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.     

Heartbeat perception in panic disorder: a reanalysis

This article describes a reanalysis of seven studies on heart beat perception (HBP) in panic disorder. The pooled sample had 709 participants from eight diagnostic categories. Accurate HBP was uncommon, but more prevalent among panic disorder patients than among healthy controls, depressed patients, patients with palpitations and individuals with infrequent panic attacks. No differences were found between panic disorder patients and patients with other anxiety disorders. Accurate perceivers had higher anxiety sensitivity scores than inaccurate perceivers. The data remain inconclusive as to whether perceived heart rate is correlated with anxiety in inaccurate perceivers. Physical exercise, distraction, variations in instructions and treatment each influenced HBP. However, the influence was different than previously thought. Finally, it is suggested that HBP may be understood in terms of schema-guided information processing.     

Anxiety sensitivity and panic attacks in a nonclinical population

In the present study, we administered the Anxiety Sensitivity Index (ASI) and a modified version of the Panic Attack Questionnaire (PAQ) to 425 college students to determine whether high anxiety sensitivity ('fear of fear') occurs in the absence of a history of unpredictable ('spontaneous') panic attacks, or whether such attacks are a necessary precursor to high anxiety sensitivity. Based on their ASI scores, subjects were assigned to either the high, medium, or low anxiety sensitivity groups. High anxiety sensitivity subjects more frequently reported both a personal and family history of panic than did subjects in the other groups. Nevertheless, two-thirds of the high anxiety sensitivity subjects had never experienced an unpredictable panic attack. This suggests that the fear of anxiety can be acquired in ways other than through personal experience with panic.     

Are current theories of panic falsifiable?

The authors examine 6 theories of panic attacks as to whether empirical approaches are capable of falsifying them and their heuristic value. The authors conclude that the catastrophic cognitions theory is least falsifiable because of the elusive nature of thoughts but that it has greatly stimulated research and therapy. The vicious circle theory is falsifiable only if the frightening internal sensations are specified. The 3-alarms theory postulates an indeterminate classification of attacks. Hyperventilation theory has been falsified. The suffocation false alarm theory lacks biological parameters that unambiguously index dyspnea or its distinction between anticipatory and panic anxiety. Some correspondences postulated between clinical phenomena and brain areas by the neuroanatomical hypothesis may be falsifiable if panic does not depend on specific thoughts. All these theories have heuristic value, and their unfalsifiable aspects are capable of modification.     

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.     

Emotional processing and panic

In this paper Rachman's concept of emotional processing was extended and a model highlighting the psychological operations underpinning processing was specified. Using this model, the aim was to investigate, by means of a questionnaire, whether patients with panic disorder (n=50) have more emotional processing difficulties than two samples of healthy controls (London, n=406; Aberdeen, n=125). The panic disorder group did have significantly more emotional processing difficulties than the control groups, showing a marked tendency to control feelings of anger, unhappiness and anxiety. Three emotional processing dimensions distinguished the panic from the control groups: greater control of emotional experiences ('smothering' or 'bottling up' emotions), greater awareness of feelings and more difficulties in labelling emotions. The authors hypothesise that emotional processing deficits act as a vulnerability factor for developing panic attacks.     

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.     

Physiological and psychological reactivity in women with asthma: the effects of anxiety and menstrual cycle phase.

The relation between menstrual cycle timing, panic attacks, and diagnosis of asthma was explored in this study. Women with or without asthma and with or without a history of panic attacks engaged in a psychophysiological task during either the intermenstrual or premenstrual cycle phase and completed self-report measures of menstrual symptoms and attitudes, general psychological symptoms, and attitudes toward illness. No significant differences were identified for psychological or psychophysiological measures with menstrual cycle phase as a factor. However, women with both asthma and a history of panic attacks reported more general psychological distress than women in the other groups, and more state anxiety than controls. Women in the asthma, asthma and panic, and panic groups reported higher anxiety sensitivity than the control group. After listening to asthma-related scenes, women with asthma exhibited a decrease in peak expiratory air flow, and women with asthma and panic exhibited increased skin conductance response magnitude. Implications for the role of anxiety in lung function are discussed, as well as directions for future research with asthma and anxiety populations.     

Anxiety sensitivity and nonclinical panic attacks

The present study examined anxiety sensitivity in relation to trait anxiety and the occurrence of nonclinical panic attacks in 265 subjects. Fifty percent of high anxiety sensitivity subjects reported panic attacks (both cued and spontaneous) in the past year. In addition, almost 42% of subjects with high anxiety sensitivity but no history of panic reported a high level of trait anxiety concerning physical danger. The results suggest that anxiety sensitivity is frequently not independent of other forms of anxiety.     

Attentional bias and anxiety in individuals with coronary heart disease

This study examined whether in an emotional Stroop task, individuals with coronary heart disease (CHD) would show greater attention towards the threatening words related to their disease than healthy persons, and if such an attentional bias is associated with anxiety. An emotional Stroop task with threatening words related to CHD as well as positive, negative and neutral words was administered to 35 individuals with CHD and 35 healthy controls. Additionally, the original Stroop task, the Beck anxiety inventory and the state-trait anxiety inventory were administered. The results indicated an attentional bias towards threatening words related to CHD in the individuals with CHD. They experienced higher interference than healthy participants from threatening words related to CHD but not from positive or negative words. Moreover, the level of interference was associated with their level of anxiety, and a vicious circle may exist in this association. In addition, results indicated a possible deficit of executive functioning among individuals with CHD. Attentional bias, as well as its association with anxiety, and an indication of deficit in executive functioning among individuals with CHD might be the risk factors for these individuals’ quality of life and for further development of their disease.     

Physiological and symptom responses to hyperventilation: A comparison of frequent and infrequent panickers

Ten subjects with panic disorder and ten subjects with infrequent panic attacks were assessed during 2 min of voluntary hyperventilation using four measures of physiological arousal (heart rate, upper trapezious EMG, skin conductance, and digital skin temperature). Immediately following hyperventilation, subjects were asked to rate their degree of distress on 13 panic symptoms, derived from DSM-III criteria for panic disorder. Results indicated that frequent panickers had significant overall elevations in trapezious EMG, relative to infrequent panickers, and demonstrated a slight increase in muscle tension following hyperventilation. In contrast, infrequent panickers showed a trend toward greater vasodilation preceding and during hyperventilation, with subsequent vasoconstriction upon resumption of normal breathing. Increases in skin conductance and heart rate were noted for both samples during hyperventilation, as reported in prior research. Symptom distress ratings indicated that the infrequent panickers reported significantly greater distress from dizziness and trembling in response to overbreathing, contrary to prediction. Implications of these findings are discussed in light of current accounts of cognitive and physiological factors in the etiology of panic attacks and panic disorder.This research was supported by Biomedical Research Support Grant #507RR07147, National Institutes of Health.     

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.     

The relationship between illness perceptions and panic in chronic obstructive pulmonary disease

BackgroundElevated levels of anxiety and panic are common in respiratory disease. To date the cognitive-behavioural model of panic has been utilised to help explain and manage panic in respiratory disease. This cross-sectional study investigated the relationship between illness perceptions and panic in chronic obstructive pulmonary disease (COPD) within a self-regulatory framework of adaptation to physical illness.MethodsFifty-nine participants with COPD completed questionnaires measuring illness perceptions, anxiety and depression, frequency and severity of panic attacks and impact of disease on daily life and well-being. The percent forced expiratory volume in the first second (FEV₁%) was used as an objective measure of lung function.ResultsHigh levels of clinical anxiety and depression were reported (35% and 19% respectively). Sixty-three percent of participants reported experiencing a panic attack during the previous year and of these 51% during the previous month. Panic was unrelated to level of disease severity. Specific illness perceptions (beliefs relating to illness identity, timeline, consequences and emotional representations) were important in differentiating between panickers and non-panickers.ConclusionsThe results highlight the importance of assessing illness perceptions within the framework of the self-regulatory model to provide an additional theoretical perspective for investigating and managing panic in chronic respiratory disease.     

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.     

Panic disorder: A product of classical conditioning

Contrary to the common view that all panic attacks have a single etiology, it is shown that a distinction must be made between initial attacks, for which there are many causes, and recurrent attacks (panic disorder) which have a common basis. Most initial panic attacks are attributable to the physiological effects of hyperventilation resulting from severe and prolonged anxiety. It has been claimed that the attacks are due to such symptoms as dyspnea, tachycardia and dizziness being misattributed to deadly illness or incipient insanity. We reject this view on several grounds, and in particular because of a pilot study that showed that such attributions follow the onset of panic. Apart from some biological cases, the common initial panic is an unconditioned response to a bizarre stimulus complex produced by excessive hyperventilation, and panic disorder is the result of contiguous stimuli, especially endogenous stimuli, being conditioned to the elicited anxiety. Treatment accords with principles of conditioning.     

Responses to false physiological feedback in individuals with panic attacks and elevated anxiety sensitivity

Participants with elevated anxiety sensitivity and a history of panic attacks were compared to a low anxiety comparison group with respect to physiological and subjective reactivity to false heart-rate feedback and reactivity to a priming procedure. Whereas accurate heart-rate feedback elicited minimal responses, participants across groups showed significant physiological and subjective responses to false feedback. High risk and low risk participants did not differ in heart-rate responses to false feedback, though panic attack frequency did predict physiological and subjective reactions to false feedback in the high risk group. Self-reported nonspecific anxiety was significantly higher in high risk female participants than in low risk female participants, while males did not different in general subjective anxiety. However, high risk participants reported more panic-specific symptoms during the false feedback task than low risk participants, regardless of the sex of the participant. Therefore, although the experimental paradigm appeared to trigger nonspecific anxiety in high risk female participants, panic attack symptoms in reaction to the task were specific to risk group, not sex, and consistent with hypotheses. Surprisingly, the priming procedure did not influence physiological or subjective responses to false feedback in either group. These results raise additional questions regarding the process and impact of interoception in individuals with panic attacks, and suggest that false perception of internal changes may contribute to risk for panic disorder when exposed to believable cues.     

Anticipation of interoceptive threat in highly anxiety sensitive persons

Anticipatory anxiety plays a major role in the etiology of panic disorder. Although anticipatory anxiety elicited by expectation of interoceptive cues is specifically relevant for panic patients, it has rarely been studied. Using a population analogue in high fear of such interoceptive arousal sensations (highly anxiety sensitive persons) we evaluated a new experimental paradigm to assess anticipatory anxiety during anticipation of interoceptive (somatic sensations evoked by hyperventilation) and exteroceptive (electric shock) threat. Symptom reports, autonomic arousal, and defensive response mobilization (startle eyeblink response) were monitored during threat and matched safe conditions in 26 highly anxiety sensitive persons and 22 controls. The anticipation of exteroceptive threat led to a defensive and autonomic mobilization as indexed by a potentiation of the startle response and an increase in skin conductance level in both experimental groups. During interoceptive threat, however, only highly anxiety sensitive persons but not the controls exhibited a startle response potentiation as well as autonomic activation. The anticipation of a hyperventilation procedure thus seems a valid paradigm to investigate anticipatory anxiety elicited by interoceptive cues in the clinical context.     

Avoidant coping in panic disorder: a yohimbine biological challenge study

Few studies have addressed whether the use of avoidance-oriented coping strategies is related to the development of panic in patients with panic disorder(PD). Self-report, clinician-rated, and physiological data were collected from 42 individuals who participated in a yohimbine biological challenge study, performed under double-blind, placebo-controlled conditions. Participants included 20 healthy controls and 22 currently symptomatic patients who met DSM-IV-TR diagnostic criteria for PD. Consistent with prediction, patients with PD who had higher perceived efficacy of avoidance-oriented strategies in reducing anxiety-related thoughts reported increased severity in panic symptoms during the yohimbine challenge condition as compared to the placebo. Further, patients with PD who had more fear of cognitive dyscontrol, cardiovascular symptoms, and publicly observable anxiety also reported increased severity in panic symptoms during the challenge. Healthy controls who had more fear of cardiovascular symptoms similarly reported increased severity in panic symptoms during the challenge. No effects were found for heart rate response to the challenge agent. These results provide support for the role of avoidance-oriented coping strategies and fear of anxiety-related symptoms as risk and maintenance factors in the development of panic symptoms, particularly within a biological challenge model.     

Factors influencing drinking behavior in alcoholic panickers and non-panickers

Male alcoholics who (a) experienced panic attacks prior to abusing alcohol, (b) experienced panic attacks subsequent to abusing alcohol, and (c) had not experienced panic attacks were compared on three sets of measures: the Panic Attack Questionnaire, the Restrained Drinking Scale, and the Inventory of Drinking Situations. The results showed that two groups of Ss who experienced panic attacks were more likely than non-panickers to use drugs other than alcohol, began drinking at an earlier age, had a greater proportion of parents with panic and alcohol related problems, had higher drinking restraint scores, and drank in more situations. The Ss who experienced panic attacks prior to abusing alcohol were more likely than the other groups to drink in situations similar to those related to agoraphobic fears. It was postulated that alcoholics who experience panic attacks, especially those who experienced panic attacks prior to abusing alcohol may be using alcohol to reduce anxiety or fear related to panic attacks.