Relationship Between Time of Hospital Arrival and Clinical and Fluid Biomarker Outcomes in Traumatic Brain Injury
Aaron Anandarajah1, Alexa Walter2, James Gugger2, Cillian Lynch2, Andrea Schneider2, Danielle Sandsmark2, Ramon Diaz-Arrastia2
1Neurology, University of Pennsylvania, 2University of Pennsylvania
Objective:
Identify variables related to delayed emergency department (ED) presentation after traumatic brain injury (TBI).
Background:
Delayed presentation to ED after TBI may differ based on demographic and clinical variables and may confound interpretation of clinical assessments and blood biomarker testing.
Design/Methods:
Patients with non-penetrating TBI were enrolled after admission to an urban trauma center. Time between injury and ED arrival was categorized as <1 hour, 1-6 hours, and >6 hours. Blood was drawn on Day 1, Day 3, 2 weeks, and 6 months post-injury and analyzed using Simoa HD-X Neuro4plex assay for NfL, GFAP, and UCH-L1 levels. Demographic variables and clinical outcomes by arrival time category were assessed with Chi-Square or Kruskal-Wallis tests. For fluid blood-biomarkers, log2 levels were compared between arrival time categories using one-way ANOVA.
Results:
187 individuals with TBI (mean age 47.7 years, 71% male, 50% white, and median Glasgow Coma Score (GCS) of 15) were included in this analysis. 60% arrived in <1 hour, 24% 1-6 hours, and 11% >6 hours (only 3% presented >24 hours after injury). There were significant differences by arrival time categories by injury mechanism, with 84% motor vehicle incidents presenting within an hour (χ2=27.6, p<0.001). Additionally, younger patients (H=13.6, p=0.001), and Black individuals (χ2=17.2, p=0.002), also were most likely to arrive within an hour. There were no differences in arrival time category by sex, head CT findings, or GCS. For blood-biomarkers, there were no differences between arrival time categories for NfL, UCH-L1, and GFAP.
Conclusions:
Mechanism of injury, age, and race are identifiable factors that may influence both arrival time at ED and clinical outcomes and interpretation of biomarker results after TBI. Since our cohort mostly presented within 12 hours, and CT and biomarker results were not influenced, future research should focus on a small cohort of patients with ED presentation beyond 12 hours.