Agoraphobic avoidance and panic frequency as predictors of laboratory induced panic reactions

This study examined the importance of agoraphobic avoidance and frequency of panic as predictors of psychological and physiological responses of panic sufferers to a laboratory based provocation procedure. Psychophysiologic comparisons were made between 22 panic disorder patients and 15 controls, at baseline and across three periods of carbon dioxide gas inhalations (1, 3, 5%; balance oxygen). Subjective measures of anxiety, frightening cognitions and body sensations were obtained across the phases. Physiological measures of minute ventilation, breathing rate, tidal volume, end tidal CO₂ and heart rate were also obtained. Between group comparisons revealed significant differences between the groups on the subjective measures with no significant differences occurring on the physiological measures. Within group analyses revealed that pre-session questionnaire measures of agoraphobia avoidance and panic frequency predicted the degree of anxiety, frightening sensations and cognitions during baseline and 5% CO₂ inhalation. The results indicated that both self-reported agoraphobic avoidance and panic frequency are strong clinical predictors of psychological reactions of panic sufferers during laboratory provocation.     

Panic symptoms in asthma and panic disorder: a preliminary test of the dyspnea-fear theory.

Ley's (Behaviour Research and Therapy, 27, 549-554, 1989) dyspnea-fear theory was tested on three groups of subjects: 10 with panic disorder, 24 with asthma, and 12 who were nonanxious and nonasthmatic, using measures of pulmonary function, muscle tension; and self-report measures of generalized anxiety, dyspnea, and psychopathology. Results are supportive of dyspnea-fear theory for asthmatics but not for individuals with panic disorder. Differences between groups on panic/fear measures were explained by a combination of general anxiety and dyspnea. Within-group regression analyses showed that only generalized anxiety symptoms contributed significantly to scores on the Asthma Symptom Checklist scale of panic/fear within the panic disorder group; while only dyspnea contributed to panic/fear among asthmatics. Additional results show that panic disorder subjects performed normally on pulmonary function tests but reported respiratory symptoms as severe as did asthmatics. Compared with normal subjects, both patient groups displayed lower correlations between self-rated symptoms of bronchoconstriction and objective pulmonary measures. Panic disorder subjects showed a negative relationship between pulmonary function and hyperventilation symptoms, suggesting a heightened sensitivity to, and discomfort with, sensations associated with normal pulmonary function. Asthmatics displayed a significant relationship between degree of airway obstruction and both trapezius surface EMG and ratings of hyperventilation symptoms.     

The role of safety cues in mediating the response to inhalations of CO2 in agoraphobics

Eighteen subjects meeting DSM-III-R criteria for panic disorder with agoraphobia were randomly allocated to either a safety or non-safety condition and underwent 15 min inhalations of 5.5% CO2 in air. In the safety condition, both a senior and junior experimenter were present, the junior experimenter was presented as a professional, and subjects were in personal contact with the senior experimenter throughout the procedure. In the non-safety condition, the senior experimenter left on a bogus emergency, the junior experimenter was introduced as a "student" and was dressed casually, and subjects were alone in the experimental room throughout the procedure. Despite these dramatic manipulations, there was no significant difference between groups on either the number of subjects experiencing a panic attack or on pre-inhalation safety scores. However, a median-split analysis on safety scores indicated that those subjects who perceived themselves to be less safe before the inhalation were more likely to experience a panic attack.     

Differences in reported symptom profile between panic disorder and other DSM-III-R anxiety disorders.

Previous research has indicated that reports of panic attacks are associated with a different set of symptoms to reports of generalized anxiety. The present two studies attempted to extend these findings to specific (situational) fears. In Study 1, 55 subjects with panic disorder were compared on their symptom profile during their panic attacks to 65 subjects with other anxiety disorders [simple phobia, social phobia and obsessive-compulsive disorder (OCD)] during response to their feared cue. The results indicated that, compared to subjects with other anxiety disorders, subjects with panic disorder were more likely to report parasthesias, dizziness, faintness, unreality, dyspnea, fear of dying and fear of going crazy/losing control. In Study 2, 90 subjects meeting diagnostic criteria for both panic disorder and another anxiety disorder (simple phobia, social phobia or OCD) were compared on the symptoms experienced during their unexpected panic attacks and their situationally-triggered fears respectively. Combining the symptoms found in Study 1 to differ between the groups into a linear combination, there was a significant interaction found between the type of fear reaction (panic attack vs cued fear response) and symptom group. Taken together, these findings suggest that reports of unexpected panic attacks associated with panic disorder are characterized by a different symptom profile to reports of specific fear reactions that are part of a phobic disorder or OCD.     

THE SUSCEPTIBILITY OF INTELLECTUAL FUNCTIONS TO A DEPRESSANT DRUG

F rankenhaeuser , M., and B eckman , M. The susceptibility of intellectual functions to a depressant drug. Scand. J. Psychol ., 1961, 2 , 93–99.—The performance of 32 subjects in tests on four intellectual factors (verbal, numerical, inductive and spatial) during the inhalation of nitrous oxide (30 per cent N₂O and 70 per cent O₂) and a control mixture (30 per cent N₂ and 70 per cent O₂) were compared . The drug caused a highly significant deterioration in the performance of all four tests. Both speed and accuracy of performance were impaired. The problem of a possible differential susceptibility to the drug of the various intellectual functions wag attacked by a statistical analysis of the differences between the tests with regard to changes in performance during drug inhalation. No reliable differences in extent of impairment between the four tests could be demonstrated.     

Provocation of panic: three elements of the panic reaction in four anxiety disorders

Subjects with agoraphobia (N = 25), panic disorder (N = 25), social phobia (N = 19) or generalized anxiety disorder (N = 10) and controls with no psychiatric history (N = 16) underwent two provocation tests, voluntary hyperventilation and inhalation of 5% CO2 in air, and three experimental control conditions. They were measured on three elements of the panic reaction: somatic symptoms, psychic anxiety and fears of impending doom, and on a standard YES/NO measure of panic attack. The provocation conditions produced increased somatic symptoms and psychic anxiety across all groups relative to the control conditions. The agoraphobic and panic disorder groups showed a significantly greater increase in fears of impending doom from control to provocation conditions than the social phobic and GAD patients. This difference was not observed on measures of somatic symptoms or psychic anxiety. The present results provide some support for the theory that panic attacks result from the catastrophic misinterpretation of anxious symptoms, in this case produced by the two provocation tests.     

Anxiety induced by cardiac perceptions in patients with panic attacks: a field study

In panic disorder bodily sensations appear to play an important role as a trigger for anxiety. In our psychophysiological model of panic attacks we postulate the following vicious circle: individuals with panic attacks perceive even quite small increases in heart rate and interpret these changes as being catastrophic. This elicits anxiety and a further increase in heart rate. To evaluate this model we conducted a field study of 28 subjects with panic attacks and 20 healthy controls. A 24 hr ambulatory ECG was recorded and the subjects were instructed to report any cardiac perceptions during this period and to rate the anxiety elicited by these perceptions. The incidence of cardiac perceptions was about the same in both groups, but only subjects with panic attacks reported anxiety associated with such perceptions. Analysis of the ECGs revealed that in both groups heart rate accelerations preceded cardiac perceptions. Following cardiac perceptions, the healthy controls showed a heart rate deceleration, whereas the subjects with panic attacks had a further acceleration. This heart rate increase after cardiac perceptions was positively related to the level of anxiety elicited by the perceptions. These results provide clear evidence in support of the vicious circle model of panic attacks.     

Nocturnal panic: response to hyperventilation and carbon dioxide challenges

To examine the role of ventilatory response in nocturnal panic, subjects experiencing nocturnal panic were compared with those who experienced daytime panic attacks only. In particular, measures of chronic hyperventilation (baseline pCO2) and CO2 hypersensitivity (response to ventilatory challenges) were assessed. Subjective and psychophysiological measures were obtained during baseline, forced hyperventilation, and carbon dioxide inhalation phases of a standardized laboratory-based assessment. The groups did not differ with respect to subjective or physiological measures or to the frequency with which panic occurred during the assessment. The results do not lend support to models that emphasize central CO2 hypersensitivity and chronic hyperventilation as primary mechanisms underlying nocturnal panic.     

The effects of inhaling a 35 per cent CO2-65 per cent O2 mixture upon anxiety level in neurotic patients

Wolpe has reported the use of a 35 per cent CO₂-65 per cent O₂ mixture to relax patients who cannot otherwise be relaxed sufficiently to allow desensitization. In this investigation, the anxiety-reducing effects of single inhalations of a 35 per cent CO₂-65 per cent O₂ were studied on twelve patients, all of whom had been diagnosed by their doctors as having a high level of anxiety. On the basis of the subjects' ratings, this mixture was more effective than was an equal volume of air which was breathed through the same apparatus as was the experimental mixture. Evidence is offered which suggests that the decrement in anxiety which followed administration of the 35 per cent CO₂-65 per cent O₂ mixture was due to some effect of the gas other than the hyperventilation which it induces.     

Does coping predict CO2-induced panic in patients with panic disorder?

Patients with panic disorder (PD) show maladaptive coping but the role of coping in the pathogenesis of panic is unclear. This study examined general coping and panic-specific coping as predictors of fear responding to CO2 inhalation. Subjective and physiological responses including panic attacks were assessed in 45 patients with PD and 45 matched nonclinical controls. Measures of coping were the primary predictors used in the analyses. Consistent with other reports, patients with PD reported increased emotion-focused coping and there was an association between emotion-focused coping and subjective reactivity. However, only panic-specific coping predicted panic attacks in response to the CO2 challenge.     

Breathing retraining, exposure and a combination of both, in the treatment of panic disorder with agoraphobia

The present study investigates the differential effectiveness of three treatment packages for agoraphobia. Patients suffering from panic disorder with agoraphobia (DSM-III-R) received one of three treatments: Breathing Retraining with Cognitive Restructuring (BRCR), graded self-exposure in vivo (EXP), or a combination of BRCR and EXP. Treatments consisted of 8 sessions. Assessments consisted of self-report measures for panic, phobic anxiety and avoidance, depression, general anxiety, somatic complaints and fear of bodily sensations, and of two respiratory measures (respiratory rate and alveolar pCO₂).

The treatments resulted in a reduction in symptomatology on all self-report measures, except panic frequency, and in a decrease in respiratory rate. There was no evidence for a differential efficacy for any of the treatments on any of the variables. Contrary to expectation, and at odds with findings from earlier studies, BRCR had no significant effect on panic frequency. A detailed comparison of sample characteristics of patients in our study and previous studies, did not yield insight into possible causes for the failure to replicate earlier results. The limited effectiveness of breathing retraining in reducing panic, as observed in the present study, leads us to conclude that the role of hyperventilation in panic is less important than previously thought.     

Cognitive behavioral therapy for panic disorder and comorbidity: more of the same or less of more?

This study compared the effects of a higher dose of cognitive behavioral therapy (CBT) for panic disorder versus CBT for panic disorder combined with "straying" to CBT for comorbid disorders in individuals with a principal diagnosis of panic disorder with or without agoraphobia. Sixty-five participants were randomly assigned to one of two treatment conditions, either CBT focused solely upon panic disorder and agoraphobia or CBT that simultaneously addressed panic disorder and agoraphobia and, to a lesser degree, the most severe comorbid condition. Results indicated a significant reduction in panic disorder severity and a decline in severity of comorbid diagnoses across both treatment conditions. However, individuals receiving CBT focused only on panic disorder were more likely to meet high end-state functioning at post-treatment, even in intent-to-treat analyses, and report zero panic attacks at the 1-year follow-up, although this effect was not retained in intent-to-treat analyses. At follow-up, CBT focused only on panic disorder yielded more substantial improvement in the most severe baseline comorbid condition, although not in intent-to-treat analyses, and a greater proportion of individuals in this treatment condition were rated as having no comorbid diagnoses, even in intent-to-treat analyses. These findings raise the possibility that remaining focused on CBT for panic disorder may be more beneficial for both principal and comorbid diagnoses than combining CBT for panic disorder with 'straying' to CBT for comorbid disorders.     

Panic-disordered subjects' perceptions of film: a repertory grid study

Clinical research into panic attacks over the past two decades has led to the hypothesis that panic-disordered subjects may have a lower threshold to separation anxiety than normals. This hypothesis was investigated by measuring panic-disordered and normal subjects' reactions to viewing a film of a potentially anxiety-provoking situation. The extent to which individuals construe film through identification with the narrative's characters was also examined. To gauge these reactions a repertory grid was administered to 11 subjects with a history of panic disorder and 12 controls after they had watched a half-hour episode from a feature film in which a divorced couple fight acrimoniously over custody of their 17-yr.-old daughter. Five elements were characters mentioned in the film and two were of 'self,' one in a secure and another in an insecure situation. Ten constructs were elicited by a triadic sorting procedure and four were supplied. Ratings of elements on all constructs were subjected to a principal components analysis (INGRID). While the construals of the two groups were essentially similar, there were differences between them in terms of the perceived salience of the film's characters. Panic-disordered subjects also construed themselves as more insecure than did the normals. The results affirm the use of the repertory grid in the study of panic disorder and in the analysis of the perception of filmed events.     

Selective Processing of Threat Cues in Subjects with Panic Attacks

Abstract

Previous research has demonstrated that patients with generalised anxiety disorder, phobias, and obsessive-compulsive disorder show an attentional bias towards threat cues related to their respective disorders. Two studies are presented that used a modified Stroop colour naming task to assess attentional bias in subjects with panic attacks. In Study 1, 24 panic disorder patients and 24 normal controls were presented three cards containing threat words related to physical harm, separation, or social embarrassment. Colour naming times were compared between these cards and control cards containing matched non-threat words. Reaction time differences in the two groups were in opposite directions, patients tending to be slower in colour naming threat words, and controls, faster. In Study 2, 18 non-clinical panickers and 18 controls were presented cards containing physical threat words, neutral control words, or colour words, respectively. Panickers showed greater interference than controls in colour naming threat words but not in colour naming colour words. The results are consistent with an attentional bias for threat-related material in subjects with panic attacks. Implications for psychophysiological models of 'spontaneous' panic attacks are discussed.     

Increased cardiac awareness in panic disorder.

We investigated cardiac perception in panic disorder with both self-report and objective measures. In Study 1, 120 patients with panic disorder, 86 infrequent panickers, and 38 patients with other anxiety disorders reported greater cardiac and gastrointestinal awareness than 62 normal control subjects. Subjects with panic attacks reported greater cardiac awareness, but not gastrointestinal awareness, than those with other anxiety disorders. Studies 2 and 3 included a test of heart rate perception in which subjects silently counted their heart-beats without taking their pulse. In Study 2, 65 panic disorder patients showed better performance than 50 infrequent panickers, 27 patients with simple phobias, and 46 normal control subjects. No group differences were found in ability to estimate time intervals. In Study 3, 13 patients with panic disorder and 15 with generalized anxiety disorder showed better heart rate perception than 16 depressed patients.     

Nonclinical panic in college students: an investigation of prevalence and symptomatology

This article presents data on the prevalence and symptomatology of panic attacks and panic disorder (PD) in a large nonclinical sample (n = 2,375) of college students. Results showed that approximately 12% of the sample had experienced at least one unexpected panic attack and that 2.36% met DSM-III-R criteria for panic disorder. Although there were no sex differences in overall panic attack prevalence, men reported significantly more panic-related worry than women, and women reported a higher panic frequency than men. Compared to subjects who met DSM-III-R criteria for PD, infrequent panickers presented with fewer panic symptoms, fewer panic episodes, less panic-related worry, lower anxiety sensitivity, and less panic-related avoidance. Moreover, compared with PD subjects, the infrequent panickers were much less likely to report fears of dying, going insane, and derealization during a panic attack. The findings provide preliminary support for the role of anxious apprehension as a psychological vulnerability factor in the pathogenesis of panic disorder.     

Cognitive Behavioral Treatment of Panic Disorder and Agoraphobia in a Multiethnic Urban Outpatient Clinic: Initial Presentation and Treatment Outcome

Few studies examine the effectiveness of panic control treatment across diverse ethnic groups. In this paper we present data on 40 patients (African American, n = 24; Caucasian, n = 16) with panic disorder and comorbid agoraphobia who presented at an anxiety disorder clinic in an inner-city area. On initial assessment both groups were similar on psychometric measures, and both groups moderately improved with treatment though significant residual symptoms remained. We illustrate, through case examples, a variety of clinical issues that need to be addressed when providing treatment to multiethnic African American clients with panic disorder and agoraphobia.     

The effect of simulation exercises on the control of aggressive behaviour in children

Abstract.— The subjects consisted of two. matched, extremely aggressive (experimental = ExG and control = CoG) groups of twelve 8–year-old boys. and of one criterion group (CrG) of extrovert, well-controlled boys. Video-tape recording of behaviour was used both in pretest (T₁) and post-test (T₂). Between T₁ and T₂ the ExG was submitted to simulation exercises of 8 lessons given in a period of four weeks. The exercises consisted in social problem solutions on the purely cognitive (imaginary and symbolic) level and in role-playing (behavioral level). The hypothesis was that the combination of cognitive training and observational learning with the aim of making children realise alternatives to aggression in coping with thwarting situations and their after-effects. would influence individuals with strong aggressive habits to abandon theiraggressive reactions in favour of more constructive behaviour. As to aggression, the results supported the hypothesis. For constructive behaviour, (1) the ExG maintained the samelevel of control of social behaviour in T₁ and T₂, while a significant drop occurred in the GoC, and (2) the strategies of problem solution improved significantly in the ExG. In T₂, the behaviour of the ExG resembled more closely that of the CoG than the behaviour of the CrG, as hypothesized.