Polygenic risk for suicide attempt is associated with lifetime suicide attempt in US soldiers independent of parental risk

BACKGROUND

Suicide is a leading cause of death worldwide. Whereas some studies have suggested that a direct measure of common genetic liability for suicide attempts (SA), captured by a polygenic risk score for SA (SA-PRS), explains risk independent of parental history, further confirmation would be useful. Even more unsettled is the extent to which SA-PRS is associated with lifetime non-suicidal self-injury (NSSI).

METHODS

We used summary statistics from the largest available GWAS study of SA to generate SA-PRS for two non-overlapping cohorts of soldiers of European ancestry. These were tested in multivariable models that included parental major depressive disorder (MDD) and parental SA.

RESULTS

In the first cohort, 417 (6.3 %) of 6573 soldiers reported lifetime SA and 1195 (18.2 %) reported lifetime NSSI. In a multivariable model that included parental history of MDD and parental history of SA, SA-PRS remained significantly associated with lifetime SA [aOR = 1.26, 95%CI:1.13-1.39, p < 0.001] per standardized unit SA-PRS]. In the second cohort, 204 (4.2 %) of 4900 soldiers reported lifetime SA, and 299 (6.1 %) reported lifetime NSSI. In a multivariable model that included parental history of MDD and parental history of SA, SA-PRS remained significantly associated with lifetime SA [aOR = 1.20, 95%CI:1.04-1.38, p = 0.014]. A combined analysis of both cohorts yielded similar results. In neither cohort or in the combined analysis was SA-PRS significantly associated with NSSI.

CONCLUSIONS

PRS for SA conveys information about likelihood of lifetime SA (but not NSSI, demonstrating specificity), independent of self-reported parental history of MDD and parental history of SA.

LIMITATIONS

At present, the magnitude of effects is small and would not be immediately useful for clinical decision-making or risk-stratified prevention initiatives, but this may be expected to improve with further iterations. Also critical will be the extension of these findings to more diverse populations.

Suicide Behavior Results From the U.S. Army's Suicide Prevention Leadership Tool Study: The Behavioral Health Readiness and Suicide Risk Reduction Review (R4)

INTRODUCTION

The U.S. Army developed a new tool called the Behavioral Health Readiness and Suicide Risk Reduction Review (R4) for suicide prevention. A 12-month evaluation study with the primary objective of testing the hypothesis (H1) that Army units receiving R4 would demonstrate improved outcomes in suicidal-behavior measures following the intervention, relative to control, was then conducted. The results of analyses to answer H1 are herein presented.

MATERIALS AND METHODS

The R4 intervention (R4-tools/instructions/orientation) evaluation study, Institutional Review Board approved and conducted in May 2019-June 2020, drew samples from two U.S. Army divisions and employed a repeated measurement in pre-/post-quasi-experimental design, including a nonequivalent, but comparable, business-as-usual control. Intervention effectiveness was evaluated using self-report responses to suicide-related measures (Suicide Behaviors Questionnaire-Revised/total-suicide behaviors/ideations/plans/attempts/non-suicidal self-injuries) at 6-/12-month intervals. Analyses examined baseline to follow-up linked and cross-sectional cohorts, incidence/prevalence, and intervention higher-/lower-use R4 subanalyses.

RESULTS

Both divisions demonstrated favorable in-study reductions in total-suicide burden, with relatively equivalent trends for total-suicide behaviors, total-suicide risk (Suicide Behaviors Questionnaire-Revised), suicidal ideations, and non-suicidal self-injuries. Although both demonstrated reductions in suicide plans, the control showed a more robust trend. Neither division demonstrated a significant reduction in suicide attempts, but subgroup analyses showed a significant reduction in pre-coronavirus disease 2019-attempt incidence among those with higher-use R4 relative to control.

CONCLUSIONS

There is no evidence of harm associated with the R4 intervention. R4 effectiveness as a function of R4 itself requires confirmatory study. R4 is judged an improvement (no evidence of harm + weak evidence of effectiveness) over the status quo (no safety data or effectiveness studies) with regard to tool-based decision-making support for suicide prevention in the U.S. Army.

Polygenic risk for major depression is associated with lifetime suicide attempt in US soldiers independent of personal and parental history of major depression

Suicide is a major public health problem. The contribution of common genetic variants for major depressive disorder (MDD) independent of personal and parental history of MDD has not been established. Polygenic risk score (using PRS-CS) for MDD was calculated for US Army soldiers of European ancestry. Associations between polygenic risk for MDD and lifetime suicide attempt (SA) were tested in models that also included parental or personal history of MDD. Models were adjusted for age, sex, tranche (where applicable), and 10 principal components reflecting ancestry. In the first cohort, 417 (6.3%) of 6,573 soldiers reported a lifetime history of SA. In a multivariable model that included personal [OR = 3.83, 95% CI:3.09-4.75] and parental history of MDD [OR = 1.43, 95% CI:1.13-1.82 for one parent and OR = 1.64, 95% CI:1.20-2.26 for both parents), MDD PRS was significantly associated with SA (OR = 1.22 [95% CI:1.10-1.36]). In the second cohort, 204 (4.2%) of 4,900 soldiers reported a lifetime history of SA. In a multivariable model that included personal [OR = 3.82, 95% CI:2.77-5.26] and parental history of MDD [OR = 1.42, 95% CI:0.996-2.03 for one parent and OR = 2.21, 95% CI:1.33-3.69 for both parents) MDD PRS continued to be associated (at p = .0601) with SA (OR = 1.15 [95% CI:0.994-1.33]). A soldier's PRS for MDD conveys information about likelihood of a lifetime SA beyond that conveyed by two predictors readily obtainable by interview: personal or parental history of MDD. Results remain to be extended to prospective prediction of incident SA. These findings portend a role for PRS in risk stratification for suicide attempts.

Far Forward Behavioral Health Service Delivery in Future Combat Environments: A Qualitative Needs Assessment

INTRODUCTION

It is expected that future multi-domain operational (MDO) combat environments will be characterized by limited capabilities for immediate combat stress control support services for soldiers or immediate evacuation from theater. The operational requirements of the future battlefield make it unlikely that current models for behavioral health (BH) treatment could be implemented without significant adjustments. We conducted a qualitative study with Special Forces medics and operators and soldiers who had deployed to austere conditions in small groups in an effort to inform construction of a BH service delivery model for an MDO environment. The objectives of this study were (1) characterizing stressors and BH issues that were encountered and (2) describing mitigation strategies and resources that were useful or needed in these types of deployments.

MATERIALS AND METHODS

Six focus groups were conducted at three army installations with 23 active duty soldiers, including three groups of medics using a semi-structured interview guide focused on stressors they encountered during deployments to austere conditions, and the impact of those stressors on mission and focus. Focus group recordings were transcribed, imported into NVivo software (version 12), and independently coded by two researchers. An analysis was then conducted to develop themes across participants. The study was reviewed by the Walter Reed Army Institute of Research Human Subjects Protection Board.

RESULTS

Behavioral health concerns were commonly cited as a stressor in far forward environments. Other common stressors included ineffective or inexperienced leaders, as well as poor team dynamics (e.g., communication and cohesion). Four primary strategies were mentioned as mitigations for deployment stressors: leadership, morale, resilience training, and strength of the team. When asked about resources or training that would have helped with these types of deployments, participants frequently mentioned the availability of BH providers and development of new and realistic BH skills trainings for non-providers and leaders.

CONCLUSIONS

Current models for treating BH problems need to be adapted for the future MDO environments in which soldiers will be expected to deploy. Understanding what issues need to be addressed in these environments and how they can best be delivered is an important first step. This study is the first to use qualitative results from those who have already deployed to such environments to describe the stressors and BH issues that were most commonly encountered, the mitigation strategies used, and the resources that were useful or needed.

Methodology of the U.S. Army's Suicide Prevention Leadership Tool Study: The Behavioral Health Readiness and Suicide Risk Reduction Review (R4)

INTRODUCTION

The Secretary of the U.S. Army issued two directives in late 2017 to directly combat the problem of suicide in the U.S. Army. The first was to develop an Army tool to assist commanders and first-line leaders in preventing suicide and improving behavioral health (BH) outcomes, which has been previously published as the BH Readiness and Risk Reduction Review (R4). The second was to conduct an evaluation study of the tool with Army units in the field. This study is the first to empirically examine the Army's tool-based methods for identifying and caring for the health and welfare of soldiers at risk for suicide, and this article outlines the methodology employed to study the effectiveness of the R4 tools and accomplish the Secretary's second directive.

METHODS

The Walter Reed Army Institute of Research Institutional Review Board approved the R4 study. The study employed a repeated measurements in pre/post quasi-experimental design, including a nonequivalent but comparable business-as-usual control group. The R4 intervention consisted of the R4 tools, accompanying instructions, and an orientation. Samples were drawn from two geographically separated U.S. Army divisions in the continental United States, each composed of four comparable brigades. Study implementation consisted of three phases and three data collections over the course of 12 months. Soldiers completed anonymous survey instruments to assess a range of health factors, behaviors, characteristics, tool-related decision-making processes, and the frequency, type, and quality of interactions between soldiers and leaders.

RESULTS

The R4 study commenced on May 6, 2019, and concluded on June 4, 2020. Sample size goals were achieved for both the divisions at all three data collection time points.

CONCLUSIONS

The methodology of the R4 study is critical for the U.S. Army from both a precedential and an outcome-based standpoint. Despite the use of many previous tools and programs for suicide prevention, this is the first time the Army has been able to empirically test the effectiveness of tool-supported decision-making among Army units in a rigorous fashion. The methodology of such a test is a critical marker for future interventional inquiries on the subject of suicide in the Army, and the results will allow for more informed decision-making by leaders when approaching these ongoing challenges.

Results of the Behavioral Health Readiness Evaluation and Decision-Making Instrument Study

INTRODUCTION

Recent reports have demonstrated behavioral health (BH) system and individual provider challenges to BH readiness success. These pose a risk to winning on the battlefield and present a significant safety issue for the Army. One of the most promising areas for achieving better BH readiness results lies in improving readiness decision-making support for BH providers. The Walter Reed Army Institute of Research (WRAIR) has taken the lead in addressing this challenge by developing and empirically testing such tools. The results of the Behavioral Health Readiness Evaluation and Decision-Making Instrument (B-REDI) field study are herein described.

METHODS

The B-REDI study received WRAIR Institutional Review Board approval, and BH providers across five U.S. Army Forces Command installations completed surveys from September 2018 to March 2019. The B-REDI tools/training were disseminated to 307 providers through random clinic assignments. Of these, 250 (81%) providers consented to participate and 149 (60%) completed both initial and 3-month follow-up surveys. Survey items included a wide range of satisfaction, utilization, and proficiency-level outcome measures. Analyses included examinations of descriptive statistics, McNemar's tests pre-/post-B-REDI exposure, Z-tests with subgroup populations, and chi-square tests with demographic comparisons.

RESULTS

The B-REDI resulted in broad, statistically significant improvements across the measured range of provider proficiency-level outcomes. Net gains in each domain ranged from 16.5% to 22.9% for knowledge/awareness (P = .000), from 11.1% to 15.8% for personal confidence (P = .001-.000), and from 6.2% to 15.1% for decision-making/documentation (P = .035-.002) 3 months following B-REDI initiation, and only one (knowledge) failed to maintain a statistically significant improvement in all of its subcategories. The B-REDI also received high favorability ratings (79%-97% positive) across a wide array of end-user satisfaction measures.

CONCLUSIONS

The B-REDI directly addresses several critical Army BH readiness challenges by providing tangible decision-making support solutions for BH providers. Providers reported high degrees of end-user B-REDI satisfaction and significant improvements in all measured provider proficiency-level domains. By effectively addressing the readiness decision-making challenges Army BH providers encounter, B-REDI provides the Army BH health care system with a successful blueprint to set the conditions necessary for providers to make more accurate and timely readiness determinations. This may ultimately reduce safety and mission failure risks enterprise-wide, and policymakers should consider formalizing and integrating the B-REDI model into current Army BH practice.

Military suicide prevention: The importance of leadership behaviors as an upstream suicide prevention target

OBJECTIVE

To evaluate the longitudinal relationships between unit cohesion, Army leader behaviors, and subordinate suicidal/death ideation. Recent cross-sectional research indicates that subordinates who perceive that their leaders instill a sense of purpose regarding military service demonstrate less frequent suicidal ideation.

METHOD

Five hundred fifty-nine soldiers completed self-report measures of perceptions of leadership behaviors, unit cohesion, and suicidal/death ideation during deployment as well as one and three months following deployment. Latent change score modeling was conducted to evaluate the course and direction of study variables as well as the relationship between them.

RESULTS

Although lower levels of suicidal/death ideation were related to leader-provided purpose, leader-provided meaning, and unit cohesion at baseline, only leader-provided purpose and unit cohesion prospectively predicted changes in suicidal/death ideation.

CONCLUSIONS

Consistent with the goal of military leadership to augment effective clinical interventions that reduce suicide risk, prevention programs that reach a broader population of personnel should be considered. Enhanced leadership training may be an important primary prevention tool to reduce suicide risk that warrants further research.