Serum Glial Fibrillary Acidic Protein and S100B Profiles in Severity and Outcome Assessment of Moderate and Severe Head Injury Patients in India

Abstract Background: Traumatic brain injury (TBI) is a significant global health issue, with India witnessing approximately 150,000 deaths and 50,000 TBI-related fatalities annually. Severity is classified as mild, moderate, or severe using the Glasgow Coma Scale (GCS). Imaging and blood biomarkers such as serum glial fibrillary acidic protein (GFAP) and S100B aid in diagnosis and outcome prediction, yet imaging facilities are scarce in India. This highlights the necessity for dependable biomarkers. GFAP indicates astroglial injury, while S100B suggests neuronal injury, both in TBI patients’ blood. However, their associations and utility in the Indian population require further exploration. Our study addresses this gap by examining serum GFAP and S100B levels in moderate and severe TBI patients, correlating them with radiological findings and clinical outcomes. Methodology: This prospective observational study was conducted in a tertiary care hospital on 212 patients (106 each for moderate and severely injured groups). Initial disease severity was assessed by GCS score. Outcome assessments were required of surgical intervention and mortality within 5 days. Results: S100B superseded GFAP in assessing disease severity. Receiver operating characteristic analysis showed that S100B was successful with 66% sensitivity and specificity for a cutoff value of 78.77 pg/ml. For early mortality prediction, sensitivity (S100B = 81%–87%, GFAP = 64.1%–78.6%), specificity (S100B = 60.2%–99.2%, GFAP = 54.5%–74.6%), and area under the curve-wise (S100B = 0.721–0.909, GFAP = 0.614–0.763) S100B model performed better than the GFAP model for all corresponding cutoffs (ranged S100B = 86.53–118.56 pg/ml, GFAP = 30.87–34.5 ng/ml). Conclusion: Taken together, our study provides strong evidence that S100B is a better marker of severity and outcome assessment than GFAP.