The effect of deployment on the rate of major depression and substance abuse in active duty military from 2001-2006

Abstract

Operation Iraqi Freedom and Operation Enduring Freedom have affected the mental health of the U.S. military, as evidenced by an increasing trend in mental health illness. This thesis evaluates the effects of deployment history on major depression and substance abuse in the active duty population from 2001 to 2006. The research specifically evaluates cumulative effects of deployment (location, total days, frequency of separate tours) on major depression and substance abuse across the different branches of the military. Probit regressions were used to estimate the effects of deployment characteristics on the rate of major depression and substance abuse using 2001-2006 data from TRICARE and DMDC, and all models control for service members' demographic and service characteristics, as well as time trend. In general, the results support that deployments, especially to Iraq and Afghanistan, significantly affect the probability of active duty personnel across all services being diagnosed with major depression or substance abuse. Furthermore, personnel deployed only once under OEF/OIF have the highest probability of both conditions compared to those with multiple deployments, indicating a selection bias: those diagnosed were excluded from future deployments. Lastly, the risk of both conditions, in particular substance abuse, increases as cumulative days of deployment increases.