Racial, Ethnic, and Sex Differences in Eating Disorder Onset Among U.S. Military Service Members.

Bulimia nervosa (BN) and binge eating disorder (BED) are the most prevalent eating disorders (EDs) among military personnel. Although sex differences are noted in ED prevalence in military and civilian samples, mixed findings have emerged when evaluating racial and ethnic differences. The present study examined independent associations and interactions between sex, race, ethnicity, and probable BED and BN onset. The sample included 91,413 and 96,245 service members from the Millennium Cohort Study for BED and BN analyses, respectively. Up to four datapoints (from 2001-2013) were used to conduct longitudinal complementary log-log regression analyses, as participants were followed until the outcome occurred or until study completion. BN was more likely among women than men, and no sex difference emerged for BED onset. BN was more likely among Hispanic/Latinx, Multiracial, Black, and Asian/Pacific Islander (API) while BED was less likely among Black and API versus non-Hispanic/Latinx White (NHW) service members. Interactions revealed greater likelihood of BN in Hispanic/Latinx service members was driven by men. Additional efforts are needed amongst racially and ethnically diverse groups in preventing and detecting EDs in military personnel. Future intersectionality research could elucidate systemic inequities and other contributing factors to ED onset to inform prevention and treatment efforts.

Risk and Protective Factors of Probable Binge Eating Disorder in US Military Spouses: Findings From the Millennium Cohort Family Study.

Binge eating disorder (BED) is a public health concern that has received little research attention in military families. Further research is needed to identify risk and protective factors to inform intervention and prevention efforts. This longitudinal study examined predictors of probable BED in a sample of U.S. military spouses (N = 5,269). Data were derived from the Millennium Cohort Family Study, which included baseline assessments of risk and protective factors and a follow-up assessment of probable BED approximately 3 years later. Results of a multivariable logistic regression model indicated that spouses with probable posttraumatic stress disorder, adverse childhood experiences, or who were former smokers had increased risk of probable BED at follow-up. Spouses whose service member had a deployment with combat exposure, or had not deployed, had higher risk of probable BED than spouses whose service member deployed without combat exposure. Age >34 years was the only protective factor to emerge as significant in the adjusted model. Results highlighted the need for interventions to improve psychoeducation and coping skills in military spouses, which may mitigate BED symptoms stemming from military-related stressors (e.g., combat deployment) or prior trauma, especially once maladaptive coping mechanisms (e.g., smoking) have ceased.

Bidirectional Associations between Probable Eating Disorders and Mental Health Conditions Among Military Service Members and Veterans.

Although prior research has examined the prevalence of eating disorders (EDs) such as binge eating disorder (BED) and bulimia nervosa (BN) among military personnel, less is known regarding temporal associations between EDs and other mental health conditions. Using longitudinal data from 179,694 service members and veterans from the Millennium Cohort Study, temporal associations between EDs (BN, BED) and mental health conditions (posttraumatic stress disorder, anxiety, depression, and problem drinking) were investigated using a cross-lagged panel model approach. Results indicated consistent bidirectional associations between most mental health conditions and EDs; however, the magnitude of these cross-lagged associations varied across BN and BED. Cross-lagged effects of mental health conditions on subsequent BED were significantly stronger than BED to mental health condition cross-lagged effects. In contrast, cross-lagged effects of BN on subsequent mental health conditions were stronger than mental health conditions to BN. Preventive screening for those at risk for BN may have a stronger impact on mitigating downstream mental health conditions, while interventions among those with mental health conditions may play a greater role in eliminating maladaptive coping strategies including binge eating. Study findings underscore the importance of early detection of mental health conditions and EDs to maximize readiness among service members.

Prevalence and Risk Factors for the Development of Bulimia Nervosa and Binge Eating Disorder in a Large U.S. Military Cohort.

While bulimia nervosa (BN) and binge eating disorder (BED) are prevalent in military populations, an understanding of risk and protective factors is limited by a lack of longitudinal population-based epidemiological research. This study examined the prevalence of BN and BED among active duty service members and identified military and psychosocial factors associated with their development. Millennium Cohort Study participants were followed for up to 15 years and prevalence was ascertained using survey and electronic medical record data. Longitudinal multivariable logistic regression models evaluated risk factors associated with the development of bulimia nervosa (n=96,245) or binge eating disorder (n=113,733). Weighted prevalence estimates from survey data (range, 0.80%-4.80%) were higher than those from medical records (0.04%-0.14%). Military factors significantly associated with increased risk for BN and BED included active duty component (vs Reserve/Guard); serving in the Army, Marines, or Navy/Coast Guard (vs Air Force); and combat deployment (vs deployment without combat). Associated psychosocial factors included lack of social support, experiencing at least one life stressor, and screening positive for posttraumatic stress disorder or problem drinking. Findings highlight the critical need for disordered eating screening and prevention efforts that bolster coping skills, which can ultimately improve service member functioning and readiness.

Sleep health among US Navy afloat versus ashore personnel in the Millennium Cohort Study.

Despite emerging public concern regarding the sleep health of military personnel over the past two decades, there remains a dearth of research examining sleep health among naval personnel assigned to sea duty. This study examined sleep metrics (e.g. fatigue, short sleep duration) and mental (e.g. posttraumatic stress disorder, depression) and physical health (e.g. type 2 diabetes, bodily pain) outcomes among naval personnel with recent sea duty (i.e. afloat) compared with naval personnel with recent shore duty (i.e. ashore). Prevalence ratios and mean differences for all outcomes were estimated and adjusted for demographic and military variables, and subsequently stratified by obesity. Sleep metrics were similar between afloat and ashore sailors except for short sleep duration, while sailors with recent shore duty had poorer physical health compared with those with recent sea duty. Stratified analyses suggested naval personnel with obesity had a higher proportion of nearly all adverse sleep-related health outcomes than those without obesity. Among participants without obesity, afloat personnel were more likely to report very short sleep (≤ 5 hours) and fewer hours of average nightly sleep, but were less likely to report physical health outcomes compared with ashore personnel. These findings suggest potential differences in sleep metrics and sleep-related health outcomes between afloat and ashore naval personnel. Additional research examining sleep outcomes using more objective measures is required to further investigate these findings, which may inform strategies to foster consolidated sleep despite environmental and occupational challenges in order to maintain high-performing naval personnel.

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.

Partner Effects: Analyzing Service Member and Spouse Drinking Over Time.

INTRODUCTION: Excessive alcohol use is a significant problem in the military. Although there is a growing emphasis on family-centered alcohol prevention approaches, little is known about the interplay between partners' drinking behaviors. This study examines how service members and their spouses influence each other's drinking behavior over time and explores the complex individual, interpersonal, and organizational factors that may contribute to alcohol use. METHODS: A sample of 3,200 couples from the Millennium Cohort Family Study was surveyed at baseline (2011-2013) and follow-up (2014-2016). The research team estimated how much partners' drinking behaviors influenced one another from baseline to follow-up using a longitudinal structural equation modeling approach. Data analyses were conducted in 2021 and 2022. RESULTS: Drinking patterns converged between spouses from baseline to follow-up. Participants' own baseline drinking had a small but significant effect on changes in their partners' drinking from baseline to follow-up. Results from a Monte Carlo simulation showed that the longitudinal model could reliably estimate this partner effect in the presence of several potential sources of bias, including partner selection. The model also identified several common risk and protective factors for drinking shared by both service members and their spouses. CONCLUSIONS: Findings suggest that changing the drinking habits of one spouse could lead to a change in the drinking habits of the other, which supports family-centered alcohol prevention approaches in the military. Dual-military couples especially may benefit from targeted interventions because they face a higher risk of unhealthy alcohol consumption.

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.

The bi-directional relationship between post-traumatic stress disorder and obstructive sleep apnea and/or insomnia in a large U.S. military cohort.

OBJECTIVES: Determine if a bi-directional relationship exists between the development of sleep disorders (obstructive sleep apnea [OSA] and/or insomnia) and existing post-traumatic stress disorder (PTSD), and vice versa; and examine military-related factors associated with these potential relationships. DESIGN: Longitudinal analyses of a prospective representative U.S. military cohort. PARTICIPANTS: Millennium Cohort Study responders in 2011-2013 (Time 1 [T1]) and 2014-2016 (Time 2 [T2]) without insomnia or OSA at T1 (N = 65,915) or without PTSD at T1 (N = 71,256). MEASUREMENTS: Provider-diagnosed OSA, self-reported items for insomnia, provider-diagnosed PTSD, and current PTSD symptoms were assessed at T1 and T2. Adjusted multivariable models identified military-related factors associated with new-onset PTSD in those with OSA and/or insomnia, and vice versa. RESULTS: Self-reported history of provider-diagnosed PTSD without current symptoms at T1 was associated with new-onset OSA only and comorbid OSA/insomnia at T2, while current PTSD symptoms and/or diagnosis was associated with new-onset insomnia only. OSA/insomnia at T1 was consistently associated with newly reported PTSD symptoms or diagnosis except that insomnia only was not associated with newly reported provider-diagnosed PTSD. Military-related risk factors significantly associated with the bi-directional relationship for new-onset PTSD or OSA/insomnia included prior deployment with higher combat exposure and recent separation from the military; being an officer was protective for both outcomes. CONCLUSIONS: In this large military cohort, findings suggest that PTSD and OSA and/or insomnia are bi-directionally predictive for their development, which was sometimes revealed by health care utilization. Relevant military-related risk factors should be considered in efforts to prevent or treat PTSD and/or sleep disorders.

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.

Longitudinal Patterns of Military Spousal Alcohol Consumption: Findings From the Millennium Cohort Family Study.

OBJECTIVE: Alcohol use in the military is prevalent and has short- and long-term health, safety, and career consequences. Although several studies have examined service members' alcohol consumption, few have focused on alcohol use among military spouses. This study assessed factors at individual, interpersonal, and organizational levels to determine associations with risky alcohol use among military spouses. METHOD: Data from baseline and first follow-up of the Millennium Cohort Family Study were used (N = 5,475; 4,923 female) to model spousal self-reported risky drinking (heavy and/or binge drinking) at follow-up. Predictors included demographic characteristics, spousal adverse childhood experiences and mental health, smoking status, marital status, family satisfaction, social support, military stress, and service member military characteristics. Logistic regression models assessed the adjusted associations between spouse and service member characteristics and spousal risky drinking at follow-up. RESULTS: Among spouses in this sample, 19% were risky drinkers at follow-up. Baseline alcohol use status was associated with risky drinking at follow-up. Most spouses (64.2%) did not change their drinking behavior between baseline and follow-up; those who did change were nearly evenly split between an increasing (17.0%) versus decreasing (18.7%) pattern. Risk factors included male gender, cigarette smoking, elevated symptoms of post-traumatic stress, marital separation, and service member deployment with combat. CONCLUSIONS: Although most military spouses were not engaging in risky drinking, one in five were, with about half of these having moved into the risky drinking category over time. Risky alcohol use among spouses has ramifications for themselves, the service member, and the family unit.

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.

Association of deployment with maintenance of healthy weight among active duty service members in the Millennium Cohort Study.

Objective: Understanding body size in relation to deployment readiness can inform Department of Defense fitness policies. This study examined longitudinal associations between deployment and changes in body mass index (BMI) among active duty service members. Methods: Service branch-specific changes in BMI post-deployment were examined using logistic regression models among active duty Millennium Cohort Study participants without obesity at baseline (n = 22,995). BMI was categorized using self-reported height and weight as healthy weight (18.5-24.9 kg/m2), overweight (25.0-29.9 kg/m2), and obese (≥30 kg/m2). Number of deployments between baseline and follow-up and initial deployment lengths (in months, using service branch-specific deployment times) were examined. Results: Among the pooled population and specifically Army and Marine Corps service members without obesity, those with longer deployments were significantly less likely to maintain a non-obese BMI than those deploying for shorter lengths. Each additional deployment increased the likelihood of maintaining a non-obese BMI post-deployment for personnel in the Army, Marine Corps, and within the pooled population. Conclusions: Multiple deployments may support healthy weight maintenance; longer deployments may adversely impact weight maintenance. Future research should determine modifiable behaviors related to weight gain post-deployment to inform fitness policies designed to optimize service member readiness and deployability.

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.

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.

Prevalence and predictors of insomnia and sleep medication use in a large tri-service US military sample.

OBJECTIVE: The presence of insomnia in the general military population is not well known. This study aimed to determine the prevalence of probable clinical insomnia and identify factors leading to new-onset insomnia and/or sleep medication use in a large military population. DESIGN: Cross-sectional and longitudinal analyses of a prospective cohort study. PARTICIPANTS: A tri-service US military and veteran cohort (sample range 99,383-137,114). MEASUREMENTS: Participants were surveyed in 2013 (Time 1 [T1]) and 2016 (Time 2 [T2]) using the clinically validated Insomnia Severity Index. The prevalence of insomnia and sleep medication use was quantified at both times. Multivariable models identified military factors associated with new-onset insomnia and/or sleep medication use while adjusting for covariates. RESULTS: The prevalence of insomnia at T1 and T2 was 16.3% and 11.2%, respectively. New-onset insomnia at T2 was reported by 6.0% of participants screening negative at T1; risk factors included Army service, combat deployment experience, and separation from military service. The prevalence of sleep medication use at T1 and T2 was 23.1% and 25.1%, respectively. Sleep medication use at T2 was newly-reported by 17.1% of participants not reporting sleep medication use at T1; risk factors included number of deployments and having a healthcare occupation. CONCLUSIONS: The prevalence of probable clinical insomnia in this large general military population is within the range of previous reports in military and civilian populations. Certain military factors that predict new-onset insomnia and/or sleep medication use should be considered when designing and implementing sleep interventions in military populations.

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.

Longitudinal associations of military-related factors on self-reported sleep among U.S. service members.

STUDY OBJECTIVES: Sleep loss is common in the military, which can negatively affect health and readiness; however, it is largely unknown how sleep varies over a military career. This study sought to examine the relationships between military-related factors and the new onset and reoccurrence of short sleep duration and insomnia symptoms. METHODS: Millennium Cohort Study data were used to track U.S. military service members over time to examine longitudinal changes in sleep. Outcomes were self-reported average sleep duration (categorized as ≤5 h, 6 h, or 7-9 h [recommended]) and/or insomnia symptoms (having trouble falling or staying asleep). Associations between military-related factors and the new onset and reoccurrence of these sleep characteristics were determined, after controlling for multiple health and behavioral factors. RESULTS: Military-related factors consistently associated with an increased risk for new onset and/or reoccurrence of short sleep duration and insomnia symptoms included active duty component, Army or Marine Corps service, combat deployment, and longer than average deployment lengths. Military officers and noncombat deployers had decreased risk for either sleep characteristic. Time-in-service and separation from the military were complex factors; they lowered risk for ≤5 h sleep but increased risk for insomnia symptoms. CONCLUSIONS: Various military-related factors contribute to risk of short sleep duration and/or insomnia symptoms over time, although some factors affect these sleep characteristics differently. Also, even when these sleep characteristics remit, some military personnel have an increased risk of reoccurrence. Efforts to improve sleep prioritization and implement interventions targeting at-risk military populations, behaviors, and other significant factors are warranted.