Clinical presentations in combat veterans diagnosed with posttraumatic stress disorder

Prevalence of the dissociative subtype of post-traumatic stress disorder: a systematic review and meta-analysis

The dissociative subtype of post-traumatic stress disorder (PTSD-DS) was introduced in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), and is characterised by symptoms of either depersonalisation or derealisation, in addition to a diagnosis of post-traumatic stress disorder (PTSD). This systematic review and meta-analysis sought to estimate the point prevalence of current PTSD-DS, and the extent to which method of assessment, demographic and trauma variables moderate this estimate, across different methods of prevalence estimation. Studies included were identified by searching MEDLINE (EBSCO), PsycInfo, CINAHL, Academic Search Complete and PTSDpubs, yielding 49 studies that met the inclusion criteria (N = 8214 participants). A random-effects meta-analysis estimated the prevalence of PTSD-DS as 38.1% (95% CI 31.5-45.0%) across all samples, 45.5% (95% CI 37.7-53.4%) across all diagnosis-based and clinical cut-off samples, 22.8% (95% CI 14.8-32.0%) across all latent class analysis (LCA) and latent profile analysis (LPA) samples and 48.1% (95% CI 35.0-61.3%) across samples which strictly used the DSM-5 PTSD criteria; all as a proportion of those already with a diagnosis of PTSD. All results were characterised by high levels of heterogeneity, limiting generalisability. Moderator analyses mostly failed to identify sources of heterogeneity. PTSD-DS was more prevalent in children compared to adults, and in diagnosis-based and clinical cut-off samples compared to LCA and LPA samples. Risk of bias was not significantly related to prevalence estimates. The implications of these results are discussed further.

Symptom overreporting and dissociative experiences: A qualitative review

We discuss a phenomenon that has received little attention to date in research on dissociative phenomena, namely that self-reports of these phenomena overlap with the tendency to overendorse eccentric items. We review the literature documenting the dissociation-overreporting link and then briefly discuss various interpretations of this link: (1) overreporting is an artifact of measuring dissociative symptoms; (2) dissociative psychopathology engenders overreporting of eccentric symptoms through fantasy proneness or impairments in internal monitoring; (3) an overreporting response style as is evident in malingerers, for example, promotes reports of dissociative symptoms. These three interpretations are not mutually exclusive. Also, the dissociation-overreporting link may have different origins among different samples. Because overreporting may introduce noise in datasets, we need more research specifically aimed at disentangling the dissociation-overreporting link. We suggest various avenues to accomplish this goal.

Assessment of dissociation among combat-exposed soldiers with and without posttraumatic stress disorder

BACKGROUND

Dissociation is a disruption of and/or discontinuity in the normal, subjective integration of one or more aspects of psychological functioning, including memory, identity, consciousness, perception, and motor control. A limited number of studies investigated combat-related dissociation.

OBJECTIVE

The primary aim of this study was to evaluate the relationship between dissociative symptoms and combat-related trauma.

METHOD

This study included 184 individuals, including 84 patients who were exposed to combat and diagnosed with posttraumatic stress disorder (PTSD) (Group I), 50 subjects who were exposed to combat but were not diagnosed with PTSD (Group II), and 50 healthy subjects without combat exposure (Group III). The participants were evaluated using the Dissociative Experiences Scale (DES) to determine their total and sub-factor (i.e., amnesia, depersonalization/derealization, and absorption) dissociative symptom levels. In addition, Group I and Group II were compared with respect to the relationship between physical injury and DES scores.

RESULTS

The mean DES scores (i.e., total and sub-factors) of Group I were higher than those of Group II (p<0.001), and Group II's mean DES scores (i.e., total and sub-factors) were higher than those of Group III (p<0.001). Similarly, the number of subjects with high total DES scores (i.e.,>30) was highest in Group I, followed by Group II and Group III. When we compared combat-exposed subjects with high total DES scores, Group I had higher scores than Group II. In contrast, no relationship between the presence of bodily injury and total DES scores could be demonstrated. In addition, our results demonstrated that high depersonalization/derealization factor scores were correlated with bodily injury in PTSD patients. A similar relationship was found between high absorption factor scores and bodily injury for Group II.

CONCLUSIONS

Our results demonstrated that the level of dissociation was significantly higher in subjects with combat-related PTSD than in subjects without combat-related PTSD. In addition, combat-exposed subjects without PTSD also had higher dissociation levels than healthy subjects without combat experience.

Implementing an Assessment Clinic in a Residential PTSD Program

Creating useful treatment plans can help improve services to consumers of mental health services. As more evidence-based practices are implemented, deciding what treatment, at what time, for whom becomes an important factor in facilitating positive outcomes. Readiness for trauma-focused treatments for Posttraumatic Stress Disorder (PTSD) such as Cognitive Processing Therapy or Prolonged Exposure Therapy may influence whether an individual can successfully complete either protocol. In addition, components of adjunctive therapies such as Acceptance and Commitment Therapy or Dialectical Behavior Therapy may be useful in moving a particular patient toward readiness and successful completion of treatment. Psychological assessment adds valuable data to inform these types of treatment decisions. This paper describes the implementation of a psychological assessment clinic in a residential PTSD treatment setting. Barriers to implementation, use of the data, and Veterans’ reactions to the feedback provided to them are included.

Dysregulation in microRNA expression is associated with alterations in immune functions in combat veterans with post-traumatic stress disorder

While the immunological dysfunction in combat Veterans with post-traumatic stress disorder (PTSD) has been well documented, the precise mechanisms remain unclear. The current study evaluated the role of microRNA (miR) in immunological dysfunction associated with PTSD. The presence of peripheral blood mononuclear cells (PBMC) and various lymphocyte subsets in blood collected from PTSD patients were analyzed. Our studies demonstrated that the numbers of both PBMC and various lymphocyte subsets increased significantly in PTSD patients. When T cells were further analyzed, the percentage of Th1 cells and Th17 cells increased, regulatory T cells(Tregs) decreased, while Th2 cells remained unaltered in PTSD patients. These data correlated with increased plasma levels of IFN-γ and IL-17 while IL-4 showed no significant change. The increase in PBMC counts, Th1 and Th17 cells seen in PTSD patients correlated with the clinical scores. High-throughput analysis of PBMCs for 1163 miRs showed that the expression of a significant number of miRs was altered in PTSD patients. Pathway analysis of dysregulated miRs seen in PTSD patients revealed relationship between selected miRNAs and genes that showed direct/indirect role in immunological signaling pathways consistent with the immunological changes seen in these patients. Of interest was the down-regulation of miR-125a in PTSD, which specifically targeted IFN-γ production. Together, the current study demonstrates for the first time that PTSD was associated with significant alterations in miRNAs, which may promote pro-inflammatory cytokine profile. Such epigenetic events may provide useful tools to identify potential biomarkers for diagnosis, and facilitate therapy of PTSD.

Internalizing and externalizing classes in posttraumatic stress disorder: a latent class analysis

Using latent class analysis (LCA) the typology of personality profiles of veterans with posttraumatic stress disorder (PTSD) was examined based on internalizing/externalizing dimensions of psychopathology. Latent class analysis on Minnesota Multiphasic Personality Inventory-2 (MMPI-2) Personality Psychopathology-5 (PSY-5) scale data from 299 Australian combat veterans with PTSD supported the model, identifying an optimal 4-class solution, with PTSD externalizing class defined by aggressiveness and disconstraint, high and moderate internalizing classes differentiated on the extent of elevations in introversion and negative emotionality and elevation of psychoticism in the high internalizing class and a simple PTSD class with normal range scores. The model was validated using external self-report and psychiatric-interview-derived diagnoses. A second exploratory LCA using broader comorbidity indicators (MMPI-2 Restructured Clinical scales) demonstrated some support for, although limitations in, using nonpersonality measures to identify these classes directly.

Identifying PTSD personality subtypes in a workplace trauma sample

The authors sought to identify personality clusters derived from the Minnesota Multiphasic Personality Inventory-2 (MMPI-2) Personality Psychopathology Five Scales in a sample of workplace claimants with posttraumatic stress disorder (PTSD). Three clusters--low pathology, internalizing, and externalizing were recovered similar to those obtained by M. W. Miller and colleagues (2003, 2004, 2007) in samples of combat veterans and sexual assault victims. Internalizers and externalizers scored comparably on measures of PTSD symptom severity, general distress, and negative affect. Internalizers were uniquely characterized by anhedonia and depressed mood; externalizers by antisocial behavior, substance abuse, and anger/aggression.

MMPI-2 profiles in civilian PTSD: an examination of differential responses between victims of crime and industrial accidents

The authors studied MMPI-2 profiles of workers (N = 83) diagnosed with posttraumatic stress disorder (PTSD) and a control group comprising workers with chronic pain (N = 40). Significant differences were seen in profiles between the PTSD groups and the control group, and the authors compared the PTSD profiles according to exposure to two different kinds of traumatic incidents: industrial accidents or criminal events. They found differences in profile elevations based on the type of event: The level of distress and fear is greater in PTSD victims of crime, and the results also suggest that victims of crime are more suspicious and guarded compared with accident victims. Theoretically based reasons for the differences in profile elevations between the two PTSD groups are discussed.

Aggression among combat veterans: relationships with combat exposure and symptoms of posttraumatic stress disorder, dysphoria, and anxiety

Prior research has revealed heightened aggressive behavior among veterans with PTSD. This study tested a model examining the interrelationships among combat exposure, posttraumatic stress disorder (PTSD) symptoms, dysphoric symptoms, and anxiety symptoms in predicting aggressive behavior in a sample of 265 male combat veterans seeking diagnostic assessment of PTSD. Combat exposure was indirectly associated with aggression primarily through its relationship with PTSD symptoms. Symptoms of PTSD were directly related to aggression, and indirectly related to aggression through dysphoric symptoms. Results highlight the role of PTSD symptoms and dysphoric symptoms with respect to aggressive behavior among this population, and suggest the relevance of aggression theory to the study of combat veterans.

Post-traumatic stress disorder: evidence-based research for the third millennium

The stress that results from traumatic events precipitates a spectrum of psycho-emotional and physiopathological outcomes. Post-traumatic stress disorder (PTSD) is a psychiatric disorder that results from the experience or witnessing of traumatic or life-threatening events. PTSD has profound psychobiological correlates, which can impair the person's daily life and be life threatening. In light of current events (e.g. extended combat, terrorism, exposure to certain environmental toxins), a sharp rise in patients with PTSD diagnosis is expected in the next decade. PTSD is a serious public health concern, which compels the search for novel paradigms and theoretical models to deepen the understanding of the condition and to develop new and improved modes of treatment intervention. We review the current knowledge of PTSD and introduce the role of allostasis as a new perspective in fundamental PTSD research. We discuss the domain of evidence-based research in medicine, particularly in the context of complementary medical intervention for patients with PTSD. We present arguments in support of the notion that the future of clinical and translational research in PTSD lies in the systematic evaluation of the research evidence in treatment intervention in order to insure the most effective and efficacious treatment for the benefit of the patient.