Studies of symptoms after concussion have been focused heavily on athletic and military populations; generalizability to "civilians" has not recently been demonstrated. We selected cognitive symptoms as an important target to assess because of impact on school and employment. We evaluated cognitive complaints in a highly symptomatic (Rivermead Post-Concussion Symptoms Questionnaire [PCSQ], mean [M] = 29.5) civilian sample (n = 100; age: M = 41.4; 36 male/64 female; days post-injury: range 14-154, M = 51.4) of consecutive referrals to a concussion specialty clinic. The Behavior Rating of Executive Functions-Adult version (BRIEF-A) was used to assess subjective cognitive symptoms. Independent variables were prior neurologic and psychiatric history, current neurological symptoms, objective neuropsychological tests and several measures of depression (Beck Depression Inventory, Second Edition [BDI2]), anxiety (Beck Anxiety Inventory), and stress (Post-Traumatic Stress Checklist-Civilian form). No demographic characteristic, injury measure, or past or current neurological history had any association with cognitive symptoms. Prior psychiatric history (57% of patients) was associated with abnormal BRIEF-A. Cognitive tests were overall in the average range, with only mild and sporadic associations with BRIEF-A elevations. All psychological measures showed significant associations with BRIEF-A elevations. Regression analyses for the BRIEF-A revealed depression was the significant contributor (BDI2, β = 0.73) with prior psychiatric history (β = 0.16) and age (β = 0.14) accounting to a lesser extent. In this civilian cohort, subjective cognitive symptoms appear to be due to psychological distress (in particular, depression) and prior psychiatric history more than actual cognitive impairment or other presenting symptoms. These findings illuminate the importance of early diagnosis and treatment of mood/emotional symptoms after injury.
Keywords: cognition; concussion; depression; mild traumatic brain injury.