Blood Biomarkers for Return to Play after Concussion in Professional Rugby Players

S100B, Actor and Biomarker of Mild Traumatic Brain Injury

“…This is particularly important as the implementation of a blood biomarker in the SRC screening process may enhance the diagnostic performances and improve the overall management of concussed players. When screening for SRCs, we recommend interpreting S100B levels through a personalized medical approach, by determining for each player a baseline measured away from any sport practice [ 112 ]. This approach reduces the influence of inter-individual variability subsequent to concussion history [ 112 ].…”

“…When screening for SRCs, we recommend interpreting S100B levels through a personalized medical approach, by determining for each player a baseline measured away from any sport practice [ 112 ]. This approach reduces the influence of inter-individual variability subsequent to concussion history [ 112 ]. We also recommend assessing the intra-individual variability to establish the effect of contact sport on the player’s baseline over a season.…”

“…We also recommend assessing the intra-individual variability to establish the effect of contact sport on the player’s baseline over a season. In these conditions, we have recently demonstrated the interest of incorporating S100B measurement to the Head Injury Assessment (HIA) protocol in the management of concussed professional rugby players [ 112 ]. The HIA protocol combines cognitive, balance, and memory evaluation, and consists of three assessments: immediately post-injury (HIA-1), within 3 h of the injury (HIA-2), and a follow-up at 36–48 h post-injury (HIA-3) [ 113 ].…”

“…A concussion will be considered unresolved if the HIA-3 examination is still positive [ 113 ]. In our study, an individual increase in S100B blood concentration (related to baseline) measured at 36 h post-match was predictive of non-resolutive concussion [ 112 ]. To conclude, the introduction of personalized measurement of serum S100B in the HIA-3 clinical assessment may help in a more objective identification of non-resolutive concussions, allowing a better protection for the players, in line with the recommendations of the 2016 Berlin meeting [ 17 ].…”

“…Physiologically, sRAGE is hypothesized to counteract the detrimental action of RAGE as a competitive inhibitor of the signaling pathway and as a ligand scavenger [ 126 , 130 ]. Recently, we hypothesized that concussion resolution at 36 h in professional rugby players may be related to an elevation in sRAGE, which may regulate blood levels of S100B and thus preserve brain function [ 112 ]. Furthermore, the S100B/RAGE pathway is also involved in chronic traumatic encephalopathy (CTE), a complication that affects some athletes participating in contact sports and exposed to repetitive head impacts [ 131 ].…”