Fear Avoidance and Clinical Outcomes from Mild Traumatic Brain Injury.

Characterizing psychological factors that contribute to persistent symptoms after mild traumatic brain injury (MTBI) can inform early intervention. To determine whether fear avoidance, a known risk factor for chronic disability after musculoskeletal injury, is associated with worse clinical outcomes from MTBI, adults were recruited from four outpatient MTBI clinics and assessed at their first clinic visit (mean = 2.7, standard deviation = 1.5 weeks post-injury) and again four to five months later. Of 273 patients screened, 102 completed the initial assessment, and 87 returned for the outcome assessment. The initial assessment included a battery of questionnaires that measure activity avoidance and associated fears. Endurance, an opposite behavior pattern, was measured with the Behavioral Response to Illness Questionnaire. The multi-dimensional outcome assessment included measures of post-concussion symptoms (British Columbia Postconcussion Symptom Inventory), functional disability (World Health Organization Disability Assessment Schedule-12 2.0), return to work status, and psychiatric complications (MINI Neuropsychiatric Interview). A single component was retained from principal components analysis of the six avoidance subscales. In generalized linear modeling, the avoidance composite score predicted symptom severity (95% confidence interval [CI] for B = 1.22-6.33) and disability (95% CI for B = 2.16-5.48), but not return to work (95% CI for B = -0.68-0.24). The avoidance composite was also associated with an increased risk for depression (odds ratio [OR] = 1.76, 95% CI = 1.02-3.02) and anxiety disorders (OR = 1.89, 95% CI = 1.16-3.19). Endurance behavior predicted the same outcomes, except for depression. In summary, avoidance and endurance behavior were associated with a range of adverse clinical outcomes from MTBI. These may represent early intervention targets.