Biological signatures of structural brain injury: Inflammatory and coagulation parameters and their association with computed tomographic severity in traumatic brain injury

Objective: To evaluate the relationship between systemic inflammatory-coagulopathic derangements and radiological severity of injury among patients admitted with traumatic brain injury (TBI). Methodology: This retrospective analytical cohort study was conducted at the Department of Neurosurgery, Unit-I, Punjab Institute of Neurosciences, Lahore, Pakistan. Medical records of consecutive adult patients admitted with acute traumatic brain injury from January 2026 to May 2026 were reviewed. Data regarding patient demographics, clinical features, radiological variables were collected. Statistical analysis was performed using SPSS Version 26. Principal Component Analysis with varimax rotation was employed to derive the composite biological index. Independent associations between the biological index and radiological severity was explored using multivariable ordinal logistic regression. Results: Of the total 94 patients included in the study, there were 78.7% (74) males, and the mean age was 40.2±22.2 years. Prothrombin time (PT), activated partial thromboplastin time (aPTT) and International normalized ratio (INR) had high factor loadings for first component i.e., 0.866, 0.795 and 0.934 respectively and was labelled as coagulation factor while Neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) for second component i.e., 0.956 and 0.960 respectively and was labelled as inflammation factor. Higher coagulation factor scores were found to be independently associated with radiological severity in TBI when graded according to Marshall classification after adjustment for age, gender and GCS at admission (β= 0.615, adjusted OR:1.85, 95% CI: 1.13-3.03, p = 0.014) and borderline association for Rotterdam CT score i.e., (β= 0.375, adjusted OR: 1.46, 95% CI: 0.98-2.16, p = 0.063). No independent correlation was observed between inflammation score and radiological severity in TBI (p>0.05). Conclusion: Composite Coagulation factor score may serve as independent predictor of severity of structural brain injury on CT proposing it as a biologically relevant exploratory marker of structural brain injury in TBI.