Comprehensive Summary
Traumatic Brain Injury (TBI) remains a leading cause of death and long-term disability worldwide. This study investigates whether serum interleukin-6 (IL-6) measured post-TBI could serve as a prognostic biomarker of long-term (6-month) outcomes. Eighty-eight adults ( >17 years) with moderate to severe TBI admitted to a Colombian Neurological ICU had IL-6 measured within 24 hours (Day 0), and again on days 3 and 7. Researchers calculated 6-month outcomes using the GOSE and analyzed IL-6’s predictive value with multivariable logistic regression. Higher day-0 IL-6 was associated with increased risk of 6-month mortality and disability. Day-0 IL-6 independently predicted an unfavorable outcome (adjusted OR 1.15, 95% CI 1.1-1.2; p=0.031). A model combining IL-6, age, and Glasgow Coma Scale (GCS) score achieved an AUC of 0.89. An optimal cutoff of 59 pg/mL yielded ~78% sensitivity and ~81% specificity. Decision curve analysis (DCA) suggested that incorporating IL-6 into prognostic models provided clinical benefit. However, calibration concerns arose when IL-6 was integrated with the IMPACT model. Overall, the findings support IL-6 as a promising early prognostic biomarker in TBI.
Outcomes and Implications
TBI is a major health challenge, and current prognostic mechanisms usually fail to capture the biological variety of injuries. Measuring IL-6 early could help clinicians triage patients, guide treatment intensity, and provide families with clearer expectations in the near future. Early detection may support clinical decision making, inform expectations of patients and their families, and create precise medical trials. On the contrary, this study is limited to a single center, a modest sample size, and requires external validation. These limitations do not account for multiple factors, such as generalizability to broader populations, comorbidities, and confirmation of appropriate application.