(A) Association between CSF and serum neurofilament light (NfL) obtained
from players with postconcussion symptoms (PCS) due to repetitive mild
concussion (n = 28) and healthy controls (n = 14). (B) Serum
NfL concentrations in players who contributed blood samples during
preseason, players with acute concussion (AC), and players with PCS. (C)
Serum concentrations in relation to return to play (RTP) and duration of
PCS. (D) Individual areas under the receiver operating characteristics
curve (AUROCs) (error bars indicate the mean and 95% confidence
interval) for how well serum NfL distinguishes players with AC from
preseason controls, those with RTP ≥10 days from those with RTP
<10 days, those with PCS >1 year from those with PCS ≤1
year, and players with PCS >1 year from preseason controls. (E)
Higher concentration of CSF or serum NfL is associated with the number
of concussions. (F) NfL increases with symptom severity score. Preseason
samples are from professional hockey players who contributed samples
during the preseason. The p values are from
Kruskal-Wallis test, adjusted for multiple comparisons with the
Benjamini-Hochberg procedure. Fitted lines are from the linear
regression model (overlaid for visual clarity). The y-axes of plots E
and F are normalized for comparison between CSF and serum values. RPQ
= Rivermead Post-Concussion Questionnaire.