Patterns of spironolactone management following hyperkalemia among hospitalized patients with heart failure and reduced ejection fraction: a retrospective single-center study.

Background: Heart failure with reduced ejection fraction (HFrEF) is a major cause of morbidity and mortality worldwide. Hyperkalemia is a common complication of chronic spironolactone therapy and may necessitate dose reduction or discontinuation, particularly in patients with impaired renal function. This study aimed to describe real-world spironolactone management patterns following the occurrence of hyperkalemia, evaluate guideline-directed medical therapy (GDMT) exposure (receipt of ≥3 drug classes), and explore factors associated with in-hospital mortality among hospitalized patients with HFrEF and hyperkalemia receiving chronic spironolactone therapy. Methods: This retrospective single-center study included 146 adult HFrEF patients on spironolactone (May-Dec 2023). Data on demographics, comorbidities, renal function, GDMT exposure, and outcomes were extracted from electronic records. Hyperkalemia was categorized as mild-moderate (5.0-5.5 mmol/L) or severe (>5.5 mmol/L). Univariate logistic regression and multivariable Cox models identified predictors of in-hospital mortality. Kaplan-Meier analysis compared survival by GDMT exposure. Results: The study cohort ( Conclusions: In this retrospective cohort of hospitalized patients with HFrEF and hyperkalemia, spironolactone management most commonly involved dose reduction or discontinuation following hyperkalemia. Older age and chronic kidney disease were associated with higher in-hospital mortality in exploratory analyses, whereas receipt of ≥3 GDMT classes was associated with a lower adjusted hazard estimate that did not reach statistical significance. Overall, these findings are exploratory and hypothesis-generating and should be interpreted cautiously given the retrospective single-center design, the limited number of mortality events, and the potential for residual confounding.