Objective:

To develop and validate a novel risk score model of multimorbidity for heart failure (HF) risk stratification, emphasizing the significance of gut microbiome factors in improving predictive accuracy.

Key Findings:

• The final 11-variable risk model demonstrated a diagnostic performance of 0.71 in the training cohort and 0.70 in the validation cohort (P < 0.001), incorporating gut microbiome factors.
• The risk score effectively stratified patients, with higher risk groups showing a significantly increased incidence of death or rehospitalization (P < 0.001).
• The model integrates gut microbiome factors alongside traditional HF risk factors, enhancing its predictive capability.

Interpretation:

The developed risk model offers a more comprehensive assessment of HF risk by integrating multimorbidity and gut microbiome factors, which are often overlooked in existing risk scores, potentially guiding clinical decision-making.

Limitations:

• The study was conducted using two specific cohorts, which may limit generalizability; future studies should aim for diverse populations.
• Exclusion of patients due to sample unavailability could introduce bias; strategies to minimize this in future research should be considered.

Conclusion:

A novel risk model and score for HF patients was developed, underscoring the importance of multimorbidity and gut microbiome factors in predicting rehospitalization and mortality, with implications for clinical practice.