Traumatic Brain Injury and Veteran Mortality After the War in Afghanistan

Abstract

On August 30, 2021, the last US military service members left Afghanistan, marking the end of America's longest war. It is important to continue to examine the impact of the war on service members, veterans, family members, clinicians, and health care systems. Traumatic brain injuries (TBIs) are often described as one of the signature injuries of the war. Estimates of TBI among service members who have returned from military operations in Iraq and Afghanistan vary moderately, which highlights the critical importance of TBI definitions and methods to ascertain TBI exposure. Estimates suggest that between 9% and 28% of service members experienced a TBI. 1 Complicating matters further, many veterans experienced 1 or more TBIs before their military service, thereby suggesting that military-related injuries may be neither the first nor the worst lifetime injury sustained.Regardless of the true prevalence of TBI, it is clear that TBI represents a major health care issue for veterans. Additional research is needed to understand the long-term health outcomes for veterans with TBIs. The results should guide clinical, research, and policy-based decisions.Within this context, the analyses by Howard and colleagues 2 represent a timely contribution examining the association of TBI severity with mortality among more than 2.5 million veterans serving after September 11, 2001 (9/11). These secondary analyses were conducted as part of a larger study designed to examine health trajectories over time. Therefore, Howard et al 2 were right to highlight their limitations; this was not a population-based cohort study of all post-9/11 TBI cases. Cases were required to have 3 or more years of Department of Defense (DoD) health care, and 2 or more years of Veterans Health Administration (VHA) care for those who entered the VHA; therefore, these results should be confirmed in future studies. The authors found that all-cause mortality was higher among post-9/11 military veterans compared with the general population, and the differences increased along with TBI severity, especially among older veterans. 2 Different patterns emerged when external causes of death (ie, accidents, suicide, and homicides), cancer, and cardiovascular disease were examined separately; rates of external causes of death were especially high among those with a moderate-to-severe TBI. The authors calculated excess death estimates. Although only 3% of the post-9/11 cohort had a moderateto-severe TBI, they accounted for 33.6% of total excess deaths. 2The study by Howard et al 2 highlights challenges identified early in the war as TBI evolved as a critical issue. How should TBI be defined? What methods should be used to ascertain TBI cases? Despite substantial progress on these issues, many researchers are forced to make trade-off decisions that balance feasibility with reference standard methods. These methodological issues create challenges for identifying the true rate of TBI, injury severity, and short-and long-term outcomes associated with such injuries (eg, mortalit...

Detangling the Association Between Traumatic Brain Injury, Mental Health, and Suicide in Active Duty Service Members

“…Of interest, the study by Izzy et al demonstrated striking time-to-event links to psychiatric comorbidities, with the mild TBI cohort developing depression, anxiety, and alcohol use disorder significantly sooner than those without history of TBI. Together with the work of Brenner and colleagues, these studies suggest that an at-risk maladaptive phenotype exists and requires early identification. In addition, a study by Wilder and colleagues used a patient claims data set of more than 11 000 participants and noted that 48% were later diagnosed with a mental illness within 3 years following their concussion .…”

“…Although the cohort was mostly younger men, the striking findings include marked increases in mental health diagnoses, most notably mood (increased 67.7% in active duty service members with TBI vs 37.5% in those without) and substance use disorders (increased 100% in active duty service members with TBI vs 14.5% in those without). Brenner et al 1 found that time to suicide was markedly faster among active duty service members with history of TBI compared with those without a history of TBI (21.3% faster; estimate, 0.787; 95% CI, 0.715-0.866), especially among individuals with new-onset substance use disorder (62.8% faster; estimate, 0.372; 95% CI, 0.322-0.433). This study underscores the burden of suicide and multidimensionality of suicide risk among military personnel and veterans.…”

“…In this study, Brenner and colleagues present a retrospective cohort analysis of active duty service members in the Department of Defense Substance Use and Psychological Injury Combat Study. This large study includes more than 860 000 active duty service members returning from deployment in Afghanistan or Iraq and is bolstered by uniform access to participant records.…”

“…This large study includes more than 860 000 active duty service members returning from deployment in Afghanistan or Iraq and is bolstered by uniform access to participant records. Of note, 12.6% of the cohort had documentation of at least 1 TBI, but this likely represents an underestimate, given diagnostic difficulty associated with this injury and limits of electronic medical record review . Brenner et al compared the onset of new behavioral health conditions over time between a matched sample of active duty service members with and without documented, military-identified TBI.…”

“…Of note, 12.6% of the cohort had documentation of at least 1 TBI, but this likely represents an underestimate, given diagnostic difficulty associated with this injury and limits of electronic medical record review . Brenner et al compared the onset of new behavioral health conditions over time between a matched sample of active duty service members with and without documented, military-identified TBI. Although the cohort was mostly younger men, the striking findings include marked increases in mental health diagnoses, most notably mood (increased 67.7% in active duty service members with TBI vs 37.5% in those without) and substance use disorders (increased 100% in active duty service members with TBI vs 14.5% in those without).…”