The causes of delayed post-traumatic stress disorder (PTSD) are debated, and the validity of late-onset PTSD has been questioned.

We aimed to examine predictors of delayed PTSD in a community sample of survivors of a natural disaster.

Norwegian survivors of the 2004 Indian Ocean tsunami (n = 532) responded to a questionnaire at 6 and 24 months post-disaster. The questionnaire measured PTSD symptoms, recalled exposure and immediate stress responses to the disaster, recalled perceived life threat, personality dimensions, social support and other subsequent adverse life events.

When dichotomising PTSD symptom scores, 331 participants had low and 194 had high PTSD scores (early-onset PTSD) at 6 months. Of those with initially low scores, 43 (13.0%) had high symptom scores (delayed PTSD) at 24 months. The delayed PTSD group had a lower degree of initially assessed threat and witness experiences of death or suffering, lower immediate stress response and higher degree of memory inflation of perceived threat than the early-onset PTSD group. Among those with low PTSD scores at 6 months, onset of delayed PTSD was associated with neuroticism and memory inflation of life threat, but not with the degree of initially assessed disaster exposure or reports of subsequent adverse life events.

Lack of association between trauma exposure and delayed onset of PTSD symptoms casts doubt on whether the traumatic event is actually the primary causative factor for delayed PTSD. Our findings suggest that delayed PTSD may be a manifestation of personality factors and memory inflation of the severity of an event.

It has been suggested that countries with more resources and better healthcare have populations with a higher risk of post-traumatic stress disorder (PTSD). Norway is a high-income country with good public healthcare.

To examine lifetime trauma exposure and the point prevalence of PTSD in the general Norwegian population.

A survey was administered to a national probability sample of 5500 adults (aged ≥18 years). Of 4961 eligible individuals, 1792 responded (36%). Responders and non-responders did not differ significantly in age, gender or urban versus rural residence. Trauma exposure was measured using the Life Events Checklist for the DSM-5. PTSD was measured with the PTSD Checklist for the DSM-5. We used the DSM-5 diagnostic guidelines to categorise participants as fulfilling the PTSD symptom criteria or not.

At least one serious lifetime event was reported by 85% of men and 86% of women. The most common event categories were transportation accident and life-threatening illness or injury. The point prevalence of PTSD was 3.8% for men and 8.5% for women. The most common events causing PTSD were sexual and physical assaults, life-threatening illness or injury, and sudden violent deaths. Risk of PTSD increased proportionally with the number of event categories experienced.

High estimates of serious life events and correspondingly high rates of PTSD in the Norwegian population support the paradox that countries with more resources and better healthcare have higher risk of PTSD. Possible explanations are high expectations for a risk-free life and high attention to potential harmful mental health effects of serious life events.

None.

Perceived life threat is associated with post-traumatic stress disorder (PTSD). Still, it is not known whether perceived threat may be important for PTSD in people indirectly exposed to trauma.

To examine the prevalence of perceived life threat and the association with PTSD in individuals directly or indirectly exposed to terror.

Data are cross-sectional from a survey 10 months after the 2011 Oslo bombing. Perceived life threat was measured by the question: ‘How great do you think the danger was that you would die?’ scored on a five-point scale. PTSD was measured with the PTSD Checklist (PCL).

The retrospective belief that one's life was in great or overwhelming danger was reported by 65% and 22% of employees who had been present or not present, respectively, at the site of the bomb explosion (n = 1923). A high perceived life threat was associated with PTSD among those present (odds ratio (OR) = 5.7, 95% CI 1.9–16.9) and not present (OR = 5.2. 95% CI 3.0–9.0), even after adjusting for objective exposure, demographics and neuroticism.

Perceived life threat may play a central role in the development and maintenance of PTSD in people directly as well as indirectly exposed to terror. Moderating perceptions of having been in serious danger may be an appropriate approach to the prevention and treatment of PTSD.

We aimed to explore how perceived safety after terrorism is connected to views on security measures and emergency preparedness in a workplace setting.

Using a questionnaire-based, cross-sectional study of ministerial employees in Norway who were targeted in a terrorist attack in 2011 (n=3344), we investigated how employees’ perceived safety at work 9 to 10 months after the attack was associated with their perceptions of whether security measures were sufficiently prioritized at work, whether there had been sufficient escape and evacuation training, and whether they were confident with evacuation procedures.

We found strong evidence of increasing perceived safety at work the more employees believed security measures were sufficiently prioritized at work (partially confounded by post-traumatic stress disorder), and the better their knowledge of evacuation procedures (modified by gender and education).

The present study suggests that employers may enhance perceived safety at work for terror-exposed employees by showing a commitment to security measures and by ensuring employees know evacuation procedures well. More research is needed to investigate causality patterns behind the associations found in this cross-sectional study. (Disaster Med Public Health Preparedness. 2016;10:805–811)

Following adverse work conditions, health consequences can be explained by an imbalance between the effort made and the reward received. We investigated the association between extra effort, perceived reward, and post-traumatic stress disorder (PTSD). The Effort-Reward Imbalance Model was used to examine whether extra effort at work in the aftermath of a workplace-related terrorist attack affected the risk of PTSD and the effects of reward for extra effort from a leader or colleagues.

Cross-sectional data were collected 10 months after a terrorist attack in Norway in 2011. Out of 3520 Ministry employees invited, 1927 agreed to participate. Employees reported any extra effort performed as a result of the bomb explosion and any reward received from a leader or colleagues. PTSD was assessed with the PTSD Checklist.

Employees who reported extra effort displayed increased risk for PTSD (odds ratio [OR]=1.71, 95% confidence interval [CI]: 1.15-2.55, P=0.008). Perceived reward for extra effort from a leader was associated with lower risk for PTSD (OR=0.39, 95% CI: 0.23-0.64, P<0.001) but not perceived reward from colleagues.

Extra effort may increase the risk of PTSD, but reward from a leader may mitigate this effect. The Effort-Reward Imbalance Model appears to be an appropriate approach that may contribute to understanding of the etiology of work-related PTSD. (Disaster Med Public Health Preparedness. 2016;10:219–224)

Post-traumatic stress disorder (PTSD) diagnosis often depends on a retrospective, self-report of exposure to a life-threatening event.

To examine the stability of recalled perceived life threat in a community sample exposed to a distinct stressful event.

Five hundred and thirty-two Norwegian citizens who experienced the 2004 South-East Asia tsunami completed a self-report questionnaire 6 and 24 months post-disaster. The questionnaire measured perceived life-threat intensity, exposure, immediate stress response, psychopathology, personality dimensions, self-efficacy and social support.

Recalled threat intensity increased from 6 to 24 months (P <0.001). Recall amplification was associated with lack of PTSD symptom improvement (P < 0.05), but not with degree of exposure, immediate stress response, mood or stress symptoms, personality, self-efficacy or social support.

Recall amplification of perceived life threat from a single stressful event occurs in the general population, it may hinder PTSD symptom improvement and it questions the diagnostic validity of PTSD.

During October and November 2005, the National Norwegian Tsunami Support Association organized a journey to the disaster area for survivors. The aim of this study was to investigate whether the Tsunami affected the participants' psychological problems.

Twenty-nine adults and 19 children made the journey. Steps were taken to enable each individual to acquire an overall understanding of the catastrophic event. Various forms of antiphobic training were provided. At the end of the stay, 28 adults replied to a questionnaire. The questions concerned: (1) motives for traveling; (2) benefits experienced; (3) psychological problems before departure; and (4) problems at the end of the stay. Parents with children were asked to assess their children's psychological problems at the same points in time.

Considerable improvements in anxiety symptoms were reported and observed in both the adults and children. No certain cases of retraumatization occurred.

The improvements can be understood in the light of psychodynamic, cognitive, and behavioral theory approaches. The duration of the improvement in symptoms remains to be documented. There appears to be grounds for encouraging traumatized patients to return to a disaster area as part of the treatment process if they so wish.