Dissecting the heterogeneity of posttraumatic stress disorder: differences in polygenic risk, stress exposures, and course of PTSD subtypes

An examination of the potential core symptoms of posttraumatic stress disorder: What is integral after removing general psychopathology & distress?

Many confirmatory factor analyses (CFA) have examined the structure of posttraumatic stress disorder (PTSD) with some suggesting increased complexity (i.e., 6+ factors), while others suggesting a more refined structure (i.e., 2-factors). These competing PTSD structures may be due to conflation of non-trauma specific symptoms that have been added overtime. However, none of these studies examined if all symptoms being examined are specific to PTSD or potentially more related to general distress and psychopathology. The current study re-evaluated the structure of PTSD using bifactor exploratory factor analysis (EFA) to identify the construct's core symptoms. Data for EFA models were taken from a sample of Veterans (N = 694) attending outpatient therapy for PTSD and were cross-validated using CFA in a sample of 297 Veterans attending residential treatment. Clinician Administered PTSD Scale for DSM-5 (CAPS-5) at pre-treatment was used across sample. Factor analyses resulted in a 2-factor, bifactor model comprised of eight total items. Model fit was robust, RMSEA = 0 [0.000, 0.036]; robust CFI = 1; robust TLI = 1.017. The bifactor analytic approach captured what might be the core structure of PTSD, which were pathognomonic symptoms of PTSD (Factor one). A distinct second factor related to depression was also found. In identifying this structure, the model eliminates redundancies and lesser performing items and differentiates depressive reactions as potentially distinct and separate. Overall, these findings may assist in future research of PTSD by determining the unique elements of the construct within a veteran sample versus associated features, general psychological distress, and comorbid psychopathology.

Genome-wide association analyses identify 95 risk loci and provide insights into the neurobiology of post-traumatic stress disorder

Post-traumatic stress disorder (PTSD) genetics are characterized by lower discoverability than most other psychiatric disorders. The contribution to biological understanding from previous genetic studies has thus been limited. We performed a multi-ancestry meta-analysis of genome-wide association studies across 1,222,882 individuals of European ancestry (137,136 cases) and 58,051 admixed individuals with African and Native American ancestry (13,624 cases). We identified 95 genome-wide significant loci (80 new). Convergent multi-omic approaches identified 43 potential causal genes, broadly classified as neurotransmitter and ion channel synaptic modulators (for example, GRIA1, GRM8 and CACNA1E), developmental, axon guidance and transcription factors (for example, FOXP2, EFNA5 and DCC), synaptic structure and function genes (for example, PCLO, NCAM1 and PDE4B) and endocrine or immune regulators (for example, ESR1, TRAF3 and TANK). Additional top genes influence stress, immune, fear and threat-related processes, previously hypothesized to underlie PTSD neurobiology. These findings strengthen our understanding of neurobiological systems relevant to PTSD pathophysiology, while also opening new areas for investigation.

Patterns of posttraumatic stress symptoms, their predictors, and comorbid mental health symptoms in traumatized Arabic-speaking people: A latent class analysis

Many people from the Middle East and North Africa (MENA) have experienced traumatic events due to human rights abuses, violence, and conflict in the region, with potential psychological consequences including symptoms of posttraumatic stress and comorbid mental health problems. Yet, little is known about how different posttraumatic stress symptoms unfold in Arabic-speaking people who have experienced diverse traumatic events. This study examined latent classes based on posttraumatic stress symptoms, differences across classes concerning comorbid mental health symptoms and quality of life, and several predictors, including sociodemographic characteristics, social support, and trauma-related characteristics. Participants were 5,140 traumatized Arabic-speaking individuals who had registered for an online intervention. Latent class analysis was conducted to identify distinct classes based on DSM-5 posttraumatic stress symptoms. Multinomial logistic regression was used to analyze predictors of class membership. Differences between classes in severity of posttraumatic stress, depressive, anxiety, and somatoform symptoms, as well as quality of life were examined. Five different latent classes were identified: a general high posttraumatic stress symptom class (43.8%), a high posttraumatic stress symptom-low avoidance class (12.8%), a mixed posttraumatic stress symptom class (20.9%), a high dysphoric-low reexperiencing/avoidance class (14%), and a general low posttraumatic stress symptom class (8.4%). The classes differed in severity of posttraumatic stress, depressive, anxiety and somatoform symptoms, and quality of life. Consistent significant predictors of class membership were gender, social support, cumulative trauma exposure, sexual violence and direct exposure during the most distressing trauma, as well as time since the most distressing trauma. Distinct symptom classes with quantitative and qualitative differences can emerge following exposure to trauma among help-seeking Arabic-speaking people from the MENA region, with gender, social support, and trauma-related characteristics predicting symptom presentation. The results have implications for identifying distressed people and enhancing interventions based on an individual's symptom presentation.

Discovery of 95 PTSD loci provides insight into genetic architecture and neurobiology of trauma and stress-related disorders

Posttraumatic stress disorder (PTSD) genetics are characterized by lower discoverability than most other psychiatric disorders. The contribution to biological understanding from previous genetic studies has thus been limited. We performed a multi-ancestry meta-analysis of genome-wide association studies across 1,222,882 individuals of European ancestry (137,136 cases) and 58,051 admixed individuals with African and Native American ancestry (13,624 cases). We identified 95 genome-wide significant loci (80 novel). Convergent multi-omic approaches identified 43 potential causal genes, broadly classified as neurotransmitter and ion channel synaptic modulators (e.g., GRIA1, GRM8, CACNA1E ), developmental, axon guidance, and transcription factors (e.g., FOXP2, EFNA5, DCC ), synaptic structure and function genes (e.g., PCLO, NCAM1, PDE4B ), and endocrine or immune regulators (e.g., ESR1, TRAF3, TANK ). Additional top genes influence stress, immune, fear, and threat-related processes, previously hypothesized to underlie PTSD neurobiology. These findings strengthen our understanding of neurobiological systems relevant to PTSD pathophysiology, while also opening new areas for investigation.

Latent polydrug use patterns and the provision of injection initiation assistance among people who inject drugs in three North American settings

INTRODUCTION

We sought to identify latent profiles of polysubstance use patterns among people who inject drugs in three distinct North American settings, and then determine whether profile membership was associated with providing injection initiation assistance to injection-naïve persons.

METHODS

Cross-sectional data from three linked cohorts in Vancouver, Canada; Tijuana, Mexico; and San Diego, USA were used to conduct separate latent profile analyses based on recent (i.e., past 6 months) injection and non-injection drug use frequency. We then assessed the association between polysubstance use patterns and recent injection initiation assistance provision using logistic regression analyses.

RESULTS

A 6-class model for Vancouver participants, a 4-class model for Tijuana participants and a 4-class model for San Diego participants were selected based on statistical indices of fit and interpretability. In all settings, at least one profile included high-frequency polysubstance use of crystal methamphetamine and heroin. In Vancouver, several profiles were associated with a greater likelihood of providing recent injection initiation assistance compared to the referent profile (low-frequency use of all drugs) in unadjusted and adjusted analyses, however, the inclusion of latent profile membership in the multivariable model did not significantly improve model fit.

DISCUSSION AND CONCLUSIONS

We identified commonalities and differences in polysubstance use patterns among people who inject drugs in three settings disproportionately impacted by injection drug use. Our results also suggest that other factors may be of greater priority when tailoring interventions to reduce the incidence of injection initiation. These findings can aid in efforts to identify and support specific higher-risk subpopulations of people who inject drugs.

Heterogeneity of resilience and the curvilinear relationship between childhood trauma and resilience among people with schizophrenia

Background

As a group with a high incidence of childhood trauma, the differential characteristics of resilience in schizophrenia and its relationship with childhood trauma are still unclear.

Methods

A total of 626 individuals diagnosed with schizophrenia were selected from four psychiatric hospitals in northern China. Childhood trauma and resilience were measured using the Childhood Trauma Questionnaire-short form (CTQ-SF) and Connor-Davidson Resilience Scale (CD-RISC), respectively. Latent profile analysis (LPA) was used to identify the potential classes of resilience. A generalized additive mixed model (GAMM) and restricted cubic spline (RCS) was used to explore and determine the shape of the relationship between childhood trauma and resilience.

Results

Model fits of LPA showed three heterogeneous classes of resilience: moderate resilience levels (n = 312; 49.06%); high resilience levels (n = 171; 26.89%) and low resilience levels (n = 153; 24.06%). Resilience scores fluctuated depending on amount of exposure to childhood trauma. The GAMM results verified the non-linear relationship between resilience and childhood trauma, with an estimated degree of freedom higher than 1 (4.573) and p = 0.003. RCS fitted for ordinary least square (OLS) regression models determined a smooth continuous cubic curve of resilience across childhood trauma levels, and the two turning points of the curve line were 41.04 and 54.74 for childhood trauma.

Discussion

Our findings confirm the people-specific differences in the level of resilience in schizophrenia and describe the cubic curvilinear relationship between childhood trauma and resilience, which provides data support for mechanistic research and intervention in related fields.

Quetiapine Treatment for Post-traumatic Stress Disorder: A Systematic Review of the Literature

Paroxetine and Sertraline are the only medications approved in posttraumatic stress disorder (PTSD). However, about 60% of traumatized patients fail to show an adequate clinical response. Second generation antipsychotics are recommended as second-line monotherapy or third-line augmentation strategies and quetiapine appears as one of the most used and promising agents. Up to date, no reviews assessed the efficacy of quetiapine in the treatment of PTSD. We aimed to assess the effectiveness and general safety of quetiapine on PTSD. A systematic review was conducted following Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) and Cochrane guidelines, selecting studies that evaluated the efficacy of quetiapine on global or specific PTSD symptomatology. Ten studies (n = 894) were considered eligible for qualitative synthesis: one case report, one case series, one prospective cohort study, 3 open-label trials, 3 retrospective studies, one randomized controlled trial. Quetiapine was effective on global PTSD symptomatology assessed in 6 studies as well as on re-experiencing (4/4 studies), avoidance (4/3 studies) and hyperarousal (4/4 studies), flashbacks (2/2 studies), depressive (4/4 studies), anxiety (1/1 studies), psychotic (3/3 studies), insomnia (4/5 studies), nightmares (3/3 studies) specific symptoms and PTSD domains. Sedation was among the most frequently observed adverse effects and the main cause of drug discontinuation. Preliminary findings support the efficacy of quetiapine in ameliorating symptoms relative to PTSD and its overall safety. However, quetiapine use in PTSD cannot be recommended yet as studies mainly rely on open-label, retrospective studies or case series.

Toward staging differentiation for posttraumatic stress disorder treatment

OBJECTIVES

Several medical and psychiatric disorders have stage-based treatment decision-making methods. However, international treatment guidelines for posttraumatic stress disorder (PTSD) fail to give specific treatment recommendations based on chronicity or stage of the disorder. There is convincing evidence of a finite range of PTSD symptom trajectories, implying that different phenotypes of the disorder can be distinguished, which are highly relevant for a staging typology of PTSD.

METHODS

State-of-the-art review building on prior work on staging models in other disorders as a mapping tool to identify and synthesize toward PTSD.

RESULTS

We propose a four-stage model of PTSD ranging from stage 0: trauma-exposed asymptomatic but at risk to stage 4: severe unremitting illness of increasing chronicity. We favor a symptom description in various chronological characteristics based on neurobiological markers, information processing systems, stress reactivity, and consciousness dimensions. We also advocate for a separate phenomenology of treatment resistance since this can yield treatment recommendations.

CONCLUSION

A staging perspective in the field of PTSD is highly needed. This can facilitate the selection of interventions that are proportionate to patients' current needs and risk of illness progression and can also contribute to an efficient framework to organize biomarker data and guide service delivery. Therefore, we propose that a neurobiologically driven trajectory-based typology of PTSD can help deduct several treatment recommendations leading to a more personalized and refined grid to strategize, plan and evaluate treatment interventions.

Transdiagnostic biomarker approaches to mental health disorders: Consideration of symptom complexity, comorbidity and context

Depression is a multifaceted disorder characterized by heterogeneous symptom profiles and high rates of comorbidity with other commonly occurring mental illnesses. Considering the burden of mental health disorders and the lack of efficacy of available treatments, there is a need for biomarkers to predict tailored or personalized treatments. However, identifying reliable biomarkers for complex mental illnesses, such as depression, anxiety and PTSD, has been challenging, likely owing to the heterogeneity, comorbidity and differences in experiences and histories of individuals. For these reasons, taking a transdiagnostic approach, which identifies biomarkers that map onto shared symptoms/constructs across disorders could be most effective for informing personalized or precision medicine approaches in psychiatry. Transdiagnostic features of anxiety, depression and anhedonia have been examined in relation to brain activity and connectivity patterns. Neuroendocrine and inflammatory markers, which are altered in depression and other comorbid illness, such as post-traumatic stress disorder (PTSD), might be useful in differentiating transdiagnostic symptom profiles as well as treatment responses. Ultimately, biomarker research that looks beyond diagnostic categories and embraces the complexity of individuals' lives and experiences might be more effective in moving towards precision medicine in psychiatry.