The Underlying Role of Negative Affect in the Association between PTSD,Major Depressive Disorder,and Generalized Anxiety Disorder

Clinicians and researchers have found differential diagnosis to be difficult, particularly for conceptually similar disorders. One category of particular interest has been distress or internalizing disorders, theorized to be related via an underlying construct of generalized distress or negative affect. The present study attempted to address the comorbidity of three distress disorders - posttraumatic stress disorder (PTSD), major depressive disorder (MDD), and generalized anxiety disorder (GAD) - using latent analyses by controlling for the variance attributable to negative affect. The sample consisted of 265 trauma-exposed individuals who completed self-report measures of PTSD, MDD, GAD, and negative affect. Confirmatory factor analysis was used to test initial model fit. Next, the model was re-computed, controlling for negative affect by regressing negative affectivity at the item-level. Results indicated that a significant amount of variance within and between these diagnostic categories is attributable to negative affect at both the item- and factor-level. The hypothesis that MDD’s non-somatic/affective factor and the GAD factor would have the highest attenuations in factor loadings after controlling for negative affect was supported. Therefore, negative affect significantly influences the co-occurrence of PTSD, MDD, and GAD clinically, emphasizing the need for transdiagnostic interventions for trauma victims.     

Heterogeneity in the Strength of the Relation Between Social Support and Post-Trauma Psychopathology

Potentially traumatic events (PTEs) increase risk for psychopathology, including posttraumatic stress disorder (PTSD), major depressive disorder (MDD), and generalized anxiety disorder (GAD). Social support (SS) is associated with reduced symptoms for each disorder. Each disorder, however, is highly heterogeneous such that they are comprised of clusters of different symptoms. It is unclear if SS is associated with all clusters equally. The current study examined the relation between SS and the symptom clusters of each disorder. Participants completed a battery of self-report assessments for PTSD, MDD, GAD, and SS. All participants experienced a Criterion A traumatic event. Although SS was significantly associated with all symptom clusters, the strength of relations varied. The relation between SS and MDD-affective was significantly stronger than its association with all other factors. The relations between SS and GAD, MDD-somatic, PTSD-AAR, and PTSD-NACM did not significantly differ. These relations were stronger than the relations between SS and the remaining PTSD factors. There was no significant difference in the relations between SS and PTSD-intrusions or PTSD-avoidance. These results suggest that SS is more closely aligned to specific aspects of post-trauma psychopathology.     

The influence of gender,age, Psychological resilience and family interaction factors upon anxiety and depression in non-autism spectrum disorder siblings of children with an autism spectrum disorder

The influence of gender, age, Psychological resilience and family interaction factors upon generalised anxiety disorder (GAD) and major depressive disorder (MDD) was investigated in 75 non-autism spectrum disorder (NASD) siblings who had a brother or sister with an autism spectrum disorder (ASD). GAD and MDD were much more prevalent than in comparable age group samples, and adolescent females had the highest MDD rates. Several Psychological resilience skills were significantly associated with lower GAD and MDD, particularly being able to recognise mistakes in their thinking (for children) and being able to remain in control of their anger (for adolescents). Suggestions are made for ways of encouraging NASD siblings to develop skills that may assist them in avoiding these disorders.     

Genetics of posttraumatic stress disorder

Posttraumatic stress disorder (PTSD) is a prevalent anxiety disorder marked by behavioral, physiologic, and hormonal alterations. PTSD is disabling and commonly follows a chronic course. The etiology of PTSD is unknown, although exposure to a traumatic event constitutes a necessary, but not sufficient, factor. A twin study of Vietnam veterans has shown significant genetic contribution to PTSD. The fact that PTSD's underlying genotypic vulnerability is only expressed following trauma exposure limits the usefulness of family-based linkage approaches. In contrast to the other major psychiatric disorders, large studies for the search of underlying genes have not been described in PTSD to date. Complementary approaches for locating involved genes include association-based studies employing case-control or parental genotypes for transmission dysequilibrium analysis and quantitative trait loci studies in animal models. Identification of susceptibility genes will increase our understanding of traumatic stress disorders and help to elucidate their molecular basis. The current review provides an up-to-date outline of progress in the field of PTSD.     

The Relationship Between a Hierarchical Transdiagnostic Model of Vulnerability Factors and Posttraumatic Stress Disorder Symptom Clusters

The latent structure of Post-Traumatic Stress Disorder (PTSD) symptomology is the subject of ongoing deliberation. The cognitive vulnerabilities of Negative Affect, Anxiety Sensitivity and Intolerance of Uncertainty have been shown to explain symptoms clusters in multiple anxiety and mood disorders, and may be able to offer further insight to explain PTSD symptomology. Using structural equation modelling, this study examines whether a hierarchical model consisting of the general cognitive factor of Negative Affect and the transdiagnostic risk factors of Anxiety Sensitivity and Intolerance of Uncertainty can explain variability among PTSD symptom clusters as defined by the DSM-5 and/or Dysphoria models of PTSD. Anxiety Sensitivity and Intolerance of Uncertainty were tested as mid-level factors between Negative Affect and the PTSD symptom constructs. The hierarchical model fit the data well in both the DSM-5 and Dysphoria models. Negative Affect consistently showed significant direct effects on each symptoms cluster in both models. Anxiety Sensitivity served as a significant mediator of Negative Affect for several symptom clusters in both models. Intolerance of Uncertainty was non-significant either as a direct effect or as a mediator of Negative Affect in all analyses. This study demonstrates how the hierarchical model of Negative Affect, Anxiety Sensitivity and Intolerance of Uncertainty may fit upon multiple PTSD symptom constructs and offers new directions for conceptualizing this disorder.

     

BDNF serum levels in subjects developing or not post-traumatic stress disorder after trauma exposure

Post-traumatic stress disorder (PTSD) is a syndrome resulting from exposure to a severe traumatic event that poses threatened death or injury and produces intense fear and helplessness. The neural structures implicated in PTSD development belong to the limbic system, an important region for emotional processing. Brain-derived neurotrophic factor (BDNF) is a neurotrophin that serves as survival factor for selected populations of central nervous system (CNS) neurons and plays a role in the limbic system by regulating synaptic plasticity, memory processes and behavior. Impaired BDNF production in the brain can lead to a variety of CNS dysfunctions including symptoms associated with PTSD. However, so far fewer studies have investigated this neurotrophin in patients with PTSD. Furthermore, given the multiple role of BDNF in various CNS disorders, it cannot be excluded that traumatic events per se may influence neurotrophin levels, without a direct association to the PTSD syndrome.     

Genetic and Environmental Contributions to Common Psychopathologies of Childhood and Adolescence: A Study of Twins and Their Siblings

We report findings based on analyses of self-reports of six common adolescent psychopathologies (attention deficit/hyperactivity disorder, ADHD; conduct disorder, CD; oppositional defiant disorder, ODD; generalized anxiety disorder, GAD; separation anxiety disorder, SAD; and major depressive disorder, MDD) in a sample of 1,162 male and female adolescent (12–19 years) twin pairs and 426 siblings. Prevalence statistics for past year and lifetime reports confirm differences between genders for CD, GAD, SAD, and MDD, and a lack of differences between twins and their non-twin siblings. Biometrical modeling was conducted to ascertain the relative influences of genes, and shared and non-shared environments contributing to these disorders. A more robust estimate of these parameters was obtained by including non-twin siblings. Age-specific thresholds were integrated into the analyses to appropriately model the developmental patterns of behavior. We found evidence for both genetic and non-shared environmental influences for all disorders. Shared environmental influences also seem to be important for MDD and lifetime GAD.     

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.     

A memory-based model of posttraumatic stress disorder: evaluating basic assumptions underlying the PTSD diagnosis

In the mnemonic model of posttraumatic stress disorder (PTSD), the current memory of a negative event, not the event itself, determines symptoms. The model is an alternative to the current event-based etiology of PTSD represented in the Diagnostic and Statistical Manual of Mental Disorders (4th ed., text rev.; American Psychiatric Association, 2000). The model accounts for important and reliable findings that are often inconsistent with the current diagnostic view and that have been neglected by theoretical accounts of the disorder, including the following observations. The diagnosis needs objective information about the trauma and peritraumatic emotions but uses retrospective memory reports that can have substantial biases. Negative events and emotions that do not satisfy the current diagnostic criteria for a trauma can be followed by symptoms that would otherwise qualify for PTSD. Predisposing factors that affect the current memory have large effects on symptoms. The inability-to-recall-an-important-aspect-of-the-trauma symptom does not correlate with other symptoms. Loss or enhancement of the trauma memory affects PTSD symptoms in predictable ways. Special mechanisms that apply only to traumatic memories are not needed, increasing parsimony and the knowledge that can be applied to understanding PTSD.     

Measurement differences from rating posttraumatic stress disorder symptoms in response to differentially distressing traumatic events

The authors explored differences in posttraumatic stress disorder (PTSD) symptoms as a result of rating symptoms from two separate, differentially distressing traumatic events. In an initial sample of 400 nonclinical participants, the authors inquired through a web survey about previous psychological trauma, instructing participants to nominate their most distressing and second most distressing traumatic events experienced. Using the PTSD Checklist, participants rated their PTSD symptoms separately from these worst and second worst events. Using the four-factor emotional numbing PTSD model in confirmatory factor analysis, results demonstrated evidence supporting separation of PTSD symptom rating sets from two differentially distressing traumas-specifically, the worst and second worst events. Measurement invariance tests revealed that factor loadings did not vary between the worst and second worst event PTSD ratings; item thresholds (indexing symptom severity) differed. Results generally support the recommended PTSD assessment protocol instructing participants to rate PTSD symptoms from a single, worst index event.     

Contribution of cognitive factors to the prediction of post-traumatic stress disorder, phobia and depression after motor vehicle accidents

Past research into the psychological consequences of traumatic events has largely focused on post-traumatic stress disorder (PTSD), although other anxiety disorders and depression are also common in the aftermath of trauma. Little is known about differential predictors of these conditions. The present study investigated the extent to which theoretically derived cognitive variables predict PTSD, phobias and depression after motor vehicle accidents. The cognitive predictors were compared to a set of established, mainly non-cognitive predictors. In addition, we tested how disorder-specific the cognitive predictors are. Participants (n=101) were interviewed within a year after having been injured in a motor vehicle accident. Diagnoses of PTSD, travel phobias and depression, symptom severities and predictor variables were assessed with self-report questionnaires and structured interviews. In multiple regression analyses, the sets of cognitive variables derived from disorder-specific models explained significantly greater proportions of the variance of the symptom severities than the established predictors (PTSD 76% vs. 45%, depression 72% vs. 46% and phobia 66% vs. 40%), and than cognitive variables derived from the models of the other disorders. In addition, the majority of individual cognitive variables showed the expected pattern of differences between diagnostic groups. The results support the hypothesis that disorder-specific sets of cognitive factors contribute to the development and maintenance of PTSD, phobias and depression following traumatic events.     

Perseverative thought: a robust predictor of response to emotional challenge in generalized anxiety disorder and major depressive disorder

Generalized anxiety disorder (GAD) and major depressive disorder (MDD) frequently co-occur, yet the reasons for their comorbidity remain poorly understood. In the present experiment, we tested whether a tendency to engage in negative, repetitive thinking constitutes a common risk process for the two disorders. A mixed sample of adults with comorbid GAD–MDD (n = 50), GAD only (n = 35), MDD only (n = 34), or no lifetime psychopathology (n = 35) was administered noncontingent failure and success feedback on consecutive performance tasks. Perseverative thought (PT), measured by negative thought intrusions during a baseline period of focused breathing, emerged as a powerful prospective predictor of responses to this experimental challenge. Participants reporting more frequent negative thought intrusions at baseline, irrespective of thought content or diagnostic status, exhibited a stronger negative response to failure that persisted even after subsequent success. Higher PT over the course of the experiment was associated with later behavioral avoidance, with negative affect and other traits closely linked to anxiety and depression, and with the presence and severity of GAD and MDD. These findings provide evidence for a broadly-defined PT trait that is shared by GAD and MDD and contributes to adverse outcomes in these disorders.     

Amnesia, traumatic brain injury, and posttraumatic stress disorder: a methodological inquiry

This study explored the relationship between mild traumatic brain injury (MTBI), amnesia, and posttraumatic stress disorder (PTSD). MTBI status and amnesia for the event were assessed in 307 consecutive admissions to a Level 1 Trauma Center. Amnesia did not always occur concurrently with MTBI: 18% of those with MTBI had full recall and over half had partial recall of the event. Just over 10% of participants developed PTSD by 12 months post-injury, with prevalence comparable across MTBI and non-MTBI groups. Non-significant differences in incidence of PTSD were apparent between those with full recall (9%), partial recall (14%) and no recall (7%). These data highlight the fact that PTSD may develop following trauma despite amnesia for the event, and illustrate the importance in both clinical and research settings of carefully examining the extent of amnesia.     

调控去甲肾上腺素能系统对防治创伤后应激障碍的影响

个体经历严重创伤性事件后可能会形成创伤后应激障碍(posttraumatic stress disorder, PTSD)。在创伤经历中形成的情绪记忆是以后发展为PTSD的重要病理机制。PTSD的形成涉及到情绪记忆的过度巩固, 而去甲肾上腺素能神经信号可增强情绪记忆的巩固和再巩固。因此, 在创伤记忆的巩固和再巩固期间阻断去甲肾上腺素能神经信号, 而在创伤记忆的消退期间增强去甲肾上腺素能神经信号, 可能会破坏和或抑制病理性的情绪记忆, 从而预防或治疗PTSD。     

Is the centralization of potentially traumatic events always negative? An expansion of the Centrality of Events Scale

The autobiographical memory model of posttraumatic stress disorder (PTSD) argues that centralizing a traumatic event into one's life story is a maladaptive process associated with increased PTSD symptoms. Current measures of event centralization make no reference to whether individuals centralize the event in a positive or negative way. This study examined 400 undergraduate participants using a modified version of the Centrality of Events Scale composed of 2 factors measuring both positive and negative event centralization. Exploratory factor analysis confirmed the 2‐factor structure. Negative event centralization was associated with PTSD symptoms to a greater degree than was positive event centralization, and negative event centralization mediated the relationship between neuroticism and PTSD symptoms. Combined, these results suggest that the effect of event centralization is dependent on the valence with which the individual centralizes the event. The relationship shown between negative event centralization and PTSD symptoms supports the autobiographical memory model of PTSD.     

PTSD,comorbid depression,and the cortisol waking response in victims of intimate partner violence: preliminary evidence

Posttraumatic Stress Disorder (PTSD) and Major Depressive Disorder (MDD) are two highly comorbid and debilitating disorders experienced by more than half of intimate partner violence victims (IPV). Hypothalamic–pituitary–adrenal (HPA) abnormalities are common in both disorders, though the direction of abnormalities often differs. The present study examined the relationship between comorbid PTSD and MDD, and the (salivary) cortisol waking response in 104 recently abused IPV victims. Waking cortisol levels, area under the waking curve with respect to ground (AUCg), and AUC with respect to increase (AUCi) were examined to determine the relation of HPA dynamics to comorbidity for basal versus more dynamic measures. Prior to accounting for comorbidity, women with PTSD or MDD showed significantly greater AUCi than women without the respective disorder. Accounting for comorbidity, PTSD only did not differ from other groups, while MDD only and PTSD + MDD showed greater AUCi than women with neither disorder. Results were nonsignificant for waking cortisol levels or AUCg. Results suggest that MDD drives elevated waking cortisol response, but not basal cortisol activity in recently abused IPV victims. Results demonstrate the importance of examining comorbid diagnoses and HPA activity from a dynamic perspective. Therapeutic implications are discussed.     

Examining the role of emotional avoidance in the relationship between posttraumatic stress disorder symptom severity and worry

A growing body of literature suggests that worry is a cognitive activity functioning to avoid unpleasant internal experiences such as negative thoughts, emotions, and somatic responses. Given the highly aversive internal events associated with posttraumatic stress disorder (PTSD), individuals experiencing PTSD symptoms following exposure to a traumatic event may be particularly motivated to engage in avoidant regulation strategies such as worry. Surprisingly, however, few studies to date have examined the relationship between PTSD and worry as well as potential factors that might explain this association. Therefore, the goal of this study was to examine the association between PTSD symptom severity and worry and the extent to which emotional avoidance explains this relationship. To this end, 207 college students with a history of traumatic exposure (meeting Criterion A for a PTSD diagnosis) completed a series of questionnaires assessing history of exposure to potentially traumatic events, PTSD symptom severity, emotional avoidance tendencies, and worry. Results demonstrated that PTSD symptom severity was positively associated with worry and emotional avoidance. Further, emotional avoidance was found to fully account for this relationship, providing support for the proposed emotionally avoidant function of worry. The implications of these findings for future research and the treatment of worry among individuals with a history of traumatic exposure are discussed.     

The impact of depression and PTSD symptom severity on trauma memory

Posttraumatic stress disorder (PTSD) and depression frequently co-occur following a traumatic event. Differences in the processing of autobiographical memory have been observed in both disorders in the form of overgeneralised memories and negative intrusive memories. The current study examined how symptoms of PTSD and depression influence the phenomenological characteristics of trauma memories. Undergraduate students who had experienced a traumatic event (n?=?696) completed questionnaires online including measures of PTSD and depressive symptom severity. They rated their trauma memory on several phenomenological characteristics using the Memory Experiences Questionnaire [Sutin, A. R., &; Robins, R. W. (2007). Phenomenology of autobiographical memories: The memory experiences questionnaire. Memory.]. Moderated multiple regression was used to examine how PTSD and depressive symptom severity related to each phenomenological characteristic. Symptoms of PTSD and depression were related separately and uniquely to the phenomenological characteristics of the trauma memory. PTSD severity predicted trauma memories that were more negative, contained higher sensory detail, and were more vivid. In contrast, depressive symptom severity predicted trauma memories that were less accessible and less coherent. These findings suggest that depressive and PTSD symptomatology affect traumatic memory differently and support a distinction between these two disorders.     

Path analytic examination of a cognitive model of PTSD

Ehlers and Clark (2000) developed a cognitive model of posttraumatic stress disorder (PTSD) symptom maintenance which implicated the role of posttraumatic cognitions and aspects of the trauma memory in maintaining symptoms via an increased sense of current threat. The aim of the current study was to empirically test a variant of this model using path analysis. Participants in the current study were 514 undergraduates at a midwestern university who reported experiencing at least one traumatic event. Path analyses examined various models of the possible relationships between one’s posttraumatic cognitions and the centrality of the traumatic event to the sense of self (considered an aspect of memory integration) in predicting current level of PTSD symptoms. Results indicate that both event centrality and posttraumatic cognitions are unique and independent predictors of current symptom level. Overall, the results of this study support aspects of Ehlers and Clark’s cognitive model of PTSD; cognitive appraisals of the self and centrality of the event were highly related to levels of distress. However, the current study suggests that overly integrated trauma memories may lead to greater distress and not poorly integrated ones as suggested by Ehlers and Clark.     

Specificity of autonomic arousal to DSM-IV panic disorder and posttraumatic stress disorder

Although research on the hierarchical model of anxiety and depression has confirmed that autonomic arousability (AA) is more germane to panic disorder with or without agoraphobia (PD/A) than other DSM-IV anxiety and mood disorders, studies have not evaluated the differential relevance of AA to posttraumatic stress disorder (PTSD). This issue was addressed in multivariate analytic models using 295 outpatients with anxiety and mood disorders. Consistent with prediction, the presence of current DSM-IV PTSD and PD/A was significantly predictive of AA, even when other forms of anxiety disorder comorbidity were held constant. Moreover, latent structural analyses indicated that PTSD and PD/A were the only DSM-IV anxiety disorder constructs to have significant direct effects on AA (in accord with previous findings, the DSM-IV constructs of generalized anxiety disorder, social phobia, and obsessive-compulsive disorder did not have significant structural relationships with AA). The current findings, which attest to the specificity of AA to PTSD and PD/A, are discussed in context of other clinically salient shared features of these disorders and their relevance to treatment and diagnostic classification.