Suicide Attempts and Self-Inflicted Injury Among a National Cohort of Veterans with Post-Traumatic Stress Disorder and Traumatic Brain Injury

Background: Suicide rates are on the rise globally. Many suicide completers are previous attempters. Risk identification of attempters will provide an opportunity for prompt and targeted intervention towards suicide prevention. The aim of this study was to determine the incidence of suicide attempt and self-inflicted injury (SASI), and its associations with deployment-related PTSD and/or TBI and attempted suicide among a large national cohort of Veterans deployed pre and post-9/11 2001 who received care from the Veterans Health Administration (VHA) between 1998 - 2014. Methods: Clinical data from over 1,400 VHA establishments provided by the Veterans Administrations Informatics and Computing Infrastructure (VINCI) were used for descriptive and Cox regression analyses. Results: There were 1,327,604 patients in the study - PTSD only (1,121,818), TBI only (100,033), both PTSD and TBI (105,753). The incidence of SASI in the entire cohort was 351 per 100,000 person years; PTSD only (323), TBI only (181), both PTSD and TBI (835). Compared to TBI only group, the adjusted risk for SASI was higher in the PTSD only group (HR=1.129; 95% CI =1.063 - 1.200) and much higher in those with both PTSD and TBI (HR=2.283; 95% CI =2.136 - 2.441). The risk of SASI was higher if they were younger than 50 years, divorced or separated, non-Hispanic females, homeless, suffered adult abuse and neglect, had substance use, generalized anxiety and antisocial personality disorders, and if they were in the Pre-9/11 service period. Proportion of people attempting suicide increased every year post-diagnosis of PTSD and/or TBI. Conclusion: We recommend prioritizing resources to prevent suicide among at risk groups.