Jeffrey Knight

Deployment Risk and Resilience Inventory: A Collection of Measures for Studying Deployment-Related Experiences of Military Personnel and Veterans

This article describes the development of an inventory to assess key psychosocial risk and resilience factors for military personnel and veterans deployed to war zones or other hazardous environments. Part 1 details the definition and operationalization of the 14 constructs: 2 predeployment factors (e.g., childhood family environment), 10 deployment or war-zone factors (e.g., concerns about life and family disruptions, deployment social support, combat experiences), and 2 postdeployment factors (e.g., postdeployment stressors). In Parts 2 and 3, data from 2 separate national samples of Gulf War veterans were used to refine item sets and establish estimates of internal consistency reliability. Part 4 employed a 3rd new national sample of Gulf War veterans to document evidence for validity in terms of relations with mental and physical health.

Predictors of posttraumatic stress disorder and other psychological symptoms in trauma-exposed firefighters.

Firefighters are exposed to a range of potentially traumatic stressors, yet studies examining the impact of this exposure are equivocal. Although some studies suggest increased risk for mental health problems, others suggest unusual resilience. Type of assessment methodology may contribute to the lack of consistent findings. We assessed 142 trauma-exposed, professional firefighters utilizing a standardized clinical interview and self-report measures and found low rates of posttraumatic stress disorder (PTSD) diagnoses (4.2%), and depressive, anxiety, and alcohol-abuse symptoms. Frequency of trauma exposure did not predict psychological symptoms. Perceived social support, occupational stress, coping, as well as the interaction between perceived social support and self-blame were significant predictors of symptoms. Firefighters reporting low-perceived social support and high self-blame demonstrated the highest levels of clinically significant symptoms. These findings may inform education, treatment, and resilience training for emergency personnel.

Genome-wide association study to identify novel loci associated with therapy-related myeloid leukemia susceptibility

Therapy-related acute myeloid leukemia (t-AML) is a rare but fatal complication of cytotoxic therapy. Whereas sporadic cancer results from interactions between complex exposures and low-penetrance alleles, t-AML results from an acute exposure to a limited number of potent genotoxins. Consequently, we hypothesized that the effect sizes of variants associated with t-AML would be greater than in sporadic cancer, and, therefore, that these variants could be detected even in a modest-sized cohort. To test this, we undertook an association study in 80 cases and 150 controls using Affymetrix Mapping 10K arrays. Even at nominal significance thresholds, we found a significant excess of associations over chance; for example, although 6 associations were expected at P less than .001, we found 15 (P(enrich) = .002). To replicate our findings, we genotyped the 10 most significantly associated single nucleotide polymorphisms (SNPs) in an independent t-AML cohort (n = 70) and obtained evidence of association with t-AML for 3 SNPs in the subset of patients with loss of chromosomes 5 or 7 or both, acquired abnormalities associated with prior exposure to alkylator chemotherapy. Thus, we conclude that the effect of genetic factors contributing to cancer risk is potentiated and more readily discernable in t-AML compared with sporadic cancer.

Risk Factors for Mental, Physical, and Functional Health in Gulf War Veterans

Risk factors associated with war-zone events and circumstances are implicated in the health and adjustment of military veterans. We assessed a national stratified sample of community-residing veterans of the Gulf War (N = 357) using scales from the Deployment Risk and Resilience Inventory, along with an array of mental (posttraumatic stress disorder, depression, and anxiety), physical (symptom and condition indicators especially pertinent to Gulf War illnesses), and functional (both mental and physical dimensions) health outcomes. We found that perceived threat or fear of bodily harm in the war zone and self-reported or perceived exposures to environmental hazards may play a critical role in all measured aspects of health. Moreover, a synergistic effect of these two risk factors was observed in the prediction of mental health and mental health functional status.

Disaster mental health workers responding to ground zero: One year later

The current study examined anniversary reactions in mental health disaster relief workers following traumatic exposure at the site of the World Trade Center terrorist attacks. Despite relatively low levels of symptom reporting, workers endorsed an increase in both negative mood symptoms and functional impairment at the one-year anniversary of their traumatic exposure (compared to 6 months postexposure). For those individuals who met at least partial criteria for PTSD immediately following exposure, overall self-reported PTSD symptoms tended to increase from 6 to 12 months. This tendency resulted specifically from an increase in hyperarousal symptoms. Although few endorsed symptoms at clinical levels, our results demonstrate that disaster relief workers may experience an increase in symptomatology at the anniversary of their traumatic exposure.

Examining impelling and disinhibiting factors for intimate partner violence in veterans.

We examined correlates of intimate partner violence (IPV) in a military Veteran sample (N = 129) using Finkels (2007) framework for understanding the interactions between impelling and disinhibiting risk factors. Correlates investigated included head contact events (HCEs), posttraumatic stress disorder (PTSD) symptoms, and antisocial features. Results indicated that antisocial features were significantly associated with IPV at the bivariate level. PTSD symptoms also were associated with IPV, but this association was marginally significant. Tests of moderation provided support for the expectation that HCEs would potentiate associations between antisocial features and IPV. HCEs also moderated the association between PTSD symptoms and IPV. However, contrary to expectations, the opposite pattern emerged such that PTSD symptoms were associated with a higher rate of IPV for those without a history of HCEs. Study findings have potentially important implications for furthering our understanding of the complex etiology of IPV in this population.

The Use of the MMPI-2 Infrequency–Psychopathology Scale in the Assessment of Posttraumatic Stress Disorder in Male Veterans

This study evaluated the use of the FP (Infrequency–Psychopathology) scale of the Minnesota Multiphasic Personality Inventory—2 (MMPI-2) as a measure of symptom overreporting among 423 service-seeking male veterans with and without PTSD. Results were consistent with several predictions based on the logic of the FP scale. FP produced lower scores for PTSD and non-PTSD patients than the other two MMPI-2 measures of infrequent responding; F and FB. FP also resulted in fewer invalid protocols than did F or FB. Finally, FP yielded lower correlations with MMPI-2 and other measures of psychopathology than did F or FB. Consistent with previous studies, compensation-seeking status was associated with extreme elevations across clinical and validity scales. Contrary to previous findings, however, compensation-seeking veterans were also more likely to receive a PTSD diagnosis. Implications for the relationship between compensation seeking and symptom overreporting are discussed.

Differences in drinking patterns, occupational stress, and exposure to potentially traumatic events among firefighters: Predictors of smoking relapse

BACKGROUND AND OBJECTIVES Despite the increased awareness regarding the risks of cigarette smoking, this behavior continues to be a serious public health concern. As such, the goal of the current study was to examine risk factors for smoking relapse among individuals employed through fire service. METHODS In this report, drinking changes, trauma exposure, and occupational stress were compared among firefighters (N = 81) who reported a relapse to cigarette smoking (n = 27), a lifetime former history of smoking (n = 27), or no history of smoking (n = 27). Mechanisms behind tobacco relapse occurring after employment in fire service were explored. RESULTS Firefighters who relapsed to smoking, when compared to their nonsmoking peers, had higher rates of weekly alcohol consumption throughout their first year of fire service and had greater increases in drinking from preacademy to postacademy. CONCLUSIONS AND SCIENTIFIC SIGNIFICANCE Gaining a better understanding of these behaviors within this understudied and high-risk population may provide valuable information that can be used in designing future relapse prevention strategies as well as smoking cessation interventions.

Hypervigilance in college students: associations with betrayal and dissociation and psychometric properties in a brief hypervigilance scale

Betrayal trauma theory (Freyd, 1994, 1996) proposes that traumas high in social betrayal are expected to lead to psychological outcomes of dissociation, amnesia, and/or shame because these responses are adaptive to a survivor trying to preserve a necessary relationship in the face of mistreatment. Within the field of trauma studies more generally, there is substantial support for the proposition that traumas that cause intense fear should lead to posttraumatic anxiety and hypervigilance. Despite ample evidence for both theorized causal pathways, very few studies have tested associations between betrayal exposure, hypervigilance, and dissociation. The current study had 2 aims: first, as no self-report measure of hypervigilance had been developed for nonveteran populations, we sought to identify a subset of Hypervigilance Questionnaire (Knight, 1993) items that validly and reliably measure hypervigilance within college undergraduates (n = 489; 62.6% female, 69.9% Caucasian) with and without elevated levels of posttraumatic stress. Second, we tested the associations among trauma history, hypervigilance, and dissociation. Psychometric analyses revealed 5 hypervigilance items we introduce as the Brief Hypervigilance Scale. Partial correlations revealed that each posttraumatic response was not related to a history of low betrayal trauma (i.e. non-interpersonal trauma) controlling for betrayal trauma (i.e. interpersonal trauma), but was related to betrayal trauma controlling for low betrayal trauma. These associations remained significant after controlling for the other posttraumatic response (i.e. hypervigilance or dissociation). Follow-up analyses revealed that hypervigilance was independently associated with adult, but not child high betrayal trauma, and the opposite was true for dissociation. Implications for theory, research, and clinical practice are discussed.