Sport-Related Concussion in Female Athletes: A Systematic Review

Abstract

Background: Female athletes are more susceptible to sport-related concussions (SRCs) and experience worse outcomes compared with male athletes. Although numerous studies on SRC have compared the outcomes of concussions in male and female athletes after injury, research pertaining to why female athletes have worse outcomes is limited. Purpose: To determine the factors that predispose female athletes to more severe concussions than their male counterparts. Study Design: Systematic review; Level or evidence, 3. Methods: A systematic review was performed according to PRISMA (Preferred Reporting Items for Systematic Meta-Analyses) guidelines. The MEDLINE, EMBASE, CINAHL, PsychINFO, and Cochrane Library databases were systematically searched on July 5 to July 20, 2018. Included were cohort, case-control, and cross-sectional studies that examined the effects of concussive and subconcussive head impacts in only female athletes of all ages, regardless of competition level. These studies were further supplemented with epidemiologic studies. Exclusion criteria included narrative reviews, single case reports, abstracts and letters to the editor, and studies related to chronic traumatic brain injury. Results: A total of 25 studies met the inclusion criteria. Female athletes appear to sustain more severe concussions than male athletes, due in part to a lower biomechanical threshold tolerance for head impacts. Additionally, concussions may alter the hypothalamic-pituitary-ovarian axis, resulting in worse symptoms and amenorrhea. Although females are more likely to report concussions than males, underreporting still exists and may result in concussions going untreated. Conclusion: This systematic review demonstrates that female athletes may be more susceptible to concussion, have prolonged symptoms after a concussion, and are more likely to report a concussion than their male counterparts. However, underreporting still exists among female athletes. Possible factors that put female athletes at a higher risk for concussions include biomechanical differences and hormonal differences. To effectively prevent, diagnose, and treat concussions in female athletes, more research is required to determine when and how such injuries are sustained. Despite sex-based differences in the clinical incidence, reporting behavior, and outcomes of SRCs, female athletes remain an understudied population, resulting in lack of sex-specific treatment guidelines for female athletes postinjury.

The Incidence, Cost, and Burden of Concussion in Women’s Rugby League and Rugby Union: A Systematic Review and Pooled Analysis

“…Three studies [14,15,73] utilised the athlete exposures (AEs) rate and two of these three studies [15,73] reported on match injuries. Other studies were reviewed but were excluded as they were not peer reviewed [75][76][77], reported on a specific injury [67,[78][79][80][81][82][83][84][85], did not stratify the results by sex [86][87][88][89][90], did not report concussions [12] or exposure rates [91], assessed injuries as a result of foul play [92], utilised a self-reporting survey [87,92,93], reported on the costs [52-55, 94, 95], reported previously included data [6,67,68,[96][97][98][99], or were reviews [1,3,4,9,[100][101][102]. Reviewer inter-rater reliability was assessed as strong (κ = 0.84; p < 0.0001) between two of the reviewers.…”

Subconcussive changes in youth football players: objective evidence using brain vital signs and instrumented accelerometers

“…Female athletes are particularly under-represented in concussion research despite demonstrating worse injury-related outcomes compared to male athletes. 37 Ongoing work by our group and others is expanding the scope of this work accordingly.…”

Elevated Serum Interleukin-1β Levels in Male, but not Female, Collision Sport Athletes with a Concussion History

“…It is increasingly recognized that biological sex plays a critical role in the pathophysiology of concussion, and that the neuroinflammatory response may differ between males and females. 22,23 Of particular relevance, one study similarly reported a sex-specific serum inflammatory profile chronically following concussion. 24 Males with a history of multiple concussions had higher serum levels of MCP-4 than those with no previous HOC.…”