Subtype Of Posttraumatic Stress Disorder Research Articles

The Dissociative Subtype of Posttraumatic Stress Disorder: Forensic Considerations and Recent Controversies

This article provides an overview of the evidence concerning the dissociative subtype of posttraumatic stress disorder (PTSD) and its relevance in forensic contexts. We discuss best practices for the assessment of the subtype in forensic settings, including consideration of malingering, and the impact of the subtype on witness presentation and potential award determinations. We review recent debate concerning the definition of the subtype and how multivariate analyses can be used to inform the understanding of the relationship between PTSD and dissociation. Altering the definition of the subtype (or of the core PTSD criteria), such as by including additional types of dissociative symptoms, would likely hold major implications for diagnostic prevalence and comorbidity and could substantially affect forensic cases involving the dissociative subtype of PTSD. We suggest that for DSM-6, it would be best to use structural evidence to decide how best to revise the subtype and accurately capture its relationship with the core PTSD symptoms. It is important for forensic experts to be well-versed in the state of the science concerning this condition so as to reliably and validly assess clients and inform triers of fact of the strengths and weaknesses of this body of work.

The dissociative subtype of posttraumatic stress disorder is associated with subcortical white matter network alterations

Posttraumatic stress disorder (PTSD) is characterized by intrusions, avoidance, and hyperarousal while patients of the dissociative subtype (PTSD-D) experience additional dissociative symptoms. A neurobiological model proposes hyper-inhibition of limbic structures mediated by prefrontal cortices to underlie dissociation in PTSD. Here, we tested whether functional alterations in fronto-limbic circuits are underpinned by white matter network abnormalities on a network level. 23 women with PTSD-D and 19 women with classic PTSD participated. We employed deterministic diffusion tractography and graph theoretical analyses. Mean fractional anisotropy (FA) was chosen as a network weight and group differences assessed using network-based statistics. No significant white matter network alterations comprising both frontal and limbic structures in PTSD-D relative to classic PTSD were found. A subsequent whole brain exploratory analysis revealed relative FA alterations in PTSD-D in two subcortical networks, comprising connections between the left amygdala, hippocampus, and thalamus as well as links between the left ventral diencephalon, putamen, and pallidum, respectively. Dissociative symptom severity in the PTSD-D group correlated with FA values within both networks. Our findings suggest fronto-limbic inhibition in PTSD-D may present a dynamic neural process, which is not hard-wired via white matter tracts. Our exploratory results point towards altered fiber tract communication in a limbic-thalamic circuit, which may underlie (a) an initial strong emotional reaction to trauma reminders before conscious regulatory processes are enabled and (b) deficits in early sensory processing. In addition, aberrant structural connectivity in low-level motor regions may present neural correlates for dissociation as a passive threat-response.

A network analysis of posttraumatic stress disorder and dissociation in trauma-exposed adolescents

Posttraumatic stress disorder (PTSD) and dissociation have long been recognized to co-occur, leading the DSM-5 to introduce a dissociative subtype of PTSD into its nomenclature. Most research to date on the dissociative subtype has focused on adults. The current study aimed to extend this research to an adolescent sample and to examine symptom-level associations between PTSD and dissociation using network analysis. The analysis was conducted with 448 trauma-exposed detained US adolescents (24.55% female; mean age 15.98 ± 1.25 years). A network consisting of 20 DSM-5 PTSD symptoms was constructed, followed by a network consisting of 20 PTSD symptoms and five dissociative items. Expected influence bridge centrality was estimated to examine items with the most/strongest cross-construct connections (i.e. between PTSD and dissociation). The PTSD symptoms concentration problems, amnesia and recurrent memories and the dissociative items depersonalization, derealisation and can’t remember things that happened had the highest bridge centrality values. These symptom-level associations extend our understanding of the PTSD-dissociation relationship by pointing to specific symptoms of PTSD and dissociation that may drive the co-morbidity between the two constructs. These findings may inform future intervention efforts.

Uncovering the heterogeneity of posttraumatic stress disorder: Towards a personalized medicine approach for military members and Veterans

Introduction: Recently, there has been substantial interest in exploring the heterogeneity of posttraumatic stress disorder (PTSD) on a neurobiological level, as individuals with PTSD, including military members and Veterans, vary in their presentation of symptoms. Methods: Critically, a dissociative subtype of PTSD (PTSD+DS) has been defined, where a large body of evidence suggests that the unique presentation of symptoms among PTSD+DS patients is associated with aberrant neurobiological underpinnings. Results: PTSD+DS is often characterized by emotion overmodulation, with increased top-down activation from emotion regulation areas, which is associated with emotional detachment, depersonalization, and derealization. This is in stark contrast to the symptoms commonly observed in individuals with PTSD, who exhibit emotion undermodulation, which involves decreased top-down regulation of hyperactive emotion generation areas and is associated with vivid re-experiencing of trauma memories and hyperarousal. Discussion: This article examines a clinical case example that clearly illustrates this heterogeneous presentation of PTSD symptomatology and psychopathology. It discusses the implications this evidence base holds for a neurobiologically-informed, personalized medicine approach to treatment for military members and Veterans.

The impact of brief intensive trauma-focused treatment for PTSD on symptoms of borderline personality disorder

ABSTRACT Background: It is generally recommended to exercise caution in applying trauma-focused treatment to individuals with posttraumatic stress disorder (PTSD) and comorbid borderline personality disorder (BPD). Objective: To investigate the effects of a brief, intensive, direct trauma-focused treatment programme for individuals with PTSD on BPD symptom severity. Methods: Individuals (n = 72) with severe PTSD (87.5% had one or more comorbidities; 52.8% fulfilled the criteria for the dissociative subtype of PTSD) due to multiple traumas (e.g. 90.3% sexual abuse) participated in an intensive eight-day trauma-focused treatment programme consisting of eye movement desensitization and reprocessing (EMDR) and prolonged exposure (PE) therapy, physical activity, and psychoeducation. Treatment did not include any form of stabilization (e.g. emotion regulation training) prior to trauma-focused therapy. Assessments took place at pre- and post-treatment (Borderline Symptom List, BSL-23; PTSD symptom severity, Clinician Administered PTSD Scale for DSM-5, CAPS-5), and across the eight treatment days (PTSD Checklist, PCL-5). Results: Treatment resulted in significant decreases of BPD symptoms (Cohen’s d = 0.70). Of the 35 patients with a positive screen for BPD at pre-treatment, 32.7% lost their positive screen at post-treatment. No adverse events nor dropouts occurred during the study time frame, and none of the patients experienced symptom deterioration in response to treatment. Conclusion: The results suggest that an intensive trauma-focused treatment is a feasible and safe treatment for PTSD patients with clinically elevated symptoms of BPD, and that BPD symptoms decrease along with the PTSD symptoms.

A Network Approach to Studying the Associations Between Posttraumatic Stress Disorder Symptoms and Dissociative Experiences

In recent years, there has been a growing recognition of a dissociative subtype of posttraumatic stress disorder (D‐PTSD), characterized by experiences of depersonalization (DP) and derealization (DR), among individuals with PTSD. Little is known, however, about how experiences of DP and/or DR are associated with the experience of other PTSD symptoms. The central aim of the present paper was to explore the associations among DP, DR, and other PTSD symptoms by means of a network analysis of cross‐sectional data for 557 participants whose overall self‐reported PTSD symptom severity warranted a probable PTSD diagnosis. Three notable findings emerged: (a) a strong association between DP and DR, (b) the identification of DP as the most central symptom in the network, and (c) the discovery that clusters of symptoms in the network were roughly consistent with DSM‐5 PTSD criteria. We discuss these findings in light of some considerations, including the nature of our sample and the limits of interpreting cross‐sectional network models.

Post-traumatic Stress Disorder in Heart Failure Patients: A Test of the Cardiac Disease-induced PTSD Hypothesis

Background:Post-traumatic stress disorder (PTSD) is prevalent in approximately 12% of patients with cardiovascular disease (CVD) and such patients are at risk of further CVD morbidity and mortality. It is unknown whether CVD patients with cardiac and non-cardiac traumatic events leading to PTSD differ in medical comorbidities and psychiatric vulnerabilities. Our objective was to compare heart failure (HF) patients with cardiac and non-cardiac PTSD.Method:A population of HF patients from 3 hospitals underwent a two-step depression and anxiety screening process to identify potential mental health treatment needs. The post-traumatic stress disorder module of the Structured Clinical Interview for DSM-IV Axis-I disorders was used to classify trauma(s) exposure, and other disorders. The patients with PTSD were sub-divided by cardiac related traumas (e.g. myocardial infarction, sudden cardiac arrest) and non-cardiac related traumas (e.g. sexual abuse, interpersonal violence).Results:10 patients met criteria for non-cardiac trauma and 18 patients met criteria for cardiacinduced trauma. There were no significant differences in HF aetiology or severity nor cardiac comorbidities. Time since PTSD, onset was significantly longer for those with non-cardiac PTSD. Among psychiatric comorbidities, alcohol and substance abuse disorders, as well as depression were more prevalent in patients with non-cardiac PTSD.Conclusion:Cardiac related PTSD was associated with less alcohol and substance abuse disorders, and depression by comparison to their non-cardiac induced PTSD counterparts. Ongoing research is required to establish if cardiac-induced PTSD truly reflects a unique subtype of PTSD, and whether there are different treatment needs and therapeutic approaches for this subtype.

Post-traumatic stress disorder psychotic subtype or comorbid psychotic disorder and evaluation of military service ability

Introduction. Recent studies have shown that diagnostic differences in the opinion whether some case is a psychotic subtype of posttraumatic stress disorder (PTSD) or a comorbid psychotic disorder still exist. In a case of mental disorders, a specific nature of military environment requires a detailed evaluation of abilities for military service (MS). Case report. A 34-year old male noncommissioned officer (NCO) showed symptomatology of PTSD (according to the Diagnostic and Statistical Manual of Mental Disorders ? DSM-IV) after experiencing a traumatic event in peacetime conditions. In addition to experiencing trauma as an adult, the patient was also exposed to early-age trauma, when his father committed suicide. After a pharmacotherapy and cognitive behavioral therapy treatment, he was remitted and returned to his duty. Triggered by new stress caused by unfavorable environmental factors (occupational environment), psychotic phenomenology appeared. After two years of psychiatric treatment, patient was evaluated unfit for MS. Conclusion. Early-age trauma and/or PTSD are predispositions for a comorbid psychotic disorder, while the diagnostic entity of psychotic subtype of PTSD requires further research. Evaluation of MS abilities in patients with psychotic disorder based on our clinical experience, will require a psychiatric treatment for at least two years, which is in accordance with a research conducted in the British Army.

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.

Dissociative subtype of post-traumatic stress disorder: preliminary results examining sleep architecture

Dissociative subtype of post-traumatic stress disorder: preliminary results examining sleep architecture

Personality-Based PTSD Subtypes in Young Adults.

The symptom presentation of Posttraumatic Stress Disorder (PTSD) varies widely between individuals, which can complicate both diagnosis and treatment. Personality may help to explain this variability, and personality-based subtypes of PTSD (Externalizing, Internalizing, Simple; Miller et al., 2003) have been identified for this purpose. Yet, empirical tests of these subtypes have been limited, focusing largely on older samples with combat trauma or other homogenous trauma types. Our study examined PTSD subtypes in two samples of young adults with heterogeneous trauma exposure using cluster analyses. We tested for subtype-based heterogeneity in traumatic response (i.e., PTSD symptomatology). Results revealed that, across the two samples, Externalizing (low conscientiousness, moderate neuroticism), Internalizing (low extraversion, moderate neuroticism), and Simple (low neuroticism) personality-based subtypes emerged, consistent with the existing literature. Subtype-based differences in PTSD symptom severity also were observed, with the Simple subtype generally exhibiting less severe PTSD symptomatology than Internalizing and Externalizing subtypes. However, the subtypes did not differ in terms in number or type (interpersonal versus non-interpersonal) of traumatic experiences. Findings support PTSD subtypes and their relevance for post-traumatic response, particularly PTSD severity, in young adults with a variety of trauma types.

Trauma Management Therapy and Prolonged Exposure Therapy for PTSD in an active duty sample: Design and methodology of a randomized clinical trial

Posttraumatic stress disorder (PTSD) resulting from military service is a common, yet often chronic condition. Treatment outcome often is attenuated by programs that are (a) lengthy in nature and (b) constricted in their target outcomes. These limitations leave much of the emotional and behavioral impairment that accompanies PTSD unaddressed and/or unassessed. Typical PTSD treatment programs are 3–4 months in length, which is challenging for the pace of the nation's military. In this investigation, we will compare two treatments, Trauma Management Therapy (TMT) and Prolonged Exposure (PE), both redesigned to address the needs of active duty personnel (300 participants at 3 military installations). Specifically, we will compare the TMT Intensive Outpatient Program (IOP; 3 weeks) to PE's compressed (2 week) format. Both interventions will be compared to a standard course of PE (12 weeks). In addition to PTSD symptomatology, outcome measurement includes other aspects of psychopathology as well as changes in social, occupational, and familial impairment. Potential negative outcomes of massed treatment, such as increased suicidal ideation or increased alcohol use, will be assessed, as will genetic predictors of PTSD subtype and treatment outcome. This study will inform the delivery of care for military-related PTSD and particularly the use of intensive or compressed treatments for active duty personnel.

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.

PTSD and its dissociative subtype through the lens of the insula: Anterior and posterior insula resting-state functional connectivity and its predictive validity using machine learning.

Individuals with post-traumatic stress disorder (PTSD) typically experience states of reliving and hypervigilance; however, the dissociative subtype of PTSD (PTSD+DS) presents with additional symptoms of depersonalization and derealization. Although the insula is critical to emotion processing, its association with these contrasting symptom profiles is yet to be fully delineated. Accordingly, we investigated insula subregion resting-state functional connectivity patterns among individuals with PTSD, PTSD+DS, and healthy controls. Using SPM12 and PRONTO software, we implemented a seed-based resting-state functional connectivity approach, along with multiclass Gaussian process classification machine learning, respectively, in order to evaluate unique patterns and the predictive validity of insula subregion connectivity among individuals with PTSD (n=84), PTSD+DS (n=49), and age-matched healthy controls (n=51). Ascompared to PTSD and PTSD+DS, healthy controls showed increased right anterior and posterior insula connectivity with frontal lobe structures. By contrast, PTSD showed increased bilateral posterior insula connectivity with subcortical structures, including the periaqueductal gray. Strikingly, ascompared to PTSD and controls, PTSD+DS showed increased bilateral anterior and posterior insula connectivity with posterior cortices, including the left lingual gyrus and the left precuneus. Moreover, machine learning analyses were able to classify PTSD, PTSD+DS, and controls using insula subregion connectivity patterns with 80.4% balanced accuracy (p < .01). These findings suggest a neurobiological distinction between PTSD and its dissociative subtype with regard to insula subregion functional connectivity patterns. Furthermore, machine learning algorithms were able to utilize insula resting-state connectivity patterns to discriminate between participant groups with high predictive accuracy.

Prevalence and clinical correlates of dissociative subtype of posttraumatic stress disorder at an outpatient trauma clinic in South Korea

ABSTRACT Background: Previous studies on of the dissociative subtype of posttraumatic stress disorder (d-PTSD) have relied on specialized statistical methods (i.e. profile or class analyses) for diagnosis than clinical rating available to clinicians. Objective: This study investigated the prevalence and covariates of d-PTSD diagnosed by a semi-structured interview in a cohort of outpatients with DSM-IV PTSD in a specialized trauma clinic in South Korea. Method: Data from 249 patients with civilian PTSD were examined, including demographics, clinical variables, Clinical Global Impression (CGI) Scale, and Clinician-Administered PTSD Scale (CAPS-IV). We defined d-PTSD as the presence of either depersonalization or derealization according to additional dissociative items of the CAPS. About one third (n = 82, 32.9%) of patients were designated as having d-PTSD. Results: Compared to the other patients with PTSD, those with d-PTSD were younger, had more severe PTSD symptoms, frequent interpersonal trauma, and a higher number of comorbid disorders. When these variables and their interactions were entered into a logistic regression model, younger age, severe PTSD symptoms and two or more comorbid conditions remained for the final model. We did not find a significant difference in improvement over the course of treatment between two groups. Conclusions: This study highlights the high prevalence of d-PTSD in a clinical population. Associated features of d-PTSD were similar to those reported in the Euro-American literature. Further studies are needed to better understand mechanisms and treatment options for d-PTSD.

Cardiac reactions to emotional words in adolescents and young adults with PTSD after child abuse.

Post-traumatic stress disorder (PTSD) is associated with alterations in cardiac reactivity to threat cues. Meta-analyses have summarized that adults with PTSD have increased heart rates in response to trauma-related stimuli. However, the opposite effect (i.e., cardiac hyporeactivity) has recently been reported in subgroups of PTSD patients. In children and adolescents with PTSD, reports of cardiac alterations are rare and ambiguous. So far, most studies in adolescents and young adults are restricted to victims of accidents, even though PTSD is highly prevalent in victims of child maltreatment. The present study aimed at investigating cardiac reactions in adolescents and young adults with PTSD after child abuse. Cardiac responses to standardized emotional words were studied in 39 adolescent and young adult PTSD patients after childhood sexual and/or physical abuse as compared to 39 healthy control subjects (age range: 15-20years). The experimental paradigm consisted of a passive reading task with neutral, positive, physically threatening, and socially threatening (swear) words. Results showed that cardiac reactions to negative stimuli, particularly physically threatening stimuli, were less pronounced in PTSD patients than in controls. Moreover, cardiac reactions in response to socially threatening words were less variable in the PTSD group. No differences between and within groups were present in reaction to neutral or positive stimuli. Findings suggest that a physiologically blunted subtype of PTSD may already manifest during adolescence and young adulthood. Moreover, the results of the present study emphasize the relevance of individual trauma history for physiological reactions.

The Dissociative Subtype of PTSD Interview (DSP-I): Development and Psychometric Properties

ABSTRACTThe inclusion of the dissociative subtype of post-traumatic stress disorder (PTSD-DS) in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM–5) reflects the importance of assessing PTSD-DS. We developed the Dissociative Subtype of PTSD Interview (DSP-I). This clinician-administered instrument assesses the presence and severity of PTSD-DS (i.e., symptoms of depersonalization or derealization) and contains a supplementary checklist that enables assessment and differentiation of other trauma-related dissociative symptoms (i.e., blanking out, emotional numbing, alterations in sensory perception, amnesia, and identity confusion). The psychometric properties were tested in 131 treatment-seeking individuals with PTSD and histories of multiple trauma, 17.6 % of whom met criteria for PTSD-DS in accordance with the DSP-I. The checklist was tested in 275 treatment-seeking individuals. Results showed the DSP-I to have high internal consistency, good convergent validity with PTSD-DS items of the CAPS-5, and good divergent validity with scales of somatization, anxiety and depression. The depersonalization and derealization scales were highly associated. Moreover, the DSP-I accounted for an additional variance in PTSD severity scores of 8% over and above the CAPS-5 and number of traumatic experiences. The dissociative experiences of the checklist were more strongly associated with scales of overall distress, somatization, depression, and anxiety than scales of depersonalization and derealization. In conclusion, the DSP-I appears to be a clinically relevant and psychometrically sound instrument that is valuable for use in clinical and research settings.

Tonic Immobility in PTSD: Exacerbation of Emotional Cardiac Defense Response.

Among defensive behaviors, tonic immobility (TI) is considered the last defensive resort when life is at extreme risk. Post-Traumatic Stress Disorder (PTSD) is the main psychiatric consequence resulting from exposure to traumatic events. Increasing evidence indicate an association between peritraumatic tonic immobilility and severity of PTSD. Cardiac defense response, a reactivity to perceived danger or threat, has been studied by recording heart rate changes that follows the presentation of an unpredictable intense auditory aversive stimulus. The aim of this study was to investigate potential distinctiveness in cardiac defense response among PTSD patients who presented – compared to those that did not – TI reaction in the laboratory setting. Patients (N = 17) completed the TI questionnaire for signs of immobility elicited by passive listening to their autobiographical trauma script. After a while, they were exposed to an intense white noise, while electrocardiogram was recorded. The heart rate during the 80 s after the noise, subtracted from baseline, was analyzed. Higher reports of TI to the trauma script were associated with stronger and sustained heart rate accelerations after the noise. The effects on cardiac defense response add to increasing evidence that some PTSD patients are prone to repeated re-experiences of TI, which may implicate in a potentially distinct pathophysiology and even a new PTSD subtype.

Autonomic responses to fear conditioning among women with PTSD and dissociation.

Individuals with posttraumatic stress disorder (PTSD) demonstrate alterations in autonomic responses to fear conditioning, such as exaggerated startle and poor fear inhibition. However, there is a paucity of research on fear conditioning among individuals with PTSD and dissociative symptoms, which represents 10-30% of those with PTSD. The current study used a fear-potentiated startle (FPS) conditioning paradigm to examine autonomic responses among women with PTSD and a range of dissociative symptoms. Participants included 39 women with PTSD and dissociation, and 53 women with PTSD with unknown levels of dissociation. The FPS paradigm consisted of conditioned stimuli associated and not associated with an aversive unconditioned stimulus. FPS response (eyeblink startle), electrocardiogram (ECG), and skin conductance response (SCR) were collected during the FPS paradigm. Compared to the PTSD-unknown dissociation sample, the PTSD-dissociation sample demonstrated significantly lower FPS during the last block of conditioning. Among the PTSD-dissociation sample, higher dissociation scores were associated with decreased FPS and SCR, and higher respiratory sinus arrhythmia (derived from ECG). Results suggest that autonomic responses to fear conditioning differ depending on the presence and severity of dissociative symptoms. Given that treatment response may differ depending on dissociative symptoms, it is important to understand the mechanisms that underlie different subtypes of PTSD and that may affect treatment response and outcome.

Psychometric Properties of the Dissociative Subtype of PTSD Scale: Replication and Extension in a Clinical Sample of Trauma-Exposed Veterans

The addition of the dissociative subtype of posttraumatic stress disorder (PTSD) to the DSM-5 has spurred investigation of its genetic, neurobiological, and treatment response correlates. In order to reliably assess the subtype, we developed the Dissociative Subtype of PTSD Scale (DSPS; Wolf et al., 2017), a 15-item index of dissociative features. Our initial investigation of the dichotomous DSPS lifetime items in a veteran epidemiological sample demonstrated its ability to identify the subtype, supported a three-factor measurement structure, distinguished the three subscales from the normal-range trait of absorption, and demonstrated the greater contribution of derealization and depersonalization symptoms relative to other dissociative symptomatology. In this study, we replicated and extended these findings by administering self-report and interview versions of the DSPS, and assessing personality and PTSD in a sample of 209 trauma-exposed veterans (83.73% male, 57.9% with probable current PTSD). Results replicated the three-factor structure using confirmatory factor analysis of current symptom severity interview items, and the identification of the dissociative subtype (via latent profile analysis). Associations with personality supported the discriminant validity of the DSPS and suggested the subtype was marked by tendencies towards odd and unusual cognitive experiences and low positive affect. Receiver operating characteristic curves identified diagnostic cut-points on the DSPS to inform subtype classification, which differed across the interview and self-report versions. Overall, the DSPS performed well in psychometric analyses, and results support the utility of the measure in identifying this important component of posttraumatic psychopathology.