Concussions and Interpersonal Physical Violence Perpetration Among U.S. College Students

Introduction

Violence perpetration is a rising concern on college campuses, with upward of 5% of students reporting perpetrating interpersonal physical violence (Ganson et al. 2021a). Similarly, concussions continue to garner significant public and research attention given continued rise in prevalence (Haarbauer-Krupa et al. 2021; Veliz et al. 2021) and the many associated adverse behavioral and physical health outcomes (Manley et al. 2017; Trenchard et al. 2013). Prior research has shown that a concussion history is associated with violence and aggression among adolescents (Lowry et al. 2021) and adults (Mosti and Coccaro 2018).

However, research on the relationship between concussions and violence is lacking among college students. In addition, there remains little understanding on whether a greater number of lifetime concussions, including both diagnosed and undiagnosed concussions, is associated with physical violence perpetration. Therefore, the aim of this study was to determine the association between the number of lifetime concussions, both diagnosed and undiagnosed, and interpersonal physical violence perpetration among a national sample of U.S. college students.

Materials and Methods

Cross-sectional data from three survey years (2017–2020) of the national (U.S.) Healthy Minds Study (HMS) were analyzed. Colleges and universities elect to participate in HMS. At institutions with ≥4000 students, 4000 students are randomly recruited to participate in the survey; at institutions with <4000 students, all students are recruited. Overall response rates ranged were 23% in 2017–2018, 16% in 2018–2019, 16% in fall 2019, and 13% in spring 2020. HMS utilizes a module-based survey design that focuses on topics related to physical, social, and mental health domains. Given this design, only a select number of participants, representing five unique colleges and universities, were included in this analysis. HMS is approved by the Institutional Review Boards of all participating colleges and universities, and informed consent was obtained from all participants.

Lifetime concussion history was assessed using self-report from two items: Number of concussions “diagnosed by a medical professional” and number of “undiagnosed concussions.” Concussion was defined as “a change in brain function following a force to the head, which may be accompanied by temporary loss of consciousness, but is identified in awake individuals with measures of neurologic and cognitive dysfunction,” which is consistent with prior definitions (Sussman et al. 2018). Responses for all concussions variables were categorized as “none,” “1–2,” and “≥3.”

Interpersonal physical violence perpetration was measured using the question, “Over the past 12 months, did you strike or physically injure anyone? ‘Yes' or ‘No’.” This item has been used in prior research using HMS (Ganson et al. 2021a,b) and self-reported measures of such behaviors remains the standard for crime and delinquency research (Krohn et al. 2010).

Multiple logistic regression analyses were conducted in 2021 using Stata 16.1 with lifetime concussion history (diagnosed and undiagnosed) as the independent variables and interpersonal physical violence perpetration as the dependent variable, while adjusting for age, race/ethnicity, sexual orientation, highest parent education, any current sports participation, any alcohol use in the past 2 weeks, any illicit drug use (e.g., marijuana, cocaine, heroin, and opioids) in the past 30 days, depression score measured using the Patient Health Questionnaire 9-Item (Kroenke et al. 2001), and survey year, as suggested by prior research (Ganson et al. 2021a; Lowry et al. 2021; Manley et al. 2017; Trenchard et al. 2013). Analyses were stratified by gender (male, female; p for interaction <0.05) and included HMS preconstructed nonresponse sample weighting.

Results

The sample consisted of 2268 college participants. The mean age was 20.6 (standard deviation 1.9) years and consisted of 65.5% male and 31.4% non-white college participants. Among male participants, the prevalence of interpersonal physical violence perpetration was highest for those who reported three or more diagnosed (19.9%; p < 0.05) or three or more undiagnosed (20.8%; p < 0.001) lifetime concussions compared with those who reported none (Fig. 1).

OPEN IN VIEWER

FIG. 1.

Prevalence (%) of interpersonal physical violence perpetration in the past 12 months by number of lifetime concussions among male and female Healthy Minds Study participants (N = 2268). Differences between groups determined using Pearson chi-square tests. *p < 0.05; ***p < 0.001.

Similarly, male participants who reported experiencing three or more diagnosed lifetime concussions (adjusted odds ratio [AOR] 2.75, 95% confidence interval [CI] 1.02–7.43) and one to two undiagnosed lifetime concussions (AOR 2.04, 95% CI 1.13–3.70), or three or more lifetime undiagnosed concussions (AOR 2.80, 95% CI 1.23–6.64) had higher odds of interpersonal physical violence perpetration in the past 12 months (Table 1). Conversely, there were no statistically significant associations between lifetime concussion history and interpersonal physical violence perpetration in the past 12 months among females.

Discussion

The results from this study show that a lifetime concussion history is associated with interpersonal physical violence perpetration among male college students, adding to the growing list of adverse correlates of concussions (Manley et al. 2017; Trenchard et al. 2013). Although prior research has shown associations between concussions and violence and aggression among adolescents and adults (Lowry et al. 2021; Mosti and Coccaro 2018), this association remained understudied among college students, where prevalence of interpersonal physical violence perpetration is increasing (Ganson et al. 2021a).

This association was notable among male participants who reported a lifetime history of undiagnosed concussions, as well as male participants who reported three or more diagnosed or undiagnosed concussions. First, the association between an undiagnosed concussion history and interpersonal physical violence perpetration is concerning and may highlight that those most likely to perpetrate violence are not seeking medical attention after head injuries nor for concussion symptoms. Conversely, it may be that those who are being formally diagnosed with a concussion are receiving appropriate medical care that may prevent violence perpetration.

Second, the associations found in this study show that male participants who reported three or more lifetime concussions, either diagnosed or undiagnosed, had the highest unadjusted prevalence and odds of interpersonal physical violence perpetration. This association may be explained by an overall higher prevalence of physical violence perpetration among male college students (Ganson et al. 2021a), and the potential neurological changes that may result from concussions and overlap with physical violence perpetration (e.g., aggressive tendencies, emotion regulation difficulties, and impulsivity; Dailey et al. 2018; Ganson et al. 2021b; Mosti and Coccaro 2018).

Third, it is also possible that people who engage in risk behaviors (i.e., physical violence perpetration) may have a greater propensity for physical injury, such as concussions. Future research is needed to further explicate the associations found in this study, including both longitudinal and brain-imaging studies, as well as studies investigating associations between concussions and violence perpetration across groups at higher risk of violence perpetration.

Limitations include the use of self-report measures, which may increase reporting bias; the cross-sectional study design, which limits casual inferences; the potential for unmeasured confounders that may influence this relationship; and the low overall response rates and module-based survey design limiting external validity. Health care professionals, both on and off campus, should monitor for violent behavior among college students who report experiencing concussion symptoms. Campus wellness and health promotion efforts should encourage students to seek medical attention after a head injury to ensure proper diagnosis and treatment.

Data Availability Statement

The Healthy Minds Study is available to researchers. Please visit http://healthymindsnetwork.org for more information.