Post-injury outcomes following non-sport related concussion: A CARE Consortium Study

Abstract

Context: Concussion research has primarily focused on sport-related mechanisms and excluded non-sport related mechanisms. In adult populations, non-sport related concussions (non-SRC) demonstrate worse clinical outcomes relative to sport-related concussions (SRC); however, there is limited research examining non-SRC in college-aged patients. Objective: Examine clinical outcomes in collegiate athletes with non-SRC compared to SRC and examine sex differences in outcomes within non-SRC. Design: Prospective cohort. Setting: Clinical setting Participants: A total of 3,500 athletes were included (n=555 non-SRC; 42.5% female) from colleges/universities and service academies participating in the National Collegiate Athletic Association-Department of Defense Concussion Assessment, Research, and Education (CARE) Consortium. Main Outcome Measures: Dichotomous outcomes (yes/no) included immediate reporting, mental status alterations, loss of consciousness (LOC), posttraumatic amnesia (PTA), retrograde amnesia (RGA), motor impairments, delayed symptom presentation, and requiring hospital transport. Continuous outcomes included symptom severity, days with concussion symptoms, and days lost to injury. Data were collected within 24-48 hours and at return-to-play. Adjusted relative risk (ARR) compared the likelihood of dichotomous outcomes by mechanism and by sex within non-SRC. Multivariate negative binomial regressions were used to assess group differences in continuous variables. Results: Athletes with non-SRC were less likely to report immediately (ARR=0.73, 95%CI=0.65-0.81) and more likely to report delayed symptom presentation (ARR=1.17, 95%CI=1.03-1.32), LOC (ARR=3.15, 95%CI=2.32-4.28), RGA (ARR=1.77, 95%CI=1.22-2.57), and motor impairment (ARR=1.45, 95%CI=1.14-1.84). Athletes with non-SRC reported greater symptom severity, more symptomatic days, and more days lost to injury (P<0.001) relative to SRC. Within non-SRC, female athletes reported with greater symptom severity, more symptomatic days, and more days lost to injury (P<0.03) compared to male athletes. Conclusions: Athletes with non-SRC had worse post-injury outcomes relative to SRC and females with non-SRC had worse recovery metrics relative to males. Our findings suggest that further investigation of individuals with non-SRC is needed to improve concussion reporting and management.