A historical review of trauma-related diagnoses to reconsider the heterogeneity of PTSD

Are There Differences Among Evidence-Based Psychotherapies for Treating Different DSM-5 PTSD Symptom Clusters? A Systematic Review and Meta-analysis of Controlled Clinical Trials

ABSTRACT

Posttraumatic stress disorder (PTSD) is a heterogeneous disease defined by four Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5) symptom clusters: reexperiencing, avoidance, negative alterations in cognitions and mood, and hyperarousal. There are effective evidence-based psychotherapies (EBPs) for PTSD. However, given the variety of PTSD clinical presentations, we conducted the first meta-analysis investigating whether DSM-5 PTSD symptom clusters show different responses to EBPs. We systematically reviewed the literature for controlled clinical trials in five databases, performed a meta-analysis, and evaluated the methodological quality of the studies. We screened 633 studies and included seven. Three showed high risk, two showed some concerns, and one showed a low risk of bias. The symptom clusters do not seem to respond differently to EBPs (SMD cluster B: -0.40; 95% confidence interval [CI], -0.87 to 0.08; cluster C: -0.49; 95% CI, -0.90 to -0.08; cluster D: -0.44; 95% CI, -0.94 to 0.05; cluster E: -0.54; 95% CI, -1.07 to -0.0), even when analyzed by the therapeutic focuses. The findings dovetail nicely with the network theory of PTSD symptom, as although it is a heterogeneous disorder, the EBPs seem to promote a kind of cascade of symptom improvement.

Increasing Value and Reducing Waste of Research on Neurofeedback Effects in Post-traumatic Stress Disorder: A State-of-the-Art-Review

Post-Traumatic Stress Disorder (PTSD) is often considered challenging to treat due to factors that contribute to its complexity. In the last decade, more attention has been paid to non-pharmacological or non-psychological therapies for PTSD, including neurofeedback (NFB). NFB is a promising non-invasive technique targeting specific brainwave patterns associated with psychiatric symptomatology. By learning to regulate brain activity in a closed-loop paradigm, individuals can improve their functionality while reducing symptom severity. However, owing to its lax regulation and heterogeneous legal status across different countries, the degree to which it has scientific support as a psychiatric treatment remains controversial. In this state-of-the-art review, we searched PubMed, Cochrane Central, Web of Science, Scopus, and MEDLINE and identified meta-analyses and systematic reviews exploring the efficacy of NFB for PTSD. We included seven systematic reviews, out of which three included meta-analyses (32 studies and 669 participants) that targeted NFB as an intervention while addressing a single condition-PTSD. We used the MeaSurement Tool to Assess systematic Reviews (AMSTAR) 2 and the criteria described by Cristea and Naudet (Behav Res Therapy 123:103479, 2019, https://doi.org/10.1016/j.brat.2019.103479 ) to identify sources of research waste and increasing value in biomedical research. The seven assessed reviews had an overall extremely poor quality score (5 critically low, one low, one moderate, and none high) and multiple sources of waste while opening opportunities for increasing value in the NFB literature. Our research shows that it remains unclear whether NFB training is significantly beneficial in treating PTSD. The quality of the investigated literature is low and maintains a persistent uncertainty over numerous points, which are highly important for deciding whether an intervention has clinical efficacy. Just as importantly, none of the reviews we appraised explored the statistical power, referred to open data of the included studies, or adjusted their pooled effect sizes for publication bias and risk of bias. Based on the obtained results, we identified some recurrent sources of waste (such as a lack of research decisions based on sound questions or using an appropriate methodology in a fully transparent, unbiased, and useable manner) and proposed some directions for increasing value (homogeneity and consensus) in designing and reporting research on NFB interventions in PTSD.

Epistasis in neurotransmitter receptors linked to posttraumatic stress disorder and major depressive disorder comorbidity in traumatized Chinese

Background

Posttraumatic stress disorder (PTSD) and major depressive disorder (MDD) comorbidity occurs through exposure to trauma with genetic susceptibility. Neuropeptide-Y (NPY) and dopamine are neurotransmitters associated with anxiety and stress-related psychiatry through receptors. We attempted to explore the genetic association between two neurotransmitter receptor systems and the PTSD-MDD comorbidity.

Methods

Four groups were identified using latent profile analysis (LPA) to examine the patterns of PTSD and MDD comorbidity among survivors exposed to earthquake-related trauma: low symptoms, predominantly depression, predominantly PTSD, and PTSD-MDD comorbidity. NPY2R (rs4425326), NPY5R (rs11724320), DRD2 (rs1079597), and DRD3 (rs6280) were genotyped from 1,140 Chinese participants exposed to earthquake-related trauma. Main, gene-environment interaction (G × E), and gene-gene interaction (G × G) effects for low symptoms, predominantly depression, and predominantly PTSD were tested using a multinomial logistic model with PTSD-MDD comorbidity as a reference.

Results

The results demonstrated that compared to PTSD-MDD comorbidity, epistasis (G × G) NPY2R-DRD2 (rs4425326 × rs1079597) affects low symptoms (β = -0.66, OR = 0.52 [95% CI: 0.32-0.84], p = 0.008, pperm = 0.008) and predominantly PTSD (β = -0.56, OR = 0.57 [95% CI: 0.34-0.97], p = 0.037, pperm = 0.039), while NPY2R-DRD3 (rs4425326 × rs6280) impacts low symptoms (β = 0.82, OR = 2.27 [95% CI: 1.26-4.10], p = 0.006, pperm = 0.005) and predominantly depression (β = 1.08, R = 2.95 [95% CI: 1.55-5.62], p = 0.001, pperm = 0.001). The two G × G effects are independent.

Conclusion

NPY and dopamine receptor genes are related to the genetic etiology of PTSD-MDD comorbidity, whose specific mechanisms can be studied at multiple levels.

Distinctively different human neurobiological responses after trauma exposure and implications for posttraumatic stress disorder subtyping

Trauma elicits various adaptive and maladaptive responses among all exposed people. There may be distinctively different patterns of adaptation/maladaptation or types according to neurobiological predisposition. The present study aims to dissect the heterogeneity of posttraumatic conditions in order to identify clinically meaningful subtypes in recently traumatized individuals and evaluate their neurobiological correlates and long-term prognosis. We implemented a data-driven classification approach in both discovery (n = 480) and replication (n = 220) datasets of trauma-exposed and trauma-unexposed individuals based on the clinical data across a wide range of assessments. Subtype-specific patterns of functional connectivity in higher-order cortical networks, longitudinal clinical outcomes, and changes in functional connectivity were also evaluated. We identified four distinct and replicable subtypes for trauma-exposed individuals according to posttraumatic stress symptoms. Each subtype was distinct in clinical characteristics, brain functional organization, and long-term trajectories for posttraumatic symptoms. These findings help enhance current understanding of mechanisms underlying the human-specific heterogeneous responses to trauma. Furthermore, this study contributes data towards the development of improved interventions, including targeting of subtype-specific characteristics, for trauma-exposed individuals and those with PTSD.

Latent class analysis of post-traumatic stress disorder symptoms following exposure to Hurricane Ike

BACKGROUND

There is substantial heterogeneity in how people react to potentially traumatic events (PTEs). Although some literature has explored this heterogeneity, there are only a few studies identifying factors associated with it within the disaster literature.

OBJECTIVE

The current investigation identified latent classes of post-traumatic stress disorder (PTSD) symptoms and differences between these classes after exposure to Hurricane Ike.

METHODS

Adults living in Galveston and Chambers County, Texas, (n = 658) completed a battery of measures during an interview conducted two to five months after Hurricane Ike. Latent class analysis (LCA) was performed to identify latent classes of PTSD symptoms. Additionally, gender, age, racial or ethnic minority status, depression severity, anxiety severity, quality of life, perceived need for services, and disaster exposure were examined to explore class differences.

RESULTS

LCA supported a 3-class model with low (n = 407, 61.9%), moderate (n = 191, 29.0%), and high PTSD symptoms (n = 60, 9.1%). Women appeared most at-risk for a moderate-severity presentation as compared to a low-severity presentation. Further, racial or ethnic minority groups appeared most at-risk for a high-severity presentation as compared to a moderate-severity presentation. Overall, the high symptom class had the poorest well-being, the most perceived need for services, and the highest exposure to the disaster, followed by the moderate symptom class, and finally the low symptom class.

CONCLUSIONS

PTSD symptom classes appeared to be differentiated primarily by overall severity as well as important psychological, contextual, and demographic dimensions.

Unity or Anarchy? A Historical Search for the Psychological Consequences of Psychotrauma

The field of traumatic stress is often referred to as being in a state of controversy and lack of continuity. Throughout history, disputes repeatedly centered on defining the psychological consequences of severe adverse events and on their causes. Even to this day this is current. To understand these controversies, an extensive historical literature review is presented of how mental consequences of trauma have been described in history, of the circumstances in which this took place, and of the disputes that have influenced the conceptualization of these mental responses. We found psychotrauma always being surrounded by controversy. Significant heterogeneity in symptom expression has been described over the centuries to this day. Some symptoms appeared steadily over many decades, but often each time period showed its own core symptoms. At syndrome level, we found an acute condition, one with longer duration, and a complex condition. Also here, definitions varied over the decades. Finally, causes have always been debated, such as biological, psychological, socio-economic, cultural, political, or legal. To better reflect the described ongoing variation in symptomatology, a more flexible diagnostic approach is proposed with a combination of both staging and subtyping that offers room for a more flexible, symptom-oriented, and personalized perspective.

Post-traumatic stress disorder: a psychiatric disorder requiring urgent attention

Post-traumatic stress disorder (PTSD) is a severe and heterogenous psychiatric disorder that was first defined as a mental disorder in 1980. Currently, the Diagnostic and Statistical Manual of Mental Disorders Fifth Edition (DSM-5) and the International Classification of Diseases 11th Edition (ICD-11) offer the most widely accepted diagnostic guidelines for PTSD. In both diagnostic categories, experiencing a traumatic event (TE) is the necessary criterion for diagnosing PTSD. The TEs described in the DSM-5 include actual or threatened death, serious injury, sexual violence, and other extreme stressors, either directly or indirectly. More than 70% of adults worldwide are exposed to a TE at least once in their lifetime, and approximately 10% of individuals develop PTSD after experiencing a TE. The important features of PTSD are intrusion or re-experiencing fear memories, pervasive sense of threat, active avoidance, hyperarousal symptoms, and negative alterations of cognition and mood. Individuals with PTSD have high comorbidities with other psychiatric diseases, including major depressive disorder, generalized anxiety disorder, and substance use disorder. Multiple lines of evidence suggest that the pathophysiology of PTSD is complex, involving abnormal neural circuits, molecular mechanisms, and genetic mechanisms. A combination of both psychotherapy and pharmacotherapy is used to treat PTSD, but has limited efficacy in patients with refractory PTSD. Because of the high prevalence, heavy burden, and limited treatments, PTSD is a psychiatric disorder that requires urgent attention. In this review, we summarize and discuss the diagnosis, prevalence, TEs, pathophysiology, and treatments of PTSD and draw attention to its prevention.

TINY IN SIZE, BIG IN IMPACT: EXTRACELLULAR VESICLES AS MODULATORS OF MOOD, ANXIETY AND NEURODEVELOPMENTAL DISORDERS

Extracellular Vesicles (EVs) are tiny vesicles used by cells as means of cellular communication, through which the function and state of a given cell can be changed. A body of evidence has suggested that EVs could be culprits in the development and progression of various types of diseases, including neurodegenerative diseases such as Multiple Sclerosis (MS) and Alzheimer's Disease (AD). Unsurprisingly, EVs have also been implicate in mood, anxiety and neurodevelopmental disorders, such as Major Depressive Disorder (MDD), anxiety disorder and Autism-Spectrum Disorder (ASD), respectively. Here, we review the state-of-art regarding the roles of EVs in the aforementioned diseases and focus on the mechanisms by which they can cause and worsen disease. Harnessing the knowledge of EVs is not only important to deliver different cargos to cells in a specific manner to treat these diseases, but also to establish reliable disease biomarkers, which will aid in the early disease diagnosis and treatment, increasing the chance of successful treatment.

PTSD: Past, present and future implications for China

There has been a long history since human beings began to realize the existence of post-traumatic symptoms. Posttraumatic stress disorder (PTSD), a diagnostic category adopted in 1980 in the Diagnostic and Statistical Manual of Mental Disorders-Ⅲ, described typical clusters of psychiatric symptoms occurring after traumatic events. Abundant researches have helped deepen the understanding of PTSD in terms of epidemiological features, biological mechanisms, and treatment options. The prevalence of PTSD in general population ranged from 6.4% to 7.8% and was significantly higher among groups who underwent major public traumatic events. There has been a long way in the studies of animal models and genetic characteristics of PTSD. However, the high comorbidity with other stress-related psychiatric disorders and complexity in the pathogenesis of PTSD hindered the effort to find specific biological targets for PTSD. Neuroimage was widely used to elucidate the underlying neurophysiological mechanisms of PTSD. Functional MRI studies have showed that PTSD was linked to medial prefrontal cortex, anterior cingulate cortex and sub-cortical structures like amygdala and hippocampus, and to explore the functional connectivity among these brain areas which might reveal the possible neurobiological mechanism related to PTSD symptoms. For now, cognitive behavior therapy-based psychotherapy, including combination with adjunctive medication, showed evident treatment effects on PTSD. The emergence of more effective PTSD pharmacotherapies awaits novel biomarkers from further fundamental research. Several natural disasters and emergencies have inevitably increased the possibility of suffering from PTSD in the last two decades, making it critical to strengthen PTSD research in China. To boost PTSD study in China, the following suggestions might be helpful: (1) establishing a national psychological trauma recover project, and (2) exploring the mechanisms of PTSD with joint effort and strengthening the indigenized treatment of PTSD.

Oxytocin receptor variant rs53576 genotype is associated with dysphoric arousal symptoms of DSM-5 posttraumatic stress disorder in Chinese earthquake survivors

PURPOSE

Evidence suggests that the oxytocin receptor (OXTR) gene may be involved in the psychopathology of posttraumatic stress disorder (PTSD). This study aimed to investigate the effects of OXTR rs53576 genotype on PTSD symptoms introduced in the Diagnostic and Statistical Manual, Fifth Edition (DSM-5).

METHODS

This study was a cross-sectional study conducted among 1140 adults who had personally experienced the Wenchuan earthquake. PTSD symptoms were measured with the PTSD checklist for DSM-5. A custom-by-design 2 × 48-Plex SNPscan^TM Kit were used to determine the OXTR rs53576. Multiple regression models were used to analyze the independent and interactive effects of OXTR rs53576 genotype and earthquake exposure on the severity of total PTSD symptoms and different dimensions of PTSD symptoms.

RESULTS

The results revealed that the rs53576 genotype could significantly predict PTSD symptoms (β = 0.055, p = 0.045). Further analysis showed that the rs53576 genotype was only significantly associated with dysphoric arousal symptoms of PTSD (β = 0.080, p = 0.005). The rs53576 genotype × earthquake exposure interaction had no significant effect on different symptom clusters (p > 0.05).

CONCLUSION

This study showed that the rs53576 genotype was only associated with the dysphoric arousal symptoms but not with other symptom clusters of PTSD. These findings support the role of the OXTR on the psychopathology of PTSD and help us to understand the genetic basis of PTSD.

Posttraumatic Stress Disorder and Neuroprogression in Women Following Sexual Assault: Protocol for a Randomized Clinical Trial Evaluating Allostatic Load and Aging Process Acceleration

BACKGROUND

Posttraumatic stress disorder (PTSD) is a prevalent, chronic, and severe disorder related to traumatic events. Women are disproportionately affected by PTSD than men and are more at risk in the occurrence of sexual assault victimization. Estimates suggest that 50% of women develop PTSD following sexual assault and successful clinical management can be challenging. Growing evidence has implicated neural, immune, and endocrine alterations underpinning PTSD, but only few studies have assessed the evolution of acute PTSD in women.

OBJECTIVE

This study aims to measure whether the onset of PTSD is associated with accelerated aging in women following sexual assault. We hypothesize that the increase of allostatic load caused by PTSD leads to neuroprogression. We will implement a randomized clinical trial to compare responses to treatment with either interpersonal psychotherapy adapted for PTSD (IPT-PTSD) or the selective serotonin reuptake inhibitor sertraline.

METHODS

We will include women between 18 and 45 years of age, who experienced sexual assault from 1 to 6 months before the initial evaluation, and present with a Diagnostic and Statistical Manual of Mental Disorders, fifth edition (DSM-5) diagnosis of PTSD. Baseline evaluation will comprise clinical and psychometric assessments, structural and functional magnetic resonance imaging, neuropsychological testing, polysomnography, evaluation of immune and endocrine parameters, and genetic analyses. Age-matched female healthy controls will be included and subjected to the same evaluation. Patients will be randomized for treatment in 1 of the 2 arms of the study for 14 weeks; follow-up will continue until 1 year after inclusion via treatment as usual. The researchers will collect clinical and laboratory data during periodic clinical assessments up to 1-year follow-up.

RESULTS

Data collection started in early 2016 and will be completed by the end of the first semester of 2020. Analyses will be performed soon afterward, followed by the elaboration of several articles. Articles will be submitted in early 2021. This research project has obtained a grant from the Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP 2014/12559-5).

CONCLUSIONS

We expect to provide insight into the consequences of recent sexual assault exposure in women by investigating the degree of neuroprogression developing from an early stage of PTSD. We also expect to provide important evidence on the efficacy of a non-exposure psychotherapy (IPT-PTSD) to mitigate PTSD symptoms in recently sexually assaulted women. Further, we aim to obtain evidence on how treatment outcomes are associated with neuroprogression measures.

TRIAL REGISTRATION

Brazilian Clinical Trials Registry RBR-3z474z; http://www.ensaiosclinicos.gov.br/rg/RBR-3z474z/.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/19162.

Psychological therapies for post-traumatic stress disorder in adults: systematic review and meta-analysis

Background: Psychological therapies are the recommended first-line treatment for post-traumatic stress disorder (PTSD). Previous systematic reviews have grouped theoretically similar interventions to determine differences between broadly distinct approaches. Consequently, we know little regarding the relative efficacy of the specific manualized therapies commonly applied to the treatment of PTSD. Objective: To determine the effect sizes of manualized therapies for PTSD. Methods: We undertook a systematic review following Cochrane Collaboration guidelines. A pre-determined definition of clinical importance was applied to the results and the quality of evidence was appraised using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach. Results: 114 randomized-controlled trials (RCTs) of 8171 participants were included. There was robust evidence that the therapies broadly defined as CBT with a trauma focus (CBT-T), as well as Eye Movement Desensitization and Reprocessing (EMDR), had a clinically important effect. The manualized CBT-Ts with the strongest evidence of effect were Cognitive Processing Therapy (CPT); Cognitive Therapy (CT); and Prolonged Exposure (PE). There was also some evidence supporting CBT without a trauma focus; group CBT with a trauma focus; guided internet-based CBT; and Present Centred Therapy (PCT). There was emerging evidence for a number of other therapies. Conclusions: A recent increase in RCTs of psychological therapies for PTSD, results in a more confident recommendation of CBT-T and EMDR as the first-line treatments. Among the CBT-Ts considered by the review CPT, CT and PE should be the treatments of choice. The findings should guide evidence informed shared decision-making between patient and clinician.

Dropout from psychological therapies for post-traumatic stress disorder (PTSD) in adults: systematic review and meta-analysis

Background: Despite the established efficacy of psychological therapies for post-traumatic stress disorder (PTSD) there has been little systematic exploration of dropout rates. Objective: To ascertain rates of dropout across different modalities of psychological therapy for PTSD and to explore potential sources of heterogeneity. Method: A systematic review of dropout rates from randomized controlled trials (RCTs) of psychological therapies was conducted. The pooled rate of dropout from psychological therapies was estimated and reasons for heterogeneity explored using meta-regression. Results:: The pooled rate of dropout from RCTs of psychological therapies for PTSD was 16% (95% CI 14-18%). There was evidence of substantial heterogeneity across studies. We found evidence that psychological therapies with a trauma-focus were significantly associated with greater dropout. There was no evidence of greater dropout from therapies delivered in a group format; from studies that recruited participants from clinical services rather than via advertisements; that included only military personnel/veterans; that were limited to participants traumatized by sexual traumas; that included a higher proportion of female participants; or from studies with a lower proportion of participants who were university educated. Conclusions: Dropout rates from recommended psychological therapies for PTSD are high and this appears to be particularly true of interventions with a trauma focus. There is a need to further explore the reasons for dropout and to look at ways of increasing treatment retention.

Internet-delivered cognitive behavioural therapy for post-traumatic stress disorder: systematic review and meta-analysis

OBJECTIVE

To determine whether Internet-delivered cognitive behavioural therapy (i-CBT) is an effective treatment for those who meet diagnostic criteria for post-traumatic stress disorder (PTSD).

METHOD

A systematic review was undertaken according to Cochrane Collaboration Guidelines. The primary outcome measures were reduction in PTSD symptoms and drop-out. Categorical outcomes were meta-analysed as risk ratios (RRs) and continuous outcomes as mean differences (MDs) or standardised mean differences (SMDs).

RESULTS

Ten studies with 720 participants were included. Evidence showed that i-CBT may be associated with a clinically important reduction in post-treatment PTSD symptoms compared with wait list (SMD -0.60, 95% confidence interval -0.97 to -0.24; N = 560); however, only three studies reported follow-up data, and there was no evidence to support the maintenance of symptom improvement at follow-up of 3-6 months. There was no evidence of a difference in PTSD symptoms between i-CBT and Internet-delivered non-CBT post-treatment. There was evidence of greater treatment effect from trauma-focused i-CBT than i-CBT without a trauma focus, as well as evidence that treatment effect was increased by the provision of guidance.

CONCLUSIONS

While the review found some beneficial effects of i-CBT for PTSD post-treatment, the quality of the evidence was very low because of the small number of included trials and there was insufficient evidence to support the maintenance of improvement at follow-up of 3-6 months. Further work is required to establish non-inferiority to current first-line interventions; to determine long-term efficacy; to explore mechanisms of effect; and to establish optimal levels of guidance.

Distinct Profiles of Cell-Free MicroRNAs in Plasma of Veterans with Post-Traumatic Stress Disorder

Dysregulation of circulating microRNAs (miRNAs) in body fluids has been reported in psychiatric disorders such as schizophrenia, bipolar disorder, major depressive disorder, and post-traumatic stress disorder (PTSD). Recent studies of various diseases showed that extracellular vesicles (EV) in body fluids can provide different spectra of circulating miRNAs and disease-associated signatures from whole fluid or EV-depleted fraction. However, the association of miRNAs in EVs to PTSD has not been studied. In this study, we performed a comprehensive profiling of miRNAs in whole plasma, extracellular vesicles (EV) and EV-depleted plasma (EVD) samples collected from combat veterans with PTSD and matched controls by utilizing a next-generation sequencing (NGS) platform. In total, 520 circulating miRNAs were quantified from 24 male Iraq and Afghanistan combat veterans with (n = 12) and without (n = 12) PTSD. The overall miRNA profiles in whole plasma, EV and EVD fractions were different and miRNAs affected by PTSD were also distinct in each sample type. The concentration changes of miR-203a-3p in EV and miR-339-5p in EVD were confirmed in an independent validation cohort that consisted of 20 veterans (10 with and 10 without PTSD) using qPCR. The target genes of these two miRNAs were involved in signaling pathways and comorbid conditions associated with PTSD (e.g., neurotransmitter systems such as dopaminergic and serotonergic signaling, inflammatory response, and cardiovascular diseases). Our findings suggest that PTSD may have different impacts on miRNAs encapsulated in vesicles and outside of vesicles. Further studies using larger samples are needed to evaluate the utility of these miRNAs as diagnostic biomarkers for PTSD.

Genomics of posttraumatic stress disorder in veterans: Methods and rationale for Veterans Affairs Cooperative Study #575B

OBJECTIVES

Heritability in the risk for developing posttraumatic stress disorder (PTSD) has been established, but most genome-wide association studies (GWASs) of PTSD involve relatively small sample sizes and limited identification of associated genetic loci. This report describes the methodology of a Veterans Affairs (VA) Cooperative Studies Program GWAS of PTSD among combat-exposed U.S. veterans.

METHODS

Probable cases (with PTSD) and probable controls (without PTSD) were identified from among veterans enrolled in the VA Million Veteran Program (MVP) with an algorithm developed using questionnaire responses and electronic health record information. This algorithm, based on a statistical model, relied on medical chart reviews as a reference standard and was refined using telephone interviews. Subsequently, to evaluate the impact of probabilistic phenotyping on statistical power, the threshold probability for case-control selection was varied in simulations.

RESULTS

As of September 2018, >695,000 veterans have enrolled in MVP. For current analyses, genotyping data were available for >353,000 participants, including >83,000 combat-exposed veterans. A threshold probability of 0.7 for case and control designation yielded an interim >16,000 cases and >33,000 controls.

CONCLUSIONS

A formal methodological approach was used to identify cases and controls for subsequent GWAS analyses to identify genetic risk loci for PTSD.

Reward Ameliorates Posttraumatic Stress Disorder-Related Impairment in Sustained Attention

Background

Posttraumatic stress disorder is associated with impairments in sustained attention, a fundamental cognitive process important for a variety of social and occupational tasks. To date, however, the precise nature of these impairments and the posttraumatic stress disorder symptoms associated with them have not been well understood.

Methods

Using a well-characterized sample of returning United States military OEF/OIF/OND Veterans who varied in posttraumatic stress disorder symptoms, we employed a validated sustained attention paradigm designed to probe fluctuations across two attentional states characterized by prior research, including a peak state termed “in the zone” and a less efficient, more error-prone state termed “out of the zone.” Rewarded and nonrewarded conditions were employed to examine whether motivating strong task performance could ameliorate sustained attention deficits. Analyses examined associations between attentional state, availability of reward, and posttraumatic stress disorder symptoms.

Results

Results indicated that, consistent with prior findings, higher levels of posttraumatic stress disorder symptoms were broadly associated with impaired task performance. This impairment was driven largely by performance deficits during individuals' optimal (“in the zone”) attentional state, and follow-up analyses indicated that the performance deficit was primarily associated with anhedonia and emotional numbing symptoms. However, the deficit was partially ameliorated when better performance was rewarded.

Conclusion

Our results provide a more complex understanding of the sustained attention deficits associated with posttraumatic stress disorder and suggest that external incentives may help to enhance sustained attention performance for affected individuals.

Sex Differences in the Physiological Response to Ethanol of Rat Basolateral Amygdala Neurons Following Single-Prolonged Stress

Females are more likely to develop post-traumatic stress disorder (PTSD) than males. Also, symptoms of PTSD frequently precede alcohol abuse in females. Stressful, threat-related stimuli are evaluated by the amygdala, which is critical for establishing the emotional salience of environmental stimuli. Ethanol and stress have been shown to modify amygdala excitability, but effects of acute ethanol on neurons of the basolateral amygdala (BLA) in both males and females exposed to stress is unknown. The purpose of this study is to determine stress-induced changes in membrane properties of BLA neurons and to determine how ethanol modulates these changes in male and female rats. Whole-cell recordings were obtained from BLA neurons of both male and female rats exposed to single-prolonged stress (SPS). Neuronal excitability, quantified as the number of action potentials, was determined in current clamp mode by applying a series of depolarizing current steps. Hyperpolarization-activated current (I_h) was elicited in voltage clamp. Excitability and I_h amplitude were determined before and during the superfusion of ethanol (EtOH; 30 mM) in BLA neurons from SPS-treated male and female rats. SPS alone did not alter the firing properties of BLA neurons from either males or females. However, following SPS, BLA neurons from males and females respond differently to ethanol. Superfusion of EtOH (30 mM) inhibited spike firing in BLA neurons from rats exposed to SPS, and EtOH-induced inhibition was greater in females than in males exposed to stress. Also, EtOH (30 mM) selectively decreased I_h amplitude in BLA neurons from SPS-treated male rats from 171 ± 46 pA in (pre-EtOH) control to 53 ± 51 pA in the presence of EtOH (30 mM). EtOH did not reduce I_h in BLA neurons from SPS-treated females. Together, these suggest important sex differences in the physiological responses to EtOH in stress disorders such as PTSD, that have high comorbidity with alcohol use disorders.

PTSD Latent Classes and Class Transitions Predicted by Distress and Fear Disorders in Disaster-Exposed Adolescents

This study aimed to determine the population-based typologies of posttraumatic stress disorder (PTSD) symptomatology, the longitudinal patterns of transitions across these typologies, and the predictive effects of distress and fear disorder symptoms on these transitions in a frequently referred but scantly studied population of traumatized youth. A sample of 1,278 Chinese adolescents (54.0% girls) with a mean age of 13.4 years (SD = 0.8, range = 12-16) completed 2-wave surveys 2.5 and 3.5 years after a major disaster. Psychopathological symptoms were assessed with the UCLA PTSD Reaction Index for DSM-IV, the Depression Self-Rating Scale for Children, and the Screen for Child Anxiety Related Emotional Disorders. Latent class analyses identified 4 classes characterized by high, reexperiencing/hypervigilance, dysphoria, and low symptoms, respectively at each time point. Latent transition analyses revealed relatively high levels of temporal stability within low symptom and dysphoria classes but relatively high probabilities of migration from re-experiencing/hypervigilance and high symptom classes into lower symptom classes. Multinomial logistic regression analyses found that some of the between-class movements during the year were predicted by baseline distress or fear disorders. This study provides an initial depiction of both quantitative and qualitative changes in youth's long-term PTSD symptom patterns over time and gives a further elucidation of other forms of posttrauma psychopathology's impacts on PTSD course. These findings carry implications for ongoing evaluation and adjustable intervention individually tailored to youth's PTSD manifestations and comorbidities in the long-term disaster aftermath.

Post-traumatic stress symptom clusters in acute whiplash associated disorder and their prediction of chronic pain-related disability

Two symptom clusters were generated comprising specific (intrusion/avoidance cluster) and nonspecific (hyperarousal/numbing cluster) post-traumatic stress disorder symptoms. The nonspecific post-traumatic stress disorder symptoms cluster better predicted chronic pain-related disability.

Introduction:

The presence of post-traumatic stress disorder (PTSD) symptoms has been found to be associated with an increased risk of persisting neck pain and disability in motor vehicle crash (MVC) survivors with whiplash injuries. The findings are mixed as to which PTSD symptom(s) best predicts recovery in this population.

Objectives:

The aims were (1) to explore the factor structure of the Post-traumatic Stress Diagnostic Scale (PDS) in a sample of acute whiplash-injured individuals following a MVC and (2) to identify the PTSD-symptom clusters that best predict long-term neck pain-related disability in this population as measured by the Neck Pain Disability Index (NDI).

Methods:

A sample (N = 146) of whiplash-injured individuals completed the NDI and the PDS at baseline (<1 month) and at 6 months follow-up.

Results:

Principal component analyses generated 2 symptom clusters: re-experiencing/avoidance and hyperarousal/numbing. Nine trauma-related PTSD symptoms loaded exclusively on the re-experiencing/avoidance cluster and 7 nonspecific PTSD symptoms loaded exclusively on the hyperarousal/numbing cluster. One PTSD symptom (ie, inability to recall an important aspect of the trauma) had no salient loading on either clusters. Structural equation modelling analysis indicated that there was a significant positive relationship between the hyperarousal/numbing symptom cluster and long-term neck pain-related disability, while no significant relationship was found between the re-experiencing/avoidance symptom cluster and long-term neck pain-related disability.

Conclusion:

Given that only the hyperarousal/numbing symptom cluster predicted long-term neck pain-related disability, this finding may have implications in terms of diagnosis, assessment, and management of the psychological impact of whiplash-injured individuals following a MVC.

Patterns of DSM-5 posttraumatic stress disorder and depression symptoms in an epidemiological sample of Chinese earthquake survivors: A latent profile analysis

BACKGROUND

Posttraumatic stress disorder (PTSD) and depression are highly comorbid in association with serious clinical consequences. Nevertheless, to date, no study using latent class or latent profile analysis (LCA/LPA) has examined patterns of co-occurring PTSD and depression symptoms among natural disaster survivors, nor has the distinctiveness of DSM-5 PTSD and depression symptoms been clarified in the aftermath of trauma. This study was primarily aimed at filling these gaps.

METHODS

LPA was used to examine self-reported PTSD and depression symptoms in an epidemiological sample of 1196 Chinese earthquake survivors.

RESULTS

A 4-class solution characterized by low symptoms (53.9%), predominantly depression (18.2%), predominantly PTSD (18.9%) and combined PTSD-depression (9.0%) patterns fit the data best. Demographic characteristics and earthquake-related exposures were specifically or consistently associated with the non-parallel profiles varying in physical health impairment.

LIMITATIONS

A sample exposed to specific traumatic events was assessed by self-report measures.

CONCLUSIONS

The distinctiveness of DSM-5 PTSD and depression symptoms following an earthquake suggests that PTSD and depression may be independent sequelae of psychological trauma rather than a manifestation of a single form of psychopathology. The current findings support the distinction between PTSD and depression constructs, and highlight the need for identifications of natural disaster survivors at high risk for PTSD and/or depression, and interventions individually tailored to one's symptom presentations.