Forrest, M J

Problem Statement: The prognostic value of troponin elevation in septic ICU patients without known history of cardiac disease remains unclear, particularly after accounting for overall illness severity. Background: Minor troponin rises are frequent during sepsis, yet clinicians still lack a clear cut-point that signals danger once cardiac disease is ruled out. We asked whether a modest increase in troponin-T predicts in-hospital death beyond global illness severity. Methods: We studied 1 221 adult first ICU stays labelled “sepsis” in the eICU Collaborative Research Database and removed any case with a cardiac admission diagnosis. Implausible or missing laboratory values were imputed by multiple imputation. Hospital mortality was modelled with logistic regression that included troponin (a continuous and a binary model with threshold > 0.04 ng/mL) together with age, sex, lactate, albumin, BUN, creatinine, intubation status, vasopressor use, dialysis requirement and APACHE-IV predicted mortality. A natural-spline model explored non-linear behavior. Findings were checked in a 1:1 propensity-matched cohort. Results: Overall mortality was 11.7%. Troponin exceeded 0.04 ng/mL in 38% of patients. After adjustment for APACHE-IV probability and other covariates, a troponin level > 0.04 ng/mL was associated with almost twice the odds of death (OR ≈ 1.9), whereas the continuous model suggested only a modest trend (OR ≈ 1.1 per ng/mL). The spline curve rose steeply between 0 and 0.10 ng/mL and flattened thereafter, pinpointing an inflection near 0.05 ng/mL. Matching on all measured confounders confirmed that high-troponin patients had about three-fold greater mortality (OR ≈ 2.8, 1.55-5.05; p<0.001), highlighting that even modest troponin elevation is an independent risk marker for death in septic ICU patients. A bedside heat-map combining troponin, albumin and need for intubation illustrated a simple gradient: risk climbs from 2 % in low-troponin, well-albuminised, non-intubated patients to nearly 7 % when troponin exceeds 0.10 ng/mL in intubated, hypo-albuminemic patients. Conclusions: Even modest troponin elevations (> 0.04 ng/mL) independently predict mortality in sepsis after rigorous adjustment and matching on APACHE-IV physiology, lactate, and organ-support variables. This biologic threshold supports incorporating troponin into bedside triage and future septic cardiomyopathy trials.