Specificity of autonomic arousal to DSM-IV panic disorder and posttraumatic stress disorder

Although research on the hierarchical model of anxiety and depression has confirmed that autonomic arousability (AA) is more germane to panic disorder with or without agoraphobia (PD/A) than other DSM-IV anxiety and mood disorders, studies have not evaluated the differential relevance of AA to posttraumatic stress disorder (PTSD). This issue was addressed in multivariate analytic models using 295 outpatients with anxiety and mood disorders. Consistent with prediction, the presence of current DSM-IV PTSD and PD/A was significantly predictive of AA, even when other forms of anxiety disorder comorbidity were held constant. Moreover, latent structural analyses indicated that PTSD and PD/A were the only DSM-IV anxiety disorder constructs to have significant direct effects on AA (in accord with previous findings, the DSM-IV constructs of generalized anxiety disorder, social phobia, and obsessive-compulsive disorder did not have significant structural relationships with AA). The current findings, which attest to the specificity of AA to PTSD and PD/A, are discussed in context of other clinically salient shared features of these disorders and their relevance to treatment and diagnostic classification.     

Reliability of DSM-IV anxiety and mood disorders: implications for the classification of emotional disorders

The reliability of current and lifetime Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV; American Psychiatric Association, 1994) anxiety and mood disorders was examined in 362 outpatients who underwent 2 independent administrations of the Anxiety Disorders Interview Schedule for DSM-IV: Lifetime version (ADIS-IV-L). Good to excellent reliability was obtained for the majority of DSM-IV categories. For many disorders, a common source of unreliability was disagreements on whether constituent symptoms were sufficient in number, severity, or duration to meet. DSM-IV diagnostic criteria. These analyses also highlighted potential boundary problems for some disorders (e.g., generalized anxiety disorder and major depressive disorder). Analyses of ADIS-IV-L clinical ratings (0-8 scales) indicated favorable interrater agreement for the dimensional features of DSM-IV anxiety and mood disorders. The findings are discussed in regard to their implications for the classification of emotional disorders.     

Temporal patterns of anxious and depressed mood in generalized anxiety disorder: a daily diary study

Research suggests that anxiety disorders tend to temporally precede depressive disorders, a finding potentially relevant to understanding comorbidity. The current study used diary methods to determine whether daily anxious mood also temporally precedes daily depressed mood. 55 participants with generalized anxiety disorder (GAD) and history of depressive symptoms completed a 21-day daily diary tracking anxious and depressed mood. Daily anxious and depressed moods were concurrently associated. Daily anxious mood predicted later depressed mood at a variety of time lags, with significance peaking at a two-day lag. Depressed mood generally did not predict later anxious mood. Results suggest that the temporal antecedence of anxiety over depression extends to daily symptoms in GAD. Implications for the refinement of comorbidity models, including causal theories, are discussed.     

An examination of the construct validity of posttraumatic stress disorder with veterans using a revised criterion set

Ongoing concerns exist in the literature regarding the construct of posttraumatic stress disorder (PTSD) and how to best conceptualize and measure this disorder. We compared the traditional DSM-IV PTSD symptom criteria (i.e., symptoms from clusters B, C, and D) to a revised criterion set that omits overlapping mood and other anxiety symptoms on PTSD prevalence, PTSD diagnostic caseness, associated psychiatric comorbidity, functional status, and structural validity using a cross-sectional, multi-site primary care sample of 747 veterans. After removing items theorized to overlap with mood and other anxiety disorders, PTSD prevalence was identical using both criterion sets (i.e., 12%). Overall, there were few statistically significant differences in PTSD caseness, associated psychiatric comorbidity, functional status, and structural validity across the two diagnostic criterion sets. These data provide further support that removing items that overlap with other psychiatric disorders does not significantly impact the prevalence of PTSD, its associated comorbidity and functional impairment, or its structural validity. Although the revised criterion set represents a more parsimonious model, the current study findings generally support the strong construct validity of PTSD. The implications of these study findings for research and clinical practice are discussed.     

Examining a dimensional representation of depression and anxiety disorders' comorbidity in psychiatric outpatients with item response modeling

The current study replicated, in a sample of 2,300 outpatients seeking psychiatric treatment, a previous study (R. F. Krueger & M. S. Finger, 2001) that implemented an item response theory approach for modeling the comorbidity of common mood and anxiety disorders as indicators along the continuum of a shared latent factor (internalizing). The 5 disorders examined were major depressive disorder, social phobia, panic disorder/agoraphobia, specific phobia, and generalized anxiety disorder. The findings were consistent with the prior research. First, a confirmatory factor analysis yielded sufficient evidence for a nonspecific factor underlying the 5 diagnostic indicators. Second, a 2-parameter logistic item response model showed that the diagnoses were represented in the upper half of the internalizing continuum, and each was a strongly discriminating indicator of the factor. Third, the internalizing factor was significantly associated with 3 indexes of social burden: poorer social functioning, time missed from work, and lifetime hospitalizations. Rather than the categorical system of presumably discrete disorders presented in DSM-IV, these 5 mood and anxiety disorders may be alternatively viewed as higher end indicators of a common factor associated with social cost.     

The Underlying Role of Negative Affect in the Association between PTSD,Major Depressive Disorder,and Generalized Anxiety Disorder

Clinicians and researchers have found differential diagnosis to be difficult, particularly for conceptually similar disorders. One category of particular interest has been distress or internalizing disorders, theorized to be related via an underlying construct of generalized distress or negative affect. The present study attempted to address the comorbidity of three distress disorders - posttraumatic stress disorder (PTSD), major depressive disorder (MDD), and generalized anxiety disorder (GAD) - using latent analyses by controlling for the variance attributable to negative affect. The sample consisted of 265 trauma-exposed individuals who completed self-report measures of PTSD, MDD, GAD, and negative affect. Confirmatory factor analysis was used to test initial model fit. Next, the model was re-computed, controlling for negative affect by regressing negative affectivity at the item-level. Results indicated that a significant amount of variance within and between these diagnostic categories is attributable to negative affect at both the item- and factor-level. The hypothesis that MDD’s non-somatic/affective factor and the GAD factor would have the highest attenuations in factor loadings after controlling for negative affect was supported. Therefore, negative affect significantly influences the co-occurrence of PTSD, MDD, and GAD clinically, emphasizing the need for transdiagnostic interventions for trauma victims.     

Psychiatric Comorbidity in Children with Autism Spectrum Disorders: A Comparison with Children with ADHD

The present study was conducted with the aim to identify comorbid psychiatric disorders in children with autism spectrum disorders (ASD) (n = 40) and to compare those comorbidity rates to those in children with attention deficit hyperactivity disorder (ADHD) (n = 40). Participants were clinically referred children aged 7–18 years. DSM-IV classifications were used for the primary diagnosis (ASD/ADHD), while comorbid psychiatric disorders were assessed using a structured diagnostic interview, the structured clinical interview for DSM-IV, childhood diagnoses (KID-SCID). Twenty-three children with ASD (57.5 %) had at least one comorbid disorder, whereas 16 children with ADHD (40.0 %) were classified as having at least one comorbid disorder. No group differences were found with respect to this comorbidity rate or for the rate of comorbid externalizing disorders (ODD and/or CD). However, children with ASD had more comorbid internalizing disorders compared to children with ADHD. More specifically, children with ASD had higher rates of anxiety disorders, but not mood disorders. No associations between comorbidity and age or between comorbidity and the intelligence quotient was found. It is important for clinicians to always be aware of, and screen for, comorbidity, and to consider treatment for these comorbid disorders. In addition, research should focus on establishing valid and reliable screening tools as well as effective treatment options for these comorbid disorders.     

The structure of distress following trauma: posttraumatic stress disorder, major depressive disorder, and generalized anxiety disorder

The current report used confirmatory factor analysis to examine the latent structures of both key features and associated symptoms of three disorders that commonly develop following a traumatic event: posttraumatic stress disorder (PTSD), major depressive disorder (MDD), and generalized anxiety disorder (GAD). Participants were 228 motor-vehicle accident survivors who sought treatment for emotional difficulties. PTSD, MDD, and GAD were assessed with a combination of self-report and interview-based measures. The results of construct level analyses suggested that PTSD, MDD, and GAD are distinguishable but highly correlated disorders following a traumatic event. Symptom level analyses supported a model where the Reexperiencing, Avoidance, and Hypervigilance factors were subsumed under the PTSD construct. However, in this model the Dysphoria factor was a higher order construct correlated with the PTSD, MDD, and GAD factors, suggesting that the Dysphoria cluster may not be unique to PTSD. Diagnostic and theoretical implications of these results are discussed.     

Psychiatric correlates of childhood shyness in a nationally representative sample

Relations between adult anxiety and mood disorders and retrospective reports of excessive childhood shyness were investigated in the US National Comorbidity, Survey (n=5877). Results indicated that 26% of women and 19% of men described themselves as 'very shy' when they were growing up. Of these shy individuals, 53% of women and 40% of men met criteria for a lifetime diagnosis of one or more anxiety or mood disorders. Relations between excessive shyness and each of the anxiety and mood disorders were examined after adjusting for elevated neuroticism, self-criticism, and low maternal care. The largest odds ratios were found for social phobia in both men and women, particularly for the complex subtype of this disorder. Significant associations also emerged for posttraumatic stress disorder in women and for major depressive disorder in men. Childhood shyness remained significantly associated with a lifetime history of social phobia when individuals with current (past year) social phobia were excluded from the analysis. The results of this study suggest that childhood shyness is strongly related to the complex subtype of social phobia in the general population. Excessive shyness does not appear to be strongly associated with other anxiety and mood disorders when related psychosocial and developmental dimensions are statistically controlled. Finally, many individuals who report excessive childhood shyness do not meet criteria for any anxiety or mood disorder. In a similar fashion, approximately 50% of individuals with a lifetime history of complex social phobia did not view themselves as very shy when growing up.     

Comorbidity and Internet-Delivered Transdiagnostic Cognitive Behavioural Therapy for Anxiety Disorders

Internet-delivered transdiagnostic anxiety interventions aim to reduce symptoms across several anxiety disorders using one treatment protocol. However, it is unclear whether comorbidity affects outcomes of such treatment. This study re-examined data from a recent randomised controlled trial (N = 129) that evaluated the efficacy of an Internet-delivered transdiagnostic cognitive behavioural therapy (iCBT) intervention for participants with principal diagnoses of generalised anxiety disorder (GAD), social phobia (SP) panic disorder and agoraphobia (PDA), of whom 72% met criteria for a comorbid anxiety disorder or depression. Participants were divided into two groups based on whether or not they had a comorbid disorder before treatment. Participants with comorbid conditions reported higher symptom levels at pre-treatment, post-treatment, and follow-up across a range of measures. Both groups showed significant reductions in symptoms over treatment; however, participants with comorbid disorders showed greater reductions in measures of GAD, PDA, SP, depression, and neuroticism. In addition, treatment significantly reduced the number of comorbid diagnoses at follow-up. These results indicate transdiagnostic iCBT protocols have the potential to reduce comorbidity.     

Clarifying boundaries of binge eating disorder and psychiatric comorbidity: a latent structure analysis

Binge eating disorder (BED) presents with substantial psychiatric comorbidity. This latent structure analysis sought to delineate boundaries of BED given its comorbidity with affective and anxiety disorders. A population-based sample of 151 women with BED, 102 women with affective or anxiety disorders, and 259 women without psychiatric disorders was assessed with clinical interviews and self-report-questionnaires. Taxometric analyses were conducted using DSM-IV criteria of BED and of affective and anxiety disorders. The results showed a taxonic structure of BED and of affective and anxiety disorders. Both taxa co-occurred at an above-chance level, but also presented independently with twice-as-large probabilities. Within the BED taxon, diagnostic co-occurrence indicated greater general psychopathology, lower social adaptation, and greater premorbid exposure to parental mood and substance disorder, but not greater eating disorder psychopathology. Eating disorder psychopathology discriminated individuals in the BED taxon from individuals in the affective and anxiety disorders taxon. Diagnostic criteria of BED were more indicative of the BED taxon than were criteria of affective and anxiety disorders. The results show that at the latent level, BED was co-occurring with, yet distinct from, affective and anxiety disorders and was not characterized by an underlying affective or anxiety disorder.     

Comparison of treatment seeking compulsive buyers in Germany and the United States

OBJECTIVE: The aim of this pilot study was to compare a German (Bavaria) and an American (North Dakota) sample of women suffering from compulsive buying. METHOD: Thirty-eight German and 39 American female compulsive buyers were screened with the Compulsive Buying Scale (CBS), and the Yale-Brown Obsessive Compulsive Scale-Shopping Version (Y-BOCS-SV) prior to entering a group treatment study. Psychiatric co-morbidity was assessed with the Structured Clinical Interview for DSM-IV Axis I disorders (SCID). RESULTS: There were no statistically significant differences between the German sample and the American sample with regard to age (mean 43.7 and 45 years, respectively), and with regard to the scores on the CBS and the Y-BOCS-SV. A high lifetime co-morbidity rate with Axis I disorders, especially mood disorders, anxiety disorders, substance use disorders, OCD, and binge eating disorder was detected in both samples. Almost all participants met criteria for at least one lifetime Axis I disorder. However, German compulsive buyers showed significantly higher current prevalence rates of any affective disorder, and higher current and lifetime prevalence rates of any anxiety disorder and somatoform disorder. In addition, German compulsive buyers were significantly more likely to have more than one Axis I disorder. CONCLUSION: The groups did not differ with regard to age and with regard to the severity of compulsive buying and showed a high co-morbidity with Axis I disorders. However, the German compulsive buying sample presented with significantly more psychiatric co-morbidity compared to the American sample. Further research is needed to provide a better understanding of this disorder in general and cross-culturally.     

Diagnostic Comorbidity in Adults With Generalized Anxiety Disorder: Impact of Comorbidity on Psychotherapy Outcome and Impact of Psychotherapy on Comorbid Diagnoses

The current study examined the impact of comorbidity on cognitive and behavioral therapies for generalized anxiety disorder (GAD) as well as the impact of these therapies on diagnoses comorbid to GAD. Seventy-six treatment-seeking adults with principal diagnoses of GAD received 14 sessions of therapy. Most (n = 46; 60.5%) of the sample had at least one comorbid diagnosis. Although the presence of comorbid diagnoses was associated with greater severity of GAD symptoms at pretreatment, greater severity of comorbid major depression, simple phobia, and social phobia was associated with greater change in symptoms of GAD in response to treatment, with no effect on maintenance of gains during a 2-year follow-up. Further, psychotherapy for principal GAD led to a reduction in number of comorbid diagnoses and in severity of social phobia, simple phobia, and major depression at posttreatment. At 2-year follow-up severity of social and simple phobia remained below pretreatment levels, whereas severity of depression was no longer significantly below pretreatment levels. These results suggest that although people with comorbid disorders enter treatment with more severe GAD symptomatology, they demonstrate greater change, and therefore such comorbidity does not diminish the efficacy of cognitive and behavioral therapies for GAD. In addition, the impact of these treatments for GAD may generalize to reduced severity of simple phobia, social phobia, and major depression; however, gains in severity of major depression are not maintained.     

Syndrome comorbidity in patients diagnosed with a DSM-III-R anxiety disorder

One hundred thirty patients presenting at an anxiety disorders research clinic were administered a structured interview (i.e., Anxiety Disorders Interview Schedule-Revised). Diagnoses were made in accordance with Diagnostic and Statistical Manual (rev. 3rd ed.) criteria. Seventy percent of patients received at least one additional but secondary Axis I diagnosis. The most common additional diagnoses were simple and social phobia, which were assigned to nearly one third of all patients. In addition, 33% of anxiety disorder patients received an additional diagnosis of a depressive mood disorder (i.e., dysthymia or major depression). The distribution of specific additional diagnoses are presented for each principal anxiety disorder category. The scientific and clinical implications of comorbidity are discussed while considering the relatively high patterns of syndrome comorbidity found in the present study, which is consistent with several earlier studies.     

Examining Relationships Among Ethnicity,PTSD, Life Functioning,and Comorbidity in Female OEF/OIF Veterans

There is much literature on posttraumatic stress disorder (PTSD) and male combat veterans, but little on PTSD by gender and ethnicity among women combat veterans. We examine ethnic differences in PTSD and comorbid disorders among 37 Hispanic, 27 White, and 15 Native female Operaton Enduring Freedom/Operation Iraqi Freedom (OEF/OIF) combat veterans. Participants completed the Clinician-Administered PTSD Scale (CAPS), the Structured Clinical Interview for DSM-IV, Axis I (SCID-Axis I and II), Life Events Checklist (LEC), Military Stress Exposure Questionnaire (MSEQ), and the Medical Outcomes Study Short Form-36 (SF-36). Hispanics differed from Whites in having less education, more trauma exposure, higher levels of PTSD, mood disorder comorbidity, and poorer physical and emotional functioning. Natives differed from Whites with more trauma exposure, higher levels of PTSD, poorer emotional functioning, and higher rates of Cluster B PDs.     

Anxiety sensitivity within the anxiety disorders: disorder-specific sensitivities and depression comorbidity

The tendency to perceive anxious states as aversive and harmful is hypothesized to confer vulnerability to the development of anxiety disorders. The most commonly used measure of anxiety sensitivity, the Anxiety Sensitivity Index [ASI; Reiss, S., Peterson, R.A., Gursky, D.M., & McNally R.J. (1986). Anxiety sensitivity, anxiety frequency, and the prediction of fearfulness. Behavior Research and Therapy, 24, 1-8], is composed of multiple lower-order factors, assessing fear of physical symptoms, fear of publicly observable anxious symptoms, and fear of cognitive dyscontrol. This study examined the convergent validity of the lower-order anxiety sensitivity dimensions in DSM-IV diagnosed anxiety disorders. Participants with primary diagnoses of panic disorder with agoraphobia, social phobia, and generalized anxiety disorder (GAD) completed the ASI and measures of anxiety and depression severity. Support was found for the convergent validity of all ASI dimensions in reference to thematically related anxiety disorders and in the identification of patients presenting with and without secondary major depressive disorder (MDD). The ASI-fear of cognitive dyscontrol dimension displayed strong and nonredundant associations with GAD, dimensional depression scores, and secondary diagnoses of MDD. The conceptual implications of the shared importance of fear of cognitive dyscontrol in GAD and MDD are discussed.     

The developmental mental-disorder histories of adults with posttraumatic stress disorder: a prospective longitudinal birth cohort study

Clinical and epidemiologic studies have established that posttraumatic stress disorder (PTSD) is highly comorbid with other mental disorders. However, such studies have largely relied on adults' retrospective reports to ascertain comorbidity. The authors examined the developmental mental health histories of adults with PTSD using data on mental disorders assessed across the first 3 decades of life among members of the longitudinal Dunedin Multidisciplinary Health and Development Study; 100% of those diagnosed with past-year PTSD and 93.5% of those with lifetime PTSD at age 26 had met criteria for another mental disorder between ages 11 and 21. Most other mental disorders had first onsets by age 15. Of new cases of PTSD arising between ages 26 and 32, 96% had a prior mental disorder and 77% had been diagnosed by age 15. These data suggest PTSD almost always develops in the context of other mental disorders. Research on the etiology of PTSD may benefit from taking lifetime developmental patterns of comorbidity into consideration. Juvenile mental-disorder histories may help indicate which individuals are most likely to develop PTSD in populations at high risk of trauma exposure.     

Two studies of psychiatric morbidity among motor vehicle accident survivors 1 year after the crash

We assessed the psychiatric co-morbidity associated with chronic posttraumatic stress disorder (PTSD) (1-2 years) secondary to personal injury motor vehicle accidents (MVAs) in two studies. In Study 1, we compared the results of SCID assessments for 75 treatment-seeking MVA survivors (51 with PTSD and 24 with symptoms but no PTSD). In Study 2, we compared similar results among 132 MVA survivors who had been followed prospectively for 12+ months after their accidents (19 with PTSD, 32 who had PTSD but who had remitted, and 81 who never met criteria for PTSD). We found comparable levels of current co-morbid major depression (53%), any mood disorder (62-68%), generalized anxiety disorder (26%) and any anxiety disorder (42%) for both groups of participants with chronic PTSD. These rates of co-morbidity were higher than those found in non-PTSD comparison groups with similar MVA histories.     

Genetic and Environmental Contributions to Common Psychopathologies of Childhood and Adolescence: A Study of Twins and Their Siblings

We report findings based on analyses of self-reports of six common adolescent psychopathologies (attention deficit/hyperactivity disorder, ADHD; conduct disorder, CD; oppositional defiant disorder, ODD; generalized anxiety disorder, GAD; separation anxiety disorder, SAD; and major depressive disorder, MDD) in a sample of 1,162 male and female adolescent (12–19 years) twin pairs and 426 siblings. Prevalence statistics for past year and lifetime reports confirm differences between genders for CD, GAD, SAD, and MDD, and a lack of differences between twins and their non-twin siblings. Biometrical modeling was conducted to ascertain the relative influences of genes, and shared and non-shared environments contributing to these disorders. A more robust estimate of these parameters was obtained by including non-twin siblings. Age-specific thresholds were integrated into the analyses to appropriately model the developmental patterns of behavior. We found evidence for both genetic and non-shared environmental influences for all disorders. Shared environmental influences also seem to be important for MDD and lifetime GAD.