Prevalence and Risk Factors for Clinically Significant Brain Injury among Patients with Mild Traumatic Brain Injury in Abuja, Nigeria

Background: Mild traumatic brain injury (mTBI) is common, yet a clinically important subset of patients with a Glasgow Coma Scale (GCS) score of 13–15 have intracranial lesions that require admission, close observation, or neurosurgical follow-up. Clinical decision rules exist to guide CT use, but their applicability in settings with constrained CT access and a high prevalence of high-energy mechanisms like road traffic crashes is uncertain. Objective: To determine the prevalence and describe risk factors of clinically significant brain injury on CT among patients with mTBI presenting to a Nigerian trauma centre. Methods: We conducted a prospective observational study of 103 consecutive patients aged ≥16 years with mTBI (GCS 13–15) presenting to the National Trauma Centre, National Hospital Abuja (November 2021–July 2022). Demographics, injury mechanism, and clinical features (including loss of consciousness [LOC], post-traumatic amnesia, polytrauma, and GCS) were recorded using a structured proforma. The primary outcome was clinically significant brain injury on non-contrast head CT, defined as any acute intracranial finding warranting admission with neurosurgical follow-up or close neurological observation. Results: Clinically significant brain injury was present in 45/103 patients (43.7%). Importantly, 88.9% of clinically significant injuries occurred in patients presenting with a GCS of 14 or 15. Key risk factors included male sex, involvement in road traffic crashes (particularly as a pedestrian), and the presence of loss of consciousness. Conclusion: In similar resource-constrained environments, these features should be used to identify high-risk patients, prompting a low threshold for CT imaging and neurosurgical evaluation.