Miriam Lommen

Trauma and Posttraumatic Stress Disorder (PTSD) in Patients with Schizophrenia or Schizoaffective Disorder

Trauma and posttraumatic stress disorder (PTSD) have high prevalence among individuals with severe mental illness, such as schizophrenia or schizoaffective disorder. This study examined whether trauma and PTSD are under-detected in this population, and whether the cognitive theory of PTSD is applicable to these individuals. Traumatic experiences, PTSD symptoms and negative posttraumatic cognitions were directly measured with questionnaires, and compared to information obtained via chart-review. Results showed clear evidence of under-report of trauma and under-diagnosis of PTSD in patients’ charts. Furthermore, negative posttraumatic cognitions were positively related to PTSD symptom severity, supporting the cognitive model of PTSD. These findings underscore the importance of assessing trauma history as well as PTSD in the routine evaluation of patients with schizophrenia or schizoaffective disorder in outpatient clinical settings. Furthermore, the finding of negative posttraumatic cognitions suggests that the cognitive model of PTSD may be applicable to patients with schizophrenia or schizoaffective disorder.

Impaired fear inhibition learning predicts the persistence of symptoms of posttraumatic stress disorder (PTSD)

Recent cross-sectional studies have shown that the inability to suppress fear under safe conditions is a key problem in people with posttraumatic stress disorder (PTSD). The current longitudinal study examined whether individual differences in fear inhibition predict the persistence of PTSD symptoms. Approximately 2 months after deployment to Afghanistan, 144 trauma-exposed Dutch soldiers were administered a conditional discrimination task (AX+/BX-). In this paradigm, A, B, and X are neutral stimuli. X combined with A is paired with a shock (AX+ trials); X combined with B is not (BX- trials). Fear inhibition was measured (AB trials). Startle electromyogram responses and shock expectancy ratings were recorded. PTSD symptoms were measured at 2 months and at 9 months after deployment. Results showed that greater startle responses during AB trials in individuals who discriminated between danger (AX+) and safety (BX-) during conditioning, predicted higher PTSD symptoms at 2 months and 9 months post-deployment. The predictive effect at 9 months remained significant after controlling for critical incidents during previous deployments and PTSD symptoms at 2 months. Responses to AX+ or BX- trials, or discrimination learning (AX+ minus BX-) did not predict PTSD symptoms. It is concluded that impaired fear inhibition learning seems to be involved in the persistence of PTSD symptoms.

Psychosocial predictors of chronic Post-Traumatic Stress Disorder in Sri Lankan tsunami survivors.

This study aimed to determine whether psychological factors associated with Post-Traumatic Stress Disorder (PTSD) identified in Western samples generalize to low Social-Economical-Status (SES) populations in an underdeveloped Asian country. The study included 113 survivors of the 2004-tsunami on the south coast of Sri Lanka, recruited from 4 preschools and 10 villages for displaced persons. With logistic regressions the relations between interview-based PTSD diagnosis and psychological factors were assessed, controlling for putative confounders. Fifteen months post-trauma the prevalence of PTSD was 52.2%. Multivariate analyses indicated that negative interpretation of tsunami-memories was significantly (P<0.005) related to PTSD. Of the putative confounders, gender and (non-replaced) lost work equipment were related to current PTSD (P<0.05). The results indicate that the relation between negative interpretation of trauma memories and PTSD is quite universal, suggesting that interventions focusing on this factor may be important in treatment of tsunami survivors who are suffering from chronic PTSD.

The centrality of fear extinction in linking risk factors to PTSD: A narrative review.

Recent prospective studies in emergency services have identified impaired fear extinction learning and memory to be a significant predictor of Posttraumatic Stress Disorder (PTSD), complementing a wealth of cross-sectional evidence of extinction deficits associated with the disorder. Additional fields of research show specific risk factors and biomarkers of the disorder, including candidate genotypes, stress and sex hormones, cognitive factors, and sleep disturbances. Studies in mostly nonclinical populations also reveal that the aforementioned factors are involved in fear extinction learning and memory. Here, we provide a comprehensive narrative review of the literature linking PTSD to these risk factors, and linking these risk factors to impaired fear extinction. On balance, the evidence suggests that fear extinction may play a role in the relationship between risk factors and PTSD. Should this notion hold true, this review carries important implications for the improvement of exposure-based treatments, as well as strategies for the implementation of treatment.

A prospective study of pre-trauma risk factors for post-traumatic stress disorder and depression.

Background It is unclear which potentially modifiable risk factors best predict post-trauma psychiatric disorders. We aimed to identify pre-trauma risk factors for post-traumatic stress disorder (PTSD) or major depression (MD) that could be targeted with resilience interventions. Method Newly recruited paramedics (n = 453) were assessed for history of mental disorders with structured clinical interviews within the first week of their paramedic training and completed self-report measures to assess hypothesized predictors. Participants were assessed every 4 months for 2 years to identify any episodes of PTSD and MD; 386 paramedics (85.2%) participated in the follow-up interviews. Results In all, 32 participants (8.3%) developed an episode of PTSD and 41 (10.6%) an episode of MD during follow-up. In all but nine cases (2.3%), episodes had remitted by the next assessment 4 months later. At 2 years, those with episodes of PTSD or MD during follow-up reported more days off work, poorer sleep, poorer quality of life, greater burn-out; and greater weight-gain for those with PTSD. In line with theories of PTSD and depression, analyses controlling for psychiatric and trauma history identified several pre-trauma predictors (cognitive styles, coping styles and psychological traits). Logistic regressions showed that rumination about memories of stressful events at the start of training uniquely predicted an episode of PTSD. Perceived resilience uniquely predicted an episode of MD. Conclusions Participants at risk of developing episodes of PTSD or depression could be identified within the first week of paramedic training. Cognitive predictors of episodes of PTSD and MD are promising targets for resilience interventions.

Anger: Cause or Consequence of Posttraumatic Stress? A Prospective Study of Dutch Soldiers

Many studies have shown that individuals with posttraumatic stress disorder (PTSD) experience more anger over time and across situations (i.e., trait anger) than trauma-exposed individuals without PTSD. There is a lack of prospective research, however, that considers anger levels before trauma exposure. The aim of this study was to prospectively assess the relationship between trait anger and PTSD symptoms, with several known risk factors, including baseline symptoms, neuroticism, and stressor severity in the model. Participants were 249 Dutch soldiers tested approximately 2 months before and approximately 2 months and 9 months after their deployment to Afghanistan. Trait anger and PTSD symptom severity were measured at all assessments. Structural equation modeling including cross-lagged effects showed that higher trait anger before deployment predicted higher PTSD symptoms 2 months after deployment (β = .36), with stressor severity and baseline symptoms in the model, but not with neuroticism in the model. Trait anger at 2 months postdeployment did not predict PTSD symptom severity at 9 months, and PTSD symptom severity 2 months postdeployment did not predict subsequent trait anger scores. Findings suggest that trait anger may be a pretrauma vulnerability factor for PTSD symptoms, but does not add variance beyond the effect of neuroticism.

Sleep and treatment outcome in posttraumatic stress disorder: results from an effectiveness study

Most patients with posttraumatic stress disorder (PTSD) suffer from sleep problems. Concerns have been raised about possible detrimental effects of sleep problems on the efficacy of psychological treatments for PTSD. In this study, we investigated the relation of session‐to‐session changes in PTSD symptoms and sleep, and tested whether sleep problems predicted poorer short‐ and long‐term treatment outcome.

Changing for Better or Worse? Posttraumatic Growth Reported by Soldiers Deployed to Iraq

There has been increased interest in self-perceived posttraumatic growth, but few longitudinal studies have focused on its relationship with posttraumatic stress. Self-perceived growth is generally thought to facilitate adjustment, but some researchers have proposed that it reflects a dysfunctional coping strategy that impedes adjustment and leads to posttraumatic stress. In this prospective longitudinal study, we examined the relationship between self-perceived posttraumatic growth and stress. Participants were soldiers deployed to Iraq. They were tested before their deployment (N = 479) and again 5 months (n = 382; 80%) and 15 months (n = 331; 69%) after returning home. Cross-lagged panel analysis indicated that more perceived growth 5 months postdeployment was associated with more posttraumatic stress 15 months postdeployment, even after we controlled for stressor severity, posttraumatic stress at 5 months, and potential predeployment confounders (extraversion, neuroticism, and cognitive ability). Findings suggest that it may be counterproductive to promote perceived growth to enhance adjustment after traumatic events.

The experience of traumatic events disrupts the measurement invariance of a posttraumatic stress scale.

Studies that include multiple assessments of a particular instrument within the same population are based on the presumption that this instrument measures the same construct over time. But what if the meaning of the construct changes over time due to ones experiences? For example, the experience of a traumatic event can influence ones view of the world, others, and self, and may disrupt the stability of a questionnaire measuring posttraumatic stress symptoms (i.e., it may affect the interpretation of items). Nevertheless, assessments before and after such a traumatic event are crucial to study longitudinal development of posttraumatic stress symptoms. In this study, we examined measurement invariance of posttraumatic stress symptoms in a sample of Dutch soldiers before and after they went on deployment to Afghanistan (N = 249). Results showed that the underlying measurement model before deployment was different from the measurement model after deployment due to invariant item thresholds. These results were replicated in a sample of soldiers deployed to Iraq (N = 305). Since the lack of measurement invariance was due to instability of the majority of the items, it seems reasonable to conclude that the underlying construct of PSS is unstable over time if war-zone related traumatic events occur in between measurements. From a statistical point of view, the scores over time cannot be compared when there is a lack of measurement invariance. The main message of this paper is that researchers working with posttraumatic stress questionnaires in longitudinal studies should not take measurement invariance for granted, but should use pre- and post-symptom scores as different constructs for each time point in the analysis.

Susceptibility to long-term misinformation effect outside of the laboratory

Objective To test the effect of misinformation outside of the laboratory and to explore correlates of the effect, including arousal, cognitive ability, and neuroticism. Method About 2 months before deployment to Afghanistan, 249 soldiers enrolled in this study, which was embedded in a larger project. Two months after deployment, participants were interviewed about stressors on deployment and they received subtle misinformation about a fictional event on deployment. Seven months later, they were retested, and completed a questionnaire about events on deployment. Results At 9 months, a total of 26% of participants reported that they had experienced the fictional event, although 7 months earlier they said they had not experienced it. Logistic regression analyses revealed that lower cognitive ability and a combination of high arousal and more stressors on deployment were related to higher susceptibility to the misinformation effect. Conclusions Results suggest that information provided by another source may be incorporated into related autobiographical memory, particularly for individuals with lower cognitive ability, high arousal at the time of encoding the information and more related experiences.