Neurology. 2025 Mar 11;104(5):e210308. doi: 10.1212/WNL.0000000000210308. Epub 2025 Feb 7.
ABSTRACT
BACKGROUND AND OBJECTIVES: Previous studies on sport-related concussion (SRC) may have measured brain injury blood-based biomarker, glial fibrillary acidic protein (GFAP), either before or after its peak, potentially underestimating the diagnostic value. The primary aim of this study was to evaluate the diagnostic performance of serum GFAP at 24 hours post-SRC. Secondary objectives included assessing whether the timing of sample collection relative to an Australian football match (with or without SRC) affected GFAP levels, evaluating if combining GFAP with symptoms improved discrimination of SRC compared with symptoms alone, and determining the diagnostic utility of serum neurofilament light (NfL) levels at 24 hours post-SRC.
METHODS: In a prospective cohort study, adult male and female Australian football players of the Victorian Amateur Football Association (Melbourne, Australia) with and without SRC had blood sampled around 24 hours postinjury/postmatch. GFAP and NfL levels were quantified using Simoa assays, and area under the curve (AUC) values were calculated for time bins of 16-24 hours, 24-32 hours, and 36-52 hours. Symptom severity at blood collection was assessed using the Sport Concussion Assessment Tool 5 (SCAT).
RESULTS: A total of 151 athletes with SRC (median age 22.5 years; 85% male) and 97 controls (median age 24.3 years; 86% male) were sampled at a median of 24.5 hours (interquartile range [IQR] 21.7-28.0; min-max 16-51.5). Time to sample postmatch did not affect GFAP levels in controls; however, higher GFAP levels correlated with shorter time post-SRC (Spearman r = -0.25, 95% CI -0.40 to -0.09). Median GFAP concentrations were 65.9 pg/mL (IQR 49.1-81.3) in controls, and for SRC, 124.6 pg/mL (IQR 86.7-190.7) at 16-24 hours, 94.5 pg/mL (IQR 61.6-163.9) at 24-32 hours, and 59.9 pg/mL (IQR 49.1-94.7) at 36-52 hours. AUC values at 16-24 and 24-32 hours were 0.83 (95% CI 0.76-0.90) and 0.72 (95% CI 0.64-0.80), respectively. Furthermore, combining GFAP with SCAT symptoms at 16-24 hours enhanced discriminatory capability compared with SCAT symptoms alone (AUC increased from 0.91 to 0.97; z = 2.48, p = 0.01). Serum NfL had a limited diagnostic value (AUC ≤0.60).
DISCUSSION: Serum GFAP measured at 16-24 hours following potential or suspected SRC may be a useful objective aid to SRC diagnosis.
PMID:39919259 | DOI:10.1212/WNL.0000000000210308
