The role of cardiac troponin I in prognostication of patients with isolated severe traumatic brain injury. Issue 3 (March 2016) - Cai, Stephen S.
Abstract : BACKGROUND: Cardiac dysfunction is frequently observed after severe traumatic brain injury (sTBI); however, its significance is poorly understood. Our study sought to elucidate the association of cardiac troponin I (cTnI) elevation with all-cause in-hospital mortality following isolated sTBI (brain Abbreviated Injury Scale score ≥3 and admission Glasgow Coma Scale score ⩽8, no Abbreviated Injury Scale score ≥3 to any other bodily regions). METHODS: We retrospectively reviewed all adult patients (aged ≥18 years) with isolated sTBI admitted to a Level I trauma center between June 2007 and January 2014. Patients must have cTnI values within 24 hours of admission. Mortality risks were examined by Cox proportional hazard model. RESULTS: Of 580 patients identified, 30.9% had detectable cTnI in 24 hours of admission. The median survival time was 4.19 days (interquartile range, 1.27–11.69). When adjusted for potential confounders, patients in the highest cTnI category (≥0.21 ng/mL) had a significantly higher risk of in-hospital mortality (hazard ratio, 1.39; 95% confidence interval, 1.04–1.88) compared with patients with undetectable cTnI. Mortality risk increased with higher troponin levels ( p < 0.0001). This association was more pronounced in patients aged 65 years or younger (hazard ratio, 2.28; 95% confidence interval, 1.53–3.40; p < 0.0001) while, interestingly, insignificant in those older than 65 years ( p = 0.0826). CONCLUSION: Among patients with sTBI, cTnI elevation is associated with all-cause in-hospital mortality via a nonlinear positive trend. Age modified the effect of cTnI on mortality. LEVEL OF EVIDENCE: Prognostic and epidemiologic study, level III. Abstract : Supplemental digital content is available in the text.