Objective: To compare initial and recurrent concussions regarding average number of days between concussions, acute concussion symptoms and symptom resolution time, and return to play time.
Setting/Participants: High school athletes sustaining multiple concussions linked within sport seasons drawn from a large sports injury surveillance study.
Design: Retrospective analysis of longitudinal surveillance data.
Measures: Number of days between concussions, number of symptoms endorsed, specific symptoms endorsed, symptom resolution time, return to play time.
Results: Median time between initial and recurrent concussions was 21 days (interquartile range = 10-43 days). Loss of consciousness, the only significant symptom difference, occurred more frequently in recurrent (6.8%) than initial (1.7%) concussions (P = .04). No significant difference was found in the number of symptoms (P = .84) or symptom resolution time (P = .74). Recurrent concussions kept athletes from play longer than initial concussions (P < .0001); 26.6% of recurrent concussions were season ending.
Conclusions: We found that athletes' initial and recurrent concussions had similar symptom presentations and resolution time. Despite these similarities, athletes were restricted from returning to play for longer periods following a recurrent concussion, indicating clinicians are managing recurrent concussions more conservatively. It is probable that concussion recognition and management are superior now compared with when previous studies were published, possibly improving recurrent concussion outcomes.
Department of Epidemiology (Mr Currie and Dr Comstock) and Program for Injury Prevention, Education and Research (Mr Currie and Dr Comstock), Colorado School of Public Health, Aurora; Emergency Medicine, Pediatrics, University of Colorado School of Medicine, Aurora (Dr Comstock); Department of Communication, University of Colorado–Denver (Dr Fields); Concussion Legacy Foundation, Waltham, Massachusetts (Dr Cantu); Boston University School of Medicine, Boston, Massachusetts (Dr Cantu); and Emerson Hospital, Concord, Massachusetts (Dr Cantu).
Corresponding Author: Dustin W. Currie, MPH, Department of Epidemiology, Colorado School of Public Health, 13001 E 17th Pl, Mail Stop B119, Aurora, CO 80045 (Dustin.firstname.lastname@example.org).
The content of this report was funded in part by the Centers for Disease Control and Prevention grants R49/CE000674-01 and R49/CE001172-01. The authors also acknowledge the generous research funding contributions of the National Federation of State High School Associations, the National Operating Committee on Standards for Athletic Equipment, DonJoy Orthotics, and EyeBlack. In addition, the authors thank the Certified Athletic Trainers, who report data to High School RIO, without their dedication this research would not be possible.
The content of this report is solely the responsibility of the authors and does not necessarily represent the official views of the Center for Disease Control and Prevention or any of the other institutions that provided financial support for this research.
The authors have no conflicts of interest to disclose.