Testing whether posttraumatic stress disorder and major depressive disorder are similar or unique constructs

The Comorbidity of PTSD and MDD: Implications for Clinical Practice and Future Research

The high prevalence of post-traumatic stress disorder (PTSD) and major depressive disorder (MDD) comorbidity is well established, with comorbidity rates often between 30 and 50%. However, despite the high prevalence of this comorbidity, very few researchers have explored specific treatments for individuals who present with comorbid PTSD and MDD. Further, there has not been explicit examination of the mechanisms through which MDD influences trauma-focused therapy. As individuals with comorbid PTSD and MDD often present with a more chronic course of impairment and in some instances, a more delayed response to treatment, the need for such research is imperative. It will be proposed that there is merit in targeting depression within the treatment of comorbid PTSD and MDD. Accordingly, in this article we review explanations for the high PTSD and MDD comorbid relationship and highlight variables likely to explain such comorbidity. Theoretical accounts for how depression impedes optimal recovery from PTSD and the associated empirical findings are illustrated. We consequently argue that there is a need to develop and test treatments that target both PTSD and MDD symptoms. Directions for future research are highlighted.

Gender differences in the long-term associations between posttraumatic stress disorder and depression symptoms: findings from the Detroit Neighborhood Health Study

OBJECTIVE

Posttraumatic stress disorder (PTSD) and depression are known to be highly comorbid. However, previous findings regarding the nature of this comorbidity have been inconclusive. This study prospectively examined whether PTSD and depression are distinct constructs in an epidemiologic sample, as well as assessed the directionality of the PTSD-depression association across time.

METHODS

Nine hundred and forty-two Detroit residents (males: n = 387; females: n = 555) were interviewed by phone at three time points, 1 year apart. At each time point, they were assessed for PTSD (using the PCL-C), depression (PHQ-9), trauma exposure, and stressful life events.

RESULTS

First, a confirmatory factor analysis showed PTSD and depression to be two distinct factors at all three waves of assessments (W1, W2, and W3). Second, chi-square analysis detected significant differences between observed and expected rates of comorbidity at each time point, with significantly more no-disorder and comorbid cases, and significantly fewer PTSD only and depression only cases, than would be expected by chance alone. Finally, a cross-lagged analysis revealed a bidirectional association between PTSD and depression symptoms across time for the entire sample, as well as for women separately, wherein PTSD symptoms at an early wave predicted later depression symptoms, and vice versa. For men, however, only the paths from PTSD symptoms to subsequent depression symptoms were significant.

CONCLUSIONS

Across time, PTSD and depression are distinct, but correlated, constructs among a highly-exposed epidemiologic sample. Women and men differ in both the risk of these conditions, and the nature of the long-term associations between them.

Developing zebrafish models relevant to PTSD and other trauma- and stressor-related disorders

While post-traumatic stress disorder (PTSD) and other trauma- and stress-related disorders (TSRDs) represent a serious societal and public health concern, their pathogenesis is largely unknown. Given the clinical complexity of TSRD development and susceptibility, greater investigation into candidate biomarkers and specific genetic pathways implicated in both risk and resilience to trauma becomes critical. In line with this, numerous animal models have been extensively used to better understand the pathogenic mechanisms of PTSD and related TSRD. Here, we discuss the rapidly increasing potential of zebrafish as models of these disorders, and how their use may aid researchers in uncovering novel treatments and therapies in this field.

Posttraumatic stress disorder and depressive symptoms: joined or independent sequelae of trauma?

OBJECTIVE

The nature of co-morbidity between posttraumatic stress disorder (PTSD) and depression has been the subject of much controversy. This study addresses this issue by investigating associations between probable PTSD and depressive symptoms in a prospective, longitudinal sample of combat veterans.

METHOD

Symptoms of PTSD and depression were assessed at 3 points of time (i.e., 1991, 2003, 2008) over a period of 17 years utilizing the PTSD Inventory and the SCL-90 (Derogatis, 1977). Two groups of combat veterans, 275 former prisoners of war (ex-POWs) and 219 matched combatants (controls), were assessed. Data were analyzed using descriptive statistics, latent variable modeling, and confirmatory factor analysis.

RESULTS

A series of χ(2) tests revealed that the prevalence proportions of depressive symptoms and probable PTSD were higher among ex-POWs compared to controls at all time points. The prevalence of depressive symptoms was higher than the prevalence of PTSD symptoms in both groups at the each of the times. Latent Trajectories Modeling (LTM) indicated that while ex-POWs' PTSD symptom severity increased over time, the severity of symptoms remained stable among controls. Parallel Process Latent Growth Modeling (PLGM) revealed a positive bi-directional relationship whereby PTSD symptoms mediated the affect of captivity on depressive symptoms and depressive symptoms mediated the affect of captivity on PTSD symptoms over time. Utilizing Confirmatory Factor Analysis (CFA), a single factor model emerged for depressive and PTSD symptoms.

CONCLUSION

The findings suggest that while depression and PTSD seem to be different long-term manifestations of traumatic stress, accounted for in part by the severity of the trauma, they both may be parts of a common general traumatic stress construct. Clinical and theoretical implications of these findings are discussed.

Hippocampal volume is inversely related to PTSD duration

Numerous imaging studies have reported smaller hippocampal volumes in patients with PTSD. To investigate whether decreased hippocampal volume is associated with PTSD chronicity, independent of age, we used hierarchical linear regression to examine the relationship between PTSD duration (estimated from the amount of time that had elapsed since the traumatic event; mean=17 years; range=6-36 years) and hippocampal volume, adjusting for age and other factors. Freesurfer version 4.5 was used to quantify the volumes of the hippocampus and the caudate nucleus, which served as a "control" region, from the 1.5T Magnetic Resonance Images (MRI) of 55 combat veterans (mean age 45±9 years) with chronic and current PTSD. PTSD duration was significantly associated with right hippocampal volume (β=-0.34, t=-2.40, P=0.02) after accounting for intracranial volume, age, gender (entered in the first step) and comorbidities (e.g., early life trauma, current major depression, history of substance abuse/dependence, psychotropic medication use, entered in the second step). This finding provides support for the potential neurotoxic effects of PTSD on hippocampal volume.

Inflamed by the flames? The impact of terrorism and war on immunity

The physiological impact on citizens of prolonged exposure to violence and conflict is a crucial, yet underexplored, issue within the political science and biology literature. We examined the effect of high levels of exposure to rocket and terrorist attacks on biological markers of immunity and inflammation in a sample of 92 Israelis. A stratified random sample of individuals was drawn from a pool of subjects in Israel who had previously been interviewed regarding their stress exposure and psychological distress during a period of active rocket and terrorist attacks. These individuals were reinterviewed and blood samples were collected to assess antibodies to cytomegalovirus (CMV antibodies) and C-reactive protein (CRP). Posttraumatic stress disorder (PTSD) was significantly related to CRP, β = .33, p = .034, with body mass index, depression, and exposure to terrorism included in the model. Depression scores were not significantly associated with CRP or CMV antibody levels. In contrast to the established convention that psychological distress is the sole outcome of terrorism exposure, these findings reveal that individuals exposed to terrorism experience higher levels of both PTSD/depression, and inflammation. This study has important ramifications for how policy makers and medical health professionals should formulate public health policies and medically treat individuals living in conflict zones.

Assessing impact of differential symptom functioning on post-traumatic stress disorder (PTSD) diagnosis

This article explores the generalizability of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) diagnostic criteria for post-traumatic stress disorder (PTSD) to various subpopulations. Besides identifying the differential symptom functioning (also referred to as differential item functioning [DIF]) related to various background variables such as gender, marital status and educational level, this study emphasizes the importance of evaluating the impact of DIF on population inferences as made in health surveys and clinical trials, and on the diagnosis of individual patients. Using a sample from the National Comorbidity Study-Replication (NCS-R), four symptoms for gender, one symptom for marital status, and three symptoms for educational level were significantly flagged as DIF, but their impact on diagnosis was fairly small. We conclude that the DSM-IV diagnostic criteria for PTSD do not produce substantially biased results in the investigated subpopulations, and there should be few reservations regarding their use. Further, although the impact of DIF (i.e. the influence of differential symptom functioning on diagnostic results) was found to be quite small in the current study, we recommend that diagnosticians always perform a DIF analysis of various subpopulations using the methodology presented here to ensure the diagnostic criteria is valid in their own studies.

Clinical assessment of PTSD in children with mild to borderline intellectual disabilities: a pilot study

OBJECTIVE

There are few studies regarding assessment and treatment of trauma-related disorders in people with intellectual disabilities (ID). The aims of this study were to determine (1) the feasibility of an adapted version of a post-traumatic stress disorder (PTSD)-clinical interview and (2) to what extent manifestation of PTSD in a sample of children with mild to borderline ID corresponds with four existing PTSD algorithms.

METHOD

Fifteen children who visited a special need school were interviewed.

RESULTS

In all children, the full interview could be completed. Potentially traumatic events (A1 criterion), and PTSD symptoms for children with mild to borderline ID were similar to those observed in children without ID.

CONCLUSIONS

The manifestation of PTSD in children with mild to borderline ID corresponds with the manifestation of PTSD in children without ID. The data provide no reason to broaden PTSD criterion A1 for children with mild to borderline ID.

DSM-5 PTSD's symptom dimensions and relations with major depression's symptom dimensions in a primary care sample

Existing literature indicates significant comorbidity between posttraumatic stress disorder (PTSD) and major depression. We examined whether PTSD's dysphoria and mood/cognitions factors, conceptualized by the empirically supported four-factor DSM-5 PTSD models, account for PTSD's inherent relationship with depression. We hypothesized that depression's somatic and non-somatic factors would be more related to PTSD's dysphoria and mood/cognitions factors than other PTSD model factors. Further, we hypothesized that PTSD's arousal would significantly mediate relations between PTSD's dysphoria and somatic/non-somatic depression. Using 181 trauma-exposed primary care patients, confirmatory factor analyses (CFA) indicated a well-fitting DSM-5 PTSD dysphoria model, DSM-5 numbing model and two-factor depression model. Both somatic and non-somatic depression factors were more related to PTSD's dysphoria and mood/cognitions factors than to re-experiencing and avoidance factors; non-somatic depression was more related to PTSD's dysphoria than PTSD's arousal factor. PTSD's arousal did not mediate the relationship between PTSD's dysphoria and somatic/non-somatic depression. Implications are discussed.

Regional cerebral volumes in veterans with current versus remitted posttraumatic stress disorder

We previously reported that hippocampal volume was associated with current, but not lifetime posttraumatic stress disorder (PTSD) symptom severity. In the present study, we test the hypothesis that like the hippocampus, the volumes of other brain regions previously implicated in PTSD, are also negatively related to current, but not lifetime PTSD symptom severity. One hundred ninety-one veterans underwent structural magnetic resonance imaging (MRI) on a 4T scanner. Seventy-five veterans were trauma unexposed, 43 were trauma exposed without PTSD, 39 were trauma exposed with current PTSD, and 34 were trauma exposed veterans with remitted PTSD. Hippocampal, amygdala, rostral and caudal anterior cingulate, insula, and corpus callosum volumes, quantified with Freesurfer version 4.5, were analyzed by group using multivariate analysis of covariance. Veterans with PTSD had smaller hippocampal, caudal anterior cingulate, insula, and corpus callosum volumes than the unexposed controls (p≤0.009); smaller hippocampal, caudal anterior cingulate, insula (p≤0.009) and marginally smaller corpus callosum (p=0.06) than veterans with remitted PTSD; and smaller hippocampal and caudal anterior cingulate volumes than veterans without PTSD (p≤0.04). In contrast, there was no significant volume differences between veterans with remitted PTSD compared to those without PTSD or unexposed controls. The finding that current but not lifetime PTSD accounts for the volumes of multiple brain regions suggests that either smaller brain volume is a vulnerability factor that impedes recovery from PTSD or that recovery from PTSD is accompanied by a wide-spread restoration of brain tissue.

Exposure to interpersonal trauma, attachment insecurity, and depression severity

BACKGROUND

Exposure to traumatic events is a nonspecific risk factor for psychiatric symptoms including depression. The trauma-depression link finds support in numerous studies; however, explanatory mechanisms linking past trauma to current depressive symptoms are poorly understood. This study examines the role that attachment insecurity plays in mediating the relationship between prior exposure to trauma and current expression of depression severity.

METHODS

Past trauma and attachment anxiety and avoidance were assessed at baseline in a large cohort (N=705) of adults admitted to a specialized adult psychiatric hospital with typical lengths of stay ranging from 6 to 8 weeks. Depression severity was assessed at day 14 of treatment using the Beck Depression Inventory-II.

RESULTS

Interpersonal trauma (e.g., assaults, abuse) was correlated with depression severity, whereas exposure to impersonal trauma (e.g., natural disasters, accidents) was not. Adult attachment partially mediated the relationship between past interpersonal trauma and depression severity at day 14 among psychiatric inpatients.

LIMITATIONS

Measure of trauma exposure did not systematically differentiate the age of exposure or relationship to the perpetrator. Individuals scoring high on the self-report attachment measure may be prone to over-report interpersonal traumas.

CONCLUSIONS

Treatment of depression in traumatized patients should include an assessment of attachment insecurity and may be fruitful target for intervention.

Posttraumatic stress disorder diagnostic criteria and suicidal ideation in a South African Police sample

OBJECTIVE

Exposure to traumatic events may precipitate suicidal ideation. Once an individual is diagnosed with PTSD, a suicide risk assessment often follows. This study explores how PTSD symptom criteria correlate with suicidal ideation in a sample of police officers. While the psychometric measures of PTSD often mirror the DSM-IV-TR criteria, focusing on exposure, symptom, and duration criteria, suicidal ideation measures often focus on concepts quite different from that. In this report the focus was on investigating how PTSD symptom criteria correlate with the suicidal ideation.

METHOD

A group of South African police officers (N = 217) were assessed by means of the Posttraumatic Diagnostic Scale and a short version of the Adult Suicide Ideation Questionnaire. Linear and hierarchical regressions were used to determine which PTSD symptom criteria best predict suicidal ideation.

RESULTS

Hyperarousal was the primary predictor of suicidal ideation (R(2) [adjusted] = 0.249). Intrusive thoughts added only marginally to the model, contributing a further 2.5% to the declared variance. The contributions of the other two symptom types were negligible.

CONCLUSION

In this study hyperarousal correlated significantly with suicidal ideation. It is suggested that practitioners be alert to these symptoms as possible indicators of suicidal ideation. Implications for suicide risk assessment and prevention measures are discussed.

Brief treatment of co-occurring post-traumatic stress and depressive symptoms by use of accelerated resolution therapy(®)

This uncontrolled prospective cohort study evaluated the use of accelerated resolution therapy (ART) for treatment of comorbid symptoms of post-traumatic stress disorder (PTSD) and major depressive disorder. Twenty-eight adult subjects, mean age of 41 years (79% female, 36% Hispanic), received a mean of 3.7 ± 1.1 ART treatment sessions (range 1-5). ART is a new exposure-based psychotherapy that makes use of eye movements. Subjects completed a range of self-report psychological measures before and after treatment with ART including the 17-item PCL-C checklist (symptoms of PTSD) and 20-item Center for Epidemiologic Studies Depression Scale (CES-D). For the PCL-C, the pre-ART mean (±standard deviation) was 62.5 (8.8) with mean reductions of -29.6 (12.5), -30.1 (13.1), and -31.4 (14.04) at post-ART, 2-month, and 4-month follow-up, respectively (p < 0.0001 for comparisons to pre-ART score). Compared to pre-ART status, this corresponded to standardized effect sizes of 2.37, 2.30, and 3.01, respectively. For the CES-D, the pre-ART mean was 35.1 (8.8) with mean reductions of -20.6 (11.0), -18.1 (11.5), and -15.6 (14.4) at post-ART, 2-month, and 4-month follow-up, respectively (p ≤ 0.0001 compared to Pre-ART score). This corresponded to standardized effect sizes of 1.88, 1.58, and 1.09, respectively. Strong correlations were observed at 2-month and 4-month follow-up for post-treatment changes in PTSD and depression symptom scores (r = 0.79, r = 0.76, respectively, p ≤ 0.0002). No serious treatment-related adverse effects were reported. In summary, ART appears to be a promising brief, safe, and effective treatment for adults with clinically significant comorbid symptoms of PTSD and depression. Future controlled and mechanistic studies with this emerging therapy are warranted, particularly given its short treatment duration, and in light of current heightened emphasis on health care cost constraints.

Relations between the underlying dimensions of PTSD and major depression using an epidemiological survey of deployed Ohio National Guard soldiers

BACKGROUND

In the present study, the authors investigated the relationship between the underlying symptom dimensions of posttraumatic stress disorder (PTSD) and dimensions of major depressive disorder (MDD).

METHOD

A sample of 1266 Ohio National Guard soldiers with a history of overseas deployment participated and were administered the PTSD Checklist (assessing PTSD) and Patient Health Questionnaire-9 (assessing depression).

RESULTS

Using confirmatory factor analysis, results demonstrated that both PTSD's dysphoria and hyperarousal factors were more related to depression's somatic than non-somatic factor. Furthermore, depression's somatic factor was more related to PTSD's dysphoria than hyperarousal factor.

LIMITATIONS

Limitations of this study include the use of self-report measures and a predominately male military sample.

CONCLUSIONS

Results indicate that PTSD's dysphoria factor is related to depression specifically by way of depression's somatic construct. Given PTSD's substantial dysphoria/distress component, these results have implications for understanding the nature of PTSD's high comorbidity with depression.

Amygdala volume changes in posttraumatic stress disorder in a large case-controlled veterans group

CONTEXT

Smaller hippocampal volumes are well established in posttraumatic stress disorder (PTSD), but the relatively few studies of amygdala volume in PTSD have produced equivocal results.

OBJECTIVE

To assess a large cohort of recent military veterans with PTSD and trauma-exposed control subjects, with sufficient power to perform a definitive assessment of the effect of PTSD on volumetric changes in the amygdala and hippocampus and of the contribution of illness duration, trauma load, and depressive symptoms.

DESIGN

Case-controlled design with structural magnetic resonance imaging and clinical diagnostic assessments. We controlled statistically for the important potential confounds of alcohol use, depression, and medication use.

SETTING

Durham Veterans Affairs Medical Center, which is located in proximity to major military bases.

PATIENTS

Ambulatory patients (n = 200) recruited from a registry of military service members and veterans serving after September 11, 2001, including a group with current PTSD (n = 99) and a trauma-exposed comparison group without PTSD (n = 101).

MAIN OUTCOME MEASURE

Amygdala and hippocampal volumes computed from automated segmentation of high-resolution structural 3-T magnetic resonance imaging.

RESULTS

Smaller volume was demonstrated in the PTSD group compared with the non-PTSD group for the left amygdala (P = .002), right amygdala (P = .01), and left hippocampus (P = .02) but not for the right hippocampus (P = .25). Amygdala volumes were not associated with PTSD chronicity, trauma load, or severity of depressive symptoms.

CONCLUSIONS

These results provide clear evidence of an association between a smaller amygdala volume and PTSD. The lack of correlation between trauma load or illness chronicity and amygdala volume suggests that a smaller amygdala represents a vulnerability to developing PTSD or the lack of a dose-response relationship with amygdala volume. Our results may trigger a renewed impetus for investigating structural differences in the amygdala, its genetic determinants, its environmental modulators, and the possibility that it reflects an intrinsic vulnerability to PTSD.

Changes in facets of mindfulness and posttraumatic stress disorder treatment outcome

Though there has been a recent surge of interest in the relations between facets of mindfulness and Posttraumatic Stress Disorder (PTSD), there has been a dearth of empirical studies investigating the impact of changes in facets of mindfulness on PTSD treatment outcomes. The present study tested the prospective associations between pre- to post-treatment changes in facets of mindfulness and PTSD and depression severity at treatment discharge, among 48 military Veterans in residential PTSD treatment adhering to a cognitive-behavioral framework. Together, changes in facets of mindfulness significantly explained post-treatment PTSD and depression severity (19-24% of variance). Changes in acting with awareness explained unique variance in post-treatment PTSD severity and changes in nonjudgmental acceptance explained unique variance in post-treatment depression severity. These results remained significant after adjusting for shared variance with length of treatment stay.

Sleep quality among U.S. military veterans with PTSD: a factor analysis and structural model of symptoms

Poor sleep quality among individuals with posttraumatic stress disorder (PTSD) is associated with poorer prognosis and outcomes. The factor structure of the most commonly employed measure of self-reported sleep quality, the Pittsburgh Sleep Quality Index (PSQI), has yet to be evaluated among individuals with PTSD. The current study sought to fill this gap among a sample of 226 U.S. military veterans with PTSD (90% with co-occurring mood disorders, 73.5% with substance use disorders). We evaluated the factor structure of the PSQI by conducting an exploratory factor analysis (EFA) in approximately half of the sample (n = 111). We then conducted a second EFA in the other split half (n = 115). Lastly, we conducted a path analysis to investigate the relations between sleep factors and PTSD symptom severity, after accounting for the relation with depression. Results suggested sleep quality can best be conceptualized, among those with PTSD, as a multidimensional construct consisting of 2 factors, Perceived Sleep Quality and Efficiency/Duration. After accounting for the association between both factors and depression, only the Perceived Sleep Quality factor was associated with PTSD (β = .51). The results provide a recommended structure that improves precision in measuring sleep quality among veterans with PTSD.

Comparing the symptoms of posttraumatic stress disorder with the distress and fear disorders

New theoretical models of mood and anxiety disorders have been proposed to better understand the relations and patterns leading to their high diagnostic comorbidities. These models have highlighted two new groupings of the disorders, focused on the prevalence of fear and distress symptoms. The present study investigated the fit of the symptoms of posttraumatic stress disorder (PTSD) in these new models. The relations between the two primary sets of symptom scales of PTSD and the diagnoses of other comorbid disorders were examined in a large multisite sample of veterans from primary care clinics. The results suggested that there was no reliable difference in the predictive power of any of the PTSD symptom scales across the two diagnostic groups. New transdiagnostic models, assessment practices, and treatment approaches may provide better understanding of symptom overlap and diagnostic comorbidity in PTSD and related disorders.

Symptom overlap in posttraumatic stress disorder and major depression

Over the past decade there has been consistent criticism of the diagnostic criteria of posttraumatic stress disorder (PTSD) because of its high comorbidity with other mental disorders. Part of the problem surrounding PTSD may be related to the heterogeneity of its symptoms. In fact, recent research has identified a subset of PTSD symptoms, including symptoms of numbing and dysphoria, that may explain much of the overlap between PTSD and major depressive disorder (MDD). The present study sought to extend prior work by investigating the various subsets of PTSD symptoms in individuals from all four diagnostic combinations of PTSD and MDD (no MDD-PTSD, MDD-only, PTSD-only, and comorbid MDD-PTSD). Consenting participants completed diagnostic interviews and were categorized into the four groups. Based on responses to a self-report measure of PTSD symptoms, participants with no MDD-PTSD reported the least severe symptoms while the participants with comorbid MDD-PTSD reported the most severe symptoms. Interesting, participants in the MDD-only and PTSD-only groups consistently reported similar scores across all PTSD symptom scales. These findings further highlight the problematic diagnostic criteria and comorbidity in PTSD and emphasize the need to incorporate transdiagnostic treatment practices that focus on the overlapping symptoms, rather than specific diagnostic categories.

Moderation of adult depression by the serotonin transporter promoter variant (5-HTTLPR), childhood abuse and adult traumatic events in a general population sample

The impact of the promoter polymorphisms of the serotonin transporter (5-HTTLPR) on mood has been studied by two-way interaction models comprising one environmental factor and genotype variants. However, childhood abuse is assumed to be associated with different psychobiological long-term effects than adult traumatic events. Both types of trauma may interact on an individual basis throughout the lifespan moderating the impact of the 5-HTTLPR s allele on depressive disorders. Therefore, the hypothesis of a three-way interaction among the 5-HTTLPR, childhood abuse and adult traumatic experience was tested. Caucasian subjects (1,974) from the general population in Germany (Study of Health in Pomerania (SHIP)) were analyzed. Depressive symptoms were measured with the Beck Depression Inventory (BDI-II). Childhood abuse was assessed with the Childhood Trauma Questionnaire. Adult traumatic events were derived from the SCID interview (DSM-IV) on posttraumatic stress disorder (PTSD). Global three-way interactions among the 5-HTTLPR, adult traumatic experiences and childhood abuse (P = 0.0007) were found. Carriers of the ss or sl genotypes who had been exposed to childhood abuse and to more than two adult traumatic events had higher mean BDI-II scores (16.0 [95% CI 8.4-23.6]) compared to those carrying the ll genotype (7.6 [4.5-10.7]). These results were supported using a second, more severe definition of childhood abuse (P = 0.02). No two-way interactions were observed (P > 0.05). Childhood abuse and adult traumatic events may act synergistically in interaction with the s allele of the 5-HTTLPR to increase the risk for depressive symptoms independently from the lifetime diagnosis of PTSD.

Longitudinal linkages between depressive and posttraumatic stress symptoms in adolescent survivors following the Wenchuan earthquake in China: A three-wave, cross-lagged study

This study aimed to determine the relationships between depressive and posttraumatic stress disorder (PTSD) symptoms in a sample of adolescent survivors following the Wenchuan earthquake in China. Two-hundred adolescent survivors were reviewed at 12, 18 and 24-months post-earthquake. Depression and PTSD were assessed by two self-report questionnaires: The revised Center for Epidemiologic Studies Depression Scale for Children and the Revised Child PTSD Symptom Scale, respectively. The cross-lagged structural equation analysis with latent variables indicated that the PTSD symptoms and depression could be considered as two distinct and high-correlated constructs, and depression symptomatology pre-event could predict post-event PTSD. Depression symptoms play a crucial role in the development of PTSD symptoms. Implications of the results for psychological service providers to children and youth are discussed.

The structure of posttraumatic psychopathology in veterans attending primary care

This study attempted to extend research indicating that posttraumatic stress disorder (PTSD) factors of Re-experiencing, Avoidance and Hyperarousal are more related to Fear/phobic disorders, while PTSD Dysphoria is more related to Anxious-Misery disorders. Trauma exposure, PTSD and comorbidity data for 668 veteran patients were analysed using confirmatory factor analyses and relative strengths of the relationships between PTSD factors and the Fear and Anxious-Misery factors were assessed. Combining Simms, Watson, and Doebbeling's (2002) model of PTSD symptoms and Krueger's (1999) Fear/Anxious Misery model of mood and anxiety disorders fit the data well. Contrary to previous research, PTSD Re-experiencing, Avoidance and Hyperarousal did not correlate more with the Fear factor; nor did PTSD Dysphoria correlate more with Anxious-Misery. Hyperarousal was more closely related to Fear than was Re-experiencing; however, Avoidance was not. Dysphoria was more closely related to the Anxious-Misery factor than all other PTSD factors.

Posttraumatic stress disorder in DSM-5: estimates of prevalence and symptom structure in a nonclinical sample of college students

We empirically investigated recent proposed changes to the posttraumatic stress disorder (PTSD) diagnosis for DSM-5 using a non-clinical sample. A web survey was administered to 585 college students using the Stressful Life Events Screening Questionnaire to assess for trauma exposure but with additions for the proposed traumatic stressor changes in DSM-5 PTSD. For the 216 subjects endorsing previous trauma exposure and nominating a worst traumatic event, we administered the original PTSD Symptom Scale based on DSM-IV PTSD symptom criteria and an adapted version for DSM-5 symptoms, and the Center for Epidemiological Studies-Depression Scale. While 67% of participants endorsed at least one traumatic event based on DSM-IV PTSD's trauma classification, 59% of participants would meet DSM-5 PTSD's proposed trauma classification. Estimates of current PTSD prevalence were .4-1.8% points higher for the DSM-5 (vs. the DSM-IV) diagnostic algorithm. The DSM-5 symptom set fit the data very well based on confirmatory factor analysis, and neither symptom set's factors were more correlated with depression.