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.

A - 73 The Impact of Posttraumatic Stress Disorder on Cognitive Health in 9/11 Responders: the Role of Sleep Disturbances

OBJECTIVE

PTSD is known to have a long-term impact on cognitive health, specifically executive dysfunction. However, most studies have not tested possible mechanisms underpinning this association. Sleep disturbances have emerged as a potential pathway between PTSD and cognitive functioning. This study aimed to investigate whether sleep disturbances account for the association between PTSD and executive dysfunction in trauma-exposed first responders.

METHOD

Participants consisted of 9/11 WTC responders (N = 452, mean age = 55.22, SD = 8.73, 89% male, 90% White). Data collection occurred across 3 time points, each 1 year apart. Measures included self-reported PTSD and insomnia symptoms, two weeks of Ecological Momentary Assessment of sleep duration and sleep quality, and the Trail Making Test part B. Due to high stability across 3 years, the present study focused on mean, trait-like variables. Analyses adjusted for demographics, BMI, and trauma exposure severity.

RESULT

PTSD was associated with Trail Making Test part B (r = 0.10, p = 0.03), as well as insomnia (r = 0.63, p < 0.00) and sleep quality (r = -0.45, p < 0.00), but not sleep duration. Mediation analyses revealed that sleep quality fully accounts for the significant association between PTSD and executive functioning (indirect effect β = 0.056, p = 0.041, 95% CI [0.009, 0.108]).

CONCLUSIONS

The current results highlight the important role that disturbances in sleep may have on cognitive health outcomes. Improving sleep, in the context of PTSD, could attenuate cognitive symptoms, and possibly protect against further decline. Future research conducted in the acute phase of trauma-exposure and PTSD is needed to clarify the directionality of these relationships, with longitudinal analyses that will allow form modeling cognitive decline.

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.

The Role of Personality in the Mental and Physical Health of World Trade Center Responders: Self- versus Informant-Reports

Personality is linked to important health outcomes, but most prior studies have relied on self-reports, making it possible that shared-method variance explains the associations. The present study examined self- versus informant-reports of personality and multi-method outcomes. World Trade Center (WTC) responders and informants, 283 pairs, completed five-factor model personality measures and multi-method assessments of stressful events, functioning, mental disorders, 9/11-related treatment costs, BMI, and daily activity across three years. Self-reports were uniquely related to stressful events and functioning. Both self-reports and informant-reports showed incremental validity over one another for mental disorder diagnoses and treatment costs. For objective outcomes daily activity and BMI, informant-reports showed incremental validity over self-reports, accounting for all self-report variance and more. The findings suggest that informant-reports of personality provide better validity for objective health outcomes, which has implications for understanding personality and its role in mental and physical health.

Investigating the molecular genetic, genomic, brain structural, and brain functional correlates of latent transdiagnostic dimensions of psychopathology across the lifespan: Protocol for a systematic review and meta-analysis of cross-sectional and longitudinal studies in the general population

BACKGROUND

Research using latent variable modelling has identified a superordinate general dimension of psychopathology, as well as several specific/lower-order transdiagnostic dimensions (e.g., internalising and externalising) within the meta-structure of psychiatric symptoms. These models can facilitate discovery in genetic and neuroscientific research by providing empirically derived psychiatric phenotypes, offering greater validity and reliability than traditional diagnostic categories. The prospective review outlined in this protocol aims to integrate and assess evidence from research investigating the biological correlates of general psychopathology and specific/lower-order transdiagnostic symptom dimensions. Cross-sectional and longitudinal studies investigating general population samples of any age group or developmental period will be included to capture evidence from across the lifespan.

METHODS AND ANALYSIS

MEDLINE, Embase, and PsycINFO databases will be systematically searched for relevant literature. The review will follow the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Eligibility criteria were designed to capture psychiatric genetic (i.e., molecular genetic and genomic) and neuroimaging (i.e., brain structural and brain functional) studies investigating latent transdiagnostic dimension(s) or structural model(s) of psychopathology across any age group. Studies which include or exclude participants based on clinical symptoms, disorders, or relevant risk factors (e.g., history of abuse, neglect, and trauma) will be excluded. Biometric genetic research (e.g., twin and family studies), candidate gene studies, neurophysiology studies, and other non-imaging based neuroscientific studies (e.g., post-mortem studies) will be excluded. Study quality and risk of bias will be assessed using the Joanna Briggs Checklist for Analytical Cross-Sectional Studies, the Joanna Briggs Checklist for Cohort Studies, and the Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) system. Meta-analysis will be conducted if sufficient data is available.

DISCUSSION

This protocol outlines the first systematic review to examine evidence from studies investigating the latent structure and underlying biology of psychopathology and to characterise these relationships developmentally across the lifespan. The prospective review will cover a broad range of statistical techniques and models used to investigate latent transdiagnostic dimensions of psychopathology, as well as a numerous genetic and neuroscientific methods.

SYSTEMATIC REVIEW REGISTRATION

[https://www.crd.york.ac.uk/prospero/], identifier[CRD42021262717].

Artificial intelligence language predictors of two-year trauma-related outcomes

BACKGROUND

Recent research on artificial intelligence has demonstrated that natural language can be used to provide valid indicators of psychopathology. The present study examined artificial intelligence-based language predictors (ALPs) of seven trauma-related mental and physical health outcomes in responders to the World Trade Center disaster.

METHODS

The responders (N = 174, M_age = 55.4 years) provided daily voicemail updates over 14 days. Algorithms developed using machine learning in large social media discovery samples were applied to the voicemail transcriptions to derive ALP scores for several risk factors (depressivity, anxiousness, anger proneness, stress, and personality). Responders also completed self-report assessments of these risk factors at baseline and trauma-related mental and physical health outcomes at two-year follow-up (including symptoms of depression, posttraumatic stress disorder, sleep disturbance, respiratory problems, and GERD).

RESULTS

Voicemail ALPs were significantly associated with a majority of the trauma-related outcomes at two-year follow-up, over and above corresponding baseline self-reports. ALPs showed significant convergence with corresponding self-report scales, but also considerable uniqueness from each other and from self-report scales.

LIMITATIONS

The study has a relatively short follow-up period relative to trauma occurrence and a limited sample size.

CONCLUSIONS

This study shows evidence that ALPs may provide a novel, objective, and clinically useful approach to forecasting, and may in the future help to identify individuals at risk for negative health outcomes.

Mapping the transcriptomics landscape of post-traumatic stress disorder symptom dimensions in World Trade Center responders

Gene expression has provided promising insights into the pathophysiology of post-traumatic stress disorder (PTSD); however, specific regulatory transcriptomic mechanisms remain unknown. The present study addressed this limitation by performing transcriptome-wide RNA-Seq of whole-blood samples from 226 World Trade Center responders. The investigation focused on differential expression (DE) at the gene, isoform, and for the first time, alternative splicing (AS) levels associated with the symptoms of PTSD: total burden, re-experiencing, avoidance, numbing, and hyperarousal subdimensions. These symptoms were associated with 76, 1, 48, 15, and 49 DE genes, respectively (FDR < 0.05). Moreover, they were associated with 103, 11, 0, 43, and 32 AS events. Avoidance differed the most from other dimensions with respect to DE genes and AS events. Gene set enrichment analysis (GSEA) identified pathways involved in inflammatory and metabolic processes, which may have implications in the treatment of PTSD. Overall, the findings shed a novel light on the wide range of transcriptomic alterations associated with PTSD at the gene and AS levels. The results of DE analysis associated with PTSD subdimensions highlights the importance of studying PTSD symptom heterogeneity.

Positive and negative affect in the daily life of world trade center responders with PTSD: An ecological momentary assessment study

OBJECTIVE

The ability to experience positive affect (PA) has clinical and quality of life implications, particularly in vulnerable populations such as trauma-exposed disaster responders. Low PA is included in the diagnostic criteria for posttraumatic stress disorder (PTSD), however evidence for PA reduction in PTSD has been mixed. In contrast, negative affect (NA) has consistently been found to be elevated among individuals with PTSD. Multiday, ecological momentary assessment (EMA) can provide more ecologically valid evidence about experiences of affect; however, no such studies have been conducted in traumatized individuals with PTSD to date.

METHOD

World Trade Center (WTC) responders (N = 202) oversampled for the presence of PTSD were recruited from the WTC Health Program. Participants were administrated the Structured Clinical Interview for DSM-IV and the PTSD Checklist for DSM-5 at baseline, then completed EMA surveys of affect four times a day over seven consecutive days.

RESULTS

Participants with current PTSD (19.3% of the sample) showed significantly higher levels of daily NA compared with those without PTSD. However, there was no group difference in daily PA, nor was PA associated with a dimensional measure of PTSD.

CONCLUSION

Results suggest that for chronic PTSD among disaster responders, positive emotions are not inhibited across daily living. Such findings add to evidence suggesting that PA reduction may not be diagnostically relevant to PTSD, whereas NA remains an important target for therapeutic interventions. Moreover, results show that WTC responders can experience and benefit from positive emotion, even if they continue to have PTSD symptoms. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

Enhancing Psychosis-Spectrum Nosology Through an International Data Sharing Initiative

The latent structure of schizotypy and psychosis-spectrum symptoms remains poorly understood. Furthermore, molecular genetic substrates are poorly defined, largely due to the substantial resources required to collect rich phenotypic data across diverse populations. Sample sizes of phenotypic studies are often insufficient for advanced structural equation modeling approaches. In the last 50 years, efforts in both psychiatry and psychological science have moved toward (1) a dimensional model of psychopathology (eg, the current Hierarchical Taxonomy of Psychopathology [HiTOP] initiative), (2) an integration of methods and measures across traits and units of analysis (eg, the RDoC initiative), and (3) powerful, impactful study designs maximizing sample size to detect subtle genomic variation relating to complex traits (the Psychiatric Genomics Consortium [PGC]). These movements are important to the future study of the psychosis spectrum, and to resolving heterogeneity with respect to instrument and population. The International Consortium of Schizotypy Research is composed of over 40 laboratories in 12 countries, and to date, members have compiled a body of schizotypy- and psychosis-related phenotype data from more than 30000 individuals. It has become apparent that compiling data into a protected, relational database and crowdsourcing analytic and data science expertise will result in significant enhancement of current research on the structure and biological substrates of the psychosis spectrum. The authors present a data-sharing infrastructure similar to that of the PGC, and a resource-sharing infrastructure similar to that of HiTOP. This report details the rationale and benefits of the phenotypic data collective and presents an open invitation for participation.

Proton pump inhibitors and the risk of severe cognitive impairment: The role of posttraumatic stress disorder

Introduction

Proton pump inhibitors (PPIs), a common treatment for gastroesophageal reflux disease (GERD), were recently associated with increased risk of dementia. However, severe or chronic stress including, for example, posttraumatic stress disorder (PTSD) was not accounted for. This study examined whether PPI use was associated with severe cognitive impairment (SCI) and whether PTSD explained this association in a cohort of World Trade Center (WTC) responders.

Method

A prospective cohort study of 3779 WTC responders attending a university-based monitoring and treatment program. Prescriptions for PPIs and SCI determined using the Montreal Cognitive Assessment were the focus of the analysis.

Results

Overall, 1451 (38.4%) responders were dispensed PPIs, and 83 (2.2%) had SCI. Bivariable analyses revealed significant associations between being-dispensed PPIs in relation to SCI. After adjusting for PTSD, major depressive disorder, WTC exposures, age, and sex, being-dispensed PPIs were significantly associated with odds of SCI (adjusted odds ratio = 1.67 95% confidence interval = 1.054–2.643).

Conclusions

Being-dispensed PPIs were associated with SCI in this analysis of WTC responders. Results suggest that clinicians treating GERD seek to both understand patients' mental health history and monitor cognitive functioning when designing treatment routines. Overall, results confirmed that this is an important area of investigation with potential direct clinical implications.

Power corrupts co-operation: cognitive and motivational effects in a double EEG paradigm

This study investigated the effect of interpersonal power on co-operative performance. We used a paired electro-encephalogram paradigm: pairs of participants performed an attention task, followed by feedback indicating monetary loss or gain on every trial. Participants were randomly allocated to the power-holder, subordinate or neutral group by creating different levels of control over how a joint monetary reward would be allocated. We found that power was associated with reduced behavioural accuracy. Event-related potential analysis showed that power-holders devoted less motivational resources to their targets than did subordinates or neutrals, but did not differ at the level of early conflict detection. Their feedback potential results showed a greater expectation of rewards but reduced subjective magnitude attributed to losses. Subordinates, on the other hand, were asymmetrically sensitive to power-holders' targets. They expected fewer rewards, but attributed greater significance to losses. Our study shows that power corrupts balanced co-operation with subordinates.

Concurrent repetition enhancement and suppression responses in extrastriate visual cortex

Visual cortical responses are usually attenuated by repetition, a phenomenon known as repetition suppression (RS). Here, we use multivoxel pattern analyses of functional magnetic resonance imaging (fMRI) data to show that RS co-occurs with the converse phenomenon (repetition enhancement, RE) in a single cortical region. We presented human volunteers with short sequences of repeated faces and measured brain activity using fMRI. In an independently defined face-responsive extrastriate region, the response of each voxel to repetition (RS vs. RE) was consistent across scanner runs, and multivoxel patterns for both RS and RE voxels were stable. Moreover, RS and RE voxels responded to repetition with dissociable latencies and exhibited different patterns of connectivity with lower and higher visual regions. Computational simulations demonstrated that these effects must be due to differences in repetition sensitivity, and not feature selectivity. These findings establish that 2 classes of repetition responses coexist within 1 visual region and support models acknowledging this distinction, such as predictive coding models where perception requires the computation of both predictions (which are enhanced by repetition) and prediction errors (which are suppressed by repetition).