Identifying PTSD symptom typologies: A latent class analysis

Distressing memories: A continuum from wellness to PTSD

BACKGROUND

Exposure to traumatic events is a frequent source of distress, provoking isolated symptoms such as distressing memories (DM) to full-blown post-traumatic stress disorder (PTSD). We aimed to assess the continuum theory using DM as an isolated symptom, and to examine trauma consequences in a exposed to traumatic events.

METHODS

Using data from the National Epidemiologic Study of Alcohol and Related Conditions III, we assessed the prevalence of DM in a trauma exposed sample, and examined their sociodemographic and lifetime psychiatric correlates, comparing three groups: (i) controls (no DM, no PTSD); (ii) participants with isolated DM without PTSD; (iii) participants with PTSD. We estimated the sensitivity and specificity of DM for PTSD diagnosis.

RESULTS

In our sample of 17,505 participants exposed to trauma, 13 % had PTSD and 42 % had DM without PTSD. The sensitivity of DM for the diagnosis of PTSD was 95.14 %, specificity was 51.91 %. Participants with DM and those with PTSD shared the same socio-demographic correlates. Participants with DM reported more lifetime psychiatric disorders (mood disorders - mainly depressive disorders and bipolar type 1 disorder; anxiety disorders - mainly social anxiety disorder, substance use disorders - mainly opioid use disorder and cannabis disorder; eating disorders - mainly binge eating disorder; personality disorders - mainly borderline personality disorder- and suicidality) than controls, but less than participants with PTSD.

CONCLUSION

DM represent an intermediate state between well-being and post-traumatic stress disorder; DM is also associated with other psychiatric disorders. It should be considered as a transdiagnostic psychiatric symptom useful for clinicians in identifying psychiatric vulnerability.

Differences in intestinal bacteria in traumatic injury survivors with and without probable posttraumatic stress disorder

BACKGROUND

Posttraumatic stress disorder (PTSD) is a common consequence of traumatic injury, yet certain biological factors contributing to PTSD are poorly understood. The gut microbiome may influence mental health outcomes, but its role in heterogeneous PTSD presentations requires elucidation.

METHODS

Bacterial composition was examined in adults 2-4 years post-trauma with probable PTSD (n = 24) versus trauma-exposed controls without probable PTSD (n = 24). 16S rRNA sequencing and bioinformatic tools assessed microbial diversity and abundance. Relationships between taxa and PTSD symptom clusters were evaluated.

RESULTS

No differences were found in overall microbial community structure between groups. The probable PTSD group exhibited significantly reduced Actinobacteriota and increased Verrucomicrobiota phylum abundance compared to controls. Specific taxa showed notable inverse associations with negative mood/cognition versus hyperarousal symptoms. Prevotella and Ruminococcaceae were negatively associated with negative mood but positively associated with hyperarousal.

CONCLUSIONS

Results demonstrate microbial signatures of probable PTSD subtypes, highlighting the microbiome as a potential mediator of heterogeneous trauma psychopathology. Definition of PTSD microbial correlates provides a foundation for personalized psychobiotic interventions targeting predominant symptom profiles.

Identifying post-traumatic stress symptom typologies in clinical and non-clinical healthcare staff: a latent profile analysis

Background: There has been growing concern regarding increasing levels of post-traumatic stress (PTS) symptoms experienced by healthcare workers (HCW) in the UK, particularly following the COVID-19 pandemic.Objectives: PTS symptom typologies have been investigated in other adult populations using person-centred latent variable approaches, revealing profiles showing differing symptom levels and patterns. We aimed to explore typologies among clinical and non-clinical healthcare staff to elucidate heterogeneity of presentation.  Methods: This was a retrospective study using referral data from treatment-seeking healthcare staff in the North of England (N = 1600). We employed latent profile analysis using the PTSD International Trauma Questionnaire domains as profile indicators. We included covariates relating to role-type, depression, anxiety and mental health concerns before March of 2020.   Results: A model with six profiles fit the data best. Profile names were given as follows: 'No symptom'; 'Low symptom'; 'Low symptom (moderate Sense of current threat (Th_dx) and Functional impairment (FI))'; 'Moderate symptom (low Th_dx and high Avoidance (Av_dx))'; 'Moderate symptom'; and 'High symptom'. Covariates were shown to have differential predictive power on profile membership. Conclusions: The finding of profiles with pattern differences suggests a need for both differential and specifically targeted treatments, as well as a consideration of early intervention for those individuals with subclinical PTS symptoms. As expected, anxiety and depression were both predictors of several of the symptomatic profiles, with anxiety producing a larger effect. Further research is required to fully understand the link between role-type and PTS symptom typologies among HCW. .

Exploring heterogeneity in PTSD symptoms and associated predictors and outcomes in Afghanistan veterans: A latent profile analysis

Research on posttraumatic stress symptoms (PTSS) typically focuses on diagnosis or symptom severity, however, this overlooks the variety of symptom patterns that exist. Latent profile analysis was used to explore PTSS profiles in a sample of Norwegian Afghanistan veterans (n = 4052, 91.7% males). Multinomial logistic regression analyses were conducted to examine predictors and outcomes associated with PTSS profile membership. Three profiles emerged: Low Symptoms profile (85%); High Numbing and Arousal profile (13%); and High Symptoms profile (2%). Being female, lower number of deployments, barriers to disclose war-related experiences, and higher number of potentially morally injurious events (PMIEs) were associated with belonging to the High Symptoms profile compared to the High Numbing and Arousal (Male gender: OR = 0.37, p < .05; Number of deployments: OR = 0.68, p < .05; Barriers to disclose: OR = 1.39, p < .001; PMIEs: OR = 1.15. p < .05), or Low Symptoms profile (Male gender: OR = 0.36, p < .05; Number of deployments: OR = 0.67, p < .01; Barriers to disclose: OR = 1.80, p < .001; PMIEs: OR = 1.32. p < .001). Participants in the High Symptoms profile had the highest probability of mental health service use (0.37) and endorsing suicidal ideation (0.38), compared to the two other profiles (p < .01). Participants in the High Numbing and Arousal profile had a higher probability of seeking professional mental health care (0.17), endorsing suicidal ideation (0.16), and reporting more suicide attempts compared to the Low Symptom profile (0.02 vs. 0.00, p < .001). These findings highlight the importance of considering the heterogeneity of PTSS profiles and understanding the predictors and responses of individuals who exhibit elevated PTSS symptoms.

Classification of traumatic life events and substance use among persons admitted to inpatient psychiatry in Ontario, Canada

BACKGROUND

Trauma is commonly overlooked or undiagnosed in clinical care settings. Undetected trauma has been associated with elevated substance use highlighting the need to prioritize identifying individuals with undetected trauma through common characteristics.

OBJECTIVE

The purpose of this study is to identify classifications of traumatic life experiences and substance use among persons admitted to inpatient psychiatry in Ontario and to identify covariates associated with classification membership.

STUDY DESIGN

A population-based retrospective cohort study was conducted using interRAI Mental Health (MH) assessment data. Individuals were included who experienced traumatic life events (N = 10,125), in Ontario, Canada between January 1, 2015, to December 31, 2019.

RESULTS

Eight latent classes were identified that ranged from low (i.e., Class 1: Interpersonal Issues, Without Substance use) to high (i.e., Class 8: Widespread Trauma, Alcohol & Cannabis Addiction) complexity patterns of traumatic life events and substance use indicators. Classifications with similar trauma profiles were differentiated by patterns of substance use. For example, individuals in Class 2: Safety & Relationship Issues, Without Substance use and Class 3: Safety & Relationship Issues, Alcohol & Cannabis both had many estimates centered around the experience of victimization (e.g., victim of sexual assault, victim of physical assault, victim of emotional abuse). Multinomial logistic regression models highlighted additional factors associated with classifications such as homelessness, where those who were homeless were 2.09-4.02 times more likely to be in Class 6: Widespread Trauma & Substance Addiction.

INTERPRETATION

Trauma exposures are complex and varied among persons in inpatient psychiatry and can be further differentiated by substance use patterns. These findings provide a population-based estimate of the trauma experiences of persons in inpatient settings in Ontario, Canada. Findings demonstrate the importance of using comprehensive assessment to support clinical decision making in relation to trauma and substance.

Exploring transdiagnostic stress and trauma-related symptoms across the world: a latent class analysis

Background: Although trauma exposure is universally prevalent, the ways in which individuals respond to potentially traumatic events vary. Between-country differences have been identified as affecting the development and manifestation of transdiagnostic psychological symptoms, but it remains unclear how stress and trauma-related transdiagnostic symptoms and risk patterns differ based on geographic region.Objective: To explore whether there are distinct classes of stress and trauma-related transdiagnostic symptoms and to determine predictors of class membership in a global sample.Method: Participants (N = 8675) from 115 different countries were recruited online between 2020-2022 and completed the Global Psychotrauma Screen, which assesses stress and trauma exposure, related symptoms, and risk factors. A latent class analysis (LCA) was used to identify classes of stress and trauma-related symptoms per world region (African States, Asia-Pacific States, Eastern European States, Latin American and Caribbean States, Western European and Other States, and North America) and the total sample. Likelihood of class membership was assessed based on demographics, characteristics of the potentially traumatic event, and potential risk factors across the world regions.Results: Similar class compositions were observed across regions. A joint latent class analysis identified three classes that differed by symptom severity (i.e. high, moderate, low). Multinomial logistic regression analyses revealed several factors that conferred greater risk for experiencing higher levels of symptoms, including geographic region, gender, and lack of social support, among others.Conclusions: Stress and trauma-related symptoms seem to be similarly transdiagnostic across the world, supporting the value of a transdiagnostic assessment.

Sudden cardiac death and post-traumatic stress disorder: More research is needed

Sudden cardiac death is an event which is traumatic for the individuals, who survive and their relatives. Very few research is concentrated on these survivals and the symptoms arising from post-traumatic stress disorders. In this journal, Birk et al. report on twelve eligible cardiac arrest survivors contacted, of which ten were enrolled. The authors report on heart rate variability biofeedback, which is, according to the authors, a promising non-pharmacologic approach for reducing anxiety. The intervention was comprised of daily sessions of diaphragmatic paced breathing and real-time monitoring of cardiac activity guided by a smartphone app and heart rate monitor. Ninety percent of the patients had good scores for intervention acceptability and feasibility, and 80 % reported good scores for its appropriateness and usability for reducing fear. Trait anxiety decreased significantly pre-to-post intervention. We comment on this finding highlighting other studies targeting sudden cardiac death and supporting that more research with very large randomized clinical trials is needed.

Advances in the molecular neurobiology of posttraumatic stress disorder from global contexts: A systematic review of longitudinal studies

Trauma exposure is prevalent globally and is a defining event for the development of posttraumatic stress disorder (PTSD), characterised by intrusive thoughts, avoidance behaviours, hypervigilance and negative alterations in cognition and mood. Exposure to trauma elicits a range of physiological responses which can interact with environmental factors to confer relative risk or resilience for PTSD. This systematic review summarises the findings of longitudinal studies examining biological correlates predictive of PTSD symptomology. Databases (Pubmed, Scopus and Web of Science) were systematically searched using relevant keywords for studies published between 1 January 2021 and 31 December 2022. English language studies were included if they were original research manuscripts or meta-analyses of cohort investigations that assessed longitudinal relationships between one or more molecular-level measures and either PTSD status or symptoms. Eighteen of the 1,042 records identified were included. Studies primarily included military veterans/personnel, individuals admitted to hospitals after acute traumatic injury, and women exposed to interpersonal violence or rape. Genomic, inflammation and endocrine measures were the most commonly assessed molecular markers and highlighted processes related to inflammation, stress responding, and learning and memory. Quality assessments were done using the Systematic Appraisal of Quality in Observational Research, and the majority of studies were rated as being of high quality, with the remainder of moderate quality. Studies were predominantly conducted in upper-income countries. Those performed in low- and middle-income countries were not broadly representative in terms of demographic, trauma type and geographic profiles, with three out of the four studies conducted assessing only female participants, rape exposure and South Africa, respectively. They also did not generate multimodal data or use machine learning or multilevel modelling, potentially reflecting greater resource limitations in LMICs. Research examining molecular contributions to PTSD does not adequately reflect the global burden of the disorder.

Longitudinal PTSD network structure: measuring PTSD symptom networks over 5 years

BACKGROUND

Network modeling has been applied in a range of trauma-exposed samples, yet results are limited by an over reliance on cross-sectional data. The current analyses used posttraumatic stress disorder (PTSD) symptom data collected over a 5-year period to estimate a more robust between-subject network and an associated symptom change network.

METHODS

A PTSD symptom network is measured in a sample of military veterans across four time points (Ns = 1254, 1231, 1106, 925). The repeated measures permit isolating between-subject associations by limiting the effects of within-subject variability. The result is a highly reliable PTSD symptom network. A symptom slope network depicting covariation of symptom change over time is also estimated.

RESULTS

Negative trauma-related emotions had particularly strong associations with the network. Trauma-related amnesia, sleep disturbance, and self-destructive behavior had weaker overall associations with other PTSD symptoms.

CONCLUSIONS

PTSD's network structure appears stable over time. There is no single 'most important' node or node cluster. The relevance of self-destructive behavior, sleep disturbance, and trauma-related amnesia to the PTSD construct may deserve additional consideration.

Latent emotion profiles of PTSD and specific emotions predicting differential therapy outcomes in a dismantling study of cognitive processing therapy

Posttraumatic stress disorder (PTSD) is theoretically maintained by avoidance of emotions elicited from trauma-related beliefs. Whether PTSD symptom profiles and specific emotions predict treatment response is unknown. This secondary data analysis examined: a) whether individuals with PTSD can be sub-classified based on symptom clusters and specific emotions, and b) if these subgroups predict differential responses to cognitive versus exposure-based PTSD interventions. Women with physical or sexual assault-related PTSD were randomized to CPT (cognitive processing therapy elements only), CPT with written accounts (CPT+A), or written accounts (WA) only (n = 150). Participants completed baseline measures of PTSD, state anxiety, internalized anger, externalized anger, shame, and guilt, and weekly PTSD measures during and 6 months after treatment. Latent profile analyses revealed four subgroups: low symptoms and emotions; moderate-high reexperiencing, low internalized emotions (i.e., moderate-high reexperiencing, moderate avoidance/hyperarousal/guilt, low shame/internalized anger/anxiety); low reexperiencing, moderate emotions (i.e., low re-experiencing, moderate avoidance/hyperarousal/guilt, moderate other emotions); and high symptoms and emotions (high symptoms and emotions except moderate externalized anger). The high symptom and emotion subgroup experienced greater PTSD symptom improvements in cognitive conditions than WA. Other groups did not exhibit differential change across conditions. Cognitive interventions may be well-suited for severe PTSD with high self-directed emotions. CLINICALTRIALS.GOV IDENTIFIER: NCT00245232.

Patterns and predictors of perinatal posttraumatic stress symptoms: A latent transition analysis

BACKGROUND

Pregnancy is a time of increased risk for intimate partner violence (IPV), yet there is a dearth of prospective research examining the relationship between IPV and posttraumatic stress symptoms (PTSS) in the perinatal period. Further, relationships among different types of IPV and perinatal PTSS remain understudied.

METHODS

Latent class and transition analyses were used to examine classes of PTSS in pregnancy and postpartum, the longitudinal patterns of transitions across these classes, and the role of IPV types, childhood adversity, and depressive symptoms in PTSS presentation. Participants (N = 238) were drawn from two longitudinal studies of high-risk perinatal women.

RESULTS

Four latent PTSS classes emerged: High, Avoidant, Hypervigilant, and Low. Childhood adversity (χ²(3) = 13.09, p = .004), prenatal depression (χ²(3) = 17.58, p = .001), and psychological IPV (χ²(3) = 10.51, p = .01) were associated with membership in High, Avoidant, and Hypervigilant classes. Women with low prenatal PTSS continued to have low levels at postpartum. Women in higher severity classes during pregnancy tended to transition into classes with adjacent, and often lower, levels of symptom severity postpartum. Women in the High PTSS class in pregnancy with elevated levels of depression were significantly more likely to remain in the High PTSS class or transition into the Avoidant class at postpartum, compared to the Low PTSS class, χ²(3) = 11.84, p = .008.

LIMITATIONS

Relatively modest sample size precluded examination of a broader range of symptoms consistent with PTSD.

CONCLUSIONS

Findings highlight the importance of individualized approaches to assessing, monitoring, and treating perinatal PTSS.

The Impact of Just and Unjust War Events on Mental Health Need and Utilization within U.S. Service Members

Background: Soldiers are resilient to just war events, such as killing enemy combatants and life-threatening experiences, but these same soldiers appear to struggle with unjust war events, such as killing a noncombatant or being unable to help civilian women and children in need. This study is the first to examine how just and unjust war experiences are associated with clinical health service outcomes. Methods: Two samples of soldiers in different stages of readjustment from deployment were drawn from a longitudinal, survey-based study of a US Army brigade. Measures included items related to combat events, mental health utilization, perceived mental health need, PTSD, depression, and functional impairment. Results: After controlling for other kinds of combat events, just war events (i.e., life-threatening events and killing enemy combatants) predicted outcomes in soldiers who are less than three months post-deployment, but only predicted 2 of 26 outcomes in soldiers one year post deployment. In contrast, unjust war events were found to be robust predictors of short-term and long-term outcomes related to mental health need and utilization, even after controlling for exposure to other combat events. Conclusions: The results extend previous longitudinal research that suggests that exposure to unjust war events carry a heavier long-term mental health burden than other types of events. Additionally, Soldiers exposed to unjust war events had an unmet need for care one year post deployment that was not directly tied to PTSD or depression. The results question the emphasis on life-threat within mental health pathogenesis models.

Order effects in PTSD network analysis: important implications for diagnostic conceptualization, treatment refinement, and research

BACKGROUND

For decades confirmatory factor analysis (CFA) has been the preeminent method to study the underlying structure of posttraumatic stress disorder (PTSD); however, methodological limitations of CFA have led to the emergence of other analytic approaches. In particular, network analysis has become a gold standard to investigate the structure and relationships between PTSD symptoms. A key methodological limitation, however, which has significant clinical implications, is the lack of data on the potential impact of item order effects on the conclusions reached through network analyses.

METHODS

The current study, involving a large sample (N = 5055) of active duty army soldiers following deployment to Iraq, assessed the vulnerability of network analyses and prevalence rate to item order effects. This was done by comparing symptom networks of the DSM-IV PTSD checklist items to these same items distributed in random order. Half of the participants rated their symptoms on traditionally ordered items and half the participants rated the same items, but in random order and interspersed between items from other validated scales. Differences in prevalence rate and network composition were examined.

RESULTS

The prevalence rate differed between the ordered and random item samples. Network analyses using the ordered survey closely replicated the conclusions reached in the existing network analyses literature. However, in the random item survey, network composition differed considerably.

CONCLUSION

Order effects appear to have a significant impact on conclusions reached from PTSD network analysis. Prevalence rates were also impacted by order effects. These findings have important diagnostic and clinical treatment implications.

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.

Advancing Our Understanding of the Risk Factors Associated with Crossover Youth in the Child Welfare and Juvenile Justice Systems: A Trauma-Informed Research Agenda

Previous research has provided robust evidence demonstrating that a notable proportion of youth become involved in both the child welfare (CW) system and the juvenile justice (JJ) system, a population often referred to as crossover youth. Prior work has identified a number of risk factors associated with crossing over between these systems. However, there are limitations to the extant literature, key among which is a lack of systematic attention to the influence of trauma exposure and posttraumatic sequelae on the crossover trajectory. In contrast, viewing this research through a trauma-informed lens promises to enhance our ability to integrate findings across studies and to derive theoretically derived hypotheses about underlying mechanisms which will better inform future research and the development of effective prevention and intervention efforts. Accordingly, the purpose of this article is to present a trauma-informed research agenda that would strengthen future research in the field. After providing a brief critique of the existing studies that has documented known risk factors associated with the crossover population, we outline ways in which future research could apply relevant theoretical trauma-informed approaches, including developmental traumatology, to further advance our knowledge of risk factors and mechanisms associated with the crossover trajectory. We conclude by discussing policy and system-wide implications related to the proposed research agenda.

Deep learning model of fMRI connectivity predicts PTSD symptom trajectories in recent trauma survivors

Early intervention following exposure to a traumatic life event could change the clinical path from the development of post traumatic stress disorder (PTSD) to recovery, hence the interest in early detection and underlying biological mechanisms involved in the development of post traumatic sequelae. We introduce a novel end-to-end neural network that employs resting-state and task-based functional MRI (fMRI) datasets, obtained one month after trauma exposure, to predict PTSD symptoms at one-, six- and fourteen-months after the exposure. FMRI data, as well as PTSD status and symptoms, were collected from adults at risk for PTSD development, after admission to emergency room following a traumatic event. Our computational method utilized a per-region encoder to extract brain regions embedding, which were subsequently updated by applying the algorithmic technique of pairwise attention. The affinities obtained between each pair of regions were combined to create a pairwise co-activation map used to perform multi-label classification. The results demonstrate that the novel method's performance in predicting PTSD symptoms, in a prospective manner, outperforms previous analytical techniques reported in the fMRI literature, all trained on the same dataset. We further show a high predictive ability for predicting PTSD symptom clusters and PTSD persistence. To the best of our knowledge, this is the first deep learning method applied on fMRI data with respect to prospective clinical outcomes, to predict PTSD status, severity and symptom clusters. Future work could further delineate the mechanisms that underlie such a prediction, and potentially improve single patient characterization.

Identifying the subtypes of psychological profiles in senior undergraduate nursing students and its relationship with academic performance: A latent class analysis

BACKGROUND

Students' academic performance is closely related to their personal psychological factors. The subtypes and heterogeneity of psychological profiles among nursing students has not been systematically examined.

PURPOSE

To identify subtypes of psychological profiles among nursing students using latent class analysis (LCA).

METHODS

A cross-sectional study design included 379 senior nursing undergraduate students aged 18-22 from three medical colleges in Shanghai. The subjects were investigated by Ruminative Responses Scale, Academic Burnout Scale and Psychological Capital Scale and were categorized into subtypes by LCA.

RESULTS

Four latent classes were identified: Class 1 - General group; Class 2 - Negative psychological dominated group; Class 3 - Positive psychological dominated group; and Class 4 - Ambivalence psychological group. Students with higher exam failure rate were more likely to belong to Class 2. After adjusted for demographic variables, the subtypes of psychological profiles significantly correlated with academic performance.

CONCLUSIONS

The significant heterogeneities were noted between psychological profile subtypes and academic performance among senior undergraduate nursing students.

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

BACKGROUND

Definition of disorder subtypes may facilitate precision treatment for posttraumatic stress disorder (PTSD). We aimed to identify PTSD subtypes and evaluate their associations with genetic risk factors, types of stress exposures, comorbidity, and course of PTSD.

METHODS

Data came from a prospective study of three U.S. Army Brigade Combat Teams that deployed to Afghanistan in 2012. Soldiers with probable PTSD (PTSD Checklist for Diagnostic and Statistical Manual of Mental Disorders-Fifth Edition ≥31) at three months postdeployment comprised the sample (N = 423) for latent profile analysis using Gaussian mixture modeling and PTSD symptom ratings as indicators. PTSD profiles were compared on polygenic risk scores (derived from external genomewide association study summary statistics), experiences during deployment, comorbidity at three months postdeployment, and persistence of PTSD at nine months postdeployment.

RESULTS

Latent profile analysis revealed profiles characterized by prominent intrusions, avoidance, and hyperarousal (threat-reactivity profile; n = 129), anhedonia and negative affect (dysphoric profile; n = 195), and high levels of all PTSD symptoms (high-symptom profile; n = 99). The threat-reactivity profile had the most combat exposure and the least comorbidity. The dysphoric profile had the highest polygenic risk for major depression, and more personal life stress and co-occurring major depression than the threat-reactivity profile. The high-symptom profile had the highest rates of concurrent mental disorders and persistence of PTSD.

CONCLUSIONS

Genetic and trauma-related factors likely contribute to PTSD heterogeneity, which can be parsed into subtypes that differ in symptom expression, comorbidity, and course. Future studies should evaluate whether PTSD typology modifies treatment response and should clarify distinctions between the dysphoric profile and depressive disorders.

Latent classes of posttraumatic psychiatric comorbidity in the general population

Some narrow patterns of posttraumatic psychiatric comorbidity are well-established (e.g., posttraumatic stress disorder and substance use). However, broad multi-diagnosis profiles of posttraumatic comorbidity are poorly characterized. The goal of the current study was to use latent class analysis (LCA) to identify profiles of posttraumatic psychopathology from 11 International Classification of Diseases (ICD-10) diagnostic categories (e.g., stress, substance, depressive, psychosis, personality). Danish national registries were used to identify 166,539 individuals (median age = 41 years, range = <1 to >100) who experienced a traumatic event between 1994 and 2016 and were diagnosed with one or more mental disorders within 5 years. Two through 14-class LCA solutions were evaluated. A 13-class solution (a) provided the best fit, with the Bayes and Akaike Information Criteria reaching a minimum, (b) was broadly consistent with prior LCA studies, and (c) included several novel classes reflecting differential patterns of posttraumatic psychopathology. Three classes were characterized by high comorbidity: broad high comorbidity (M # diagnoses = 4.3), depression with stress/substance use/personality/neurotic disorders (M# diagnoses = 3.8), and substance use with personality/stress/psychotic disorders (M # diagnoses = 3.1). The other 10 classes were characterized by distinct patterns of mild comorbidity or negligible comorbidity. Compared to the mild and negligible comorbidity classes, individuals in high comorbidity classes were younger, had lower income, and had more pre-event psychiatric disorders. Results suggest that several different comorbidity patterns should be assessed when studying and treating posttraumatic psychopathology.

The Reward System and Post-Traumatic Stress Disorder: Does Trauma Affect the Way We Interact With Positive Stimuli?

Post-traumatic stress disorder (PTSD) is a highly prevalent disorder and a highly debilitating condition. Although anhedonia is an important construct of the disorder, the relationship between PTSD and reward functioning is still under-researched. To date, the majority of research on PTSD has focused on fear: fear learning, maintenance, and extinction. Here we review the relevant literature-including clinical observations, self-report data, neuroimaging research, and animal studies-in order to examine the potential effects of post-traumatic stress disorder on the reward system. Our current lack of sufficient insight into how trauma affects the reward system is one possible hindrance to clinical progress. The current review highlights the need for further investigation into the complex relationship between exposure to trauma and the reward system to further our understandings of the ethology of PTSD.