Relationships between a Dissociative Subtype of PTSD and Clinical Characteristics in Patients with Substance Use Disorders

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

BACKGROUND

The 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.

METHODS

A 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.

RESULTS

A 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.

LIMITATIONS

The cross-sectional design, Chinese cultural background, online survey method and oversimple measurements were the limitations.

CONCLUSIONS

Our 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.

Turkish Adaptation of Dissociative Subtype of Post Traumatic Stress Disorder Scale

After the changes in DSM-5, dissociative subtype was added to post-traumatic stress disorder. That caused a necessity for a scale to measure the mentioned change. A scale named Dissociative Subtype of Post-Traumatic Stress Disorder (DSPS) was developed to measure this subtype and help the diagnosis. The purpose of this study is to adapt the Dissociative Subtype of Post-Traumatic Stress Disorder to Turkish and examine its reliability and validity. The Dissociative Subtype of PTSD (DSPS) was translated into Turkish. DSPS, Turkish forms of The Posttraumatic Diagnostic Scale and Dissociative Experiences Scale were sent to participants via Google Forms and data from 279 people aged 18-45 were analyzed. Reliability tests and factor analysis were conducted. Factor analysis showed that scale has good model fit scores and items were loaded to the factors the same as the original study. Scales internal consistency was examined, and a good score was obtained (α=.84). Fit index values of confirmatory factor analysis were found as χ2/df = 2.51, GFI=.90, RMSEA=.07, RMR=.02. As a result of the high reliability scores and sufficient model fit scores, this scale is considered as a dependable measure to evaluate the dissociative subtype of PTSD.

Women with PTSD and Substance Use Disorders in a Research Treatment Study: A Comparison of those with and without the Dissociative Subtype of PTSD

Significant differences in clinical features have been reported in women with substance use disorders (SUDs) between those with the dissociative subtype of posttraumatic stress disorder (D-PTSD) compared to those without, namely more severe trauma histories, PTSD symptoms, and general psychopathology. This presentation reports on a group of 88 women with PTSD and SUD taking part in a research treatment study. All women were assessed using the Clinician Administered PTSD Scale for DSM-5 (CAPS-5) and were categorized into those with (n = 23, 26%) and without (n = 65, 74%) D-PTSD. Assessments for SUDs were via the Multi-International Neuropsychiatric Inventory, Seventh Version (MINI-7). Compared to those without D-PTSD, those with D-PTSD had significantly higher CAPS-5 scores (50.5 ± 9.9 v. 39.6 ± 8.8), greater number of PTSD symptoms (16.4 ± 2.6 v. 14.2 ± 2.4), more alcohol use disorder (AUD) (65.2% v. 30.8%), and more non-cocaine stimulant use disorder (34.8% v. 12.3%). No significant differences were found for other SUDs. These women with SUDs and D-PTSD have higher degrees of PTSD severity as well as unique clinical presentations. Future research is needed to explore the significance of these findings for clinical assessment and treatment.

Prevalence, Clinical Features, and Psychological Characteristics of Dissociative Subtype of Posttraumatic Stress Disorder in Chinese Prisoners

This study aimed to examine prevalence, clinical symptoms, and psychological characteristics of D-PTSD in a sample of Chinese prisoners with probable PTSD. A total of 1458 male prisoners were recruited from a large prison in Guangdong, China. Participants completed self-administrated questionnaires that assessed PTSD and dissociative symptoms, psychopathology, emotion regulation, emotional expressivity, social pleasure, traumatic events, and social support. According to DSM-5 criteria, participants were classified into four groups: D-PTSD, PTSD only, derealization/depersonalization (DD) only, and neither. The proportions of D-PTSD, PTSD only, DD only and neither were 2.5%, 4.7%, 2.4%, and 92.2%, respectively. PTSD symptoms and emotion regulation difficulties were distinguishing for the four groups: PTSD symptoms declined gradually in the order of D-PTSD, PTSD only, DD only, and neither, while emotion regulation difficulties declined in an order from D-PTSD, DD only, and PTSD only to neither, all ps < .001. D-PTSD and DD only had higher depressive and dissociative symptoms than PTSD only and the neither groups, all ps < .001. D-PTSD also had more borderline personality symptoms, emotion regulation difficulties, and more negative emotional expressivity than PTSD only and DD only, all ps < .05. Logistic regressions indicated that D-PTSD reported lower social support compared to PTSD only (OR = 0.95, p < .01), DD only (OR = 0.96, p < .05) and neither (OR = 0.93, p < .001). D-PTSD is common in probable PTSD in prisoners and is associated with complex clinical presentations as well as emotional processing. Social support is an important protective factor of D-PTSD.

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.

Psychological risk factors that characterize acute stress disorder and trajectories of posttraumatic stress disorder after injury: a study using latent class analysis

Background

The course and different characteristics of acute and posttraumatic stress disorder (ASD, PTSD) in trauma populations are unclear.

Objective

The aims were to identify longitudinal trajectories of PTSD, to establish a risk profile for ASD and PTSD based on patients' sociodemographic, clinical, and psychological characteristics, and to study the effect of ASD and dissociation on PTSD during 12 months after trauma.

Method

Patients completed questionnaires after inclusion and at 3, 6, 9, and 12 months afterwards. Trajectories were identified using repeated measures latent class analysis (RMLCA). The risk profile was based on a ranking of importance of each characteristic using Cohen's d effect sizes and odds ratios. The impact of ASD and dissociation on PTSD was examined using logistic regression analyses.

Results

Altogether, 267 patients were included. The mean age was 54.0 (SD = 16.1) and 62% were men. The prevalence rate of ASD was approximately 21.7% at baseline, and 36.1% of trauma patients exhibited PTSD at 12 months after injury. Five trajectories were identified: (1) no PTSD symptoms, (2) mild, (3) moderate, (4) subclinical, and (5) severe PTSD symptoms. These trajectories seemed to remain stable over time. Compared with patients in other trajectories, patients with ASD and (subclinical) PTSD were younger and scored higher on anxiety, depressive symptoms, neuroticism, and trait anxiety. Regarding dissociation symptoms, inability to recall memories about the event was significantly more present than an altered sense of reality, (105 (40.7%) versus 56 (21.7%), p = .031), although that symptom had the strongest likelihood for PTSD. Patients with dissociation were significantly at risk for PTSD than patients without dissociation (OR = 4.82; 95%CI: 1.91-12.25).

Conclusions

Psychological factors characterized ASD and trajectories of PTSD during 12 months post-trauma. Healthcare providers who are aware of these findings could early identify patients at risk for ASD and PTSD and refer them for patient-centred interventions.

Exploring dissociation as a facilitator of suicide risk: A translational investigation using virtual reality

Research shows that suicidal behavior is not a result of a single cause or single event, but instead is an interaction of facilitators. One potential facilitator that needs further exploration is dissociation. Dissociation has been consistently linked to suicidal behavior, and theories have posited that dissociation increases the possibility of a suicidal act via intensified disconnect from the body. However, these theories do not indicate whether dissociation is a facilitator of suicide risk by increasing suicidal ideation and attempt behaviors. Additionally, unique considerations of working with suicidal individuals have caused suicide research to lag behind research where laboratory manipulation is possible. Virtual Reality (VR) technology is potentially a useful new translational approach to studying suicide causes. Undergraduate students (n = 145) completed a dissociation induction task and then decided whether to engage in a virtual suicide option. Results showed that those who reported higher dissociation scores also reported higher suicide risk and indicated that certain facets of dissociation (i.e., depersonalization and derealization) significantly predicted engaging in virtual suicide. Results indicate that dissociation should be considered as a factor in the assessment and treatment of suicide risk. Limitations include that this used an uncommon suicide attempt method (i.e., jumping), and engaging in VR suicide is not the same as engaging in actual suicide or suicidal behaviors. However, VR may recreate certain sensations and situations one might experience when engaging in a suicide attempt and thus should be considered assessing and treating suicide risk.

Improving care for SUD patients with complex trauma-relationships between childhood trauma, dissociation, and suicidal behavior in female patients with PTSD and SUD

BACKGROUND

Posttraumatic disorders are among the most frequent co-occurring diagnoses in patients with substance use disorders (SUD). Individuals with this dual diagnosis often present with special treatment needs, especially after childhood traumatic experiences (CT). Along with posttraumatic stress disorder (PTSD) and dissociative symptoms, suicidal behaviors belong to the clinical challenges in this group of patients and may influence the course and outcome of SUD treatment. Therefore, a better understanding of the relationships between different forms of CT, psychopathology and suicidal behaviors seems to be important to tailor adequate concepts of care.

MATERIALS AND METHODS

We examined 343 female patients with SUD and Posttraumatic stress disorder (PTSD). All patients completed the Childhood Trauma Questionnaire (CTQ), the Dissociative Experiences Scale-Taxon (DES-T) and the Structured Clinical Interview Axis I Disorders (SCID-I). To determine relationships between different symptoms with potential importance for concepts of treatment, we conducted analyses of moderated mediation for different models. We examined the direct and indirect effects of associations between the type of CT, dissociation and suicidal behavior, as well as the moderation effect of PTSD.

RESULTS

All participants met DSM-criteria for either full PTSD (75.2%) or subsyndromal PTSD (24.8%). Almost all (94.5%) received at least one substance dependence diagnosis and the remaining 5.5% met substance abuse criteria. Most participants (93.3%) reported at least one type of childhood trauma. In all models, dissociation was a risk factor for suicidal ideation (SI) and for suicide attempts (SA). In both, participants with subsyndromal PTSD and participants with full PTSD, dissociation mediated the relationship between childhood sexual abuse and SI as well as SA. Moreover, we report direct effects between different childhood traumas and SI and SA. Furthermore, emotional abuse was a significant predictor of dissociation.

DISCUSSION

In our sample of female patients with SUD and co-occurring PTSD, dissociation significantly increased suicidal behavior and served as a mediator of the relationship between childhood sexual abuse and suicidal behavior. Our findings underline the need to include interventions to address dissociative symptoms and other more complex consequences of childhood trauma into concepts of care for patients with SUD.

Dissociation as a Transdiagnostic Indicator of Self-Injurious Behavior and Suicide Attempts: A Focus on Posttraumatic Stress Disorder and Borderline Personality Disorder

Dissociative symptoms and suicidality are transdiagnostic features of posttraumatic stress disorder (PTSD) and borderline personality disorder (BPD). The primary objective of this study was to examine associations between dissociation (i.e., depersonalization and derealization) and suicidality (i.e., self-harm and suicide attempts) among individuals with PTSD and BPD. We analyzed data from the 2012-2013 National Epidemiologic Survey on Alcohol and Related Conditions (NESARC-III; N = 36,309). The Alcohol Use Disorder and Associated Disabilities Interview Schedule for DSM-5 was used to assess lifetime PTSD and BPD. Estimated rates of self-harm among individuals who endorsed dissociation were 15.5%-26.2% for those with PTSD and 13.7%-23.5% for those with BPD, and estimates of suicide attempts among individuals who endorsed dissociation were 34.5%-38.1% for those with PTSD and 28.3%-33.1% for those with BPD. Multiple logistic regressions were conducted to examine the associations between dissociation (derealization, depersonalization, and both) and both self-harm and suicide attempts among respondents with PTSD and BPD. The results indicated that dissociation was associated with self-harm and suicide attempts, especially among individuals with BPD, aORs = 1.39-2.66; however, this association may be driven in part by a third variable, such as other symptoms of PTSD or BPD (e.g., mood disturbance, PTSD or BPD symptom severity). These results may inform risk assessments and targeted interventions for vulnerable individuals with PTSD, BPD, or both aimed at mitigating the risk of self-harm and suicide.

Associations among betrayal trauma, dissociative posttraumatic stress symptoms, and substance use among women involved in the criminal legal system in three US cities

BACKGROUND

Betrayal trauma, as defined by (Freyd, 1996), refers to a subcategory of trauma characterized by a significant violation of trust surrounding interpersonal maltreatment (physical, sexual, or emotional). Previous research has shown that people with betrayal trauma histories experience greater dissociative symptoms of posttraumatic stress disorder and co-morbid substance use disorder symptoms. Women in the criminal legal system commonly have significant histories of betrayal trauma and related posttraumatic stress symptoms and substance use. However, no studies have specifically explored the impact of dissociative posttraumatic stress symptoms on substance use outcomes in this population. Additionally, no studies have explored whether betrayal trauma relates to nonfatal overdoses.

METHODS

This cross-sectional survey study of N = 508 women with criminal legal system involvement examined the indirect effects of betrayal trauma history on substance use outcomes through dissociative posttraumatic stress symptoms.

RESULTS

Multivariate analyses supported an indirect effect of betrayal trauma on substance use severity, daily substance use, and history of overdose, but not alcohol use severity, through dissociative symptoms.

CONCLUSIONS

Women in the criminal legal system with betrayal trauma and dissociative symptoms may be at risk for substance use and related outcomes (i.e., overdose). Future work is needed to examine whether targeting such symptoms may improve substance use treatment and prevention of serious outcomes in this population.

Clarifying the Relationship of Dissociative Experiences to Suicide Ideation and Attempts: A Multimethod Examination in Two Samples

Fears of pain, injury, and death may represent key barriers to acting on suicidal thoughts. Dissociation, which involves a disconnection from one's body, may reduce fears and sensations of pain associated with harming the body, in turn facilitating suicide attempts. This study examined whether dissociation differentiated individuals with a history of suicide attempts from those with a history of suicide ideation, and investigated whether other relevant constructs explain this relationship. Sample 1 included 754 undergraduates (M_age = 21, 79% female) who completed a battery of self-report measures. Sample 2 included 247 undergraduates (M_age = 19, 74% female) who completed a self-report measure of dissociation, a clinical interview regarding suicide history, and four counterbalanced behavioral pain tolerance tasks. In both samples, dissociation was elevated in lifetime attempters compared to ideators (d = 0.28; d = 0.46; ps = 0.01) and slightly elevated in lifetime ideators compared to nonsuicidal individuals (d = 0.19, p = .02; d = 0.24, p = .47), though this effect was non-significant in the latter sample. In Sample 1, dissociation no longer differentiated attempters from ideators after controlling for clinical covariates. In Sample 2, dissociation was unrelated to behavioral pain tolerance tasks, and these tasks did not account for the association between dissociation and attempts. Overall, dissociation differentiated individuals with a history of suicide attempts from those with ideation alone in both samples. Pain tolerance did not explain this association; instead, it is possible that the relationship of dissociation to suicide attempts is due to "third variables" associated with both phenomena, such as symptoms of borderline personality disorder or posttraumatic stress disorder.

Altered dynamic parahippocampus functional connectivity in patients with post-traumatic stress disorder

OBJECTIVES

This study investigated dynamic brain functional alterations in post-traumatic stress disorder (PTSD) patients with resting state functional magnetic resonance imaging.

METHODS

Degree centrality (DC) and seed-based functional connectivity (FC) analyses were conducted among typhoon survivours with (n = 27) and without PTSD (n = 33) and healthy controls (HC) (n = 30) to assess the intrinsic dysconnectivity pattern and network-level brain function.

RESULTS

Both the PTSD group and the trauma-exposed control (TEC) group had increased DC in the left parahippocampal gyrus relative to the HC group. More increased DC in the left parahippocampal gyrus was found in the PTSD group. Both traumatised groups exhibited decreased left parahippocampal gyrus dynamic FC with the bilateral middle frontal gyrus and superior frontal gyrus relative to the HC group. The Checklist-Civilian Version score was positively correlated with dynamic FC between the parahippocampal gyrus and left superior frontal gyrus but was negatively correlated with dynamic FC between the parahippocampal gyrus and right middle frontal gyrus.

CONCLUSIONS

Trauma exposure may lead to an altered dynamic FC in individuals with or without PTSD. An altered DC in the parahippocampal gyrus may be an important risk factor for PTSD development following trauma exposure. A more prominently increased DC in the parahippocampal gyrus might be a common trait in the PTSD group.

The relationship between dissociative symptoms and the medications used in the treatment of opioid use disorder

Opioid use disorder has long been associated with psychiatric symptoms, including dissociative experiences. Medications used to treat opioid use disorder can potentially impact dissociative symptoms, but the existing literature has not explored this. We examined the relationship between dissociative symptoms and opioid use disorder using the Dissociative Experiences Scale (DES). We studied subjects who were taking prescribed methadone, buprenorphine, or naltrexone for opioid use disorder. We gave the DES, the Patient Health Questionairre-9 (PHQ-9), and the PTSD Checklist for DSM-5 (PCL-5) with Criterion A to subjects in three substance use treatment facilities in Ohio. We conducted Analysis of Variance (ANOVA) and Spearman's Rank Correlations to examine associations between the variables and outcomes. We developed three separate multiple linear regression models. We included 116 participants in our exploratory and naturalistic study. The majority of participants were female (51.7%), white (89.5%), ≤ 40 years of age (64.7%), and taking buprenorphine (55%). The average DES score was 16.1 (standard deviation = 14.9) and we considered 80.9% to have low dissociation (score < 30). Approximately 55% (n = 64) of participants were taking prescribed buprenorphine. Approximately 27% (n = 32) were taking prescribed methadone and approximately 18% (n = 21) were taking prescribed naltrexone (oral or extended release). There was a significant association between opioid medication type and log dissociative symptoms (p = .01). Participants taking prescribed buprenorphine had higher mean log dissociation symptom scores (2.7) compared to those taking prescribed methadone (2.2) and prescribed naltrexone (2.1). Log dissociation symptom scores were significantly associated with last use of any opiates (rs = -0.21; p = .02) and time on medication (rs = -0.228; p = .01). Compared to those taking buprenorphine, those taking both methadone (β = -0.26; p = .01) and naltrexone (β = -0.27; p = .006) had significantly lower dissociation scores, controlling for the other variables in the model. Dissociation scores were positively correlated with depression scores (r = 0.45; p < .0001) and with PCL-5 scores (r = 0.51; p < .0001). Our study highlights the importance of diagnosing and monitoring dissociative symptoms in individuals who are taking prescribed medications for opioid use disorder, especially since dissociative symptoms can interfere with substance use treatment.

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.

Resolution of Dissociated Ego States Relieves Flashback-Related Symptoms in Combat-Related PTSD: A Brief Mindfulness Based Intervention

A novel understanding and therapeutic approach to the treatment of PTSD-related flashback triggers are described. Triggered responses are conceptualized as the result of latent dissociative structures of neural organization and psychodynamic functioning activated by current events. The dissociative structure - here described as a dissociated ego state (DES) - reflects a fracturing of executive functioning resulting in a delimited aspect of self that is not under cognitive control or subject to cognitive inhibition by the self of daily experience, and is the psychological construct behind intrusive PTSD symptoms. Use of a mindful attentional state permits regulated access to the DES (therapeutic engagement without risk of emotional dysregulation) so that dissociated cognitive resources can be recovered and the dissociated structure deactivated. This may relieve maladaptive responses and behaviors associated with the DES in a profound and durable way, without the need for exposure to or recovery of traumatic memories. Based on this understanding, a 9-step intervention is introduced with a case example of a Vietnam veteran suffering PTSD symptoms for 49 years with significant gains maintained at 21 months follow up. These findings demonstrate rapid and durable resolution of chronic PTSD symptoms through a mindfulness-based approach that focused on deactivation of dissociated ego states, in contrast to targeting trauma memories. If proven efficacious, this novel approach may result in reduced treatment costs and improved outcomes for veterans suffering with PTSD.

Women and substance use disorders in low- and middle-income countries: A call for advancing research equity in prevention and treatment

Although the prevalence of substance use disorders (SUDs) is higher among men, women with SUDs in low- and middle-income countries (LMICs) face unique challenges. Poverty and adversity, inequality of women, and disparities in access to treatment and prevention services exacerbate biological, psychological and social correlates of substance use disorders for women living in low-resource settings. Increasing the inclusion of women in research has long been a goal, though even high income countries struggle to achieve parity. In LMICs, women with SUDs are often neglected from global research due to underreporting and the disproportionate focus of global substance use research on men. We will discuss risk factors for SUDs that are particularly relevant for women residing in LMICs in order to gain insight into neglected areas of research and opportunities for prevention and treatment.

The dissociative subtype of PTSD in women with substance use disorders: Exploring symptom and exposure profiles

The dissociative subtype of posttraumatic stress disorder (PTSD) was officially introduced in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5). In accordance with this new classification, prior studies using Latent Class Analysis (LCA) empirically identified a subgroup of patients that were characterized by a high severity of dissociative symptoms. Despite the high prevalence of PTSD in patients with substance use disorders (SUD), however, no LCA studies on the dissociative subtype of PTSD exist in this population so far. Therefore, the current study aimed to identify subgroups of patients with different symptom and exposure profiles in patients with SUD and PTSD. It was assumed that one symptom and exposure profile could be identified that would be characterized by higher dissociative symptoms, higher additional psychopathology and a higher burden of childhood trauma, as compared to other subgroups. In N = 258 female patients with SUD and PTSD, clinical characteristics of dissociative symptoms, PTSD severity, borderline personality disorder (BPD), depression, childhood trauma and substance abuse were assessed. To identify symptom and exposure profiles, Latent Class Analysis was applied. A three-class solution indicated the best model fit to our data. One class was characterized by a high probability of dissociative symptoms (D-PTSD class), whereas the other two classes were characterized by lower probabilities of dissociative symptoms. The D-PTSD class encompassed 18.7% of the patients. In accordance with our hypothesis, the D-PTSD class showed higher probabilities of PTSD severity, borderline personality disorder symptoms, depressive symptoms, childhood emotional and sexual abuse, childhood emotional neglect, and drug abuse. Our results indicate that the dissociative subtype of PTSD could also be identified in a sample of female patients with SUD. Patients with SUD and PTSD characterized by the dissociative subtype showed more severe psychopathological symptoms than the remaining patients, indicating enhanced clinical needs for this vulnerable group.

Increased Inhibition of the Amygdala by the mPFC may Reflect a Resilience Factor in Post-traumatic Stress Disorder: A Resting-State fMRI Granger Causality Analysis

Purpose: To determine whether effective connectivity of the amygdala is altered in traumatized subjects with and without post-traumatic stress disorder (PTSD). Materials and Methods: Resting-state functional MRI data were obtained for 27 patients with typhoon-related PTSD, 33 trauma-exposed controls (TEC), and 30 healthy controls (HC). Effective connectivity of the bilateral amygdala was examined with Granger causality analysis and then compared between groups by conducting an analysis of variance. Results: Compared to the HC group, both the PTSD group and the TEC group showed increased effective connectivity from the amygdala to the medial prefrontal cortex (mPFC). The TEC group showed increased effective connectivity from the mPFC to the amygdala relative to the HC group. Compared to the TEC group, the PTSD group showed increased effective connectivity from the amygdala to the supplementary motor area (SMA), whereas decreased effective connectivity was detected from the SMA to the amygdala. Both the PTSD group and the TEC group showed decreased effective connectivity from the superior temporal gyrus (STG) to the amygdala relative to the HC group. Compared to the HC group, the TEC group showed increased effective connectivity from the amygdala to the dorsolateral prefrontal cortex (dlPFC), while both the PTSD group and the TEC group showed decreased effective connectivity from the dlPFC to the amygdala. The PTSD group showed decreased effective connectivity from the precuneus to the amygdala relative to both control groups, but increased effective connectivity from the amygdala to the precuneus relative to the HC group. Conclusion: Trauma leads to an increased down-top excitation from the amygdala to the mPFC and less regulation of the amygdala by the dlPFC. The results suggest that increased inhibition of the amygdala by the mPFC may reflect a resilience factor, and altered amygdala-SMA and amygdala-STG effective connectivity may reflect compensatory mechanisms of brain function. These data raise the possibility that insufficient inhibition of the amygdala by the mPFC might lead to PTSD in those who have been exposed to traumatic incidents, and may inform future therapeutic interventions.