Substance Use Disorders and Clinical Management of Traumatic Brain Injury and Posttraumatic Stress Disorder

UBSTANCE USE DISORDERS, TRAUMATIC BRAIN INJURY (TBI), and posttraumatic stress disorder (PTSD) are commoninmilitaryandcivilianpopulations,andoften occur together. A substantial proportion of militarypersonnelmisusealcohol.AstudyoftheUKarmedforces 1 reported that 67% of men and 49% of women had scores of 8 or higher, defined as hazardous drinking, on the Alcohol UseDisordersIdentificationTest,comparedwith38%ofmen and16%ofwomeninthegeneralpopulation.Inapopulationbased cohort of US soldiers returning from service in Iraq, 2 11.8% reported alcohol misuse on a 2-item alcohol screening test. Recent military service is also associated with TBI, PTSD,anddepression.Ina2008survey, 3 19.5%ofUSarmed servicespersonnelreturningfromserviceinAfghanistanand Iraq reported experiencing a possible TBI, 18.5% met criteria for PTSD or depression, and 7.3% both reported a possible TBI and met criteria for PTSD or depression. By comparison, the lifetime prevalence of PTSD estimated for the general US population is 7.8%, and of those 51.9% of men and27.9%ofwomenhavealifetimeprevalenceofbothPTSD and alcohol abuse or dependence. 4 Substance use disorders, TBI, and PTSD may occur together for several reasons. Alcohol use, for example, may beacauseoraconsequenceofTBI.Studieshaveshownthat depending on the setting studied, 18% to 66% of patients with TBI have a history of alcohol abuse, 5 and one-third to one-half of persons with TBI are intoxicated at the time of their injuries. 6 This is not surprising, considering that alcohol use is a recognized risk factor for motor vehicle injuries, falls, and violence, all of which are important causes of TBI. Hazardous drinking may also persist after TBI. A recentAustralianstudy 5 reportedthathazardousdrinkinginitially decreased after the TBI event and then increased by 2 years postinjury to 25.4% of the cohort. Traumatic brain injury has been reported to be associated with PTSD, 7 and PTSD may be associated with sub