Beyond first-day biomarkers: The critical role of peak cardiac troponin I in sepsis prognosis.

Background: Sepsis is a global health challenge with high mortality rates. It demands timely risk identification and biomarker-based strategies to optimize ICU management and outcomes.

Objective: To explore the prognostic value of cardiac troponin I (cTnI) and B-type natriuretic peptide (BNP) in predicting 28-day mortality in septic patients.

Methods: We analyzed clinical data of septic ICU patients at Shanghai General Hospital. We used Cox models and ROC curves to assess the association between cTnI and BNP levels and 28-day mortality, and their prognostic accuracy.

Results: A total of 333 septic patients were included in this study (mean age [SD], 64.7 [15.2] years; 65.8 % male), of whom 63 (18.9 %) patients died during 28 days. Elevated peak cTnI levels, identified in 233 patients (70.0 %), were independently associated with higher 28-day mortality in septic patients, even after adjusting for SOFA scores, BNP, and other confounding variables. (adjusted HR 2.33, 95 % CI 1.08-5.04, P = 0.03). However, neither first-day cTnI nor BNP levels remained independent predictors of 28-day mortality. Sensitivity analyses for the magnitude of cTnI elevation as a predictive variable also yielded similar results. Compared to first-day cTnI, first-day BNP, and peak BNP, the peak cTnI had the most significant and modest area under the ROC curve (AUC: 0.64 [0.57-0.71]).

Conclusions: Elevated peak cTnI or the magnitude of cTnI, rather than first-day, could independently predict the risk of 28-day mortality in septic patients. This finding highlighted the importance of dynamic monitoring cTnI levels for risk stratification identification and management in septic patients.