Relationship Between Transdiagnostic Dimensions of Psychopathology and Traumatic Brain Injury (TBI): A TRACK-TBI Study

Neuropsychiatric symptoms are common, comorbid, and often disabling for patients with traumatic brain injury (TBI). Identifying transdiagnostic symptom dimensions post-TBI may help overcome limitations of traditional psychiatric diagnoses and advance treatment development. We characterized the dimensional structure of neuropsychiatric symptoms at 2-weeks postinjury in n = 1,732 TBI patients and n = 238 orthopedic-injured trauma controls (OTC) from the Transforming Research and Clinical Knowledge in TBI (TRACK-TBI) study. Symptoms were reported on the Brief Symptom Inventory-18, Patient Health Questionnaire-9 Depression checklist, PTSD Checklist for DSM-5, PROMIS Pain Intensity scale, and Insomnia Severity Index. We established a novel factor model of neuropsychiatric symptoms and evaluated how 3 TBI severity strata and OTC patients differed in symptom severity. The final factor model had 6 first-order factors subsumed by 2 second-order factors: Internalizing (encompassing Depression, Anxiety, and Fear) and Somatic symptoms (Sleep, Physical, Pain). Somatic symptoms fit better as a correlated factor of (vs. a lower-order factor within) Internalizing. All symptom dimensions except for Pain were more severe in 1 or more TBI subgroups, as compared to the OTC group. Milder brain injury was generally associated with more severe symptoms, whereas more general injury severity (higher level of care, e.g., emergency department, intensive care unit) was associated with more pain. The findings indicate a broad factor resembling the internalizing factor of general psychopathology in traumatically injured patients, alongside a distinct somatic symptom factor. Brain injury, especially milder brain injury, may exacerbate liabilities toward these symptoms. These neuropsychiatric dimensions may help advance more precision medicine research for TBI.