Abstract
Background:
Military sexual trauma (MST) and military combat trauma (MCT) are significant risk factors for posttraumatic stress disorder (PTSD). However, no studies have directly contrasted the clinical profiles of Veterans between military-related traumas. Moreover, a notable gender difference in the likelihood of trauma exposure limits our ability to disentangle gender and trauma type.
Materials and Methods:
To address these gaps, we aimed at (1) contrasting psychiatric complaints in Veterans with MST versus MCT exposure and (2) investigating gender differences in Veterans with MST histories. Treatment-seeking Veterans (N = 563) completed semi-structured diagnostic interviews and self-report assessments of PTSD, depressive, and dissociative symptoms.
Results:
Psychiatric complaints and morbidity were notable after all military-associated traumas, although those seeking care for MST-related events demonstrated more severe PTSD, depressive, and dissociative symptoms and were more likely to meet criteria for non-PTSD anxiety and psychotic disorders. In contrast, few gender-related differences were noted between male and female Veterans with histories of MST.
Conclusions:
The experience of MST may reduce typically observed gender-related buffering effects for certain conditions.
Introduction
W
Notably, military-associated traumas are particularly salient risk factors for the development of posttraumatic stress disorder (PTSD) and its related mental health problems. Epidemiological research suggests that male and female Veterans with military combat trauma (MCT) are four times more likely to develop PTSD than their peers who are not exposed to combat. 4 PTSD is similarly pronounced among Veterans with histories of MST, a trauma subtype that has received heightened attention in recent years. Available empirical data indicate five- to eightfold higher PTSD rates among female Veterans exposed to MST and three- to sixfold higher PTSD rates among male Veterans compared with Veterans not exposed to MST or the general population, respectively. 4,5
Despite emerging evidence that women Veterans and those who have experienced MST are at increased risk for PTSD, the clinical needs and presentations of these subgroups are vastly understudied. It cannot be assumed that empirical findings related to male Veterans seeking treatment for combat-related traumas will be generalized to their military peers. Attention to the interrelationships between MCT and MST exposure, gender, and psychological concomitants may offer unique insights to improve treatment planning, augment our ability to clinically address PTSD and accompanying complaints, and effectively serve the needs of understudied Veteran subpopulations (i.e., women, those with histories of MST).
Much of the existing literature contrasts Veterans' gender or trauma type to understand varying rates of psychological concomitants. However, it is important to extend beyond examining which groups appear to “suffer most” after trauma to attend to the clinical presentations commonly encountered, particularly cases of comorbidity. 6 Participant selection further hinders our understanding of military-associated traumas. Currently, studies have recruited through survey formats or incorporate all Veterans Healthcare Administration (VHA) patients.
This type of research may be suitable for understanding the larger population of traumatized Veterans. However, this methodology diminishes our ability to recognize and adequately respond to Veterans when they present for services to address their trauma history. For example, if it is the case that event-related disclosure stigma varies by gender and results in differentially diminishing the likelihood that some groups of Veterans will present for care after particular types of exposure, descriptive mental health studies based on the population as a whole may be less generalizable to clinical environments. For instance, it is possible that women Veterans are less likely to experience substance use problems than their male peers, but that they are more likely to elect to present for treatment when these problems are present. In contrast, it may be that they are more likely to delay seeking services until use problems are more pronounced. Evaluating the potential for differential clinical presentations for women and those with histories of MST may augment our ability to provide care for an increasingly diverse Veteran population.
Further, some evidence suggests that women may respond differently to traumatic experiences than their male peers, irrespective of trauma type. In systematic reviews of gender differences in civilian and Veteran populations, women are generally demonstrated to experience higher rates and severity of PTSD and particular comorbid psychiatric conditions. 5 –7 However, two studies described similar PTSD symptoms in male and female Operation Iraqi Freedom/Operation Enduring Freedom (OIF/OEF) Veterans despite gender differences in MST and MCT exposure rates, though their findings regarding depressive symptoms were inconsistent. 8,9
Several theories have been proposed to explain women's differential risk of particular mental health diagnoses. First, physiological divergences (i.e., chemical, genetic propensity for fear acquisition, etc.) and differential behavioral coping responses are pronounced and vary by gender. Although women may utilize fewer active coping skills, they are often more likely to self-disclose distress or seek mental healthcare. 10 –12 Female Veterans are more apt to report pre-military trauma exposure. These earlier traumas may exponentially increase their risk for adverse outcomes when they are faced with additional military stressors. 6 However, studies of military samples have not replicated this consistently. 5 For example, Hourani et al. 13 recently found that active duty women had higher overall PTSD symptoms and had stronger symptom responses in light of injury-related combat traumas, whereas men with histories of lifetime sexual trauma exceeded PTSD severity scores of women with similar histories. Continued evaluation of the relative importance of gender and trauma type appears especially warranted for service members.
Research that is focused on associations between trauma exposure and mental health consistently confirms the presence of various negative psychological outcomes, in addition to PTSD, after both MCT and MST. Veterans who meet criteria for PTSD secondary to combat often struggle with comorbid mental health concerns such as depression, non-PTSD anxiety disorders, dissociation, and substance use. 14 –16 Similarly, individuals reporting a history of MST are more likely to meet PTSD criteria and show higher rates of substance use, depression, suicidal ideation and behavior, and disordered eating behaviors compared with Veterans who do not report MST or civilian women with adult sexual trauma. 17 –21 However, the existing literature has limited ability to account for clinical differences that may be particularly relevant.
Specifically, the dearth of studies directly comparing Veterans with MCT and MST inhibits the recognition of characteristics that may impact mental health trajectories and treatment selection decisions post-trauma. To illustrate this, MST survivors must often continue to work and reside alongside their perpetrators, potentially prolonging stress exposure and inhibiting trauma recovery. 22 Military culture emphasizes collectivism, individual strength, and loyalty. After MST, many Veterans describe stigma, fear of consequences, and a loss of control and privacy. Superior officers may be responsible for the incident or advise survivors not to report incidents that may be seen as career threatening. MST survivors may be labeled as troublemakers and discharged from the military, often resulting in a sense of betrayal and a loss of social and economic resources. Combat experiences may involve increased exposure to physically graphic material involving injury or death. For many, deployment to warzones involves repeated trauma exposure that may extend for multiple tours, involve concomitant environmental stressors, and disrupt access to social support networks. 23 Further, from the perspective of the Emotional Processing Theory, 24 the meanings attached to traumatic experiences serve salient roles in the development and maintenance of PTSD and associated negative affective states (sadness, guilt, disgust, anxiety, anger). Given the military trauma that event types may differ in, in either the nature of the event itself or, potentially, disparate meaning elements, it is possible that survivors may experience their PTSD differently (i.e., differences in trauma-related cognitions, situations that evoke hyperarousal and intrusions, changes in interpersonal connections and behaviors). Further research of clinical correlates of these experiences is warranted.
Another limitation of the current empirical literature on military-associated traumas has been the use of gender-restricted participant selection. Regarding MCT-related PTSD, most studies have focused on male Veterans given their historically greater exposure to warzone traumas. Similarly, investigations of MST generally include women Veterans exclusively or contrast Veterans with MST with all other Veterans, irrespective of possible MCT exposure. Although less attention has been afforded to male survivors of MST, emerging evidence suggests that they may express heightened concerns of being publicly ostracized, shamed, or perceived as non-masculine. 25,26 Some evidence indicates the characteristics of sexual trauma differ by gender. For instance, male Veterans appear more likely than their female peers to describe MST that is repetitive, involves multiple assailants, and includes simultaneous physical battery. 5
To evaluate these issues, Kimerling et al. 2 researched mental health presentations among male and female Veterans with and without reported MST. They demonstrated that several disorders were more prevalent in those reporting MST, although the strength of these relationships varied by gender. Specifically, women Veterans with positive MST screens were significantly more likely to screen positive for PTSD, anxiety, and alcohol use disorders than their male counterparts endorsing MST. Although MST was associated with elevated rates of bipolar disorder, the odds ratio for this diagnosis within the context of MST was less pronounced for women. For other disorders, gender did not appear to pose unique risks for clinical symptoms after MST. Their results suggest that MST may moderate the association between gender and Veterans' mental health symptoms.
However, Kimerling et al.'s study contrasted those with and without MST histories, and the percentage of those with MCT experiences was not reported. This methodology renders it impossible to disentangle whether reported gender differences reflect responses to any trauma or whether these results are specific to MST and would not generalize to MCT. Further, the positive MST screening used to derive groups is not, necessarily, indicative that MST events would satisfy diagnostic criteria for PTSD.
To date, the disentangling of clinical presentations that are associated with gender and military trauma exposure type has been difficult. To address this gap, we aimed at describing the prevalence and severity of psychological complaints experienced by treatment-seeking Veterans. To achieve this goal, we contrasted clinical intake evaluation profiles separately for military-associated trauma (MCT vs. MST; Aim 1) and for men and women after MST (Aim 2).
Materials and Methods
Procedures
Veterans seeking treatment at a Midwestern VHA specialty PTSD clinic between 2005 and 2013 completed all measures as part of a standard intake. Veterans (N = 563) completed self-report questionnaires on demographics, trauma history, and PTSD, depression, and dissociative symptoms followed by a semi-structured clinical interview (Mini-International Neuropsychiatric Interview [MINI]) 27 to screen for PTSD and to assess for other clinical diagnoses. During the initial interview, Veterans provided a verbal account of their trauma history and indicated the “index event” that was currently causing the most distress. For the purposes of this study, analyses were restricted to Veterans with military sexual or combat index events satisfying Diagnostic and Statistical Manual of Mental Disorders-IV (DSM-IV-TR) 28 A1 criteria for the PTSD diagnosis. The hospital's Human Subjects Internal Review Board approved the research protocol. De-identified clinical data were examined.
Measures
Demographics
As part of the intake process, participants provided demographic information, including gender, education, age, race, marital status, and military service.
Psychiatric symptom severity
Posttraumatic Stress Disorder Checklist-Civilian version (PCL-C)
The PCL-C 29 is a 17-item self-report questionnaire of PTSD symptom severity based on DSM-IV-TR 28 (APA) diagnostic criteria. Items are scored from 1 (not at all) to 5 (extremely bothered) by the presence of the symptom during the past month, with total scores ranging from 17 to 85. The PCL-C has demonstrated adequate validity and reliability. 30
Patient Health Questionnaire-9
The Patient Health Questionnaire-9 (PHQ-9) 31 is a self-report measure of depressive symptoms based on DSM-IV criteria. Items are scored from 0 (not at all) to 3 (nearly every day), and total scores can range from 0 to 27. Scores above 9 are suggestive of moderate or greater depressive symptom severity, and scores above 13 are reflective of a current Major Depressive Episode. 32 The PHQ-9 has demonstrated very good internal reliability (Cronbach's alpha = 0.89) and excellent internal consistency reliability. 31
Dissociative Experiences Scale
The Dissociative Experiences Scale (DES) 33 is a self-report measure of dissociative symptoms. It consists of 28 items describing discrete dissociative experiences (e.g., “Some people have the experience of feeling that their body does not seem to belong to them”), each of which participants rate in terms of frequency of occurrence (0%–100% of the time). The scale is generally scored as a mean percentage across all items, with scores above 30% reflective of significant dissociative symptoms. 34 The DES has demonstrated good internal consistency reliability and excellent inter-rater reliability (kappa = 0.99). 35
Psychiatric morbidity
Mini-International Neuropsychiatric Interview
The MINI 27 is a brief, semi-structured clinical interview for the assessment of DSM-IV diagnoses. Because of the symptom overlap between PTSD and other comorbid disorders (i.e., anxiety, mood, medical conditions), positive responses to MINI items are further clarified and considered within the context of differential diagnoses to enhance specificity. This study reports the results from the psychiatric assessment of current major mood episodes (bipolar or major depression), non-PTSD anxiety disorders (obsessive compulsive, generalized anxiety, social phobia, panic, and agorophobia), alcohol and substance use disorders, and psychosis. The MINI has well-established psychometric properties. 27
Data analyses
Means, percentages, and standard deviations were reported for demographic information, as warranted. To evaluate the effect of trauma type (Aim 1), Veterans were grouped by the traumatic event associated with their current concerns (MST vs. MCT; n = 70 and 475, respectively). An additional sixteen individuals endorsed both MST and MCT traumas associated with distress. In these instances, the case was not included in the Aim 1 analyses (contrasting MST and MCT events). Between-group comparisons of symptom severity (PCL-C, PHQ-9, DES) were conducted with analysis of variance (ANOVA) tests, and effect sizes were interpreted by using partial eta squared (ηp 2). Between-group comparisons of DSM-IV diagnoses based on the MINI interview (alcohol and other substance use, non-PTSD anxiety disorders, mood disorders, and schizophrenia/psychotic disorders) were calculated with Pearson's chi-square (χ2), and Fisher's Exact tests and effect sizes were interpreted by using Cramer's V. Data were managed and analyzed with SPSS 22.0.
Regarding Aim 2 (gender differences), we were unable to evaluate the interaction between gender and both trauma types given the low number of women in the MCT group (n = 8). Rather, between-group analyses identical to those described earlier for Aim 1 were used to contrast mental health severity and morbidity differences between male (n = 46) and female (n = 40) Veterans reporting histories of MST (with or without combat).
Results
Participant characteristics
As anticipated with a Veteran sample, most participants were men (88%) and married (52%). The majority had at least a 12th grade level education (87%) and identified as White/non-Hispanic (84%). Regarding time of service, 46% served during the Vietnam era and 48% served during the Gulf War era (includes Operation Desert Storm through continued current service in Operation Iraqi Freedom, Operation Enduring Freedom, and Operation New Dawn). The mean age of our sample was 47 years (SD = 15.5), although this differed significantly between MST (mean = 47) and MCT (mean = 43) groups (F = 11.39, p < 0.001, ηp 2 = 0.02). The MCT group was also more likely to be male (χ2 = 250.47, p < 0.001, Cramer's V = 0.69). No other significant differences were observed between groups. See Table 1 for descriptive characteristics.
Gulf War, served during Gulf War era (which includes Operation Iraqi Freedom and Operation Enduring Freedom); MCT, military combat trauma; MST, military sexual trauma; VN, served during Vietnam era.
Between-group comparisons of Veterans with histories of MST and MCT
ANOVA analyses were computed to assess for trauma type differences in psychiatric symptom severity (Table 2). For both groups, the average PTSD and depressive symptom severity score exceeded standard cutoff thresholds, which was suggestive of PTSD and major depressive disorder (MDD). Results indicated that depression and dissociative symptoms were significantly more elevated in Veterans endorsing MST, though the magnitudes of the differences were small. In contrast, no significant difference was identified for PTSD symptom severity.
Fisher's exact test.
Bold values denote p < .05.
DES, Dissociative Experiences Scale; MINI, Mini-International Neuropsychiatric Interview; PCL-C, PTSD Checklist-Civilian; PHQ-9, Patient Health Questionnaire-9; PTSD, posttraumatic stress disorder.
In both groups, the most common psychiatric diagnosis was PTSD, followed by mood disorders (Table 2). Among Veterans with MST, a non-PTSD anxiety disorder was the third most likely diagnosis, in contrast with an alcohol use disorder among Veterans with combat trauma. The MINI interview identified differences in the prevalence of some diagnostic comorbidities between groups. Specifically, those reporting MST were more likely to meet criteria for a non-PTSD anxiety disorder and a psychotic disorder than Veterans with histories of MCT. However, the magnitudes of these differences were generally small, and psychosis was a low base-rate diagnosis in the sample.
Between-group comparisons of male and female Veterans endorsing MST
In contrast to the trauma-type comparisons, no significant differences were found between men and women with histories of MST on PCL-C, PHQ-9, or DES symptom severity (Table 3). Similar to the comparisons of trauma type, on average, male and female Veterans with histories of MST exceeded recommended cutoff scores, which was suggestive of PTSD and MDD. Male and female Veterans in the MST group also presented with similar comorbidity profiles. PTSD and depressive disorders were the most common followed by non-PTSD anxiety, alcohol use, and substance use disorders. The only significant difference in the prevalence of psychiatric diagnoses was an elevated risk for psychotic disorders for men endorsing MST. The magnitude of the effect was medium; however, the base rate for diagnosis was low.
Fisher's exact test.
Bold values denote p < .05.
Discussion
This study is one of the first to examine psychiatric symptom severity and diagnostic morbidity based on both gender and military-related trauma type in treatment-seeking Veterans. Our descriptive study supports previous research indicating high levels of comorbidity in the context of PTSD for Veterans endorsing either MCT 14,15 or MST 17,19 and extends our knowledge to the clinical presentations that are the most commonly observed among women Veterans seeking treatment that is associated with military-related traumas.
Our findings have significant direct clinical applications. Although dissemination barriers persist, treatment outcome research has confirmed the benefits of trauma-focused interventions (i.e., Prolonged Exposure [PE] Therapy, Cognitive Processing Therapy) to reduce PTSD and depression in the context of MCT and MST. 36 –38 However, researchers investigating MST and MCT-related interventions may need to concurrently assess outcomes beyond PTSD and MDD to evaluate recovery from a broader array of concerns. Although MST and MCT were associated with similar PTSD severity, those with MST presented with greater symptoms of depression and dissociation and comorbid diagnoses of anxiety and thought disorders. Clinically, the significantly higher severity of dissociative symptoms within the context of MST may underscore a need for comparative studies to identify whether trauma-focused interventions are differentially effective in the context of PTSD with prominent dissociative complaints. However, we stress that the magnitude of observed differences between MCT and MST groups on continuous measures was small. Further research with larger samples of individuals presenting secondary to MST exposure may be beneficial to ascertain whether these differences are robust and clinically meaningful.
Of particular relevance, Schnurr et al. 39 contrasted PE therapy and presented centered therapy in a population of female Veterans seeking treatment primarily for sexual traumas. PE was associated with reductions in PTSD, depressive, and anxiety symptoms though improvements in comorbid symptoms were generally moderate in size and did not extend to alcohol or substance use complaints. Additional treatment outcome studies focusing on commonly described symptoms other than PTSD and depression continue to be warranted. Given the complexity of clinical presentations with MST, care providers must be especially skilled at integrating empirically based protocols with fidelity and flexibility and at attending to varying presentations (i.e., integration of PE and Exposure and Response Prevention for cases with comorbid PTSD and OCD, clinical management of dissociation).
Although previous investigations in civilian populations have suggested that women are at an increased risk for PTSD, irrespective of trauma type, 5 this was not found in our study. Rather, we observed no substantial differences between men and women with similar trauma histories. Our findings frame MST as a distinctively detrimental stressor. The between-gender similarity of PTSD symptoms severity after MST is consistent with some of the existing literature among combat-exposed OIF/OEF era Veterans. 3,13 Alternatively, another interpretation of our findings relates to a potential selection bias that is specific to assessment and treatment engagement. Specifically, if MST is associated with greater disclosure stigma, it may be the case that Veterans with this particular trauma type wait until they exceed a higher threshold of distress or symptom severity before they are willing to seek care. Together, these findings suggest that there may be unique characteristics of male and female service members (either before enrollment or within the context of the military) that prohibit the generalization of research findings on gender and trauma type to military samples.
In several instances, our conclusions are similar to those described by Kimerling et al. 2 In a notable exception within the MST literature, they examined gender differences in mental health conditions among Veterans with and without reported MST. Their findings indicated that PTSD, alcohol disorders, and anxiety disorders were closely associated with MST for both genders, though the relationship was stronger for women. In contrast, bipolar, psychotic, and adjustment disorders are also more prevalent among populations endorsing histories of MST, and they are more significantly associated with men. Importantly, dissociative, eating, and depressive disorders, conditions traditionally linked to female gender in general population studies, were found at similar rates for both genders with MST histories.
Similarly, when examining gender differences associated with MST, symptom severity, and clinical morbidities, we observed these to be markedly similar for male and female Veterans. This is noteworthy as several of the mental health complaints assessed have often been gender associated in other research samples (i.e., depressive, dissociative, and substance use complaints). 40,41 Several factors may explain this observation. First, it may be the case that previously identified gender differences observed in trauma samples are more reflective of the types of trauma reported, such as increased reporting of sexual trauma experiences by women. An alternative explanation is that, if gender differences in these domains do exist, the buffering effects typically conferred by gender noted in other samples are diminished in the context of MST.
Regarding the clinical utility of these findings, there is some evidence to suggest that women Veterans with comorbid PTSD and substance use problems are more frequently prescribed psychotropic medications that are inconsistent with VA Clinical Practice Guidelines. 42 Specifically, Bernardy et al. 43 reported that from 1999 to 2009, the rate for benzodiazepine prescription among VA utilizers diagnosed with PTSD was decreasing for men and increasing for women, even after controlling for other demographic characteristics and psychological comorbidities. Benzodiazepine utilization was higher for women with PTSD and substance use diagnoses, whereas the reverse was found for male Veterans. Irrespective of the etiology underlying the similar rates of substance use among male and female Veterans with histories of MST, clinical care providers are advised to thoroughly assess for substance use behaviors among women, be familiar with potential sex differences in pharmacokinetic responses and reproductive consequences of prescription use, and incorporate this critical information within care plans. Further research that avoids conflation of gender and trauma type is needed to clarify our findings and to confirm whether previous investigations related to gender differences in the context of PTSD generalize to those with histories of MST.
The present study also showed an increased risk for the diagnosis of thought disorders with male Veterans. This is consistent with research demonstrating increased risk for disorders such as schizophrenia in men, although this finding has been less well replicated in developed countries (see Aleman et al. 44 for a relevant meta-analytic review). We identified significant differences between gender and trauma type analyses, with occurrences of thought disorders predominantly observed among men endorsing MST. These results also mirror those observed by Kimerling et al. 2 in a sample of male and female VHA care utilizers with and without self-reported MST. However, we emphasize that this was a low base-rate condition, and our findings should be interpreted cautiously. Nonetheless, our results justify future research considerations, as the current lack of studies involving male survivors of MST may be obscuring an important clinical concern. If replicated, our results would suggest that longitudinal inquiry is needed to ascertain whether the risk of psychosis may be amplified by the experience of MST, whether prodromal or active symptoms of a thought disorder increase the likelihood of being sexually traumatized during the service, or whether other contextual factors may better explain this finding. Intervention research investigating treatment options for MST in the context of active or stabilized psychosis is similarly deficient. Further examination is warranted to replicate these preliminary findings and to establish the best practices for assessment and care.
Several limitations of this study are notable. First, we were unable to fully examine the main and moderating effects of gender and trauma type due to the small number of women with combat exposure in our clinical sample. Given the increasing rates of women engaging in and exposed to direct combat, continued attention of post-trauma trajectories of MCT among women is needed. 9,45 Although the percentages of male and female Veterans with MST and MCT parallel the anticipated rates expected in a VA population, the difference in gender proportionality that is particularly noteworthy within the MCT group limits our ability to more conclusively rule out gender-related effects. Further, to more clearly evaluate trauma-type differences, our research did not attend to dual MST and MCT exposure, which appears to be associated with particularly deleterious clinical outcomes. 46,47 It should also be recognized that Veterans might be hesitant to report certain types of trauma, such as MST, during clinical interviews. As such, it is possible that our MCT group may include several Veterans with both MCT and MST exposure. Moreover, our research aims were descriptive in nature and were not designed to identify biopsychosocial mechanisms that were responsible for observed differences.
Despite these disadvantages, our study yields several salient contributions to the literature. To our knowledge, this is the first investigation to directly examine clinical presentations based on both gender and trauma type in a single Veteran sample. Further, utilization of treatment-seeking participants, as in the present study, permits a better understanding of the clinical profiles that are likely to be encountered when Veterans present for mental healthcare, and it extends our knowledge on the clinical care needs of women Veterans and those exposed to MST. Awareness of similarities and divergences in clinical presentations may facilitate greater confidence in generalization of extant trauma research, when warranted, and concurrently assist in identifying areas in which differences may be clinically meaningful.
Footnotes
Acknowledgments
This article is the result of work supported with resources and the use of facilities at the VA Ann Arbor Healthcare System and the University of Michigan Department of Psychiatry. The contents do not represent the views of the U.S. Department of Veterans Affairs or the United States Government.
Author Disclosure Statement
No competing financial interests exist.
