Understanding Intensive Care Unit Family Caregivers' Vulnerability to Post-Traumatic Stress Disorder: The Impact of Neurotic Personality Traits, Emotional Suppression, and Perceptions of Unexpected Death

Rationale: Family members of patients who die in an intensive care unit (ICU) are at heightened risk of post-traumatic stress disorder (PTSD) symptoms. Not all surrogates develop these symptoms and heterogeneity exists in PTSD symptom clusters. Objectives: The study tested a personality model of PTSD symptoms in bereaved family caregivers of ICU patients. It was hypothesized that family members endorsing higher levels of neurotic personality traits would report higher levels of PTSD symptom clusters and that these associations would be explained by tendencies to view the patient's death as unexpected and to cope by suppressing their emotions. Methods: Participants were family members of ICU patients at an urban, academic medical center who either died or were discharged to an inpatient hospice unit. Participants were contacted for participation at least six months after the patient's death. Participants completed measures of personality, emotion regulation, and PTSD symptoms. Data were analyzed using path analysis. Results: Approximately one-third (35%) of the sample of 162 caregivers endorsed at-risk levels of PTSD. Individuals reporting higher levels of neurotic personality traits reported more PTSD symptoms (r = 0.53, p < 0.001). Perceptions that the patient death was unexpected partially explained the association of neuroticism with the intrusive re-experiencing PTSD symptoms (B = 0.45, p = 0.031). In contrast, emotional suppression partially explained the association of neuroticism with avoidance (B = 0.70, p = 0.010) and hyperarousal symptom clusters (B = 0.37, p = 0.041). Conclusions: Family vulnerability to PTSD after an ICU death can be conceptualized based on neurotic personality traits. Tendencies to view the patient's death as unexpected may contribute to intrusive thoughts and memories of the ICU experience. Individuals may avoid reminders and remain at heightened levels of arousal when they suppress their emotional experiences. Key Message: Family members who experience the death of a loved one following ICU treatment are vulnerable to PTSD symptoms. These reactions to ICU-related losses may be shaped by family members' personalities, expectations, and emotion regulation styles. Understanding these characteristics could inform family screening and intervention efforts in the ICU.

Human fear neurobiology reimagined: Can brain-derived biotypes predict fear-based disorders after trauma?

Human studies of fear neurobiology have established neural circuits that are activated to threatening stimuli, whether it be during Pavlovian fear conditioning or in response to naturally occurring threats. This circuitry involves the central and basolateral amygdala, as well as the bed nucleus of the stria terminalis, insula, hippocampus, and regulatory regions such as the anterior cingulate cortex and ventromedial prefrontal cortex. While research has found that fear-based disorders, such as anxiety and post-traumatic stress disorder, as associated with dysfunction in these circuits, there is substantial individual heterogeneity in the clinical presentation of symptoms. Recent work has used data-driven methods to derive brain biotypes that capitalize on the activity of the fear circuit and its interaction with other regions of the brain. These biotypes have great utility in both describing individual variation in psychopathology and in identifying individuals at greater risk for fear-based disorders after an environmental stressor, such as a traumatic event. The review discusses recent examples of how fear neurobiology studies can be leveraged to derive biotypes that may ultimately lead to improved treatment.

Patterns and predictive value of acute prolonged grief and posttraumatic stress in youngsters confronted with traumatic loss: A latent class analysis

Deaths of relatives and peers in potentially traumatizing circumstances may lead to symptoms of prolonged grief (PG, e.g.,yearning, preoccupation) and posttraumatic stress (PTS, e.g., re-experiencing, hypervigilance). There is limited knowledge about how symptoms of PG and PTS co-occur following such events. The current study aimed to identify patterns of DSM-5-TR defined PG symptomatology and PTS in a sample of 213 youngsters, involved in a school bus accident killing seven peers 2 months earlier. Using latent class analysis, three groups were identified evidencing moderate endorsement of most symptoms (Class 1), high endorsement of almost all but the avoidance symptoms (Class 2), and high endorsement of almost all symptoms (Class 3), respectively. Classes differed in terms of levels of grief, PTS, and depression, assessed concurrently, and-in a subgroup of n=137 participants-assessed at 16 month follow-up. E.g., Class 3 membership was associated with a greater likelihood of meeting criteria for DSM-5-TR defined prolonged grief disorder at follow-up. Gender (fewer females in Class 1) but not age and proximity to the accident were associated with class membership. Findings indicate that it is important to identify groups with elevated PG and PTS early after traumatic bereavement who may be en route to persistent mental health problems.

Sequential fear generalization and network connectivity in trauma exposed humans with and without psychopathology

While impaired fear generalization is known to underlie a wide range of psychopathology, the extent to which exposure to trauma by itself results in deficient fear generalization and its neural abnormalities is yet to be studied. Similarly, the neural function of intact fear generalization in people who endured trauma and did not develop significant psychopathology is yet to be characterized. Here, we utilize a generalization fMRI task, and a network connectivity approach to clarify putative behavioral and neural markers of trauma and resilience. The generalization task enables longitudinal assessments of threat discrimination learning. Trauma-exposed participants (TE; N = 62), compared to healthy controls (HC; N = 26), show lower activity reduction in salience network (SN) and right executive control network (RECN) across the two sequential generalization stages, and worse discrimination learning in SN measured by linear deviation scores (LDS). Comparison of resilient, trauma-exposed healthy control participants (TEHC; N = 31), trauma exposed individuals presenting with psychopathology (TEPG; N = 31), and HC, reveals a resilience signature of network connectivity differences in the RECN during generalization learning measured by LDS. These findings may indicate a trauma exposure phenotype that has the potential to advance the development of innovative treatments by targeting and engaging specific neural dysfunction among trauma-exposed individuals, across different psychopathologies.

Prevalence of the dissociative subtype of post-traumatic stress disorder: a systematic review and meta-analysis

The dissociative subtype of post-traumatic stress disorder (PTSD-DS) was introduced in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), and is characterised by symptoms of either depersonalisation or derealisation, in addition to a diagnosis of post-traumatic stress disorder (PTSD). This systematic review and meta-analysis sought to estimate the point prevalence of current PTSD-DS, and the extent to which method of assessment, demographic and trauma variables moderate this estimate, across different methods of prevalence estimation. Studies included were identified by searching MEDLINE (EBSCO), PsycInfo, CINAHL, Academic Search Complete and PTSDpubs, yielding 49 studies that met the inclusion criteria (N = 8214 participants). A random-effects meta-analysis estimated the prevalence of PTSD-DS as 38.1% (95% CI 31.5-45.0%) across all samples, 45.5% (95% CI 37.7-53.4%) across all diagnosis-based and clinical cut-off samples, 22.8% (95% CI 14.8-32.0%) across all latent class analysis (LCA) and latent profile analysis (LPA) samples and 48.1% (95% CI 35.0-61.3%) across samples which strictly used the DSM-5 PTSD criteria; all as a proportion of those already with a diagnosis of PTSD. All results were characterised by high levels of heterogeneity, limiting generalisability. Moderator analyses mostly failed to identify sources of heterogeneity. PTSD-DS was more prevalent in children compared to adults, and in diagnosis-based and clinical cut-off samples compared to LCA and LPA samples. Risk of bias was not significantly related to prevalence estimates. The implications of these results are discussed further.

Heterogeneity of posttraumatic stress symptoms in bereaved children and adolescents: Exploring subgroups and possible risk factors

Bereaved youths are at risk of developing posttraumatic stress (PTS), but there are large individual differences in presentation and severity of PTS symptoms among bereaved youths. The study sought to identify subgroups based on the distribution of self-rated loss-related PTS symptoms in a sample of 264 bereaved youths (aged 7-18). Based on latent class analysis, we identified three subgroups: no disturbance (37.9%), intermediate disturbance (39.0%) and pervasive disturbance (23.1%). Subgroups differed in PTS severity and symptom configuration. Specifically, avoidance was relatively more pronounced in bereaved youth with no and intermediate PTS disturbance, whereas emotional numbing was relatively more pronounced in bereaved youth with intermediate and pervasive PTS disturbance. Associations between subgroup membership, emotional stability and demographic and loss-related variables were also examined. Multinomial logistic regression indicated that youths in the pervasive disturbance subgroup reported lower emotional stability than youths in the no disturbance subgroup. Other variables were unrelated to subgroup membership. The study highlights the importance of considering the heterogeneity in PTS symptomatology in the diagnoses and treatment of loss-related traumatic stress in bereaved youth. Moreover, it underscores the need for further research on possible risk and protective factors involved in the maintenance and development of this traumatic stress.

Cyr K, Sareen J, Elhai JD, Zamorski MA. Comorbidity Patterns of Psychiatric Conditions in Canadian Armed Forces Personnel

OBJECTIVE

Posttraumatic stress disorder (PTSD) is often accompanied by other mental health conditions, including major depressive disorder (MDD), substance misuse disorders, and anxiety disorders. The objective of the current study is to delineate classes of comorbidity and investigate predictors of comorbidity classes amongst a sample of Canadian Armed Forces (CAF) Regular Force personnel.

METHODS

Latent class analyses (LCAs) were applied to cross-sectional data obtained between April and August 2013 from a nationally representative random sample of 6700 CAF Regular Force personnel who deployed to the mission in Afghanistan.

RESULTS

MDD was the most common diagnosis (8.0%), followed by PTSD (5.3%) and generalized anxiety disorder (4.7%). Of those with a mental health condition, LCA revealed 3 classes of comorbidity: a highly comorbid class (8.3%), a depressed-only class (4.6%), and an alcohol use-only class (3.1%). Multinomial logit regression showed that women (adjusted relative risk ratio [ARRR] = 2.77; 95% CI, 2.13 to 3.60; P < 0.01) and personnel reporting higher trauma exposure (ARRR = 4.18; 95% CI, 3.13 to 5.57; P < 0.01) were at increased risk of membership in the comorbid class compared to those without a mental health condition. When compared to those with no mental health condition, experiencing childhood abuse increased the risk of being in any comorbidity class.

CONCLUSIONS

Results provide further evidence to support screening for and treatment of comorbid mental health conditions. The role of sex, childhood abuse, and combat deployment in determining class membership may also prove valuable for clinicians treating military-related mental health conditions.

PTSD symptom profiles among Louisiana women affected by the 2010 Deepwater Horizon Oil Spill: A latent profile analysis

BACKGROUND

Few prior studies have investigated the latent class structure of PTSD using DSM-5 symptoms.

METHODS

To describe latent PTSD profiles among women who resided in Deepwater Horizon Oil Spill (DHOS)-affected coastal Louisiana communities, we used data from women enrolled in The Women and Their Children's Health (WaTCH) Study. Latent profile analysis was performed on the 20-item PTSD Checklist for DSM-5 (PCL-5) and model fit statistics for 2-class through 6-class solutions were compared. The pseudo-class draws method was employed on the best class solution to compare key covariates (including demographics, mental health indicators, DHOS exposure indicators, and trauma exposures) across classes.

RESULTS

Among 1997 women (mean age 46.63 ± 12.14 years, 56.8% white, mean trauma categories 6.09 ± 2.98, 9.55% previously diagnosed with PTSD), model fit statistics supported a five-class solution: low symptoms (mean PCL-5 = 4.10), moderate without mood alterations (mean = 19.73), moderate with mood alterations (mean = 34.24), severe without risk-taking (mean = 55.75), and severe with risk-taking (mean = 53.80). Women in the low-symptom class were significantly more likely to be white, have finished high school, have an income of at least $40,001 per year, be married or living with a partner, and endorse fewer trauma categories than women in the four symptomatic classes. Women with moderate to severe symptoms often had co-morbid depressive symptoms and no prior PTSD diagnosis.

LIMITATIONS

This study was limited by use of self-reported data and one-time assessment of PTSD symptoms.

DISCUSSION

Five distinct latent profiles of DSM-5 PTSD symptoms consisted of notably different individuals. Most affected women did not report prior PTSD diagnosis. Future research and practice identifying and addressing barriers to care for trauma-affected women in these communities is warranted.

A latent profile analysis of PTSD symptoms among UK treatment seeking veterans

Background: Significant numbers of individuals leave the military and experience symptoms of posttraumatic stress disorder (PTSD). Veterans with PTSD symptoms rarely experience them in isolation, more commonly they are co-morbid with a range of other difficulties. Objective: Latent profile analysis (LPA) was used to explore the heterogeneity of PTSD symptom presentation. Following this, regression analysis was used to examine variables that predicted membership to the identified PTSD profiles. Methods: Data on childhood adversity, socio-demographic characteristics and mental health outcomes was collected from 386 male veterans who had engaged with mental health services in the UK. Results: LPA identified a six-profile model to best describe the sample. There was a Low symptom profile, a Severe symptom profile and four Moderate symptom profiles. The Severe symptom profile was the largest one, accounting for 37.57% of the sample. Five out of the six profiles had mean PTSD scores above the cut-off for probable PTSD. Higher rates of common mental health difficulties were associated with more symptomatic profiles. Discussion: As the vast majority of veterans met criteria for probable PTSD, the finding of six different profiles differing primarily quantitatively, but to some extent also qualitatively, suggests the importance of moving away from a 'one-size fits all' approach when it comes to treatments, towards developing interventions that are tailored to meet the specific PTSD and co-morbid symptoms profiles.

Latent classes of PTSD symptoms in veterans undergoing residential PTSD treatment

Although most veterans in the Department of Veterans Affairs (VA) health system are treated for posttraumatic stress disorder (PTSD) in the outpatient setting, the VA has approximately 40 residential PTSD treatment facilities across the country for those requiring more intensive care. The symptom profiles of these veterans are poorly understood. Thus, the current study was designed to characterize classes of PTSD symptoms in a national sample of veterans undergoing residential treatment. We analyzed latent classes of PTSD symptoms among 2,452 veterans entering VA PTSD residential treatment in fiscal year 2013. The model with the best fit was a 4-class model comprising a low symptom class, moderate symptom class with high reexperiencing symptoms, a moderate symptom class with high emotional numbing, and a high symptom class. Compared to classes identified in outpatient samples, these classes were similar in type but greater in severity. Classes differed by age, race/ethnicity, trauma type, co-occurring medical conditions, co-occurring psychiatric conditions, and social functioning. Compared to the moderate class with high emotional numbing, those in the moderate class with high reexperiencing symptoms were more likely to be non-White, have greater pain severity, greater sleep problems, and were less likely to be depressed. Our findings suggest that veterans in residential treatment who have more severe PTSD symptoms also experience other medical and psychosocial stressors. A better understanding of symptom profiles may help to create more individualized treatment planning and thus potentially improve care for these veterans. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

Longitudinal patterns of PTSD symptom classes among US National Guard service members during reintegration

PURPOSE

The purpose of this study was to identify posttraumatic stress disorder (PTSD) symptom groups and assess their longitudinal progression during their first year of reintegration among United States (US) National Guard (NG) service members.

METHODS

A cohort of NG service members (n = 886) completed surveys at 6 and 12 months following their return from deployment to Iraq or Afghanistan. Latent class analysis (LCA) and latent transition analysis (LTA) were used to empirically derive groups based on their PTSD symptoms and examine their longitudinal course, respectively.

RESULTS

The best fitting model at both assessments was the four-class model, comprising an asymptomatic class (6 months = 54%; 12 months = 55%), a mild symptom class with elevated hyperarousal symptoms (6 months = 22%; 12 months = 17%), a moderate symptom class (6 months = 15%; 12 months = 15%), and a severe symptom class (6 months = 10%; 12 months = 13%). Based on LTA, stability of class membership at the two assessments was 0.797 for the asymptomatic class, 0.453 for the mild class, 0.560 for the moderate class, and 0.580 for the severe class. Estimated transition probabilities were greater with respect to transitioning to less severe, rather than more severe, classes over time.

CONCLUSIONS

The four latent PTSD classes were distinguished primarily by severity; however, the mild symptom class was characterized by higher levels of hyperarousal than other symptoms. Although the absolute number of individuals within classes remained fairly constant between 6 and 12 months, there was movement between severity classes. Most NG service members without symptoms continued to do well during the first year, with only an estimated 7% moving to the moderate or severe class.

Anhedonia and emotional numbing in treatment-seeking veterans: behavioural and electrophysiological responses to reward

Background: Anhedonia is a common symptom following exposure to traumatic stress and a feature of the PTSD diagnosis. In depression research, anhedonia has been linked to deficits in reward functioning, reflected in behavioural and neural responses. Such deficits following exposure to trauma, however, are not well understood. Objective: The current study aims to estimate the associations between anhedonia, PTSD symptom-clusters and behavioural and electrophysiological responses to reward. Methods: Participants (N = 61) were recruited among Danish treatment-seeking veterans at the Department of Military Psychology in the Danish Defence. Before entering treatment, participants were screened with symptom measurement instruments and participated in a joint behavioural-electrophysiological experiment. The experimental paradigm consisted of a signal-detection task aimed at assessing reward-driven learning. Simultaneous electrophysiological-recordings were analysed to evaluate neural responses upon receiving reward, as indicated by the Feedback-Related Negativity (FRN) component. Result: Anhedonia as conceptualized in depression correlated with behavioural learning (r = -0.28, p = .032). Neither anhedonia nor behavioural learning correlated with FRN. However, the anhedonia symptom cluster of PTSD did correlate with FRN (r = 0.29, p = .023). Extending upon this in an exploratory analysis, the specific PTSD-symptom emotional numbing was found to correlate moderately with FRN (r = 0.38, p = .003). Conclusion: The present data suggest that anhedonia in trauma-exposed individuals is related to the anticipatory aspect of reward, whereas the neural consummatory reward response seems unlinked. Interestingly, emotional numbing in the same population is related to the consummatory phase of reward, correlating with the FRN response. This suggests that anhedonia and emotional numbing in response to trauma might pertain to different phases of reward processing.

Psychiatric comorbidity pattern in treatment-seeking veterans

This study investigated comorbidity patterns in treatment-seeking veterans and currently-serving Canadian Forces members of an outpatient mental health clinic from September 2006-September 2014. Using a retrospective cohort design, latent class analysis was conducted to determine latent classes of comorbidity (including posttraumatic stress disorder [PTSD], major depressive disorder [MDD], generalized anxiety disorder, panic disorder, and alcohol use disorder [AUD]). Multiple logistic regression was used to determine which covariates (age, gender, number of deployments, and service duration) were predictors of latent class membership. Among the 486 participants, 79.2% had more than one probable mental health condition. The most common comorbidity was PTSD and MDD (61.5%), followed by PTSD and GAD (52.3%). Among those with PTSD, almost all (95%) had a subsequent condition, predominantly MDD (82.6% of those with PTSD had MDD). A two-class model was the best fitting model with a high comorbidity and a low comorbidity class. Older age and shorter service duration significantly increased the probability of being in the high comorbidity class when not controlling for member status. Results showed that treatment-seeking veterans and military personnel have high rates of comorbidity, particularly alongside PTSD. Therefore, it is critical for clinicians to be able to assess and treat comorbidity.

Consistency and factorial invariance of the Davidson trauma scale in heterogeneous populations: results from the 2010 Chilean earthquake

This investigation seeks to validate an application of a standardized post-traumatic stress symptom self-report survey, the Davidson Trauma Scale (DTS), with a large, heterogeneous population of earthquake victims. While previous studies have focused primarily on small samples, this investigation uses a unique dataset to assess the validity of this application of the DTS while accounting for heterogeneity and sample size. We use concurrent validity and reliability analysis tests to confirm the validity of the scale. Further, confirmatory factor analysis is used to test the fit of the data's factor structure against previously established trauma models. Finally, these fit tests are repeated across different mutually exclusive vulnerability subsets of the data in order to investigate how the invariance of the scale is affected by sample heterogeneity. We find that this particular application of the scale is, on the whole, reliable and valid, showing good concurrent validity. However, evidence of variability is found across specific vulnerability subsets, indicating that a heterogeneous sample can have a measurable impact on model fit. © 2016 The Authors International Journal of Methods in Psychiatric Research Published by John Wiley & Sons Ltd.

A network analysis of DSM-5 posttraumatic stress disorder symptoms and correlates in U.S. military veterans

OBJECTIVE

Recent developments in psychometrics enable the application of network models to analyze psychological disorders, such as PTSD. Instead of understanding symptoms as indicators of an underlying common cause, this approach suggests symptoms co-occur in syndromes due to causal interactions. The current study has two goals: (1) examine the network structure among the 20 DSM-5 PTSD symptoms, and (2) incorporate clinically relevant variables to the network to investigate whether PTSD symptoms exhibit differential relationships with suicidal ideation, depression, anxiety, physical functioning/quality of life (QoL), mental functioning/QoL, age, and sex.

METHOD

We utilized a nationally representative U.S. military veteran's sample; and analyzed the data from a subsample of 221 veterans who reported clinically significant DSM-5 PTSD symptoms. Networks were estimated using state-of-the-art regularized partial correlation models. Data and code are published along with the paper.

RESULTS

The 20-item DSM-5 PTSD network revealed that symptoms were positively connected within the network. Especially strong connections emerged between nightmares and flashbacks; blame of self or others and negative trauma-related emotions, detachment and restricted affect; and hypervigilance and exaggerated startle response. The most central symptoms were negative trauma-related emotions, flashbacks, detachment, and physiological cue reactivity. Incorporation of clinically relevant covariates into the network revealed paths between self-destructive behavior and suicidal ideation; concentration difficulties and anxiety, depression, and mental QoL; and depression and restricted affect.

CONCLUSION

These results demonstrate the utility of a network approach in modeling the structure of DSM-5 PTSD symptoms, and suggest differential associations between specific DSM-5 PTSD symptoms and clinical outcomes in trauma survivors. Implications of these results for informing the assessment and treatment of this disorder, are discussed.

Posttraumatic stress symptoms across the deployment cycle: A latent transition analysis

Our objective was to examine symptom-level changes in the course in posttraumatic stress disorder (PTSD) across the deployment cycle among combat-exposed Marines, and to determine the degree to which combat exposure and post-deployment stressor exposure predicted PTSD symptom profile transitions. We examined PTSD symptoms in a cohort of U.S. Marines (N = 892) recruited for the Marine Resiliency Study (MRS). Marines deployed as one battalion infantry unit to Afghanistan in 2010 and were assessed pre-deployment and one, five, and eight months post-deployment. We employed latent transition analysis (LTA) to examine Marines' movement across PTSD symptom profiles, determined by latent class analysis (LCA). LCAs revealed a 3-class solution one month pre-deployment, a 4-class solution at five months post-deployment, and a 3-class solution at eight months post-deployment. LTA revealed notable movement between classes over time, which depended chiefly on pre-deployment symptom presentation. Marines who reported few pre-deployment symptoms either maintained these low levels or returned to low levels by eight months. Marines who reported a moderate number of symptoms at pre-deployment had variable outcomes; 50% had reductions by eight months, and those who reported numbing symptoms at five months post-deployment tended to report more symptoms at eight months. Marines who reported more PTSD symptoms prior to deployment retained more symptoms eight months post-deployment. Combat exposure and post-deployment stressor exposure predicted profile transitions. Examining transitions between latent class membership over time revealed prognostic information about Marines' eight-month PTSD outcomes. The extent of pre-deployment PTSD symptoms was particularly informative of likely PTSD outcomes.

Homogeneity of Severe Posttraumatic Stress Disorder Symptom Profiles in Children and Adolescents Across Gender, Age, and Traumatic Experiences Related to 9/11

Patients with a posttraumatic stress disorder (PTSD) diagnosis according to the Diagnostic and Statistical Manual of Mental Disorders (4th ed., DSM-IV; American Psychiatric Association, 1994) will very likely not share all of the same symptoms, a consequence of the polythetic approach used in the DSM. We examined heterogeneity in the latent structure of PTSD symptoms using data from a previously published sample of 8,236 youth a subset of which had been exposed to the September 11, 2001 attacks (N = 6,670; Hoven et al., 2005). Latent class analysis was applied (a) to PTSD symptoms alone, (b) to symptoms in combination with impairment indicators, and (c) to PTSD symptoms when stratified by age and gender, as well as by empirically defined classes of exposure. We identified 4 symptom classes: no disturbance (49.4%), intermediate disturbance (2 classes; 21.5% and 18.6%, respectively), and severe disturbance (10.5%). These classes varied not only in the severity of symptoms, but also in the configuration of symptoms. We observed a high probability of endorsing both PTSD symptoms and indicators of impairment only in the severe disturbance class. A similar 4-class structure was found when the data were stratified by age, gender, and exposure classes. There were no significant differences as a function of age, gender, or exposure in the presence of severe PTSD. Heterogeneity was observed at intermediate levels of PTSD symptom severity. The specific PTSD symptoms that defined the severe PTSD profile could constitute the pathogenic aspects of a largely invariant and clinically meaningful PTSD syndrome.

PTSD REMISSION AFTER PROLONGED EXPOSURE TREATMENT IS ASSOCIATED WITH ANTERIOR CINGULATE CORTEX THINNING AND VOLUME REDUCTION

BACKGROUND

Brain structures underlying posttraumatic stress disorder (PTSD) have been a focus of imaging studies, but associations between treatment outcome and alterations in brain structures remain largely unexamined. We longitudinally examined the relation of structural changes in the rostral anterior cingulate cortex (rACC), a previously identified key region in the PTSD fear network, to outcome of prolonged exposure (PE) treatment.

METHOD

The sample included 78 adults (53 women): 41 patients with PTSD and 37 trauma-exposed healthy volunteers (TE-HCs). Patients underwent a 10-week course of PE treatment and completed pre- and posttreatment assessments and magnetic resonance imaging (MRI) structural scans. TE-HCs also underwent assessment and MRI at baseline and 10 weeks later. PE remitters (n = 11), nonremitters (n = 14), and TE-HCs, were compared at baseline on demographic and clinical characteristics and ACC structure. Remitters, nonremitters, and TE-HCs were compared for pre- to posttreatment clinical and structural ACC change, controlling for potential confounding variables.

RESULTS

There were no baseline differences in structure between PTSD and TE-HCs or remitters and nonremitters. Following treatment, PTSD remitters exhibited cortical thinning and volume decrease in the left rACC compared with PTSD nonremitters and TE-HCs.

CONCLUSIONS

These results, while in need of replication, suggest that PE treatment for PTSD, by extinguishing maladaptive trauma associations, may promote synaptic plasticity and structure change in rACC. Future research should explore possible underlying mechanisms.

The class-dimensional structure of PTSD before and after deployment to Iraq: Evidence from direct comparison of dimensional, categorical, and hybrid models

The assumption of specific etiology in posttraumatic stress disorder (PTSD) differentiates the disorder from most other psychiatric conditions. A 'risky test' of the assumption of specific etiology and resultant trauma-related symptom dimensions was conducted through structural modeling of PTSD symptoms in soldiers before (N=522) and after (n=423) a combat deployment to Iraq. If PTSD represents a discrete diagnostic entity that emerges after trauma exposure, we hypothesized either the number of latent classes should increase from pre- to post-deployment or symptom dimensions should qualitatively distinguish affected from unaffected classes following trauma exposure. Comparison of latent structural models revealed best fitting hybrid models for PTSD and depression with strong invariance of symptom dimensions across classes both before and after deployment and only quantitative (i.e., severity) differences between classes. These findings suggest PTSD is generally well-conceptualized as a dimensional syndrome worsened but not necessarily elicited by trauma exposure.

A systematic literature review of PTSD's latent structure in the Diagnostic and Statistical Manual of Mental Disorders: DSM-IV to DSM-5

The factor structure of posttraumatic stress disorder (PTSD) has been widely researched, but consensus regarding the exact number and nature of factors is yet to be reached. The aim of the current study was to systematically review the extant literature on PTSD's latent structure in the Diagnostic and Statistical Manual of Mental Disorders (DSM) in order to identify the best-fitting model. One hundred and twelve research papers published after 1994 using confirmatory factor analysis and DSM-based measures of PTSD were included in the review. In the DSM-IV literature, four-factor models received substantial support, but the five-factor Dysphoric arousal model demonstrated the best fit, regardless of gender, measurement instrument or trauma type. The recently proposed DSM-5 PTSD model was found to be a good representation of PTSD's latent structure, but studies analysing the six- and seven-factor models suggest that the DSM-5 PTSD factor structure may need further alterations.

Latent profile analyses of posttraumatic stress disorder, depression and generalized anxiety disorder symptoms in trauma-exposed soldiers

Posttraumatic stress disorder (PTSD) is comorbid with major depressive disorder (MDD; Kessler et al., 1995) and generalized anxiety disorder (GAD; Brown et al., 2001). We aimed to (1) assess discrete patterns of post-trauma PTSD-depression-GAD symptoms using latent profile analyses (LPAs), and (2) assess covariates (gender, income, education, age) in defining the best fitting class solution. The PTSD Checklist (assessing PTSD symptoms), GAD-7 scale (assessing GAD symptoms), and Patient Health Questionnaire-9 (assessing depression) were administered to 1266 trauma-exposed Ohio National Guard soldiers. Results indicated three discrete subgroups based on symptom patterns with mild (class 1), moderate (class 2) and severe (class 3) levels of symptomatology. Classes differed in symptom severity rather than symptom type. Income and education significantly predicted class 1 versus class 3 membership, and class 2 versus class 3. In conclusion, there is heterogeneity regarding severity of PTSD-depression-GAD symptomatology among trauma-exposed soldiers, with income and education predictive of class membership.

PTSD symptom presentation across the deployment cycle

BACKGROUND

Symptom-level variation in posttraumatic stress disorder (PTSD) has not yet been examined in the early post-deployment phase, but may be meaningful etiologically, prognostically, and clinically.

METHODS

Using latent class analysis (LCA), we examined PTSD symptom heterogeneity in a cohort of participants from the Marine Resiliency Study (MRS), a longitudinal study of combat Marines deployed to Iraq and Afghanistan (N=892). Typologies of PTSD symptom presentation were examined at one month pre-deployment and again one, five, and eight months post-deployment.

RESULTS

Heterogeneity in PTSD symptom presentation was evident at each assessment point, and the degree of symptom heterogeneity (i.e., the number of classes identified) differed by time point. Symptom patterns stabilized over time from notable symptom fluctuations during the early post-deployment period to high, medium, and low symptom severity by eight months post-deployment. Hypervigilance and exaggerated startle were frequently endorsed by participants in the initial month post-deployment. Flashbacks, amnesia, and foreshortened future were infrequently endorsed. Greater combat exposure, lifespan trauma, and avoidant coping generally predicted worse outcomes.

LIMITATIONS

Data were self-report and may have limited generalizability due to our lack of women and inclusion of only combat Marines. Attrition and re-ranging of data resulted in significant missing data and affected the representativeness of the sample.

CONCLUSIONS

Symptom-level variability is highest in the month following deployment and then stabilizes over time. Should post-deployment assessments occur too soon, they may capture common and transient early post-deployment reactions, particularly anxious arousal.

Portuguese version of the PTSD Checklist-Military Version (PCL-M)-I: Confirmatory Factor Analysis and reliability

The PTSD Checklist-Military Version (PCL-M) is a brief self-report instrument widely used to assess Post-traumatic Stress Disorder (PTSD) symptomatology in war Veterans, according to DSM-IV. This study sought out to explore the factor structure and reliability of the Portuguese version of the PCL-M. A sample of 660 Portuguese Colonial War Veterans completed the PCL-M. Several Confirmatory Factor Analyses were conducted to test different structures for PCL-M PTSD symptoms. Although the respecified first-order four-factor model based on King et al.'s model showed the best fit to the data, the respecified first and second-order models based on the DSM-IV symptom clusters also presented an acceptable fit. In addition, the PCL-M showed adequate reliability. The Portuguese version of the PCL-M is thus a valid and reliable measure to assess the severity of PTSD symptoms as described in DSM-IV. Its use with Portuguese Colonial War Veterans may ease screening of possible PTSD cases, promote more suitable treatment planning, and enable monitoring of therapeutic outcomes.

Typologies of posttraumatic stress disorder in treatment-seeking older adults

BACKGROUND

While it is well known that posttraumatic stress disorder (PTSD) is characterized by heterogeneous symptom clusters, little is known about predominant typologies of PTSD symptoms in older adults.

METHODS

Latent profile analyses (LPAs) were employed to evaluate predominant typologies of PTSD symptoms in a sample of 164 treatment-seeking older adults with childhood war-related trauma. Multinomial logistic regressions were conducted to evaluate predictors of class membership.

RESULTS

LPAs revealed that a 3-class solution best fit the data. These included an Intermediate Disturbance class (50.0%) and two Pervasive Disturbance classes, which differed with respect to severity of avoidance symptoms (Pervasive Disturbance-Low Avoidance: 33.5%, Pervasive Disturbance-High Avoidance: 16.5%). A greater number of traumatic events predicted membership in the Pervasive Disturbance classes. The Pervasive Disturbance-Low Avoidance class had a higher level of education than the Pervasive Disturbance-High Avoidance class. Compared to the Intermediate Disturbance class, the Pervasive Disturbance classes had the highest levels of depression, anxiety and somatization symptoms.

CONCLUSION

These results suggest that PTSD in treatment-seeking older adults may be characterized by three predominant typologies, which are differentiated by overall severity and avoidance symptoms, lifetime trauma burden, education level, and comorbid depression, anxiety, and somatization symptoms. These results underscore the importance of considering heterogeneity in the phenotypic presentation of PTSD in assessment and treatment approaches for this disorder in older adults.

Latent classes of PTSD symptoms in Iraq and Afghanistan female veterans

BACKGROUND

Recent studies have used latent class analysis (LCA) to identify subgroups of individuals who share similar patterns of PTSD symptom endorsement; however, further study is needed among female veterans, whose PTSD symptom expression may vary from that of their male counterparts. The current study examined latent PTSD symptom classes in female veterans who returned from recent military service in Iraq and Afghanistan, and explored military and demographic variables associated with distinct PTSD symptom presentations.

METHODS

A retrospective analysis was conducted using existing medical records from female Iraq and Afghanistan veterans who were new users of VA mental health outpatient (MHO) care, had received a PTSD diagnosis anytime during the post-deployment period, and completed the PTSD checklist within 30 days of their first MHO visit (N=2425).

RESULTS

The LCA results identified four latent classes of PTSD symptom profiles in the sample: High Symptom, Intermediate Symptom, Intermediate Symptom with High Emotional Numbing (EN), and Low Symptom. Race/ethnicity, age, time since last deployment, and distance from a VA facility emerged as predictors of PTSD symptom presentation.

LIMITATIONS

The current study was cross-sectional and utilized administrative data. The results may not be generalizable to female veterans from other service eras.

CONCLUSIONS

Longer times between end of last deployment and initiation of MHO services were associated with more symptomatic classes. Exploration of PTSD symptom presentation may enhance our understanding of the service needs of female veterans with PTSD, and suggests potential benefits to engaging veterans in MHO soon after last deployment.

Mindfulness-Based Stress Reduction for Posttraumatic Stress Symptoms

Mindfulness-based psychotherapies are associated with reductions in depression and anxiety. However, few studies address whether mindfulness-based approaches may benefit individuals with posttraumatic stress symptoms. The current pilot study explored whether group mindfulness-based stress reduction therapy reduced posttraumatic stress symptoms, depression, and negative trauma-related appraisals in 9 adult participants who reported trauma exposure and posttraumatic stress or depression. Participants completed 8 sessions of mindfulness-based stress reduction treatment, as well as pretreatment, midtreatment, and posttreatment assessments of psychological symptoms, acceptance of emotional experiences, and trauma appraisals. Posttraumatic stress symptoms, depression, and shame-based trauma appraisals were reduced over the 8-week period, whereas acceptance of emotional experiences increased. Participants’ self-reported amount of weekly mindfulness practice was related to increased acceptance of emotional experiences from pretreatment to posttreatment. Results support the utility of mindfulness-based therapies for posttraumatic stress symptoms and reinforce studies that highlight reducing shame and increasing acceptance as important elements of recovery from trauma.

Elucidating posttraumatic stress symptom profiles and their correlates among women experiencing bidirectional intimate partner violence

OBJECTIVE

This study employed latent class analysis to identify profiles of women experiencing intimate partner violence (IPV) based on the severity of posttraumatic stress disorder (PTSD) symptoms.

METHOD

Self-report data from a sample of 369 women experiencing bidirectional IPV was used.

RESULTS

A 3-class solution comprising low, moderate, and high PTSD severity profiles best fit the data. Profiles were differentially related to whether IPV victimization was considered traumatic (PTSD criterion A); whether functioning was impaired as a result of PTSD symptoms (PTSD criterion F); whether the woman met full diagnostic criteria for PTSD; depression symptom severity; and severity of psychological, physical, and sexual IPV victimization and use of IPV. An extremely high percentage of women in the high (96%) and moderate (88%) severity classes experienced functional impairment, although many did not meet full diagnostic criteria for PTSD.

CONCLUSIONS

Findings support the need for interventions individually tailored to one's treatment needs based on the nature of one's traumatic stressor and the impact of PTSD on daily functioning.

A person-centered analysis of posttraumatic stress disorder symptoms following a natural disaster: predictors of latent class membership

The present study applied latent class analysis to a sample of 810 participants residing in southern Mississippi at the time of Hurricane Katrina to determine if people would report distinct, meaningful PTSD symptom classes following a natural disaster. We found a four-class solution that distinguished persons on the basis of PTSD symptom severity/pervasiveness (Severe, Moderate, Mild, and Negligible Classes). Multinomial logistic regression models demonstrated that membership in the Severe and Moderate Classes was associated with potentially traumatic hurricane-specific experiences (e.g., being physically injured, seeing dead bodies), pre-hurricane traumatic events, co-occurring depression symptom severity and suicidal ideation, certain religious beliefs, and post-hurricane stressors (e.g., social support). Collectively, the findings suggest that more severe/pervasive typologies of natural disaster PTSD may be predicted by the frequency and severity of exposure to stressful/traumatic experiences (before, during, and after the disaster), co-occurring psychopathology, and specific internal beliefs.

Posttraumatic reactions to an earthquake: multidimensional scaling profile analysis of adolescent survivors

The current study examined the prototypical profiles of posttraumatic stress reactions among a sample of 282 adolescent survivors of the 2008 Wenchuan earthquake in China. Based on a dimensional perspective, the results of profile analysis via multidimensional scaling (PAMS) model revealed a two-dimensional solution corresponding to four profiles: intrusion, avoidance/arousal, partial avoidance, and hyperarousal. These profiles of posttraumatic stress symptoms equally manifested across gender. In addition, the Intrusion Profile was found to be associated with more elevated psychological distress symptoms. Results are discussed with respect to the typical posttraumatic stress symptoms following the earthquake.

Killing and latent classes of PTSD symptoms in Iraq and Afghanistan veterans

BACKGROUND

Our goal was to better understand distinct PTSD symptom presentations in Iraq and Afghanistan Veterans (N=227) and to determine whether those who killed in war were at risk for being in the most symptomatic class.

METHODS

We used latent class analysis of responses to the PTSD checklist and logistic regression of most symptomatic class.

RESULTS

We found that a four-class solution best fit the data, with the following profiles emerging: High Symptom (34% of participants), Intermediate Symptom (41%), Intermediate Symptom with Low Emotional Numbing (10%), and Low Symptom (15%). The largest group of individuals who reported killing (45%) was in the High Symptom class, and those who killed had twice the odds of being in the most symptomatic PTSD class, compared to those who did not kill. Those who endorsed killing a non-combatant (OR=4.56, 95% CI [1.77, 11.7], p<0.01) or killing in the context of anger or revenge (OR=4.63, 95% CI=[1.89, 11.4], p<0.001) were more likely to belong to the most symptomatic PTSD class, compared to those who did not kill.

LIMITATIONS

The study was retrospective and cross-sectional. The results may not generalize to veterans of other wars.

CONCLUSIONS

Killing in war may be an important indicator of risk for developing frequent and severe PTSD symptoms. This has implications for the mental healthcare of veterans, providing evidence that a comprehensive evaluation of returning veterans should include an assessment of killing experiences and reactions to killing.

A multi-sample confirmatory factor analysis of PTSD symptoms: what exactly is wrong with the DSM-IV structure?

Within the DSM-IV, PTSD symptoms are rationally classified as assessing one of three symptom domains: reexperiencing, avoidance/numbing, or hyperarousal. However, two alternative four-factor models have been advocated as superior to the DSM-IV framework, based on confirmatory factor analysis. In the Numbing model, symptoms of emotional numbing are differentiated from avoidance. In the Dysphoria model, several symptoms of numbing and hyperarousal are combined to form a factor purported to assess general psychological distress. Examination of these models, within 29 separate data sets, supports two conclusions. First, contrary to its conceptual underpinnings, the Dysphoria model differs empirically from the Numbing model solely in the correlation predicted between two hyperarousal symptoms; all other predicted correlations made by the two models are substantively identical. Second, when the factor analytic presumption of simple structure is relaxed to allow for potential presentation order effects, other plausible symptom structures emerge. In particular, the fit of the DSM-IV model improved dramatically and was a better fit to the data than either four-factor model. The ostensible inferiority of the DSM-IV model may be due to a methodological artifact stemming from the order in which symptoms are typically assessed. The provisional decision to revise the structure of PTSD symptoms in the DSM-5 in light of confirmatory factor analytic results may be misguided.

Heterogeneity of posttraumatic stress symptoms in a highly traumatized low income, urban, African American sample

Trauma is associated with a range of outcomes; identification of homogeneous profiles of posttrauma symptoms may inform theory, diagnostic refinement, and intervention. The present investigation applies a novel analytic technique to the identification of homogeneous subgroups of post-traumatic symptomatology in a large sample of African American adults reporting high levels of trauma. Latent profiles of posttraumatic stress disorder (PTSD) symptom severity were tested using latent profile analysis. Pseudo-class draws were used to characterize class differences across types of trauma, diagnostic comorbidities, and clinically-relevant features. Participants consisted of 2915 highly traumatized African Americans living in low income, urban setting and recruited from medical clinics in Atlanta, GA. Findings supported the presence of six distinct subgroups of posttraumatic stress symptom profiles described as resilient, moderate with amnesia, moderate with diminished interest, moderate without diminished interest and amnesia severe without amnesia, and severe overall. Observed subgroups differed across numerous historical and concurrent factors including childhood trauma, current and lifetime diagnoses of PTSD and major depression, lifetime substance use diagnosis, dissociation, depressive symptoms, emotional dysregulation, negative and positive affect, and history of hospitalization and suicidality. Posttraumatic stress disorder as currently defined is comprised of homogeneous subgroups with important differences in posttraumatic stress symptom endorsement as well as concomitant differentiation of associated diagnoses and clinically-relevant associated features.

Categorical vs dimensional classifications of psychotic disorders

OBJECTIVE

Both categorical and dimensional methods appear relevant to classifying psychotic disorders; however, there is no clear consensus on the most appropriate categories and dimensions or on the best approach for constructing nosologic criteria that integrate these 2 methods. This review examines the evidence on specific dimensions and categories that would best characterize psychoses.

METHOD

Entries in the MEDLINE database between 1980 and 2011 were searched for studies of the dimensional and/or categorical structure of psychosis. Studies were included if samples represented a spectrum of psychotic disorders and dimensions/categories were empirically derived using principal components analysis, factor analysis, or latent class analysis.

RESULTS

Most dimensional studies observed 4 or 5 dimensions within psychosis, with positive, negative, disorganization, and affective symptom domains most frequently reported. Substance abuse, anxiety, early onset/developmental, insight, cognition, hostility, and behavioral/social disturbance dimensions appeared in some studies. Categorical studies suggested 3 to 7 major classes within psychosis, including a class similar to Kraepelin's dementia praecox and one or more classes with significant mood components. Only 2 studies compared the relative fit of empirically derived dimensions and categories within the same data set, and each had significant limitations.

CONCLUSION

There is relatively consistent evidence on appropriate categories and dimensions for characterizing psychoses. However, the lack of studies directly comparing or combining these approaches provides insufficient evidence for definitive conclusions about their relative merits and integration. The authors provide specific recommendations for designing future studies to identify valid dimensions and/or categories of the psychoses and investigate hybrid approaches to model the structure of the underlying illnesses.

Statistical support for subtypes in posttraumatic stress disorder: the how and why of subtype analysis

A number of researchers have argued for the existence of different subtypes of posttraumatic stress disorder (PTSD). In the current paper we present criteria by which to assess these putative subtypes, clarify potential pitfalls of the statistical methods employed to determine them, and propose alternative methods for such determinations. Specifically, three PTSD subtypes are examined: (1) complex PTSD, (2) externalizing/internalizing PTSD, and (3) dissociative/nondissociative PTSD. In addition, three criteria are proposed for subtype evaluation, these are the need for (1) reliability and clarity of definition, (2) distinctions between subtypes either structurally or by mechanism, and (3) clinical meaningfulness. Common statistical evidence for subtyping, such as statistical mean difference and cluster analysis, are presented and evaluated. Finally, more robust statistical methods are suggested for future research on PTSD subtyping.

Latent classes of PTSD symptoms in Vietnam veterans

The authors examined heterogeneity in posttraumatic stress disorder (PTSD) symptom presentation among veterans (n = 335) participating in the clinical interview subsample of the National Vietnam Veterans Readjustment Study. Latent class analysis was used to identify clinically homogeneous subgroups of Vietnam War combat veterans. Consistent with previous research, three classes emerged from the analysis, namely, veterans with no disturbance (61.4% of the cohort), intermediate disturbance (25.6%), and pervasive disturbance (12.5%). The authors also examined physical injury, war-zone stressor exposure, peritraumatic dissociation, and general dissociation as predictors of class membership. The findings are discussed in the context of recent conceptual frameworks that posit a range of posttraumatic outcomes and highlight the sizable segment of military veterans who suffer from intermediate (subclinical) PTSD symptoms.

Assessing a five factor model of PTSD: is dysphoric arousal a unique PTSD construct showing differential relationships with anxiety and depression?

Posttraumatic stress disorder's (PTSD) latent structure has been widely debated. To date, two four-factor models (Numbing and Dysphoria) have received the majority of factor analytic support. Recently, Elhai et al. (2011) proposed and supported a revised (five-factor) Dysphoric Arousal model. Data were gathered from two separate samples; War veterans and Primary Care medical patients. The three models were compared and the resultant factors of the Dysphoric Arousal model were validated against external constructs of depression and anxiety. The Dysphoric Arousal model provided significantly better fit than the Numbing and Dysphoria models across both samples. When differentiating between factors, the current results support the idea that Dysphoric Arousal can be differentiated from Anxious Arousal but not from Emotional Numbing when correlated with depression. In conclusion, the Dysphoria model may be a more parsimonious representation of PTSD's latent structure in these trauma populations despite superior fit of the Dysphoric Arousal model.

Testing the dimensionality of posttraumatic stress responses in young Chinese adult earthquake survivors: further evidence for "dysphoric arousal" as a unique PTSD construct

BACKGROUND

This study investigated an alternative five-factor diagnostic model for posttraumatic stress disorder (PTSD) symptoms, and tested external convergent and discriminant validity of the model in a young Chinese sample of earthquake survivors.

METHODS

A total of 938 participants (456 women, 482 men) aged 15-20 years were recruited from a vocational school originally located in Beichuan County Town which was almost completely destroyed by the "Wenchuan Earthquake." The participants were administrated with the PTSD Checklist and the Hopkins Symptoms Checklist-25 12 months after the earthquake.

RESULTS

The results of confirmatory factor analysis showed that the five-factor intercorrelated model (intrusion, avoidance, numbing, dysphoric arousal, and anxious arousal) fit the data significantly better than the four-factor numbing model proposed by King et al. (1998: Psychol Assess 10:90-96) and the four-factor dysphoria model proposed by Simms et al. (2002: J Abnorm Psychol 111:637-647). Further analyses indicated that four out of five PTSD factors yielded significantly different correlations with external measures of anxiety versus depression.

CONCLUSIONS

The findings provide further empirical evidence in favor of the five-factor diagnostic model of PTSD, and carry implications for the upcoming DSM-5.

Posttraumatic stress disorder symptom structure in Chinese adolescents exposed to a deadly earthquake

This present study examined the structure of posttraumatic stress disorder (PTSD) symptoms in a large sample of Chinese adolescents exposed to a deadly earthquake. A total of 2,800 middle school students aged 12 to 18 years participated in the study 6 months after the "Wenchuan Earthquake". Results of confirmatory factor analysis indicated that a five-factor intercorrelated model composed of intrusion, avoidance, numbing, dysphoric arousal, and anxious arousal, fit data significantly better than both the four-factor numbing model King et al. (Psychological Assessment 10:90-96, 1998) and the four-factor dysphoria model Simms et al. (Journal of Abnormal Psychology 111:637-647, 2002). Further examination of the external convergent and discriminant validity revealed that except for the dysphoric arousal factor, the remaining four PTSD factors yielded significantly different correlations with external measures of anxiety vs. depression. The findings add to the limited literature on the factor structure of PTSD in youths and on the five-factor PTSD model. In addition, they provide more detail into the latent psychopathological processes of PTSD, and inform the forthcoming DSM-5.

Exploring the relationship between underlying dimensions of posttraumatic stress disorder and depression in a national, trauma-exposed military sample

BACKGROUND

Posttraumatic stress disorder (PTSD) and depression are highly comorbid and intercorrelated. Yet little research has examined the underlying processes explaining their interrelationship.

METHOD

In the present survey study, the investigators assessed the combined symptom structure of PTSD and depression symptoms, to examine shared, underlying psychopathological processes. Participants included 740 Canadian military veterans from a national, epidemiological survey, previously deployed on peacekeeping missions and administered the PTSD Checklist and Center for Epidemiological Studies-Depression Scale (CES-D).

RESULTS

An eight-factor PTSD/depression model fit adequately. In analyses validating the structure, PTSD's dysphoria factor was more related to depressive affect than to several other PTSD and depression factors. Somatic problems were more related to dysphoria than to other PTSD factors.

LIMITATIONS

Only military veterans were sampled, and without the use of structured diagnostic interviews.

CONCLUSIONS

Results highlight a set of interrelationships that PTSD's dysphoria factor shares with specific depression factors, shedding light on the underlying psychopathology of PTSD that emphasizes dysphoric mood.

Heterogeneity in clinical presentations of posttraumatic stress disorder among medical patients: testing factor structure variation using factor mixture modeling

The present study used factor mixture modeling to explore empirically defined subgroups of psychological trauma victims based on confirmatory factor analysis (CFA) and latent class analysis of posttraumatic stress disorder (PTSD) symptoms. We sampled 310 medical patients with a history of trauma exposure. Confirmatory factor analysis revealed that the 4-factor emotional numbing PTSD model yielded the best model fit. Using latent factor means derived from this model and the 4-factor dysphoria PTSD model (indexing severity on PTSD factors), 3 latent classes of participants were identified using factor mixture modeling. The 3-class model fit the data very well and was validated against external measures of anxiety and rumination.

Comparing alternative factor models of PTSD symptoms across earthquake victims and violent riot witnesses in China: evidence for a five-factor model proposed by Elhai et al. (2011)

The present study investigated the factor structure of posttraumatic stress disorder (PTSD) symptoms measured by the PTSD Checklist (PCL) in two large samples exposed to different traumatic events (an earthquake and a violent riot) from China. Despite the samples' difference in type of trauma, demographics, symptom severity, and elapsed time since trauma exposure, the results of a series of confirmatory factor analyses indicate that a five-factor intercorrelated model (intrusion, avoidance, numbing, dysphoric arousal, and anxious arousal) fit the data significantly better than the other alternative models including: the three-factor DSM-IV model, the four-factor numbing model (King et al., 1998), and the four-factor dysphoria model (Simms et al., 2002) in both samples. Implications and limitations regarding the results are discussed.

The factor structure of posttraumatic stress disorder: a literature update, critique of methodology, and agenda for future research

We present an update of recent literature (since 2007) exploring the factor structure of posttraumatic stress disorder (PTSD) symptom measures. Research supporting a four-factor emotional numbing model and a four-factor dysphoria model is presented, with these models fitting better than all other models examined. Variables accounting for factor structure differences are reviewed, including PTSD query instructions, type of PTSD measure, extent of trauma exposure, ethnicity, and timing of administration. Methodological and statistical limitations with recent studies are presented. Finally, a research agenda and recommendations are offered to push this research area forward, including suggestions to validate PTSD’s factors against external measures of psychopathology, test moderators of factor structure, and examine heterogeneity of symptom presentations based on factor structure examination.

Testing whether posttraumatic stress disorder and major depressive disorder are similar or unique constructs

Posttraumatic stress disorder (PTSD) and major depressive disorder (MDD) co-occur frequently, are highly correlated, and share three symptoms in common. In the present paper, the authors tested whether PTSD and MDD are similar or unique constructs by examining their symptoms using Rasch modeling. Data were used from the 766 trauma-exposed subjects in the National Comorbidity Survey-Replication (conducted in the early 2000s) with PTSD and MDD symptom ratings. Results demonstrate that MDD symptoms were less frequently endorsed than PTSD symptoms-even for the three symptoms shared between the disorders. PTSD and MDD items represented a single, underlying dimension, although modest support was found for a secondary sub-factor. Removing their shared symptoms, and additional depression-related dysphoria symptoms, continued to result in a single underlying PTSD-MDD symptom dimension. Results raise further questions about PTSD's distinctiveness from MDD, and the causes of their comorbidity.

Evidence for a unique PTSD construct represented by PTSD's D1-D3 symptoms

Two models of posttraumatic stress disorder (PTSD) have received the most empirical support in confirmatory factor analytic studies: King, Leskin, King, and Weathers' (1998) Emotional Numbing model of reexperiencing, avoidance, emotional numbing and hyperarousal; and Simms, Watson, and Doebbeling's (2002) Dysphoria model of reexperiencing, avoidance, dysphoria and hyperarousal. These models only differ in placement of three PTSD symptoms: sleep problems (D1), irritability (D2), and concentration problems (D3). In the present study, we recruited 252 women victims of domestic violence and tested whether there is empirical support to separate these three PTSD symptoms into a fifth factor, while retaining the Emotional Numbing and Dysphoria models' remaining four factors. Confirmatory factor analytic findings demonstrated that separating the three symptoms into a separate factor significantly enhanced model fit for the Emotional Numbing and Dysphoria models. These three symptoms may represent a unique latent construct. Implications are discussed.

Latent classes of adolescent posttraumatic stress disorder predict functioning and disorder after 1 year

OBJECTIVE

To identify latent classes of posttraumatic stress disorder (PTSD) symptoms in a national sample of adolescents, and to test their associations with PTSD and functional impairment 1 year later.

METHOD

A total of 1,119 trauma-exposed youth aged 12 through 17 years (mean = 14.99 years, 51% female and 49% male) participating in the National Survey of Adolescents-Replication were included in this study. Telephone interviews were conducted to assess PTSD symptoms and functional impairment at Waves 1 and 2.

RESULTS

Latent Class Analysis revealed three classes of adolescent PTSD at each time point: pervasive disturbance, intermediate disturbance, and no disturbance. Three numbing and two hyperarousal symptoms best distinguished the pervasive and intermediate disturbance classes at Wave 1. Three re-experiencing, one avoidance, and one hyperarousal symptom best distinguished these classes at Wave 2. The Wave 1 intermediate disturbance class was less likely to have a PTSD diagnosis, belong to the Wave 2 pervasive disturbance class, and report functional impairment 1 year later compared with the Wave 1 pervasive disturbance class. The Wave 1 no disturbance class was least likely to have PTSD, belong to the pervasive disturbance class, and report functional impairment at Wave 2.

CONCLUSIONS

This study suggests that PTSD severity-distinguishing symptoms change substantially in adolescence and are not characterized by the numbing cluster, contrary to studies in adult samples. These results may help to explain inconsistent factor analytic findings on the structure and diagnosis of PTSD, and emphasize that developmental context is critical to consider in both research and clinical work in PTSD assessment and diagnosis.