The Impact of Antithrombotic Agents on In-Patient and Post-Discharge Mortality after Trauma Brain Injury
April DeStefano1, Satya Vedula1, Joshua Stodghill 1, Jacob Gillen 1, Michael Nussbaum1, Katie Bower1, Tonja Locklear2, Bryan Collier1
1Virginia Tech Carilion School of Medicine, 2Carilion Clinic
Objective:
Determine the impact AA have on IPM and PDM TBI patients
Background:
Antithrombotic agents (AA) protect against thrombotic events with high risk of bleeding. It is unclear whether risks associated with TBI should impact decisions to start AA in the elderly, a group with the highest incidence of head injury. We hypothesize AA increase inpatient mortality (IPM) and 1y post-discharge mortality (PDM) rates in elderly TBI patients.
Design/Methods:
Elderly (age >65) and adult (age 18-64) TBI patients were identified in a level I Trauma registry 2008-2017.Patients were sorted by AA exposure (+AA and –AA). The Trauma registry was merged with the National Death Index. Mortality was evaluated by chi-square, Fisher’s exact, and Wilcoxon rank-sum tests. Logistic regression determined the effect of AA on IPM and PDM.
Results:
Of 1,265 patients, 625 were using antithrombotic agents at the time of injury (+AA) and 640 were not (–AA). There were 537 adults and 687 elderly patients. AA was associated with older age, presence of a comorbidity (p-value ≤0.0001), and higher Glascow Coma Score on arrival (+AA Median=15 and -AA Median=14, p-value ≤0.0001). There was no difference in AIS head (+AA=4, -AA=4 p-value 0.12), or IPM (+AA=14.9%, -AA=16.4% p-value <0.4551). The +AA had higher PDM (+AA=36.0%, -AA=24.7%, p-value ≤ 0.0001) and was older at death (+AA Median=84 and -AA Median=64, p-value ≤0.0001). To control for age, the data were grouped into adult and elderly populations. Logistic regression showed AA had no impact on elderly IPM (AUC=0.8890), PDM (Odds Ratio=0.970, p-value <0.8937, AUC=0.7230), or adult IPM (AUC=0.9405). AA- adults had decreased PDM (OR= 0.155, p-value=0.0008, AUC=0.7716).
Conclusions:
Antithrombotic therapy is a confounder for age and co-morbidities, and not associated with IPM or PDM. These data should be considered when discussing risks and benefits of AA in the elderly. Functional outcomes may be more pertinent and require future study.