Clinical bottom line
Blood-based biomarkers hold promise as adjunctive tools to inform prognosis and tailor rehabilitation intensity in traumatic brain injury (TBI). Emerging evidence suggests that specific biomarkers reflecting neuronal injury, inflammation, and repair processes may correlate with injury severity and functional outcomes. However, current data remain preliminary and heterogeneous, limiting routine clinical application. Clinicians should consider biomarker results in the context of comprehensive clinical and imaging assessments while awaiting further validation from prospective studies.
What the evidence shows
Recent reviews and expert analyses highlight several blood-based biomarkers under investigation for TBI prognosis and rehabilitation guidance. Key candidates include glial fibrillary acidic protein (GFAP), ubiquitin carboxy-terminal hydrolase L1 (UCH-L1), neurofilament light chain (NfL), and inflammatory cytokines (Rezzag Lebza et al., 2023; Alvacite et al., 2026). These biomarkers reflect distinct pathophysiological processes such as astroglial injury, neuronal damage, axonal degeneration, and systemic inflammation.
Studies demonstrate that elevated acute-phase levels of GFAP and UCH-L1 correlate with injury severity and poorer neurological outcomes (Rezzag Lebza et al., 2023). NfL, a marker of axonal injury, shows promise in predicting long-term functional impairment and cognitive deficits (Alvacite et al., 2026). Inflammatory markers may provide insight into secondary injury cascades that influence recovery trajectories (Rezzag Lebza et al., 2023).
Prognostic models incorporating biomarker panels alongside clinical variables have shown improved accuracy in outcome prediction compared to clinical assessment alone (Fusco et al., 2015; Kothari et al., 2012). This suggests potential utility in stratifying patients for rehabilitation intensity and monitoring response to therapy. However, heterogeneity in study populations, timing of sampling, and assay methods complicate direct comparisons and clinical translation.
Caveats and uncertainty
Despite encouraging findings, the evidence base remains limited by small sample sizes, variable biomarker panels, and lack of standardized protocols (Rezzag Lebza et al., 2023). Most studies are observational or retrospective, with few prospective trials validating biomarker-guided rehabilitation strategies. The temporal dynamics of biomarker release and clearance are incompletely understood, raising questions about optimal timing for prognostication.
Additionally, confounding factors such as extracranial injuries, comorbidities, and preexisting neurological conditions may influence biomarker levels and reduce specificity (Alvacite et al., 2026). The clinical significance of biomarker fluctuations during subacute and chronic phases of TBI recovery is also unclear.
Current assays require further standardization and regulatory approval before widespread clinical use. Cost-effectiveness and accessibility in diverse healthcare settings remain to be established. Therefore, blood-based biomarkers should not replace comprehensive clinical evaluation but may serve as complementary tools pending further validation.
How this may change practice
If validated in prospective clinical trials, blood-based biomarkers could enhance personalized rehabilitation planning by providing objective measures of injury severity and recovery potential. This may enable clinicians to tailor rehabilitation intensity, monitor treatment response, and identify patients at risk for poor outcomes earlier in the care continuum (Alvacite et al., 2026).
Integration of biomarker data with clinical and imaging findings could improve prognostic accuracy, facilitating shared decision-making and resource allocation. Biomarker-guided rehabilitation protocols might optimize functional gains while minimizing over- or under-treatment.
In the near term, clinicians should remain informed about evolving biomarker research and consider participation in clinical studies. Multidisciplinary collaboration between rehabilitation specialists, neurologists, and laboratory scientists will be critical to translate biomarker discoveries into practical clinical tools.