Effect of blood alcohol on the diagnostic accuracy of glial fibrillary acidic protein and ubiquitin carboxy-terminal hydrolase L1 for traumatic intracranial hemorrhage: A TRACK-TBI study.

Summary

In this prospective multicenter TRACK-TBI diagnostic study, investigators examined whether alcohol intoxication changed the accuracy of GFAP plus UCH-L1 for CT-detectable traumatic intracranial injury. Among 2,320 patients assessed within 24 hours of TBI at 18 US Level I trauma centers, combined biomarker AUC was 0.949 with blood alcohol >300 mg/dL, 0.858 with 81–300 mg/dL, 0.849 with 0–80 mg/dL, and 0.883 when alcohol level was unavailable. The study supports preserved discrimination in intoxicated patients but does not itself validate a disposition pathway.

Why it matters

Intoxication alone need not make GFAP/UCH-L1 biologically uninterpretable in an otherwise eligible TBI evaluation. Use remains bounded by the assay's validated indication and local implementation, not by this observational subgroup analysis alone.

Main findings

• 48.3% of the cohort had a positive brain CT.
• Combined biomarker AUC was 0.949 with blood alcohol >300 mg/dL versus 0.849 with 0–80 mg/dL.
• Elevated alcohol did not lower combined-biomarker discrimination in this cohort.

Limitations

This was a secondary diagnostic-accuracy analysis with a high CT-positive prevalence (48.3%) at Level I trauma centers. It did not test a biomarker-led CT-reduction or discharge strategy, and the most severe alcohol subgroup was small (n=54).