Daniel S. Weiss

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.

Impact of Event Scale: A Cross-Validation Study and Some Empirical Evidence Supporting a Conceptual Model of Stress Response Syndromes.

Conducted a cross-validational study on the Impact of Event Scale (IES), a self-report instrument assessing the essential characteristics associated with stress disorders. 35 bereaved outpatients completed the IES before entering time-limited dynamic psychotherapy and at 4 and 12 mo following termination. A further 28 Ss, not participating in therapy, completed the measure at similar intervals. Results confirm the scales relevance, internal consistency, and sensitivity. In addition, data are interpreted as consistent with a clinically derived theoretical model of the pattern of response to serious life events. As predicted by the theory, the syndromatic group showed greater intensity of intrusive and avoidance states; the relevant salience of reported experience was similar across groups; and the syndromatic group before intervention was characterized by an absence of a movement toward completion of processing the meaning of the event. (11 ref) (PsycINFO Database Record (c) 2012 APA, all rights reserved)

Problems in families of male Vietnam veterans with posttraumatic stress disorder

Interviews were conducted with a nationally representative sample of 1,200 male Vietnam veterans and the spouses or co-resident partners of 376 of these veterans. The veteran interview contained questions to determine the presence of posttraumatic stress disorder (PTSD) and items tapping family and marital adjustment, parenting problems, and violence. The spouse or partner (S/P) interview assessed the S/Ps view of these items, as well as her view of her own mental health, drug, and alcohol problems and behavioral problems of school-aged children living at home. Compared with families of male veterans without current PTSD, families of male veterans with current PTSD showed markedly elevated levels of severe and diffuse problems in marital and family adjustment, in parenting skills, and in violent behavior. Clinical implications of these findings are discussed.

Predicting symptomatic distress in emergency services personnel.

This study identified predictors of symptomatic distress in emergency services (EMS) personnel exposed to traumatic critical incidents. A replication was performed in 2 groups: 154 EMS workers involved in the 1989 Interstate 880 freeway collapse during the San Francisco Bay area earthquake, and 213 counterparts from the Bay area and from San Diego. Evaluated predictors included exposure, social support, and psychological traits. Replicated analyses showed that levels of symptomatic distress were positively related to the degree of exposure to the critical incident. Level of adjustment was also related to symptomatic distress. After exposure, adjustment, social support, years of experience on the job, and locus of control were controlled, 2 dissociative variables remained strongly predictive of symptomatic response. The study strengthens the literature linking dissociative tendencies and experiences to distress from exposure to traumatic stressors.

The prevalence of lifetime and partial post-traumatic stress disorder in vietnam theater veterans

A complete understanding of the consequences of service in a war zone includes examining the lifetime and current prevalence of post-traumatic stress disorder (PTSD), and of partial PTSD. Cases of partial PTSD are persons who have clinically significant symptoms of PTSD, but who do not meet the full diagnostic criteria. The National Vietnam Veterans Readjustment Study (NVVRS) estimated the lifetime prevalence of PTSD to be 30.9% among male theater veterans, 26.% among females; lifetime prevalence of partial PTSD was an additional 22.5% and 21.2%, respectively; current prevalence of partial PTSD was 11.1% in males and 7.8% in females. NVVRS findings indicate that of the 1.7 million veterans who ever experienced significant symptoms of PTSD after the Vietnam war, approximately 830,000 (49%) still experience clinically significant distress and disability from symptoms of PTSD. The contribution of partial PTSD represents an estimated additional 350,000 veterans.

Stress responses of emergency services personnel to the loma prieta earthquake interstate 880 freeway collapse and control traumatic incidents

A three-group quasi-experimental design contrasted the responses of rescue workers to the 1989 Loma Prieta earthquake Interstate 880 freeway collapse (n = 198) with responses to critical incident exposure of Bay Area Controls (n = 140) and San Diego Controls (n = 101). The three groups were strikingly similar with respect to demographics and years of emergency service. The I-880 group reported higher exposure, greater immediate threat appraisal, and more sick days. The three groups did not differ on current symptoms. For the sample as a whole EMT/Paramedics reported higher peritraumatic dissociation compared with Police. EMT/Paramedics and California road workers reported higher symptoms compared with Police and Fire personnel. Nine percent of the sample were characterized as having symptom levels typical of psychiatric outpatients. Compared with lower distress responders, those with greater distress reported greater exposure, greater peritraumatic emotional distress, greater peritraumatic dissociation, greater perceived threat, and less preparation for the critical incident.

Decreased hippocampal N-acetylaspartate in the absence of atrophy in posttraumatic stress disorder

BACKGROUND Previous magnetic resonance imaging studies of posttraumatic stress disorder reported hippocampal volume loss. The goals of this study were 1) to determine the relationship between hippocampal atrophy and posttraumatic stress disorder in the absence of alcohol abuse, and 2) to test if loss of N-acetylaspartate (a neuron marker) in the hippocampus of posttraumatic stress disorder occurs separate from atrophy. In addition, volume changes in the entorhinal cortex were also explored. METHODS Eighteen male patients with combat-related posttraumatic stress disorder (mean age 51.2 +/- 2.5 years) and 19 male control subjects (mean age 51.8 +/- 3.2 years) were studied using magnetic resonance imaging and Proton magnetic resonance spectroscopic imaging. Both groups had no alcohol and drug abuse during the past 5 years. RESULTS Posttraumatic stress disorder and control subjects had similar volumes of hippocampus and entorhinal cortex. In contrast to volume, N-acetylaspartate was significantly reduced by about 23% bilaterally in the hippocampus of posttraumatic stress disorder when compared with control subjects, and creatine-containing compounds were reduced by 26% in the right hippocampus of posttraumatic stress disorder. CONCLUSIONS N-acetyl asparate and creatine reductions imply that there are hippocampal abnormalities in posttraumatic stress disorder. Furthermore, these metabolite changes seem to be better indicators of posttraumatic stress disorder pathology than volume losses.

Longitudinal course and predictors of continuing distress following critical incident exposure in emergency services personnel

This study examines the longitudinal course and predictors of stress-specific and general symptomatic distress in emergency services personnel. A three-group quasi-experimental design was used to determine the responses of 322 rescue workers to the Loma Prieta earthquake Interstate 880 Freeway collapse and to unrelated control critical incidents. Self-report questionnaires, including measures of incident exposure, peritraumatic dissociation and emotional distress, and current symptoms, were administered 1.9 years (initial) and 3.5 years (follow-up) after the freeway collapse. Despite modest symptom improvement at follow-up, rescue workers were at risk for chronic symptomatic distress after critical incident exposure. Peritraumatic dissociation accounted for significant increments in current posttraumatic stress disorder symptoms, over and above exposure, adjustment, years of experience, locus of control, social support, and general dissociative tendencies. The results suggest that rescue workers, particularly those with more catastrophic exposure and those prone to dissociate at the time of the critical incident, are at risk for chronic symptomatic distress.

Predictors of Posttraumatic Stress in Police and Other First Responders

Abstract:  We provide an overview of previous research conducted by our group on risk and resilience factors for PTSD symptoms in police and other first responders. Based on our work, the findings of other investigators on individual differences in risk for PTSD, and drawing on preclinical studies fear conditioning and extinction, we propose a conceptual model for the development of PTSD symptoms emphasizing the role of vulnerability and resilience to peritraumatic panic reactions. We tested this conceptual model in a cross‐sectional sample of police officers (n= 715). Utilizing an hierarchical linear regression model we were able to explain 39.7% of the variance in PTSD symptoms. Five variables remained significant in the final model; greater peritraumatic distress (β= 0.240, P < .001), greater peritraumatic dissociation (β= 0.174, P < .001), greater problem‐solving coping (β= 0.103, P < .01), greater routine work environment stress (β= 0.182, P < .001), and lower levels of social support (β=−0.246, P < .001). These results were largely consistent with the proposed conceptual model. Next steps in this line of research will be to test this model prospectively in a sample of 400 police academy recruits assessed during training and currently being followed for the first 2 years of police service.

The prevalence of post-traumatic stress disorder in the Vietnam generation: A multimethod, multisource assessment of psychiatric disorder

Findings from the Congressionally mandated National Vietnam Veterans Readjustment Study indicate that nearly one-half million Vietnam veterans—15.2% of the men and 8.5% of the women who served in Vietnam—suffer from post-traumatic stress disorder (PTSD) fifteen or more years after their military service. Current PTSD prevalence rates for Vietnam veterans are significantly and substantially higher than the rates for their comparable Vietnam generation peers, which range from 0.3% to 2.5%. Additionally, the current prevalence rate among male Vietnam veterans was found to differ significantly among race/ethnicity subgroups: 27.9% among Hispanic men, 20.6% among black men, 13.7% among white/other men. Multivariate analyses indicated that although background factors are significantly related to the current prevalence of PTSD, the current prevalence is much higher among Vietnam veterans than among era veteran and civilian counterpart comparison groups even after background differences are taken into account. These analyses also demonstrated the important role of exposure to combat and other types of war zone stress in the current prevalence of the disorder.