Orexin in the anxiety spectrum: association of a HCRTR1 polymorphism with panic disorder/agoraphobia, CBT treatment response and fear-related intermediate phenotypes

Preclinical studies point to a pivotal role of the orexin 1 (OX₁) receptor in arousal and fear learning and therefore suggest the HCRTR1 gene as a prime candidate in panic disorder (PD) with/without agoraphobia (AG), PD/AG treatment response, and PD/AG-related intermediate phenotypes. Here, a multilevel approach was applied to test the non-synonymous HCRTR1 C/T Ile408Val gene variant (rs2271933) for association with PD/AG in two independent case-control samples (total n = 613 cases, 1839 healthy subjects), as an outcome predictor of a six-weeks exposure-based cognitive behavioral therapy (CBT) in PD/AG patients (n = 189), as well as with respect to agoraphobic cognitions (ACQ) (n = 483 patients, n = 2382 healthy subjects), fMRI alerting network activation in healthy subjects (n = 94), and a behavioral avoidance task in PD/AG pre- and post-CBT (n = 271). The HCRTR1 rs2271933 T allele was associated with PD/AG in both samples independently, and in their meta-analysis (p = 4.2 × 10^-7), particularly in the female subsample (p = 9.8 × 10^-9). T allele carriers displayed a significantly poorer CBT outcome (e.g., Hamilton anxiety rating scale: p = 7.5 × 10^-4). The T allele count was linked to higher ACQ sores in PD/AG and healthy subjects, decreased inferior frontal gyrus and increased locus coeruleus activation in the alerting network. Finally, the T allele count was associated with increased pre-CBT exposure avoidance and autonomic arousal as well as decreased post-CBT improvement. In sum, the present results provide converging evidence for an involvement of HCRTR1 gene variation in the etiology of PD/AG and PD/AG-related traits as well as treatment response to CBT, supporting future therapeutic approaches targeting the orexin-related arousal system.

Impaired Interparental Relationships in Families of Children With Attention-Deficit/Hyperactivity Disorder (ADHD)

Abstract. Research on attention-deficit/hyperactivity disorder (ADHD) in children and adolescents has traditionally focused on the genetic and neurobiological aspects of the disorder, but the role of family relationships has been much less systematically examined. There is growing evidence that the quality of interparental relationships and a child’s ADHD symptoms are reciprocally related. Because the literature appears to be inconsistent, this meta-analysis aims to summarize previous research and assess whether there are robust differences in the quality of interparental relationships between parents of children with ADHD and parents of healthy children. This meta-analysis of 15 studies with 43 effect sizes revealed a small but significant difference ( d = .24), which indicates that parents of a child with ADHD report poorer relationship quality than parents of healthy children. This effect was moderated by the child’s age and did not depend on whether the child had a comorbid oppositional defiant disorder (ODD) or conduct disorder (CD). The causality of this relationship has yet to be determined.

Dissociation in victims of childhood abuse or neglect: a meta-analytic review

Childhood abuse and neglect are associated with dissociative symptoms in adulthood. However, empirical studies show heterogeneous results depending on the type of childhood abuse or neglect and other maltreatment characteristics. In this meta-analysis, we systematically investigated the relationship between childhood interpersonal maltreatment and dissociation in 65 studies with 7352 abused or neglected individuals using the Dissociative Experience Scale (DES). We extracted DES-scores for abused and non-abused populations as well as information about type of abuse/neglect, age of onset, duration of abuse, and relationship to the perpetrator. Random-effects models were used for data synthesis, and meta-regression was used to predict DES-scores in abused populations from maltreatment characteristics. The results revealed higher dissociation in victims of childhood abuse and neglect compared with non-abused or neglected subsamples sharing relevant population features (MAbuse = 23.5, MNeglect = 18.8, MControl = 13.8) with highest scores for sexual and physical abuse. An earlier age of onset, a longer duration of abuse, and parental abuse significantly predicted higher dissociation scores. This meta-analysis underlines the importance of childhood abuse/neglect in the etiology of dissociation. The identified moderators may inform risk assessment and early intervention to prevent the development of dissociative symptoms.

Verbal instructions override the meaning of facial expressions

Psychological research has long acknowledged that facial expressions can implicitly trigger affective psychophysiological responses. However, whether verbal information can alter the meaning of facial emotions and corresponding response patterns has not been tested. This study examined emotional facial expressions as cues for instructed threat-of-shock or safety, with a focus on defensive responding. In addition, reversal instructions were introduced to test the impact of explicit safety instructions on fear extinction. Forty participants were instructed that they would receive unpleasant electric shocks, for instance, when viewing happy but not angry faces. In a second block, instructions were reversed (e.g., now angry faces cued shock). Happy, neutral, and angry faces were repeatedly presented, and auditory startle probes were delivered in half of the trials. The defensive startle reflex was potentiated for threat compared to safety cues. Importantly, this effect occurred regardless of whether threat was cued by happy or angry expressions. Although the typical pattern of response habituation was observed, defense activation to newly instructed threat cues remained significantly enhanced in the second part of the experiment, and it was more pronounced in more socially anxious participants. Thus, anxious individuals did not exhibit more pronounced defense activation compared to less anxious participants, but their defense activation was more persistent.

Social and monetary incentives counteract fear-driven avoidance: Evidence from approach-avoidance decisions

BACKGROUND AND OBJECTIVES

The reduction of avoidance behavior is a central target in the treatment of anxiety disorders, but it has rarely been studied how approach of fear-relevant stimuli may be initiated. In two studies, the impact of hypothetical monetary and symbolic social incentives on approach-avoidance behavior was examined.

METHODS

In Study 1, individuals high or low on fear of spiders (N = 84) could choose to approach a fear-relevant versus a neutral stimulus, which were equally rewarded. In a subsequent micro-intervention, approaching the fear-relevant stimulus was differentially rewarded either by monetary or social incentives. In Study 2 (N = 76), initial incentives for approach were discontinued to investigate the stability of approach.

RESULTS

Hypothetical monetary and symbolic social incentives reduced or eliminated initial avoidance, even in highly fearful individuals. Approach resulted in a decrease of self-reported aversiveness towards the fear-relevant stimulus. However, even after successful approach, fearful individuals showed significant avoidance behavior when incentives for approach were discontinued.

LIMITATIONS

Future research should investigate the long-term effects of prolonged approach incentives on multiple levels of fear (e.g., self-report, behavioral, physiological). It should also be tested if such an intervention actually improves compliance with exposure based interventions.

CONCLUSIONS

The present findings highlight that incentives are useful to initiate initial approach towards a feared stimulus. Although incentive-based approach may neither fully eliminate avoidance nor negative feelings towards the feared stimulus, such operant interventions may set the stage for more extensive extinction training.

Threat vs. Threat: Attention to Fear-Related Animals and Threatening Faces

It is generally thought to be adaptive that fear relevant stimuli in the environment can capture and hold our attention; and in psychopathology attentional allocation is thought to be cue-specific. Such hypervigilance toward threatening cues or difficulty to disengage attention from threat has been demonstrated for a variety of stimuli, for example, toward evolutionary prepared animals or toward socially relevant facial expressions. Usually, specific stimuli have been examined in individuals with particular fears (e.g., animals in animal fearful and faces in socially fearful participants). However, different kinds of stimuli are rarely examined in one study. Thus, it is unknown how different categories of threatening stimuli compete for attention and how specific kinds of fears modulate these attentional processes. In this study, we used a free viewing paradigm: pairs of pictures with threat-related content (spiders or angry faces) or neutral content (butterflies or neutral faces) were presented side by side (i.e., spiders and angry faces, angry and neutral faces, spiders and butterflies, butterflies and neutral faces). Eye-movements were recorded while spider fearful, socially anxious, or non-anxious participants viewed the picture pairs. Results generally replicate the finding that unpleasant pictures more effectively capture attention in the beginning of a trial compared to neutral pictures. This effect was more pronounced in spider fearful participants: the higher the fear the quicker they were in looking at spiders. This was not the case for high socially anxious participants and pictures of angry faces. Interestingly, when presented next to each other, there was no preference in initial orientation for either spiders or angry faces. However, neutral faces were looked at more quickly than butterflies. Regarding sustained attention, we found no general preference for unpleasant pictures compared to neutral pictures.

Development and evaluation of a standardized peer-training in the context of peer review for quality assurance in work capacity evaluation

BACKGROUND

The German quality assurance programme for evaluating work capacity is based on peer review that evaluates the quality of medical experts' reports. Low reliability is thought to be due to systematic differences among peers. For this purpose, we developed a curriculum for a standardized peer-training (SPT). This study investigates, whether the SPT increases the inter-rater reliability of social medical physicians participating in a cross-institutional peer review.

METHODS

Forty physicians from 16 regional German Pension Insurances were subjected to SPT. The three-day training course consist of nine educational objectives recorded in a training manual. The SPT is split into a basic module providing basic information about the peer review and an advanced module for small groups of up to 12 peers training peer review using medical reports. Feasibility was tested by assessing selection, comprehensibility and subjective use of contents delivered, the trainers' delivery and design of training materials. The effectiveness of SPT was determined by evaluating peer concordance using three anonymised medical reports assessed by each peer. Percentage agreement and Fleiss' kappa (κ_m) were calculated. Concordance was compared with review results from a previous unstructured, non-standardized peer-training programme (control condition) performed by 19 peers from 12 German Pension Insurances departments. The control condition focused exclusively on the application of peer review in small groups. No specifically training materials, methods and trainer instructions were used.

RESULTS

Peer-training was shown to be feasible. The level of subjective confidence in handling the peer review instrument varied between 70 and 90%. Average percentage agreement for the main outcome criterion was 60.2%, resulting in a κ_m of 0.39. By comparison, the average percentage concordance was 40.2% and the κ_m was 0.12 for the control condition.

CONCLUSION

Concordance with the main criterion was relevant but not significant (p = 0.2) higher for SPT than for the control condition. Fleiss' kappa coefficient showed that peer concordance was higher for SPT than randomly expected. Nevertheless, a score of 0.39 for the main criterion indicated only fair inter-rater reliability, considerably lower than the conventional standard of 0.7 for adequate reliability.

Face-to-face: Perceived personal relevance amplifies face processing

The human face conveys emotional and social information, but it is not well understood how these two aspects influence face perception. In order to model a group situation, two faces displaying happy, neutral or angry expressions were presented. Importantly, faces were either facing the observer, or they were presented in profile view directed towards, or looking away from each other. In Experiment 1 (n = 64), face pairs were rated regarding perceived relevance, wish-to-interact, and displayed interactivity, as well as valence and arousal. All variables revealed main effects of facial expression (emotional > neutral), face orientation (facing observer > towards > away) and interactions showed that evaluation of emotional faces strongly varies with their orientation. Experiment 2 (n = 33) examined the temporal dynamics of perceptual-attentional processing of these face constellations with event-related potentials. Processing of emotional and neutral faces differed significantly in N170 amplitudes, early posterior negativity (EPN), and sustained positive potentials. Importantly, selective emotional face processing varied as a function of face orientation, indicating early emotion-specific (N170, EPN) and late threat-specific effects (LPP, sustained positivity). Taken together, perceived personal relevance to the observer-conveyed by facial expression and face direction-amplifies emotional face processing within triadic group situations.

Lab meets real life: A laboratory assessment of spontaneous thought and its ecological validity

People's minds frequently wander towards self-generated thoughts, which are unrelated to external stimuli or demands. These phenomena, referred to as "spontaneous thought" (ST) and "mind wandering" (MW), have previously been linked with both costs and benefits. Current assessments of ST and MW have predominantly been conducted in the laboratory, whereas studies on the ecological validity of such lab-related constructs and their interrelations are rare. The current study examined the stability of ST dimensions assessed in the lab and their predictive value with respect to MW, repetitive negative thought (uncontrollable rumination, RUM), and affect in daily life. Forty-three university students were assessed with the Amsterdam Resting State Questionnaire (2nd version) to assess ten ST dimensions during the resting state in two laboratory sessions, which were separated by five days of electronic ambulatory assessment (AA). During AA, individuals indicated the intensity of MW and RUM, as well as of positive and negative affect in daily life ten times a day. ST dimensions measured in the lab were moderately stable across one week. Five out of ten ST lab dimensions were predicted by mental health-related symptoms or by dispositional cognitive traits. Hierarchical linear models revealed that a number of ST lab dimensions predicted cognitive and affective states in daily life. Mediation analyses showed that RUM, but not MW per se, accounted for the relationship between specific ST lab dimensions and mood in daily life. By using a simple resting state task, we could demonstrate that a number of lab dimensions of spontaneous thought are moderately stable, are predicted by mental health symptoms and cognitive traits, and show plausible associations with categories of self-generated thought and mood in daily life.

Identifying Patterns in Complex Field Data

Abstract. Ambulatory assessment methods are well suited to examine how patients with panic disorder and agoraphobia (PD/A) undertake situational exposure. But under complex field conditions of a complex treatment protocol, the variability of data can be so high that conventional analytic approaches based on group averages inadequately describe individual variability. To understand how fear responses change throughout exposure, we aimed to demonstrate the incremental value of sorting HR responses (an index of fear) prior to applying averaging procedures. As part of their panic treatment, 85 patients with PD/A completed a total of 233 bus exposure exercises. Heart rate (HR), global positioning system (GPS) location, and self-report data were collected. Patients were randomized to one of two active treatment conditions (standard exposure or fear-augmented exposure) and completed multiple exposures in four consecutive exposure sessions. We used latent class cluster analysis (CA) to cluster heart rate (HR) responses collected at the start of bus exposure exercises (5 min long, centered on bus boarding). Intra-individual patterns of assignment across exposure repetitions were examined to explore the relative influence of individual and situational factors on HR responses. The association between response types and panic disorder symptoms was determined by examining how clusters were related to self-reported anxiety, concordance between HR and self-report measures, and bodily symptom tolerance. These analyses were contrasted with a conventional analysis based on averages across experimental conditions. HR responses were sorted according to form and level criteria and yielded nine clusters, seven of which were interpretable. Cluster assignment was not stable across sessions or treatment condition. Clusters characterized by a low absolute HR level that slowly decayed corresponded with low self-reported anxiety and greater self-rated tolerance of bodily symptoms. Inconsistent individual factors influenced HR responses less than situational factors. Applying clustering can help to extend the conventional analysis of highly variable data collected in the field. We discuss the merits of this approach and reasons for the non-stereotypical pattern of cluster assignment across exposures.

Facing two faces: Defense activation varies as a function of personal relevance

It can be unsettling to be watched by a group of people, and when they express anger or hostility, this can prime defensive behavior. In contrast, when others smile at us, this may be comforting. This study tested to which degree the impact of facial expressions (happy, neutral, and angry) varies with the personal relevance of a social situation. Modelling a triadic situation, two faces looked either directly at the participant, faced each other, or they were back to back. Results confirmed that this variation constitutes a gradient of personal relevance (directed frontally > towards > away), as reflected by corresponding defensive startle modulation and autonomic nervous system activity. This gradient was particularly pronounced for angry faces and it was steeper in participants with higher levels of social anxiety. Thus, sender-recipient constellations modulate the processing of facial emotions in favor of adequate behavioral responding (e.g., avoidance) in group settings.

The role of treatment delivery factors in exposure-based cognitive behavioral therapy for panic disorder with agoraphobia

Treatment delivery factors (i.e., therapist adherence, therapist competence, and therapeutic alliance) are considered to be important for cognitive behavioral therapy (CBT) for panic disorder and agoraphobia (PD/AG). In the current study, four independent raters conducted process evaluations based on 168 two-hour videotapes of 84 patients with PD/AG treated with exposure-based CBT. Two raters evaluated patients' interpersonal behavior in Session 1. Two raters evaluated treatment delivery factors in Session 6, in which therapists provided the rationale for conducting exposure exercises. At the 6-month follow-up, therapists' adherence (r=0.54) and therapeutic alliance (r=0.31) were significant predictors of changes in agoraphobic avoidance behavior; therapist competence was not associated with treatment outcomes. Patients' interpersonal behavior in Session 1 was a significant predictor of the therapeutic alliance in Session 6 (r=0.17). The findings demonstrate that treatment delivery factors, particularly therapist adherence, are relevant to the long-term success of CBT for PD/AG.

Cognitive and Emotional Processing in Narratives of Women Abused by Intimate Partners

This study examined relationships between cognitive and emotional processing with changes in pain and depression among intimate partner violence survivors. Twenty-five women who wrote about their most traumatic experiences completed measures of pain and depressive symptoms before the first writing session and again 4 months following the last writing session. Reduced pain was significantly associated with less use of positive and negative emotion words. Relationships between cognitive and emotional aspects of writing with changes in depressive symptoms fell short of statistical significance. The results suggest that emotional processing in narrative writing predicts changes in pain in intimate partner violence survivors.

Influence of perceptual cues and conceptual information on the activation and reduction of claustrophobic fear

BACKGROUND

Fear reactions in phobic patients can be activated by specific perceptual cues (C) or by conceptual fear-related information (I). An earlier study with spider phobic participants documented that perceptual stimuli are particularly potent to trigger fear responses. Because fear of spiders is activated by very circumscribed stimuli, we set out to investigate whether another phobia with more contextual fear-elicitation (i.e., a situational phobia) would yield similar patterns. Thus, we investigate the two paths of fear activation (cues vs. information) and fear reduction during exposure in claustrophobic patients.

METHOD

Forty-eight claustrophobic patients and 48 healthy control participants were randomly assigned to one of three virtual reality exposure conditions: C, I, or a combination of both (CI). Exposure lasted 5 min and was repeated 4 times. Self-report and physiological reactions were assessed.

RESULTS

Claustrophobic patients experienced more initial self-reported fear when confronted with fear-relevant perceptual cues than conceptual information, when the perceptual cues were combined with conceptual information there was no significant enhancement. Furthermore, fear habituated more in the perceptual condition. For the physiological parameters, groups differed and in claustrophobic patients heart rate decreased differently in the conditions.

LIMITATIONS

Longer exposure duration and long-term effects of the manipulation were not investigated.

CONCLUSION

We found similar patterns in a situational phobia as compared to a specific-cue related phobia (animal type). Thus, once more this highlights the central role of visual cues in phobic fear and the potential of virtual reality for conducting exposure therapy.

Representation of Patients' Hand Modulates Fear Reactions of Patients with Spider Phobia in Virtual Reality

Embodiment (i.e., the involvement of a bodily representation) is thought to be relevant in emotional experiences. Virtual reality (VR) is a capable means of activating phobic fear in patients. The representation of the patient's body (e.g., the right hand) in VR enhances immersion and increases presence, but its effect on phobic fear is still unknown. We analyzed the influence of the presentation of the participant's hand in VR on presence and fear responses in 32 women with spider phobia and 32 matched controls. Participants sat in front of a table with an acrylic glass container within reaching distance. During the experiment this setup was concealed by a head-mounted display (HMD). The VR scenario presented via HMD showed the same setup, i.e., a table with an acrylic glass container. Participants were randomly assigned to one of two experimental groups. In one group, fear responses were triggered by fear-relevant visual input in VR (virtual spider in the virtual acrylic glass container), while information about a real but unseen neutral control animal (living snake in the acrylic glass container) was given. The second group received fear-relevant information of the real but unseen situation (living spider in the acrylic glass container), but visual input was kept neutral VR (virtual snake in the virtual acrylic glass container). Participants were instructed to touch the acrylic glass container with their right hand in 20 consecutive trials. Visibility of the hand was varied randomly in a within-subjects design. We found for all participants that visibility of the participant's hand increased presence independently of the fear trigger. However, in patients, the influence of the virtual hand on fear depended on the fear trigger. When fear was triggered perceptually, i.e., by a virtual spider, the virtual hand increased fear. When fear was triggered by information about a real spider, the virtual hand had no effect on fear. Our results shed light on the significance of different fear triggers (visual, conceptual) in interaction with body representations.

Perception of children's faces with unilateral coronal synostosis--an eye-tracking investigation

PURPOSE

Premature unilateral coronal craniosynostosis results in distinctive cranial and facial abnormalities of varying severity, including orbital dystopia and an abnormal head shape. As the face is affected, these children may encounter stigmatization. To avoid this scenario, many parents elect for their child to undergo surgical correction. Laypeople's perception of children with either untreated or treated unilateral coronal craniosynostosis (UCS) has not yet been objectively evaluated.

METHODS

This study introduces eye tracking as an objective instrument in order to evaluate the perception of 14 children with coronal synostosis, both pre- and postoperatively. Age-matched healthy children served as a control group. Using standardized photos, the involuntary eye movements and the fixations of 30 unaffected laypeople were evaluated.

RESULTS

In the untreated children, whose faces were characterized by striking orbital dystopia, the eyes drew more attention than those of the healthy children. The results of our study demonstrate that the operative correction of unilateral coronal synostosis results in the normalization of the asymmetry of the fronto-orbital region, whereas the C-shaped deformity of the midface, which is not addressed via surgery, subsequently attracts more attention.

CONCLUSION

Eye tracking objectively evaluates both the perception of craniofacial abnormalities and the extent of the approximation of normality after surgical correction. We introduce eye tracking as an objective measurement tool for craniofacial abnormalities for the first time.

Anxiety and rumination moderate menstrual cycle effects on mood in daily life

Evidence for menstrual cycle-related mood fluctuations in the general population of women has been mixed. While most previous research has relied on retrospective self-report and did not consider possible moderators, the present study aimed to examine cycle-related mood variations in daily life and possible moderating effects of anxiety and trait rumination. Fifty-nine women with natural menstrual cycles, aged 18-44 years, were examined between January and October, 2012. Mood components of calmness, positive valence, energetic-arousal, and irritability were assessed, using smartphones, by ambulatory assessment ten times per day on eight days across the cycle. The menstrual, follicular, ovulatory, and late luteal phases were each covered by two consecutive assessment days. Moderators were assessed with questionnaires. Hierarchical linear models (HLMs) revealed higher calmness in the luteal and menstrual than in the follicular and ovulatory phase, while the menstrual cycle did not exhibit significant main effects on other mood components. Anxiety and ruminative self-reflection moderated the association between menstrual cycle and all mood variables. Specifically, highly anxious and ruminative women showed an increase in irritability, while women with lower anxiety and lower rumination were protected against mood deterioration toward the end of the cycle. Further research could examine whether reducing anxiety and rumination helps to prevent premenstrual syndrome-related syndromes.

Avoidant decision-making in social anxiety disorder: A laboratory task linked to in vivo anxiety and treatment outcome

Recent studies on reward-based decision-making in the presence of anxiety-related stimuli demonstrated that approach-avoidance conflicts can be assessed under controlled laboratory conditions. However, the clinical relevance of these decision conflicts has not been demonstrated. To this end, the present study investigated avoidant decisions in treatment-seeking individuals with social anxiety disorder (SAD). In a gambling task, advantageous choices to maximize gains were associated with task-irrelevant angry faces and disadvantageous choices with happy faces. The clinical relevance of avoidant decisions for in vivo anxiety in a social stress situation (public speaking) were examined (n = 44). In a subsample (n = 20), the predictive value for a reduction of avoidance following behavioral therapy was also evaluated. Results indicated a close link between more frequent avoidant decisions and elevated in vivo anxiety. Moreover, individuals who showed a deficit in the goal-directed adjustment of their decisions also showed higher and sustained distress during the social stressor and reported less decrease of avoidance following treatment. The findings highlight the importance of an avoidant decision-making style for the experience of acute distress and the maintenance of avoidance in SAD. Assessing avoidant decision-making may help to predict the response to behavioral treatments.

5HTT is associated with the phenotype psychological flexibility: results from a randomized clinical trial

Adaption to changing environments is evolutionarily advantageous. Studies that link genetic and phenotypic expression of flexible adjustment to one's context are largely lacking. In this study, we tested the importance of psychological flexibility, or goal-related context sensitivity, in an interaction between psychotherapy outcome for panic disorder with agoraphobia (PD/AG) and a genetic polymorphism. Given the established role of the 5HTT-LPR polymorphism in behavioral flexibility, we tested whether this polymorphism (short group vs. long group) impacted therapy response as a function of various endophenotypes (i.e., psychological flexibility, panic, agoraphobic avoidance, and anxiety sensitivity). Patients with PD/AG were recruited from a large multicenter randomized controlled clinical trial on cognitive-behavioral therapy. Pre- to post-treatment changes by 5HTT polymorphism were analyzed. 5HTT polymorphism status differentiated pre- to post-treatment changes in the endophenotype psychological flexibility (effect size difference d = 0.4, p < 0.05), but none of the specific symptom-related endophenotypes consistently for both the intent-to-treat sample (n = 228) and the treatment completers (n = 194). Based on the consistency of these findings with existing theory on behavioral flexibility, the specificity of the results across phenotypes, and the consistency of results across analyses (i.e., completer and intent to treat), we conclude that 5HTT polymorphism and the endophenotype psychological flexibility are important variables for the treatment of PD/AG. The endophenotype psychological flexibility may help bridge genetic and psychological literatures. Despite the limitation of the post hoc nature of these analyses, further study is clearly warranted.

Dimensional structure of bodily panic attack symptoms and their specific connections to panic cognitions, anxiety sensitivity and claustrophobic fears

BACKGROUND

Previous studies of the dimensional structure of panic attack symptoms have mostly identified a respiratory and a vestibular/mixed somatic dimension. Evidence for additional dimensions such as a cardiac dimension and the allocation of several of the panic attack symptom criteria is less consistent. Clarifying the dimensional structure of the panic attack symptoms should help to specify the relationship of potential risk factors like anxiety sensitivity and fear of suffocation to the experience of panic attacks and the development of panic disorder.

METHOD

In an outpatient multicentre study 350 panic patients with agoraphobia rated the intensity of each of the ten DSM-IV bodily symptoms during a typical panic attack. The factor structure of these data was investigated with nonlinear confirmatory factor analysis (CFA). The identified bodily symptom dimensions were related to panic cognitions, anxiety sensitivity and fear of suffocation by means of nonlinear structural equation modelling (SEM).

RESULTS

CFA indicated a respiratory, a vestibular/mixed somatic and a cardiac dimension of the bodily symptom criteria. These three factors were differentially associated with specific panic cognitions, different anxiety sensitivity facets and suffocation fear.

CONCLUSIONS

Taking into account the dimensional structure of panic attack symptoms may help to increase the specificity of the associations between the experience of panic attack symptoms and various panic related constructs.