Table 4.

Group comparisons of biomarker concentrations between patients with mTBI without somatic injuries (mTBI–) and community controls, at acute, 3 and 12 months, calculated using contrast analyses based on the linear mixed model results.

	Acute	3 months	12 months
	Estimate‡ (95% CI) p-value	Estimate‡ (95% CI) p-value	Estimate‡ (95% CI) p-value
	Mean % elevation	Mean % elevation	Mean % elevation
GFAP	0.73 (0.63 to 0.83), p < 0.0001	0.01 (−0.07 to 0.09), p = 0.257	−0.001 (−0.08 to 0.08), p = 0.980
	47.6%	1.0%	0.8%
NFL	0.03 (−0.06 to 0.11), p = 0.518	0.14 (0.07 to 0.21), p = 0.0001	0.01 (−0.07 to 0.08), p = 0.889
	6.8%	19.8%	1.5%
Tau	0.14 (0.05 to 0.23) p = 0.002	−0.03 (−0.10 to 0.04) p = 0.374	−0.06 (−0.13 to 0.02) p = 0.137
	41.6%	−6.3%	−12.3%

^‡Estimate refers to mean group differences as estimated by the mixed model; 95% CI is the 95% confidence interval of the estimated group difference. All values are log transformed. Mean % elevation is the percentage elevation in the mean log-transformed biomarker values of patients with mTBI compared to controls. Significant differences are bolded. Bonferroni-adjusted alpha level = 0.017.

mTBI, mild traumatic brain injury; GFAP, Glial fibrillary acidic protein; NFL, Neurofilament light.