Personal Factors Associated With Postconcussion Symptoms 3 Months After Mild Traumatic Brain Injury.

Objective: To describe personal factors in patients with mild traumatic brain injury (MTBI) and 2 control groups and to explore how such factors were associated with postconcussion symptoms (PCSs).

Design: Prospective cohort study.

Setting: Level 1 trauma center and outpatient clinic.

Participants: Participants (N=541) included patients with MTBI (n=378), trauma controls (n=82), and community controls (n=81).

Main Outcome Measures: Data on preinjury health and work status, personality, resilience, attention deficit/hyperactivity, and substance use. Computed tomography (CT) findings and posttraumatic amnesia were recorded. Symptoms were assessed at 3 months with the British Columbia Postconcussion Symptom Inventory and labeled as PCS+ if ≥3 symptoms were reported or the total score was ≥13. Predictive models were fitted with penalized logistic regression using the least absolute shrinkage and selection operator (lasso) in the MTBI group, and model fit was assessed with optimism-corrected area under the curve (AUC) of the receiver operating characteristic curve.

Results: There were few differences in personal factors between the MTBI group and the 2 control groups without MTBI. Rates of PCS+ were 20.8% for the MTBI group, 8.0% for trauma controls, and 1.3% for community controls. In the MTBI group, there were differences between the PCS+ and PCS- group on most personal factors and injury-related variables in univariable comparisons. In the lasso models, the optimism-corrected AUC for the full model was 0.79, 0.73 for the model only including personal factors, and 0.63 for the model only including injury variables. Working less than full time before injury, having preinjury pain and poor sleep quality, and being female were among the selected predictors, but also resilience and some personality traits contributed in the model. Intracranial abnormalities on CT were also a risk factor for PCS.

Conclusions: Personal factors convey important prognostic information in patients with MTBI. A vulnerable work status and preinjury health problems might indicate a need for follow-up and targeted interventions.