Subject-Specific Increases in Serum S-100B Distinguish Sports-Related Concussion from Sports-Related Exertion

Abstract

BackgroundThe on-field diagnosis of sports-related concussion (SRC) is complicated by the lack of an accurate and objective marker of brain injury.PurposeTo compare subject-specific changes in the astroglial protein, S100B, before and after SRC among collegiate and semi-professional contact sport athletes, and compare these changes to differences in S100B before and after non-contact exertion.Study DesignLongitudinal cohort study.MethodsFrom 2009–2011, we performed a prospective study of athletes from Munich, Germany, and Rochester, New York, USA. Serum S100B was measured in all SRC athletes at pre-season baseline, within 3 hours of injury, and at days 2, 3 and 7 post-SRC. Among a subset of athletes, S100B was measured after non-contact exertion but before injury. All samples were collected identically and analyzed using an automated electrochemiluminescent assay to quantify serum S100B levels.ResultsForty-six athletes (30 Munich, 16 Rochester) underwent baseline testing. Thirty underwent additional post-exertion S100B testing. Twenty-two athletes (16 Rochester, 6 Munich) sustained a SRC, and 17 had S100B testing within 3 hours post-injury. The mean 3-hour post-SRC S100B was significantly higher than pre-season baseline (0.099±0.008 µg/L vs. 0.058±0.006 µg/L, p = 0.0002). Mean post-exertion S100B was not significantly different than the preseason baseline. S100B levels at post-injury days 2, 3 and 7 were significantly lower than the 3-hour level, and not different than baseline. Both the absolute change and proportional increase in S100B 3-hour post-injury were accurate discriminators of SRC from non-contact exertion without SRC (AUC 0.772 and 0.904, respectively). A 3-hour post-concussion S100B >0.122 µg/L and a proportional S100B increase of >45.9% over baseline were both 96.7% specific for SRC.ConclusionsRelative and absolute increases in serum S100B can accurately distinguish SRC from sports-related exertion, and may be a useful adjunct to the diagnosis of SRC.

Determination of the phosphorylated neurofilament subunit NF-H (pNF-H) in cerebro-spinal fluid as biomarker in acute traumatic spinal cord injuries / Dozarea neurofilamentelor fosforilate (subunitatea pNF-H) ȋn LCR ca biomarker ȋn traumatismul vertebro-medular acut

“…in several experimental or human studies. But some of these were not significantly elevated in patients with SCI compared with patients without any neurologic lesions (cleavedTau) (28) or the detection of MBP in the CSF is lower (29) or some are also found in other cells, such as adipocytes (S100β) (30). Also, there are few clinical studies for the majority of them or there are problems related to their accessibility.…”

Blood biomarkers for brain injury: What are we measuring?

“…A number of other studies have shown an increase in serum S100β levels after concussion (Kiechle et al, 2014; Shahim et al, 2014) and even subconcussive head impacts. These reports have produced similar results, finding that mean S100β levels are 0.113 ± 0.052 ng/ml 1 h post-gameplay compared to pre-game means of 0.061 ± 0.019 ng/ml (Puvenna et al, 2014; Marchi et al, 2013).…”

“…However, poor association with other prognostic parameters raised questions regarding whether or not the increase in S100β was due to CNS-damage. Another recent study attempted to distinguish concussion-related elevations in serum S100β from the effects of exercise in contact sport athletes (Kiechle et al, 2014). First, pre-season baseline S100β levels were measured in 46 athletes.…”

What is the physiological time to recovery after concussion? A systematic review

“…Tau-C, but not Tau-A, was elevated after concussion; increased Tau-A at 144 hours was associated with persistent symptoms 69. S100b was increased 3 hours after concussion but not at days 2, 3, 7 or after exertion 71. Elevated glial fibrillar acidic protein was seen <24 hours postconcussion but not between 24 and 72 hours after injury; the change at <24 hours was associated with symptoms 72.…”