Association of Acute Blood Biomarkers with Diffusion Tensor Imaging and Outcome after Mild Traumatic Brain Injury

Abstract

Association of blood levels of the axonal biomarker neurofilament light and brain white matter (WM) injury in mild traumatic injury (mTBI) has been reported. We studied 92 patients with mTBI having plasma samples for glial fibrillary acidic protein (GFAP), interleukin 10 (IL-10), heart fatty-acid binding protein (H-FABP), S100 calcium-binding protein B (S100B), total tau (T-tau), and amyloid beta 40 and 42 (Aβ40 and Aβ42) within 24 h of admission and diffusion tensor imaging available ≥ 90 days post-injury. Patients were divided into subgroups based on acute head computed tomography (CT-positive and CT-negative). Outcome was assessed using Glasgow Outcome Scale-Extended (GOSE) at the follow-up visit and dichotomized as complete (GOSE 8) and incomplete recovery (GOSE <8). Mean fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) were calculated from the skeletonized WM tracts of the whole brain. GFAP and T-tau had negative correlations with FA and positive correlations with MD and RD in the whole mTBI cohort in the CT-positive subgroup, and in the incomplete recovery group. IL-10 had a negative correlation with FA in the whole mTBI cohort and in the incomplete recovery group. IL-10 had a positive correlation with MD and RD only in the incomplete recovery group. CT-positive patients had significantly lower FA levels and higher levels of MD and RD than the CT-negative patients. Admission plasma levels of GFAP, IL-10, and T-tau correlated with WM integrity measured ≥ 90 days post-injury. Higher acute levels of these biomarkers may be associated with axonal injury.