Effects of Iraq/Afghanistan Deployments on Major Depression and Substance Use Disorder: Analysis of Active Duty Personnel in the US Military

摘要

Objectives. Our objective was to analyze the association between deployment characteristics and diagnostic rates for major depression and substance use disorder among active duty personnel. Methods. Using active duty personnel serving between 2001 and 2006 (n?=?678?382) and deployment information from the Contingent Tracking System, we identified individuals diagnosed with substance use disorders and major depression from TRICARE health records. We performed logistic regression analysis to assess the effect of deployment location and length on these diagnostic rates. Results. Increased odds of diagnosis with both conditions were associated with deployment to Iraq or Afghanistan compared with nondeployed personnel and with Army and Marine Corps personnel compared with Navy and Air Force personnel. Increases in the likelihood of either diagnosis with deployment length were only observed among Army personnel. Conclusions. There were increased substance use disorders and major depression across services associated with combat conditions. It would be important to assess whether the public health system has adequate resources to handle the increasing need of mental health services in this population. The continuing presence of the US military in Iraq and Afghanistan has posed substantial mental health challenges to US military service members and mental health care systems. 1–7 Much media attention and research effort have focused on posttraumatic stress disorder (PTSD) among US servicemen returning from Iraq and Afghanistan (Operations Iraqi Freedom and Operations Enduring Freedom [OIF/OEF]) and less on other mental health outcomes. However, there are other mental health conditions that are more likely to be diagnosed among the active duty population, such as a substance use disorder, major depression, anxiety, and traumatic brain injury. Reports by the Mental Health Advisory Team (MHAT) have noted that the percentage of soldiers reporting symptoms of major depression and substance use disorders has been rising over the years, 6,7 and a recent Rand report pointed out the need to study these conditions as part of the broad spectrum of postdeployment mental health consequences. 3 Most of the studies on this topic used convenience samples and focused on soldiers and Marines, with little attention paid to Navy and Air Force personnel. Two studies using convenience samples of soldiers or Marines returning from Iraq found that about 20% of these personnel required mental health treatment, 15% had depression, and 10% to 12% reported having substance use disorder problems. 8,9 Reports by MHAT, also focusing on soldiers and Marines, noted an increasing rate of depression and overall mental health problems over the years, and that the rate was positively associated with combat level. 6,7 A similar finding was echoed in a recent study using a convenience sample of 1200 soldiers—the authors found that witnessing atrocities (between rival Iraqi factions) and experiencing a personal threat were associated with significantly higher rates of alcohol misuse. 10 The most recent MHAT report also noted that Army-enlisted personnel had higher rates of mental health problems than did Marine-enlisted personnel. 6 These studies, although providing important information on the prevalence of mental health problems of deployed active duty populations, did not provide appropriate comparison groups among the nondeployed. The lack of proper comparison groups complicated efforts to attribute observed mental health problems to specific deployment-related experiences without the capacity to investigate corresponding background rates among the nondeployed active duty population. Although PTSD was typically triggered by witnessing a traumatic event—which was also part of the criteria for being diagnosed with the condition—major depression and substance use disorder could often be triggered by other events among the nondeployed population. 11 A few studies included the nondeployed population and had mixed findings. Research based on the Millennium Cohort Study (MCS), 12,13 which used self-administered surveys and tracked both active duty personnel and those separated from the military, compared health outcomes for those deployed in support of the Iraq and Afghanistan wars with those not deployed. The MCS found that men and women deployed with combat exposure had, respectively, 1.32 and 2.13 times the odds of having depression compared with those not deployed 14 and found weak evidence of any impact of a combat deployment on drinking outcomes among active duty respondents. 15 Besides the MCS, 1 study, using a 2008 Department of Defense Health Related Behaviors Survey, found that service members with any combat deployment had significantly higher rates of heavy alcohol and cigarette use. 16 Finally, a study that examined the New Jersey Army National Guard members found previous deployment to be significantly linked to a higher rate of major depress