Faculty of Kinesiology & Physical Education, University of Toronto, Toronto, ON, Canada.
Defence Research and Development Canada, Toronto Research Centre, Toronto, ON, Canada.
PLoS One. 2020 Apr 28;15(4):e0232053. doi: 10.1371/journal.pone.0232053. eCollection 2020.
Increasing evidence suggests inflammation is an important component of concussion pathophysiology. However, its etiology, restitution, and potential clinical repercussions remain unknown. The purpose of the current study was to compare the blood concentrations of interleukin (IL) -6, a prominent inflammatory cytokine, between healthy athletes and athletes with a sport-related concussion (SRC), while addressing the potential confounds of sex, recent physical activity, and the interacting effect of concussion history.
A prospective, observational cohort study was conducted on athletes at a single academic institute participating across 13 interuniversity sports. Follow-up of 96 athletes who agreed to provide a blood sample was completed: 41 athletes with a physician diagnosed SRC, and 55 healthy athletes. Ella™, the high sensitivity immunoassay system by ProteinSimple was used to measure peripheral plasma concentrations of IL-6 within the first week (median = 4 days, range = 2-7) following injury. A resampled ordinary least squares regression was used to evaluate the relationship between IL-6 concentrations and concussion status, while partial least squares regression was used to evaluate the relationship between IL-6 and both symptom burden and time to clinical recovery.
Regression analysis identified a negative relationship between plasma IL-6 concentrations and the interaction between an acute SRC and a history of concussion (β = -0.29, p = 0.029). IL-6 did not differ between healthy athletes and those with an acute SRC independent of concussion history, and was not correlated with either recovery time or symptom burden in athletes with SRC.
Perturbations to circulating IL-6 concentrations, a key inflammatory cytokine, may be more pronounced following SRC in athletes who have a history of concussion. These results add to a growing body of evidence supporting the involvement of inflammation at all phases of recovery following SRC, and potentially support a concomitant effect of prior concussion on acute SRC pathophysiology.
越来越多的证据表明，炎症是脑震荡病理生理学的一个重要组成部分。然而，其病因、恢复和潜在的临床后果仍不清楚。本研究的目的是比较健康运动员和运动相关脑震荡（SRC）运动员之间的白细胞介素（IL）-6 血液浓度，同时解决性别、近期体力活动的潜在混杂因素以及脑震荡史的相互作用影响。
对单一学术机构的运动员进行了前瞻性观察队列研究，涉及 13 项校际运动。对同意提供血液样本的 96 名运动员进行了随访：41 名运动员被诊断为 SRC，55 名健康运动员。使用由 ProteinSimple 公司生产的高灵敏度免疫测定系统 Ella™在损伤后第一周（中位数=4 天，范围=2-7）内测量外周血浆中 IL-6 的浓度。使用重新取样的普通最小二乘回归评估 IL-6 浓度与脑震荡状态之间的关系，而偏最小二乘回归则用于评估 IL-6 与症状负担和临床恢复时间之间的关系。
回归分析确定了血浆 IL-6 浓度与急性 SRC 和脑震荡史之间的交互作用之间的负相关关系（β=-0.29，p=0.029）。IL-6 浓度在健康运动员和急性 SRC 运动员之间没有差异，与 SRC 运动员的恢复时间或症状负担无关。
在有脑震荡史的运动员中，循环中关键炎症细胞因子 IL-6 浓度的波动可能在 SRC 后更为明显。这些结果为越来越多的证据支持炎症在 SRC 后所有恢复阶段的参与提供了补充，并可能支持先前脑震荡对急性 SRC 病理生理学的协同影响。
