To Örebro University

Posttraumatic stress disorder (PTSD) and sequelae of mild traumatic brain injury (mTBI) are presumed to contribute to reintegration difficulties in combat-exposed veterans. Yet their relative impacts on postdeployment functioning are not well understood. The current study used structural equation modeling (SEM) to clarify the extent to which symptoms of internalizing disorders (e.g., depression, anxiety), mTBI symptoms, and cognitive performance are associated with functional impairment in 295 combat-exposed veterans. SEM results showed that internalizing symptoms most significantly predicted functional impairment (r = 0.72). Blast mTBI and cognitive performance were associated with internalizing (r = 0.24 and -0.25, respectively), but functional impairment was only modestly related to cognition (r = -0.17) and unrelated to mTBI. These results indicate that internalizing symptoms are the strongest predictor of functioning in trauma-exposed veterans, exceeding the effects of mTBI and cognitive performance. This evidence supports prioritizing interventions that target internalizing psychopathology to improve functioning in cases of co-occurring PTSD and mTBI.

Objective: Spouse/partners of military personnel demonstrate elevated levels of distress during military deployments, yet there is insufficient information about courses of adjustment over time. The current study identified trajectories of depression and alcohol use problems and predictors of those trajectories across the deployment cycle.

Method: National Guard soldiers (N = 1973) and spouses/intimate partners (N = 1020) completed assessments of risk/protective factors and baseline measures of mental health functioning 2 to 5 months prior to soldiers' 1-year deployments (Time 1) to Kuwait/Iraq in support of Operation New Dawn or Afghanistan in support of Operation Enduring Freedom. Partners' mental health was reassessed at 4 months (Time 2) and 8 months (Time 3) after soldiers deployed, and both spouses/partners and soldiers were reassessed 2-3 months postdeployment (Time 4).

Results: Latent class growth modeling of partner depression symptoms over time revealed 4 groups: Resilience (79.9%), Deployment Distress (8.9%), Anticipatory Distress (8.4%), and Post-Deployment Distress (2.7%). Three alcohol misuse trajectories were identified: Resilience (91.3%), Deployment Onset (5.4%), and Deployment Desistance (3.3%). Predeployment predictors of partners' depression symptom trajectories varied by group and included soldier reports of stressors and social support and partner levels of neuroticism, introversion, disconstraint, and reported stressors. Predeployment predictors of alcohol misuse trajectories varied by group, and included soldier levels of alcohol misuse as well as partner neuroticism, disconstraint, and family readiness.

Conclusions: Delineating and predicting trajectories of partner adjustment can allow for better targeted interventions toward those most at risk for heightened distress or alcohol problems over the deployment cycle.

Using data from over 1,000 male and female twins participating in the Minnesota Twin Family Study, the authors examined developmental change, gender differences, and genetic and environmental contributions to the symptom levels of four externalizing disorders (adult antisocial behavior, alcohol dependence, nicotine dependence, and drug dependence) from ages 17 to 24. Both men and women increased in symptoms for each externalizing disorder, with men increasing at a greater rate than women, such that a modest gender gap at age 17 widened to a large one at age 24. Additionally, a mean-level gender difference on a latent Externalizing factor could account for the mean-level gender differences for the individual disorders. Biometric analyses revealed increasing genetic variation and heritability for men but a trend toward decreasing genetic variation and increasing environmental effects for women. Results illustrate the importance of gender and developmental context for symptom expression and the utility of structural models to integrate general trends and disorder-specific characteristics.

Background: Research suggests that personality traits have both direct and indirect effects on the development of psychological symptoms, with indirect effects mediated by stressful or traumatic events. This study models the direct influence of personality traits on residualized changes in internalizing and externalizing symptoms following a stressful and potentially traumatic deployment, as well as the indirect influence of personality on symptom levels mediated by combat exposure.

Method: We utilized structural equation modeling with a longitudinal prospective study of 522 US National Guard soldiers deployed to Iraq. Analyses were based on self-report measures of personality, combat exposure, and internalizing and externalizing symptoms.

Results: Both pre-deployment Disconstraint and externalizing symptoms predicted combat exposure, which in turn predicted internalizing and externalizing symptoms. There was a significant indirect effect for pre-deployment externalizing symptoms on post-deployment externalizing via combat exposure (p < 0.01). Negative Emotionality and pre-deployment internalizing symptoms directly predicted post-deployment internalizing symptoms, but both were unrelated to combat exposure. No direct effects of personality on residualized changes in externalizing symptoms were found.

Conclusions: Baseline symptom dimensions had significant direct and indirect effects on post-deployment symptoms. Controlling for both pre-exposure personality and symptoms, combat experiences remained positively related to both internalizing and externalizing symptoms. Implications for diagnostic classification are discussed.

The assumption of specific etiology in posttraumatic stress disorder (PTSD) differentiates the disorder from most other psychiatric conditions. A 'risky test' of the assumption of specific etiology and resultant trauma-related symptom dimensions was conducted through structural modeling of PTSD symptoms in soldiers before (N = 522) and after (n = 423) a combat deployment to Iraq. If PTSD represents a discrete diagnostic entity that emerges after trauma exposure, we hypothesized either the number of latent classes should increase from pre- to post-deployment or symptom dimensions should qualitatively distinguish affected from unaffected classes following trauma exposure. Comparison of latent structural models revealed best fitting hybrid models for PTSD and depression with strong invariance of symptom dimensions across classes both before and after deployment and only quantitative (i.e., severity) differences between classes. These findings suggest PTSD is generally well-conceptualized as a dimensional syndrome worsened but not necessarily elicited by trauma exposure.

Background: We hypothesized that gender differences in average levels on the internalizing and externalizing factors that account for co-morbidity among common psychopathological syndromes in both men and women account for gender differences in the prevalence of specific syndromes.

Method: The latent structure of 11 syndromes was examined in a middle-aged (mean age=52.66 years, S.D.=5.82) sample of 2992 (37% men) members of the community-based Minnesota Twin Registry (MTR) assessed using 10 scales of the Psychiatric Diagnostic Screening Questionnaire (PDSQ) and an adult antisocial behavior scale. Confirmatory factorial invariance models were applied to a best-fitting, internalizing-externalizing model.

Results: A 'strong gender invariance model' fit best, indicating that gender differences in the means of individual syndromes were well accounted for by gender differences in mean levels of internalizing and externalizing. Women exhibited higher mean levels of internalizing (d=0.23) and lower mean levels of externalizing (d=-0.52) than men.

Conclusions: These findings suggest that risk factors for common mental disorders exhibiting gender differences may influence prevalence at the latent factor level. Future research may benefit from focusing on both the latent factor and individual syndrome levels in explaining gender differences in psychopathology.

Background: Individual differences in fear and fearlessness have been investigated at their extremes in relation to markedly different forms of psychopathology - anxiety disorders and psychopathy, respectively. A documented neural substrate of fear-related traits and disorders is defensive reactivity as reflected in aversive startle potentiation (ASP).

Method: The current study extended prior work by characterizing, in a sample of adult twins from the community (n=2511), the phenotypic and etiologic structure of self-report measures of fear and fearlessness known to be associated with ASP.

Results: Analyses revealed a hierarchical structure to the trait fear domain, with an overarching, bipolar fear/fearlessness dimension saturating each measure in this domain, and subfactors labeled 'distress,' 'stimulation seeking' and 'sociability' accounting for additional variance in particular measures. The structure of genetic and non-shared environmental associations among the measures closely mirrored the phenotypic structure of the domain.

Conclusions: The findings have implications for proposals to reconceptualize psychopathology in neurobiological terms.

Antisocial behavior, substance use, and impulsive and aggressive personality traits often co-occur, forming a coherent spectrum of personality and psychopathology. In. the current research, the authors developed a novel quantitative model of this spectrum. Over 3 waves of iterative data collection, 1,787 adult participants selected to represent a range across the externalizing spectrum provided extensive data about specific externalizing behaviors. Statistical methods such as item response theory and semiparametric factor analysis were used to model these data. The model and assessment instrument that emerged from the research shows how externalizing phenomena are organized hierarchically and cover a wide range of individual differences. The authors discuss the utility of this model for framing research on the correlates and the etiology of externalizing phenomena.

BACKGROUND: Approximately 20% to 40% of trauma survivors experience posttraumatic stress disorder (PTSD). The American College of Surgeons Committee on Trauma reports that early screening and referral has the potential to improve outcomes and that further study of screening and intervention for PTSD would be beneficial. This prospective randomized study screened hospitalized patients for traumatic stress reactions and assessed the effect of a brief intervention in reducing later development of PTSD.

METHODS: The Primary Care PTSD (PC-PTSD) screen was administered to admitted patients. Patients with symptoms were randomized to an intervention or control group. The brief intervention focused on symptom education and normalization, coping strategies, and utilizing supports. The control group received a 3-minute educational brochure review. Both groups completed in-hospital interviews, then 45- and 90-day telephone interviews. Follow-up collected the PTSD checklist-civilian (PCL-C) assessment and qualitative data on treatment-seeking barriers.

RESULTS: The PC-PTSD screen was successful in predicting later PTSD symptoms at both 45 days ( = 0.43, p < 0.001) and 90 days ( = 0.37, p < 0.001) even after accounting for depression. Correlations of the intervention with the PCL-C scores and factor score estimates did not reach statistical significance at either time point (p = 0.827; p = 0.838), indicating that the brief intervention did not decrease PTSD symptoms over time. Of those at or above the PCL-C cutoff at follow-ups, a minority had sought treatment for their symptoms (43.2%). Primary barriers included focusing on their injury or ongoing rehabilitation, financial concerns, or location of residence.

CONCLUSION: The PC-PTSD screen identified patients who later assess positive for PTSD using the PCL-C. The brief intervention did not reduce 45- and 90-day PTSD development. Follow-up interviews revealed lack of treatment infrastructure in the community. It will be important for trauma centers to align with community resources to address the treatment needs of at-risk patients.

There is limited research testing longitudinal models of how posttraumatic stress disorder (PTSD) severity leads to impaired relationship adjustment. The present study evaluated 2 potential mechanisms among a longitudinal sample of National Guard soldiers deployed to the Iraq War: (1) sensitivity to cues associated with punishment within intimate relationships and (2) sensitivity to cues associated with incentives in intimate relationships. Participants were surveyed by mail 1 year after an extended 16-month combat deployment and again 2 years later. Using a cross-lagged panel analysis with 2 mediators (relationship-specific threat and incentive sensitivity), findings indicated Time 1 PTSD symptom severity significantly eroded relationship adjustment over time through greater sensitivity to cues of relationship-related punishment, but not through incentive sensitivity. Additionally, findings indicated sensitivity to cues of relationship-related threats maintains symptoms of PTSD while sensitivity to cues of relationship-related incentives maintains relationship adjustment. Finally, PTSD symptoms significantly predicted erosion of relationship adjustment over time; however, associations from relationship adjustment to changes in PTSD severity over time were nonsignificant. Findings are discussed within the context of reinforcement sensitivity theory and emotional processing theory of PTSD.

Although the negative effects of deployment on the health of military spouses have been studied, research on sleep disruptions remains limited. This study investigates trajectories of sleep complaints over the course of deployment and predictors of these changes among a cohort of at-home partners. Data were drawn from the Readiness and Resilience in National Guard Soldiers (RINGS-2) project, a prospective, longitudinal study of National Guard soldiers deployed to Iraq/Kuwait (2011-2012) and their intimate partners. Spouses or cohabiting partners (N = 686) of soldiers completed assessments of risk/protective factors 2 to 5 months before their partners' deployment (Time 1), 4 months (Time 2) and 8 months (Time 3) into the deployment, and 2 to 3 months following the soldiers' return (Time 4). Latent class growth analyses (LCGA) revealed quadratic change in partners' sleep over the deployment cycle, characterized by 4 distinct trajectories: resilient (61%), deployment-onset sleep problems (22%), deployment improvement (10%), and chronic (7%) groups. Predeployment and during deployment predictors of partners' sleep complaints varied by group and included negative emotionality, depression symptoms, alcohol use, low negative communication, and family stressors. Understanding the course of sleep complaints and potentially modifiable risk-factors among at-home partners during deployment may be useful for prevention and targeted intervention efforts.

Objectives: Concussions cause diverse symptoms that are often measured through a single symptom severity score. Researchers have postulated distinct dimensions of concussion symptoms, raising the possibility that total scores may not accurately represent their multidimensional nature. This study examined to what degree concussion symptoms, assessed by the Sport Concussion Assessment Tool 3 (SCAT3), reflect a unidimensional versus multidimensional construct to inform how the SCAT3 should be scored and advance efforts to identify distinct phenotypes of concussion.

Methods: Data were aggregated across two prospective studies of sport-related concussion, yielding 219 high school and college athletes in the acute (<48 hr) post-injury period. Item-level ratings on the SCAT3 checklist were analyzed through exploratory and confirmatory factor analyses. We specified higher-order and bifactor models and compared their fit, inter-pretability, and external correlates.

Results: The best-fitting model was a five-factor bifactor model that included a general factor on which all items loaded and four specific factors reflecting emotional symptoms, torpor, sensory sensitivities, and headache symptoms. The bifactor model demonstrated better discriminant validity than the counterpart higher-order model, in which the factors were highly correlated (r = .55-.91).

Conclusions: The SCAT3 contains items that appear unidimensional, suggesting that it is appropriate to quantify concussion symptoms with total scores. However, evidence of multidimensionality was revealed using bifactor modeling. Additional work is needed to clarify the nature of factors identified by this model, explicate their clinical and research utility, and determine to what degree the model applies to other stages of injury recovery and patient subgroups.

The Externalizing Spectrum Inventory (ESI; Krueger, Markon, Patrick, Benning, & Kramer, 2007) provides for integrated, hierarchical assessment of a broad range of problem behaviors and traits in the domain of deficient impulse control. The ESI assesses traits and problems in this domain through 23 lower order facet scales organized around 3 higher order dimensions, reflecting general disinhibition, callous aggression, and substance abuse. The full-form ESI contains 415 items, and a shorter form would be useful for questionnaire screening studies or multimethod research protocols. In the current work, we employed item response theory and structural modeling methods to create a 160-item brief form (ESI-BF) that provides for efficient measurement of the ESI's lower order facets and quantification of its higher order dimensions either as scale-based factors or as item-based composites. The ESI-BF is recommended for use in research on psychological or neurobiological correlates of problems such as risk-taking, delinquency, aggression, and substance abuse, and studies of general and specific mechanisms that give rise to problems of these kinds.

The Multidimensional Personality Questionnaire (MPQ) assesses a range of personality characteristics pertaining to affective and interpersonal style, behavioral restraint versus disinhibition, and capacity for sensory and imaginal engagement. Its 11 lower order trait scales map onto 3 higher order factors that reflect temperament dimensions. Its content and measurement properties have made the MPQ useful for elucidating constructs relevant to normal and abnormal behavior and investigating their neurobiological underpinnings. However, a barrier to its use in certain populations is the reading difficulty of some MPQ items. We describe efforts to develop a simplified-wording form, the MPQ-SF, composed of items readable at or below the seventh grade level (with most below sixth grade). Simplified-wording items demonstrated high convergence with original-wording items, and resulting trait scales showed adequate internal consistencies and appropriate higher order structure. The availability of a simplified version expands the potential utility of the MPQ to a wider range of samples.

A crucial challenge in efforts to link psychological disorders to neural systems, with the aim of developing biologically informed conceptions of such disorders, is the problem of method variance (Campbell & Fiske, 1959). Since even measures of the same construct in differing domains correlate only moderately, it is unsurprising that large sample studies of diagnostic biomarkers yield only modest associations. To address this challenge, a construct-network approach is proposed in which psychometric operationalizations of key neurobehavioral constructs serve as anchors for identifying neural indicators of psychopathology-relevant dispositions, and as vehicles for bridging between domains of clinical problems and neurophysiology. An empirical illustration is provided for the construct of inhibition disinhibition, which is of central relevance to problems entailing deficient impulse control. Findings demonstrate that: (1) a well-designed psychometric index of trait disinhibition effectively predicts externalizing problems of multiple types, (2) this psychometric measure of disinhibition shows reliable brain response correlates, and (3) psychometric and brain-response indicators can be combined to form a joint psychoneurometric factor that predicts effectively across clinical and physiological domains. As a methodology for bridging between clinical problems and neural systems, the construct-network approach provides a concrete means by which existing conceptions of psychological disorders can accommodate and be reshaped by neurobiological insights.

Families are a key source of support for National Guard Soldiers, yet little is known about the influence of parents on Soldiers’ pre-deployment well-being. In this chapter, we examine the potential role family may play in the psychological well-being of National Guard Soldiers. We present initial findings from the Readiness and Resilience in National Guard Soldiers (RINGS-2) study—an ongoing, prospective investigation of 2,089 National Guard Soldiers and their families. Single versus partnered Soldiers were compared on measures of pre-deployment well-being (post-traumatic stress symptoms, depression symptoms, and alcohol misuse). Prior to deployment, partnered Soldiers had higher PTSD and depression symptoms than single Soldiers, while single Soldiers reported greater alcohol misuse than partnered Soldiers. Multiple linear regression analyses examined the role of family contextual factors in understanding Soldiers’ pre-deployment well-being. Findings demonstrated the important role families can play in Soldiers’ well-being prior to deployment, both as a source of support and strain.

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.

Over the past decade, the USA has relied on unprecedented deployments of National Guard and Reserve Component service members to support sustained military operations in Afghanistan and Iraq. In this chapter, we review the empirical literature on the prevalence of PTSD among service members following deployment to Iraq and Afghanistan. Methodological issues to be considered when evaluating prevalence estimates across studies are reviewed, and the results of meta-analyses comparing PTSD prevalence rates for reserve and active components are critically examined. Finally, we summarize findings from the literature on risk and protective factors associated with PTSD that might account for the heightened risk of PTSD among Reservists during the post-deployment reintegration period.

Social support is a robust correlate of posttraumatic stress disorder (PTSD) symptoms and of general psychological distress (Ozer, Best, Lipsey, & Weiss, 2003). The nature of the causal relationship between support and PTSD remains the subject of debate, with 2 models, social erosion and social causation, often used to explain findings. Despite extensive research using these models, no studies of which we are aware have included tests of both models within the same series of analyses, across more than 2 time points, in veterans. These competing models were tested in a sample of National Guard soldiers (N = 521) who completed measures of perceived social support and the PTSD Checklist-Military version (Weathers, Litz, Herman, Huska, & Keane, 1993) at 3 months, 15 months, and 27 months following a combat deployment to Iraq. Analyses were run separately for overall PTSD symptoms and the PTSD components of intrusion, trauma-avoidance, dysphoria, and hyperarousal. Both the social erosion (s ranging from -.10 to -.19) and social causation (s ranging from -.08 to -.13) hypotheses were supported. Results suggested PTSD-specific symptom dimensions may both erode and be influenced by social support, whereas general psychological distress erodes social support. Implications for clinical intervention and research are discussed.

The development of the Externalizing Spectrum Inventory (ESI) was motivated by the need to comprehensively assess the interrelated nature of externalizing psychopathology and personality using an empirically driven framework. The ESI measures 23 theoretically distinct yet related unidimensional facets of externalizing, which are structured under 3 superordinate factors representing general externalizing, callous aggression, and substance abuse. One limitation of the ESI is its length at 415 items. To facilitate the use of the ESI in busy clinical and research settings, the current study sought to examine the efficiency and accuracy of a computerized adaptive version of the ESI. Data were collected over 3 waves and totaled 1,787 participants recruited from undergraduate psychology courses as well as male and female state prisons. A series of 6 algorithms with different termination rules were simulated to determine the efficiency and accuracy of each test under 3 different assumed distributions. Scores generated using an optimal adaptive algorithm evidenced high correlations (r > .9) with scores generated using the full ESI, brief ESI item-based factor scales, and the 23 facet scales. The adaptive algorithms for each facet administered a combined average of 115 items, a 72% decrease in comparison to the full ESI. Similarly, scores on the item-based factor scales of the ESI-brief form (57 items) were generated using on average of 17 items, a 70% decrease. The current study successfully demonstrates that an adaptive algorithm can generate similar scores for the ESI and the 3 item-based factor scales using a fraction of the total item pool.

Threat sensitivity (THT) and weak inhibitory control (or disinhibition; DIS) are trait constructs that relate to multiple types of psychopathology and can be assessed psychoneurometrically (i.e., using self-report and physiological indicators combined). However, to establish that psychoneurometric assessments of THT and DIS index biologically-based liabilities, it is important to clarify the etiologic bases of these variables and their associations with clinical problems. The current work addressed this important issue using data from a sample of identical and fraternal adult twins (N = 454). THT was quantified using a scale measure and three physiological indicators of emotional reactivity to visual aversive stimuli. DIS was operationalized using scores on two scale measures combined with two brain indicators from cognitive processing tasks. THT and DIS operationalized in these ways both showed appreciable heritability (0.45, 0.68), and genetic variance in these traits accounted for most of their phenotypic associations with fear, distress, and substance use disorder symptoms. Our findings suggest that, as indices of basic dispositional liabilities for multiple forms of psychopathology with direct links to neurophysiology, psychoneurometric assessments of THT and DIS represent novel and important targets for biologically-oriented research on psychopathology.

Background: Can core genetic liabilities for suicidal behavior be indexed using psychological and neural indicators combined? The current work addressed this question by examining phenotypic and genetic associations of two biobehavioral traits, threat sensitivity (THT) and disinhibition (DIS) - operationalized as psychoneurometric variables (i.e., composites of psychological-scale and neurophysiological measures) - with suicidal behaviors in a sample of adult twins.

Methods: Participants were 444 identical and fraternal twins recruited from an urban community. THT was assessed using a psychological-scale measure of fear/fearlessness combined with physiological indicators of reactivity to aversive pictures, and DIS was assessed using scale measures of disinhibitory tendencies combined with indicators of brain response from lab performance tasks. Suicidality was assessed using items from structured interview and questionnaire protocols.

Results: THT and DIS each contributed uniquely to prediction of suicidality when assessed psychoneurometrically (i.e., as composites of scale and neurophysiological indicators). In addition, these traits predicted suicidality interactively, with participants high on both reporting the greatest degree of suicidal behaviors. Biometric (twin-modeling) analyses revealed that a high percentage of the predictive association for each psychoneurometric trait (83% for THT, 68% for DIS) was attributable to genetic variance in common with suicidality.

Conclusions: Findings indicate that psychoneurometric assessments of biobehavioral traits index genetic liability for suicidal behavior, and as such, can serve as innovative targets for research on core biological processes contributing to severe psychopathology, including suicidal proclivities and actions.