Abstract
Objective: Following concussion, symptoms such as headache, dizziness, and fatigue may transiently worsen or reemerge with increased exertion or activity. Standardized tests have been developed to assess symptom increases following aerobic, cognitive, or vestibular/oculomotor challenge. Although neurophysiological mechanisms are proposed to underlie symptom increases following exertion, psychological factors such as anxiety and misinterpretation of normal bodily sensations may also play a role. In this study, we examined the contribution of psychological factors to symptom provocation testing outcomes.
Setting: Two outpatient concussion clinics in British Columbia, Canada.
Participants: Adults with persistent symptoms following concussion (N = 79; 62% women).
Design: In a single session, participants completed self-report questionnaires measuring the psychological factors of interest and underwent symptom provocation testing including aerobic (Buffalo Concussion Bike Test; BCBT), cognitive (National Institutes of Health Toolbox-Cognition Battery; NIHTB-CB), and vestibular/oculomotor (Vestibular/Ocular Motor Screening for Concussion; VOMS) challenge.
Main Measures: Psychological factors of interest included premorbid and current anxiety (Generalized Anxiety Disorder-7; GAD-7), catastrophizing (Pain Catastrophizing Scale-Adapted; PCS-A), fear avoidance behavior (Fear Avoidance Behavior after Traumatic Brain Injury; FAB-TBI), and somatization (Patient Health Questionnaire-15; PHQ-15). Our primary outcome variables were self-reported symptom change during each symptom provocation test.
Results: We found that current anxiety (B = 0.034; 95% CI = 0.003, 0.065), symptom catastrophizing (B = 0.013; 95% CI = 0.000, 0.026), fear avoidance behavior (B = 0.029; 95% CI = 0.008, 0.050), and somatization (B = 0.041; 95% CI = 0.007, 0.075) were associated with increased symptoms during the VOMS in univariate models adjusted for time postinjury but not in a multivariable model that included all covariates. The psychological variables of interest were not significantly related to symptom change during the BCBT or NIHTB-CB.
Conclusion: Our findings suggest that symptom provocation test failure should be interpreted with caution because it might indicate psychological maladjustment rather than lingering brain injury or incomplete neurophysiological recovery.