Dissociative Posttraumatic Stress Disorder Research Articles

A latent class analysis of dissociative PTSD subtype among Chinese adolescents following the COVID-19 pandemic and lockdown

BackgroundThe COVID-19 pandemic and related policies have amplified the vulnerability of adolescents to the development of posttraumatic stress disorder (PTSD) and dissociation symptoms. This study sought to explore the profile patterns and psychopathological characteristics of co-occurring PTSD and dissociation symptoms in Chinese adolescents. MethodsA total of 57,984 junior and senior high school students in Deyang City, China were recruited between July 13 and July 19, 2020. PTSD and dissociation symptoms, risk factors, and functional impairment variables were assessed using the Global Psychotrauma Screen for Teenagers (GPS-T) instrument. Latent class analysis (LCA) was employed to examine the phenomenology and risk factors of co-occurring PTSD and dissociation symptoms. Analysis of Variance (ANOVA) was utilized to investigate differences in COVID-19 pandemic-related exposure and functional impairment across distinct symptom profiles. ResultsA 4-class model was selected as the optimal solution, comprising subgroups of low symptom, predominant PTSD symptom, predominant dissociation symptom, and PTSD-dissociation symptom. Class membership could be significantly predicted by other stressful experiences, social support, childhood maltreatment and psychiatric histories. The PTSD-dissociation symptom class exhibited the most severe COVID-19 pandemic-related exposure and functional impairment among all classes. LimitationsThe cross-sectional design, Chinese cultural background, online survey method and oversimple measurements were the limitations. ConclusionsOur findings extend existing knowledge about the coexisting patterns of PTSD and dissociation symptoms in adolescents, which could assist in identifying high-risk youths. Furthermore, our findings offer recommendations for shaping public health policies and formulating effective clinical interventions for adolescents following the COVID-19 pandemic and lockdown.

Therapist-assisted online psychological therapies differing in trauma focus for post-traumatic stress disorder (STOP-PTSD): a UK-based, single-blind, randomised controlled trial

Many patients are currently unable to access psychological treatments for post-traumatic stress disorder (PTSD), and it is unclear which types of therapist-assisted internet-based treatments work best. We aimed to investigate whether a novel internet-delivered cognitive therapy for PTSD (iCT-PTSD), which implements all procedures of a first-line, trauma-focused intervention recommended by the UK National Institute for Health and Care Excellence (NICE) for PTSD, is superior to internet-delivered stress management therapy for PTSD (iStress-PTSD), a comprehensive cognitive behavioural treatment programme focusing on a wide range of coping skills. We did a single-blind, randomised controlled trial in three locations in the UK. Participants (≥18 years) were recruited from UK National Health Service (NHS) Improving Access to Psychological Therapies (IAPT) services or by self-referral and met DSM-5 criteria for PTSD to single or multiple events. Participants were randomly allocated by a computer programme (3:3:1) to iCT-PTSD, iStress-PTSD, or a 3-month waiting list with usual NHS care, after which patients who still met PTSD criteria were randomly allocated (1:1) to iCT-PTSD or iStress-PTSD. Randomisation was stratified by location, duration of PTSD (<18 months or ≥18 months), and severity of PTSD symptoms (high vs low). iCT-PTSD and iStress-PTSD were delivered online with therapist support by messages and short weekly phone calls over the first 12 weeks (weekly treatment phase), and three phone calls over the next 3 months (booster phase). The primary outcome was the severity of PTSD symptoms at 13 weeks after random assignment, measured by self-report on the PTSD Checklist for DSM-5 (PCL-5), and analysed by intention-to-treat. Safety was assessed in all participants who started treatment. Process analyses investigated acceptability and compliance with treatment, and candidate moderators and mediators of outcome. The trial was prospectively registered with the ISRCTN registry, ISRCTN16806208. Of the 217 participants, 158 (73%) self-reported as female, 57 (26%) as male, and two (1%) as other; 170 (78%) were White British, 20 (9%) were other White, six (3%) were Asian, ten (5%) were Black, eight (4%) had a mixed ethnic background, and three (1%) had other ethnic backgrounds. Mean age was 36·36 years (SD 12·11; range 18-71 years). 52 (24%) participants met self-reported criteria for ICD-11 complex PTSD. Fewer than 10% of participants dropped out of each treatment group. iCT-PTSD was superior to iStress-PTSD in reducing PTSD symptoms, showing an adjusted difference on the PCL-5 of -4·92 (95% CI -8·92 to -0·92; p=0·016; standardised effect size d=0·38 [0·07 to 0·69]) for immediate allocations and -5·82 (-9·59 to -2·04; p=0·0027; d=0·44 [0·15 to 0·72]) for all treatment allocations. Both treatments were superior to the waiting list for PCL-5 at 13 weeks (d=1·67 [1·23 to 2·10] for iCT-PTSD and 1·29 [0·85 to 1·72] for iStress-PTSD). The advantages in outcome for iCT-PTSD were greater for participants with high dissociation or complex PTSD symptoms, and mediation analyses showed both treatments worked by changing negative meanings of the trauma, unhelpful coping, and flashback memories. No serious adverse events were reported. Trauma-focused iCT-PTSD is effective and acceptable to patients with PTSD, and superior to a non-trauma-focused cognitive behavioural stress management therapy, suggesting that iCT-PTSD is an effective way of delivering the contents of CT-PTSD, one of the NICE-recommended first-line treatments for PTSD, while reducing therapist time compared with face-to-face therapy. Wellcome Trust, UK National Institute for Health and Care Research Oxford Health Biomedical Research Centre.

Differing associations of depersonalization with physiological response during rest and breath-focused mindfulness in a trauma-exposed female population

BackgroundDissociative and posttraumatic stress disorder (PTSD) symptoms are commonly co-occurring responses to psychological trauma. Yet, these two groups of symptoms appear to be related to diverging patterns of physiological response. To date, few studies have examined how specific dissociative symptoms, namely, depersonalization and derealization, relate to skin conductance response (SCR), a marker of autonomic function, within the context of PTSD symptoms. We examined associations among depersonalization, derealization, and SCR during two conditions – resting control and breath-focused mindfulness – in the context of current PTSD symptoms. MethodsSixty-eight trauma-exposed women (82.4% Black; Mage = 42.5, SDage = 12.1) were recruited from the community for a breath-focused mindfulness study. SCR data were collected during alternating resting control and breath-focused mindfulness conditions. Moderation analyses were conducted to examine relations among dissociative symptoms, SCR, and PTSD for these different conditions. ResultsModeration analyses revealed that depersonalization was linked to lower SCR during resting control, B = 0.0005, SE = 0.0002, p = .006, in participants low-to-moderate PTSD symptoms; however, depersonalization was associated with higher SCR during breath-focused mindfulness, B = −0.0006, SE = 0.0003, p = .029, in individuals with similar levels of PTSD symptoms. No significant interaction between derealization and PTSD symptoms on SCR was observed. ConclusionsDepersonalization symptoms may associate with physiological withdrawal during rest, but greater physiological arousal during effortful emotion regulation in individuals with low-to moderate levels of PTSD, which has significant implications for barriers to treatment engagement as well as treatment selection in this population.

Using Quantitative and Qualitative Rorschach Data within a Multi-Method, Forensic Assessment of Dissociative Posttraumatic Stress Disorder

Using Quantitative and Qualitative Rorschach Data within a Multi-Method, Forensic Assessment of Dissociative Posttraumatic Stress Disorder

A latent profile analysis of the dissociative subtype of PTSD in a sample of UK Armed Forces veterans residing in Northern Ireland

Background: Posttraumatic stress disorder (PTSD) and dissociation have long been associated with each other. In recent years, studies have examined support for the dissociative subtype of PTSD in several different populations. To date, no study has examined whether this subtype exists in UK Armed Forces military veterans residing in Northern Ireland. Northern Ireland has a history of prolonged civil conflict, differentiating the veterans who live in the region from veterans who live in the remainder of the United Kingdom; and increasing the likelihood that they will experience mental health difficulties. Methods: Data was collected through a cross-sectional, self-report survey from military veterans living in Northern Ireland. The effective sample for the current study was 834 veterans (90.38% males, mean age 55.81 years). A latent profile analysis of PTSD and dissociative indicators was conducted to examine the existence of the dissociative PTSD subtype. Results: Four quantitatively different latent profiles were identified; Non-symptomatic, Low PTSD, Moderate PTSD and High PTSD. There was no evidence of a dissociative PTSD subtype. Several military-type variables differentially predicted membership in the latent profiles, including combat exposure, length of service, physical injuries during service and having been medically discharged. Conclusions: The results do not support the Subtype model of the relationship between PTSD and dissociation. However, they have important implications for clinicians working with veterans in the region, as it appears that dissociation is an integral part of the PTSD presentation in Northern Irish veterans.

Impact of urban birth and upbringing on expression of psychosis in a Chinese undergraduate population

BackgroundUrban birth and upbringing show consistent associations with psychotic illness but the key urban exposures remain unknown. Associations with psychotic-like experiences (PEs) are inconsistent. These could be confounded by common mental disorders associated with PEs. Furthermore, associations between PEs and urban exposures may not extrapolate to psychotic disorders such as schizophrenia.MethodsAnnual cross-sectional surveys among first year Chinese undergraduates 2014–2019 (n = 47,004). Self-reported, hierarchical categorisation of psychosis: from psychoticism, paranoid ideation, schizotypal symptoms, nuclear syndrome using SCL-90-R, to clinical diagnosis of schizophrenia. Depressive symptoms using PHQ 9. Dissociative symptoms and posttraumatic stress disorder (PTSD) measured using PCL-C. Etiological factors of family history and childhood disadvantage. We studied effects of urban birth, urban living and critical times of exposure in childhood on psychosis phenotypes.ResultsAssociations with urbanicity were found only after adjustments for depression. Urban birth was associated with paranoia (AOR 1.34, 1.18–1.53), schizotypal symptoms (AOR 1.59, 1.29–1.96), and schizophrenia (AOR 2.07, 1.10–3.87). The same phenotypes showed associations with urban residence > 10 years. Only schizophrenia showed an association with urban exposure birth-3 years (AOR 7.01, 1.90–25.86). Child maltreatment was associated with both psychosis and depression. Urbanicity measured across the total sample did not show any associations with demography, family history of psychosis, or child maltreatment. Sensitivity analysis additionally adjusting for dissociative symptoms and PTSD showed the same pattern of findings.ConclusionsUrban birth and urban living showed a hierarchical pattern of increasing associations from paranoid ideation to schizotypal disorder to schizophrenia, confirming that associations for psychotic experiences could be extrapolated to schizophrenia, but only after adjusting for confounding from depression, dissociative symptoms and PTSD. Several etiological factors were the same for psychosis and depression. Future studies of PEs should adjust for confounding from common mental disorders and dissociative symptoms. Effects of urbanicity on psychosis were not explained by demography, family history of mental disorder, or child maltreatment.

The contributions of emotion regulation difficulties and dissociative symptoms to functional impairment among civilian inpatients with posttraumatic stress symptoms.

Functional impairment among individuals with posttraumatic stress disorder (PTSD) represents a significant factor in recovery. Critically, functional impairment appears to persist following remission of PTSD symptoms. To date, work investigating functional impairment among individuals with PTSD has focused on PTSD symptom clusters, excluding other relevant symptoms, including emotion regulation difficulties and dissociative symptoms. Emerging work suggests that these symptoms may serve as important predictors of functional impairment among individuals with PTSD. The present study investigated the contributions of difficulties with emotion regulation, dissociative symptoms, and individual PTSD symptom clusters to functional impairment among an inpatient civilian sample who completed self-report assessments of PTSD symptoms, functional impairment, emotion regulation difficulties, and dissociative symptoms, upon admission to the program. Participants met criteria for probable PTSD as per the PTSD checklist for Diagnostic and Statistical Manual of Mental Disorders, fifth edition (DSM-5) and reported high rates of exposure to childhood abuse and neglect. Emotion regulation difficulties contributed significantly, while dissociative symptoms and PTSD arousal and reactivity symptoms showed a signal toward contributing significantly to a model accounting for variance in functional impairment among individuals with probable PTSD. Differential patterns of contributors emerged for the various domains of functional impairment measured. These findings add to a growing body of literature highlighting the importance of emotion regulation difficulties, dissociative symptoms, and arousal and reactivity symptoms in contributing to functional impairment in this disorder. Recovery to premorbid functional status in PTSD may require interventions that target directly these symptoms. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Classifying heterogeneous presentations of PTSD via the default mode, central executive, and salience networks with machine learning.

Intrinsic connectivity networks (ICNs), including the default mode network (DMN), the central executive network (CEN), and the salience network (SN) have been shown to be aberrant in patients with posttraumatic stress disorder (PTSD). The purpose of the current study was to a) compare ICN functional connectivity between PTSD, dissociative subtype PTSD (PTSD+DS) and healthy individuals; and b) to examine the use of multivariate machine learning algorithms in classifying PTSD, PTSD+DS, and healthy individuals based on ICN functional activation. Our neuroimaging dataset consisted of resting-state fMRI scans from 186 participants [PTSD (n=81); PTSD+DS (n=49); and healthy controls (n=56)]. We performed group-level independent component analyses to evaluate functional connectivity differences within each ICN. Multiclass Gaussian Process Classification algorithms within PRoNTo software were then used to predict the diagnosis of PTSD, PTSD+DS, and healthy individuals based on ICN functional activation. When comparing the functional connectivity of ICNs between PTSD, PTSD+DS and healthy controls, we found differential patterns of connectivity to brain regions involved in emotion regulation, in addition to limbic structures and areas involved in self-referential processing, interoception, bodily self-consciousness, and depersonalization/derealization. Machine learning algorithms were able to predict with high accuracy the classification of PTSD, PTSD+DS, and healthy individuals based on ICN functional activation. Our results suggest that alterations within intrinsic connectivity networks may underlie unique psychopathology and symptom presentation among PTSD subtypes. Furthermore, the current findings substantiate the use of machine learning algorithms for classifying subtypes of PTSD illness based on ICNs.

Post Traumatic Stress Disorder (PTSD) and It’s Associated Factors among Secondary Level Students in Chautara Municipality, Nepal

Children and adolescents are more prone to developing Post Traumatic Stress Disorders. Objective of this study was to assess the magnitude of Post Traumatic Stress Disorder and associated factors among secondary level students in Chautara Municipality, Nepal. A cross sectional study was conducted among 249 secondary level students. Data were collected using population proportionate sampling method along with UCLA PTSD RI with 31 questionnaires DSM V tool was used to assess the PTSD symptom. Questionnaire was design to obtain socio demographic factor and earthquake exposure. Factor associated with PTSD development was assessed through chi square and binary logistic regression. Mean age of respondents was 15.42±1.079 years. Majority of them were middle adolescents (74.3%) and 25.7 percent were early adolescents. More than half of respondents were female 54.6 percent. This study revealed that PTSD was found to be among 27(10.8%) respondents and dissociative subtype PTSD was among 14(5.6%) respondents. Age was significantly associated with development of PTSD. Earthquake exposures like financial constraints after earthquake food deficiency displacement due to earthquake was the major factors associated with PTSD development. Psychological tutorship for PTSD is found to be protective factors for PTSD development in adolescents. PTSD was quite high among the secondary level students after six month of earthquake in Chautara municipality, Sindupalchwok district and psychological tutorship and humanitarian program for traumatized students could prevent development of PTSD.&#x0D; Key words: Post traumatic stress disorder; Associated factors; Earthquake; Secondary levels students

Dissociative subtype of posttraumatic stress disorder in women in partial and residential levels of psychiatric care

ABSTRACT The dissociative subtype of posttraumatic stress disorder (PTSD) is estimated to characterize about 12-30% of those with PTSD. Some research links this subtype with increased severity of PTSD symptoms compared to samples with “classic” PTSD. However, prevalence and severity rates reported in the literature have varied. One possible explanation for these discrepancies could be related to where the populations were sampled. Therefore, we investigated whether these differences are still observed when holding level of care constant. We collected data from 104 women at a partial and residential psychiatric hospital program focused on trauma-related disorders. Participants completed self-report questionnaires assessing trauma exposure, symptoms and provisional diagnosis of PTSD, trauma-related thoughts and beliefs, and feelings of shame. All participants reported a history of childhood and/or adulthood trauma exposure. Eighty-eight (85%) met criteria for PTSD, and of those, seventy-three (83%) met criteria for the dissociative subtype as assessed by the Dissociative Subtype of PTSD Scale. A series of independent t-tests revealed no significant differences between the “classic” and dissociative PTSD groups with respect to lifetime or childhood trauma exposure, posttraumatic cognitions, shame, or overall PTSD severity. Our results suggest that samples with classic PTSD and the dissociative subtype may not differ in some types of symptom severity when holding level of care constant. Importantly, however, we found at partial/residential level of care the majority of patients with PTSD were dissociative. Given the elevated prevalence rate in this sample, these findings support the need to assess dissociative symptoms, particularly in more acute psychiatric settings.

Death anxiety and spiritual intelligence as predictors of dissociative posttraumatic stress disorder in Greek first responders: A moderation model.

Death anxiety and spiritual intelligence as predictors of dissociative posttraumatic stress disorder in Greek first responders: A moderation model.

Understanding the role art therapy can take in treating veterans with chronic post-traumatic stress disorder

Individuals who are highly avoidant and/or have dissociative post-traumatic stress disorder (PTSD) presentations may be less likely to engage in evidence-based trauma treatments, and consequently are more likely to drop out of therapy. These individuals may benefit from approaches that provide alternatives to verbal or cognitive processes to achieve therapeutic outcomes.In recent years, a number of research studies have been undertaken at the UK veterans’ mental health charity Combat Stress to try to understand the role art therapy can take in treating veterans with chronic PTSD. An overview of the findings is presented, along with suggested treatment and ethical guidelines, and recommendations for innovative ways to conduct research on the value of art therapy for veterans. Art therapy is shown to offer promise as a treatment for the overcoming of PTSD-related avoidance symptoms and for increasing self-awareness. Furthermore, the work created in sessions captures snapshots of meaning that veterans can use as a form of communication outside of the art therapy space, as active working documents. In this way, art therapy can assist veterans to understand and communicate their inner experiences, and to engage in trauma therapy.

Problems with the dissociative subtype of posttraumatic stress disorder in DSM-5

The diagnostic criteria set for posttraumatic stress disorder (PTSD) has gradually evolved from DSM-III, to DSM-IV, to DSM-5. Besides a broadening of the event criterion for PTSD, the symptom domain now involves many different brain circuits and types of symptoms, including: fear and anxiety; anger and aggression; negative cognition and mood; hypo-arousal; and dissociative symptoms. The dissociative subtype of PTSD in DSM-5 is defined by the presence of depersonalization or derealization. However, the diagnostic criteria for PTSD also include dissociative flashbacks and dissociative amnesia. If these symptoms were included in the definition of the dissociative type of PTSD in future editions of the manual, then most cases of PTSD would be dissociative in nature, and non-dissociative cases would be a minority subtype. There does not appear to be any sound conceptual reason for excluding amnesia and flashbacks from the criteria for dissociative PTSD.

Assessing the existence of dissociative PTSD in sub-acute patients of whiplash

ABSTRACTNumerous studies investigating dissociative posttraumatic stress disorder (D-PTSD) have emerged. However, there is a lack of studies investigating D-PTSD following a wider range of traumatic exposure. Thus, the present study investigates D-PTSD using latent class analysis (LCA) in sub-acute patients of whiplash and associated risk factors. The results of LCA showed a three-class solution primarily distributed according to posttraumatic stress disorder (PTSD) symptom severity and thus no indication of D-PTSD. Dissociative symptoms, psychological distress (i.e. anxiety/depression), and pain severity significantly predicted PTSD severity. Combined, the results support the component model of dissociation and PTSD, while still stressing the importance of dissociative symptoms when planning treatment for PTSD.

The dissociative post-traumatic stress disorder (PTSD) subtype: A treatment outcome cohort study in veterans with PTSD.

Dissociation is a prevalent phenomenon among veterans with post-traumatic stress disorder (PTSD) that may interfere with the effectiveness of treatment. This study aimed to replicate findings of a dissociative PTSD subtype, to identify corresponding patterns in coping style, symptom type, and symptom severity, and to investigate its impact on post-traumatic symptom improvement. Latent profile analysis (LPA) was applied to baseline data from 330 predominantly (97%) male treatment-seeking veterans (mean age 39.5years) with a probable PTSD. Multinomial logistic models were used to identify predictors of dissociative PTSD. Eighty veterans with PTSD that commenced with psychotherapy were invited for a follow-up measure after 6months. The majority (n=64, 80% response rate) completed the follow-up measure. Changes in post-traumatic stress between baseline and follow-up were explored as a continuous distal outcome. Latent profile analysis revealed four distinct patient profiles: 'low' (12.9%), 'moderate' (33.2%), 'severe' (45.1%), and 'dissociative' (8.8%) PTSD. The dissociative PTSD profile was characterized by more severe pathology levels, though not post-traumatic reactions symptom severity. Veterans with dissociative PTSD benefitted equally from PTSD treatment as veterans with non-dissociative PTSD with similar symptom severity. Within a sample of veterans with PTSD, a subsample of severely dissociative veterans was identified, characterized by elevated severity levels on pathology dimensions. The dissociative PTSD subtype did not negatively impact PTSD treatment. The present findings confirmed the existence of a distinct subgroup veterans that fit the description of dissociative PTSD. Patients with dissociative PTSD subtype symptoms uniquely differed from patients with non-dissociative PTSD in the severity of several psychopathology dimensions. Dissociative and non-dissociative PTSD patients with similar post-traumatic severity levels showed similar levels of improvement after PTSD treatment. The observational design and small sample size caution interpretation of the treatment outcome data. The IES-R questionnaire does not assess all PTSD DSM-IV diagnostic criteria (14 of 17), although it is considered a valid measure for an indication of PTSD.

Dissociative features in posttraumatic stress disorder: A latent profile analysis.

The fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) characterizes the dissociative subtype of posttraumatic stress disorder (PTSD) in terms of the individual meeting the criteria for PTSD and additionally reporting symptoms of depersonalization and/or derealization. The current study aimed to examine whether a dissociative PTSD profile may include alternative features of dissociation and whether it could be differentiated from a nondissociative PTSD profile on certain psychopathologies and demographics. Data from 309 trauma-exposed participants, collected through Amazon Mechanical Turk, were subjected to latent profile analysis. Regression analyses were used to examine the predictors of latent classes. Three discrete profiles named Baseline, PTSD, and Dissociative profile were uncovered. All examined features of dissociation were significantly elevated in the Dissociative profile. Anxiety, male sex, being employed, and having a minority racial background significantly predicted the Dissociative profile relative to the PTSD profile. The study points to the importance of alternative symptoms of dissociation in the dissociative PTSD subtype beyond the symptoms of depersonalization and derealization. (PsycINFO Database Record

Shame, Dissociation, and Complex PTSD Symptoms in Traumatized Psychiatric and Control Groups: Direct and Indirect Associations With Relationship Distress

Elevated shame and dissociation are common in dissociative identity disorder (DID) and chronic posttraumatic stress disorder (PTSD) and are part of the constellation of symptoms defined as complex PTSD. Previous work examined the relationship between shame, dissociation, and complex PTSD and whether they are associated with intimate relationship anxiety, relationship depression, and fear of relationships. This study investigated these variables in traumatized clinical samples and a nonclinical community group. Participants were drawn from the DID (n = 20), conflict-related chronic PTSD (n = 65), and nonclinical (n = 125) populations and completed questionnaires assessing the variables of interest. A model examining the direct impact of shame and dissociation on relationship functioning, and their indirect effect via complex PTSD symptoms, was tested through path analysis. The DID sample reported significantly higher dissociation, shame, complex PTSD symptom severity, relationship anxiety, relationship depression, and fear of relationships than the other two samples. Support was found for the proposed model, with shame directly affecting relationship anxiety and fear of relationships, and pathological dissociation directly affecting relationship anxiety and relationship depression. The indirect effect of shame and dissociation via complex PTSD symptom severity was evident on all relationship variables. Shame and pathological dissociation are important for not only the effect they have on the development of other complex PTSD symptoms, but also their direct and indirect effects on distress associated with relationships.

Can the dissociative PTSD subtype be identified across two distinct trauma samples meeting caseness for PTSD?

For over a century, the occurrence of dissociative symptoms in connection to traumatic exposure has been acknowledged in the scientific literature. Recently, the importance of dissociation has also been recognized in the long-term traumatic response within the DSM-5 nomenclature. Several studies have confirmed the existence of the dissociative posttraumatic stress disorder (PTSD) subtype. However, there is a lack of studies investigating latent profiles of PTSD solely in victims with PTSD. This study investigates the possible presence of PTSD subtypes using latent class analysis (LCA) across two distinct trauma samples meeting caseness for DSM-5 PTSD based on self-reports (N=787). Moreover, we assessed if a number of risk factors resulted in an increased probability of membership in a dissociative compared with a non-dissociative PTSD class. The results of LCA revealed a two-class solution with two highly symptomatic classes: a dissociative class and a non-dissociative class across both samples. Increased emotion-focused coping increased the probability of individuals being grouped into the dissociative class across both samples. Social support reduced the probability of individuals being grouped into the dissociative class but only in the victims of motor vehicle accidents (MVAs) suffering from whiplash. The results are discussed in light of their clinical implications and suggest that the dissociative subtype can be identified in victims of incest and victims of MVA suffering from whiplash meeting caseness for DSM-5 PTSD.

Mindfulness-Related Traits Partially Mediate the Association Between Lifetime and Childhood Trauma Exposure and PTSD and Dissociative Symptoms in a Community Sample Assessed Online

Although theory suggests the relevance of mindfulness and mindfulness-based therapies for understanding relationships between trauma, posttraumatic stress disorder (PTSD), and dissociative experiences, little research has directly compared associations between mindfulness and trauma-related distress versus dissociation, including dissociative trauma-related altered states of consciousness (TRASC). We therefore examined whether mindfulness traits (Five Facet Mindfulness Questionnaire [FFMQ]) partially mediated the relationship between self-reported trauma exposure, whether occurring during childhood or anytime in life, and outcomes of PTSD, dissociative subtype PTSD, and TRASC in 952 trauma-exposed participants surveyed online. The relationships between increased traumatic experiences and PTSD, dissociative PTSD, and TRASC were partially mediated by the decreased capacity for mindful describing, acting with awareness, and non-judging traits, although decreased mindful non-reactivity partially mediated only the association between increased childhood trauma exposure and PTSD symptoms, while increased mindful observing partially mediated the association between increased lifetime trauma exposure and increased PTSD and dissociative symptoms. Our findings suggest that altered or decreased capacity for different facets of trait mindfulness may be one mechanism by which trauma exposure leads to the development of trauma-related distress and dissociation.

Structural brain aberrations associated with the dissociative subtype of post-traumatic stress disorder.

One factor potentially contributing to the heterogeneity of previous results on structural grey matter alterations in adult participants suffering from post-traumatic stress disorder (PTSD) is the varying levels of dissociative symptomatology. The aim of this study was therefore to test whether the recently defined dissociative subtype of PTSD characterized by symptoms of depersonalization and derealization is characterized by specific differences in volumetric brain morphology. Whole-brain MRI data were acquired for 59 patients with PTSD. Voxel-based morphometry was carried out to test for group differences between patients classified as belonging (n = 15) vs. not belonging (n = 44) to the dissociative subtype of PTSD. The correlation between dissociation (depersonalization/derealization) severity and grey matter volume was computed. Patients with PTSD classified as belonging to the dissociative subtype exhibited greater grey matter volume in the right precentral and fusiform gyri as well as less volume in the right inferior temporal gyrus. Greater dissociation severity was associated with greater volume in the right middle frontal gyrus. The results of this first whole-brain investigation of specific grey matter volume in dissociative subtype PTSD indentified structural aberrations in regions subserving the processing and regulation of emotional arousal. These might constitute characteristic biomarkers for the dissociative subtype PTSD.