged 65 years or older who were hospitalized for HF across 372 sites in the Get With The Guidelines–Heart Failure registry in the US between January 1, 2014, and December 31, 2018. Patients younger than 65 years or requiring dialysis either during or prior to hospitalization were excluded. Data were analyzed from May 4, 2021, to March 8, 2024. Main Outcomes and Measures The primary outcome was inpatient dialysis initiation in the year after HF hospitalization and was ascertained via linkage with Medicare claims data. Other all-cause and cause-specific hospitalizations were also evaluated. The covariate-adjusted association between discharge estimated glomerular filtration rate (eGFR) and 1-year postdischarge outcomes was examined using Cox proportional hazards regression models. Results Overall, among 85 298 patients included in the analysis (mean [SD] age, 80 [9] years; 53% women) mean (SD) left ventricular ejection fraction was 47% (16%) and mean (SD) eGFR was 53 (29) mL/min per 1.73 m 2 ; 54 010 (63%) had an eGFR less than 60 mL/min per 1.73 m 2 . By 1 year after HF hospitalization, 6% had progressed to dialysis, 7% had progressed to dialysis or end-stage kidney disease, and 7% had been readmitted for AKI. Incident dialysis increased steeply with lower discharge eGFR category: compared with patients with an eGFR of 60 mL/min per 1.73 m 2 or more, individuals with an eGFR of 45 to less than 60 and of less than 30 mL/min per 1.73 m 2 had higher rates of dialysis readmission (45 to <60: adjusted hazard ratio [AHR], 2.16 [95% CI, 1.86-2.51]; <30: AHR, 28.46 [95% CI, 25.25-32.08]). Lower discharge eGFR (per 10 mL/min per 1.73 m 2 decrease) was independently associated with a higher rate of readmission for dialysis (AHR, 2.23; 95% CI, 2.14-2.32), dialysis or end-stage kidney disease (AHR, 2.34; 95% CI, 2.24-2.44), and AKI (AHR, 1.25; 95% CI, 1.23-1.27), with similar findings for all-cause mortality, all-cause readmission, and HF readmission. Baseline left ventricular ejection fraction did not modify the covariate-adjusted association between lower discharge eGFR and kidney outcomes. Conclusions and Relevance In this study, older adults with HF had substantial risk of kidney complications, with an estimated 6% progressing to dialysis in the year after HF hospitalization. These findings emphasize the need for health care approaches prioritizing kidney health in this high-risk population.