PCS encompasses a constellation of symptoms that commonly include headache, depression, difficulty concentrating, and fatigue.3 Little is known regarding the exact cause of PCS, but risk factors often cited in the literature include pre-morbid psychiatric illness, learning disability, migraine headaches, being female, and age. 

Multiple concussions have been implicated in the development of chronic traumatic encephalopathy (CTE), a progressive tauopathy,10 but it is unknown if PCS is a predictor of CTE. At present, PCS is a clinical diagnosis without a diagnostic biomarker and there is no evidence-based treatment. PCS sufferers often feel frustrated and helpless due to the difficulty in diagnosis and the absence of proven treatment. The purpose of the present study was to better characterize persisting PCS. We used the following criterion for the clinical diagnosis of PCS: the persistence of any symptom 3 months after concussion. The medical charts of 285 consecutive patients with the possible diagnosis of PCS were reviewed. Questionnaires were then sent to these patients to collect specific information about recovery from PCS. The aims were to determine differences between those who recovered from PCS and those who did not, and to identify potential factors that affect recovery time.