Comparing posttraumatic stress disorder's symptom structure between deployed and nondeployed veterans

We tested two empirically validated 4-factor models of posttraumatic stress disorder (PTSD) symptoms using the PTSD Checklist: King, Leskin, King, and Weathers' (1998) model including reexperiencing, avoidance, emotional numbing, and hyperarousal factors, and Simms, Watson, and Doebbeling's (2002) model including reexperiencing, avoidance, dysphoria, and hyperarousal. Our aim was to determine which fit better in two groups of military veterans: peacekeepers previously deployed to a war zone (deployed group) and those trained for peacekeeping operations who were not deployed (nondeployed group). We compared the groups using multigroup confirmatory factor analysis. Adequate model fit was demonstrated among the nondeployed group, with no significant difference between King et al.'s (1998) model (separating avoidance and numbing) and Simms et al.'s (2002) similar model involving a dysphoria factor. A better fitting factor structure consistent with Simms et al.'s (2002) model was found in the deployed group. Comprehensive measurement invariance testing demonstrated significant differences between the deployed and nondeployed groups on all structural parameters, except observed variable intercepts (thus indicating similarities only in PTSD item severity). These findings add to researchers' understanding of PTSD's factor structure, given the revision of PTSD that will appear in the forthcoming 5th edition of the Diagnostic and Statistical Manual of Mental Disorders (American Psychiatric Association, 2010)--namely, that the factor structure may be quite different between groups with and without exposure to major traumatic events.     

Confirmatory factor analysis of the PTSD Checklist and the Clinician-Administered PTSD Scale in disaster workers exposed to the World Trade Center Ground Zero

Although posttraumatic stress disorder (PTSD) factor analytic research has yielded little support for the DSM-IV 3-factor model of reexperiencing, avoidance, and hyperarousal symptoms, no clear consensus regarding alternative models has emerged. One possible explanation is differential instrumentation across studies. In the present study, the authors used confirmatory factor analysis to compare a self-report measure, the PTSD Checklist (PCL), and a structured clinical interview, the Clinician-Administered PTSD Scale (CAPS), in 2,960 utility workers exposed to the World Trade Center Ground Zero site. Although two 4-factor models fit adequately for each measure, the latent structure of the PCL was slightly better represented by correlated reexperiencing, avoidance, dysphoria, and hyperarousal factors, whereas that of the CAPS was slightly better represented by correlated reexperiencing, avoidance, emotional numbing, and hyperarousal factors. After accounting for method variance, the model specifying dysphoria as a distinct factor achieved slightly better fit. Patterns of correlations with external variables provided additional support for the dysphoria model. Implications regarding the underlying structure of PTSD are discussed.     

Longitudinal factor structure of posttraumatic stress symptoms related to intimate partner violence

Confirmatory factor analysis (CFA) studies have suggested that a model of posttraumatic stress disorder (PTSD) that is characterized by 4 factors is preferable to competing models. However, the composition of these 4 factors has varied across studies, with 1 model splitting avoidance and numbing symptoms (e.g., D. W. King, G. A. Leskin, L. A. King, & F. W. Weathers, 1998) and the other including a dysphoria factor that combines numbing and nonspecific hyperarousal symptoms (L. J. Simms, D. Watson, & B. N. Doebbeling, 2002). Using the PTSD Checklist (F. W. Weathers, B. T. Litz, D. S. Herman, J. A. Huska, & T. M. Keane, 1993) and CFA, the authors compared these models with competing models. A model of PTSD with 4 intercorrelated factors of Intrusions, Avoidance, Dysphoria, and Hyperarousal was found superior among 396 medical patients who screened positive for intimate partner violence (IPV) and 405 women seeking services for IPV. Structural invariance testing indicated that this 4-factor model remains stable across service setting and time.     

Factor Structure of the PTSD Checklist in a Sample of OEF/OIF Veterans Presenting to Primary Care: Specific and Nonspecific Aspects of Dysphoria

Although DSM-IV-TR diagnostic criteria for posttraumatic stress disorder (PTSD) include three primary symptom clusters, recent evidence from confirmatory factor analyses suggest that the latent structure of PTSD is better represented by four factors, which will likely be reflected in the upcoming DSM-5. Given this likely transition from three to four clusters, the present study sought to examine specific and non-specific aspects of dysphoria in the factor structure of PTSD symptoms in a sample of OEF/OIF combat veterans presenting to a Veterans Affairs primary care clinic. PTSD symptoms were assessed using the PCL-M (Weathers et al. 1993). Results from confirmatory factor analyses suggested that a dysphoria factor involving a number of non-specific distress symptoms may be an important part of the PTSD symptom profile. After controlling for variance due to general psychological distress, we further found that factor loadings on the dysphoria factor were attenuated but continued to significantly load onto the factor, suggesting that dysphoria may be a specific part of the PTSD symptom constellation.     

The relationships between posttraumatic stress symptom clusters and marital intimacy among war veterans

This study examined (a) the relationships between posttraumatic stress disorder (PTSD) symptom clusters and marital intimacy among Israeli war veterans and (b) the role of self-disclosure and verbal violence in mediating the effects of PTSD avoidance and hyperarousal symptoms on marital intimacy. The sample consisted of 219 participants divided into 2 groups: ex-prisoners of war (ex-POWs; N = 125) and a comparison group of veterans who fought in the same war but were not held in captivity (N = 94). Ex-POWs displayed higher levels of PTSD symptoms and verbal violence and lower levels of self-disclosure than did controls. Although ex-POWs and controls did not differ in level of marital intimacy, they did, however, present a different pattern of relationships between PTSD clusters and intimacy. In ex-POWs, self-disclosure mediated the relations between PTSD avoidance and marital intimacy. Verbal aggression was also found via indirect effect of hyperarousal on marital intimacy. The results point to the importance of self-disclosure and verbal violence as interpersonal mechanisms for the relations between posttraumatic symptoms on marital intimacy of ex-POWs.     

Psychometric properties of the Impact of Event Scale - Revised

This study investigated the psychometric properties of the Impact of Event Scale—Revised (IES-R) in two samples of male Vietnam veterans: a treatment-seeking sample with a confirmed posttraumatic stress disorder (PTSD) diagnosis (N=120) and a community sample with varying levels of traumatic stress symptomatology (N=154). The scale showed high internal consistency (alpha=0.96). Confirmatory factor analysis did not provide support for a three-factor solution corresponding to the three subscales of intrusion, avoidance, and hyperarousal. Exploratory factor analysis suggested that either a single, or a two-factor solution (intrusion/hyperarousal and avoidance), provided the best account of the data. However, correlations among the subscales were higher in the community sample than in the treatment sample, suggesting that the IES-R may be sensitive to a more general construct of traumatic stress in those with lower symptom levels. The correlation between the IES-R and the PTSD Checklist was high (0.84) and a cutoff of 1.5 (equivalent to a total score of 33) was found to provide the best diagnostic accuracy.     

Posttraumatic stress disorder symptoms, physiological reactivity, alcohol problems, and aggression among military veterans

This study examined the association between posttraumatic stress disorder (PTSD) symptomatology and aggressive behavior among a sample of male Vietnam veterans (N = 1,328). Results indicated that the hyperarousal PTSD symptom cluster evidenced the strongest positive association with aggression at the bivariate level when compared with the other PTSD symptom clusters. When the PTSD symptom clusters were examined together as predictors, hyperarousal symptoms evidenced a significant positive relationship with aggression, and avoidance/numbing symptoms were negatively associated with aggression. Examination of potential mediators indicated that hyperarousal symptoms were directly associated with aggression and indirectly related to aggression via alcohol problems. Reexperiencing symptoms were associated with aggression only indirectly and through their positive association with physiological reactivity and negative association with alcohol problems. Study results highlight the complexity of the relationship between PTSD symptoms and aggression, and suggest possible mechanisms explaining this association.     

Relations Between PTSD and Distress Dimensions in an Indian Child/Adolescent Sample Following the 2008 Mumbai Terrorist Attacks

Posttraumatic stress disorder’s (PTSD) four-factor dysphoria model has substantial empirical support (reviewed in Elhai & Palmieri, Journal of Anxiety Disorders, 25, 849–854, 2011; Yufik & Simms, Journal of Abnormal Psychology, 119, 764–776, 2010). However, debatable is whether the model’s dysphoria factor adequately captures all of PTSD’s emotional distress (e.g., Marshall et al., Journal of Abnormal Psychology, 119(1), 126–135, 2010), which is relevant to understanding the assessment and psychopathology of PTSD. Thus, the present study assessed the factor-level relationship between PTSD and emotional distress in 818 children/adolescents attending school in the vicinity of the 2008 Mumbai terrorist attacks. The effective sample had a mean age of 12.85 years (SD?=?1.33), with the majority being male (n?=?435, 53.8 %). PTSD and emotional distress were measured by the UCLA PTSD Reaction Index (PTSD-RI) and Brief Symptom Inventory-18 (BSI-18) respectively. Confirmatory factor analyses (CFA) assessed the PTSD and BSI-18 model fit; Wald tests assessed hypothesized PTSD-distress latent-level relations; and invariance testing examined PTSD-distress parameter differences using age, gender and direct exposure as moderators. There were no moderating effects for the PTSD-distress structural parameters. BSI-18’s depression and somatization factors related more to PTSD’s dysphoria than PTSD’s avoidance factor. The results emphasize assessing for specificity and distress variance of PTSD factors on a continuum, rather than assuming dysphoria factor’s complete accountability for PTSD’s inherent distress. Additionally, PTSD’s dysphoria factor related more to BSI-18’s depression than BSI-18’s anxiety/somatization factors; this may explain PTSD’s comorbidity mechanism with depressive disorders.     

地震后青少年创伤后应激障碍的潜在结构分析

为考察地震后青少年创伤后应激障碍（PTSD）的潜在症状结构,本研究采用儿童创伤后应激障碍症状量表和儿童抑郁量表,对汶川地震一年后的746名中学生进行调查。利用验证性因素分析对竞争模型进行比较,结果发现包括侵入性、回避性、麻木性、精神痛苦性唤起和焦虑性唤起等5个症状的PTSD精神痛苦性唤起模型显著优于DSM-IV的PTSD模型、4维情感麻木模型和4维精神痛苦模型。效度分析的结果发现,PTSD精神痛苦性唤起模型具有良好的外部区分效度。所有结果均表明PTSD精神痛苦性唤起模型在汶川地震后青少年群体中具有良好的适用性,可以作为判定震后青少年PTSD症状的有效标准。     

Examination of the Relationship Between PTSD and Distress Tolerance in a Sample of Male Veterans With Comorbid Substance Use Disorders

Distress tolerance (DT), the perceived or actual ability to tolerate negative emotional or physical states, is inversely related to posttraumatic stress disorder (PTSD) symptoms in civilian, community samples. No studies to date have examined the relationship between DT and PTSD in clinical samples of veterans with a comorbid diagnosis of PTSD and a substance use disorder (SUD). Thus, the present study examined the relationship between DT and PTSD in a sample of predominately African American, male veterans (n = 75) diagnosed with comorbid PTSD and SUD (according to a structured clinical interview). Results of hierarchical linear regression models indicated that DT was inversely related to total PTSD symptom severity score, above and beyond depressive symptoms and SUD severity. Of the 4 symptom clusters, DT was inversely associated with intrusions and hyperarousal. These findings are discussed in light of previous work with civilian samples. Determining whether treatment incorporating DT skills would be useful for veterans undergoing PTSD treatment should be evaluated.     

Assessing PTSD in the military: Validation of a scale distributed to Danish soldiers after deployment since 1998

Since 1998, soldiers deployed to war zones with the Danish Defense (≈31,000) have been invited to fill out a questionnaire on post‐mission reactions. This provides a unique data source for studying the psychological toll of war. Here, we validate a measure of PTSD‐symptoms from the questionnaire. Soldiers from two cohorts deployed to Afghanistan with the International Security Assistance Force (ISAF) in 2009 (ISAF7, N = 334) and 2013 (ISAF15, N = 278) filled out a standard questionnaire (Psychological Reactions following International Missions, PRIM) concerning a range of post‐deployment reactions including symptoms of PTSD (PRIM‐PTSD). They also filled out a validated measure of PTSD‐symptoms in DSM‐IV, the PTSD‐checklist (PCL). We tested reliability of PRIM‐PTSD by estimating Cronbach's alpha, and tested validity by correlating items, clusters, and overall scale with corresponding items in the PCL. Furthermore, we conducted two confirmatory factor analytic models to test the factor structure of PRIM‐PTSD, and tested measurement invariance of the selected model. Finally, we established a screening and a clinical cutoff score by application of ROC analysis. We found high internal consistency of the PRIM‐PTSD (Cronbach's alpha = 0.88; both cohorts), strong item‐item (0.48–0.83), item‐cluster (0.43–0.72), cluster‐cluster (0.71–0.82) and full‐scale (0.86–0.88) correlations between PRIM‐PTSD and PCL. The factor analyses showed adequate fit of a one‐factor model, which was also found to display strong measurement invariance across cohorts. ROC curve analysis established cutoff scores for screening (sensitivity = 1, specificity = 0.93) and clinical use (sensitivity = 0.71, specificity = 0.98). In conclusion, we find that PRIM‐PTSD is a valid measure for assessing PTSD‐symptoms in Danish soldiers following deployment.     

Symptoms of Post-Traumatic Stress Disorder in Bereaved Children and Adolescents: Factor Structure and Correlates

This study investigated the factor structure and correlates of posttraumatic stress-disorder (PTSD) symptoms among children and adolescents confronted with the death of a loved one. Three hundred thirty-two bereaved children and adolescents (aged 8–18; 56.9 % girls) who all received some form of psychosocial support after their loss, completed self-report measures of PTSD, together with measures tapping demographic and loss-related variables, depression, prolonged grief, and functional impairment. Parent-rated indices of impairment were also collected. We first evaluated the fit of six alternative models of the factor structure of PTSD symptoms, using confirmatory factor analyses. Outcomes showed that the 4-factor numbing model from King et al. (Psychological Assessment 10, 90–96, 1998), with distinct factors of reexperiencing, avoidance, emotional numbing, and hyperarousal fit the data best. Of all participants, 51.5 % met DSM-IV criteria for PTSD. PTSD-status and scores on the PTSD factors varied as a function of age and gender, but were unrelated to other demographic and loss-related variables. PTSD-status and scores on the PTSD factors were significantly associated symptom-levels of depression, prolonged grief, and functional impairment. Findings complement prior evidence that the DSM-IV model of the factor structure of PTSD symptoms may not represent the best conceptualization of these symptoms and highlight the importance of addressing PTSD symptoms in children and adolescents seeking help after bereavement.     

Posttraumatic Stress Disorder Symptom Clusters and the Interpersonal Theory of Suicide in a Large Military Sample

Prior studies examining posttraumatic stress disorder (PTSD) symptom clusters and the components of the interpersonal theory of suicide (ITS) have yielded mixed results, likely stemming in part from the use of divergent samples and measurement techniques. This study aimed to expand on these findings by utilizing a large military sample, gold standard ITS measures, and multiple PTSD factor structures. Utilizing a sample of 935 military personnel, hierarchical multiple regression analyses were used to test the association between PTSD symptom clusters and the ITS variables. Additionally, we tested for indirect effects of PTSD symptom clusters on suicidal ideation through thwarted belongingness, conditional on levels of perceived burdensomeness. Results indicated that numbing symptoms are positively associated with both perceived burdensomeness and thwarted belongingness and hyperarousal symptoms (dysphoric arousal in the 5‐factor model) are positively associated with thwarted belongingness. Results also indicated that hyperarousal symptoms (anxious arousal in the 5‐factor model) were positively associated with fearlessness about death. The positive association between PTSD symptom clusters and suicidal ideation was inconsistent and modest, with mixed support for the ITS model. Overall, these results provide further clarity regarding the association between specific PTSD symptom clusters and suicide risk factors.     

高唤醒对创伤后应激障碍形成发展的影响及其神经机制

高唤醒是创伤后应激障碍(PTSD)的主要症状之一, 对创伤后应激障碍的形成与发展起核心作用。急性应激期产生的高唤醒可以预测其后PTSD的回避与麻木、再体验等症状的形成, 在创伤后早期, 降低唤醒程度可以减轻PTSD相关的症状表现。下丘脑-垂体-肾上腺轴异常变化会导致去甲肾上腺素(NE)、促肾上腺皮质激素释放因子(CRF)过度释放, 同时皮质醇(酮)水平下降, 这二者是高唤醒产生与维持的主要原因。另外, 5-羟色胺(5-HT)系统的高度激活也影响了高唤醒的形成。食欲素神经肽与NE、CRF与5-HT系统有密切的神经联系, 可能参与高唤醒的调节, 是近年来研究的一个热点。     

A meta-analytic investigation of the structure of posttraumatic stress disorder symptoms

Converging lines of evidence have called into question the validity of conceptualizations of posttraumatic stress disorder (PTSD) based on the Diagnostic and Statistical Manual of Mental Disorders (DSM; American Psychiatric Association, 2000) and suggested alternative structural models of PTSD symptomatology. We conducted a meta-analysis of 40 PTSD studies (N = 14,827 participants across studies) that used a DSM-based measure to assess PTSD severity. We aggregated correlation matrices across studies and then applied confirmatory factor analysis to the aggregated matrices to test the fit of competing models of PTSD symptomatology that have gained support in the literature. Results indicated that both prominent 4-factor models of PTSD symptomatology yielded good model fit across subsamples of studies; however, the model comprising Intrusions, Avoidance, Hyperarousal, and Dysphoria factors appeared to fit better across studies. Results also indicated that the best fitting models were not moderated by measure or sample type. Results are discussed in the context of structural models of PTSD and implications for the diagnostic nosology.     

Dimensionality of posttraumatic stress symptoms: a confirmatory factor analysis of DSM-IV symptom clusters and other symptom models

Recent exploratory [Taylor, S., Kuch, K., Koch, W. J., Crockett, D. J., & Passey, G. (1998). The structure of posttraumatic stress symptoms. Journal of Abnormal Psychology, 107, 154-160.] and confirmatory [Buckley, T. C., Blanchard, E. B., & Hickling, E. J. (1998). A confirmatory factor analysis of posttraumatic stress symptoms. Behaviour Research and Therapy, 36, 1091-1099; King, D. W., Leskin, G. A., King, L. A., & Weathers, F. W. (1998). Confirmatory factor analysis of the clinician-administered PTSD scale: evidence for the dimensionality of posttraumatic stress disorder. Psychological Assessment, 10, 90-96.] factor analytic investigations suggest that the three symptom clusters of posttraumatic stress disorder (PTSD) as defined in the Diagnostic and Statistical Manual [4th ed.; DSM-IV; American Psychiatric Association (1994). Diagnostic and statistical manual of mental disorders (4th ed.). Washington, DC: Author.] may not provide the best conceptualization of symptom dimensionality. However, the alternative models have not been in agreement, nor have they been compared against each other or models based on the DSM-IV. The purpose of the present investigation was to test a series of dimensional models suggested by these recent factor analytic investigations and the DSM-IV. Using data collected with the PTSD Checklist--Civilian Version [Weathers, F. W., Litz, B. T., Huska, J. A., & Keane, T. M. (1994). PCL-C for DSM-IV. Boston: National Center for PTSD--Behavioral Science Division.] from 349 referrals to a primary care medical clinic, we used confirmatory factor analysis to evaluate a: (1) hierarchical four-factor model, (2) four-factor intercorrelated model, (3) hierarchical three-factor model, (4) three-factor intercorrelated model, and (5) hierarchical two-factor model. The hierarchical four-factor model (comprising four first-order factors corresponding to reexperiencing, avoidance, numbing, and hyperarousal all subsumed by a higher-order general factor) provided the best overall fit to the data; although, all models met some standards specified for good model fit. More research is needed to establish the dimensional nature of PTSD symptoms and to assess whether identified dimensions differ as a function of the trauma experience. Implications for assessment, diagnosis, and treatment are also discussed.     

The Relationship Between Posttraumatic Stress Symptoms and Suicide Ideation Among Child Survivors Following the Wenchuan Earthquake

The association between posttraumatic stress disorder (PTSD) symptoms and suicide ideation was examined in a sample of 2,298 child survivors of the Wenchuan earthquake. Results indicated that intrusion, avoidance, hyperarousal symptom clusters, and PTSD total score were significantly associated with suicide ideation. Except for intrusion, other measures of PTSD remained as statistically significant correlates of suicide ideation even after controlling for age, gender, direct exposure, indirect exposure, and depression. Furthermore, results showed that PTSD symptoms had an indirect influence on suicide ideation that was mediated by depression. The findings suggest that avoidance and hyperarousal symptom clusters of PTSD may be two important indicators of suicide ideation among child survivors of the Wenchuan earthquake. Implications of the results for intervention and prevention of suicide behavior are discussed.     

Longitudinal Linkages Between Posttraumatic Stress Disorder Symptoms and Violent Behaviors Among Chinese Adolescents Following the Wenchuan Earthquake

This study was conducted to examine the longitudinal relations between posttraumatic stress disorder (PTSD) symptoms and violent behaviors. In this study, 415 adolescent survivors of the Wenchuan earthquake in China (May 12, 2008) were assessed by using self-report questionnaires 1 year (T1), 1.5 years (T2), and 2 years (T3) after the earthquake. The findings suggested that from 1 to 1.5 years after the earthquake, only intrusive symptoms of PTSD were a risk factor for violent behaviors, whereas violent behaviors were a risk factor for all 3 PTSD symptom clusters. Furthermore, 1.5 to 2 years after the earthquake, avoidance symptoms of PTSD were a risk factor for violent behaviors and hyperarousal symptoms of PTSD had no significant relation with violent behaviors.     

Associations between dimensions of anxiety sensitivity and PTSD symptom clusters in active-duty police officers

Prior studies have shown that anxiety sensitivity (AS) plays an important role in posttraumatic stress disorder (PTSD) symptom severity. The purpose of this study was to evaluate associations between empirically supported PTSD symptom clusters (i.e. reexperiencing, avoidance, numbing, hyperarousal) and AS dimensions (i.e. psychological concerns, social concerns, somatic concerns). Participants were 138 active-duty police officers (70.7% female; mean age = 38.9 years; mean time policing = 173.8 months) who, as a part of a larger study, completed measures of trauma exposure, PTSD symptoms, AS, and depressive symptoms. All participants reported experiencing at least one event that they perceived as traumatic, and 44 (31.9%) screened positive for PTSD. Officers with probable PTSD scored significantly higher on AS total as well as the somatic and psychological concerns dimensional scores than did those without PTSD. As well, a higher percentage of officers with probable PTSD scored positively on the AS-derived Brief Screen for Panic Disorder (Apfeldorf et al., 1994) compared with those without PTSD. A series of regression analyses revealed that depressive symptoms, number of reported traumas, and AS somatic concerns were significant predictors of PTSD total symptom severity as well as severity of reexperiencing. Avoidance was predicted by depressive symptoms and AS somatic concerns. Only depressive symptoms were significantly predictive of numbing and hyperarousal cluster scores. These findings contribute to understanding the nature of association between AS and PTSD symptom clusters. Implications for the treatment of individuals having PTSD with and without panic-related symptomatology are discussed.     

Relationships among Dispositional Attributional Style,Trauma-Specific Attributions,and PTSD Symptoms

The learned helplessness model and its various revisions suggest that causal attributions influence responses to events. This study examined relationships among the 3-factor symptom clusters of posttraumatic stress disorder (PTSD) represented in the 4th edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM–IV; American Psychiatric Association, 1994) and the individual dimensions of dispositional attributional style and trauma-specific attributions (i.e., internal–external, stable–unstable, global–specific). Relationships among attributions and clusters of PTSD symptoms represented by the 4-factor dysphoria model were also examined. Trauma-specific attributions were most predictive of PTSD symptoms, with higher associations for avoidance and numbing symptoms compared to arousal symptoms in the three-factor model and higher associations for dysphoria symptoms compared to arousal and avoidance symptoms in the four-factor dysphoria model. Results suggest that cognitive vulnerabilities could underlie the comorbidity between PTSD and depression and might represent a high-impact target for treatment.