PTSD, Comorbidities, Gender, and Increased Risk of Cardiovascular Disease in a Large Military Cohort.

Importance: Posttraumatic stress disorder (PTSD) is a prevalent mental health problem that increases risk of cardiovascular disease (CVD). It is not known whether gender or comorbidities modify associations between PTSD and CVD. Objective: To assess risk of hypertension and atherosclerotic CVD (ASCVD) associated with PTSD in a predominantly young military population, and determine if gender or PTSD comorbidities modify these associations. Design setting and participants: Using administrative medical records, this longitudinal, retrospective cohort study assessed relationships of PTSD, gender, comorbidities (metabolic risk factors [MRF], behavioral risk factors [BRF], depression, and sleep disorders) to subsequent hypertension and ASCVD among 863,993 active-duty U.S. Army enlisted soldiers (86.2% male; 93.7%

Toward personalized care for insomnia in the US Army: a machine learning model to predict response to cognitive behavioral therapy for insomnia.

STUDY OBJECTIVES: The standard of care for military personnel with insomnia is cognitive behavioral therapy for insomnia (CBT-I). However, only a minority seeking insomnia treatment receive CBT-I, and little reliable guidance exists to identify those most likely to respond. As a step toward personalized care, we present results of a machine learning (ML) model to predict CBT-I response. METHODS: Administrative data were examined for n = 1,449 nondeployed US Army soldiers treated for insomnia with CBT-I who had moderate-severe baseline Insomnia Severity Index (ISI) scores and completed 1 or more follow-up ISIs 6-12 weeks after baseline. An ensemble ML model was developed in a 70% training sample to predict clinically significant ISI improvement (reduction of at least 2 standard deviations on the baseline ISI distribution). Predictors included a wide range of military administrative and baseline clinical variables. Model accuracy was evaluated in the remaining 30% test sample. RESULTS: 19.8% of patients had clinically significant ISI improvement. Model area under the receiver operating characteristic curve (standard error) was 0.60 (0.03). The 20% of test-sample patients with the highest probabilities of improvement were twice as likely to have clinically significant improvement compared with the remaining 80% (36.5% vs 15.7%; χ21 = 9.2, P = .002). Nearly 85% of prediction accuracy was due to 10 variables, the most important of which were baseline insomnia severity and baseline suicidal ideation. CONCLUSIONS: Pending replication, the model could be used as part of a patient-centered decision-making process for insomnia treatment. Parallel models will be needed for alternative treatments before such a system is of optimal value. CITATION: Gabbay FH, Wynn GH, Georg MW, et al. Toward personalized care for insomnia in the US Army: a machine learning model to predict response to cognitive behavioral therapy for insomnia. J Clin Sleep Med. 2024;20(6):921-931.

Toward personalized care for insomnia in the US Army: development of a machine-learning model to predict response to pharmacotherapy.

STUDY OBJECTIVES: Although many military personnel with insomnia are treated with prescription medication, little reliable guidance exists to identify patients most likely to respond. As a first step toward personalized care for insomnia, we present results of a machine-learning model to predict response to insomnia medication. METHODS: The sample comprised n = 4,738 nondeployed US Army soldiers treated with insomnia medication and followed 6-12 weeks after initiating treatment. All patients had moderate-severe baseline scores on the Insomnia Severity Index (ISI) and completed 1 or more follow-up ISIs 6-12 weeks after baseline. An ensemble machine-learning model was developed in a 70% training sample to predict clinically significant ISI improvement, defined as reduction of at least 2 standard deviations on the baseline ISI distribution. Predictors included a wide range of military administrative and baseline clinical variables. Model accuracy was evaluated in the remaining 30% test sample. RESULTS: 21.3% of patients had clinically significant ISI improvement. Model test sample area under the receiver operating characteristic curve (standard error) was 0.63 (0.02). Among the 30% of patients with the highest predicted probabilities of improvement, 32.5.% had clinically significant symptom improvement vs 16.6% in the 70% sample predicted to be least likely to improve (χ21 = 37.1, P < .001). More than 75% of prediction accuracy was due to 10 variables, the most important of which was baseline insomnia severity. CONCLUSIONS: Pending replication, the model could be used as part of a patient-centered decision-making process for insomnia treatment, but parallel models will be needed for alternative treatments before such a system is of optimal value. CITATION: Gabbay FH, Wynn GH, Georg MW, et al. Toward personalized care for insomnia in the US Army: development of a machine-learning model to predict response to pharmacotherapy. J Clin Sleep Med. 2023;19(8):1399-1410.

Association of emotion reactivity and distress intolerance with suicide attempts in U.S. Army soldiers.

INTRODUCTION: Emotion reactivity (ER) and distress intolerance (DI) may be associated with increased suicide attempt (SA) risk among U.S. Army soldiers. METHOD: In this case-control study, 74 soldiers recently hospitalized for SA (cases) were compared with 133 control soldiers from the same Army installations selected based on either propensity score matching (n = 103) or reported 12-month suicide ideation (SI) (n = 30). Controls were weighted to represent the total Army population at the study sites and the subpopulation of 12-month ideators. Participants completed questionnaires assessing ER, DI, and other psychosocial variables. Logistic regression analyses examined whether ER and DI differentiated SA cases from the general population and from 12-month ideators before and after controlling for additional important risk factors (sociodemographic characteristics, stressors, mental disorders). RESULTS: In univariate analyses, ER differentiated SA cases from both the general population (OR = 2.5[95%CI = 1.7-3.6]) and soldiers with 12-month SI (OR = 2.5[95%CI = 1.3-4.6]). DI also differentiated cases from the general population (OR = 2.9[95%CI = 2.0-4.1]) and 12-month ideators (OR = 1.9[95%CI = 1.1-3.5]). These associations persisted after controlling for sociodemographic variables, stressors, and mental disorders. CONCLUSION: Findings provide evidence that higher ER and DI are associated with increased risk of SA among soldiers, even after adjusting for known risk factors. Prospective research with larger samples is needed.

Risk of suicide attempt in reserve versus active component soldiers during deployment to the wars in Iraq and Afghanistan.

INTRODUCTION: Little is known about the degree to which U.S. Army soldiers in the Reserve Components (Army National Guard and Army Reserve) and Active Component (Regular Army) differ with respect suicide attempt (SA) risk during high-stress times, such as deployment. METHOD: Using administrative person-month records of enlisted soldiers on active duty during 2004-2009, we identified 1170 soldiers with a medically documented SA during deployment and an equal-probability control sample of other deployed soldiers (n = 52,828 person-months). Logistic regression analyses examined the association of Army component (Guard/Reserve vs. Regular) with SA before and after adjusting for socio-demographic and service-related predictors. RESULTS: Guard/Reserve comprised 32.1% of enlisted soldiers and 19.7% of suicide attempters in-theater, with a SA rate of 81/100,000 person-years (vs. 157/100,000 person-years among Regular; rate ratio = 0.5 [95% CI = 0.5-0.6]). Risk peaked near mid-deployment for both groups but was consistently lower for Guard/Reserve throughout deployment. Guard/Reserve had lower odds of SA after adjusting for covariates (OR = 0.7 [95%CI = 0.6-0.8]). Predictors of SA were similar between components. CONCLUSIONS: Guard/Reserve and Regular soldiers had similar patterns and predictors of SA during deployment, but Guard/Reserve had lower risk even after controlling for important risk factors. Additional research is needed to understand the lower SA risk among Guard/Reserve in-theater.

Predictors of Suicide Attempt Within 30 Days After First Medically Documented Suicidal Ideation in U.S. Army Soldiers.

OBJECTIVE: The authors sought to identify predictors of imminent suicide attempt (within 30 days) among U.S. Army soldiers following their first documented suicidal ideation. METHODS: Using administrative data from the Army Study to Assess Risk and Resilience in Servicemembers, the authors identified 11,178 active-duty Regular Army enlisted soldiers (2006-2009) with medically documented suicidal ideation and no prior medically documented suicide attempts. The authors examined risk factors for suicide attempt within 30 days of first suicidal ideation using logistic regression analyses, including sociodemographic and service-related characteristics, psychiatric diagnoses, physical health care visits, injuries, and history of family violence or crime perpetration or victimization. RESULTS: Among soldiers with first documented suicidal ideation, 830 (7.4%) attempted suicide, 46.3% of whom (N=387) attempted suicide within 30 days (rate, 35.4 per 1,000 soldiers). Following a series of multivariate analyses, the final model identified females (odds ratio=1.3, 95% CI=1.0, 1.8), combat medics (odds ratio=1.6, 95% CI=1.1, 2.2), individuals with an anxiety disorder diagnosis prior to suicidal ideation (odds ratio=1.3, 95% CI=1.0, 1.6), and those who received a sleep disorder diagnosis on the same day as the recorded suicidal ideation (odds ratio=2.3, 95% CI=1.1, 4.6) as being more likely to attempt suicide within 30 days. Black soldiers (odds ratio=0.6, 95% CI=0.4, 0.9) and those who received an anxiety disorder diagnosis on the same day as suicidal ideation (odds ratio=0.7, 95% CI=0.5, 0.9) were less likely. CONCLUSIONS: Suicide attempt risk is highest in the first 30 days following ideation diagnosis and is more likely among women, combat medics, and soldiers with an anxiety disorder diagnosis before suicidal ideation and a same-day sleep disorder diagnosis. Black soldiers and those with a same-day anxiety disorder diagnosis were at decreased risk. These factors may help identify soldiers at imminent risk of suicide attempt.

Daily variation in sleep characteristics in individuals with and without post traumatic stress disorder.

BACKGROUND: Sleep disturbances are common in individuals with post traumatic stress disorder (PTSD). However, little is known about how daily variation in sleep characteristics is related to PTSD. This study examined the night-to-night and weekday versus weekend variation in sleep duration, sleep quality, trouble falling asleep, and difficulty staying asleep in individuals with and without PTSD. METHODS: Participants (N = 157; 80 with PTSD, 77 without PTSD) completed daily self-reports of their nighttime sleep characteristics for 15 consecutive days. Linear mixed models were used to examine the associations between the 7 days of the week and weekday versus weekend variation in sleep characteristics and PTSD. RESULTS: Individuals with PTSD reported shorter sleep duration, lower sleep quality, more trouble falling asleep, and more difficulty staying asleep than individuals without PTSD. The pattern of change across the week and between weekdays and weekends was different between those with and without PTSD for sleep quality and trouble falling asleep. Among those with PTSD, sleep duration, sleep quality, and trouble falling asleep differed across the 7 days of the week and showed differences between weekdays and weekends. For those without PTSD, only sleep duration differed across the 7 days of the week and showed differences between weekdays and weekends. Neither group showed 7 days of the week nor weekday versus weekend differences in difficulty staying asleep. CONCLUSIONS: On average those with PTSD had shorter sleep duration, poorer sleep quality, and greater trouble falling and staying asleep. In particular, the day of week variation in sleep quality and trouble falling asleep specifically distinguishes those with PTSD from those without PTSD. Our findings suggest that clinical care might be improved by assessments of sleep patterns and disturbances across at least a week, including weekdays and weekends. Future studies should explore the mechanisms related to the patterns of sleep disturbance among those with PTSD.

Sex Differences in US Army Suicide Attempts During the Wars in Iraq and Afghanistan.

OBJECTIVE: To examine sex differences in risk for administratively documented suicide attempt (SA) among US Army soldiers during the Iraq/Afghanistan wars. METHOD: Using administrative person-month records of Regular Army enlisted soldiers from 2004 to 2009, we identified 9650 person-months with a first documented SA and an equal-probability control sample (n=153,528 person-months). Person-months were weighted to the population and pooled over time. After examining the association of sex with SA in a logistic regression analysis, predictors were examined separately among women and men. RESULTS: Women (an estimated 13.7% of the population) accounted for 25.2% of SAs and were more likely than men to attempt suicide after adjusting for sociodemographic, service-related, and mental health diagnosis (MHDx) variables (odds ratio=1.6; 95% confidence interval, 1.5-1.7). Women with increased odds of SA in a given person-month were younger, non-Hispanic White, less educated, in their first term of enlistment, never or previously deployed (vs. currently deployed), and previously received a MHDx. The same variables predicted SA among men. Interactions indicated significant but generally small differences between women and men on 6 of the 8 predictors, the most pronounced being time in service, deployment status, and MHDx. Discrete-time survival models examining risk by time in service demonstrated that patterns for women and men were similar, and that women's initially higher risk diminished as time in service increased. CONCLUSIONS: Predictors of documented SAs are similar for US Army women and men. Differences associated with time in service, deployment status, and MHDx require additional research. Future research should consider stressors that disproportionately affect women.

Mental health care utilization and stigma in the military: comparison of Asian Americans to other racial groups.

Objective: To investigate race disparities in the US Military among Asian, White, Black, Native American and Other, seeking mental health care in the context of stigma defined by perceived damage to career.Design: Using 2008 survey data taken from US military personnel, mental disorders including depression, generalized anxiety disorder, suicidal ideation, suicidal attempt and post-traumatic stress disorder serious psychological distress (as defined in Kessler - 6), as well as seeking mental health care in past 12 months and stigma were dichotomized and weighted logistic regression models were used.Results: A significant race disparity existed in seeking mental health care when data were stratified by stigma and depression adjusted for demographic variables. Compared to Asians with depression that perceived stigma, Blacks were more likely to seek mental health care (OR with 95% confidence interval for Asians: 3.97[2.21, 7.15], Black: 9.25[6.02, 14.20], p < .005) adjusting for demographic variables. Similar results held for other mental disorders with the exception of suicide attempts and serious psychological distress. Compared to Asians with serious psychological distress who did not perceive stigma, only Whites were more likely to seek mental health care (OR for Asians: 3.27[2.15, 4.97], White: 6.47[4.60, 9.11], p < .005). Among those without a mental health disorder, regardless of the presence or absence of perceived stigma, there was no disparity between any two race groups in seeking mental health care.Conclusion: Among individuals having perceived stigma with mental health disorders, Asian American active-duty personnel may be less likely to use mental health care when compared to non-Asian peers.

Cannabinoid CB2 receptors mediate the anxiolytic-like effects of monoacylglycerol lipase inhibition in a rat model of predator-induced fear.

The endocannabinoid system is a key regulator of the response to psychological stress. Inhibitors of monoacylglycerol lipase (MGL), the enzyme that deactivates the endocannabinoid 2-arachidonoyl-sn-glycerol (2-AG), exert anxiolytic-like effects in rodent models via 2-AG-dependent activation of CB1 cannabinoid receptors. In the present study, we examined whether the MGL inhibitor JZL184 might modulate persistent predator-induced fear in rats, a model that captures features of human post-traumatic stress disorder. Exposure to 2,5-dihydro-2,4,5-trimethylthiazoline (TMT), a volatile chemical that is innately aversive to some rodent species, produced in male rats a long-lasting anxiety-like state that was measured 7 days later in the elevated plus maze test. Systemic administration of JZL184 [4, 8 and 16 mg/kg, intraperitoneal (IP)] 4 h before testing caused dose-dependent inhibition of MGL activity and elevation of 2-AG content in brain tissue. Concomitantly, the inhibitor suppressed TMT-induced fear behaviors with a median effective dose (ED50) of 4 mg/kg. A similar behavioral response was observed with another MGL inhibitor, KML29 (4 and 16 mg/kg, IP). Surprisingly, the effect of JZL184 was prevented by co-administration of the CB2 inverse agonist AM630 (5 mg/kg, IP), but not the CB1 inverse agonist rimonabant (1 mg/kg, IP). Supporting mediation of the response by CB2 receptors, the CB2 agonist JWH133 (0.3, 1 and 3 mg/kg, IP) also produced anxiolytic-like effects in TMT-stressed rats, which were suppressed by AM630. Notably, (i) JWH133 was behaviorally ineffective in animals that had no prior experience with TMT; and (ii) CB2 mRNA levels in rat prefrontal cortex were elevated 7 days after exposure to the aversive odorant. The results suggest that JZL184 attenuates the behavioral consequences of predator stress through a mechanism that requires 2-AG-mediated activation of CB2 receptors, whose transcription may be induced by the stress itself.

Self-injurious thoughts and behaviors that differentiate soldiers who attempt suicide from those with recent suicide ideation.

BACKGROUND: Risk for suicide attempt (SA) versus suicide ideation (SI) is clinically important and difficult to differentiate. We examined whether a history of self-injurious thoughts and behaviors (SITBs) differentiates soldiers with a recent SA from nonattempting soldiers with current/recent SI. METHODS: Using a unique case-control design, we administered the same questionnaire (assessing the history of SITBs and psychosocial variables) to representative U.S. Army soldiers recently hospitalized for SA (n = 132) and soldiers from the same Army installations who reported 30-day SI but did not make an attempt (n = 125). Logistic regression analyses examined whether SITBs differentiated attempters and ideators after controlling for previously identified covariates. RESULTS: In separate models that weighted for systematic nonresponse and controlled for gender, education, posttraumatic stress disorder, and intermittent explosive disorder, SA was positively and significantly associated with the history of suicide plan and/or intention to act (odds ratio [OR] = 12.1 [95% confidence interval {CI} = 3.6-40.4]), difficulty controlling suicidal thoughts during the worst week of ideation (OR = 3.5 [95% CI = 1.1-11.3]), and nonsuicidal self-injury (NSSI) (OR = 4.9 [95% CI = 1.3-18.0]). Area under the curve was 0.87 in a full model that combined these SITBs and covariates. The top ventile based on predicted risk had a sensitivity of 24.7%, specificity of 99.8%, and positive predictive value of 97.5%. CONCLUSIONS: History of suicide plan/intention, difficult to control ideation, and NSSI differentiate soldiers with recent SA from those with current/recent SI independent of sociodemographic characteristics and mental disorders. Longitudinal research is needed to determine whether these factors are prospectively associated with the short-term transition from SI to SA.

Post traumatic stress symptom variation associated with sleep characteristics.

BACKGROUND: Post traumatic stress disorder (PTSD) and sleep problems are highly related. The relationship between nighttime sleep characteristics and next day post traumatic stress symptoms (PTSS) is not well known. This study examined the relationship between the previous night's sleep duration, number of awakenings, sleep quality, trouble falling asleep, and difficulty staying asleep and PTSS the following day. METHODS: Using an ecological momentary assessment methodology, individuals with probable PTSD (N = 61) reported their nighttime sleep characteristics daily and PTSS four times per day for 15 days. Univariate and multivariate linear mixed models were used to examine the previous night's (within-subjects) and person's mean (between-subjects) associations between sleep characteristics and PTSS. RESULTS: The previous night's sleep duration (p < .001), sleep quality (p < .001), trouble falling asleep (p < .001), and difficulty staying asleep (p < .001) significantly predicted the next day's PTSS. When examined in a multivariate model including all characteristics simultaneously, previous night's sleep duration (p = .024), trouble falling asleep (p = .019), and difficulty staying asleep (p < .001) continued to predict PTSS, but sleep quality (p = .667) did not. When considering a person's mean, trouble falling asleep (p = .006) and difficulty staying asleep (p = .001) predicted PTSS, but only difficulty staying asleep (p = .018) predicted PTSS in a multivariate model. CONCLUSIONS: Among individuals with PTSD, the previous night's sleep duration, trouble falling asleep, and difficulty staying asleep predict next day PTSD symptoms. Interventions that facilitate falling and staying asleep and increase time slept may be important for treating PTSD.

Potential chemokine biomarkers associated with PTSD onset, risk and resilience as well as stress responses in US military service members.

Cytokines, including chemokines, are small secreted proteins, which specifically effect on the interactions and communications between cells. Pro-inflammatory cytokines are produced predominantly by activated macrophages and are involved in the upregulation of inflammatory reactions. Dysregulation of cytokines is associated with post-traumatic stress disorder (PTSD). Here, we use both before-and-after and case-control studies to search for potential chemokine biomarkers associated with PTSD onset, risk, and resilience as well as stress responses in US military service members deployed to Iraq and Afghanistan. Blood samples and scores of the PTSD Checklist (PCL) were obtained from soldiers pre- and post deployment (pre, post). Forty chemokines were measured using the Bio-Plex Pro Human Chemokine Panel Assays. The before-and-after analysis showed potential markers (CCL2, CCL15, CCL22, CCL25, CXCL2, and CXCL12) are associated with PTSD onset, and CCL3, CXCL11, and CXCL16 are related to stress response. The case-control study demonstrated that CCL13, CCL20, and CXCL6 were possible PTSD risk markers, and CX3CL1 might be a resilience marker. In addition, CCL11, CCL13, CCL20, and CCL25 were correlated with the PCL scores, indicating their association with PTSD symptom severity. Our data, for the first time, suggest that these dysregulated chemokines may serve as biomarkers for PTSD onset, risk, and resilience as well as stress responses, and may benefit developing approaches not only for PTSD diagnosis but also for PTSD treatment.

Factors Associated With Suicide Ideation in US Army Soldiers During Deployment in Afghanistan.

IMPORTANCE: Understanding suicide ideation (SI) during combat deployment can inform prevention and treatment during and after deployment. OBJECTIVE: To examine associations of sociodemographic characteristics, lifetime and past-year stressors, and mental disorders with 30-day SI among a representative sample of US Army soldiers deployed in Afghanistan. DESIGN, SETTING, AND PARTICIPANTS: In this survey study, soldiers deployed to Afghanistan completed self-administered questionnaires in July 2012. The sample was weighted to represent all 87 032 soldiers serving in Afghanistan. Prevalence of lifetime, past-year, and 30-day SI and mental disorders was determined. Logistic regression analyses examined risk factors associated with SI. Data analyses for this study were conducted between August 2018 and August 2019. MAIN OUTCOMES AND MEASURES: Suicide ideation, lifetime and 12-month stressors, and mental disorders were assessed with questionnaires. Administrative records identified sociodemographic characteristics and suicide attempts. RESULTS: A total of 3957 soldiers (3473 [weighted 87.5%] male; 2135 [weighted 52.6%] aged ≤29 years) completed self-administered questionnaires during their deployment in Afghanistan. Lifetime, past-year, and 30-day SI prevalence estimates were 11.7%, 3.0%, and 1.9%, respectively. Among soldiers with SI, 44.2% had major depressive disorder (MDD) and 19.3% had posttraumatic stress disorder in the past 30-day period. A series of analyses of the 23 grouped variables potentially associated with SI resulted in a final model of sex; race/ethnicity; lifetime noncombat trauma; past 12-month relationship problems, legal problems, and death or illness of a friend or family member; and MDD. In this final multivariable model, white race/ethnicity (odds ratio [OR], 3.1 [95% CI, 1.8-5.1]), lifetime noncombat trauma (OR, 2.1 [95% CI, 1.1-4.0]), and MDD (past 30 days: OR, 31.8 [95% CI, 15.0-67.7]; before past 30 days: OR, 4.9 [95% CI, 2.5-9.6]) were associated with SI. Among the 85 soldiers with past 30-day SI, from survey administration through 12 months after returning from deployment, 6% (5 participants) had a documented suicide attempt vs 0.14% (6 participants) of the 3872 soldiers without SI. CONCLUSIONS AND RELEVANCE: This study suggests that major depressive disorder and noncombat trauma are important factors in identifying SI risk during combat deployment.

Genetic association of FKBP5 with PTSD in US service members deployed to Iraq and Afghanistan.

Post-traumatic stress disorder (PTSD) is a debilitating mental disorder with a prevalence of more than 7% in the US population and 12% in the military. An interaction of childhood trauma with FKBP5 (a glucocorticoid-regulated immunophilin) has been reported to be associated with PTSD in the general population. However, there are few reports on the association of FKBP5 with PTSD, particularly in important high-risk population such as the military. Here, we examined the association between four single-nucleotide polymorphisms (SNPs; rs3800373, rs9296158, rs1360780, rs9470080) covering the FKBP5 gene and probable PTSD in US service members deployed to Iraq and Afghanistan, a high-risk military population (n = 3890) (Hines et al., 2014). We found that probable PTSD subjects were significantly more likely to carry the A-allele of rs3800373, G-allele of rs9296158, C-allele of rs1360780, and C-allele of rs9470080. Furthermore, the four SNPs were in one block of strong pairwise linkage disequilibrium (r = 0.91-0.96). Within the block there were two major haplotypes of CATT and AGCC (rs3800373-rs9296158-rs1360780-rs9470080) that account for 99% of haplotype diversity. The distribution of the AGCC haplotype was significantly higher in probable PTSD subjects compared to non-PTSD (p<.05). The diplotype-based analysis indicated that the AGCC carriers tended to be probable PTSD. In this study, we demonstrated the association between FKBP5 and probable PTSD in US service members deployed to Iraq and Afghanistan, indicating that FKBP5 might be a risk factor for PTSD.

Early First Deployment and Risk of Suicide Attempt Among First-term Enlisted Soldiers in the U.S. Army.

OBJECTIVE: We examined early first deployment and subsequent suicide attempt among U.S. Army soldiers. METHOD: Using 2004-2009 administrative data and person-month records of first-term, Regular Army, enlisted soldiers with one deployment (89.2% male), we identified 1,704 soldiers with a documented suicide attempt during or after first deployment and an equal-probability control sample (n = 25,861 person-months). RESULTS: Logistic regression analyses indicated soldiers deployed within the first 12 months of service were more likely than later deployers to attempt suicide (OR = 1.7 [95% CI = 1.5-1.8]). Adjusting for sociodemographic characteristics, service-related characteristics, and previous mental health diagnosis slightly attenuated this association (OR = 1.6 [95% CI = 1.5-1.8]). Results were not modified by gender, deployment status, military occupation, or mental health diagnosis. The population-attributable risk proportion for deploying within the first 12 months of service was 17.8%. Linear spline models indicated similar risk patterns over time for early and later deployers, peaking at month 9 during deployment and month 5 postdeployment; however, monthly suicide attempt rates were consistently higher for early deployers. CONCLUSIONS: Enlisted soldiers deployed within the first 12 months of service have elevated risk of suicide attempt during and after first deployment. Improved understanding of why early deployment increases risk can inform the development of policies and intervention programs.

Prospective study of polygenic risk, protective factors, and incident depression following combat deployment in US Army soldiers.

BACKGROUND: Whereas genetic susceptibility increases the risk for major depressive disorder (MDD), non-genetic protective factors may mitigate this risk. In a large-scale prospective study of US Army soldiers, we examined whether trait resilience and/or unit cohesion could protect against the onset of MDD following combat deployment, even in soldiers at high polygenic risk. METHODS: Data were analyzed from 3079 soldiers of European ancestry assessed before and after their deployment to Afghanistan. Incident MDD was defined as no MDD episode at pre-deployment, followed by a MDD episode following deployment. Polygenic risk scores were constructed from a large-scale genome-wide association study of major depression. We first examined the main effects of the MDD PRS and each protective factor on incident MDD. We then tested the effects of each protective factor on incident MDD across strata of polygenic risk. RESULTS: Polygenic risk showed a dose-response relationship to depression, such that soldiers at high polygenic risk had greatest odds for incident MDD. Both unit cohesion and trait resilience were prospectively associated with reduced risk for incident MDD. Notably, the protective effect of unit cohesion persisted even in soldiers at highest polygenic risk. CONCLUSIONS: Polygenic risk was associated with new-onset MDD in deployed soldiers. However, unit cohesion - an index of perceived support and morale - was protective against incident MDD even among those at highest genetic risk, and may represent a potent target for promoting resilience in vulnerable soldiers. Findings illustrate the value of combining genomic and environmental data in a prospective design to identify robust protective factors for mental health.

Risk Factors and Timing of Suicide Attempts among US Army Reserve Component Soldiers during Deployment to the Afghanistan and Iraq Wars: Results from Army Study to Assess Risk and Resilience in Servicemembers.

Objective: During the wars in Afghanistan and Iraq, suicidal behaviors increased among U.S. Army soldiers. Although Reserve Component (RC) soldiers (National Guard and Army Reserve) comprise approximately one third of those deployed in support of the wars, few studies have examined suicidal behaviors among these "citizen-soldiers". The objective of this study is to examine suicide attempt risk factors and timing among RC enlisted soldiers. Methods: This longitudinal, retrospective cohort study used individual-level person-month records from Army and Department of Defense administrative data systems to examine socio-demographic, service-related, and mental health predictors of medically documented suicide attempts among enlisted RC soldiers during deployment from 2004-2009. Data were analyzed using discrete-time survival models. Results: A total of 230 enlisted RC soldiers attempted suicide. Overall, the in-theater suicide attempt rate among RC soldiers was 81/100,000 person-years. Risk was highest in the fifth month of deployment (13.8 per 100,000 person-months). Suicide attempts were more likely among soldiers who were women (adjusted odds ratio, aOR = 2.5 [95% CI: 1.8-3.5]), less than high school educated (aOR = 1.8 [95% CI: 1.3-2.5]), in their first 2 years of service (aOR = 2.0 [95% CI: 1.2-3.4]), were currently married (aOR = 2.0 [95% CI: 1.5-2.7]), and had received a mental health diagnosis in the previous month (aOR = 24.7 [95% CI: 17.4-35.0]). Conclusions: Being female, early in service and currently married are associated with increased odds of suicide attempt in RC soldiers. Risk of suicide attempt was greatest at mid deployment. These predictors and the timing of suicide attempt for RC soldiers in-theater are largely consistent with those of deployed Active Component (Regular) soldiers. Results also reinforce and replicate the findings among Active Component soldiers related to the importance of a recent mental health diagnosis and the mid-deployment as a period of enhanced risk.

Association between leukocyte telomere length and hostility in US army service members.

Hostility is a common form of emotionally charged anger which can lead to maladaptive and unhealthy behaviors. Significant association between shortened telomeres and greater levels of hostility has been observed in civilian populations, but has not yet been comprehensively studied in military populations. Our study investigates the relationship between hostility, post-traumatic stress disorder (PTSD), and leukocyte telomere length (LTL) in a sample of United States Army Special Operations personnel (n = 474) who deployed to Iraq and/or Afghanistan as part of combat operations. Hostility was measured with five items from the Brief Symptom Inventory (BSI). PTSD was determined using the PTSD Checklist (PCL) total score. The LTL was assessed using quantitative polymerase chain reaction methods and regression analyses were conducted to determine the association of hostility and telomere length. PTSD subjects reported higher hostility scores compared with those without PTSD. Among the participants with PTSD, those with medium or high level of hostility had shorter LTL than those with low level hostility (P < 0.01). Stepwise regression indicated that hostility level and age, but not gender and PTSD, were negatively correlated with LTL. Univariate regression showed that total hostility score was negatively associated with LTL (CI= -0.06 to -0.002, Beta= -0.095, p < 0.039) as well as a significant correlation between LTL and hostility impulses (HI) (CI= -0.108 to -0.009, Beta= -0.106, p < 0.021) and hostility controlling (HC) (CI= -0.071 to -0.002, Beta= -0.095, p < 0.004). Multiple regression analyses revealed that, while HC has no significant association with LTL, HI was still negatively correlated with LTL (p = 0.021). Our data indicates that LTL is associated with HI levels. Prevention and treatment efforts designed to reduce hostility may help mitigate risk for LTL shortening, a process of cellular aging, and thus slow accelerated aged-related health outcomes.

Daily variation in post traumatic stress symptoms in individuals with and without probable post traumatic stress disorder.

BACKGROUND: Little is known about the extent to which post traumatic stress symptoms (PTSS) vary from day to day in individuals with post traumatic stress disorder (PTSD). This study examined the variation of PTSS by day of the week, and whether daily or day of week variation differs between individuals with and without probable PTSD. METHODS: Subjects (N = 80) were assessed for probable PTSD at enrollment. Using an ecological momentary assessment methodology, PTSS were assessed four times daily by self-report for 15 days. Linear mixed models were used to assess the relationship of PTSS and day of the week. RESULTS: PTSS varied across the seven days of the week among participants with PTSD (p = .007) but not among those without PTSD (p = .559). Among those with PTSD, PTSS were lowest on Saturday. PTSS were higher on weekdays (Monday through Friday) versus weekends (Saturday and Sunday) in those with PTSD (p = .001) but there were no weekday/weekend differences among those without PTSD (p = .144). These variations were not explained by sleep medication, caffeine or alcohol use. CONCLUSIONS: Among individuals with probable PTSD, post traumatic stress symptoms vary by the day of the week, with more symptoms on weekdays compared to weekends. Determination of the factors associated with the daily variation in PTSD symptoms may be important for further developing treatments for PTSD.