LAUSR

BACKGROUND Few contemporary data exist evaluating care patterns and outcomes in HF across the spectrum of kidney function. OBJECTIVES To characterize differences in quality of care and outcomes in patients hospitalized for HF by degree of kidney dysfunction. METHODS We evaluated quality metrics among patients hospitalized with HF at 418 sites in the GWTG-HF registry from 2014-2019 by discharge CKD-EPI-derived eGFR. We additionally evaluated the risk-adjusted association of admission eGFR with in-hospital mortality. RESULTS Among 365,494 hospitalizations (age 72±15y, LVEF 43±17%), median discharge eGFR was 51(34-72) mL/min/1.73m2, 234,332 (64%) had eGFR<60 mL/min/1.73m2, and 18,869 (5%) were on dialysis. eGFR distribution remained stable from 2014-2019. Among 157,439 patients with HFrEF(≤40%), discharge guideline-directed medical therapies, including β-blockers, were lowest in discharge eGFR<30 mL/min/1.73m2 or dialysis (P<0.001). "Triple therapy" with ACE inhibitor/ARB/ARNI+β-blocker+MRA was used in 38%, 33%, 25%, 15%, 5%, and 3% for eGFR ≥90, 60-89, 45-59, 30-44, <30 mL/min/1.73m2 and dialysis, respectively; P<0.001. Mortality was higher in a graded fashion at lower admission eGFR groups (1.1%, 1.5%, 2.0%, 3.0%, 5.0%, and 4.2%, respectively; P<0.001). Steep covariate-adjusted associations between admission eGFR and mortality were observed across EF subgroups, but was slightly stronger in HFrEF compared with HF with mid-range or preserved EF (Pinteraction=0.045). CONCLUSION Despite facing elevated risks of mortality, patients with comorbid HFrEF and kidney disease are not optimally treated with evidence-based medical therapies, even at levels of eGFR where such therapies would not be contraindicated by kidney dysfunction. Further efforts are required to mitigate risk in comorbid HF and kidney disease.