Associations Between Admission C-Reactive Protein and In-Hospital Mortality Amongst Patients with Cardiogenic Shock

BACKGROUND AND AIMS: Systemic inflammation in cardiogenic shock is associated with increased disease severity and mortality. C-reactive protein (CRP) is a widely accessible inflammatory biomarker that may aid phenotyping and risk stratification. We evaluated the association between admission CRP and in-hospital mortality in patients with cardiogenic shock. METHODS: Using a multicentre, nationally representative database, we identified adults with a discharge diagnosis of cardiogenic shock from 2015-2023 who had CRP measured within two days of hospital admission; patients with sepsis were excluded. CRP was analysed in tertiles. Inverse probability weighting (IPW) was used to assess associations with in-hospital mortality. Secondary outcomes included ICU and hospital length of stay and total cost. RESULTS: We identified 26,525 patients; median (IQR) CRP was 18.4 mg/L (5.0-67.0 mg/L). In-hospital mortality was 28.7%, 32.7%, and 42.3% across tertiles 1-3. In-hospital mortality increased by 19% for each 50-unit increase in CRP (OR 1.19; 95% CI: 1.16-1.21, p<0.001). After IPW, tertiles 2 and 3 had higher absolute mortality risks compared with tertile 1 by 3.9% (95% CI: 2.4%-5.3%) and 12.4% (95% CI: 10.9%-13.9%), respectively (both, p<0.001). Findings were consistent in sensitivity analyses restricted to day-1 CRP measurement, primary diagnoses of heart failure or myocardial infarction, and among patients requiring early mechanical circulatory support (all, p<0.05). Median ICU and hospital stay increased significantly across tertiles (all, p<0.001), total cost was not statistically different. CONCLUSIONS: In patients with cardiogenic shock, a readily available biomarker, elevated CRP was associated with higher in-hospital mortality.