Postinjury Outcomes After 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-SRCs) demonstrated worse clinical outcomes compared with sport-related concussions (SRCs); however, investigations of non-SRCs in college-aged patients are limited.

Objectives: To examine clinical outcomes in collegiate athletes with non-SRCs compared with SRCs and explore sex differences in outcomes among collegiate athletes with non-SRCs.

Design: Prospective cohort study.

Setting: Clinical setting.

Patients or other participants: A total of 3500 athletes were included (n = 555 with non-SRCs, 42.5% female) from colleges or universities and service academies participating in the National Collegiate Athletic Association Department of Defense Concussion Assessment, Research and Education (CARE) Consortium.

Main outcome measure(s): Dichotomous outcomes (yes or no) consisted of immediate reporting, mental status alterations, loss of consciousness, posttraumatic amnesia, retrograde amnesia, motor impairments, delayed symptom presentation, and required hospital transport. Continuous outcomes were symptom severity, days with concussion symptoms, and days lost to injury. Data were collected within 24 to 48 hours of injury and at return to play. Adjusted relative risks (ARRs) compared the likelihood of dichotomous outcomes by mechanism and by sex within patients with non-SRCs. Multivariate negative binomial regressions were used to assess group differences in continuous variables.

Results: Athletes with non-SRCs 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), loss of consciousness (ARR = 3.15, 95% CI = 2.32, 4.28), retrograde amnesia (ARR = 1.77, 95% CI = 1.22, 2.57), and motor impairment (ARR = 1.45, 95% CI = 1.14, 1.84). Athletes with non-SRCs described greater symptom severity, more symptomatic days, and more days lost to injury (P < .001) compared with those who had SRCs. Within the non-SRC group, female athletes indicated greater symptom severity, more symptomatic days, and more days lost to injury (P < .03) than male athletes.

Conclusions: Athletes with non-SRCs had worse postinjury outcomes compared with those who had SRCs, and female athletes with non-SRCs had worse recovery metrics than male athletes. Our findings suggest that further investigation of individuals with non-SRCs is needed to improve concussion reporting and management.

Keywords: injury reporting; mild traumatic brain injuries; symptoms.

Figure 1

Adjusted relative risks (ARRs) and 95% CIs between non–sport-related concussions (n = 555) and sport-related concussions (n = 2945) for clinical outcomes after concussion, who gave the initial diagnosis, and who provided final clearance, controlling for sex and concussion history. The ARRs and 95% CIs not in contact with the vertical line at null value (1.00) were considered statistically significant.

Figure 2

For the non–sport-related concussion cohort only, adjusted relative risks (ARRs) and 95% CIs between male (n = 208) and female (n = 347) athletes for clinical outcomes after concussion, who gave the initial diagnosis, and who provided final clearance, controlling for concussion history. The ARRs and 95% CIs not in contact with the vertical line at null value (1.00) were considered statistically significant.