Emergence Of Posttraumatic Stress Disorder Research Articles

7TH INTERNATIONAL SYMPOSIUM “SMART LION”. REHABILITATION IN UKRAINE, SEPTEMBER 26, 2023

The seventh international symposium, SMART LION, was held on September 26, 2023. It was to celebrate the 150th anniversary of the Shevchenko Scientific Society and the 125th anniversary of the Medical Commission. The topics concerned the challenges our country faces today. Organizers of SMART LION 2023 are Professors Valentyna Chopyak, Oksana Zayachkivska, and Vassyl Lonchyna. They managed to gather almost two hundred participants offline and over a thousand guests online.
 Olena Lazareva, Vira Rokoshevska, Oleh Bilianskyi, Oksana Hdyria, and Oleh Fitkalo delivered their reports on the development of rehabilitation in Ukraine and its main avenues.
 The emergence of post-traumatic stress disorder (PTSD) is a critical challenge for contemporary Ukraine and has long been a significant obstacle for global medicine. That is the reason why Oleh Berezyuk, Head of the Mental Health Service of the UNBROKEN National Rehabilitation Center, brought up the matter of difficulties in correctly diagnosing and treating PTSD in the context of a multidisciplinary hospital, while Professor Valentyna Chopyak and MD Svitlana Zubchenko focused the attention of attendees on PTSD immune-rehabilitation.
 During the concluding block of the symposium, which focused on the contemporary interpretation of physical therapy and occupational therapy, as well as interprofessional education, communication, and cooperation, attendees were afforded the chance to listen to highly intriguing reports presented by Renata Roman (Canada), Ellen Godwin (USA), Karl J. Sandin (USA), David Omut (USA), and Oksana Zayachkivska (Ukraine, USA).
 The scientific event concluded with a round table on the future of physical therapy and rehabilitation in Ukraine, with its outcomes leading to the resolution of the seventh international symposium, SMART LION 2023.

Threat Appraisal, Recovery Operations, and PTSD Symptoms Among US Air Force Rescue Personnel.

Research among military personnel and veterans indicates that subjective appraisal of warzone stressors explains the relation of combat exposure to posttraumatic stress disorder (PTSD), but not the relation of exposure to injury and death to PTSD. Studies have primarily been limited to conventional forces using aggregate measures of warzone stressor exposure. Threat appraisal may play a different role in the emergence of PTSD among military personnel for whom dangerous deployment experiences are more closely associated with exposure to injury and death, such as US Air Force Pararescuemen and Combat Rescue officers. In a sample of 207 rescue personnel, correlations among various types of warzone stressor exposure, threat appraisal, and postdeployment PTSD symptoms were examined. The relative strongest correlates of threat appraisal were stressors related to injury, death, and human remains. Although exposure to these stressors was also correlated with PTSD symptom severity, partial correlations of stressor exposure and PTSD symptoms were no longer significant when adjusting for threat appraisal. Results support the contributing role of threat appraisal to PTSD among military personnel whose primary duties entail exposure to injury and death under hostile and dangerous conditions.

The GluA1-Related BDNF Pathway Is Involved in PTSD-Induced Cognitive Flexibility Deficit in Attentional Set-Shifting Tasks of Rats.

Background: Post-Traumatic Stress Disorder (PTSD) is a severe psychological disorder characterized by intrusive thoughts, heightened arousal, avoidance, and flashbacks. Cognitive flexibility dysfunction has been linked with the emergence of PTSD, including response inhibition deficits and impaired attentional switching, which results in difficulties for PTSD patients when disengaging attention from trauma-related stimuli. However, the molecular mechanisms of cognitive flexibility deficits remain unclear. Methods: The animals were exposed to a single prolonged stress and electric foot shock (SPS&S) procedure to induce PTSD-like features. Once the model was established, the changes in cognitive flexibility were assessed using an attentional set-shifting task (ASST) in order to investigate the effects of traumatic stress on cognitive flexibility. Additionally, the molecular alterations of certain proteins (AMPA Receptor 1 (GluA1), brain-derived neurotrophic factor (BDNF), and Postsynaptic density protein 95 (PSD95) in the medial prefrontal cortex (mPFC) were measured using Western blot and immunofluorescence. Results: The SPS&S model exhibited PTSD-like behaviors and induced reversal learning and set-shifting ability deficit in the ASST. These behavioral changes are accompanied by decreased GluA1, BDNF, and PSD95 protein expression in the mPFC. Further analysis showed a correlative relationship between the behavioral and molecular alterations. Conclusions: The SPS&S model induced cognitive flexibility deficits, and the potential underlying mechanism could be mediated by GluA1-related BDNF signaling in the mPFC.

Cognitive-Emotional Aspects of Post-Traumatic Stress Disorder in the Context of Female Genital Mutilation.

Around 200 million women and girls worldwide are affected by female genital mutilation/cutting (FGM/C). FGM/C is a procedure that harms or alters the external female genitals for non-medical reasons, and is usually performed on children. Often, this procedure leads to severe consequences for the women’s physical and mental health. In a cross-sectional sample of 112 women seeking medical counseling, physical and mental health characteristics associated with FGM/C were examined and possible predictors for the development of post-traumatic stress disorder (PTSD) in women affected by FGM/C were identified. A total of 55.4% (n = 66) of the women reported symptom levels of probable PTSD. Predictors for higher PTSD symptomology were an older age at the time of the FGM/C procedure, feelings of guilt and the centrality of the event in the woman’s life. Thus, cognitive–emotional processing was found to play an important role in the emergence of PTSD in women suffering from FGM/C. However, interventions taking into consideration these characteristics are mostly lacking and need to be investigated further in the context of FGM/C.

Assessment on risk and stress of resident doctors during the COVID-19 pandemic.

It has been noted that post-traumatic stress disorder symptoms could be common in physicians who have experienced a traumatic event. The aim of this study was to determine the prevalence of post-traumatic stress disorder and contributing risk factors among resident doctors working in a tertiary care hospital during the COVID-19 pandemic. A cross-sectional study was conducted via an online survey from May to July 2020. Sociodemographic characteristics, exposure to the coronavirus, application of personal hygiene rules, presence and use of personal protective equipment, anxiety and prevalence of post-traumatic stress disorder were investigated. In total, 17.8% (n = 40) of 225 resident doctors who participated in the study had post-traumatic stress disorder. Working at a department serving to COVID-19 patients increased the risk of post-traumatic stress disorder by 2.9 times (OR = 2.936, p = 0.003) while contacting positive patients increased this risk by 2.6 times (OR = 2.607, p = 0.023) and lack of personal protective equipment by 3.6 times (OR = 3.656, p = 0.018). Anxiety scores were statistically significantly higher in women, married and those living with their parents or spouses and children (p = 0.049; p = 0.011; p = 0.004, respectively). Working in a department serving to COVID-19 patients, contact with positive patients and lack of personal protective equipment were risk factors in the emergence of post-traumatic stress disorder in resident doctors. Anxiety was also found to be greater in women, married and those living with their families.

715 Insomnia as a Risk for PTSD During the COVID-19 Pandemic

IntroductionThe COVID-19 pandemic and associated attempts to curb its spread have led to a significant increase in mental health issues. Evidence suggests that sleep provides a protective resilience against the adverse effects of stress. Moreover, sleep disruption is often considered the “hallmark symptom” of posttraumatic stress disorder (PTSD). Here we hypothesized that insomnia would increase during the first six months of the pandemic, and that higher insomnia would be associated with elevated rates of PTSD.MethodsA total of 6,190 adults ranging in age from 18 to 84 years (53.6% female), completed an online cross-sectional survey at one of six time points between April and September 2020 (~1,000 per administration). Instruments included the Insomnia Severity Index (ISI), Primary Care PTSD Checklist (PC-PTSD), and the PTSD Checklist-5 (PCL-5). Standard clinical cutoffs were used for ISI (≥10) and PCL-5 (≥38). Data were analyzed with analysis of variance, chi-square contingency tables, and bivariate correlations.ResultsOver the first six-months of the pandemic, PTSD increased with each passing month on both the PC-PTSD (p=.001) and PCL-5 (p<.0001). Similarly, ISI scores increased month-by-month (p<.0002). Insomnia scores were highly correlated with PCL-5 PTSD scores (r=.62, p<.0001), even when sleep items on the scale were excluded (r=.60, p<.0001). Finally, the rate of PTSD remained below 5% across all months for those without insomnia, but among those with insomnia, the prevalence of PTSD increased between May (26% positive) and September (40% positive), representing an increase of 56% over the data collection period (interaction p=.0004).ConclusionBoth insomnia and PTSD have increased dramatically over the first six months of the COVID-19 pandemic. Moreover, insomnia appears to be highly linked with the emergence of PTSD during this time. While it is not possible to make causal attributions from these cross-sectional findings, the steadily increasing rates of PTSD over time only among those with insomnia, raise the possibility that sleep disruption could act as a diathesis for the development of PTSD symptoms in response to the pandemic. Addressing insomnia during the pandemic may be an important aspect of maintaining psychological resilience in the populace.Support (if any):

The Sequential Relation Between Changes in Catastrophizing and Changes in Posttraumatic Stress Disorder Symptom Severity.

Catastrophizing has been discussed as a cognitive precursor to the emergence of posttraumatic stress disorder (PTSD) symptoms following the experience of stressful events. Implicit in cognitive models of PTSD is that treatment-related reductions in catastrophizing should yield reductions in PTSD symptoms. The tenability of this prediction has yet to be tested. The present study investigated the sequential relation between changes in a specific form of catastrophizing-symptom catastrophizing-and changes in PTSD symptom severity in a sample of 73 work-disabled individuals enrolled in a 10-week behavioral activation intervention. Measures of symptom catastrophizing and PTSD symptom severity were completed at pre-, mid-, and posttreatment assessment points. Cross-sectional analyses of pretreatment data revealed that symptom catastrophizing accounted for significant variance in PTSD symptom severity, β = .40, p < .001, sr = .28 (medium effect size), even when controlling for known correlates of symptom catastrophizing, such as pain and depression. Significant reductions in symptom catastrophizing and PTSD symptoms were observed during treatment, with large effect sizes, ds = 1.42 and 0.94, respectively, ps < .001. Cross-lagged analyses revealed that early change in symptom catastrophizing predicted later change in PTSD symptoms; early changes in PTSD symptom severity did not predict later change in symptom catastrophizing. These findings are consistent with the conceptual models that posit a causal relation between catastrophizing and PTSD symptom severity. The clinical implications of the findings are discussed.

Pre- and postnatal alcohol exposure delays, in female but not in male rats, the extinction of an auditory fear conditioned memory and increases alcohol consumption.

Repeated exposure to alcohol increases retrieval of fear-conditioned memories, which facilitates, among other factors, the emergence of post-traumatic stress disorder (PTSD). Individuals with PTSD are more likely to develop alcohol and substance abuse related disorders. We assessed if prenatal and early postnatal alcohol exposure (PAE) increased the susceptibility to retain aversive memories and if this was associated with subsequent heightened alcohol consumption. Pregnant Sprague-Dawley rats were exposed for 22hr/day, throughout pregnancy and until postnatal Day 7 to a single bottle of sucralose - sweetened 10% alcohol solution (PAE Group), or to a single bottle of tap water and sucralose (Control Group). Auditory fear conditioning (AFC) was performed in the adolescent offspring at postnatal Day 40. Freezing was measured during acquisition, retention and extinction phases, followed by 3weeks of free choice alcohol intake. Female, but not male, PAE rats exhibited impaired extinction of the aversive memory, a finding associated with higher levels of 3-4 Dihidroxyphenylacetic acid (DOPAC) in the nucleus accumbens and heightened alcohol intake, respect to controls. These findings suggest that PAE makes females more vulnerable to long-term retention of aversive memories, which coexist with heightened alcohol intake. These findings are reminiscent of those of PTSD.

Headaches in Moria: a reflection on mental healthcare in the refugee camp population of Lesbos.

Having returned from a period of volunteering with a healthcare charity working with the refugee camp population of Lesbos in Greece, a junior doctor reflects on the common presentations he saw and the current state of mental healthcare for these patients. The placement of already-traumatised people in an overcrowded and under-resourced camp environment creates a perfect storm for the emergence of post-traumatic stress disorder, depression and anxiety. With extremely limited psychiatric care in place, he considers the simple interventions he could use to help his patients with their distressing symptoms. This prompts exploration of the importance of giving time to listen as well as encouraging small but significant lifestyle changes. After exploring the ethics of psychiatric diagnosis in this setting, the author concludes that while we must acknowledge the political origins of some of the symptomatology in this population, we must continue to strive to treat psychiatric illness with all the appropriate interventions available to us in order to help those in this patient group recover and move forward.

Revictimization as a high-risk factor for development of posttraumatic stress disorder: a systematic review of the literature.

Objective:Much research has been published on the role of sexual revictimization in the emergence of mental disorders in adulthood, but findings have sometimes been contradictory. The present systematic review sought to assess the state of the evidence on revictimization as a potential factor for the emergence of posttraumatic stress disorder (PTSD).Methods:Electronic searches were conducted in five databases (MEDLINE/PubMed, Cochrane Library, Campbell Library, PsycINFO, and LILACS), using the terms PTSD, posttraumatic stress disorder, child abuse, and rape.Results:We identified nine articles that established a connection among childhood sexual abuse (CSA), sexual revictimization in adulthood, and development of PTSD. Eight of the nine papers included were classified as having strong methodological quality (grade VI). One was classified as IV, with an average quality-of-evidence rating. The mean methodological quality score of the articles was 5.5, and the quality of evidence was deemed strong.Conclusion:In the included studies, PTSD symptoms were most prevalent in the CSA + adult sexual assault groups, providing further evidence for the revictimization hypothesis.

Trauma et culture : influence des facteurs culturels dans la rencontre traumatique et perspectives psychothérapeutiques

It exists a very strong interpersonal variability of psychological and psychiatric consequences after a trauma. In the present article, we suggest exploring the cultural dimension, its influence in the traumatic process and the potential emergence of Post-Traumatic Stress Disorder, and the importance of its taking into consideration during the victims’ psychotherapeutic care. Individual ecology is linked with collective ecology of the community, in its rites and traditions, its lifestyle, its system of representations and values, and its spirituality. An event then turns out to be traumatic for an individual according to the meaning given to this life experience, estimated through the prism of cultural codes it has integrated and which are part of its subjective life. However, it would seem that the hegemonic western models of evaluation and diagnose post-traumatic disorders do not integrate enough the cultural characteristics, as well as recent psychotherapies forms.

Acute and Chronic Posttraumatic Stress Symptoms in the Emergence of Posttraumatic Stress Disorder

Little is understood about how the symptoms of posttraumatic stress develop over time into the syndrome of posttraumatic stress disorder (PTSD). To use a network analysis approach to identify the nature of the association between PTSD symptoms in the acute phase after trauma and the chronic phase. A prospective cohort study enrolled 1138 patients recently admitted with traumatic injury to 1 of 4 major trauma hospitals across Australia from March 13, 2004, to February 26, 2006. Participants underwent assessment during hospital admission (n = 1388) and at 12 months after injury (n = 852). Networks of symptom associations were analyzed in the acute and chronic phases using partial correlations, relative importance estimates, and centrality measures of each symptom in terms of its association strengths, closeness to other symptoms, and importance in connecting other symptoms to each other. Data were analyzed from March 3 to September 5, 2016. Severity of PTSD was assessed at each assessment with the Clinician-Administered PTSD Scale. Of the 1138 patients undergoing assessment at admission (837 men [73.6%] and 301 women [26.4%]; mean [SD] age, 37.90 [13.62] years), strong connections were found in the acute phase. Reexperiencing symptoms were central to other symptoms in the acute phase, with intrusions and physiological reactivity among the most central symptoms in the networks in terms of the extent to which they occur between other symptoms (mean [SD], 1.2 [0.7] and 1.0 [0.9], respectively), closeness to other symptoms (mean [SD], 0.9 [0.3] and 1.1 [0.9], respectively), and strength of the associations (mean [SD], 1.6 [0.3] and 1.5 [0.3] respectively) among flashbacks, intrusions, and avoidance of thoughts, with moderately strong connections between intrusions and nightmares, being upset by reminders, and physiological reactivity. Intrusions and physiological reactivity were central in the acute phase. Among the 852 patients (73.6%) who completed the 12-month assessment, overall network connectivity was significantly stronger at 12 months than in the acute phase (global strength values, 6.57 vs 7.60; paired difference, 1.03; P < .001). The network associations among the reexperiencing symptoms were strengthened at 12 months, and physiological reactivity was strongly associated with the startle response, which was also associated with hypervigilance. Strong connectivity among emotional numbing, detachment from others, and disinterest in activities as well as moderately strong links among irritability (anger), concentration deficits, and sleep disturbance were found. As time elapses after trauma, fear circuitry and dysphoric PTSD symptoms appear to emerge as connected networks. Intrusive memories and reactivity are centrally associated with other symptoms in the acute phase, potentially pointing to the utility of addressing these symptoms in early intervention strategies.

Posttraumatic Stress Disorder: Structural Characterization with 3-T MR Imaging.

Purpose To explore cerebral alterations related to the emergence of posttraumatic stress disorder (PTSD) by using three-dimensional T1-weighted imaging and also to explore the relationship of gray and white matter abnormalities and the anatomic changes with clinical severity and duration of time since the trauma. Materials and Methods Informed consent was provided, and the prospective study was approved by the ethics committee of the West China Hospital. Recruited were 67 patients with PTSD and 78 adult survivors without PTSD 7-15 months after a devastating earthquake in western China. All participants underwent magnetic resonance (MR) imaging with a 3-T imager to obtain anatomic images. Cortical thickness and volumes of 14 subcortical gray matter structures and five subregions of the corpus callosum were analyzed with software. Statistical differences between patients with PTSD and healthy survivors were evaluated with a general linear model. Averaged data from the regions with volumetric or cortical thickness differences between groups were extracted in each individual to examine correlations between morphometric measures and clinical profiles. Results Patients with PTSD showed greater cortical thickness in the right superior temporal gyrus, inferior parietal lobule, and left precuneus (P < .05; Monte Carlo null-z simulation corrected) and showed reduced volume in the posterior portion of the corpus callosum (F = 6.167; P = .014) compared with healthy survivors of the earthquake. PTSD severity was positively correlated with cortical thickness in the left precuneus (r = 0.332; P = .008). The volumes of posterior corpus callosum were negatively correlated with PTSD ratings in all survivors (r = -0.210; P = .013) and with cortical thickness of the left precuneus in patients with PTSD (r = -0.302; P = .017). Conclusion Results indicate that patients with PTSD had alterations in both cerebral gray matter and white matter compared with individuals who experienced similar psychologic trauma from the same stressor. Importantly, early in the course of PTSD, gray matter changes were in the form of increased, not decreased, cortical thickness, which may have resulted from neuroinflammatory or other trophic process related to endocrine changes or functional compensation. (©) RSNA, 2016.

5-HTTLPR genotype potentiates the effects of war zone stressors on the emergence of PTSD, depressive and anxiety symptoms in soldiers deployed to iraq.

Exposure to war zone stressors is common, yet only a minority of soldiers experience clinically meaningful disturbance in psychological function. Identification of biomarkers that predict vulnerability to war zone stressors is critical for developing more effective treatment and prevention strategies not only in soldiers but also in civilians who are exposed to trauma. We investigated the role of the serotonin transporter linked polymorphic region (5-HTTLPR) genotype in predicting the emergence of post-traumatic stress disorder (PTSD), depressive and anxiety symptoms as a function of war zone stressors. A prospective cohort of 133 U.S. Army soldiers with no prior history of deployment to a war zone, who were scheduled to deploy to Iraq, was recruited. Multilevel regression models were used to investigate associations between 5-HTTLPR genotype, level of war zone stressors, and reported symptoms of PTSD, depression and anxiety while deployed to Iraq. Level of war zone stressors was associated with symptoms of PTSD, depression and anxiety. Consistent with its effects on stress responsiveness, 5-HTTLPR genotype moderated the relationship between level of war zone stressors and symptoms of emotional disturbance. Specifically, soldiers carrying one or two low functioning alleles (S or LG ) reported heightened symptoms of PTSD, depression and anxiety in response to increased levels of exposure to war zone stressors, relative to soldiers homozygous for the high functioning allele (LA ). These data suggest that 5-HTTLPR genotype moderates individual sensitivity to war zone stressors and the expression of emotional disturbance including PTSD symptoms. Replication of this association along with identification of other genetic moderators of risk can inform the development of biomarkers that can predict relative resilience vs. vulnerability to stress.

Mobbing in Slovenia: Prevalence, Mobbing Victim Characteristics, and the Connection with Post-Traumatic Stress Disorder

Abstract An increasing number of organizations face the problem of mobbing, which represents a serious, widespread problem with numerous consequences for victims, organizations, and society. We also recognize the connection this phenomenon has with the emergence of post-traumatic stress disorder (PTSD). PTSD poses one of the most critical consequences for victims of mobbing, who mostly consist of employees at lower organizational levels. Our research focuses on the prevalence of mobbing in Slovenia, its correlation to PTSD, and some differences in the subjective and objective assessments of being exposed to mobbing. We found that the prevalence of mobbing in Slovenia can be compared to some previous assessments as well as data from other countries. Among the study's participants, 24% could be classified as regular victims of mobbing. For the first time, we link mobbing with PTSD using a Slovenian sample. We also recorded some interesting differences between subjective and objective assessments of mobbing, thereby indicating the importance of subjective conceptualizations of mobbing acts, which should be investigated in greater detail in future research.

تأثير العلاج الواقعي في خفض اضطرابات ما بعد الضغوط الصدمية لدى طلاب المرحلة المتوسطة

تأثير العلاج الواقعي في خفض اضطرابات ما بعد الضغوط الصدمية لدى طلاب المرحلة المتوسطة

Ameliorating intrusive memories of distressing experiences using computerized reappraisal training.

The types of appraisals that follow traumatic experiences have been linked to the emergence of posttraumatic stress disorder (PTSD). Could changing reappraisals following a stressful event reduce the emergence of PTSD symptoms? The present proof-of-principle study examined whether a nonexplicit, systematic computerized training in reappraisal style following a stressful event (a highly distressing film) could reduce intrusive memories of the film, and symptoms associated with posttraumatic distress over the subsequent week. Participants were trained to adopt a generally positive or negative poststressor appraisal style using a series of scripted vignettes after having been exposed to highly distressing film clips. The training targeted self-efficacy beliefs and reappraisals of secondary emotions (emotions in response to the emotional reactions elicited by the film). Successful appraisal induction was verified using novel vignettes and via change scores on the post traumatic cognitions inventory. Compared with those trained negatively, those trained positively reported in a diary fewer intrusive memories of the film during the subsequent week, and lower scores on the Impact of Event Scale (a widely used measure of posttraumatic stress symptoms). Results support the use of computerized, nonexplicit, reappraisal training after a stressful event has occurred and provide a platform for future translational studies with clinical populations that have experienced significant real-world stress or trauma.

Post-Traumatic Stress Disorder in Turkish Child and Adolescent Survivors Three Years after the Marmara Earthquake.

The study investigated the emergence of post-traumatic stress disorder (PTSD) symptoms in child and adolescent survivors in Turkey three years after the 1999 Marmara Earthquake, with consideration of the severity of exposure and the survivors' gender and age. A representative sample of 293 young earthquake survivors (152 female and 141 male between the ages of 8 and 15) participated in the study. Participants' scores on the Post-Traumatic Stress Disorder Reaction Index for Children indicated that 31.4% reported moderate, 24.2% reported severe, and 3.8% reported very severe traumatic stress reactions. Analysis of the Revised Impact of Events Scale for Children scores revealed that 56% reported severe PTSD symptoms. While severity of exposure and gender were significantly associated with severity of PTSD symptoms, age was not related to PTSD symptoms. The results indicated a high need for addressing the mental health problems of the child and adolescent trauma survivors in Turkey.

The relationship between childhood support and later emergence of PTSD

The authors examine the relationship between three sources of social support (maternal, paternal, and peer) and the development of posttraumatic stress disorder (PTSD). This study utilized data from the National Comorbidity Survey (NCS), a large (N = 5,877) nationally representative population survey. Persons with and without a lifetime history of PTSD and those with and without a history of trauma exposure were compared on levels of social support received prior to age 15. Persons with a history of PTSD reported that they received less maternal, paternal, and peer support as children than those without PTSD. Importantly, persons who developed PTSD after the age of 17 reported lower levels of early childhood support from their fathers.

Natural Course of Posttraumatic Stress Disorder

A 20-month prospective follow-up of survivors of the severe earthquake in Turkey in 1999 examined the natural course of posttraumatic stress disorder (PTSD) and the contribution of different symptom clusters to the emergence of PTSD. Subjects were randomly sampled in a suburb of Istanbul that was severely affected by the earthquake. A total of 464 adults were assessed with a self-report instrument for PTSD symptoms on 3 consecutive surveys that were administered 1 to 3, 6 to 10, and 18 to 20 months following the earthquake. The prevalence of PTSD was 30.2% on the first survey and decreased to 26.9% and 10.6% on the second and third surveys, respectively. Female subjects showed initially higher (34.8%) PTSD rates compared with male subjects (19.1%). However, gender differences disappeared by the time of the third survey due to high spontaneous remission rates in female subjects. Low levels of chronic and delayed-onset PTSD were observed. A major contribution of the avoidance symptoms to PTSD diagnosis was identified by statistical analysis. Initial PTSD following an earthquake may be as prevalent as in other natural disasters, but high rates of spontaneous remission lead to low prevalence 1.5 years following the earthquake. Initial avoidance characteristics play a major role in the emergence of PTSD.