PTSD's factor structure and measurement invariance across subgroups with differing count of trauma types

Rethinking trauma-related psychopathology in the Hierarchical Taxonomy of Psychopathology (HiTOP)

Research on trauma exposure and its consequences has made tremendous progress in elucidating the role of traumatic life events in the development and maintenance of psychopathology as well as in evaluating interventions aimed at addressing the personal and public burden of trauma-related psychopathology. However, there is growing concern that problems with predominant definitions of posttraumatic syndrome (e.g., content coverage and scope, within-category heterogeneity, excessive diagnostic comorbidity) limit further efforts to fully conceptualize trauma-related psychopathology and deliver appropriate, personalized interventions. As demonstrated by an impressive body of research over the past several years, the Hierarchical Taxonomy of Psychopathology (HiTOP) presents a compelling alternative to traditional nosologies in terms of empirically based characterizations of psychopathology phenotypes, with evidence of strong utility for research and clinical applications. However, HiTOP's primary focus on descriptive psychopathology has resulted in an unacceptable gap regarding the conceptualization of trauma-related psychopathology from a dimensional, transdiagnostic perspective. We see an important opportunity to clarify what HiTOP can offer the field of traumatic stress research and articulate a future for trauma-related psychopathology within HiTOP. We argue for disaggregating psychopathology symptoms from their purported causes and, instead, developing a detailed taxonomy of traumatic events alongside an ever-evolving HiTOP model. Doing so will help identify empirically based phenotypes of trauma-related psychopathology that (a) go beyond the traditional PTSD criterion sets and (b) allow for the possibility that different features of traumatic experiences (e.g., type, duration, subjective meaning) may be associated with different symptom sequelae across different psychopathology spectra.

Mapping PTSD, depression, and anxiety: A network analysis of co-occurring symptoms in treatment-seeking first responders

First responders are at high risk for a range of co-occurring mental health conditions due to their repeated exposure to traumatic events. When first responders present for treatment, their complex presentation of symptoms including posttraumatic stress disorder (PTSD), depression, and generalized anxiety disorder (GAD) can prove challenging to differentiate for clinical purposes. Network analysis provides a means to identify the nuanced associations between the symptoms of these conditions and to identify groups of related symptoms. In this study, a treatment-seeking sample of first responders (N = 432) completed self-report measures of PTSD, depression, and GAD. Network analysis was used to identify symptom clusters within the sample. Our cross-sectional data yielded six empirically distinct communities: depression symptoms, GAD symptoms, and four communities comprising PTSD symptoms - intrusion and avoidance; irritability and aggression; negative affect; and arousal and sleep. Network associations underscore the heterogeneity of PTSD and also highlight overlapping and diverging symptoms of depression and GAD. These findings are discussed within the context of existing research on first responders, and recommendations for further study and treatment interventions are provided.

Differential symptom weighting in estimating empirical thresholds for underlying PTSD severity: Toward a "platinum" standard for diagnosis?

OBJECTIVE

Symptom counts as the basis for Post-Traumatic Stress Disorder (PTSD) diagnoses in the DSM presume each symptom is equally reflective of underlying disorder severity. However, the "equal weight" assumption fails to fit PTSD symptom data when tested. The present study developed an enhanced PTSD diagnosis based on (a) a conventional PTSD diagnosis from a clinical interview and (b) an empirical classification of full PTSD that reflected the relative clinical weights of each symptom.

METHOD

Baseline structured interview data from Project Harmony (N = 2658) was used. An enhanced diagnosis for full PTSD was estimated using an empirical threshold from moderated nonlinear factor analysis (MNLFA) latent PTSD scale scores, in combination with a full conventional PTSD diagnosis based on interview data.

RESULTS

One in 4 patients in the sample had a PTSD diagnosis that was inconsistent with their empirical PTSD grouping, such that the enhanced diagnostic standard reduced the diagnostic discrepancy rate by 20%. Veterans, and in particular female Veterans, were at greatest odds for discrepancy between their underlying PTSD severity and DSM diagnosis.

CONCLUSION

Psychometric methodologies that differentially weight symptoms can complement DSM criteria and may serve as a platform for symptom prioritization for diagnoses in future editions of DSM.

Linkages Between Childhood Maltreatment, Intimate Partner Violence, and Posttraumatic Stress Disorder Symptoms in Pregnant Hispanic Women: A Network Analysis

Pregnant Hispanic women are at increased risk for posttraumatic stress disorder (PTSD) in part due to greater risk of childhood maltreatment, intimate partner violence (IPV), and pregnancy-related vulnerabilities. However, PTSD, is a highly heterogenous diagnosis with numerous presentations. Individual PTSD symptoms may be differentially associated with specific types of maltreatment, IPV. Determining how IPV exposure across the lifespan is associated with specific symptoms of PTSD in pregnant Hispanic women is necessary to develop group-relevant models of this disorder and targeted interventions. The present study examined a network model of PTSD symptoms, childhood maltreatment, and adulthood IPV in a sample of pregnant Hispanic women (N = 198). Childhood emotional abuse and adulthood psychological distress had the highest bridge centrality. These types of exposures were most strongly associated with social isolation. Childhood emotional abuse was associated with more individual PTSD symptoms than any IPV type. These findings suggest that associations between PTSD symptoms and different types of IPV exposure vary. In addition, robust associations between childhood emotional abuse and PTSD symptoms suggest that this domain may be particularly important for the clinical assessment and intervention for pregnant women.

The Posttraumatic Stress Disorder (PTSD) Checklist for DSM-5: A Systematic Review of Existing Psychometric Evidence

The PTSD Checklist for DSM-5 (PCL-5) is a widely used self-rated measure of DSM-5 PTSD symptoms. The goal of this systematic review was to synthesize research on the psychometric properties of the PCL-5 to guide clinical and research applications. We focused on reliability, validity, factor structure, optimal cutoff scores, and sensitivity to clinical change indices. A systematic review of the literature following PRISMA guidelines was conducted using PubMed, PsycINFO, CINAHL, and PTSDpubs with search terms capturing selected psychometric indices of the PCL-5. The inclusion criteria were: peer-reviewed publication in English; primary focus on the PCL-5 psychometrics; empirical study; and study with adult samples. The search yielded 265 studies; 56 papers (amounting to 64 studies) met inclusion criteria and were reviewed. Findings generally indicated evidence for: acceptable internal consistency and test-retest reliability; construct validity; a 7-factor Hybrid Model; recommended cutoff scores between 31-33; and ability to index sensitivity to clinical change. To further advance knowledge and applications of the PCL-5, we need more research on abbreviated versions of the PCL-5, bifactor modeling as applied to the PCL-5, as well as on PCL-5 item difficulty estimates, discrimination parameters, and clinical change score estimates.

Measurement invariance of six language versions of the post-traumatic stress disorder checklist for DSM-5 in civilians after traumatic brain injury

Traumatic brain injury (TBI) is frequently associated with neuropsychiatric impairments such as symptoms of post-traumatic stress disorder (PTSD), which can be screened using self-report instruments such as the Post-Traumatic Stress Disorder Checklist for DSM-5 (PCL-5). The current study aims to inspect the factorial validity and cross-linguistic equivalence of the PCL-5 in individuals after TBI with differential severity. Data for six language groups (n ≥ 200; Dutch, English, Finnish, Italian, Norwegian, Spanish) were extracted from the CENTER-TBI study database. Factorial validity of PTSD was evaluated using confirmatory factor analyses (CFA), and compared between four concurrent structural models. A multi-group CFA approach was utilized to investigate the measurement invariance (MI) of the PCL-5 across languages. All structural models showed satisfactory goodness-of-fit with small between-model variation. The original DSM-5 model for PTSD provided solid evidence of MI across the language groups. The current study underlines the validity of the clinical DSM-5 conceptualization of PTSD and demonstrates the comparability of PCL-5 symptom scores between language versions in individuals after TBI. Future studies should apply MI methods to other sociodemographic (e.g., age, gender) and injury-related (e.g., TBI severity) characteristics to improve the monitoring and clinical care of individuals suffering from PTSD symptoms after TBI.

Estimating posttraumatic stress disorder severity in the presence of differential item functioning across populations, comorbidities, and interview measures: Introduction to Project Harmony

Multiple factor analytic and item response theory studies have shown that items/symptoms vary in their relative clinical weights in structured interview measures for posttraumatic stress disorder (PTSD). Despite these findings, the use of total scores, which treat symptoms as though they are equally weighted, predominates in practice, with the consequence of undermining the precision of clinical decision-making. We conducted an integrative data analysis (IDA) study to harmonize PTSD structured interview data (i.e., recoding of items to a common symptom metric) from 25 studies (total N = 2,568). We aimed to identify (a) measurement noninvariance/differential item functioning (MNI/DIF) across multiple populations, psychiatric comorbidities, and interview measures simultaneously and (b) differences in inferences regarding underlying PTSD severity between scale scores estimated using moderated nonlinear factor analysis (MNLFA) and a total score analog model (TSA). Several predictors of MNI/DIF impacted effect size differences in underlying severity across scale scoring methods. Notably, we observed MNI/DIF substantial enough to bias inferences on underlying PTSD severity for two groups: African Americans and incarcerated women. The findings highlight two issues raised elsewhere in the PTSD psychometrics literature: (a) bias in characterizing underlying PTSD severity and individual-level treatment outcomes when the psychometric model underlying total scores fails to fit the data and (b) higher latent severity scores, on average, when using DSM-5 (net of MNI/DIF) criteria, by which multiple factors (e.g., Criterion A discordance across DSM editions, changes to the number/type of symptom clusters, changes to the symptoms themselves) may have impacted severity scoring for some patients.

Confirmatory factor analysis of the Clinician-Administered PTSD Scale (CAPS-5) based on DSM-5 vs. ICD-11 criteria

INTRODUCTION

Many studies have investigated the latent structure of the DSM-5 criteria for posttraumatic stress disorder (PTSD). However, most research on this topic was based on self-report data. We aimed to investigate the latent structure of PTSD based on a clinical interview, the Clinician-Administered PTSD Scale (CAPS-5).

METHOD

A clinical sample of 345 participants took part in this multi-centre study. Participants were assessed with the CAPS-5 and the Posttraumatic Stress Disorder Checklist (PCL-5). We evaluated eight competing models of DSM-5 PTSD symptoms and three competing models of ICD-11 PTSD symptoms.

RESULTS

The internal consistency of the CAPS-5 was replicated. In CFAs, the Anhedonia model emerged as the best fitting model within all tested DSM-5 models. However, when compared with the Anhedonia model, the non-nested ICD-11 model as a less complex three-factor solution showed better model fit indices.

DISCUSSION

We discuss the findings in the context of earlier empirical findings as well as theoretical models of PTSD.

Psychometric properties of post-traumatic stress disorder (PTSD) checklist for DSM-5 in persons with serious mental illness

BACKGROUND

PCL-5 is a self-report measure consisting of 20 items that are used to assess the symptoms of Post-Traumatic Stress Disorder (PTSD) according to the DSM-5.

OBJECTIVE

This study evaluated the factor structure of the Post-Traumatic Stress Disorder (PTSD) Checklist for DSM-5 (PCL-5) in people with serious mental illness.

METHOD

The sample in Study 1 included 536 participants with serious mental illness who were receiving supported employment services through community mental health agencies or supported housing programmes. Confirmatory factor analysis assessed the fit of six different models of PTSD.

RESULTS

Results indicated that Armour's Hybrid 7-factor model composed of re-experiencing, avoidance, dysphoria, dysphoric arousal, anxious arousal, negative affect, anhedonia, and externalizing behaviours demonstrated the best fit. Study 2 found support for convergent validity for PCL-5 among 132 participants who met criteria for PTSD.

CONCLUSION

Findings provide support for the psychometric properties of the PCL-5 and the conceptualization of the 7-factor hybrid model and the 4-factor DSM-5 model of PTSD among persons living with serious mental illness.

Cross-Cultural Measurement Invariance in the Personality Inventory for DSM-5✰

The validity of cross-cultural comparisons of test scores requires that scores have the same meaning across cultures, which is usually tested by checking the invariance of the measurement model across groups. In the last decade, a large number of studies were conducted to verify the equivalence across cultures of the dimensional Alternative Model of Personality Disorders (DSM-5 Section III). These studies have provided information on configural invariance (i.e., the facets that compose the domains are the same) and metric invariance (i.e., facet-domain relationships are equal across groups), but not on the stricter scalar invariance (i.e., the baseline levels of the facets are the same), which is a prerequisite for meaningfully comparing group means. The present study aims to address this gap. The Personality Inventory for DSM-5 (PID-5) was administered to five samples differing on country and language (Belgium, Catalonia, France, Spain, and Switzerland), with a total of 4,380 participants. Configural and metric invariance were supported, denoting that the model structure was stable across samples. Partial scalar invariance was supported, being minimal the influence of non-invariant facets. This allowed cross-cultural mean comparisons. Results are discussed in light of the sample composition and a possible impact of culture on development of psychopathology.

Psychological trauma in different mechanisms of traumatic injury: A hospital-based cross-sectional study

BACKGROUND

Psychological distress following traumatic injury can influence the patient health, well-being and quality of life; however, this impact may partly vary according to the type and severity of injury. We aimed to study the predominant distress causing cluster and individual symptoms of Post-Traumatic Stress Disorders (PTSD) at the clinical and subthreshold level in patients with traumatic injuries, based on the mechanism of injury (MOI).

METHODS

A hospital based cross-sectional study was conducted at a Level 1 Trauma Center utilizing PTSD Checklist to diagnose PTSD after one month of the traumatic event. All patients suffering from psychological distresses were assessed by a clinical psychologist in the trauma section. PTSD diagnostic criteria from DSM-5 were used to classify the patients. The inclusion criteria comprised of adult trauma patients who were directly involved in traumatic injuries and admitted under the Trauma Surgery services for a minimum of one day; have ability to provide written informed consent and can be assessed with the PCL-5 checklist after 4 weeks post-injury.

RESULTS

Two hundred patients completed PCL-5 checklist, of them 26 (13.0%) were positive for PTSD and 174 (87%) had subthreshold scores. The mean age of participants was 34.4±11.8 years and males constituted 90.5%. Road traffic injury (RTI) was most the frequent injury mechanism (59%). PTSD positive patients with RTI, fall of heavy objects, pedestrian injury and assaults had highest average scores on clusters of negative alterations in mood and cognitions (16.9, 18.0, 18.5, 17.0 respectively), followed by hyperarousal. Symptom of always being on the guard and having repeated unwanted or disturbing memories of the incident, was reported by nearly 100% PTSD positive patients. Patients with subthreshold scores also reported distressing symptoms on all four clusters of PTSD.

CONCLUSIONS

Patients with different MOI showed a broad range of psychological problems with respect to symptom clusters. Negative alteration in mood and cognition followed by hyperarousal caused higher level of distress in patients post traumatic injuries. Subthreshold symptoms of PTSD are more common and deserve more attention.

Stressful Life Events and the Clinical Expression of Obsessive-Compulsive Disorder (OCD): An Exploratory Study

BACKGROUND

In obsessive-compulsive disorder (OCD), symptom content and severity appear to fluctuate over the course of the life cycle in accordance with stressful life events. The objective of this paper was to compare OCD patients with and without reported stressful life events (SLEs) in terms of the sociodemographics of patients and the clinical characteristics of OCD.

METHODS

This was a cross-sectional study involving 1001 patients with OCD. Data concerning SLEs were collected via the Yale OCD Natural History Questionnaire, while for OCD symptoms, the Dimensional Yale-Brown Obsessive-Compulsive Scale was used.

RESULTS

Of the 1001 OCD patients, 605 (60.5%) reported experiencing at least one SLE in their lifetime. Self-declared nonwhite skin color (odds ratio (OR) = 1.51), the presence of a sensory phenomenon (OR = 1.47), and comorbidity with post-traumatic stress disorder (PTSD) (OR = 2.38) were some of the logistic regression variables related to the reported SLEs with relevant statistical significance and risk (i.e., OR) values.

CONCLUSIONS

Our results indicate that SLEs may make Brazilian OCD patients vulnerable to the onset or exacerbation of obsessive-compulsive symptoms. The positive association of the occurrence of SLEs and sensory phenomena in this population could corroborate that environmental influences impact the neurobiology associated with OCD, and likely with other psychiatric disorders as well.

Measurement nonequivalence of the Clinician-Administered PTSD Scale by race/ethnicity: Implications for quantifying posttraumatic stress disorder severity

Research studies suggest racial/ethnic differences in posttraumatic stress disorder (PTSD) diagnosis and symptom severity. Few studies to date, however, have examined the extent to which these findings are due to differences in measurement properties of existing PTSD scales. This study examined measurement equivalence across race/ethnicity in the Clinician-Administered PTSD Scale (CAPS) by testing for differential item functioning (DIF) in the item response theory (IRT) framework. Participants were 506 trauma-exposed women (M = 39.41 years, SD = 8.94) who participated in the National Drug Abuse Treatment Clinical Trials Network Women and Trauma Study. PTSD severity score estimates were improved upon as part of IRT estimation incorporating symptom "weights" (i.e., factor loadings) and group-specific DIF. Six symptoms from the CAPS showed DIF, with the majority of differences in measurement driven by White/African American and White/Latina differences, particularly for (a) avoidance of thoughts and (b) a sense of foreshortened future. Despite both racial/ethnic minority groups being slightly (not significantly) more likely to receive a PTSD diagnosis, African Americans (p = .014; Cohen's d = -.22) and Latinas (p < .001; d = -.73) had significantly lower PTSD severity scores than Whites as estimated under IRT with group-specific DIF. Examination of PTSD severity scores based on symptom counts revealed these differences were either dampened (White/Latina difference d = -.39) or entirely negated (White/African American difference d = -.08). The findings suggest the importance of considering differences in symptom relevance across race/ethnicity and their impact on capturing symptom severity parallel to diagnostic criteria. Implications for clinical practice are discussed. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Examining the DSM-5 latent structures of posttraumatic stress disorder in a national sample of student veterans

To date, no studies have examined the latent structures of posttraumatic stress disorder (PTSD) within a sample of student veterans. To examine these constructs in a student veteran sample (n = 297), confirmatory factor analysis (CFA) was conducted on six different models of PTSD, including a one-factor model, based on the 20 symptoms found in the DSM-5; PTSD was assessed using the PCL-5. Global fit statistics suggest that fit across all models, including the 1-factor model, were good [RMSEAs(0.054-0.056); CFIs(0.928-0.940); SRMRs(0.043-0.045)], and the AIC was lowest for the seven-factor hybrid model. Statistical tests and fit guidelines for nested models suggest there is no quantitative advantage of a five, six, or seven-factor model over the existing DSM-5 four-factor model. Given the high percentage of student veterans that screened positive for a probable PTSD diagnosis (53 %) in this study compared to non-student veterans (11-20 %) and the general student population (11-15 %) found in other studies, further research is needed to assess the clinical utility of these symptoms and model structures.

Exploring the impact of trauma type and extent of exposure on posttraumatic alterations in 5-HT1A expression

The long-term behavioral, psychological, and neurobiological effects of exposure to potentially traumatic events vary within the human population. Studies conducted on trauma-exposed human subjects suggest that differences in trauma type and extent of exposure combine to affect development, maintenance, and treatment of a variety of psychiatric syndromes. The serotonin 1-A receptor (5-HT1A) is an inhibitory G protein-coupled serotonin receptor encoded by the HTR1A gene that plays a role in regulating serotonin release, physiological stress responding, and emotional behavior. Studies from the preclinical and human literature suggest that dysfunctional expression of 5-HT1A is associated with a multitude of psychiatric symptoms commonly seen in trauma-exposed individuals. Here, we synthesize the literature, including numerous preclinical studies, examining differences in alterations in 5-HT1A expression following trauma exposure. Collectively, these findings suggest that the impact of trauma exposure on 5-HT1A expression is dependent, in part, on trauma type and extent of exposure. Furthermore, preclinical and human studies suggest that this observation likely applies to additional molecular targets and may help explain variation in trauma-induced changes in behavior and treatment responsivity. In order to understand the neurobiological impact of trauma, including the impact on 5-HT1A expression, it is crucial to consider both trauma type and extent of exposure.

PTSD's risky behavior criterion: Associated risky and unhealthy behaviors and psychiatric correlates in a nationally representative sample

Criterion E2 ("reckless or self-destructive behavior") was added to the DSM-5 posttraumatic stress disorder (PTSD) criteria to reflect the established association between PTSD and risky and unhealthy behaviors (RUBs); however, previous research has questioned its clinical significance. To determine whether criterion E2 adequately captures reckless/self-destructive behavior, we examined the prevalence and associations of RUBs (e.g., substance misuse, risky sexual behaviors) with criterion E2 endorsement. Further, we examined associations between criterion E2 and psychiatric conditions (e.g., depressive disorders, anxiety disorders) in a population-based sample of trauma-exposed adults. We analyzed data from the 2012-2013 National Epidemiologic Survey on Alcohol and Related Conditions (N = 36,309). The Alcohol Use Disorder and Associated Disabilities Interview Schedule-5 assessed lifetime DSM-5 psychiatric conditions and self-reported RUBs. Among trauma-exposed adults (n = 23,936), multiple logistic regressions examined criterion E2's associations with RUBs and psychiatric conditions. After adjusting for covariates, all RUBs were associated with E2 endorsement (AOR range: 1.58-3.97; most prevalent RUB among those who endorsed E2: greater substance use than intended [57.0 %]) except binge eating, and E2 endorsement was associated with increased odds of PTSD, bipolar disorder, substance use disorders, and schizotypal, borderline, and antisocial personality disorders (AOR range: 1.65-2.75), and decreased odds of major depressive disorder (AOR = 0.76). Results support the clinical significance of criterion E2 through identifying associated RUBs and distinct correlates. These results may inform screening and intervention strategies for at-risk populations.

Relation between PTSD symptom clusters and positive memory characteristics: A network perspective

Positive memory characteristics relate to posttraumatic stress disorder (PTSD) severity. We utilized a network approach to examine relations between PTSD clusters (intrusions, avoidance, negative alterations in cognitions and mood [NACM], alterations in arousal and reactivity [AAR]) and positive memory characteristics (count, accessibility, valence, vividness, coherence, time perspective, sensory details). We identified differential relations between PTSD clusters and positive memory characteristics, and central/bridging symptoms. Participants were an Amazon Mechanical Turk-recruited sample of 206 individuals (M_age = 35.36; 61.20% females). We estimated a regularized Gaussian Graphic Model comprising four nodes representing the PTSD clusters and six nodes representing positive memory characteristics. Regarding cross-community relations, AAR (highest node strength) was negatively associated with positive memory count, valence, coherence, and accessibility; avoidance was positively and negatively associated with positive memory vividness and count respectively. The NACM-AAR and intrusion-avoidance edges were significantly stronger than most edges. From the PTSD community, AAR and avoidance had the highest bridge strength and bridge expected influence respectively; from the positive memory community, coherence and vividness had the highest bridge strength and bridge expected influence respectively. Results indicate the potential pivotal role of AAR, avoidance, coherence, and vividness in the PTSD-positive memory relation, which renders them assessment/treatment targets pending further investigation.

Alternative Models of DSM-5 Posttraumatic Stress Disorder in Portuguese Adolescents Exposed to Trauma and Childhood Adversity

The factor structure of DSM-5 posttraumatic stress disorder (PTSD) has been extensively debated, with evidence supporting the recently proposed seven-factor hybrid model. However, few studies examining PTSD symptom structure have assessed the implications of these proposed models on diagnostic criteria and PTSD prevalence. In the present study, we examined seven alternative DSM-5 PTSD models within a confirmatory factor analysis (CFA), using the Child PTSD Symptom Scale-Self-Report for DSM-5 (CPSS-5). Additionally, we generated prevalence rates for each of the seven models by using a symptom-based diagnostic algorithm and assessed whether substance abuse, depression, anxiety symptoms, and daily functioning were differentially associated with PTSD depending on the model used to derive the diagnosis. Participants were 317 adolescents aged 13-17 years (M = 15.93, SD = 1.23) who had experienced a DSM-5 Criterion A trauma and/or childhood adversity. The CFA results showed good fit indices for all models, with the seven-factor hybrid model presenting the best fit. The rates of PTSD diagnosis varied according to each model. The four-factor DSM-5 model presented the highest rate (30.6%), and the seven-factor hybrid model presented the lowest rate (17.4%). Similar to the CFA analysis, the inclusion criteria for the diagnosis based on the hybrid model also presented the strongest associations with daily functional impairment, odds ratio (OR) = 1.48, 95% CI [1.25, 1.75]; and adverse childhood experiences, OR = 1.46, 95% CI [1.16, 1.82]. Research and clinical implications of these results are discussed, and suggestions for future investigation are presented.

The symptoms at the center: Examining the comorbidity of posttraumatic stress disorder, generalized anxiety disorder, and depression with network analysis

Comorbid mental health disorders are highly common in trauma-exposed individuals with posttraumatic stress disorder (PTSD), depression, and generalized anxiety disorder (GAD) among the most common co-occurring conditions. Network models of psychopathology offer a novel method to understand how this comorbidity manifests. The present study examined the presence of symptom communities (groups of highly connected symptoms) within a network of these disorders and hub symptoms (symptoms that connect such communities). Cross-sectional data were obtained from a community sample (N = 1184) of trauma exposed adults. Network analyses identified 5 communities: 1 containing all depression and GAD symptoms and 4 for PTSD. The PTSD communities corresponded to symptoms of intrusion and avoidance, hyperarousal, dysphoria, and negative affect. These communities had varying levels of connectivity to the Depression & GAD community. Symptoms of GAD (inability to relax) and PTSD (restricted or diminished positive emotion) were identified as key hub symptoms for the network. The results suggest symptoms of depression and GAD are highly interrelated and that PTSD is heterogeneous. The comorbidity among these diagnoses is thought to stem from their overlap with negative affect.