Group trends in posttraumatic stress disorder and suicidal ideation over the 10 years after traumatic brain injury among veterans/service members: A VA model systems study

OBJECTIVE: To identify group-based patterns in suicidal ideation (SI) and posttraumatic stress disorder (PTSD) symptoms over the first 10 years after traumatic brain injury (TBI) among Veterans and Service Members (V/SMs). SETTING: V/SMs enrolled in the Department of Veterans Affairs (VA) Polytrauma Rehabilitation Center (PRC) TBI Model Systems study who received inpatient rehabilitation at one of the VA's five PRCs. PARTICIPANTS: A sample of 1057 V/SMs with TBI who completed at least one Patient Health Questionnaire-9 (PHQ-9) item 9 (assessing suicidal ideation) and at least one PTSD Checklist-Civilian Version (PCL-C) at follow-up over the 10-year interval. DESIGN: A k-means cluster analysis was conducted to determine group-based patterns of covarying PTSD and SI, and demographics, injury characteristics, and prior suicide attempt were compared with analyses of variance and chi-squares. MAIN OUTCOMES AND MEASURES: Past 2-week SI was assessed using PHQ-9 item 9, and PTSD symptoms in the past month were assessed using PCL-C. RESULTS: Three group-based patterns emerged: low PTSD-low SI (Cluster 1); high PTSD-low SI (Cluster 2); and high PTSD and SI (Cluster 3). The low PTSD-low SI group comprised 62.2% of the sample and had the lowest functional independence at discharge and higher education. The high PTSD-low SI included the most married V/SMs preinjury. The highest risk group of V/SMs with both high PTSD and SI exhibited greater preinjury mental health vulnerabilities, including a higher proportion of preinjury and past-year suicide attempts which persisted at 2-, 5-, and 10-year follow-ups. This cluster also had a greater history of combat deployments and a higher representation of V/SMs identifying as Asian. CONCLUSIONS: Findings emphasize that PTSD plays a central role in the association with SI among V/SMs with TBI, highlighting the critical need of comprehensive mental health and suicide risk evaluation and treatment through chronic recovery after TBI.