Keywords: symptoms, recovery, concussion

In this blog post, we will explain how collegiate student-athletes with concussion fit into four distinct ‘symptom profile’ groups. Our study, recently published in BJSM (1), included sport-related concussions (SRC) across five academic years 2015-2016/2019–2020 (n=1160) from the Ivy League–Big Ten Epidemiology of Concussion Study (Ivy-B1G Study) (2).

Why is this study important?

Clinical management of concussion, guided by symptom domain presentation is an important and evolving strategy in concussion care (3). Understanding the nature of symptom experiences (as affective vs vestibular, for example) more precisely guides rehabilitation efforts to combat persisting post-concussion symptoms. We recognize that symptoms represent important clinical characteristics related to concussion recovery timelines. However, prior investigations into how individual concussion symptoms may cluster together only identify and describe these symptom domains. In our previous work in the Ivy-B1G Study,4 we identified six symptom domains best describe how individual symptoms measured via the Sport Concussion Assessment Tool (SCAT) 22-symptom evaluation group together:

1) headache

2) vestibulo-ocular

3) sensory

4) cognitive

5) sleep

6) affective 

Our study here extends this work by investigating how these student-athletes with SRC fit into distinct clinical symptom profiles, representing how they experience multiple, concurrent symptom domains. We then examined whether certain symptom profiles are associated with speed of recovery. The role of sex in these relationships was also examined. Our findings provide guidance for targeted, symptom domain-specific treatments to manage concussion. Additionally, the symptom profiles we identified can be studied further, together with physical examinations to better understand how reported symptoms correspond to other clinically objective characteristics.

How did the study go about this?

We leveraged data from the Ivy-B1G Study and included SRCs across five academic years 2015-2016/2019–2020 (n=1160). From our previous work identifying six symptom domains,4 here, we performed an analysis that grouped collegiate student-athletes (mean age=19.8 years). together based on shared symptom domains, which we call ‘symptom profiles.’ Symptom profiles characterize how these athletes endorse concurrent symptom domains. We were interested in the outcomes time (in days) from SRC injury to symptom resolution, return to academics, and full play. We used statistical models to determine relationships between symptom profile and time to these outcomes, adjusting for available demographic and clinical characteristics previously shown to be related to concussion symptoms and/or recovery outcomes. We also investigated whether such relationships between symptom profile and outcomes were different by sex, given existing, conflicting evidence that concussion symptoms differ by sex.

What did the study find?

In our previous work in the Ivy-B1G Study, we found that a six-domain structure best represented our symptom data: 1) headache domain (headache, pressure, neck pain); 2) vestibulo-ocular domain (nausea, dizziness, blurred vision, balance); 3) sensory domain (sensitivity to light, sensitivity to noise); 4) cognitive domain (feeling slowed down, feeling in a fog, don’t feel right, difficulty concentrating, difficulty remembering, confusion); 5) sleep domain (fatigue, drowsiness, difficulty falling asleep); and 6) affective domain (more emotional, irritability, sadness, nervous or anxious).4 

Building upon this work – here, we found four symptom profiles emerged to characterize the ways in which the six symptom domains co-occur:

1. ‘Low’ on all symptom domains
2. ‘High’ on headache and sensory domains
3. ‘High’ on vestibulo-ocular, cognitive, and sleep domains
4. ‘High’ on all symptom domains

We also found that, compared with symptom profile 1 (low on all symptom domains), those with symptom profile 2 (headache and sensory), 3 (vestibulo-ocular, cognitive, and sleep) and 4 (high on all symptom domains) on average took a longer time to complete recovery than profile 1. Time to recovery outcomes across symptom profiles did not vary significantly by sex.

What are the key take-home points?

• Our study contributes new knowledge about symptoms after concussion by describing how collegiate student-athletes fit into four distinct groups, representing how they experience concurrent symptom domains (‘symptom profiles’).
• We found statistically significant differences in the timelines to recovery outcomes between symptom profiles 2-4 compared to symptom profile 1, and we found no evidence of interaction between symptom profile and sex. 
• Our findings support and inform the creation of targeted, symptom-domain-specific interventions in the management of concussion. Examples could include vestibular or eye therapy treatments targeting patients experiencing vestibulo-ocular symptoms, or engaging psychologists and psychiatrists to treat existing and/or exacerbated affective symptoms. Additionally, patients in the headache profile may benefit from aggressive medical and physical therapy care to address the aetiology of their headache. 
• Findings also inform efforts targeting prolonged recovery, including decisions regarding resource allocation in athletic medicine departments, and the organisation and mobilisation of clinical care teams aimed at personalised medicine for athletes with concussion. 

References

1. D’Alonzo BA, Schneider AL, Barnett IJ, et al. Concurrent symptom domains and associations with recovery timelines among collegiate athletes with sport-related concussion. Br J Sports Med. Dec 18 2024;doi:10.1136/bjsports-2024-108351
2. Putukian M, D’Alonzo BA, Campbell-McGovern CS, Wiebe DJ. The Ivy League-Big Ten Epidemiology of Concussion Study: A Report on Methods and First Findings. Am J Sports Med. Apr 2019;47(5):1236-1247. doi:10.1177/0363546519830100
3. Schneider KJ, Critchley ML, Anderson V, et al. Targeted interventions and their effect on recovery in children, adolescents and adults who have sustained a sport-related concussion: a systematic review. Br J Sports Med. Jun 2023;57(12):771-779. doi:10.1136/bjsports-2022-106685
4. D’Alonzo BA, Barnett IJ, Master CL, et al. Factor Structure and Measurement Invariance Across Sex of the Sport Concussion Assessment Tool Symptom Inventory. Clin J Sport Med. Nov 26 2024;doi:10.1097/JSM.0000000000001301

Coauthors/Contributors

Bernadette A. D’Alonzo, PhD, MPH

Department of Neurology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA

Department of Biostatistics, Epidemiology and Informatics, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA

Jason Womack, MD

Department of Family Medicine and Community Health

Rutgers University – Robert Wood Johnson Medical School, New Brunswick, NJ, USA

Anne E. Danbury, PhD, ATC

Division of Intercollegiate Athletics, University of Illinois Urbana Champaign, Champaign, Illinois, USA