Electronic Thesis and Dissertation Repository

Thesis Format

Integrated Article


Doctor of Philosophy




Dickey, James P.


Symptomatology can overlap between concussions and common mental health conditions (MHCs) – such as anxiety, depression, and attention-deficit/hyperactivity disorder. Research determined that there can be an onset of new or worsening symptoms related to pre-existing MHCs in individuals post-concussion. Pre-existing MHCs may affect concussion outcomes. Therefore, the relationship between pre-existing MHCs and concussions was further examined. Study One examined the difference in symptom severity and number of symptoms reported at the initial clinical assessment for concussion for individuals with and without a pre-existing MHC. A chart review determined that individuals with anxiety or multiple MHCs had significantly more concussion symptoms and greater symptom severity than matched controls at their initial clinical assessment. Study Two investigated the time course to discharge between individuals with and without pre-existing MHCs, and the correlation between initial symptom assessment and days until discharge. A chart review determined that there was no significant difference in the number of clinical visits or days between initial assessment and discharge from the clinic. However, individuals with multiple MHCs had significantly more symptoms and greater symptom severity at initial assessment and when discharged than matched controls. Additionally, individuals with pre-existing anxiety had significantly greater symptom severity at initial assessment and when discharged than matched controls, and significantly more symptoms at time of discharge than matched controls. Study Three assessed the effect of MHCs on static balance and symptom reporting in non-concussed individuals. Using a force plate, pathlengths of the center of pressure of non-concussed individuals with and without self-reported MHCs was assessed to determine if, like a concussion, mental health conditions are associated with impaired balance performance. Individuals with multiple MHCs had significantly more symptoms on concussion symptom evaluations than control individuals. Additionally, participants with anxiety had significantly longer pathlengths, which indicated a worse balance performance, than other participants during bilateral stance trials. Therefore, a pre-existing MHC may affect symptom reporting and balance performance. Overall, these studies indicate a relationship between concussion outcomes and pre-existing MHCs that should be considered when diagnosing and monitoring concussed individuals.

Summary for Lay Audience

Concussions are caused by impacts to the head and impair brain function. Concussions can be diagnosed using one or multiple different assessment tools. Although each tool slightly varies in its assessment type – such as balance, coordination, eye tracking, and memory – they all evaluate symptoms. Concussion symptoms are not the same for all individuals but can include balance problems, difficulty concentrating, feeling like “in a fog”, fatigue, sadness, and feeling nervous or anxious. However, these symptoms often occur in individuals who have a mental health condition and are not concussed. For these individuals, concussions often lead to a worsening of symptoms. It is important to not only understand how a concussion may affect symptoms of mental health conditions, but how mental health conditions may affect concussion outcomes. This dissertation contains three studies. The first two studies reviewed data from concussed patients attending a sports medicine clinic for initial concussion assessment and monitoring. The third study collected balance performance data from non-concussed individuals using a force plate. All three studies assessed individuals for mental health conditions and assessed concussion-related symptoms and outcomes. This dissertation provides insights into the effects of pre-existing mental health conditions on concussion outcomes such as symptoms, balance deficits, and days until clinic discharge from concussion injury.

Creative Commons License

Creative Commons Attribution-No Derivative Works 4.0 License
This work is licensed under a Creative Commons Attribution-No Derivative Works 4.0 License.