The A-HARDEST-CAMP score: A 12-parameter tool for predicting prolonged hospitalization in acute heart failure

Prolonged hospitalization in patients admitted with acute decompensated heart failure (HF) is associated with worse clinical outcomes, higher readmission risk, and increased healthcare costs. Early identification of patients at risk for extended hospital stay may help guide clinical decisions and improve the use of inpatient resources.

To develop and evaluate the A-HARDEST-CAMP score, an admission-based tool designed to predict prolonged hospitalization (>6 days) in patients hospitalized with decompensated HF.

This retrospective study included 4696 patients hospitalized with decompensated HF between 2016 and 2023, after predefined exclusions and removal of in-hospital deaths as a competing event. Prolonged hospitalization was defined as a length of stay greater than 6 days, corresponding to the cohort median. Independent predictors were identified using multivariable logistic regression. Age and NT-proBNP were modeled as continuous variables in the primary model, with log-transformed NT-proBNP and an interaction term for atrial fibrillation. A simplified 12-component score (A-HARDEST-CAMP) was then derived using clinically practical thresholds for bedside use. Model performance was assessed using discrimination and calibration metrics with bootstrap internal validation (B = 1000).

The primary multivariable prediction model demonstrated excellent discrimination, with an apparent AUC of 0.875 (95 % CI 0.865-0.885) and an optimism-corrected AUC of 0.873 after bootstrap validation. Calibration was good (intercept -0.0027, slope 0.990; Brier score 0.139). A simplified integer-based scoring system (A-HARDEST-CAMP) was derived for clinical use and demonstrated good discrimination (AUC 0.795, 95 % CI 0.782-0.808). Renal dysfunction, elevated C-reactive protein, advanced age, prior HF hospitalization, and elevated NT-proBNP showed the strongest associations with prolonged hospitalization.

The A-HARDEST-CAMP score is a practical and interpretable tool for early risk stratification in acute HF. Using routinely available admission data, it may facilitate early triage, discharge planning, and more efficient allocation of inpatient healthcare resources.