Distribution of contemporary sensitivity troponin in the emergency department and relationship to 30-day mortality: The CHARIOT-ED substudy

BACKGROUND: Contemporary sensitivity troponin (cs-cTn) concentrations above the upper limit of normal (ULN) are seen in a wide range of clinical conditions and evidence is growing that suggests cs-cTn may be a biomarker of future morbidity and mortality. OBJECTIVES: Our aim was to test the hypothesis that cs-cTn, measured in the emergency department, may be a biomarker for 30-day mortality, irrespective of the patient's presentation. METHOD: In all 5,708 consecutive cases, contemporary sensitivity troponin I (cs-cTnI) was measured either as requested by the clinical team or as part of the study, in which case both the clinical team and the patient were unaware of the result. Basic demographics were available from the original study and 30-day mortality was derived from NHS Digital data. RESULTS: In patients whose cs-cTnI test was requested solely as part of the study, 30-day mortality increased with increasing cs-cTnI concentrations (0% with undetectable concentrations to 14.7% with concentrations above the ULN). Multivariable Cox regression analysis showed that log(10)cs-cTnI concentration was independently associated with 30-day mortality. CONCLUSION: Increasing cs-cTnI concentrations are associated with higher short-term mortality as well as length of stay. As such, cs-cTnI measurements may provide useful prognostic information.