Predictors of posttraumatic stress disorder and symptoms in adults: a meta-analysis

A review of 2,647 studies of posttraumatic stress disorder (PTSD) yielded 476 potential candidates for a meta-analysis of predictors of PTSD or of its symptoms. From these, 68 studies met criteria for inclusion in a meta-analysis of 7 predictors: (a) prior trauma, (b) prior psychological adjustment, (c) family history of psychopathology, (d) perceived life threat during the trauma, (e) posttrauma social support, (f) peritraumatic emotional responses, and (g) peritraumatic dissociation. All yielded significant effect sizes, with family history, prior trauma, and prior adjustment the smallest (weighted r = .17) and peritraumatic dissociation the largest (weighted r = .35). The results suggest that peritraumatic psychological processes, not prior characteristics, are the strongest predictors of PTSD.     

De novo conditioning in trauma-exposed individuals with and without posttraumatic stress disorder

Differential conditioning was assessed in 15 medication-free individuals meeting Diagnostic and Statistical Manual of Mental Disorders (4th ed.; American Psychiatric Association, 1994) criteria for chronic posttraumatic stress disorder (PTSD) and 18 trauma-exposed individuals who never developed PTSD (non-PTSD). Conditioned stimuli (CSs) were colored circles, and the unconditioned stimulus was a "highly annoying" electrical stimulus. Individuals with PTSD had higher resting heart rate (HR) and skin conductance (SC) levels and produced larger SC orienting responses. During conditioning, the PTSD group showed larger differential SC, HR, and electromyogram responses to the reinforced vs. nonreinforced stimuli (CS+ vs. CS-) compared with the non-PTSD group. Only PTSD participants continued to show differential SC responses to CS+ vs. CS- during extinction trials. Results suggest that individuals with PTSD have higher sympathetic nervous system arousal at the time of conditioning and are more conditionable than trauma-exposed individuals without PTSD.     

Psychotic symptoms in posttraumatic stress disorder

Recent data suggest that the presence of psychotic symptoms in patients suffering from posttraumatic stress disorder (PTSD) may represent an underrecognized and unique subtype of PTSD. Among combat veterans with PTSD, 30% to 40% report auditory or visual hallucinations and/or delusions. The presence of psychotic symptoms in PTSD is associated with a more severe level of psychopathology, similar to that of chronic schizophrenia. In this review, the differential diagnosis of psychotic symptoms in PTSD is discussed, including possible comorbid schizophrenia, psychotic depression, substance-induced psychosis, and personality disorder. A recent biologic study supporting the existence of a unique subtype of PTSD with psychotic features is also addressed, as are the similarities between PTSD with psychotic features and psychotic depression disorder. Finally, data on the treatment implications of psychotic symptoms in PTSD are presented. The intriguing recent findings on psychotic symptoms in PTSD need further investigation in noncombat-related PTSD populations before findings can be generalized to all individuals with PTSD.     

Incremental associations between facets of anxiety sensitivity and posttraumatic stress and panic symptoms among trauma-exposed adults

The present investigation examined incremental associations between anxiety sensitivity (AS) subfactors (e.g. physical, psychological, and social concerns) and posttraumatic stress and panic symptoms among trauma-exposed adults. These effects were examined above and beyond other theoretically relevant factors, including negative affectivity and number of types of trauma exposures. The 239 participants were selected from a university- and community-based sample (129 women; mean age = 23.0 years; SD = 9.6, range = 18-65), all of whom endorsed exposure to traumatic life events. The AS psychological concerns and AS physical concerns lower order factors evidenced distinct associations with posttraumatic stress symptoms and panic-relevant symptoms, respectively. Specifically, the AS psychological concerns facet was significantly incrementally predictive of posttraumatic stress-relevant avoidance symptoms. The AS physical concerns facet was significantly incrementally predictive of panic-relevant symptoms, including anxious arousal, body vigilance, and perceived control over anxiety-related events. Results are discussed in the context of the relevant theoretical literature pertaining to shared vulnerability and comorbidity between posttraumatic stress and panic.     

The role of anxiety sensitivity in the relationship between posttraumatic stress symptoms and negative outcomes in trauma-exposed adults

Background: The development of posttraumatic stress symptoms (PTSs) following a trauma is related to impairment, diminished quality of life, and physical health issues. Yet it is not clear why some trauma-exposed individuals experience negative outcomes while others do not. The purpose of this study was to determine the role of several influential factors related to PTS severity and negative outcomes. Methods: One hundred and twenty-two trauma-exposed adults were administered the following self-report measures: the Posttraumatic Stress Disorder Checklist-Civilian, the Trauma History Questionnaire-Short, the Anxiety Sensitivity Index-3, Depression and Anxiety Stress Scale 21, Sheehan Disability Scale, World Health Organization Quality of Life-BREF, and an abbreviated Patient Health Questionnaire. Primary Results: PTS severity was positively correlated with depressive symptom severity (r = 0.54, p < 0.001), chronicity of the most distressing trauma (r = 0.21, p = 0.017), and number of traumas (r = 0.22, p = 0.012). Main effects were found for PTS severity (β = ?0.38, p < 0.01) and anxiety sensitivity (AS; β = ?0.39, p < 0.01) on quality of life. No interaction was found between PTS severity and AS with any negative outcome. PTS severity mediated the relationship between AS and physical health issues (0.05; 95% CI: 0.02–0.08). Conclusion: This study helps clarify the role of various factors in the relationship between trauma and negative outcomes. Clinical and research implications are discussed.     

Connections among symptoms of obsessive-compulsive disorder and posttraumatic stress disorder: a case series

Theoretical, clinical, and empirical implications of the functional connections between symptoms of obsessive-compulsive disorder (OCD) and posttraumatic stress disorder (PTSD) are abundant. As such, four cases are presented here of men and women who met criteria for comorbid OCD and PTSD. All had been diagnosed with treatment-resistant OCD and were seeking treatment from an OCD specialty clinic or institute, all reported a history of traumatic experiences prior to the onset of OCD, and all appeared to demonstrate negative treatment outcomes. Upon examination, it appeared that symptoms of OCD and PTSD were connected such that decreases in OCD-specific symptoms related to increases in PTSD-specific symptoms, and increases in OCD-specific symptoms related to decreases in PTSD-specific symptoms. Speculations about the function of OCD symptoms in relation to post-traumatic psychopathology are put forth; and theoretical, research, and treatment implications are discussed.     

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.     

Memory in posttraumatic stress disorder: properties of voluntary and involuntary, traumatic and nontraumatic autobiographical memories in people with and without posttraumatic stress disorder symptoms

One hundred fifteen undergraduates rated 15 word-cued memories and their 3 most negatively stressful, 3 most positive, and 7 most important events and completed tests of personality and depression. Eighty-nine also recorded involuntary memories online for 1 week. In the first 3-way comparisons needed to test existing theories, comparisons were made of memories of stressful events versus control events and involuntary versus voluntary memories in people high versus low in posttraumatic stress disorder (PTSD) symptom severity. For all participants, stressful memories had more emotional intensity, more frequent voluntary and involuntary retrieval, but not more fragmentation. For all memories, participants with greater PTSD symptom severity showed the same differences. Involuntary memories had more emotional intensity and less centrality to the life story than voluntary memories. Meeting the diagnostic criteria for traumatic events had no effect, but the emotional responses to events did. In 533 undergraduates, correlations among measures were replicated and the Negative Intensity factor of the Affect Intensity Measure correlated with PTSD symptom severity. No special trauma mechanisms were needed to account for the results, which are summarized by the autobiographical memory theory of PTSD.     

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.     

Emotional processing in posttraumatic stress disorder

The emotional deficits associated with posttraumatic stress disorder (PTSD) are the least understood and the most understudied aspect of the syndrome. In this study, the connection was evaluated between trauma-context reactivity and subsequent emotional deficits in PTSD. Combat veterans with PTSD and well-adjusted veteran control participants were exposed to reminders of combat, after which their emotional behavior was assessed in response to a series of emotionally evocative images. Under the neutral condition, both groups exhibited emotional behavior modulated by stimulus valence. Partially consistent with the conceptual model described by B. Litz (1992), the PTSD group exhibited suppressed expressive-motor responses to positively valenced images, in comparison with the control group, only after being exposed to a trauma-related prime. Contrary to expectations, the PTSD group showed no augmentation of emotional response to negatively valenced cues after being exposed to trauma reminders. However, the PTSD group responded to all images, in both prime conditions, with higher heart rate reactivity, suggesting an automatic preparation for demand or threat in any uncertain emotional context. Possible causes and consequences of these results are discussed.     

Gender differences in posttraumatic stress disorder

One of the most consistent findings in the epidemiology of posttraumatic stress disorder (PTSD) is the higher risk of this disorder in women. Explanations reviewed within a psychobiological model of PTSD suggest that women's higher PTSD risk may be due to the type of trauma they experience, their younger age at the time of trauma exposure, their stronger perceptions of threat and loss of control, higher levels of peri-traumatic dissociation, insufficient social support resources, and greater use of alcohol to manage trauma-related symptoms like intrusive memories and dissociation, as well as gender-specific acute psychobiological reactions to trauma. This review demonstrates the need for additional research of the gender differences in posttraumatic stress. Recommendations are made for clinical practice.     

Associations between lower order anxiety sensitivity dimensions and DSM-5 posttraumatic stress disorder symptoms

Anxiety sensitivity (AS), a well-established individual difference variable reflecting a tendency to fear bodily sensations associated with arousal, has been implicated in the development and maintenance of posttraumatic stress disorder (PTSD). Despite these associations, little research has examined the relations between AS subfactors (eg physical, cognitive, and social) and PTSD symptoms and none have examined these associations in the context of DSM-5 (Diagnostic Statistical Manual of Mental Disorders, Fifth Edition) PTSD clusters (ie intrusion, avoidance, negative alterations in cognitions/mood, and arousal). Participants included 50 veterans presenting to an outpatient Veteran Affairs Clinic for psychological services. Upon intake, veterans completed a brief battery of self-report questionnaires to assist with differential diagnosis and treatment planning. Results revealed unique associations between lower order AS dimensions, in particular the cognitive concerns dimension, and all four DSM-5 PTSD symptom clusters. Given the malleable nature of AS cognitive concerns, as well as the growing number of veterans in need of care, future research should determine the extent to which targeting this cognitive risk factor reduces PTSD symptom severity among veterans.     

Brain-imaging studies of posttraumatic stress disorder

Brain-imaging studies of posttraumatic stress disorder (PTSD) have rapidly increased in recent years. Structural studies have identified potential smaller volumes of the hippocampus of traumatized and/or PTSD subjects. Functional activation studies have implicated hyperactive or altered functioning of brain regions, such as the amygdala and the insula, and a failure to engage emotional regulatory structures, such as the medial prefrontal and anterior cingulate cortex. Recent neurochemical investigations have suggested that neuromodulatory systems (eg, gamma-aminobutyric acid, micro-opioid) may underlie these aberrant brain activation patterns. This article reviews the literature on structural, functional, and neurochemical brain-imaging studies of PTSD.     

Intrusive memories in depression and posttraumatic stress disorder

This study compared the stressors and consequent intrusive memories reported by matched samples of patients with posttraumatic stress disorder (PTSD) and major depression. Although intrusive memories were slightly more common among PTSD patients, both quantitative and qualitative measures revealed few differences between the groups. PTSD patients were more likely to have experienced personal illness or assault, and depressed patients family deaths and illness, and interpersonal events. Factor analysis of the associated emotions and memory characteristics suggested the existence of specific links between fear and reliving, and helplessness and out-of-body experiences. Possible inhibitory relationships between fear and sadness, and between guilt and anger, were also noted.     

Sustained attention in combat-related posttraumatic stress disorder

There is substantial evidence that PTSD patients have information processing abnormalities for stimuli that are highly relevant to the traumas they have endured. The goal of the present study was to examine whether this extends to neutral stimuli as well. Twenty-four male Vietnam combat veterans with PTSD were compared to fifteen normal male comparison subjects on their performance on a sensitive measure of sustained attention, the Continuous Performance Test-Identical Pairs version (CPT-IP). PTSD subjects did not differ from controls in their ability to discriminate target stimuli from background noise on the CPT. Additionally they performed as well as controls, even in the presence of external distraction. Thus, this study did not find a generalized deficit in attention associated with PTSD on the CPT-IP. Nevertheless, further clarification of the nature of the information processing disturbance in PTSD is warranted.     

World assumptions and combat-related posttraumatic stress disorder

The authors examined the association between (a) personal world assumptions and (b) combat stress reactions (CSRs), posttraumatic stress disorder (PTSD), and PTSD's course among three groups of Israeli veterans: 109 veterans who suffered from CSR on the battlefield, 98 decorated veterans, and 189 control participants. Participants completed standardized questionnaires that measured PTSD and world assumption. Both CSR and chronic PTSD were associated with lower levels of self-worth and beliefs about the benevolence of people. In addition, the authors found a linear association between self-worth perceptions and levels of mental status. The authors examined the results of the study considering the extraordinary characteristics and meaning of war.     

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.     

Epidemiology of trauma and posttraumatic stress disorder in Mexico

Prevalence rates of trauma and posttraumatic stress disorder (PTSD) were estimated from a probability sample of 2,509 adults from 4 cities in Mexico. PTSD was assessed according to Diagnostic and Statistical Manual of Mental Disorders (American Psychiatric Association, 1994) criteria using the Composite International Diagnostic Interview (CIDI; WHO, 1997). Lifetime prevalence of exposure and PTSD were 76% and 11.2%, respectively. Risk for PTSD was highest in Oaxaca (the poorest city), persons of lower socioeconomic status, and women. Conditional risk for PTSD was highest following sexual violence, but nonsexual violence and traumatic bereavement had greater overall impact because of their frequency. Of lifetime cases, 62% became chronic; only 42% received medical or professional care. The research demonstrates the importance of expanding the epidemiologic research base on trauma to include developing countries around the world.     

A cognitive model of posttraumatic stress disorder

Posttraumatic stress disorder (PTSD) is a common reaction to traumatic events. Many people recover in the ensuing months, but in a significant subgroup the symptoms persist, often for years. A cognitive model of persistence of PTSD is proposed. It is suggested that PTSD becomes persistent when individuals process the trauma in a way that leads to a sense of serious, current threat. The sense of threat arises as a consequence of: (1) excessively negative appraisals of the trauma and/or its sequelae and (2) a disturbance of autobiographical memory characterised by poor elaboration and contextualization, strong associative memory and strong perceptual priming. Change in the negative appraisals and the trauma memory are prevented by a series of problematic behavioural and cognitive strategies. The model is consistent with the main clinical features of PTSD, helps explain several apparently puzzling phenomena and provides a framework for treatment by identifying three key targets for change. Recent studies have provided preliminary support for several aspects of the model.