Diagnostic performance of the PTSD checklist and the Vietnam Era Twin Registry PTSD scale.

AIMS: Self-report questionnaires are frequently used in clinical and epidemiologic studies to assess post-traumatic stress disorder (PTSD). A number of studies have evaluated these scales relative to clinician administered structured interviews; however, there has been no formal evaluation of their performance relative to non-clinician administered epidemiologic assessments such as the Composite International Diagnostic Interview (CIDI). We examined the diagnostic performance of two self-report PTSD scales, the PTSD checklist (PCL) and the Vietnam Era Twin Registry (VET-R) PTSD scale, compared to the CIDI. METHODS: Data were derived from a large epidemiologic follow-up study of PTSD in 5141 Vietnam Era Veterans. Measures included the PCL, VET-R PTSD scale and CIDI. For both the PCL and VET-R PTSD scale, ROC curves, areas under the curve (AUC), sensitivity, specificity, % correctly classified, likelihood ratios, predictive values and quality estimates were generated based on the CIDI PTSD diagnosis. RESULTS: For the PCL and VET-R PTSD scale the AUCs were 89.0 and 87.7%, respectively. Optimal PCL cutpoints varied from the 31-33 range (when considering sensitivity and specificity) to the 36-56 range (when considering quality estimates). Similar variations were found for the VET-R PTSD, ranging from 31 (when considering sensitivity and specificity) to the 37-42 range (when considering quality estimates). CONCLUSIONS: The PCL and VET-R PTSD scale performed similarly using a CIDI PTSD diagnosis as the criterion. There was a range of acceptable cutpoints, depending on the metric used, but most metrics suggested a lower PCL cutpoint than in previous studies in Veteran populations.

A new perspective on adiposity in a naturally obese mammal.

Many mammals seasonally reduce body fat due to inherent periods of fasting, which is associated with decreased leptin concentrations. However, no data exist on the correlation between fat mass (FM) and circulating leptin in marine mammals, which have evolved large fat stores as part of their adaptation to periods of prolonged fasting. Therefore, FM was estimated (by tritiated water dilution), and serum leptin and cortisol were measured in 40 northern elephant seal (Mirounga angustirostris) pups early (<1 wk postweaning) and late (6-8 wk postweaning) during their natural, postweaning fast. Body mass (BM) and FM were reduced late; however, percent FM (early: 43.9 +/- 0.5, late: 45.5 +/- 0.5%) and leptin [early: 2.9 +/- 0.1 ng/ml human equivalents (HE), late: 3.0 +/- 0.1 ng/ml HE] did not change. Cortisol increased between early (9.2 +/- 0.5 microg/dl) and late (16.3 +/- 0.9 microg/dl) periods and was significantly and negatively correlated with BM (r = 0.426; P < 0.0001) and FM (r = 0.328; P = 0.003). FM and percent FM were not correlated (P > 0.10) with leptin at either period. The present study suggests that these naturally obese mammals appear to possess a novel cascade for regulating body fat that includes cortisol. The lack of a correlation between leptin and FM may reflect the different functions of fat between terrestrial and marine mammals.

A comparison of subjective and physiological measures of mechanically produced and erotically produced erections (or, is an erection an erection?).

The current investigation explores possible reasons for the poor overall success rates of medical techniques used in the treatment of erectile dysfunction. This is the first study to compare directly the psychological impact of a mechanically produced versus an erotically produced erection. Subjective and objective parameters of sexual arousal were used to compare the experience of a mechanically attained erection versus an erotically stimulated erection. Twenty-eight (28) men without sexual dysfunction were asked to reach a full erection during each of the following two conditions: (a) by using an ErecAid System and (b) by self-stimulating while watching an erotic video. The results of this study suggest that the penile vacuum device was a successful method for attaining penile tumescence; however, the presence of penile tumescence was not accompanied by a subjective state of physical or mental sexual arousal. Thus, the mere physical presence of an erection does not seem to evoke bodily or mental feelings of sexual arousal. It is important to note that these findings suggest that attention to the psychosexual components of the individual's sexual experience are critical to the subjective experience of sexual arousal and reflect once again the multimodal response systems involved in sexual arousal. These results suggest that more effective treatment approaches would be based on a clinical strategy that provides instruction both on the technical use of a mechanical device as well as on the importance of creating an appropriate psychosexual environment.

Hispanic ethnicity and risk for combat-related posttraumatic stress disorder.

Hispanic veterans are said to exhibit higher risk of developing posttraumatic stress disorder (PTSD) than veterans of other racial/ethnic backgrounds. This prediction is based largely on findings from the National Vietnam Veterans Readjustment Study (NVVRS; R. A. Kulka et al., 1990a, 1990b). This article first summarizes the findings of the NVVRS with regard to race/ethnicity and PTSD, and then it makes a careful assessment of both the external and the internal validity of these findings. Conceptual issues are addressed and, where possible, further analyses of the NVVRS data set are conducted to identify factors that account for ethnic differences in rates of the disorder. Possible mediators of the effects of Hispanic ethnicity on vulnerability to PTSD are identified, including psychosocial factors (racial/ethnic discrimination and alienation) and sociocultural influences (stoicism and normalization of stress, alexithymia, and fatalism). Areas in which future research is needed are indicated.

Impact of combat and sexual harassment on the severity of posttraumatic stress disorder among men and women peacekeepers in Somalia.

The impact of combat and sexual harassment on the severity of posttraumatic stress disorder (PTSD) is compared for 1,307 men and 197 women peacekeepers who served in the same military units. A theoretical model was proposed to express the nature of the impact. Structural equation modeling was used to evaluate the model separately for men and women. Good-fitting, parsimonious models were developed that showed substantial similarity for men and women. For men, severity of PTSD symptoms was impacted by exposure to combat directly and indirectly through fear and sexual harassment. For women, severity of PTSD symptoms was impacted by combat indirectly through the same two influences, although the mechanisms involving fear and sexual harassment were somewhat different. For both genders, moreover, PTSD severity was impacted directly by exposure to the dying of the Somali people. These similarities suggest that in modern stressful overseas military missions, both genders may be susceptible to the same types of risk for the development of PTSD. The incidence and impact of sexual harassment is particularly noteworthy in the case of men and calls for more detailed investigation in future studies.

Emotional processing in posttraumatic stress disorder.

The emotional deficits associated with posttraumatic stress disorder (PTSD) are the least understood and the most understudied aspect of the syndrome. In this study, the connection was evaluated between trauma-context reactivity and subsequent emotional deficits in PTSD. Combat veterans with PTSD and well-adjusted veteran control participants were exposed to reminders of combat, after which their emotional behavior was assessed in response to a series of emotionally evocative images. Under the neutral condition, both groups exhibited emotional behavior modulated by stimulus valence. Partially consistent with the conceptual model described by B. Litz (1992), the PTSD group exhibited suppressed expressive-motor responses to positively valenced images, in comparison with the control group, only after being exposed to a trauma-related prime. Contrary to expectations, the PTSD group showed no augmentation of emotional response to negatively valenced cues after being exposed to trauma reminders. However, the PTSD group responded to all images, in both prime conditions, with higher heart rate reactivity, suggesting an automatic preparation for demand or threat in any uncertain emotional context. Possible causes and consequences of these results are discussed.

Predictors of emotional numbing, revisited: a replication and extension.

Litz et al. (1997), theorizing that emotional numbing (EN) is the result of emotional depletion caused by chronic hyperarousal, demonstrated that a cluster of hyperarousal symptoms was a robust predictor of EN symptoms. In the present study, these findings were replicated and extended in two multiple regression analyses of data from a large, multisite investigation (T. M. Keane et al., 1998) of psychophysiological responding by male combat veterans. The arousal (D) cluster of symptoms was again the most robust predictor of EN symptoms, whereas physiological indices of arousal and reactivity accounted for negligible amounts of variance in both regression equations. These findings underscore the possible link between disturbances related to arousal and the capacity of traumatized individuals to express and experience pleasant feelings.

Psychiatric symptomatology associated with contemporary peacekeeping: an examination of post-mission functioning among peacekeepers in Somalia.

Contemporary peacekeepers frequently confront complex stressors including the need to directly enforce peace between warring factions, to deliver humanitarian aid in the midst of political-social devastation, and to balance shifting rules of engagement. As such, it is proposed that participants may be at increased risk for the development of psychiatric distress. The present study examined the types of stressors encountered by 3,461 peacekeepers in Somalia, their current psychiatric functioning as measured by the Brief Symptom Inventory, and the relationship between exposure to various stressors and adjustment. Over one third of participants met criteria for psychiatric caseness. The most commonly reported symptoms included hostility, psychoticism, depression, and paranoid ideation. The best predictors of current functioning were found to be exposure to traditional war-zone-related stressors and general military pride and cohesion. These findings highlight the mental health consequences that service in a peacekeeping mission may have for United States solidiers. Further research is needed to investigate potential mechanisms that could serve as buffers to the stress associated with peacekeeping service.

Emotional response at the time of a potentially traumatizing event and PTSD symptomatology: a preliminary retrospective analysis of the DSM-IV Criterion A-2.

DSM-IV added an emotional response component to the definition of Criterion A for PTSD. The present study investigated the relationship between retrospective reports of emotional responses (fear, helplessness, and horror) and disrupted emotional responses ("numbing") at the time of a potentially traumatizing event and reports of PTSD symptomatology among undergraduate participants. We found that, of the DSM-IV criteria, only helplessness was significantly correlated with post-traumatic symptomatology. Reports of peritraumatic emotional numbing uniquely predicted subsequent PTSD symptomatology beyond coincident emotional responses, suggesting that further research is needed to explore the various dimensions of peritraumatic emotional response relevant to the development of PTSD.

Increases in retrospective accounts of war-zone exposure over time: the role of PTSD symptom severity.

Retrospective reports of the frequency of war-zone exposure are commonly used as objective indices in studies investigating the mental health consequences of exposure to such stressors. To explore the temporal stability of these types of reports, we obtained frequency estimates of exposure to war-zone stressors at two time points from 460 U.S. soldiers who had served in the peace-keeping mission in Somalia. On average; soldiers demonstrated a significant increase in their frequency reports from initial (postdeployment) to subsequent (follow-up) assessment. Severity of posttraumatic symptomatology was uniquely associated with this change, indicating a possible systematic bias in which severity of symptoms leads to increased reports of stressor frequency. The implications of these findings for research in the field of traumatic stress are discussed.

Lower precombat intelligence is a risk factor for posttraumatic stress disorder.

The authors examined the relation between intelligence and posttraumatic stress disorder (PTSD) by studying the association among precombat intelligence, current intelligence, and self-reported PTSD symptoms. Military aptitude test results were obtained in 59 PTSD and 31 non-PTSD Vietnam combat veterans who had undergone a psychodiagnostic interview and current intelligence testing. People with lower precombat intelligence were more likely to develop PTSD symptoms as assessed by the Clinician-Administered PTSD Scale even after adjustment for extent of combat exposure. The association between current intelligence and PTSD was no longer significant after adjusting for precombat intelligence. These results suggest that lower pretrauma intelligence increases risk for developing PTSD symptoms, not that PTSD lowers performance on intelligence tests.

The quality of the intimate relationships of male Vietnam veterans: problems associated with posttraumatic stress disorder.

This study examined the quality of the intimate relationships of male Vietnam veterans. Heterosexual couples in which the veteran had posttraumatic stress disorder (PTSD; n = 26) were compared to couples in which the veteran did not have PTSD (n = 24). Over 70% of the PTSD veterans and their partners reported clinically significant levels of relationship distress compared to only about 30% of the non-PTSD couples. Relationship difficulties appeared to encompass a wide range of areas, with PTSD veterans and their partners reporting that they had more problems in their relationships, more difficulties with intimacy, and had taken more steps toward separation and divorce than the non-PTSD veterans and their partners. The degree of relationship distress was correlated with the severity of veterans' PTSD symptoms, particularly symptoms of emotional numbing. Research and clinical implications of the results are discussed.

Predictors of emotional numbing in posttraumatic stress disorder.

Little is known about the mechanisms underlying emotional numbing (EN). The functional relationship between other classes of posttraumatic stress disorder (PTSD) symptoms and EN is also not well understood. In the present study, we examined the statistical predictors of EN. We hypothesized that the severity of EN would be most strongly associated with the hyperarousal symptoms rather than the avoidance symptoms of PTSD, or comorbid depression or substance abuse. This prediction was derived from psychological and biological models that posit EN to be a product of the depletion of emotional resources subsequent to chronic hyperarousal. Using hierarchical multiple regression in two separate samples of Vietnam combat veterans, we found hyperarousal symptoms to be the most robust predictor of EN. These data suggest that there is a substantive relationship between hyperarousal symptoms and EN in PTSD.

Posttraumatic stress disorder associated with peacekeeping duty in Somalia for U.S. military personnel.

OBJECTIVE: The end of the Cold War has marked a period when the U.S. military is asked to secure peace under conditions in which peace is tenuous, yet the need for resolution of the conflict is great. Combat-trained soldiers are highly visible and are exposed to threats to their lives, yet are asked to exhibit restraint and neutrality. The psychiatric consequences of peace-keeping duty under these conflicting and volatile conditions have been underresearched. The authors examined the prevalence of posttraumatic stress disorder (PTSD) associated with exposure to peacekeeping duty in Somalia. METHOD: A large cohort of active duty personnel deployed to Somalia (N = 3,461) were surveyed approximately 5 months after their return to the United States. A variety of military service characteristics and exposure variables and PTSD symptoms were examined. RESULTS: Eight percent of peacekeepers were found to meet diagnostic criteria for PTSD. PTSD symptom severity was best predicted by the rewards of military service, war zone stress, and frustrations with peacekeeping (e.g., restrictive rules of engagement). CONCLUSIONS: It is likely that the mission in Somalia represents a new paradigm of dangerous military operations for the United States. These data suggest that peacekeeping may be difficult to reconcile for some combat-trained soldiers and can create a risk for PTSD.

Warriors as peacekeepers: features of the Somalia experience and PTSD.

There has been scant empirical study of the psychological consequences of contemporary peacekeeping missions. This study examined relationships among 4 variables characterizing this type of operation (traditional combat events, negative aspects of peacekeeping, pressure to uphold restraint, and positive aspects of peacekeeping) and symptoms of posttraumatic stress disorder (PTSD). Participants were 3,310 male and female soldiers who served in the 1992-1994 Somalia mission. Structural equation modeling procedures were applied to data from subsamples of non-African Americans and African Americans. For both groups, traditional combat and negative aspects of peacekeeping were associated with PTSD, frustration with restraint, and positive aspects of peacekeeping; however, restraint was not related to PTSD. Discrepancies between the groups involved relationships among the restraint, positive aspects, and PTSD variables. Recommendations are offered to foster inquiry into this new research.

Attention, arousal, and memory in posttraumatic stress disorder.

Vietnam combat veterans with current posttraumatic stress disorder (PTSD), with other Axis-I disorders, or with no Axis-I disorders completed a series of tasks designed to elucidate the psychophysiological parameters of information-processing in PTSD. These tasks included a modified Stroop procedure (MSP), a standard Stroop procedure, a recognition memory task, and a threat rating task. Physiological responses were recorded throughout the study. Our data supported several predictions derived from information-processing models of PTSD. PTSD subjects exhibited greater MSP interference to high threat words than both comparison groups, and a liberal response bias toward recognizing military-related words. PTSD symptoms and threat reactions contributed to MSP interference effects for high-threat words after controlling for medications, depression, and baseline physiological activity.

Current and lifetime psychiatric disorders among veterans with war zone-related posttraumatic stress disorder.

Previous research has found high rates of psychiatric disorders among veterans with war zone-related posttraumatic stress disorder (PTSD). However, many studies in this area are methodologically limited in ways that preclude unambiguous interpretation of their results. The purpose of this study was to address some of these limitations to clarify the relationship between war zone-related PTSD and other disorders. Participants were 311 male Vietnam theater veterans assessed at the National Center for PTSD at the Boston Veterans Affairs Medical Center. The Clinician-Administered PTSD Scale and the Structured Clinical Interview for DSM-III-R were used to derive current and lifetime diagnoses of PTSD, other axis I disorders (mood, anxiety, substance use, psychotic, and somatoform disorders), and two axis II disorders (borderline and antisocial personality disorders only). Participants also completed several self-report measures of PTSD and general psychopathology. Relative to veterans without PTSD, veterans with PTSD had significantly higher rates of current major depression, bipolar disorder, panic disorder, and social phobia, as well as significantly higher rates of lifetime major depression, panic disorder, social phobia, and obsessive-compulsive disorder. In addition, veterans with PTSD scored significantly higher on all self-report measures of PTSD and general psychopathology. These results provide further evidence that PTSD is associated with high rates of additional psychiatric disorders, particularly mood disorders and other anxiety disorders. The implications of these findings and suggestions about the direction of future research in this area are discussed.