A dynamical systems analysis of change in PTSD symptoms, depression symptoms, and suicidal ideation among military personnel during treatment for PTSD

OBJECTIVE

The connections among posttraumatic stress disorder (PTSD), depression, and suicidal ideation are elusive because of an overreliance on cross-sectional studies. In this secondary analysis of pooled data from three clinical trials of 742 military personnel, we examined the dynamic relationships among PTSD, depression, and suicidal ideation severity assessed repeatedly during and after outpatient treatment for PTSD.

METHODS

We conducted dynamical systems analyses to explore the potential for coordinated change over time in psychotherapy for PTSD.

RESULTS

Over the course of psychotherapy, PTSD, depression, and suicidal ideation severity changed in coordinated ways, consistent with an interdependent network. Results of eigenvalue decomposition analysis indicated the dominant change dynamic involved high stability and resistance to change but indicators of cycling were also observed, indicating participants "switched" between states that resisted change and states that promoted change. Depression (B = 0.48, SE = 0.11) and suicidal desire (B = 0.15, SE = 0.01) at a given assessment were associated with greater change in PTSD symptom severity at the next assessment. Suicidal desire (B = 0.001, SE < 0.001) at a given assessment was associated with greater change in depression symptom severity at the next assessment. Neither PTSD (B = -0.004, SE = 0.007) nor depression symptom severity (B = 0.000, SE = 0.001) was associated with subsequent change in suicidal ideation severity.

CONCLUSIONS

In a sample of treatment-seeking military personnel with PTSD, change in suicidal ideation and depression may precede change in PTSD symptoms but change in suicidal ideation was not preceded by change in PTSD or depression symptoms.

Impact of handgun ownership and biological sex on startle reactivity to predictable and unpredictable threats

Extant literature suggests that many individuals obtain firearms because they perceive the world as unsafe and believe that firearm ownership increases physical protection. Converging evidence suggests that firearm owners are vulnerable to uncertainty and experience chronic anticipatory anxiety in daily life; however, biological sex is thought to potentially moderate this association. Studies have yet to examine this hypothesis using objective markers of anticipatory anxiety. The present study therefore examined the impact of handgun ownership and biological sex on psychophysiological reactivity to predictable (P-) and unpredictable (U-) threat (N = 133). Male and female adult participants were classified into two groups: a) individuals who do not currently own any handguns (n = 52), and b) individuals who currently own one or more handguns (n = 81). Startle eyeblink potentiation was recorded as an index of aversive reactivity during a well-validated threat-of-shock paradigm designed to probe anticipatory anxiety (during U-threat) and fear (during P-threat). Results revealed no main effect of group on startle reactivity to P- or U-threat. Females displayed greater startle reactivity to threat (P- and U-) compared with males. The main effect was qualified by a significant group x biological sex interaction. Male handgun owners exhibited greater startle to U-threat, but not P-threat, relative to non-handgun owners. There was no effect of group on startle reactivity in females. Findings revealed that biological sex and threat type influenced threat reactivity. Male handgun owners displayed increased sensitivity to stressors that are uncertain, which may reflect an objective mechanism related to firearm ownership.

Impact of the COVID-19 Pandemic on Indicators of Psychological Health and Suicidal Ideation Within an Active Duty U.S. Military Population

INTRODUCTION

The COVID-19 pandemic has had a significant impact on the psychological health of individuals. The pandemic has contributed to increased anxiety, elevated rates of depression, and worsening suicidal ideation among civilians. Reported rates of burnout are also elevated as employees and employers adapted to ever-changing work environments, finding it increasingly difficult to maintain a work-life balance. The objective of this study is to determine how the COVID-19 pandemic impacted the psychological health and rates of suicidal ideation of active duty military personnel in the USA.

MATERIALS AND METHODS

A total of 2055 military personnel and military-adjacent employees stationed at a U.S. Air Force base completed a self-report survey that was administered six times from January 2020 to December 2021. Validated scales assessed measures of psychological health and suicidal ideation. General Estimating Equations were used to examine how indicators of time and psychological health predicted suicidal ideation in a military population.

RESULTS

Life satisfaction, happiness, feeling life is worthwhile, depression severity, and suicidal ideation did not statistically change across the six time points. Worry (P < .01) and depression (P < .001) did decrease significantly, while burnout (P = .01) significantly increased across these time points. Feeling life is worthwhile significantly predicted reduced suicidal ideation (B = -.19; SE = 0.05), while depression (B = 0.11; SE = 0.03), depression severity (B = 0.24; SE = 0.05), worry (B = 0.06; SE = 0.02), and burnout (B = 0.15; SE = 0.07) predicted increased suicidal ideation.

CONCLUSIONS

The rates of depression and worry decreased throughout the pandemic for those in the study while rates of suicidal ideation remained constant, demonstrating the potential resilience of military personnel and military-adjacent employees in response to the COVID-19 pandemic. However, burnout increased and significantly predicted elevated rates of suicidal ideation, highlighting the importance of focusing on reducing workplace stressors for military personnel.

Heightened threat perceptions and reduced stability in anxiety and fear among U.S. adults who carry handguns

Firearm carrying is often motivated to provide safety and is correlated with increased anxiety related to elevated perceptions of the world as a dangerous place. No studies have investigated affective states among firearm owners as they occur in their natural environments. This study used ecological momentary assessment (EMA) to examine cognitive-affective states among firearm owners who carry handguns outside their home (n = 35), firearm owners who do not carry (n = 47), and non-firearm owners (n = 62). Participants completed a self-report questionnaire at baseline followed by EMA surveys of mood state with the Positive and Negative Affect Scale (PANAS) 6 times per day for 28 consecutive days. Carry handgun owners reported significantly higher threat perceptions, measured with the negative cognitions about the world subscale of the shortened Posttraumatic Cognitions Inventory (PTCI), than no-carry handgun owners (Mdiff=2.0, 95% CI=0.8-2.0, d=0.45, p = .001) and non-owners (Mdiff=1.8, 95% CI=0.6-2.9, d=0.42, p = .003). Groups did not significantly differ in mean momentary mood ratings assessed via EMA but stability in high-arousal negative arousal was significantly reduced among carry handgun owners (F(2, 150)= 3.7, p = .026). Results suggest firearm owners who carry handguns view the world as especially dangerous, are more likely to experience shifts in anxiety and fear, and take longer to recover from periods of elevated anxiety and fear.

Temporal-dimensional examination of the Scale for Suicidal Ideation in a cohort of service members in treatment for PTSD

OBJECTIVE

Failing to account for temporal dynamics can hinder our understanding of suicidal ideation and the potential mechanisms underlying increased risk for suicide death and suicide attempts associated with posttraumatic stress disorder (PTSD). To address these limitations, this study used an analytic approach based on Dynamical Systems Theory to describe temporal patterns associated with multiple dimensions of suicidal ideation in a treatment-seeking sample of military personnel diagnosed with PTSD.

METHOD

We performed a secondary analysis of archived data from 742 active-duty military personnel (90% male, 57% white, mean age = 33 ± 7.4 years) enrolled in three clinical trials to examine the dimensional measurement properties of the first 5 items of the Scale for Suicidal Ideation (SSI).

RESULTS

Findings indicated two change dynamics for suicidal ideation: homeostatic (i.e., the tendency for suicidal ideation to return to a stable point) and cyclical (i.e., the tendency for suicidal ideation to switch back and forth between higher and lower values). Cycling was the dominant dynamic and was related to variables other from suicidal ideation.

CONCLUSION

The cyclic nature of suicidal ideation suggests that assessment timing and context could influence observed associations with other variables. Analytic approaches and clinical methods that do not account for the temporal dynamics of suicide risk could miss these properties, thereby hindering efforts to identify mechanisms underlying the relationship between PTSD and suicidal thoughts and behaviors and limiting opportunities for proactive and timely intervention. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Identifying suicidal subtypes and dynamic indicators of increasing and decreasing suicide risk in active duty military personnel: Study protocol

Objectives

Several recent studies have demonstrated that posttraumatic stress disorder (PTSD) and insomnia treatments are associated with significant reductions in suicidal ideation (SI) among service members. However, few investigations have evaluated the manner in which suicide risk changes over time among military personnel receiving PTSD or insomnia treatments. This paper describes the study protocol for a project with these aims: (1) explore potential genetic, clinical, and demographic subtypes of suicide risk in a large cohort of deployed service members; (2) explore subtype change in SI as a result of evidence-based psychotherapies for PTSD and insomnia; (3) evaluate the speed of change in suicide risk; and (4) identify predictors of higher- and lower-risk for suicide.

Methods

Active duty military personnel were recruited for four clinical trials (three for PTSD treatment and one for insomnia treatment) and a large prospective epidemiological study of deployed service members, all conducted through the South Texas Research Organizational Network Guiding Studies on Trauma and Resilience (STRONG STAR Consortium). Participants completed similar measures of demographic and clinical characteristics and subsets provided blood samples for genetic testing. The primary measures that we will analyze are the Beck Scale for Suicide Ideation, Beck Depression Inventory, and the PTSD Checklist for DSM-IV.

Discussion

Results from this study will offer new insights into the presence of discrete subtypes of suicide risk among active duty personnel, changes in risk over time among those subtypes, and predictors of subtypes. Findings will inform treatment development for military service members at risk for suicide.

A dynamical systems approach to examining the efficacy of suicide-focused interventions

OBJECTIVE

Suicide risk is a nonlinear temporal process, but the ways in which suicide-focused interventions have statistically examined risk effects have ignored these nonlinearities. This paper highlights the potential benefits of using data analytic methods that account for nonlinear change patterns.

METHOD

Using a dynamical systems perspective, interventions are framed in terms of attractor dynamics. An attractor has three primary qualities where an intervention can have an effect. These correspond to contextual differences, shifts in the underlying temporal patterns, and changes in the stability of the temporal pattern.

RESULTS/CONCLUSIONS

It is argued that the ideal effect is one in which there is both an observed change in stability and a shift in the underlying temporal pattern toward less risk. Other types of intervention effects can have alternate explanations that are less desirable. Mean, variance, and growth differences are discussed within a systems context, and an example model is provided using Latent Change Score Modeling (McArdle, Annual Review of Psychology, 60, 2009, 577-605).

Mokken Scale Analysis of Lifetime Responses on the Columbia Suicide Severity Rating Scale's Severity of Ideation Subscale

Suicide risk screening assumes that suicidal thoughts and behaviors exist on a continuous, hierarchical spectrum with some suicidal thoughts implicated with greater risk for suicidal behaviors. However, screening measures based on the hierarchical model may not capture the suicide risk construct. This study assessed psychometric properties of the Columbia Suicide Severity Rating Scale (CSSRS) for (a) between- and within-person measurement dimensions, (b) item utility in capturing the suicide risk construct, and (c) tenability of a hierarchical risk model. We found that the CSSRS functions differentially between and within individuals, CSSRS items capture more suicide risk construct, and that CSSRS items in current practice likely appear in the correct order. The current CSSRS reasonably represents within-person suicide risk, but not between-person risk. Scale norms or alternate scoring could facilitate functional equivalence and utility for between- and within-person CSSRS dimensions.

The role of depression and suicidal cognitions as contributors to suicide risk among active duty soldiers reporting symptoms of posttraumatic stress disorder

BACKGROUND

Military suicide rates have risen across all service branches, with the overall rate surpassing that of the general population for the first time in history in 2008. Service members with posttraumatic stress disorder (PTSD) are at a substantially higher risk for suicidal ideation, suicide attempts, and death by suicide than their peers without PTSD. While the link between PTSD and suicide is well established in the literature, less is known about the precise nature of that connection. Several constructs have been implicated as potential mediators of this relation, such as depression, alcohol use, suicidal cognitions, and sleep disturbance. Yet, to our knowledge, these constructs have never been examined simultaneously in a single model to determine mediational influence for suicide risk among soldiers with PTSD.

METHODS

A sample of 172 active duty Army soldiers completed a series of measures targeting the aforementioned constructs. Data were analyzed using mediation model analyses.

RESULTS

Suicidal cognitions fully mediated the relation between PTSD symptoms and current suicide risk severity. The indirect effect for suicidal cognitions was significantly larger than indirect effects for alcohol use, depression, and sleep disturbance. Exploratory analyses suggest serial mediation of the relation between PTSD and current suicide risk by depression and suicidal cognitions.

LIMITATIONS

These results should be interpreted within the context of study limitations, to include use of self-report data and inability to firmly establish temporal sequencing assumed in mediation.

CONCLUSIONS

Implications of this study include the improvement of suicide risk assessment and individualized treatment planning for suicidal military personnel with PTSD.

Temporal trends in new exposure to antiepileptic drug monotherapy and suicide-related behavior

OBJECTIVE

Because some recent studies suggest increased risk for suicide-related behavior (SRB; ideation, attempts) among those receiving antiepileptic drugs (AEDs), we examined the temporal relationship between new AED exposure and SRB in a cohort of older veterans.

METHODS

We used national Veterans Health Administration databases to identify veterans aged ≥65 years who received a new AED prescription in 2004-2006. All instances of SRB were identified using ICD-9-CM codes 1 year before and after the AED exposure (index) date. We also identified comorbid conditions and medication associated with SRB in prior research. We used generalized estimating equations with a logit link to examine the association between new AED exposure and SRB during 30-day intervals during the year before and after the index date, controlling for potential confounders.

RESULTS

In this cohort of 90,263 older veterans, the likelihood of SRB the month prior to AED exposure was significantly higher than in other time periods even after adjusting for potential confounders. Although there were 87 SRB events (74 individuals) the year before and 106 SRB events (92 individuals) after, approximately 22% (n = 16) of those also had SRB before the index date. Moreover, the rate of SRB after AED start was gradually reduced over time.

CONCLUSIONS

The temporal pattern of AED exposure and SRB suggests that, in clinical practice, the peak in SRB is prior to exposure. While speculative, the rate of gradual reduction in SRB thereafter suggests that symptoms may prompt AED prescription.

Antiepileptic drug monotherapy exposure and suicide-related behavior in older veterans

OBJECTIVES

To examine the association between antiepileptic drug (AED) receipt and suicide-related behavior (SRB) in older veterans.

DESIGN

Retrospective database analysis.

SETTING

Veterans Health Administration (VHA) inpatient and outpatient care.

PARTICIPANTS

Veterans aged 65 and older in 2004 to 2006.

MEASUREMENTS

SRB was identified using International Classification of Diseases, Ninth Revision, Clinical Modification codes, and new AED monotherapy was identified using the VHA product variable in pharmacy data. Comorbid conditions and medications were also identified as potential confounders using previously validated algorithms. Cox proportional hazards models controlling for the propensity to receive AEDs examined the association between any AED exposure, specific AEDs, and time to SRB.

RESULTS

Within the eligible sample of 2.15 million individuals, 332 cases of SRB were found. Overall, 98% of participants were male, and 67% were non-Hispanic white. Affective disorders and severe psychiatric conditions were strongly associated with SRB and were included in the propensity score. AED exposure displayed a significant association with SRB (odds ratio = 4.10, 95% confidence interval (CI) = 3.85-6.63) after adjusting for propensity to receive AEDs. Stratified analyses found similar results for those with (hazard ratio (HR) = 4.00, 95% CI = 2.9-5.5) and without (HR = 4.57, 95% CI = 1.15-18.20) mental health comorbidities. Gabapentin, phenytoin, lamotrigine, levetiracetam, topiramate, and valproate were significantly associated with SRB.

CONCLUSION

Exposure to five common AEDs was associated with SRB in older VHA beneficiaries. Given the strong associations between psychiatric comorbidity and SRB, clinicians treating elderly adults should weigh this potential adverse effect into their consideration for treatment of those receiving AEDs. Particular attention should be given to depression and suicidality screening in people prescribed AEDs.