Abstract
<title>Abstract</title> <p>Background The Naples Prognostic Score (NPS) integrates inflammatory, nutritional, and metabolic markers. Its prognostic value in critically ill patients with first acute myocardial infarction (AMI) remains underexplored. Methods This retrospective cohort study included 2003 adult patients with first-time AMI admitted to the ICU in the MIMIC-IV 3.2 database. NPS was calculated using the first available laboratory data within 24 hours of ICU admission. Patients were stratified into low-risk (NPS 0–2), moderate-risk (NPS 3), and high-risk (NPS 4) groups. The primary endpoint was 3-year all-cause mortality; the secondary endpoint was a 3-year composite of recurrent myocardial infarction or heart failure hospitalization. Multivariable Cox proportional hazards models, Kaplan–Meier survival analysis, and subgroup analyses were performed. Results High-risk patients were older, had lower hemoglobin levels, higher prevalence of chronic kidney disease, longer ICU stays, and lower rates of revascularization compared with the low-risk group (all P < 0.001). During 3-year follow-up, 3-year all-cause mortality increased progressively across NPS groups (19.7%, 31.3%, and 42.9%, respectively; log-rank P < 0.001). In the fully adjusted Cox model, high-risk patients had a 58% higher mortality risk than low-risk patients (HR 1.58, 95% CI 1.26–1.98, P < 0.001). Each 1-point increase in NPS was associated with a 49% higher risk of all-cause mortality (HR 1.49, 95% CI 1.36–1.63, P < 0.001). Significant interactions were found with hypertension, chronic kidney disease, revascularization, hemoglobin, and ICU length of stay. Similar but weaker associations were observed for the composite endpoint of recurrent myocardial infarction or heart failure hospitalization. Conclusions The NPS is a simple, readily available, and independent predictor of long-term adverse outcomes in critically ill patients with first AMI. It may serve as a practical tool for early risk stratification in the ICU setting.</p>