Prospective comparison of risk factors for firearm suicide and non-firearm suicide in a large population-based cohort of current and former US service members: findings from the Millennium Cohort Study.

Background: Suicide is a leading cause of death among service members and veterans. Among suicide methods, firearms are the most lethal and commonly used method among military populations. Limited research has compared risk factors for the various suicide methods. This study evaluated and compared risk factors for firearm versus non-firearm suicides using data from the Millennium Cohort Study, a large longitudinal military cohort. Methods: Using a competing risk approach, we identified factors associated with each suicide method. Risk factors included demographics, mental health diagnoses, mental health symptoms, military-specific characteristics, health behaviors, and psychosocial factors. Cause of death was assessed from July 1, 2001, through December 31, 2018. Findings: Among 201,565 eligible participants with a mean [SD] age of 29.0 [58.1] years, there were 139,789 (69.3%) male, 61,776 (30.7%) female, 15,927 (7.9%) Hispanic, 24,667 (12.3%) non-Hispanic Black, 14,138 (7.0%) Asian, Pacific Islander, American Indian or Multiracial, and 146,736 (72.8%) non-Hispanic White participants. During the study period, 330 died by firearm suicide and 168 died by non-firearm suicide. Overall, effect estimates for risk factors were similar across both methods of suicide. After adjustment, men (HR: 3.69, 95% CI: 2.59, 5.24) and those who screened positive for depression (HR: 1.97, 95% CI: 1.36, 2.87) had an elevated risk for firearm suicide. In contrast, those who self-reported a history of bipolar diagnosis (HR: 3.40, 95% CI: 1.76, 6.55) had significantly increased risk for non-firearm suicide. Interpretation: Findings suggest that prevention and intervention strategies overall may not need to be differentiated by specific demographic, military, or health factors. Targeted interventions that consider sex and mental health screens might have relative utility in preventing firearm related suicide risk compared with non-firearm suicide. Funding: Military Operational Medicine Research Program, Defense Health Program, and Department of Veterans Affairs.

Three-Item Dimensions of Anger Reactions Scale.

Importance: Problematic anger is prevalent and associated with adjustment difficulties in military populations. To facilitate measurement of problematic anger, a very brief valid measure is needed. Objective: To reduce the Dimensions of Anger Reactions 5-item (DAR-5) scale to a very brief measure. Design, Setting, and Participants: This cross-sectional study used survey data collected between 2014 and 2016 in the Australian Transition and Well-Being Research Programme and US Millennium Cohort Study. Participants were service members who were actively serving or had transitioned out of the military (separated). Statistical analyses were performed from September 2021 to June 2023. Main Outcomes and Measures: The DAR-5 was reduced to the 3 experiential items: frequency, intensity, and duration (the DAR-3). Psychometrics for the DAR-3 and DAR-5 were compared in terms of standardized Cronbach α, positive screening result, mean, and SD. Analyses were stratified by Australian and US military service status cohorts (active duty and separated). Results: A total of 71 010 participants were included from Australia and the US. Of 10 900 Australian participants (8145 active duty participants [74.7%]; 2755 separated participants [25.3%]), 5893 (55.2%) were aged 40 years or older and 8774 (80.5%) were male; of 60 110 US participants (24 706 active duty participants [41.1%]; 35 404 separated participants [58.9%]), 28 804 (47.9%) were aged 30 to 39 years and 43 475 (72.3%) were male. The DAR-3 demonstrated good internal consistency in the active duty (Australia: mean [SD] score, 4.97 [2.5]; α = 0.90; US: mean [SD] score, 5.04 [2.6]; α = 0.87) and separated (Australia: mean [SD] score, 6.53 [3.4]; α = 0.92; US: mean [SD] score, 6.05 [3.2]; α = 0.91) samples. The cutoff score of 8 or greater on the DAR-3 had optimal sensitivity and specificity across all samples. DAR-3 and DAR-5 were associated with posttraumatic stress disorder (PTSD), depression, aggression, and relationship conflict. While the scales did not significantly differ in their associations with PTSD, depression, and relationship conflict, the magnitude of association for aggression was significantly lower in US samples using the DAR-3 (eg, US active duty sample: DAR-5 OR, 9.96; 95% CI, 9.01-11.00; DAR-3 OR, 8.36; 95% CI, 7.58-9.22). Conclusions and Relevance: In this cross-sectional study of a very brief measure of anger, each item contributed to the overall strength of the measure without losing psychometric strength compared with the DAR-5. The consistency of these findings across military and veteran samples in Australian and US populations demonstrated the psychometric robustness of the DAR-3.

Racial, Ethnic, and Sex Disparities in Mental Health Among US Service Members and Veterans: Findings From the Millennium Cohort Study.

Although disparities in mental health occur within racially, ethnically, and sex-diverse civilian populations, it is unclear whether these disparities persist within US military populations. Using cross-sectional data from the Millennium Cohort Study (2014-2016; n = 103,184; 70.3% male; 75.7% non-Hispanic White), a series of logistic regression analyses were conducted to examine whether racial, ethnic, and/or sex disparities were found in mental health outcomes (posttraumatic stress disorder (PTSD), depression, anxiety, and problematic anger), hierarchically adjusting for sociodemographic, military, health-related, and social support factors. Compared with non-Hispanic White individuals, those who identified as American Indian/Alaska Native, non-Hispanic Black, Hispanic/Latino, or multiracial showed greater risk of PTSD, depression, anxiety, and problematic anger in unadjusted models. Racial and ethnic disparities in mental health were partially explained by health-related and social support factors. Women showed greater risk of depression and anxiety and lower risk of PTSD than men. Evidence of intersectionality emerged for problematic anger among Hispanic/Latino and Asian or Pacific Islander women. Overall, racial, ethnic, and sex disparities in mental health persisted among service members and veterans. Future research and interventions are recommended to reduce these disparities and improve the health and well-being of diverse service members and veterans.

Individual and Military Factors That Modify the Association Between Recent Sexual Trauma and Health Outcomes Among U.S. Service Members and Veterans.

Sexual trauma (ST), which includes both sexual harassment and sexual assault, is associated with a variety of adverse mental and physical health outcomes in military and civilian populations. However, little is known about whether certain individual or military attributes or prior experiences may modify the relationship between recent ST and mental or physical health outcomes. Data from a longitudinal cohort study of current and former military members were used to examine whether individual and military factors modify the association between recent ST and health outcomes (posttraumatic stress disorder, depression, multiple somatic symptoms, and insomnia). Results indicated that demographic (sex, sexual orientation, race/ethnicity) and military factors (service branch, service component, military separation) generally did not modify the main effect of ST on the outcomes examined. On the other hand, factors known to be protective (spirituality, social support) and risk factors (childhood trauma, combat deployment, and mental health status) did modify the effect of ST on multiple outcomes examined; notably, protective effects were diminished among those who experienced recent ST. Protective factors were associated with the lowest risk of adverse outcomes among those with no ST, while risk reduction was less among survivors of ST. Diminished impacts also were found for cumulative risk factors, with the influence of multiple individual risk factors associated with increased risk but in a subadditive manner. We conclude that the effect of recent ST on the outcomes examined was persistent in the presence of potential protective factors, but that it may be impacted by ceiling effects in combination with other risk factors.

Identifying at-risk marines: A person-centered approach to adverse childhood experiences, mental health, and social support.

BACKGROUND: Previous research indicates an association between adverse childhood experiences (ACES) and health outcomes; however, most of these studies rely on variable-centered techniques. This study implemented a person-centered approach to provide a more nuanced understanding of these relations. METHODS: The sample consisted of 3611 male Marines who completed two surveys, one prior to service and another during or after service. A series of latent class analyses were conducted to identify homogenous subgroups, using ACE categories as indicators. Hierarchical regressions were conducted to examine the relationships between classes, deployment experiences, depression and PTSD, and social support problems. RESULTS: Five classes were identified: Low Adversity (48.8 %), Low Adversity - Parental Separation (PS; 33.1 %), Elevated Adversity (7.0 %), Moderate Adversity - Violence/Safety (5.7 %), and Moderate Adversity - Parental Loss (PL; 5.4 %). Several classes were associated with outcomes; in reference to Low Adversity, Moderate Adversity - PL was associated with depression and PTSD, Elevated Adversity was associated with PTSD and social support problems, and Low Adversity - PS was associated with social support problems. Experiencing moderate to high combat appeared to modify the associations between Moderate Adversity - PL and depression and PTSD. LIMITATIONS: Study sample was limited to U.S. Marines; ACEs indicators were limited to specific categories, not allowing for a full range of potential childhood traumatic experiences. CONCLUSIONS: Findings suggest a nuanced connection between ACEs and mental health; using specific patterns of ACEs, particularly multifaceted indicators of adversity that are inclusive of parental absence may have more utility than the sheer number of ACEs as an indicator for those who may at a heightened risk for mental health concerns.

Contribution of post-trauma insomnia to depression and posttraumatic stress disorder in women service members: findings from the Millennium Cohort Study.

STUDY OBJECTIVES: We examined whether women service members and veterans who reported recent combat and/or sexual trauma experiences had a greater risk of insomnia compared with women who did not report these recent experiences, and whether insomnia would be associated with a greater risk of mental health outcomes. METHODS: We analyzed two waves of survey data (2011-2013, Time 1 [T1] and 2014-2016, Time 2 [T2]) from 26 443 current and former women service members from the Millennium Cohort Study. We assessed recent traumas in the past 3 years, and probable insomnia at T1 and probable post-traumatic stress disorder (PTSD) and depression at T2. A longitudinal mediation model was used to quantify separate indirect effects of recent traumas on mental health outcomes through probable insomnia. RESULTS: Women who had experienced recent sexual assault (odds ratio [OR] = 1.68; 95% CI = 1.24-2.10), sexual harassment (OR = 1.22; 95% CI = 1.05-1.41), and combat (OR = 1.34; 95% CI = 1.20-1.49) at T1 had a greater risk of probable insomnia at T1 compared with women who had not recently experienced these events. Probable insomnia at T1, in turn, was associated with probable depression (OR = 2.66; 95% CI = 2.31-3.06) and PTSD (OR = 2.57; 95% CI = 2.27-2.90) at T2. Recent combat experience did not moderate the associations of recent sexual trauma with insomnia or mental health outcomes. CONCLUSIONS: Insomnia contributes to the risk of subsequent mental health conditions following trauma. The diagnosis and treatment of post-trauma insomnia should be prioritized to mitigate the development of posttraumatic mental health conditions.

Pre-service factors associated with sexual misconduct among male U.S. Marines.

PURPOSE: Sexual assault is a prevalent and persistent problem in the military, yet few studies have examined predictors of sexual offenses. The study aim was to determine pre-service factors associated with sexual offense conviction among U.S. Marines. METHODS: This retrospective cohort study analyzed data from male active duty U.S. Marines (2003-2018). Pre-service factors were assessed using survey data from the Recruit Assessment Program, obtained prior to recruit training at the Marine Corps Recruit Depot, San Diego, California. These survey data were linked with sexual offense conviction data obtained from the Naval Criminal Investigative Service Consolidated Law Enforcement Operations Center. RESULTS: Of the 146,307 participants, the majority were 18-19 years old (66.7%) and non-Hispanic, White (62.1%) with a high school education or less (76.8%); 107 received convictions for a sexual offense. In unadjusted analyses, race and ethnicity, parental education, type of primary caregiver, parental death, family economic status, childhood emotional trauma, childhood physical abuse, childhood sexual abuse, and unprotected sex were associated with a sexual offense conviction. In the final multivariable model, race and ethnicity (American Indian/Alaskan Native, odds ratio [OR]: 5.28, 95% confidence interval [CI]: 1.86-14.98; Hispanic, OR: 1.83, 95% CI: 1.06-3.18; multiracial/other, OR: 3.28, 95% CI: 1.56-6.89), education (≤ high school, OR: 2.65; 95% CI: 1.21-5.80), parental death (OR: 2.27; 95% CI: 1.16-4.45), unprotected sex (OR: 1.78; 95% CI: 1.03-3.05), and school suspension/expulsion (OR: 1.64; 95% CI: 1.02-2.65) were significant predictors of a subsequent sexual offense conviction. CONCLUSIONS: Results underscore the importance of understanding factors associated with sexual offense and highlight the large discrepancy between self-reported estimates of sexual assault and sexual offense convictions. Findings may inform the development of effective strategies to reduce sexual misconduct, such as technology-facilitated programs that provide private, targeted education; supportive assistance; and prevention materials to individuals who may have elevated sexual misconduct risk.

Health Disparities Among Lesbian, Gay, and Bisexual Service Members and Veterans.

INTRODUCTION: This study investigated whether health disparities exist among lesbian, gay, and bisexual individuals serving in the U.S. military by examining the associations of sexual orientation with mental, physical, and behavioral health among a population-based sample of service members and veterans. METHODS: Sexual orientation and health outcomes were self-reported on the 2016 Millennium Cohort Study follow-up questionnaire (N=96,930). Health outcomes were assessed across 3 domains: mental health (post-traumatic stress disorder, depression, anxiety, binge eating, problematic anger), physical health (multiple somatic symptoms, physical functioning, BMI), and behavioral health (smoking, problem and risky drinking, insomnia). Adjusted logistic regression models conducted between 2019 and 2022 estimated the associations between sexual orientation and each health outcome. RESULTS: Lesbian, gay, and bisexual individuals (3.6% of the sample) were more likely to screen positive for post-traumatic stress disorder, depression, anxiety, binge eating, problematic anger, multiple somatic symptoms, and insomnia than heterosexual individuals. Gay/lesbian and bisexual women reported more adverse health outcomes (overweight and obesity, smoking, problem/risky drinking) than heterosexual women. Gay and bisexual men reported some adverse health outcomes (e.g., smoking and problem drinking) but better physical health (e.g., less overweight/obesity) than heterosexual men. CONCLUSIONS: Lesbian, gay, and bisexual service members reported poorer mental, physical, and behavioral health than heterosexual peers, most notably among gay/lesbian women and bisexual individuals. Findings suggest that lesbian, gay, and bisexual service members experience health disparities, despite many having equal eligibility for health care, highlighting the need for improved equity initiatives that promote cultural responsiveness, acceptance, and approaches to support the healthcare needs of lesbian, gay, and bisexual military members.

Association of Problematic Anger With Long-term Adjustment Following the Military-to-Civilian Transition.

Importance: Few studies have examined the role of problematic anger in long-term adjustment of service members transitioning out of the military. Objective: To determine the prevalence of problematic anger during the military-to-civilian transition period and the association of problematic anger with adjustment to civilian life. Design, Setting, and Participants: This cohort study used 2 waves of survey data administered approximately 5 years apart (time 1 [T1; September 26, 2014, to August 25, 2016] and time 2 [T2; October 23, 2019, to August 31, 2021]) from the Millennium Cohort Study, a population-based military study. Participants were US active-duty service members within 24 months of separating from military service at T1. Statistical analysis was performed from September 2021 to May 2022. Exposures: Problematic anger was operationalized as scoring at least 12 points on the 5-item Dimensions of Anger Reactions scale at T1. Main Outcomes and Measures: Behavioral and functional health (depression, posttraumatic stress disorder, problem drinking, functional limitations), relationship health (relationship quality, coping with parental demands, social support), and economic health (major financial problems, financial insecurity, homelessness, employment status) were assessed at T2. Covariates, assessed at T1, included demographics, military characteristics, mental health, problem drinking, and physical health. Results: Of the 3448 participants, 2625 (76.1%) were male, 217 (6.3%) were Hispanic, 293 (8.5%) were non-Hispanic Black, and 2690 (78.0%) were non-Hispanic White; the mean (SD) age was 40.1 (8.5) years; 826 (24.0%) met criteria for problematic anger. Prevalence of problematic anger was 15.9% (95% CI, 12.2%-19.7%) 24 months prior to military separation and 31.2% (95% CI, 26.2%-36.2%) 24 months following separation. After adjusting for covariates, problematic anger was associated with greater likelihood of behavioral and functional health outcomes (eg, posttraumatic stress disorder: adjusted odds ratio, 1.55, 95% CI, 1.23-1.96), relationship health difficulties (eg, low social support: aOR, 1.66; 95% CI, 1.23-2.24), and economic difficulties (eg, substantial financial insecurity: aOR, 1.64; 95% CI, 1.13-2.39) at T2. Conclusions and Relevance: This cohort study found an association between prevalence of problematic anger during the military-to-civilian transition and problematic anger with subsequent adjustment difficulties among US service members. These findings suggest the need to equip service members proactively with skills to identify and manage anger as a way to support them before and during this period of transition.

Combat exposure and behavioral health in U.S. Army Special Forces.

Although combat has been found to be associated with adverse health outcomes, little is known about the impact of specific combat exposures, particularly among specialized personnel. This study examined the association of different types of combat exposures with behavioral health outcomes, and whether these associations differed by Army occupational specialization: General Purpose Forces infantrymen (n = 5,361), Ranger Qualified infantrymen (n = 308), and Special Forces personnel (n = 593). Multivariable regression models estimated the association of combat severity, type of combat event (fighting, killing, threat to oneself, death/injury of others), and type of killing with mental health disorders, trouble sleeping, and problem drinking. Combat severity, each type of combat event, and killing noncombatants were associated with adverse health outcomes after adjusting for covariates and other combat exposures. Except for trouble sleeping, these associations did not differ by occupational specialization, though the prevalence and odds of outcomes were generally lower for Special Forces personnel.

Military service experiences and reasons for service separation among lesbian, gay, and bisexual individuals in a large military cohort.

BACKGROUND: The well-being of lesbian, gay, and bisexual (LGB) individuals is a topic of increasing concern within the military where significant institutional barriers, targeted aggression, and differential organizational policies such as "Don't Ask Don't Tell" have historically contributed to experiences of exclusion and discrimination. However, limited research has examined specific military and post-separation experiences among LGB service members and veterans. The goal of this study was to examine differences in military and service separation experiences by sexual orientation among a large representative sample of United States service members and veterans. METHODS: Survey data from the 2016 Millennium Cohort Study follow-up questionnaire were used to assess sexual orientation and multiple outcomes of interest: military experiences (morale, feelings about the military, missed workdays) and service separation experiences (reasons for separation, post-separation employment). The associations between sexual orientation (LGB versus heterosexual) and each of these outcomes were evaluated in a series of adjusted logistic regression models, stratified by sex when interactions were observed. RESULTS: Of the 99,599 participants, 3.4% identified as LGB. In adjusted models, LGB service members had significantly higher odds than heterosexual service members of feeling: unimpressed by the quality of unit leadership, unsupported by the military, and negative about the military overall. Bisexual women were more likely than heterosexual women to feel less unit camaraderie; both gay and bisexual men felt less camaraderie than heterosexual men. LGB veterans were more likely than heterosexual peers of the same sex to separate from service due to unplanned administrative reasons. Compared to heterosexual women, lesbian and bisexual women were more likely to separate from service due to dissatisfaction with promotions/pay and disability/medical reasons, while bisexual women specifically separated due to dissatisfaction with leadership and incompatibility with the military. Gay and bisexual men also reported separating due to incompatibility with the military, but only bisexual men were more likely to report separating due to disability/medical reasons compared to heterosexual men. CONCLUSIONS: Less positive military- and separation-specific experiences disproportionately affected LGB service members in this study. Promoting inclusion and increasing support for LGB service members may improve satisfaction with military service and retention.

Sexual Health Problems among Service Men: The Influence of Posttraumatic Stress Disorder.

Military operational stressors, such as combat exposure, may increase the risk of sexual health problems. This study examined factors associated with sexual health problems, and tested the mediating effect of probable posttraumatic stress disorder (PTSD) on the association between stressors (i.e., combat deployment and sexual assault) and sexual health problems among U.S. service men. Using multivariable logistic regression (n = 16,603) and Cox proportional hazards models (n = 15,330), we estimated the risk of self-reported sexual health difficulties and sexual dysfunction medical encounters, respectively. Mediation analyses examined the effect of probable PTSD as an intermediate factor between high combat deployment and sexual assault on sexual health problems. Approximately 9% endorsed sexual health difficulties and 8% had a sexual dysfunction. Risk factors for these sexual health problems included older age, lower education level, enlisted rank, disabling injury, certain medical conditions, and higher body mass index. Probable PTSD significantly mediated the associations between high combat with sexual health problems and sexual assault with sexual dysfunction. Additionally, high combat was directly associated with sexual health difficulties. These findings indicate a relationship between these stressors and sexual health problems which suggests that treatment options should be expanded, especially to include psychogenic sexual dysfunctions.

Problematic anger and economic difficulties: Findings from the Millennium Cohort Study.

BACKGROUND: The role of problematic anger in relation to economic difficulties is not well understood. This study examined the association of problematic anger with 4 elements of economic difficulties among service members and veterans. METHODS: Study participants (n = 95,895) were from the Millennium Cohort Study, and included U.S. service members and veterans; analyses were restricted to a Reserve/National Guard and/or veteran sample as appropriate. Key measures included the Dimensions of Anger Reactions scale and self-reported economic variables (involuntary job loss, financial problems, unemployment and homelessness). Covariates included demographics, military characteristics, disabling injury or illness, problem drinking, posttraumatic stress disorder, and major depressive disorder. The study design was cross-sectional. RESULTS: Among all participants, 17.4% screened positive for problematic anger, 29.7% reported involuntary job loss, and 6.4% reported financial problems. After adjustment for covariates, problematic anger was associated with involuntary job loss (AOR=1.28; 95% CI: 1.22, 1.33) and financial problems (AOR=1.46; 95% CI: 1.36, 1.57). Among veterans, 12.1% reported being unemployed; among Reserve/National Guard and veterans, 2.3% reported homelessness. Problematic anger was associated with unemployment (AOR=1.28, 95% CI: 1.18, 1.37) and homelessness (AOR=1.33; 95% CI: 1.16, 1.52) after adjusting for covariates. LIMITATIONS: The study relied on self-report data and directionality could not be established. CONCLUSIONS: Problematic anger was significantly associated with involuntary job loss, financial problems, unemployment and homelessness, even after adjusting for relevant covariates. These findings have clinical relevance in demonstrating the potential for targeting problematic anger in service members and veterans.

The Millennium Cohort Study: The first 20 years of research dedicated to understanding the long-term health of US Service Members and Veterans.

PURPOSE: The Millennium Cohort Study, the US Department of Defense's largest and longest running study, was conceived in 1999 to investigate the effects of military service on service member health and well-being by prospectively following active duty, Reserve, and National Guard personnel from all branches during and following military service. In commemoration of the Study's 20th anniversary, this paper provides a summary of its methods, key findings, and future directions. METHODS: Recruitment and enrollment of the first 5 panels occurred between 2001 and 2021. After completing a baseline survey, participants are requested to complete follow-up surveys every 3-5 years. RESULTS: Study research projects are categorized into 3 core portfolio areas (psychological health, physical health, and health-related behaviors) and several cross-cutting areas and have culminated in more than 120 publications to date. For example, some key Study findings include that specific military service-related factors (e.g., experiencing combat, serving in certain occupational subgroups) were associated with adverse health-related outcomes and that unhealthy behaviors and mental health issues may increase following the transition from military service to veteran status. CONCLUSIONS: The Study will continue to foster stakeholder relationships such that research findings inform and guide policy initiatives and health promotion efforts.

Combat Experience, New-Onset Mental Health Conditions, and Posttraumatic Growth in U.S. Service Members.

Objective: Studies examining posttraumatic growth (PTG) rely on surveys evaluating PTG in relation to prior traumatic experiences, resulting in psychometric problems due to the linkage of the dependent and independent variables. Few studies have assessed PTG following combat deployment while also controlling for mental health problems.Method: Longitudinal data on PTG, combat experience, and mental health were examined among U.S. Millennium Cohort Study deployers (n = 8732). Scores from a short-form (SF) version of the PTG inventory assessing current-state beliefs (C-PTGI-SF) independent of any predictor variables were assessed at time 1 (T1), before deployment, and change in scores were assessed approximately 3 years later after deployment at time 2 (T2). All participants screened negative for posttraumatic stress disorder (PTSD) and depression at T1.Results: Combat deployment severity was associated with a worsening of C-PTGI-SF scores at T2 among participants with moderate C-PTGI-SF scores at T1. A positive screen for comorbid PTSD/depression was associated with a worsening of C-PTGI-SF scores at T2 among participants with moderate or high C-PTGI-SF scores at T1. At T2, a strong inverse correlation was found between C-PTGI-SF scores and PTSD (r = -0.38) and depression (-0.41). Only 5% of participants who screened positive for a mental health problem at T2 (23/517) also experienced positive growth.Conclusions: These results challenge the clinical utility of the PTG construct. While PTG may be a useful framework for supporting trauma recovery on an individual basis, PTG does not appear to be distinct and independent from the negative psychological impact of traumatic experiences.

Sexual health difficulties among service women: the influence of posttraumatic stress disorder.

Background Sexual health among service women remains understudied, yet is related to health and quality of life. This study examined if the associations between recent combat and sexual assault with sexual health difficulties were mediated by mental disorders and identified factors associated with sexual health difficulties among service women. Methods Data from two time points (2013 and 2016) of the Millennium Cohort Study, a large military cohort, were used. The outcome was self-reported sexual health difficulties. Mediation analyses examined probable posttraumatic stress disorder (PTSD) and major depressive disorder (MDD) as intermediate variables between recent combat and sexual assault with the sexual health difficulties. Multivariable logistic regression modeling was used to examine the association of demographic, military, historical mental health, life stressors, and physical health factors with sexual health difficulties. Results Of the 6,524 service women, 13.5% endorsed experiencing sexual health difficulties. Recent combat and sexual assault were significantly associated with sexual health difficulties. Probable PTSD mediated the associations of recent combat and sexual assault with sexual health difficulties; probable MDD did not mediate these relationships. Other significant factors associated with sexual health difficulties included enlisted rank, historical mental disorders, childhood trauma, and disabling injury. Limitations Use of self-reported data, outcome not assessed using a standardized measure and future studies may benefit from examining other mediators. Conclusion Our findings that combat and sexual assault may have negative effects on service women's sexual health suggest that treatment options and insurance coverage for sexual health problems should be expanded.

Comparison of Posttraumatic Stress Disorder Checklist Instruments From Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition vs Fifth Edition in a Large Cohort of US Military Service Members and Veterans.

Importance: The definition of posttraumatic stress disorder (PTSD) changed markedly between the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) and DSM-5, creating challenges for studies and in medical settings spanning this transition. Objective: To evaluate the ability to compare and assess PTSD, based on DSM-IV and DSM-5 criteria, using PTSD Checklists (PCLs). Design, Setting, and Participants: This diagnostic study was conducted with survey data collected in October 2019, from the Millennium Cohort Study, a population-based US military cohort study. The population for the present study was restricted to a subset of initial web responders of the 2019 survey cycle, randomly assigned to 1 of 4 survey groups. Exposures: Each group received the DSM-IV and DSM-5 PCL (PCL-Civilian [PCL-C] version and PCL for DSM-5 [PCL-5]). PCL instruments were counterbalanced to control for order effects. Main Outcomes and Measures: Survey data were used to assess PTSD (using the PCL-C and PCL-5), major depressive disorder (using the Patient Health Questionnaire), generalized anxiety (using the Generalized Anxiety Disorder scale), and problem drinking (using the Patient Health Questionnaire). Demographic and military characteristics included age, sex, race/ethnicity, marital status, education, service branch, pay grade, enrollment panel, and military service status. Results: Among the 1921 participants (mean [SD] age, 50.1 [12.5] years), 1358 (70.7%) were men, 1638 (85.3%) were non-Hispanic White individuals, 1440 (75.0%) were married, and 1190 (61.9%) had at least a bachelor's degree; 295 (15.4%) had probable PTSD according to DSM-IV criteria with PCL-C compared with 286 (14.9%) using DSM-5 criteria with PCL-5 (κ = 0.77). There was substantial agreement between PCLs for probable PTSD based on DSM-IV criteria (295 [15.4%] with PCL-C; 316 [16.4%] with PCL-5; κ = 0.80) and DSM-5 criteria (286 [14.9%] with PCL-5; 258 [13.4%] with PCL-C; κ = 0.77). Estimated PTSD sum scores showed excellent agreement with observed scores. Using an established crosswalk, PCL-5 sum scores estimated with the PCL-C were similar to observed PCL-5 scores. Of the 17 corresponding items between the 2 instruments, 16 had substantial agreement. Appending 2 additional PCL-C items to the PCL-5 did not significantly alter estimates. The PCL-C and PCL-5 had nearly identical associations with comorbid conditions. Conclusions and Relevance: The findings of this diagnostic study suggest that PTSD can be successfully assessed and compared over time with either PCL instrument in veteran and military populations.

Behavioral health and sleep problems among US Army veterinarians and veterinary technicians participating in the Millennium Cohort Study.

OBJECTIVE: To determine the prevalences and relative odds of mental health problems, suicidal ideation, psychotropic medication use, problem drinking, trouble sleeping, and lack of social support among veterinarians and veterinary technicians, compared with other medical professionals, in the US Army. SAMPLE: 7,744 US Army personnel (957 officers [101 veterinarians and 856 physicians and dentists] and 6,787 enlisted personnel [334 veterinary technicians and 6,453 medics]) participating in the Millennium Cohort Study. PROCEDURES: Eligible participants completed ≥ 1 survey while serving as an Army veterinarian, veterinary technician, physician, general dentist, or medic. Analysis methods including multivariable logistic regression adjusted for covariates and stratified by pay grade were used to investigate associations between each health-care occupation and outcomes of interest. RESULTS: Veterinarians had higher reported prevalences of mental health problems, trouble sleeping, and lack of social support than did nontrauma physicians, trauma physicians, or dentists. On multivariable analysis, veterinarians had higher odds of mental health problems, trouble sleeping, and lack of social support, compared with physicians and dentists combined; odds for these outcomes were also higher for veterinarians, compared with various individual reference groups. Veterinary technicians had lower reported prevalence and lower odds of psychotropic medication use, compared with medics. CONCLUSIONS AND CLINICAL RELEVANCE: Further examination of Army policies and organizational structures related to veterinarians may be warranted, along with the development of policies and interventions designed to improve mental health, sleep quality, and social support among military veterinarians.

Association of Combat Experiences With Suicide Attempts Among Active-Duty US Service Members.

Importance: There is uncertainty about the role that military deployment experiences play in suicide-related outcomes. Most previous research has defined combat experiences broadly, and a limited number of cross-sectional studies have examined the association between specific combat exposure (eg, killing) and suicide-related outcomes. Objective: To prospectively examine combat exposures associated with suicide attempts among active-duty US service members while accounting for demographic, military-specific, and mental health factors. Design, Setting, and Participants: This cohort study analyzed data from the Millennium Cohort Study, an ongoing prospective longitudinal study of US service members from all military branches. Participants were enrolled in 4 phases from July 1, 2001, to April 4, 2013, and completed a self-administered survey at enrollment and every 3 to 5 years thereafter. The population for the present study was restricted to active-duty service members from the first 4 enrollment phases who deployed in support of the wars in Iraq and Afghanistan. Questionnaire data were linked with medical encounter data through September 30, 2015. Data analyses were conducted from January 10, 2017, to December 14, 2020. Exposures: Combat exposure was examined in 3 ways (any combat experience, overall combat severity, and 13 individual combat experiences) using a 13-item self-reported combat measure. Main Outcomes and Measures: Suicide attempts were identified from military electronic hospitalization and ambulatory medical encounter data using the International Classification of Diseases, Ninth Revision codes. Results: Among 57 841 participants, 44 062 were men (76.2%) and 42 095 were non-Hispanic White individuals (72.8%), and the mean (SD) age was 26.9 (5.3) years. During a mean (SD) follow-up period of 5.6 (4.0) years, 235 participants had a suicide attempt (0.4%). Combat exposure, defined broadly, was not associated with suicide attempts in Cox proportional hazards time-to-event regression models after adjustments for demographic and military-specific factors; high combat severity and certain individual combat experiences were associated with an increased risk for suicide attempts. However, these associations were mostly accounted for by mental disorders, especially posttraumatic stress disorder. After adjustment for mental disorders, combat experiences with significant association with suicide attempts included being attacked or ambushed (hazard ratio [HR], 1.55; 95% CI, 1.16-2.06), seeing dead bodies or human remains (HR, 1.34; 95% CI, 1.01-1.78), and being directly responsible for the death of a noncombatant (HR, 1.81; 95% CI, 1.04-3.16). Conclusions and Relevance: This study suggests that deployed service members who experience high levels of combat or are exposed to certain types of combat experiences (involving unexpected events or those that challenge moral or ethical norms) may be at an increased risk of a suicide attempt, either directly or mediated through a mental disorder.