Predictors of prolonged hospital stay (>8 days) in acute decompensated heart failure

Background/Introduction

Acute decompensated heart failure (ADHF) is a major cause of cardiovascular hospitalization and healthcare resource utilization (1). Prolonged hospital stay is associated with increased morbidity, higher costs, and worse long-term outcomes (2). Frailty, reflecting reduced physiological reserve and systemic vulnerability, has been linked to adverse outcomes in heart failure, but its role in predicting extended hospitalization remains insufficiently defined.

Purpose

To identify clinical, laboratory, and echocardiographic predictors of prolonged hospital stay (>8 days) in patients admitted with ADHF.

Methods

We conducted an observational study including 174 consecutive patients hospitalized with ADHF. Patients were categorized according to length of stay (≤8 days vs >8 days). Baseline clinical, laboratory, and echocardiographic variables were recorded at admission. Frailty was assessed using the Clinical Frailty Scale (CFS) (4). Univariate comparisons were performed using independent samples t-tests. Multivariate logistic regression analysis included MAP, CFS, qSOFA, NYHA class, LVEF, lactate, NT-proBNP, age, and E/e’. Statistical significance was set at p < 0.05.

Results

Prolonged hospitalization (>8 days) occurred in 55 patients (31.6%). Patients with extended stay were significantly older (80.6 ± 9.7 vs 77.4 ± 9.3 years, p = 0.038) and demonstrated higher frailty burden (CFS 5.85 ± 1.51 vs 4.13 ± 1.37, p < 0.001). They also had elevated lactate (1.58 ± 0.83 vs 0.96 ± 0.56 mmol/L, p < 0.001), higher NT-proBNP levels (11,428 ± 9,252 vs 7,502 ± 8,117 pg/mL, p = 0.005), higher qSOFA scores (2.00 ± 0.88 vs 1.42 ± 0.63, p < 0.001), and more advanced NYHA class (3.07 ± 0.84 vs 2.51 ± 0.70, p < 0.001). Echocardiographic markers of elevated filling pressures were also more pronounced, including higher E/e’ ratio (16.04 ± 3.68 vs 14.20 ± 3.25, p = 0.001) and higher tricuspid regurgitation velocity (2.93 ± 0.41 vs 2.79 ± 0.40 m/s, p = 0.042). No significant differences were observed in LVEF, LVEDD, sodium, bicarbonate, creatinine, MAP, LAVi, or TAPSE.

In multivariate analysis, frailty (OR 2.18 per 1-point increase, p < 0.001) and lactate (OR 2.34, p = 0.016) remained independent predictors of prolonged hospitalization, whereas age, NYHA class, NT-proBNP, qSOFA, LVEF, MAP, and E/e’ lost statistical significance.

Conclusion

Frailty and elevated lactate levels are strong and independent determinants of prolonged hospital stay in acute decompensated heart failure. Routine frailty assessment may enhance early identification of patients at risk for extended hospitalization and support targeted clinical management.Table1 . Univariate AnalysisMultivariate analysis