Severity and Symptom Trajectory in Combat-Related PTSD: a Review of the Literature

Distressing memories: A continuum from wellness to PTSD

BACKGROUND

Exposure to traumatic events is a frequent source of distress, provoking isolated symptoms such as distressing memories (DM) to full-blown post-traumatic stress disorder (PTSD). We aimed to assess the continuum theory using DM as an isolated symptom, and to examine trauma consequences in a exposed to traumatic events.

METHODS

Using data from the National Epidemiologic Study of Alcohol and Related Conditions III, we assessed the prevalence of DM in a trauma exposed sample, and examined their sociodemographic and lifetime psychiatric correlates, comparing three groups: (i) controls (no DM, no PTSD); (ii) participants with isolated DM without PTSD; (iii) participants with PTSD. We estimated the sensitivity and specificity of DM for PTSD diagnosis.

RESULTS

In our sample of 17,505 participants exposed to trauma, 13 % had PTSD and 42 % had DM without PTSD. The sensitivity of DM for the diagnosis of PTSD was 95.14 %, specificity was 51.91 %. Participants with DM and those with PTSD shared the same socio-demographic correlates. Participants with DM reported more lifetime psychiatric disorders (mood disorders - mainly depressive disorders and bipolar type 1 disorder; anxiety disorders - mainly social anxiety disorder, substance use disorders - mainly opioid use disorder and cannabis disorder; eating disorders - mainly binge eating disorder; personality disorders - mainly borderline personality disorder- and suicidality) than controls, but less than participants with PTSD.

CONCLUSION

DM represent an intermediate state between well-being and post-traumatic stress disorder; DM is also associated with other psychiatric disorders. It should be considered as a transdiagnostic psychiatric symptom useful for clinicians in identifying psychiatric vulnerability.

The impact of moral injury on trajectories of depression: a five-year longitudinal study among recently discharged Israeli veterans

BACKGROUND

Perpetrating or witnessing acts that violate one's moral code are frequent among military personnel and active combatants. These events, termed potentially morally injurious events (PMIEs), were found to be associated with an increased risk of depression, in cross-sectional studies. However, the longitudinal contribution of PMIEs to depression among combatants remains unclear.

METHOD

Participants were 374 active-duty combatants who participated in a longitudinal study with four measurement points: T1-one year before enlistment, T2-at discharge from army service, and then again 6- and 12-months following discharge (T3 and T4, respectively). At T1, personal characteristics assessed through semi-structured interviews. At T2-T4, PMIEs and depressive symptoms were assessed.

RESULTS

At discharge (T2), a total of 48.7% of combatants reported experiencing PMIEs incident, compared with 42.4% at T3 and 30.7% at T4. We found a significant interaction effect in which combatants endorsing PMIEs at discharge reported higher severity of depression symptoms at discharge (T2) than combatants who reported no PMIEs. This effect decreased over time as depression levels were lower at T3 and T4.

CONCLUSIONS

PMIE experiences, and especially PMIE-Betrayal experiences, were found to be valid predictors of higher severity of depression symptoms after the first year following discharge.

Risk for PTSD symptom worsening during new PTSD treatment episode in a nationally representative sample of treatment-seeking U.S. veterans with subthreshold PTSD

Previous research has examined risk factors associated with poorer treatment outcomes for military Veterans with PTSD. However, work has not examined risk for symptom worsening among Veterans with subthreshold PTSD. The aim of this study was to examine demographic, psychiatric, physical health, and pre-treatment PTSD symptom clusters associated with clinically significant worsening of PTSD among a nationally representative sample of United States (U.S.) Veterans with subthreshold PTSD. Participants were Veterans (weighted N = 3162; unweighted N = 236) with subthreshold PTSD entering a new episode of treatment at U.S. Veterans Affairs PTSD specialty clinics during fiscal years 2018 and 2019. Data was collected as part of the Veterans Outcome Assessment, a yearly baseline and 3-month follow-up telephone survey. Analyses used weighted calculations to support the use of VOA data to draw inferences about all eligible Veterans, and binary logistic regression was used to examine risk factors for symptom worsening. Over 1/3 (37.7%) of Veterans with subthreshold PTSD experienced clinically significant symptom worsening from baseline to follow-up. Adjusted analyses revealed several risk factors for symptom worsening, including demographic (e.g., male sex, White race), psychiatric (personality and anxiety disorders), health care utilization (e.g., more primary care encounters in the previous year), physical health disability, and specific baseline PTSD symptom clusters (negative affect and anxious arousal). Findings suggest that Veterans with subthreshold symptoms seeking treatment for PTSD are at risk for symptom worsening, and highlight the importance of assessment, prevention, and treatment in targeting veterans with PTSD symptoms below the diagnostic threshold.

The impact of neurotoxicant exposures on posttraumatic stress disorder trajectories: The Ft. Devens Gulf War Veterans Cohort

Gulf War veterans (GWVs) were exposed to neurotoxicants, including sarin nerve gas, anti-nerve agent pills, pesticides, oil well fires, and fumes from unvented tent heaters, all of which have been associated with subsequent adverse health. Posttraumatic stress disorder (PTSD) symptoms have also been associated with GW deployment; however, associations between exposures and PTSD symptoms have not been investigated. We assessed PTSD symptom trajectories and associations with neurotoxicant exposures in Ft. Devens Cohort (FDC) veterans (N = 259) who endorsed trauma exposure during deployment and completed the PTSD Checklist at three follow-ups (1992-1993, 1997-1998, 2013-2017). Results indicate that among veterans with more severe initial PTSD symptoms, symptoms remained significantly higher across follow-ups, Bs = -1.489-1.028, whereas among those with low initial PTSD symptoms, symptom severity increased significantly over time, Bs = 1.043-10.304. Additionally, neurotoxicant exposure was associated with a significant increase in PTSD symptoms, Bs = -1.870-9.003. Significant interactions between time and exposures were observed for PTSD symptom clusters, suggesting that among participants with high initial PTSD symptom, unexposed veterans experienced symptom alleviation, whereas exposed veterans' PTSD symptoms remained high. In GWVs with low initial PTSD symptoms, both unexposed and exposed veterans experienced PTSD symptom exacerbations over time; however, this occurred at a faster rate among exposed veterans. These findings suggest that in the years following deployment, GWVs who were exposed to both traumatic events and neurotoxicants may experience more severe and chronic PTSD symptoms than those without neurotoxicant exposures.

Changes in Trauma-Related Cognitions and Emotions After Eliciting Moral Elevation: Examining the Effects of Viewing Others' Virtuous Behavior on Veterans with PTSD

Moral elevation is described as feeling inspired after witnessing someone perform a virtuous act. Past work suggests the features of moral elevation may be contrary to PTSD, yet few studies have directly tested its impact on relevant symptoms. This experimental study assessed changes in trauma-related cognitions and emotions from after a trauma reminder task to after an elevation induction exercise. We hypothesized that higher elevation after the induction exercise would be associated with greater reductions in cognitions and emotions. Veterans with probable PTSD (N = 38) completed measures of trauma-related cognitions and emotions, once after a written trauma narrative exercise (T1) and again after watching two videos designed to elicit elevation (T2). Veterans also completed measures of state elevation after each video. Results suggest veterans experienced small, significant decreases in self-blame (d = 0.36) and negative beliefs about others (d = 0.46), and medium, significant decreases in guilt (d = 0.68), shame (d = 0.60), and negative beliefs about self (d = 0.69) between T1 and T2. As hypothesized, higher elevation was associated with significantly greater reductions in multiple outcomes above and beyond the effects of general positive affect. Specifically, there were medium effects for changes in shame (β = -0.42, SE = 0.17, p = .019, Δf ² = 0.25), negative view of others (β = -0.34, SE = 0.16, p = .044, Δf ² = 0.20), and a large effect for changes in negative view of self (β = -0.31, SE = 0.13, p = .019, Δf ² = 0.54). These findings suggest elevation may be well-suited to target trauma-related symptoms and future research should further examine its clinical utility.

The role of inhibitory processes in the relationship between subsyndromal PTSD symptoms and aggressive behaviour

The issue of aggressive behaviours among military populations is important for a number of reasons, including the potential associated occupational, social and functional impacts. Controlled aggressive behaviour is an adaptive requirement of some military roles, however, this aggression can become maladaptive when uncontrolled, or contextually inappropriate. Elevated aggression among deployed veterans has been identified in a number of studies, although the reasons for it are not well understood. Deployed populations have elevated levels of stress and trauma exposure, have higher rates of childhood and other lifetime trauma exposures and have a heightened risk for subsyndromal or full PTSD. Both trauma exposure and PTSD have been found to be associated with executive function deficits, and increased anger and aggressive behaviours. The purpose of this paper was to explore the contribution of both early PTSD symptoms and cognitive disinhibition in predicting increased aggressive behaviour following deployment in a healthy active serving cohort. After controlling for pre-deployment PTSD symptoms and cognitive function, there were significant main effects of both PTSD symptoms and cognitive function on increased aggression at post-deployment. Furthermore, the positive association between PTSD symptoms and post-deployment aggression was moderated by response inhibition deficits in the domains of false positive errors as well as faster reaction times. Subsidiary analyses showed that the effects of increased reaction time in particular increased the likelihood of PTSD symptoms being coupled with increased aggression. These findings highlight the potential effects of repeated occupational stress exposure and point to possible cognitive adaptations and long-term risk for disorder.

Amygdalar endocannabinoids are affected by predator odor stress in a sex-specific manner and modulate acoustic startle reactivity in female rats

Understanding sex differences in behavioral and molecular effects of stress has important implications for understanding the vulnerability to chronic psychiatric disorders associated with stress response circuitry. The amygdala is critical for emotional learning and generating behavioral responses to stressful stimuli, and preclinical studies indicate that amygdalar endocannabinoid (eCB) signaling regulates emotional states. This study measured eCB contents in the basolateral (BLA) and central (CeA) amygdala of male and female rats exposed to predator odor stress (bobcat urine) and tested for contextual avoidance 24 h later. Stressed females had lower levels of 2-arachidonoyl glycerol (2-AG) in the BLA and higher levels of anandamide (AEA) in the CeA, while exposure to bobcat urine did not affect amygdalar eCB contents in males. We previously reported that female rats exposed to bobcat urine exhibit blunted acoustic startle reactivity (ASR) 48 h after predator odor stress. Therefore, we tested the hypothesis that intra-BLA injection of a diacylglycerol lipase (DAGL) inhibitor (which would be expected to reduce 2-AG levels in BLA) and intra-CeA injection of a fatty acid amide hydrolase (FAAH) inhibitor (which would be expected to increase AEA levels in CeA) would mimic previously observed predator odor stress-induced reductions in ASR. Contrary to our hypothesis, microinjections of either the DAGL inhibitor DO34 into the BLA or the FAAH inhibitor URB597 into the CeA significantly increased ASR in females compared to vehicle-treated rats. These findings describe sex-specific effects of predator odor stress on amygdalar eCBs, and new roles for amygdalar eCBs in regulating behavior in females.

The Mediation Effect of Hyperarousal Symptoms on the Relationship Between Childhood Physical Abuse and Suicidal Ideation of Patients With PTSD

Objective: This study examined the relationship of childhood physical abuse, posttraumatic stress disorder (PTSD), depression, and suicide in patients with PTSD through path analysis. Materials and Methods: A total of 114 patients with PTSD (36 men and 78 women) were recruited and completed psychological assessments including the Childhood Trauma Questionnaire, the scale for suicidal ideation, the clinician-administered PTSD scale for the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, the PTSD checklist, and the Hospital Anxiety and Depression Scale. Structural equation modeling was used to evaluate the results. We developed a model including childhood physical abuse experience as the causal variable, suicidal ideation as a result variable, and PTSD and depression as mediation variables. PTSD symptoms were divided into four clusters [intrusion, avoidance, negative cognition and mood, and altered arousal and reactivity (hyperarousal)] to determine predictive power for suicide. Results: PTSD symptoms fully mediated the relationship between childhood physical abuse and suicidal ideation. Furthermore, PTSD symptoms fully mediated the relationship between childhood physical abuse and depression. Among the PTSD symptoms, hyperarousal was the only symptom cluster that mediated the relationship between childhood physical abuse and suicidal ideation. The symptom clusters of negative cognition and mood as well as hyperarousal mediated the relationship between childhood physical abuse and depression. Conclusions: This study presents a link between childhood physical abuse and current symptoms in patients with PTSD, and highlights specific PTSD symptom clusters (i.e., hyperarousal, negative cognition and mood) that may increase the risk for psychopathology later in life.

Randomized Controlled Trial of Riluzole Augmentation for Posttraumatic Stress Disorder: Efficacy of a Glutamatergic Modulator for Antidepressant-Resistant Symptoms

OBJECTIVE

Current pharmacologic treatments for posttraumatic stress disorder (PTSD) have shown limited efficacy, prompting a call to investigate new classes of medications. The current study investigated the efficacy of glutamate modulation with riluzole augmentation for combat-related PTSD symptoms resistant to treatment with selective serotonin reuptake inhibitors (SSRIs) or serotonin-norepinephrine reuptake inhibitors (SNRIs).

METHODS

A randomized, double-blind, placebo-controlled, parallel trial was conducted at Walter Reed National Military Medical Center and Syracuse VA Medical Center between December 2013 and November 2017. Veterans and active duty service members with combat-related PTSD (per the Clinician Administered PTSD Scale [CAPS]) who were not responsive to SSRI or SNRI pharmacotherapy were randomized to 8-week augmentation with a starting dose of 100 mg/d of riluzole (n = 36) or placebo (n = 38) and assessed weekly for PTSD symptoms, anxiety, depression, disability, and side effects.

RESULTS

Intent-to-treat analyses (N = 74) of the primary outcome (CAPS for DSM-IV) showed no significant between-group difference in change in overall PTSD symptoms (F = 0.64, P = .422), with a small effect size (d = 0.25). There was clinically significant within-group improvement in overall PTSD symptoms in both groups, with a greater mean (SD) decrease in CAPS score in the riluzole group (-21.1 [18.9]) than in the placebo group (-16.7 [17.2]). Exploratory analyses of PTSD symptom clusters showed significantly greater improvement on hyperarousal symptoms in the riluzole group as measured by the PTSD Checklist-Specific-Subscale D (d = 0.48) and near-significant findings on the CAPS Subscale D. Riluzole augmentation was not superior to placebo on change in depression, anxiety, or disability severity.

CONCLUSIONS

Although preliminary, the exploratory findings of this study offer some evidence that riluzole augmentation of an SSRI or SNRI may selectively improve PTSD hyperarousal symptoms without changes in overall PTSD symptoms, depression, anxiety, or disability. Additional investigation of the mechanism of the efficacy of riluzole for hyperarousal symptoms is warranted.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT02155829.

The 20-year course of posttraumatic stress disorder symptoms among veterans

Although numerous longitudinal studies have examined heterogeneity in posttraumatic stress disorder (PTSD) symptom course, the long-term course of the disorder remains poorly understood. This study sought to understand and predict long-term PTSD symptom course among a nationwide sample of Operations Enduring Freedom and Iraqi Freedom veterans enrolled in Veterans Health Administration services. We assessed PTSD symptoms at 4 time points over approximately 4.5 years (M = 55.11 months, SD = 6.89). Participants (N = 1,353) with and without probable PTSD were sampled at a 3:1 ratio, and male and female veterans were sampled at a 1:1 ratio to fully explore the heterogeneity of PTSD symptom course and the effect of sex on symptom course. By coding time as years since index trauma, we estimated the course of PTSD symptoms over 20 years. Results indicate symptom course is most appropriately characterized by substantial heterogeneity. On average, veterans experienced initial PTSD symptom severity above the diagnostic threshold following trauma exposure, which was initially stable over time and later began to gradually improve. Although results indicate symptoms eventually began to decline, this effect was gradual; most participants continued to meet or exceed the PTSD provisional diagnostic threshold long after trauma exposure. We identified several predictors and correlates of symptom course, including Hispanic ethnicity, postdeployment social support, and co-occurring psychopathology. Results highlight the heterogeneous nature of PTSD symptom course following trauma exposure and the urgency of the need to ensure access to evidence-based care and to improve available treatments. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Sex differences in traumatic stress reactivity in rats with and without a history of alcohol drinking

BACKGROUND

Alcohol misuse and post-traumatic stress disorder (PTSD) are highly comorbid, and treatment outcomes are worse in individuals with both conditions. Although more men report experiencing traumatic events than women, the lifetime prevalence of PTSD is twice as high in females. Despite these data trends in humans, preclinical studies of traumatic stress reactivity have been performed almost exclusively in male animals.

METHODS

This study was designed to examine sex differences in traumatic stress reactivity in alcohol-naive rats (experiment 1) and rats given intermittent access to 20% ethanol in a 2-bottle choice paradigm for 5 weeks (experiment 2). Animals were exposed to predator odor (bobcat urine) and tested for contextual avoidance 24 h later; unstressed controls were never exposed to predator odor. We evaluated changes in physiological arousal using the acoustic startle response (ASR) test at day 2 post-stress and anxiety-like behavior measured in the elevated plus-maze (EPM) at day 17 post-stress. In experiment 3, time course of corticosterone response was examined in male and female rats following exposure to predator odor stress.

RESULTS

Alcohol-naive males and females exposed to predator odor displayed blunted weight gain 24 h post-stress, but only a subset of stressed animals exhibited avoidance behavior. In alcohol-drinking animals, the proportion of avoiders was higher in males than females, and predator odor exposure increased ASR in males only. Stressed females exhibited blunted ASR relative to unstressed females and stressed males, regardless of alcohol drinking history. Alcohol-experienced females presented lower anxiety-like behavior and higher general activity in the EPM in comparison with alcohol-experienced males. Plasma corticosterone levels were higher in females immediately after predator odor exposure until 60 min post-stress relative to males.

CONCLUSIONS

We report robust sex differences in behavioral and endocrine responses to bobcat urine exposure in adult Wistar rats. Also, males with a history of chronic moderate alcohol drinking exhibited increased traumatic stress reactivity relative to alcohol-drinking females. Our findings emphasize the importance of considering sex as a biological variable in the investigation of traumatic stress effects on physiology and behavior.

The course of (comorbid) trauma-related, dissociative and personality disorders: two year follow up of the Friesland study cohort

Background: There is substantial comorbidity between trauma-related disorders (TRDs), dissociative disorders (DDs) and personality disorders (PDs), especially in patients who report childhood trauma and emotional neglect. However, little is known about the course of these comorbid disorders, despite the fact that this could be of great clinical importance in guiding treatment. Objective: This study describes the two-year course of a cohort of patients with (comorbid) TRDs, DDs and PDs and aims to identify possible predictors of course. Possible gender differences will be described, as well as features of non-respondents. Method: Patients (N = 150) referred to either a trauma treatment program or a PD treatment program were assessed using five structured clinical interviews for diagnosing TRDs, DDs, PDs and trauma histories. Three self-report questionnaires were used to assess general psychopathology, dissociative symptoms and personality pathology in a more dimensional way. Data on demographics and received treatment were obtained using psychiatric records. We described the cohort after a two-year follow-up and used t-tests or chi-square to test possible differences between respondents and non-respondents and between women and men. We used regression analysis to identify possible course predictors. Results: A total of 85 (56.7%) of the original 150 patients participated in the follow-up measurement. Female respondents reported more sexual abuse than female non-respondents. Six patients (4.0%; all women) died because of suicide. Levels of psychopathology significantly declined during the follow-up period, but only among women. Gender was the only significant predictor of change. Conclusions: Comorbidity between TRDs, DDs and PDs was more the rule than the exception, pleading for a more dimensional and integrative view on pathology following childhood trauma and emotional neglect. Courses significantly differed between men and women, advocating more attention to gender in treatment and future research.