Ischemia-modified Albumin as a Biomarker for Prediction of Poor Outcome in Patients With Traumatic Brain Injury: An Observational Cohort Study.

Background: Biomarkers can assist in outcome prediction and therapeutic decision making after traumatic brain injury (TBI). The aim of this study was to evaluate the role of ischemia-modified albumin (IMA) in the prediction of mortality in patients with TBI.

Methods: In this observational study IMA was measured on admission to intensive care unit (D0) and 24 hours later (D1) in a cohort of patients with mixed TBI severity. The primary outcome was the correlation between IMA and 28-day mortality. Secondary outcomes included the incidence of elevated IMA, and the correlation between the severity of TBI and IMA, and between IMA and change in Glasgow coma score (GCS). The area under receiver operating characteristic curve analysis was performed to detect optimal IMA cut-off value for the detection of mortality.

Results: Fifty-four patients were included in the study; IMA was elevated in 49 (90.7%) on admission to the intensive care unit. Of the 49 patients with elevated IMA, 22 had a decrease in IMA while 27 had an increase by 24 hours. IMA levels were higher at D0 and D1 (P<0.001 for both) in patients who died compared with those who survived. Twenty-one patients died (mortality rate 38.9%); all had elevated IMA on D0 and D1 and higher IMA levels at D1 compared with D0. Optimal cut-off values for IMA predicted mortality with 76.2% sensitivity and 81.8% specificity at D0 and with 100% sensitivity and specificity at D1. IMA values at D0 and D1 were correlated with D0 and D1 GCS, respectively (both P<0.001).

Conclusion: IMA levels were elevated in patients following TBI, and can predict mortality with high sensitivity and specificity.