Prevalence and Predictors of Inappropriate Antithrombotic Prescription in Patients Presenting With Traumatic Brain Injury

Background and objectives: A growing proportion of the US population is on antithrombotic therapy (AT), most significantly within the older subpopulation. Decision to use AT is a balance between the intended benefits and known bleeding risk, especially after traumatic brain injury (TBI). Preinjury inappropriate AT offers no benefit for the patient and also increases the risk of intracranial hemorrhage and worse outcome in the setting of TBI. Our objective was to examine the prevalence and predictors of inappropriate AT among patients presenting with TBI to a Level-1 Trauma Center.

Methods: A retrospective chart review was performed on all patients with TBI and preinjury AT who presented to our institution between January 2016 and September 2020. Demographic and clinical data were collected. Appropriateness of AT was determined through established clinical guidelines. Clinical predictors were determined by logistic regression.

Results: Of 141 included patients, 41.8% were female (n = 59) and the average age (mean ± SD) was 80.6 ± 9.9. The prescribed antithrombotic agents included aspirin (25.5%, n = 36), clopidogrel (22.7%, n = 32), warfarin (46.8%, n = 66), dabigatran (2.1%, n = 3), rivaroxaban (Janssen) (10.6%, n = 15), and apixaban (Bristol-Myers Squibb Co.) (18.4%, n = 26). The indications for AT were atrial fibrillation (66.7%, n = 94), venous thromboembolism (13.4%, n = 19), cardiac stent (8.5%, n = 12), and myocardial infarction/residual coronary disease (11.3%, n = 16). Inappropriate antithrombotic therapy use varied significantly by antithrombotic indication ( P < .001) with the highest rates seen with venous thromboembolism. Predictive factors also include age ( P = .005) with higher rates younger than 65 years and older than 85 years and female sex ( P = .049). Race and antithrombotic agent were not significant predictors.

Conclusion: Overall, 1 in 10 patients presenting with TBI were found to be on inappropriate AT. Our study is the first to describe this problem and warrants investigation into possible workflow interventions to prevent post-TBI continuation of inappropriate AT.