Latent trajectories of trauma symptoms and resilience: the 3-year longitudinal prospective USPER study of Danish veterans deployed in Afghanistan

Low neuroticism as an indicator of resilience: a longitudinal study of Danish soldiers before, during and after deployment

Background: Posttraumatic stress disorder (PTSD) is a serious and debilitating condition among military veterans. Exposure to potentially traumatic events (PTEs) may lead to PTSD and PTE sensitivity may be influenced by the personality trait neuroticism.Objective: The current investigation aims to test whether exposure to PTEs during deployment is associated with changes in PTSD symptoms, and whether individual levels of neuroticism are related to resilience or sensitivity to such exposures.Methods: The study sample included 701 Danish soldiers deployed to Afghanistan in 2009. PTSD symptoms were measured pre-, peri- and post-deployment (T1-T3) with the PTSD Checklist-Civilian Version. PTSD symptom load was modelled in a mixed linear model along with an extensive list of covariates. Interactions between time, exposure, and neuroticism were tested in order to assess whether neuroticism moderated the effect of PTEs upon PTSD symptoms.Results: On average, PTSD symptoms decreased from T1 through T3. Factors associated with higher PTSD symptom levels included number of past trauma, neuroticism, and low age at deployment. Interaction analyses showed that individuals with low and medium neuroticism levels displayed no significant change in PTSD symptoms, and individuals with high neuroticism displayed a significant decrease in PTSD symptoms. These changes were consistent across levels of perceived exposure to danger and combat and witnessing the consequences of war.Conclusions: Results indicate that low levels of neuroticism appear to be related to resilience. Individuals with high levels of neuroticism displayed elevated PTSD symptoms across all time points, but contrary to expectations, they reported a significant decrease in PTSD symptoms from pre- to post-deployment.

Five-year trajectories of symptom severity, physical and mental functioning in patients with persistent somatic symptoms: the PROSPECTS cohort study

OBJECTIVES

Knowledge about the long-term course and prognosis of persistent somatic symptoms (PSS) is important to improve clinical decision-making and guidance for patients with PSS. Therefore, we aimed to: (1) identify distinct 5-year trajectories of symptom severity, physical and mental functioning in adult patients with PSS and (2) explore patient characteristics associated with these trajectories.

DESIGN

We used longitudinal data (seven measurements over a 5-year period) of the PROSPECTS study: a prospective cohort of adult patients with PSS. We applied Latent Class Growth Mixture Modelling to identify distinct trajectories for the three outcomes.

SETTING AND PARTICIPANTS

Patients were recruited in general practices and specialised treatment facilities for PSS throughout the Netherlands. The study population consisted of participants with three or more measurements available (n=297).

PRIMARY OUTCOME MEASURES

Symptom severity (Patient Health Questionnaire 15), physical and mental functioning (RAND-36 Physical Component Summary and Mental Component Summary).

RESULTS

For symptom severity, we identified two 'stable' trajectories: 'severe symptoms, stable' (15.8%) and 'moderate symptoms, stable' (84.2%). For physical functioning, we identified three trajectories: 'poor physical functioning, marked improvement' (8.5%); 'poor physical functioning, stable' (34.7%) and 'moderate physical functioning, slight improvement' (56.8%). For mental functioning, we identified three trajectories: 'poor mental functioning, marked improvement' (13.9%); 'moderate mental functioning, deterioration' (12.2%) and 'moderate mental functioning, slight improvement' (73.8%). Patients' characteristics such as personal, social and environmental background, illness stressors, comorbid diseases, cognitive, emotional and behavioural responses varied for the distinct trajectories.

CONCLUSIONS

We identified distinct 5-year trajectories for the three outcomes. Our findings suggest a high prevalence of persistence of symptoms and limited improvement in physical and mental functioning in the majority of patients with PSS. In a small proportion of patients, we identified trajectories that showed considerable physical or mental improvement or deterioration. Patient characteristics differed for the identified trajectories and may guide early recognition, although predictive studies are warranted.

Geographic Variation, Economic Activity, and Labor Market Characteristics in Trajectories of Suicide in the United States, 2008-2020

Suicide rates in the United States have increased over the past 15 years, with substantial geographic variation in these increases; yet there have been few attempts to cluster counties by the magnitude of suicide rate changes according to intercept and slope or to identify the economic precursors of increases. We used vital statistics data and growth mixture models to identify clusters of counties by their magnitude of suicide growth from 2008 to 2020 and examined associations with county economic and labor indices. Our models identified 5 clusters, each differentiated by intercept and slope magnitude, with the highest-rate cluster (4% of counties) being observed mainly in sparsely populated areas in the West and Alaska, starting the time series at 25.4 suicides per 100,000 population, and exhibiting the steepest increase in slope (0.69/100,000/year). There was no cluster for which the suicide rate was stable or declining. Counties in the highest-rate cluster were more likely to have agricultural and service economies and less likely to have urban professional economies. Given the increased burden of suicide, with no clusters of counties improving over time, additional policy and prevention efforts are needed, particularly targeted at rural areas in the West.

Recurrence of post-traumatic stress disorder: systematic review of definitions, prevalence and predictors

BACKGROUND

Many people will experience a potentially traumatic event in their lifetime and a minority will go on to develop post-traumatic stress disorder (PTSD). A wealth of literature explores different trajectories of PTSD, focusing mostly on resilient, chronic, recovered and delayed-onset trajectories. Less is known about other potential trajectories such as recurring episodes of PTSD after initial recovery, and to date there has been no estimate of what percentage of those who initially recover from PTSD later go on to experience a recurrence. This systematic review aimed to synthesise existing literature to identify (i) how 'recurrence' of PTSD is defined in the literature; (ii) the prevalence of recurrent episodes of PTSD; and (iii) factors associated with recurrence.

METHODS

A literature search of five electronic databases identified primary, quantitative studies relevant to the research aims. Reference lists of studies meeting pre-defined inclusion criteria were also hand-searched. Relevant data were extracted systematically from the included studies and results are reported narratively.

RESULTS

Searches identified 5,398 studies, and 35 were deemed relevant to the aims of the review. Results showed there is little consensus in the terminology or definitions used to refer to recurrence of PTSD. Because recurrence was defined and measured in different ways across the literature, and prevalence rates were reported in numerous different ways, it was not possible to perform meta-analysis to estimate the prevalence of recurrence. We also found no consistent evidence regarding predictors of PTSD recurrence.

CONCLUSION

A clear and consistent evidence-based definition of recurrence is urgently needed before the prevalence and predictors of recurrence can be truly understood.

Distinctively different human neurobiological responses after trauma exposure and implications for posttraumatic stress disorder subtyping

Trauma elicits various adaptive and maladaptive responses among all exposed people. There may be distinctively different patterns of adaptation/maladaptation or types according to neurobiological predisposition. The present study aims to dissect the heterogeneity of posttraumatic conditions in order to identify clinically meaningful subtypes in recently traumatized individuals and evaluate their neurobiological correlates and long-term prognosis. We implemented a data-driven classification approach in both discovery (n = 480) and replication (n = 220) datasets of trauma-exposed and trauma-unexposed individuals based on the clinical data across a wide range of assessments. Subtype-specific patterns of functional connectivity in higher-order cortical networks, longitudinal clinical outcomes, and changes in functional connectivity were also evaluated. We identified four distinct and replicable subtypes for trauma-exposed individuals according to posttraumatic stress symptoms. Each subtype was distinct in clinical characteristics, brain functional organization, and long-term trajectories for posttraumatic symptoms. These findings help enhance current understanding of mechanisms underlying the human-specific heterogeneous responses to trauma. Furthermore, this study contributes data towards the development of improved interventions, including targeting of subtype-specific characteristics, for trauma-exposed individuals and those with PTSD.

Mental health across the early years in the military

BACKGROUND

The mental health impact of the initial years of military service is an under-researched area. This study is the first to explore mental health trajectories and associated predictors in military members across the first 3-4 years of their career to provide evidence to inform early interventions.

METHODS

This prospective cohort study surveyed Australian Defence personnel (n = 5329) at four time-points across their early military career. Core outcomes were psychological distress (K10+) and posttraumatic stress symptoms [four-item PTSD Checklist (PCL-4)] with intra-individual, organizational and event-related trajectory predictors. Latent class growth analyses (LCGAs) identified subgroups within the sample that followed similar longitudinal trajectories for these outcomes, while conditional LCGAs examined the variables that influenced patterns of mental health.

RESULTS

Three clear trajectories emerged for psychological distress: resilient (84.0%), worsening (9.6%) and recovery (6.5%). Four trajectories emerged for post-traumatic stress, including resilient (82.5%), recovery (9.6%), worsening (5.8%) and chronic subthreshold (2.3%) trajectories. Across both outcomes, prior trauma exposure alongside modifiable factors, such as maladaptive coping styles, and increased anger and sleep difficulties were associated with the worsening and chronic subthreshold trajectories, whilst members in the resilient trajectories were more likely to be male, report increased social support from family/friends and Australian Defence Force (ADF) sources, and use adaptive coping styles.

CONCLUSIONS

The emergence of symptoms of mental health problems occurs early in the military lifecycle for a significant proportion of individuals. Modifiable factors associated with wellbeing identified in this study are ideal targets for intervention, and should be embedded and consolidated throughout the military career.

The evolution of PTSD symptoms in serving and ex-serving personnel of the UK armed forces from 2004 to 16: A longitudinal examination

Whilst most military personnel do not develop Post-Traumatic Stress Disorder (PTSD), ex-serving personnel exhibit higher levels compared to those in the military. The heterogeneity of symptom development for serving and ex-serving personnel has not yet been compared in the UK Armed Forces (UK AF). Latent class growth modelling was employed to estimate the trajectories of PTSD symptoms from three waves of data from the PTSD Checklist (PCL-C) from a UK AF sample (N = 7357). Regression mixture models were conducted to investigate covariates of class membership. Five trajectory classes were identified. Most of the sample reported no-low symptoms (71.3%). Of those reporting probable PTSD during the 12 year-period, 4.6% showed improvements, 4.9% worsened, and 1.8% displayed chronic symptoms. A class with subthreshold elevated symptoms (17.3%) was also identified. Trajectories of serving and ex-serving personnel were not substantially different, but more ex-serving personnel were symptomatic and those with chronic symptoms worsened over time. Chronic disorder was associated with lower rank, experiencing violent combat, and proximity to wounding/death on deployment. Worsening symptoms were associated with childhood stress/violence, lower rank, not being in a relationship, inconsistent post-deployment social support, proximity to wounding/death, and voluntary, or medical discharge. The present study found most UKAF personnel did not report PTSD symptoms between 2004 and 16 but, among those experiencing probable PTSD, more participants reported deteriorating/persistent symptoms than who improved. PTSD-onset was related to adversities across childhood and deployment, and lack of social support. Findings underscore the importance of addressing the through-life contributors of PTSD in order to prevent ingrained disorder.

Resting-state EEG functional connectivity predicts post-traumatic stress disorder subtypes in veterans

Objective. Post-traumatic stress disorder (PTSD) is highly heterogeneous, and identification of quantifiable biomarkers that could pave the way for targeted treatment remains a challenge. Most previous electroencephalography (EEG) studies on PTSD have been limited to specific handpicked features, and their findings have been highly variable and inconsistent. Therefore, to disentangle the role of promising EEG biomarkers, we developed a machine learning framework to investigate a wide range of commonly used EEG biomarkers in order to identify which features or combinations of features are capable of characterizing PTSD and potential subtypes.Approach. We recorded 5 min of eyes-closed and 5 min of eyes-open resting-state EEG from 202 combat-exposed veterans (53% with probable PTSD and 47% combat-exposed controls). Multiple spectral, temporal, and connectivity features were computed and logistic regression, random forest, and support vector machines with feature selection methods were employed to classify PTSD. To obtain robust results, we performed repeated two-layer cross-validation to test on an entirely unseen test set.Main results. Our classifiers obtained a balanced test accuracy of up to 62.9% for predicting PTSD patients. In addition, we identified two subtypes within PTSD: one where EEG patterns were similar to those of the combat-exposed controls, and another that were characterized by increased global functional connectivity. Our classifier obtained a balanced test accuracy of 79.4% when classifying this PTSD subtype from controls, a clear improvement compared to predicting the whole PTSD group. Interestingly, alpha connectivity in the dorsal and ventral attention network was particularly important for the prediction, and these connections were positively correlated with arousal symptom scores, a central symptom cluster of PTSD.Significance. Taken together, the novel framework presented here demonstrates how unsupervised subtyping can delineate heterogeneity and improve machine learning prediction of PTSD, and may pave the way for better identification of quantifiable biomarkers.

Suicide Ideation and Social Support Trajectories in National Guard and Reserve Servicemembers

Objective: Since 2004 increased rates of suicide have been noted in the US Armed Forces. We examined the association of social support (SS) trajectories and suicide ideation (SI) over a four-year period in Reserve Component (RC) servicemembers (National Guard and Reserve). We also examined baseline mental health measures, as predictors of the identified trajectories. Methods: Structured interviews were conducted with a nationally representative sample of 1,582 RC servicemembers at baseline and three follow-up waves. Latent growth mixture modeling identified SS trajectories and the association with follow-up SI. Multinomial logistic regression analyses were used to predict SS trajectories using baseline measures of demographics and mental health. Results: We identified four trajectories of SS and their associated prevalence of follow-up SI: low (n = 60, 3.8%; SI = 30.5%), medium (n = 229, 14.5%; SI = 14.1%), high-low (n = 66, 4.2%; SI = 13.6%), and high-high (n = 1,227, 77.5%; SI = 4.2%). There were significant differences in follow-up SI prevalence between each pair of SS trajectories except between the medium-SS and high-low-SS trajectories. Baseline SI, post-traumatic stress disorder (PTSD), depression, binge drinking, and mental health diagnosis were associated with increased likelihood of being on a low-SS or medium-SS trajectory. Baseline PTSD discriminated being on the high-high-SS and high-low-SS trajectories. Conclusion: Results support four trajectories of social support and that individuals with low or decreasing SS are likely to have greater follow-up SI. Baseline mental health assessments can identify these risk trajectories.

Time course of symptoms in posttraumatic stress disorder with delayed expression: A systematic review

OBJECTIVE

To examine the hypothesis that PTSD with delayed expression in some cases occurs without subthreshold PTSD symptoms above background levels bridging the gap between the traumatic exposure(s) and the clinical diagnosis.

METHODS

We performed systematic searches of peer-reviewed papers in English referenced in Pubmed, Embase, or PsycINFO and ascertained 34 prospective studies of PTSD symptom trajectories identified by latent class growth statistical modeling. Studies with delayed and low-stable trajectories provided appropriate data for this study. We computed the difference between the delayed trajectory PTSD symptom sumscore and the low-stable PTSD sumscore at the observed points in time after the traumatic event(s).

RESULTS

In 29 study populations, the latent class growth analyses displayed delayed trajectories, and in these, we identified 110 data points (% PTSD sumscore difference/months since traumatic exposure). The median PTSD symptom sumscore was 25% higher during the initial 6 months among individuals in the delayed trajectory compared to those in low-stable trajectory. From this level, the difference widened and reached a plateau of 40-50% higher. The variation was large, and the baseline participation rate and loss to follow-up were exceeding 25% in the majority of the studies. Heterogeneity of populations, measures, and analyses precluded formal meta-analysis.

CONCLUSION

Delayed PTSD is preceded by PTSD symptoms during the first year in most cases. Still, few individuals may experience an asymptomatic delay. The results underpin the rationale for monitoring PTSD symptoms and may inform forensic assessments in that delayed PTSD without symptoms bridging the traumatic event is rare.

Psychological risk factors that characterize acute stress disorder and trajectories of posttraumatic stress disorder after injury: a study using latent class analysis

Background

The course and different characteristics of acute and posttraumatic stress disorder (ASD, PTSD) in trauma populations are unclear.

Objective

The aims were to identify longitudinal trajectories of PTSD, to establish a risk profile for ASD and PTSD based on patients' sociodemographic, clinical, and psychological characteristics, and to study the effect of ASD and dissociation on PTSD during 12 months after trauma.

Method

Patients completed questionnaires after inclusion and at 3, 6, 9, and 12 months afterwards. Trajectories were identified using repeated measures latent class analysis (RMLCA). The risk profile was based on a ranking of importance of each characteristic using Cohen's d effect sizes and odds ratios. The impact of ASD and dissociation on PTSD was examined using logistic regression analyses.

Results

Altogether, 267 patients were included. The mean age was 54.0 (SD = 16.1) and 62% were men. The prevalence rate of ASD was approximately 21.7% at baseline, and 36.1% of trauma patients exhibited PTSD at 12 months after injury. Five trajectories were identified: (1) no PTSD symptoms, (2) mild, (3) moderate, (4) subclinical, and (5) severe PTSD symptoms. These trajectories seemed to remain stable over time. Compared with patients in other trajectories, patients with ASD and (subclinical) PTSD were younger and scored higher on anxiety, depressive symptoms, neuroticism, and trait anxiety. Regarding dissociation symptoms, inability to recall memories about the event was significantly more present than an altered sense of reality, (105 (40.7%) versus 56 (21.7%), p = .031), although that symptom had the strongest likelihood for PTSD. Patients with dissociation were significantly at risk for PTSD than patients without dissociation (OR = 4.82; 95%CI: 1.91-12.25).

Conclusions

Psychological factors characterized ASD and trajectories of PTSD during 12 months post-trauma. Healthcare providers who are aware of these findings could early identify patients at risk for ASD and PTSD and refer them for patient-centred interventions.

Changes in perceived social support and PTSD symptomatology among Danish army military personnel

PURPOSE

Previous research has identified social support to be associated with risk of posttraumatic stress disorder (PTSD) symptoms among military personnel. While the lack of social support influences PTSD symptomatology, it is unknown how changes in perceived social support affect the PTSD symptom level in the aftermath of deployment. Furthermore, the influence of specific sources of social support from pre- to post-deployment on level of PTSD symptoms is unknown. We aim to examine how changes in perceived social support (overall and from specific sources) from pre- to 2.5 year post-deployment are associated with the level of post-deployment PTSD symptoms.

METHODS

Danish army military personnel deployed to Afghanistan in 2009 and 2013 completed questionnaires at pre-deployment and at 2.5 year post-deployment measuring perceived social support and PTSD symptomatology and sample characteristics of the two cohorts. Data were analyzed using univariate and multivariate nominal logistic regression.

RESULTS

Negative changes in perceived social support from pre- to post-deployment were associated with both moderate (OR 1.99, CI 1.51-2.57) and high levels (OR 2.71, CI 1.94-3.78) of PTSD symptoms 2.5 year post-deployment (adjusted analysis). Broadly, the same direction was found for specific sources of social support and level of PTSD symptoms. In the adjusted analyses, pre-deployment perceived social support and military rank moderated the associations.

CONCLUSIONS

Deterioration in perceived social support (overall and specific sources) from pre- to 2.5 year post-deployment increases the risk of an elevated level of PTSD symptoms 2.5 year post-deployment.

Course and Predictors of Posttraumatic Stress Disorder in the Canadian Armed Forces: A Nationally Representative, 16-Year Follow-up Study: Cours et prédicteurs du trouble de stress post-traumatique dans les Forces armées canadiennes: une étude de suivi de 16 ans nationalement représentative

OBJECTIVE

This study examined baseline risk and protective predictors and interim correlates of the persistence/recurrence, remission, and onset of posttraumatic stress disorder (PTSD) in a 16-year prospective, nationally representative sample of Canadian Forces members and veterans.

METHODS

The 2018 Canadian Armed Forces Members and Veterans Mental Health Follow-up Survey is a prospective study of 2,941 regular force service members and veterans who participated in the 2002 Canadian Community Health Survey on Mental Health and Wellbeing: Canadian Forces Supplement (n = 5,155; ages 15 to 64 years; response rate 68%). PTSD diagnoses in 2002 and 2018 were used to create 4 groups: (1) no lifetime, (2) remitted, (3) new onset, and (4) persistent/recurrent PTSD. Multinomial regressions were conducted to identify predictors of PTSD courses.

RESULTS

Female sex, being a junior noncommissioned member (vs. officer), and land (vs. air) operations in 2002 were associated with all PTSD courses relative to no lifetime PTSD (relative risk ratio [RRR] range: 1.28 to 3.65). After adjusting for sociodemographic variables, baseline predictors of all PTSD courses included lifetime mental disorder, history of mental health care utilization, all trauma type categories (deployment-associated, sexual, "other"), and the number of lifetime traumatic events (RRR range: 1.14 to 8.95). New ("since 2002") traumas, transitioning to veteran status, and alcohol dependence were mostly associated with the new onset and persistent/recurrent PTSD courses (RRR range: 1.79 to 4.31), while mental health care utilization and greater avoidance coping were associated with all PTSD courses (RRR range: 1.10 to 17.87). Protective factors for several PTSD courses at one or both time points included social support, social network size, and problem-focused coping (RRR range: 0.71 to 0.98).

CONCLUSIONS

This is the first population-based survey to examine the longitudinal course of PTSD in Canadian Forces members. Prevention and intervention programs focused on bolstering social support and active coping strategies as possible protective factors/correlates may help mitigate the development and persistence of PTSD.

Posttraumatic growth and psychosocial gains from adversities of korean special forces: a consensual qualitative research

Because military special forces carry out dangerous missions, they are much more exposed to adversities and traumatic events compared to other occupational groups. According to Posttraumatic Growth theory, individuals tend to obtain positive growth through adversities. Moreover, a framework of Psychosocial Gains from Adversity argues not only individual changes but also social changes in the group to which the individual belongs are induced. Therefore, the present study aimed to explore the adverse experiences of special forces operatives and delineate the positive shift at an individual and social level via Consensual Qualitative Research (CQR). Eight individuals serving in special forces at the Korean Army, Navy and Air Force were interviewed using a semi-structured protocol. Four domains including 10 categories and 34 subcategories were identified: (a) Adverse experiences; (b) Personal change; (c) Social change; and (d) Attributes related to adverse experience. The findings and clinical implications are discussed in light of growth over facing adversities and interaction between personal and social factors.

Trajectories of PTSD and secondary traumatization: A longitudinal study

Ever since the publication of the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), there has been a controversy around whether the inclusion of indirect exposure as a potential traumatic event for the diagnosis of posttraumatic stress disorder (PTSD) is justified. The aim of the current study was to examine the validity of PTSD resulting from secondary traumatization by evaluating the longitudinal trajectories and clinical picture of PTSD following both direct exposure and indirect exposure to war trauma. One-hundred-and-fifty-five war veterans of the 1973 Yom Kippur War and their spouses filled out self-report questionnaires assessing PTSD, 30 (T1), 38 (T2), and 42 years (T3) after the war. Findings revealed that although PTSD was more prevalent and intense among veterans, the relative distribution of PTSD trajectories was similar among veterans and spouses. In both groups, the most prevalent was the resilient trajectory (43% and 73%, respectively), followed by the recovered trajectory (28% and 15%, respectively), the chronic trajectory (21% and 7%, respectively), and the delayed trajectory (8% and 6%, respectively). In addition, the composition of PTSD symptoms was similar among veterans and spouses at T1 and T2, but not at T3. These findings demonstrate that although PTSD is more prevalent and intense among individuals who were exposed to traumatic events directly as compared to those who were traumatized secondarily, the similarities in the clinical picture support the inclusion of secondary traumatization in PTSD Criterion A.

Individual and experiential predictors of character development across the deployment cycle

How soldiers adapt to and change in response to the deployment experience has received a great deal of attention. What predicts which soldiers are resilient and which soldiers decline in character strengths across the deployment transition? We examined this question in two analyses drawing from the same data source of soldiers deploying for the first time (Analysis 1: N = 179,026; Analysis 2: N = 85,285; Mage = 24.6–24.7 years old, SD = 4.87; 66.5–66.9% White). Specifically, we examined how individual (e.g. sociodemographic, military) and deployment (e.g. stressful experiences) characteristics predict character development across the deployment cycle. Character strengths were assessed once before and up to three times after soldiers’ return from deployment. Reproducing previous work, we found evidence for two classes of change—a resilient class (“stable high”) and a recovery class (“persistent low”). The strongest predictor of high, resilient character strength levels was better self-rated health at baseline. The findings are discussed in the context of the mechanisms that drive character development, evidence for post-traumatic growth, and practical implications for the U.S. Army.

Trajectories of suicidal ideation after first-episode psychosis: a growth mixture modeling approach

OBJECTIVE

The period immediately after the onset of first-episode psychosis (FEP) may present with high risk for suicidal ideation (SI) and attempts, although this risk may differ among patients. Thus, we aimed to identify trajectories of SI in a 2-years follow-up FEP cohort and to assess baseline predictors and clinical/functional evolution for each trajectory of SI.

METHODS

We included 334 FEP participants with data on SI. Growth mixture modeling was used to identify trajectories of SI. Putative sociodemographic, clinical, and cognitive predictors of the distinct trajectories were examined using multinomial logistic regression.

RESULTS

We identified three distinct trajectories: Non-SI trajectory (85.53% sample), Improving SI trajectory (9.58%), and Worsening SI trajectory (6.89%). Multinomial logistic regression model revealed that greater baseline pessimistic thoughts, anhedonia, and worse perceived family environment were associated with higher baseline SI followed by an Improving trajectory. Older age, longer duration of untreated psychosis, and reduced sleep predicted Worsening SI trajectory. Regarding clinical/functional evolution, individuals within the Improving SI trajectory displayed moderate depression at baseline which ameliorated during the study period, while the Worsening SI subgroup exhibited persistent mild depressive symptoms and greater functional impairment at follow-up assessments.

CONCLUSION

Our findings delineated three distinct trajectories of SI among participants with FEP, one experiencing no SI, another in which SI might depend on acute depressive symptomatology, and a last subset where SI might be associated with mild but persistent clinical and functional impairments. These data provide insights for the early identification and tailored treatment of suicide in this at-risk population.

Posttraumatic Stress Disorder Symptom Trajectories in ICU Family Caregivers

To use latent class growth analysis to identify posttraumatic stress disorder symptom trajectories in ICU family caregivers.

DESIGN

Prospective cohort study.

SETTING

The medical ICU at a tertiary-care center in the United States.

PARTICIPANTS

Adult patients experiencing acute cardiorespiratory failure (defined as requiring at least one of the following: 1) vasopressors, 2) noninvasive positive pressure ventilation, 3) high-flow nasal cannula, or 4) mechanical ventilation) were enrolled in a pair with their primary family caregivers.

MEASUREMENTS AND MAIN RESULTS

Participants were enrolled within the first 48 hours of ICU admission. Family caregiver posttraumatic stress disorder symptoms were measured using the Impact of Events Scale-Revised at four time points: at enrollment, shortly after ICU discharge, and at 3 and 6 months after ICU discharge. The data were examined using latent class growth analysis to identify posttraumatic stress disorder symptom trajectories. Two distinct symptom trajectories were identified: a persistently high trajectory, characterized by high posttraumatic stress disorder symptoms at initial assessment, which remained elevated over time, and a persistently low trajectory, characterized by low posttraumatic stress disorder symptoms at initial assessment, which remained low over time. Approximately two-thirds of caregivers belonged to the persistently high trajectory, and one-third of caregivers belonged to the persistently low trajectory.

CONCLUSIONS

Using latent class growth analysis to measure 6-month ICU family caregiver posttraumatic stress disorder symptom trajectories, we identified two distinct trajectories (persistently low and persistently high). A larger cohort study is warranted to further delineate posttraumatic stress disorder trajectories in this population, with the ultimate goal of targeting high-risk caregivers for interventions to reduce psychologic distress and improve long-term caregiver outcomes.

Exploring Risk and Resilient Profiles for Functional Impairment and Baseline Predictors in a 2-Year Follow-Up First-Episode Psychosis Cohort Using Latent Class Growth Analysis

Being able to predict functional outcomes after First-Episode Psychosis (FEP) is a major goal in psychiatry. Thus, we aimed to identify trajectories of psychosocial functioning in a FEP cohort followed-up for 2 years in order to find premorbid/baseline predictors for each trajectory. Additionally, we explored diagnosis distribution within the different trajectories. A total of 261 adults with FEP were included. Latent class growth analysis identified four distinct trajectories: Mild impairment-Improving trajectory (Mi-I) (38.31% of the sample), Moderate impairment-Stable trajectory (Mo-S) (18.39%), Severe impairment-Improving trajectory (Se-I) (12.26%), and Severe impairment-Stable trajectory (Se-S) (31.03%). Participants in the Mi-I trajectory were more likely to have higher parental socioeconomic status, less severe baseline depressive and negative symptoms, and better premorbid adjustment than individuals in the Se-S trajectory. Participants in the Se-I trajectory were more likely to have better baseline verbal learning and memory and better premorbid adjustment than those in the Se-S trajectory. Lower baseline positive symptoms predicted a Mo-S trajectory vs. Se-S trajectory. Diagnoses of Bipolar disorder and Other psychoses were more prevalent among individuals falling into Mi-I trajectory. Our findings suggest four distinct trajectories of psychosocial functioning after FEP. We also identified social, clinical, and cognitive factors associated with more resilient trajectories, thus providing insights for early interventions targeting psychosocial functioning.

Long-term development of post-traumatic stress symptoms and associated risk factors in military service members deployed to Afghanistan: Results from the PRISMO 10-year follow-up

Background

Symptoms of post-traumatic stress disorder (PTSD) can manifest several years after trauma exposure, and may impact everyday life even longer. Military deployment can put soldiers at increased risk for developing PTSD symptoms. Longitudinal evaluations of PTSD symptoms in deployed military personnel are essential for mapping the long-term psychological burden of recent operations on our service members, and may improve current practice in veterans’ mental health care.

Methods

The current study examined PTSD symptoms and associated risk factors in a cohort of Dutch Afghanistan veterans 10 years after homecoming. Participants (N = 963) were assessed seven times from predeployment up to 10 years after deployment. Growth mixture modeling was used to identify distinct trajectories of PTSD symptom development.

Results

The probable PTSD prevalence at 10 years after deployment was 8%. Previously identified risk factors like younger age, lower rank, more deployment stressors, and less social support were still relevant 10 years after deployment. Four trajectories of PTSD symptom development were identified: resilient (85%), improved (6%), severely elevated-recovering (2%), and delayed onset (7%). Only the delayed onset group reported increasing symptom levels between 5 and 10 years postdeployment, even though 77% reported seeking help.

Conclusions

This study provides insights into the long-term burden of deployment on the psychological health of military service members. It identifies a group of veterans with further increasing PTSD symptoms that does not seem to improve from currently available mental health support, and underlines the urgent need for developing and implementing alternative treatment opportunities for this group.

Deployment experiences and mental health problems as predictors of post-deployment unemployment length: a prospective, register-based study among Danish soldiers

OBJECTIVES

To test responses of formerly deployed soldiers (FDS) to a questionnaire on deployment experiences in combination with screening levels of post-traumatic stress disorder (PTSD) and depression approximately 6 months after homecoming as predictors of the subsequent probability of gaining employment when unemployed within 5 years post-deployment.

DESIGN, SETTING AND PARTICIPANTS

Danish FDS responders (n=3935) and non-responders (n=3046) to a 6-month post-deployment screening questionnaire after returning from a first-ever deployment to Kosovo, Iraq or Afghanistan (2002 to 2012) were included in the study and followed in public registers from 6 months to 5 years post-deployment.

PRIMARY AND SECONDARY OUTCOME MEASURES

We tested Cox regression models including deployment experiences (1a), screening levels of PTSD and depressive symptoms (1b), and their combination (2) for FDS responders. For all FDS, a secondary model included a measure on whether they responded to the questionnaire (3).

RESULTS

Neither the deployment experiences (1a) of exposure to danger and combat (HR=1.00, 95% CI=0.97 to 1.03) and witnessing consequences of war (HR=1.01, 95% CI=0.96 to 1.06), or the screening levels (1b) of PTSD (HR=1.06, 95% CI=0.84 to 1.33) and depressive symptoms (HR=0.82, 95% CI=0.64 to 1.06) were significant predictors of transitioning from unemployment to employment. Similar results were found for the combined model (2). A tendency among non-respondents (3) to have a lower probability of transitioning from unemployment to employment was found (HR=0.90, 95% CI=0.81 to 1.00).

CONCLUSION

Deployment experiences, PTSD and depressive symptoms, as measured at 6-month screening questionnaire, did not predict differences in the probability of gaining employment when unemployed within 5 years post-deployment. However, the findings suggest that those with the least probability of transitioning from unemployment to employment can be found among the non-responders to the post-deployment screening questionnaire.

Trajectories of depression symptoms from pre- to post- deployment: Does previous trauma predict symptom increase?

BACKGROUND

A significant minority of individuals experience depression following military deployment. The course of depression symptoms varies over time and across individuals; several factors including combat exposure influence depressions incidence and course. Importantly, previous trauma, especially in childhood, have been found increase the risk of post-deployment depression.

METHODS

In a prospective sample of 530 soldiers deployed to Afghanistan in 2009, we used latent growth mixture modeling (LGMM) to estimate trajectories of depression symptoms from before through 6.5 years after deployment. In a multinomial logistic regression model, we tested if childhood and adult life trauma predicted trajectory membership in combination with combat exposure and neuroticism.

RESULTS

We identified a large trajectory of few depression symptoms from before through 6.5 years after deployment (Low-stable, 86.5%), a trajectory with somewhat elevated symptoms (Medium-fluctuating, 4.0%), and a trajectory with few symptoms before deployment and a steep increase to a severe symptom level 6.5 years after deployment (Low-increasing, 9.4%). The Low-increasing trajectory was predicted by lower rank and childhood trauma, while the Medium-fluctuating trajectory was predicted by neuroticism, adult life trauma, and post-deployment PTSD symptoms.

LIMITATIONS

Attrition and use of self-report measures for depression and trauma.

CONCLUSIONS

Depression symptoms follow a heterogeneous course from before through 6.5 years after deployment with 9.4% experiencing symptom increase, resulting in severe symptoms 6.5 years after deployment. Trajectories are differentially predicted by rank, childhood and adult life trauma as well as neuroticism and PTSD symptoms, illustrating the clinical importance of taking individual differences of symptom course into account.

Additional Insights into the Relationship Between Brain Network Architecture and Susceptibility and Resilience to the Psychiatric Sequelae of Childhood Maltreatment

Childhood maltreatment is associated with increased risk for psychiatric and substance use disorders. However, some maltreated individuals appear resilient to these consequences while manifesting the same array of brain changes as maltreated individuals with psychopathology. Hence, a critical issue has been to identify compensatory brain alterations in these resilient individuals. We recently reported that maltreatment is associated with a more vulnerable structural brain network architecture. Resilient individuals have this same vulnerability but appeared to be able to effectively compensate due to reduced nodal efficiency (ability of a node to influence the global network) in 9 specific brain regions that moderate the relationship between maltreatment and psychopathology. Following up we now report that network vulnerability increases progressively during late adolescence to plateau at about 21 years of age, which may help to explain age of onset of psychopathology. Further, we found that network vulnerability was most significantly affected by parental verbal abuse between 16-18 years of age and number of types of maltreatment during childhood. Asymptomatic individuals with no history of psychopathology had more prominent alterations in nodal efficiency than asymptomatic individuals with prior history, who specifically showed reduced nodal efficiency in right amygdala and right subcallosal gyrus. Experiencing inadequate financial sufficiency during childhood increased risk of susceptibility versus resilience by 2.98-fold (95% CI 1.49-5.97, p = 0.002) after adjusting for differences in exposure to maltreatment. Interestingly, adequate-to-higher financial sufficiency appeared to be protective and was associated with reduced nodal efficiency in the right postcentral gyrus and subcallosal gyrus 'resilience' nodes.

Mental Health and Suicidality in Separating U.S. Reserve and National Guard Personnel

OBJECTIVE

We examined the association of U.S. Reserve Component (RC) personnel separating from military service with the risk of mental health problems at three time periods.

METHODS

Structured interviews were conducted with a nationally representative sample of 1,582 RC personnel at baseline and three follow-up waves from 2010 to 2013. Multivariate logistic regression analyses examined posttraumatic stress disorder (PTSD), major depressive disorder (MDD), binge drinking, suicide ideation, and mental health diagnosis by a health provider.

RESULTS

Approximately 10%, 20%, and 28% of RC personnel reported separating from military service at waves 2-4. At an estimated 6 months since leaving military service, there were no differences between those who left and those who remained in service. However, at 1 year after leaving service, those who had left had a higher risk of MDD, suicidal ideation, and reporting having mental health diagnosis by a health provider. At 1.6 years after leaving military service, those who had left had a higher risk of reporting having mental health diagnosis by a health provider. The results were essentially unchanged after adjusting for baseline mental disorder for each outcome.

CONCLUSION

Results suggest a higher risk of mental health problems in RC veterans separating, compared to those who remained in the military. This risk may not occur immediately following separation but may occur within the first year or two after separation. Transition from military to civilian life may be a critical period for interventions to address the unique needs of the RC's citizen-soldiers and reduce their risk of adverse mental health outcomes.

From the Frontline to the Homefront: The Experience of Israeli Veterans

In 1948, the state of Israel was created as a homeland for the Jewish people after 2,000 years of persecution and deportations in the diaspora. During the past 72 years, its inhabitants have experienced several wars and numerous terrorist attacks. Therefore, the issue of trauma goes beyond academic study, it is part of daily life. These circumstances have, unfortunately, turned Israel into a natural stress laboratory, which has enabled the systematic research of the biopsychosocial effects of traumatic stress on soldiers and civilians. This article reviews the findings of a series of studies that examine (a) the short- and long-term mental health effects of war on combat veterans; (b) the effects of repeated exposure to war on veterans; (c) trajectories of PTSD; and, specifically, (d) reactivation and (e) delayed-onset PTSD. We present the findings of two decades of systematic trauma research, which have followed the ongoing psychopathological effect of war on veterans. In understanding the ripple effects of trauma, it can be seen that veterans do not leave the events of the war behind once they are home; rather, it is with them wherever they go. Consequently, the trauma has a ripple effect that may carry over to veterans' spouses and offspring. The multiple manifestations and trajectories of both acute and chronic trauma will be presented. Clinical ramifications and implications will also be discussed.

Posttraumatic stress symptom courses in U.S. military veterans: A seven-year, nationally representative, prospective cohort study

The current study examined the nature and correlates of seven-year posttraumatic stress disorder (PTSD) symptom courses in a nationally representative, prospective cohort of U.S. military veterans. Data were analyzed from 2,307 trauma-exposed veterans who completed at least one follow-up assessment over a 7-year period, a subsample of n = 3,157 veterans who participated in the first wave of the National Health and Resilience in Veterans Study. Latent growth mixture modeling (LGMM) was used to identify PTSD symptom courses over four survey waves conducted in 2011, 2013, 2015, and 2018. Sociodemographic, health, and psychosocial variables were examined as potential correlates of symptomatic trajectories. PTSD symptoms were best characterized by three courses: No/Low (89.2%), Moderate Symptom (7.6%), and High Symptom (3.2%). Relative to the No/Low Symptom course, symptomatic courses were positively associated with a greater number of lifetime traumatic events, higher scores on measures of physical health difficulties and lifetime psychiatric history (relative risk ratio [RRR] range = 1.19-2.74), and were negatively associated with time since index trauma, household income, and social connectedness (RRR range = 0.14-0.97). Veterans in the Moderate Symptom course additionally had lower scores on a measure of protective psychosocial characteristics (RRR = 0.78) and were more likely to have received mental health treatment (RRR = 1.62), while those in the High PTSD Symptom course were more likely to be exposed to combat and to more traumas since Wave 1 (RRR range = 1.23-4.63). Three PTSD symptom courses in U.S. veterans were identified, with more than 10% of veterans exhibiting a moderate or high symptom course. Prevention and treatment efforts targeting modifiable correlates, such as social connectedness, may help mitigate symptomatic PTSD symptom courses in this population.

[Who stays healthy? The problem of predicting resilience]

BACKGROUND

Resilience is a complex construct commonly defined as a dynamic process of maintenance or rapid restoration of mental health during and following exposure to stress and trauma. Resilient individuals show no or only minimal disruption in their overall functioning following trauma. Predictors of individual resilience are currently unclear.

OBJECTIVE

Are there significant and reliable predictors of resilience?

MATERIAL AND METHODS

Analysis and summary of recent studies on psychosocial and neurobiological resilience predictors derived from longitudinal studies.

RESULTS

Less than half of the studies on psychosocial and neurobiological predictors reviewed indexed predictors for resilience prior to exposure to the traumatic event. The results are heterogeneous and often not replicated across studies. Even significant predictors often explain only a relatively small or clinically insignificant amount of variance in resilience.

CONCLUSION

The results are not yet ready for direct implementation into practice and the development of appropriate prevention programs on the basis of significant predictors.

Genetic and Environmental Predictors of Adolescent PTSD Symptom Trajectories Following a Natural Disaster

: Genes, environmental factors, and their interplay affect posttrauma symptoms. Although environmental predictors of the longitudinal course of posttraumatic stress disorder (PTSD) symptoms are documented, there remains a need to incorporate genetic risk into these models, especially in youth who are underrepresented in genetic studies. In an epidemiologic sample tornado-exposed adolescents (n = 707, 51% female, Mage = 14.54 years), trajectories of PTSD symptoms were examined at baseline and at 4-months and 12-months following baseline. This study aimed to determine if rare genetic variation in genes previously found in the sample to be related to PTSD diagnosis at baseline (MPHOSPH9, LGALS13, SLC2A2), environmental factors (disaster severity, social support), or their interplay were associated with symptom trajectories. A series of mixed effects models were conducted. Symptoms decreased over the three time points. Elevated tornado severity was associated with elevated baseline symptoms. Elevated recreational support was associated with lower baseline symptoms and attenuated improvement over time. Greater LGLAS13 variants attenuated symptom improvement over time. An interaction between MPHOSPH9 variants and tornado severity was associated with elevated baseline symptoms, but not change over time. Findings suggest the importance of rare genetic variation and environmental factors on the longitudinal course of PTSD symptoms following natural disaster trauma exposure.

Fourteen-year trajectories of posttraumatic stress disorder (PTSD) symptoms in UK military personnel, and associated risk factors

The aim of this study was to examine trajectories of posttraumatic stress disorder (PTSD) symptoms over a 14-year period and the risk factors associated with each trajectory. 1885 UK military personnel provided information at four time points since 2002. The PTSD Check list-Civilian Version (PCL-C) was used at all time points. Growth mixture models (GMM) were estimated to examine whether individuals could be clustered into discrete groups with similar trajectories. Multinomial logistic regressions were carried out to investigate factors associated with class membership. The three-class GMM was the most parsimonious solution. This included 90.2% in the resilient class, 4.1% in the improving class and 5.7% in the deteriorating class. Both the deteriorating and improving classes were associated with childhood adversity (odds ratios (OR) 3.9 (95% CI 2.3, 6.7) and 3.3 (95% CI 2.1, 5.0) respectively) and antisocial behaviour (OR 2.8 (95% CI 1.9, 4.2) and 3.7 (95% CI 2.4, 5.8) respectively), alcohol misuse (OR 3.5 (95% CI 2.4, 5.1) and 3.3 (95% CI 2.1, 5.2) respectively) and longer time since leaving Service in comparison to the resilient group. Those in the youngest group and those in a combat role (OR 0.32, 95% CI 0.19, 0.54) were more likely to belong to the deteriorating class. 10% of the cohort had symptoms of PTSD; of those, up to half were symptomatic for most of the follow-up period. Those whose score improved did not reach the low scores of the resilient group. Younger age and combat role were associated with worse prognosis of PTSD.

Role of social cognition in post-traumatic stress disorder: A review and meta-analysis

Social functioning is a key component of recovery after a potentially traumatic experience, and the buffering role of the social support in trauma resilience and recovery has been very well documented. Factors contributing to resilience and recovery are notable because although most people will experience a traumatic event during their lifetimes, only 6% to 10% are diagnosed with post-traumatic stress disorder (PTSD). The relationship between an individual and their social environment is determined both by the quality of the social environment itself, and by the individual's perception and understanding of information conveyed by the other people around them. However, little research has considered the contribution of these internal social cognitive processes to PTSD risk or resilience. The current review draws on the existing literature on social cognitive functioning in trauma exposure and PTSD, identifying key questions and themes for future research. We utilized a meta-analytic approach to assess the evidence for alterations in social cognition in PTSD, finding a consistent large deficit in social cognitive performance in PTSD groups relative to trauma-exposed and healthy controls. We then reviewed the literature on the interaction of genes and the social environment, supporting the hypothesis that social cognitive deficits are a preexisting risk factor for PTSD. Finally, we reviewed relevant neuroimaging findings, which suggest that alterations in social cognition affect the perception of threat cues in PTSD. Overall, research on social cognition and PTSD is still emerging, but existing findings suggest this is an important and understudied area for the understanding of PTSD.

Association of suicidal ideation with trajectories of deployment-related PTSD symptoms

This study examined the association between suicidal ideation and posttraumatic stress disorder (PTSD) symptom trajectories in a nationally representative sample of United States Reserve Component soldiers. PTSD symptoms related to a traumatic event during the most recent deployment were assessed in four annual waves in 2010-2013 among 682 Reserve Component soldiers. Latent Growth Mixture Modeling (LGMM) was used to examine the longitudinal trajectories of PTSD symptoms. The association between the PTSD trajectories and suicidal ideation at waves 2 to 4 was examined in logistic regression analyses. Four trajectories were identified: resilience (73.0%), recovery (11.7%), late onset (11.6%) and chronic (3.6%). Pairwise comparisons demonstrated significant differences between trajectories in risk of suicidal ideation. Among the chronic trajectory group, 50.9% reported suicidal ideation (25.8% late onset group; 11.3% recovery group; 4.0% resilience group). After controlling for baseline characteristics, the late onset and chronic trajectory groups were more likely to have suicidal ideation than the resilience and recovery trajectories, respectively. Findings suggest the late onset and chronic trajectories of PTSD symptoms are associated with higher risk of suicidal ideation. They support the importance of follow-up assessment of suicide risk even among individuals with low PTSD symptoms at homecoming.

Trajectories of resilience and dysfunction following potential trauma: A review and statistical evaluation

Given the rapid proliferation of trajectory-based approaches to study clinical consequences to stress and potentially traumatic events (PTEs), there is a need to evaluate emerging findings. This review examined convergence/divergences across 54 studies in the nature and prevalence of response trajectories, and determined potential sources of bias to improve future research. Of the 67 cases that emerged from the 54 studies, the most consistently observed trajectories following PTEs were resilience (observed in: n = 63 cases), recovery (n = 49), chronic (n = 47), and delayed onset (n = 22). The resilience trajectory was the modal response across studies (average of 65.7% across populations, 95% CI [0.616, 0.698]), followed in prevalence by recovery (20.8% [0.162, 0.258]), chronicity (10.6%, [0.086, 0.127]), and delayed onset (8.9% [0.053, 0.133]). Sources of heterogeneity in estimates primarily resulted from substantive population differences rather than bias, which was observed when prospective data is lacking. Overall, prototypical trajectories have been identified across independent studies in relatively consistent proportions, with resilience being the modal response to adversity. Thus, trajectory models robustly identify clinically relevant patterns of response to potential trauma, and are important for studying determinants, consequences, and modifiers of course following potential trauma.

Stress-Generative Effects of Posttraumatic Stress Disorder: Transactional Associations Between Posttraumatic Stress Disorder and Stressful Life Events in a Longitudinal Sample

Longitudinal studies have demonstrated transactional associations between psychopathology and stressful life events (SLEs), such that psychopathology predicts the occurrence of new SLEs, and SLEs in turn predict increasing symptom severity. The association between posttraumatic stress disorder (PTSD), specifically, and stress generation remains unclear. This study used temporally sequenced data from 116 veterans (87.9% male) to examine whether PTSD symptoms predicted new onset SLEs, and if these SLEs were associated with subsequent PTSD severity. The SLEs were objectively rated, using a clinician-administered interview and consensus-rating approach, to assess the severity, frequency, and personal dependence (i.e., if the event was due to factors that were independent of or dependent on the individual) of new-onset SLEs. A series of mediation models were tested, and results provided evidence for moderated mediation whereby baseline PTSD severity robustly predicted personally dependent SLEs, B = 0.03, p = .006, and dependent SLEs predicted increases in follow-up PTSD symptom severity, B = -0.04, p = .003, among participants with relatively lower baseline PTSD severity. After we controlled for baseline PTSD severity, personality traits marked by low constraint (i.e., high impulsivity) were also associated with an increased number of dependent SLEs. Our results provide evidence for a stress-generative role of PTSD and highlight the importance of developing interventions aimed at reducing the occurrence of personally dependent stressors.

Bayesian PTSD-Trajectory Analysis with Informed Priors Based on a Systematic Literature Search and Expert Elicitation

There is a recent increase in interest of Bayesian analysis. However, little effort has been made thus far to directly incorporate background knowledge via the prior distribution into the analyses. This process might be especially useful in the context of latent growth mixture modeling when one or more of the latent groups are expected to be relatively small due to what we refer to as limited data. We argue that the use of Bayesian statistics has great advantages in limited data situations, but only if background knowledge can be incorporated into the analysis via prior distributions. We highlight these advantages through a data set including patients with burn injuries and analyze trajectories of posttraumatic stress symptoms using the Bayesian framework following the steps of the WAMBS-checklist. In the included example, we illustrate how to obtain background information using previous literature based on a systematic literature search and by using expert knowledge. Finally, we show how to translate this knowledge into prior distributions and we illustrate the importance of conducting a prior sensitivity analysis. Although our example is from the trauma field, the techniques we illustrate can be applied to any field.

Apolipoprotein E gene polymorphism, trauma burden, and posttraumatic stress symptoms in U.S. military veterans: Results from the National Health and Resilience in Veterans Study

BACKGROUND

Previous research examining the association between apolipoprotein E (APOE) gene polymorphism and risk for posttraumatic stress disorder (PTSD) has been inconsistent due to the use of small and select samples. This study examined the relation between APOE genotype and PTSD symptoms in two nationally representative samples of U.S. military veterans. The potential effect of cumulative trauma burden and social support in moderating this association was also evaluated.

METHODS

The main sample consisted of 1,386 trauma-exposed European American (EA) veterans (mean age: 62-63 years) who participated in the National Health and Resilience in Veterans Study (NHRVS) in 2011. The independent replication sample consisted of 509 trauma-exposed EA veterans from the 2013 NHRVS.

RESULTS

APOE ε4 allele carriers reported significantly greater severity of PTSD symptoms than noncarriers in the main, but not the replication, sample. In both samples, the interaction of APOE ε4 carrier status and cumulative trauma burden was associated with greater severity of PTSD symptoms (F range = 2.53-8.09, all P's < .01), particularly re-experiencing/intrusion symptoms (F range = 3.59-4.24, P's < .001). Greater social support was associated with lower severity of PTSD symptoms among APOE ε4 allele carriers with greater cumulative trauma burden (β range -.27 to -.60, P's < .05).

CONCLUSION

U.S. military veterans who are APOE ε4 allele carriers and exposed to a high number of traumas may be at increased risk for developing PTSD symptoms than ε4 noncarriers. Greater social support may moderate this association, thereby highlighting the potential importance of social support promoting interventions in mitigating the effect of ε4 × cumulative trauma burden on PTSD risk.

Exploring resilience models in a sample of combat-exposed military service members and veterans: a comparison and commentary

Background: The term resilience is applied in numerous ways in the mental health field, leading to different perspectives of what constitutes a resilient response and disparate findings regarding its prevalence following trauma. Objective: illustrate the impact of various definitions on our understanding and prevalence of resilience, we compared various resilience definitions (absence of PTSD, absence of current mental health diagnosis, absence of generalized psychological distress, and an alternative trauma load-resilience discrepancy model of the difference between actual and predicted distress given lifetime trauma exposure) within a combat-exposed military personnel and veteran sample. Method: In this combat-trauma exposed sample (N = 849), of which approximately half were treatment seeking, rates of resilience were determined across all models, the kappa statistic was used to determine the concordance and strength of association across models, and t-tests examined the models in relation to a self-reported resilience measure. Results: Prevalence rates were 43.7%, 30.7%, 87.4%, and 50.1% in each of the four models. Concordance analyses identified 25.7% (n = 218) considered resilient by all four models (kappa = .40, p < .001). Correlations between models and self-reported resilience were strong, but did not fully overlap. Conclusions:The discussion highlights theoretical considerations regarding the impact of various definitions and methodologies on resilience classifications, links current findings to a systems-based perspective, and ends with suggestions for future research approaches on resilience.

Leadership and post-traumatic stress disorder: are soldiers' perceptions of organizational justice during deployment protective?

Background: Soldiers' perception of leadership during military deployment has gained research attention as a potentially modifiable factor to buffer against the development of postdeployment post-traumatic stress disorder (PTSD). Within nonmilitary research, the organizational justice (OJ) framework, i.e. distributive justice, procedural justice (PJ) and interactional justice (IJ), has been found to relate to mental health outcomes. Aspects of OJ may, therefore, be protective against PTSD. Objectives: We examined the prospective relationship between aspects of OJ, namely the perceptions of PJ and IJ by subordinate soldiers without leadership obligations in relationship to immediate superiors and PTSD. Method: Participants were soldiers (n = 245) deployed to Helmand Province in Afghanistan in 2009. Logistic regression procedures were used. The primary analysis measured PTSD cases using the Structured Clinical Interview for DSM-IV-TR Axis-I Disorder (SCID) 2½ years after homecoming. PJ/IJ was measured during deployment with a 6-item composite measure ranging from 0 to 12. Supplementary primary analyses were performed with PJ/IJ measured before and immediately after deployment. A secondary PJ/IJ analysis also tested against four postdeployment measures with the Post-Traumatic Stress Disorder Checklist Civilian (PCL-C) dichotomized at screening symptom levels. Results: Higher levels of perceived PJ/IJ for soldiers without leadership obligations during deployment had a prospective relation (OR = 0.86, 95% CI = 0.75-0.98) with PTSD on the SCID 2½ years after homecoming after adjustment for factors including predeployment PTSD symptoms, trauma and combat exposure, and state affectivity. Similar results were found by measuring PJ/IJ before (OR = 0.83, 95% CI = 0.71-0.95) but not immediately after homecoming (OR = 0.97, 95% CI = 0.85-1.11). A relationship with PTSD symptoms at the screening level at the four measurements of PCL-C was found, but only when predeployment PTSD symptoms were not controlled for. Conclusions: These results suggest that PJ/IJ exercised by superiors in relation to military deployments may protect subordinate soldiers against the development of postdeployment PTSD.

Perceived danger during deployment: a Rasch validation of an instrument assessing perceived combat exposure and the witnessing of combat consequences in a war zone

The potential stressors associated with military deployment are related to an increased risk of adverse mental health outcomes. Perceived exposure to combat has been found to be proportional to the severity of post-deployment posttraumatic stress disorder (PTSD). However, other perceived adversities during deployment, such as witnessing danger, distress, and hardship in the war zone, have been less systematically studied, but might play an equally substantial role for post-deployment mental health. The development and validation of scales that assess these related constructs are needed to distinguish their contribution to post-deployment risk of PTSD. We evaluated the validity of 10 items measuring perceived danger distributed to all deployed personnel with the Danish Defense since 1998. We hypothesize two scales: Exposure to Danger and Combat (EDC) and Witnessing Consequences of War (WCW). Two military cohorts deployed to Afghanistan in 2009 (Cohort 1, N = 276) and 2013 (Cohort 2, N = 273) were included. Questionnaire data was collected six months after homecoming, including deployment experiences and post-deployment reactions. We tested the construct validity of the 10 items of perceived danger with Rasch models (RM), focusing specifically on presence of subscales, and differential item functioning (DIF) across cohorts. We confirmed the existence of two separate subscales, EDCS and WCWS, both with adequate reliability. None of the subscales fitted a pure RM, but adequate fit was found for graphical log-linear RMs with evidence of DIF for the ECDS. However, adjusting the score to account for DIF had practically no effect, suggesting that the total non-adjusted mean score can be used in future cohort comparisons. Perceived exposure to combat and danger and witnessing consequences of war are related, but essentially distinct, concepts, each providing unique information about deployment adversities. Future studies should evaluate their shared and unique contribution to the risk of post-deployment PTSD.

Pre-deployment dissociation and personality as risk factors for post-deployment post-traumatic stress disorder in Danish soldiers deployed to Afghanistan

Objective: This study investigated whether pre-deployment dissociation was associated with previously identified post-traumatic stress disorder (PTSD) symptom trajectories from before to 2.5 years after military deployment. Furthermore, it examined whether the tendency to dissociate, pre-deployment personality factors, conceptualized by the Big Five model, and previous trauma represented independent risk factors for post-deployment PTSD symptoms. Method: This prospective study included the entire team of 743 soldiers from the Danish Contingent of the International Security Assistance Force 7 deployed to Afghanistan in 2009. Data consisted of self-report measures and were collected six times: before deployment; during deployment; and 1-3 weeks, 2 months, 7 months and 2.5 years after homecoming. Results: The findings indicate significant associations between pre-deployment dissociation and six PTSD trajectories (p < 0.001, η² = 0.120). Based on mean differences in dissociation for the six trajectories, two main groups emerged: a group with high dissociation scores at pre-deployment, which had moderate PTSD symptom levels at pre-deployment and fluctuated over time; and a group with low dissociation scores at pre-deployment, which had low initial PTSD symptom levels and diverged over time. Our study also confirmed previous findings of a positive association between neuroticism and dissociation (r = 0.31, p < 0.001). This suggests that negative emotionality may be a vulnerability that enhances dissociative experiences, although a causal link cannot be concluded from the findings. Finally, pre-deployment dissociation, pre-deployment neuroticism and a history of traumatic events, as independent factors, were significant predictors of post-deployment PTSD (p < 0.001, R² = 0.158). Conclusions: The study emphasizes the multiplicity of factors involved in the development of PTSD, and group differences in dissociative symptoms support the heterogeneity in PTSD. Further, this study points to specific aspects of personality that may be targeted in a clinical setting and in pre-deployment assessments in the military.

Trajectories of traumatic stress symptoms during conflict: A latent class growth analysis

BACKGROUND

The ways in which traumatic stress symptoms unfold under situations of ongoing threat and trauma exposure are poorly understood. The current study aims to identify traumatic stress symptom trajectories during conflict, as well as potential risk factors.

METHODS

Experience sampling methods were used to study traumatic stress symptoms during the 2014 Israel-Gaza conflict in 100 Israeli civilians exposed to rocket fire. Summary reports of traumatic symptoms were made twice-daily for 30 days via mobile phone.

RESULTS

Latent class growth analysis revealed four distinct classes (low, reducing, moderate, and high) characterised by their trajectory of traumatic stress symptoms during the conflict. Female gender, not being in a relationship, and higher prior trauma exposure were identified as potential risk factors.

LIMITATIONS

Data were not collected in the early phase of the conflict, the sample was relatively small, and only traumatic stress symptoms were investigated as outcomes.

CONCLUSIONS

This study identified heterogeneous traumatic stress symptom trajectories among civilians during a conflict, with different subgroups showing distinct response patterns over time, associated with various risk factors. Investigating responses to ongoing trauma, and identifying predictors of different stress symptom trajectories has clinical implications for the targeted delivery of interventions. Further exploration of heterogeneous trajectories could potentially elucidate mechanisms that drive resilience and recovery, including in situations of ongoing exposure such as during conflict.

Resilience and Posttraumatic Stress Disorder Symptoms in National Guard Soldiers Deployed to Iraq: A Prospective Study of Latent Class Trajectories and Their Predictors

This study examined the prospective course of posttraumatic stress disorder (PTSD) symptoms in a cohort of National Guard soldiers (N = 522) deployed to combat operations in Iraq. Participants were assessed 4 times: 1 month before deployment, 2-3 months after returning from deployment, 1 year later, and 2 years postdeployment. Growth mixture modeling revealed 3 distinct trajectories: low-stable symptoms, resilient, 76.4%; new-onset symptoms, 14.2%; and chronic distress, 9.4%. Relative to the resilient class, membership in both the new-onset symptoms and chronic distress trajectory classes was predicted by negative emotionality/neuroticism, odds ratios (ORs) = 1.09, 95% CI [1.02, 1.17], and OR = 1.22, 95% CI [1.09,1.35], respectively; and combat exposure, OR = 1.07, 95% CI [1.02, 1.12], and OR = 1.12, 95% CI [1.02, 1.24], respectively. Membership in the new-onset trajectory class was predicted by predeployment military preparedness, OR = 0.95, 95% CI [0.91, 0.98], perceived threat during deployment, OR = 1.07, 95% CI [1.03, 1.10], and stressful life events following deployment, OR = 1.44, 95% CI [1.05, 1.96]. Prior deployment to Iraq or Afghanistan, OR = 3.85, 95% CI [1.72, 8.69], predeployment depression, OR = 1.27, 95% CI [1.20, 1.36], and predeployment concerns about a deployment's impact on civilian/family life, OR = 1.09, 95% CI [1.02, 1.16], distinguished the chronic distress group relative to the resilient group. Identifying predeployment vulnerability and postdeployment contextual factors provides insight for future efforts to bolster resilience, prevent, and treat posttraumatic symptoms.

Resiliency and quality of life trajectories after injury

BACKGROUND

Injury can greatly impact patients' long-term quality of life. Resilience refers to an individual's ability to positively adapt after facing stress or trauma. The objective of this study was to examine the relationship between preinjury resiliency scores and quality of life after injury.

METHODS

Two hundred twenty-five adults admitted with an Injury Severity Score greater than 10 but without neurologic injury were included. The 36-item Short Form was administered at the time of admission and repeated at 1 month, 2 months, 4 months, and 12 months after injury. The Connor-Davidson Resilience Scale was completed at admission and scores were categorized into high resiliency or not high resiliency. Group-based trajectory modeling was used to identify distinct recovery trajectories for physical component scores (PCS) and mental component scores (MCS) of the 36-item Short Form. Multinomial logistic regression was used to determine whether baseline resiliency scores were predictive of PCS and MCS recovery trajectories.

RESULTS

Age, race, sex, mechanism of injury, Charlson Comorbidity Index, Injury Severity Score, presence of hypotension on admission, and insurance status were not associated with high resiliency. Compared with those who made less than US $10,000 per year, those who made more than US $50,000 per year had higher odds of being in the high resilience group (odds ratio, 10.92; 95% confidence interval, 2.58-46.32). Three PCS and 5 MCS trajectories were identified. There was no relationship between resilience and PCS trajectory. However, patients with high resiliency scores were 85% less likely to belong to trajectory 1, the trajectory that had the lowest mental health scores over the course of the study. Follow-up for the study was 93.8% for month 1, 82.7% for month 2, 69.4% for month 4, and 63.6% for month 12.

CONCLUSION

Patient resiliency predicts quality of life after injury in regards to mental health with over 25% of patients suffering poor mental health outcome trajectories. Efforts to teach resiliency skills to injured patients could improve long-term mental health for injured patients. Trauma centers are well positioned to carry out such interventions.

LEVEL OF EVIDENCE

Prognostic/epidemiologic study, level III.

Prevalence of PTSD and other mental disorders in UK service personnel by time since end of deployment: a meta-analysis

BACKGROUND

US studies have shown an increase of posttraumatic stress disorder (PTSD) and depression, but not alcohol misuse related to time of assessment since returning from deployment. We assessed if similar trends occur in the UK Armed Forces.

METHODS

We selected UK studies based on our data base of King's Centre for Military Health Research publications from 2006 until January 2016 with at least one of the following measures: PTSD checklist-civilian version (PCL-C), the General Health Questionnaire (GHQ-12) and the Alcohol Use Disorders Identification Test (AUDIT). The studies included personnel assessed for these outcomes after their most recent deployment. A search in Medline, Psycho-Info and Embase confirmed that no relevant publication was missed.

RESULTS

Twenty one thousand, seven hundred and forty-six deployed personnel from nine studies contributed to the meta-analyses by time since end of deployment in the PTSD analysis. The number of studies for period of time varied from two to four studies. The trend by time-category of questionnaire completion since returning from deployment were for PTSD β = 0.0021 (95 % CI -0.00046 to 0.0049, p = 0.12), for psychological distress β = 0.0123 (95 % CI 0.005 to 0.019, p = 0.002) and for alcohol misuse β = 0.0013 (-0.0079 to 0.0105, p = 0.77).

CONCLUSIONS

There was no evidence that the prevalence of PTSD and alcohol misuse changed according to time since the end of deployment over a three-year period, but there was evidence for an association with increasing psychological distress.

Posttraumatic Stress Disorder in U.S. Military Primary Care: Trajectories and Predictors of One-Year Prognosis

We examined the longitudinal course of primary care patients in the active duty Army with posttraumatic stress disorder (PTSD) and identified prognostic indicators of PTSD severity. Data were drawn from a 6-site randomized trial of collaborative primary care for PTSD and dpression in the military. Subjects were 474 soldiers with PTSD (scores ≥ 50 on the PTSD Checklist -Civilian Version). Four assessments were completed at U.S. Army installations: baseline, and follow-ups at 3 months (92.8% response rate [RR]), 6 months (90.1% RR), and 12 months (87.1% RR). Combat exposure and 7 validated indicators of baseline clinical status (alcohol misuse, depression, pain, somatic symptoms, low mental health functioning, low physical health functioning, mild traumatic brain injury) were used to predict PTSD symptom severity on the Posttraumatic Diagnostic Scale (Cronbach's α = .87, .92, .95, .95, at assessments 1-4, respectively). Growth mixture modeling identified 2 PTSD symptom trajectories: subjects reporting persistent symptoms (Persisters, 81.9%, n = 388), and subjects reporting improved symptoms (Improvers 18.1%, n = 86). Logistic regression modeling examined baseline predictors of symptom trajectories, adjusting for demographics, installation, and treatment condition. Subjects who reported moderate combat exposure, adjusted odds ratio (OR) = 0.44, 95% CI [0.20, 0.98], or who reported high exposure, OR = 0.39, 95% CI [0.17, 0.87], were less likely to be Improvers. Other baseline clinical problems were not related to symptom trajectories. Findings suggested that most military primary care patients with PTSD experience persistent symptoms, highlighting the importance of improving the effectiveness of their care. Most indicators of clinical status offered little prognostic information beyond the brief assessment of combat exposure.

The influence of pre-deployment cognitive ability on post-traumatic stress disorder symptoms and trajectories: The Danish USPER follow-up study of Afghanistan veterans

OBJECTIVE

New trajectories of PTSD symptoms have recently been identified in war exposed army veterans. The aim of this army veterans study was to examine whether pre-deployment cognitive ability is associated with the risk of developing PTSD symptoms or non-resilient PTSD trajectories.

METHOD

Follow up study in 428 Danish soldiers, deployed to Afghanistan in 2009, who were assessed at six occasions from pre-deployment to three years post-deployment. Pre-deployment vulnerabilities, deployment and homecoming stressors were measured. Pre-deployment cognitive test scores on Børge Priens Prøve (based on logical, verbal, numerical and spatial reasoning) were converted to a mean of 100 and with a standard deviation of 15.

RESULTS

Higher pre-deployment cognitive ability scores were associated with lower risk of PTSD symptoms as assessed by the Posttraumatic Stress Disorder Checklist-Civilian Version (PCL-C) 2.5 years post-deployment (OR=0.97; 95% CI 0.95-1.00) after adjustment for educational length, baseline PCL-C score and perceived war-zone stress. Compared to a resilient trajectory, a non-resilient relieved-worsening trajectory (high baseline mental symptoms, being symptom free during deployment and a drastic increase in PTSD symptoms at the final assessments of PTSD symptoms) had significantly lower cognitive scores by a mean difference of 14.5 (95% CI 4.7-24.3). This trajectory (n=9) comprised 26.5% of soldiers with moderate-severe PTSD symptoms 2.5 years post-deployment.

CONCLUSION

We confirmed an inverse association between pre-deployment cognitive ability and risk of PTSD symptoms, and observed significantly lower mean pre-deployment cognitive scores in one non-resilient PTSD trajectory. If replicated, this might inform relevant prevention efforts for soldiers at pre-deployment.

Brain-derived neurotropic factor polymorphisms, traumatic stress, mild traumatic brain injury, and combat exposure contribute to postdeployment traumatic stress

BACKGROUND

In addition to experiencing traumatic events while deployed in a combat environment, there are other factors that contribute to the development of posttraumatic stress disorder (PTSD) in military service members. This study explored the contribution of genetics, childhood environment, prior trauma, psychological, cognitive, and deployment factors to the development of traumatic stress following deployment.

METHODS

Both pre- and postdeployment data on 231 of 458 soldiers were analyzed. Postdeployment assessments occurred within 30 days from returning stateside and included a battery of psychological health, medical history, and demographic questionnaires; neurocognitive tests; and blood serum for the D2 dopamine receptor (DRD2), apolipoprotein E (APOE), and brain-derived neurotropic factor (BDNF) genes.

RESULTS

Soldiers who screened positive for traumatic stress at postdeployment had significantly higher scores in depression (d = 1.91), anxiety (d = 1.61), poor sleep quality (d = 0.92), postconcussion symptoms (d = 2.21), alcohol use (d = 0.63), traumatic life events (d = 0.42), and combat exposure (d = 0.91). BDNF Val66 Met genotype was significantly associated with risk for sustaining a mild traumatic brain injury (mTBI) and screening positive for traumatic stress. Predeployment traumatic stress, greater combat exposure and sustaining an mTBI while deployed, and the BDNF Met/Met genotype accounted for 22% of the variance of postdeployment PTSD scores (R (2)  = 0.22, P < 0.001). However, predeployment traumatic stress, alone, accounted for 17% of the postdeployment PTSD scores.

CONCLUSION

These findings suggest predeployment traumatic stress, genetic, and environmental factors have unique contributions to the development of combat-related traumatic stress in military service members.

Post-traumatic stress symptoms 5 years after military deployment to Afghanistan: an observational cohort study

BACKGROUND

Deployment can put soldiers at risk of developing post-traumatic stress symptoms. Despite several longitudinal studies, little is known about the timing of an increase in post-traumatic stress symptoms relative to pre-deployment. Longitudinal studies starting pre-deployment, in which participants are repeatedly measured over time, are warranted to assess the timing of an increase in symptoms to ultimately assess the timing of an increase in treatment demand after deployment.

METHODS

In this large observational cohort study, Dutch military personnel who were deployed to Afghanistan as part of the International Security Assistance Forces between March, 2005, and September, 2008, were assessed for post-traumatic stress symptoms with the Self-Rating Inventory for Post-traumatic Stress Disorder (SRIP) questionnaire. Participants were assessed 1 month before deployment and followed up at 1 month, 6 months, 12 months, 2 years, and 5 years after deployment, with changes in SRIP scores compared with pre-deployment using a mixed model analysis. The primary outcome was the total score of post-traumatic stress symptoms measured with SRIP at pre-deployment and the five follow-up assessments, with a score of 38 used as the cutoff to indicate substantial post-traumatic stress symptoms.

FINDINGS

Between March, 2005, and September, 2008, 1007 participants were recruited to this study. The results show two important effects of deployment on post-traumatic stress symptoms. A short-term symptom increase within the first 6 months after deployment (symptom increase coefficient for SRIP score vs pre-deployment [β] 0·99, 95% CI 0·50-1·48); and a long-term symptom increase at 5 years after deployment (β 1·67, 1·14-2·20).

INTERPRETATION

This study underlines the importance of long-term monitoring of the psychological health of soldiers after deployment because early detection of symptoms is essential to early treatment, which is related to improved psychological health.

FUNDING

Dutch Ministry of Defense.

Early identification of posttraumatic stress following military deployment: Application of machine learning methods to a prospective study of Danish soldiers

BACKGROUND

Pre-deployment identification of soldiers at risk for long-term posttraumatic stress psychopathology after home coming is important to guide decisions about deployment. Early post-deployment identification can direct early interventions to those in need and thereby prevents the development of chronic psychopathology. Both hold significant public health benefits given large numbers of deployed soldiers, but has so far not been achieved. Here, we aim to assess the potential for pre- and early post-deployment prediction of resilience or posttraumatic stress development in soldiers by application of machine learning (ML) methods.

METHODS

ML feature selection and prediction algorithms were applied to a prospective cohort of 561 Danish soldiers deployed to Afghanistan in 2009 to identify unique risk indicators and forecast long-term posttraumatic stress responses.

RESULTS

Robust pre- and early postdeployment risk indicators were identified, and included individual PTSD symptoms as well as total level of PTSD symptoms, previous trauma and treatment, negative emotions, and thought suppression. The predictive performance of these risk indicators combined was assessed by cross-validation. Together, these indicators forecasted long term posttraumatic stress responses with high accuracy (pre-deployment: AUC = 0.84 (95% CI = 0.81-0.87), post-deployment: AUC = 0.88 (95% CI = 0.85-0.91)).

LIMITATIONS

This study utilized a previously collected data set and was therefore not designed to exhaust the potential of ML methods. Further, the study relied solely on self-reported measures.

CONCLUSIONS

Pre-deployment and early post-deployment identification of risk for long-term posttraumatic psychopathology are feasible and could greatly reduce the public health costs of war.