Early hematoma expansion provides incremental prognostic information beyond admission characteristics for 6-month functional outcome after adult traumatic brain injury

Background Early hematoma expansion (HE) reflects interval progression of traumatic intracranial hemorrhage, but its association with long-term outcome and its prognostic contribution beyond admission characteristics remain incompletely defined. We evaluated whether HE was independently associated with 6-month functional outcome and provided incremental prognostic information beyond admission characteristics. Methods This single-center retrospective study included 640 adults with traumatic brain injury, including 285 with HE. HE was determined from the first two in-hospital head computed tomography scans obtained within 48 h after injury and was defined as a new intracranial hemorrhagic lesion or an increase of >3 ml in total hemorrhage volume. Six-month outcome was assessed using the Glasgow Outcome Scale (1–3 unfavorable; 4–5 favorable). HE was added to a study-specific baseline model comprising age, admission Glasgow Coma Scale score, D-dimer, baseline hematoma volume, cerebral contusion, diffuse axonal injury, frontal lobe involvement, and long-bone fracture. Results At 6 months, 145 patients (22.7%) had an unfavorable outcome. HE was independently associated with a lower likelihood of favorable outcome (OR, 0.20; 95% CI, 0.10–0.42). Adding HE reduced the Akaike information criterion from 392.767 to 365.908 (likelihood-ratio P < 0.001) and increased the area under the curve from 0.920 to 0.929 (ΔAUC = 0.009; DeLong P = 0.0289). Prognostic heterogeneity remained among HE-positive patients. Conclusions Early HE is independently associated with 6-month functional outcome in adult patients with TBI. As a readily obtainable finding on routine serial CT, HE may help refine early prognostic assessment in patients with TBI.