Table 1.

Longitudinal Serum SNTF, Tau, and S100β Concentrations in Relation to PCS Severity

Time postconcussion	<6 days RTP	>6 days RTP	p value
SNTF, 1 h	20.4±3.1 (n=8)	35.5±12.9 (n=16)	>0.5
12 h	19.0±2.4 (n=8)	50.4±19.0 (n=14)	0.087
36 h	19.3±3.0 (n=6)	41.0±8.4 (n=14)	0.014
12/36 h mean	18.6±2.1 (n=8)	45.8±11.6 (n=17)	0.004
6 days	17.0±4.0 (n=5)	44.6±15.4 (n=13)	0.15
Tau, 1 h	9.0±2.1 (n=8)	23.1±7.0 (n=17)	0.070
12 h	4.8±1.8 (n=8)	17.9±7.4 (n=15)	0.039
36 h	5.7±1.6 (n=7)	28.0±12.5 (n=14)	0.11
6 days	8.0±1.7 (n=5)	35.6±14.5 (n=12)	0.34
S100β, 1 h	106±21 (n=8)	72.7±5.6 (n=17)	0.27
SNTF12/36+Tau12	69±8 (n=8)	224±65 (n=17)	0.011

The serum concentrations of the three markers (mean units±standard error of the mean) are presented in relation to the severity of PCS, dichotomized on the basis of a delay in RTP of <6 days or ≥6 days. SNTF and tau serum concentrations were higher in the players with more persistent PCS, whereas S100β serum levels were not. The increase in serum SNTF was statistically significant by Mann-Whitney's U test at 36 h and for the 12- to 36-h mean, whereas the elevation in serum tau was statistically significant at 12 h postconcussion. The multi-variate measure of serum SNTF (mean at 12–36 h) and tau (at 12 h) was also significantly different based on the persistence of PCS, but at no combination of time points were multi-variate analyses of SNTF and tau related more strongly to PCS severity than the mean SNTF levels at 12–36 h alone. The bolded p values are statistically significant.

SNTF, calpain-derived αII-spectrin N-terminal fragment; PCS, postconcussion symptom; RTP, return to play.