Charles W. Hoge

Mild Traumatic Brain Injury in U.S. Soldiers Returning from Iraq

BACKGROUND An important medical concern of the Iraq war is the potential long-term effect of mild traumatic brain injury, or concussion, particularly from blast explosions. However, the epidemiology of combat-related mild traumatic brain injury is poorly understood. METHODS We surveyed 2525 U.S. Army infantry soldiers 3 to 4 months after their return from a year-long deployment to Iraq. Validated clinical instruments were used to compare soldiers reporting mild traumatic brain injury, defined as an injury with loss of consciousness or altered mental status (e.g., dazed or confused), with soldiers who reported other injuries. RESULTS Of 2525 soldiers, 124 (4.9%) reported injuries with loss of consciousness, 260 (10.3%) reported injuries with altered mental status, and 435 (17.2%) reported other injuries during deployment. Of those reporting loss of consciousness, 43.9% met criteria for post-traumatic stress disorder (PTSD), as compared with 27.3% of those reporting altered mental status, 16.2% with other injuries, and 9.1% with no injury. Soldiers with mild traumatic brain injury, primarily those who had loss of consciousness, were significantly more likely to report poor general health, missed workdays, medical visits, and a high number of somatic and postconcussive symptoms than were soldiers with other injuries. However, after adjustment for PTSD and depression, mild traumatic brain injury was no longer significantly associated with these physical health outcomes or symptoms, except for headache. CONCLUSIONS Mild traumatic brain injury (i.e., concussion) occurring among soldiers deployed in Iraq is strongly associated with PTSD and physical health problems 3 to 4 months after the soldiers return home. PTSD and depression are important mediators of the relationship between mild traumatic brain injury and physical health problems.

Prevalence of Mental Health Problems and Functional Impairment Among Active Component and National Guard Soldiers 3 and 12 Months Following Combat in Iraq

CONTEXT A growing body of literature has demonstrated the association of combat in Iraq and Afghanistan with postdeployment mental health problems, particularly posttraumatic stress disorder (PTSD) and depression. However, studies have shown varying prevalence rates of these disorders based on different case definitions and have not assessed functional impairment, alcohol misuse, or aggressive behavior as comorbid factors occurring with PTSD and depression. OBJECTIVES To (1) examine the prevalence rates of depression and PTSD using several case definitions including functional impairment, (2) determine the comorbidity of alcohol misuse or aggressive behaviors with depression or PTSD, and (3) compare rates between Active Component and National Guard soldiers at the 3- and 12-month time points following their deployment to Iraq. DESIGN Population-based, cross-sectional study. SETTING United States Army posts and National Guard armories. PARTICIPANTS A total of 18 305 US Army soldiers from 4 Active Component and 2 National Guard infantry brigade combat teams. INTERVENTIONS Between 2004 and 2007, anonymous mental health surveys were collected at 3 and 12 months following deployment. MAIN OUTCOME MEASURES Current PTSD, depression, functional impairment, alcohol misuse, and aggressive behavior. RESULTS Prevalence rates for PTSD or depression with serious functional impairment ranged between 8.5% and 14.0%, with some impairment between 23.2% and 31.1%. Alcohol misuse or aggressive behavior comorbidity was present in approximately half of the cases. Rates remained stable for the Active Component soldiers but increased across all case definitions from the 3- to 12-month time point for National Guard soldiers. CONCLUSIONS The prevalence rates of PTSD and depression after returning from combat ranged from 9% to 31% depending on the level of functional impairment reported. The high comorbidity with alcohol misuse and aggression highlights the need for comprehensive postdeployment screening. Persistent or increased prevalence rates at 12 months compared with 3 months postdeployment illustrate the persistent effects of war zone service and provide important data to guide postdeployment care.

Association of Posttraumatic Stress Disorder With Somatic Symptoms, Health Care Visits, and Absenteeism Among Iraq War Veterans

OBJECTIVE Studies of soldiers from prior wars conducted many years after combat have shown associations between combat-related posttraumatic stress disorder (PTSD) and physical health problems. The current Iraq war has posed a considerable PTSD risk, but the association with physical health has not been well studied. METHOD The authors studied 2,863 soldiers using standardized self-administered screening instruments 1 year after their return from combat duty in Iraq. RESULTS Among all participants, 16.6% met screening criteria for PTSD. PTSD was significantly associated with lower ratings of general health, more sick call visits, more missed workdays, more physical symptoms, and high somatic symptom severity. These results remained significant after control for being wounded or injured. CONCLUSIONS The high prevalence of PTSD and its strong association with physical health problems among Iraq war veterans have important implications for delivery of medical services. The medical burden of PTSD includes physical health problems; combat veterans with serious somatic concerns should be evaluated for PTSD.

Trends in Antibiotic Resistance Among Diarrheal Pathogens Isolated in Thailand Over 15 Years

Antibiotic resistance trends were examined for Shigella species, nontyphoidal Salmonella species, enterotoxigenic Escherichia coli (ETEC), and Campylobacter species isolates from indigenous persons and travelers in Thailand for up to 15 years. Resistance to trimethoprim-sulfamethoxazole was found in >90% of Shigella and 40% of ETEC and nontyphoidal Salmonella isolates. Resistance to nalidixic acid was found in 97%-100% of Shigella dysenteriae 1 strains isolated between 1992 and 1995. Ciprofloxacin resistance was detected in 1% of ETEC isolates in 1994 and 1995 and in one of 349 nontyphoidal Salmonella isolates in 1995. Ciprofloxacin resistance among Campylobacter species increased from zero before 1991 to 84% in 1995 (P < .0001). Azithromycin resistance was found in 7%-15% of Campylobacter isolates in 1994 and 1995, as well as 15% of ETEC and 3% of Salmonella isolates in 1995. Enteric pathogens in Thailand have developed resistance to virtually all antibiotics routinely used in the treatment of diarrhea, as well as the newer fluoroquinolone and macrolide classes of drugs.

Posttraumatic stress disorder and depression in battle-injured soldiers.

OBJECTIVE This study examined rates, predictors, and course of probable posttraumatic stress disorder (PTSD) and depression among seriously injured soldiers during and following hospitalization. METHOD The patients were 613 U.S. soldiers hospitalized following serious combat injury. Standardized screening instruments were administered 1, 4, and 7 months following injury; 243 soldiers completed all three assessments. Cross-sectional and longitudinal analyses of risk factors were performed. PTSD was assessed with the PTSD Checklist; depression was assessed with the Patient Health Questionnaire. Combat exposure, deployment length, and severity of physical problems were also assessed. RESULTS At 1 month, 4.2% of the soldiers had probable PTSD and 4.4% had depression; at 4 months, 12.2% had PTSD and 8.9% had depression; at 7 months, 12.0% had PTSD and 9.3% had depression. In the longitudinal cohort, 78.8% of those positive for PTSD or depression at 7 months screened negative for both conditions at 1 month. High levels of physical problems at 1 month were significantly predictive of PTSD (odds ratio=9.1) and depression at 7 months (odds ratio=5.7) when the analysis controlled for demographic variables, combat exposure, and duration of deployment. Physical problem severity at 1 month was also associated with PTSD and depression severity at 7 months after control for 1-month PTSD and depression severity, demographic variables, combat exposure, and deployment length. CONCLUSIONS Early severity of physical problems was strongly associated with later PTSD or depression. The majority of soldiers with PTSD or depression at 7 months did not meet criteria for either condition at 1 month.

Battlemind Debriefing and Battlemind Training as Early Interventions With Soldiers Returning From Iraq: Randomization by Platoon

Researchers have found that there is an increase in mental heath problems as a result of military-related traumatic events, and such problems increase in the months following return from combat. Nevertheless, researchers have not assessed the impact of early intervention efforts with this at-risk population. In the present study, the authors compared different early interventions with 2,297 U.S. soldiers following a year-long deployment to Iraq. Platoons were randomly assigned to standard postdeployment stress education, Battlemind debriefing, and small and large group Battlemind training. Results from a 4-month follow-up with 1,060 participants showed those with high levels of combat exposure who received Battlemind debriefing reported fewer posttraumatic stress symptoms, depression symptoms, and sleep problems than those in stress education. Small group Battlemind training participants with high combat exposure reported fewer posttraumatic stress symptoms and sleep problems than stress education participants. Compared to stress education participants, large group Battlemind training participants with high combat exposure reported fewer posttraumatic stress symptoms and lower levels of stigma and, regardless of combat exposure, reported fewer depression symptoms. Findings demonstrate that brief early interventions have the potential to be effective with at-risk occupational groups.

Risk factors associated with suicide in current and former US military personnel.

IMPORTANCE Beginning in 2005, the incidence of suicide deaths in the US military began to sharply increase. Unique stressors, such as combat deployments, have been assumed to underlie the increasing incidence. Previous military suicide studies, however, have relied on case series and cross-sectional investigations and have not linked data during service with postservice periods. OBJECTIVE To prospectively identify and quantify risk factors associated with suicide in current and former US military personnel including demographic, military, mental health, behavioral, and deployment characteristics. DESIGN, SETTING, AND PARTICIPANTS Prospective longitudinal study with accrual and assessment of participants in 2001, 2004, and 2007. Questionnaire data were linked with the National Death Index and the Department of Defense Medical Mortality Registry through December 31, 2008. Participants were current and former US military personnel from all service branches, including active and Reserve/National Guard, who were included in the Millennium Cohort Study (N = 151,560). MAIN OUTCOMES AND MEASURES Death by suicide captured by the National Death Index and the Department of Defense Medical Mortality Registry. RESULTS Through the end of 2008, findings were 83 suicides in 707,493 person-years of follow-up (11.73/100,000 person-years [95% CI, 9.21-14.26]). In Cox models adjusted for age and sex, factors significantly associated with increased risk of suicide included male sex, depression, manic-depressive disorder, heavy or binge drinking, and alcohol-related problems. None of the deployment-related factors (combat experience, cumulative days deployed, or number of deployments) were associated with increased suicide risk in any of the models. In multivariable Cox models, individuals with increased risk for suicide were men (hazard ratio [HR], 2.14; 95% CI, 1.17-3.92; P = .01; attributable risk [AR], 3.5 cases/10,000 persons), and those with depression (HR, 1.96; 95% CI, 1.05-3.64; P = .03; AR, 6.9/10,000 persons), manic-depressive disorder (HR, 4.35; 95% CI, 1.56-12.09; P = .005; AR, 35.6/10,000 persons), or alcohol-related problems (HR, 2.56; 95% CI, 1.56-4.18; P <.001; AR, 7.7/10,000 persons). A nested, matched case-control analysis using 20:1 control participants per case confirmed these findings. CONCLUSIONS AND RELEVANCE In this sample of current and former military personnel observed July 1, 2001-December 31, 2008, suicide risk was independently associated with male sex and mental disorders but not with military-specific variables. These findings may inform approaches to mitigating suicide risk in this population.

Care of war veterans with mild traumatic brain injury--flawed perspectives.

Researchers estimate that more than 300,000 U.S. veterans of the wars in Iraq and Afghanistan have sustained a mild traumatic brain injury. Dr. Charles Hoge, Herb Goldberg, and Carl Castro write that the clinical definition of “concussion/mild TBI” adopted by the Department of Defense and the VA is inadequate for achieving the objectives of their well-intentioned initiatives.

Post-combat invincibility : Violent combat experiences are associated with increased risk-taking propensity following deployment

Combat exposure is associated with increased rates of mental health problems such as post-traumatic stress disorder, depression, and anxiety when Soldiers return home. Another important health consequence of combat exposure involves the potential for increased risk-taking propensity and unsafe behavior among returning service members. Survey responses regarding 37 different combat experiences were collected from 1252 US Army Soldiers immediately upon return home from combat deployment during Operation Iraqi Freedom. A second survey that included the Evaluation of Risks Scale (EVAR) and questions about recent risky behavior was administered to these same Soldiers 3 months after the initial post-deployment survey. Combat experiences were reduced to seven factors using principal components analysis and used to predict post-deployment risk-propensity scores. Although effect sizes were small, specific combat experiences, including greater exposure to violent combat, killing another person, and contact with high levels of human trauma, were predictive of greater risk-taking propensity after homecoming. Greater exposure to these combat experiences was also predictive of actual risk-related behaviors in the preceding month, including more frequent and greater quantities of alcohol use and increased verbal and physical aggression toward others. Exposure to violent combat, human trauma, and having direct responsibility for taking the life of another person may alter an individuals perceived threshold of invincibility and slightly increase the propensity to engage in risky behavior upon returning home after wartime deployment. Findings highlight the importance of education and counseling for returning service members to mitigate the public health consequences of elevated risk-propensity associated with combat exposure.

An Epidemic of Pneumococcal Disease in an Overcrowded, Inadequately Ventilated Jail

BACKGROUND In the United States many correctional facilities now operate at far over capacity, with the potential for living conditions that permit outbreaks of respiratory infections. We investigated an outbreak that was identified in an overcrowded Houston jail after two inmates died of pneumococcal sepsis on the same day. Outbreaks of pneumococcal disease have been rare in the era of antibiotics. METHODS We assessed risk factors for pneumococcal disease in both a case-control and a cohort study. Ventilation was evaluated by measuring carbon dioxide levels and air flow to the living areas of the jail. The extent of asymptomatic infection was determined by culturing pharyngeal specimens from a random sample of inmates. Type-specific immunity was determined with an enzyme immunoassay. RESULTS Over a four-week period, 46 inmates had either acute pneumonia or invasive pneumococcal disease due to Streptococcus pneumoniae serotype 12F. The jails capacity had been set at 3500 inmates, but it housed 6700 at the time of the outbreak; the inmates had a median living area of only 34 ft2 (3.2 m2) (interquartile range, 28 to 56 ft2 [2.6 to 5.2 m2]) per person. There were significantly fewer cases of disease among inmates with 80 ft2 (7.4 m2) per person or more (P = 0.030). Carbon dioxide levels ranged from 1100 to 2500 ppm (acceptable, < 1000), and the ventilation system delivered a median of only 6.1 ft3 of outside air per minute per person (interquartile range, 4.4 to 8.5 ft3; recommended, > or = 20 ft3). The attack rate was highest among inmates in cells with the highest carbon dioxide levels and the lowest volume of outside air delivered by the ventilation system (relative risk, 1.94; 95 percent confidence interval, 1.08 to 3.48). Of underlying medical conditions, intravenous drug use was most strongly associated with disease (odds ratio, 4.50). The epidemic strain (serotype 12F) was cultured from 7 percent of the asymptomatic inmates. Of 11 case patients tested with the enzyme immunoassay, 9 (82 percent) lacked preexisting immunity to this strain. CONCLUSIONS Severe overcrowding, inadequate ventilation, and altered host susceptibility all contributed to this outbreak of pneumococcal disease in a large urban jail.