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.     

Anxiety sensitivity and history of panic as predictors of response to hyperventilation

In this study, we examined the effects of anxiety sensitivity on the response to hyperventilation in college students with and without a history of spontaneous panic attacks. Reiss et al.'s (Behav. Res. Ther. 24, 1-8, 1986) Anxiety Sensitivity Index and Norton et al.'s (Behav. Ther. 17, 239-252, 1986) Panic Attack Questionnaire were used to select Ss. Following five min of voluntary hyperventilation, high anxiety sensitivity Ss reported more anxiety and more hyperventilation sensations than did low anxiety sensitivity Ss. A history of panic was only associated with enhanced responding to hyperventilation in Ss with high anxiety sensitivity; low anxiety sensitivity Ss who had experience with panic were no more responsive than low anxiety sensitivity Ss who had never had a panic attack. These findings suggest that high anxiety sensitivity may be a crucial determinant of panic attacks provoked by biological challenges (e.g. hyperventilation, sodium lactate infusion).     

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.     

The role of anxiety sensitivity and lack of emotional approach coping in depressive symptom severity among a non-clinical sample of uncued panickers

Panic attacks and depression frequently co-occur, and the presence of this co-morbidity is often associated with worse outcomes compared with each disorder alone. Despite this, not everyone who experiences panic attacks also suffers from depression, suggesting that individual difference factors may play a role in this co-morbidity. The purpose of this study was to provide a preliminary investigation of two such individual difference factors, examining the role of anxiety sensitivity and lack of emotional approach coping in depressive symptom severity among a non-clinical sample of uncued panickers. A sample of 79 college students reporting the occurrence of uncued panic attacks within the past year completed a series of questionnaires assessing the lower-order factors of anxiety sensitivity, emotional approach coping, panic attack frequency, panic-related disability, panic symptom severity and depressive symptom severity. Participants with more severe depressive symptoms reported greater anxiety sensitivity, panic attack frequency, panic symptom severity, panic-related disability and lack of emotional approach coping. The particular anxiety sensitivity dimension of fear of cognitive dyscontrol and lack of emotional approach coping emerged as the best predictors of depressive symptom severity. Findings are discussed in terms of their implications for the improved understanding of this co-morbidity, as well as its treatment.     

Somatic complaints in anxious children

Although stomachaches and headaches are considered characteristic of children with anxiety disorders, there is converging evidence that a broader range of somatic symptoms may be associated with children's expressions of anxiety. The purpose of this study was to determine the prevalence of somatic complaints in anxious children. The results indicated that children with anxiety disorders endorsed the presence of many different somatic complaints, and that contrary to clinical intuition, stomaches and headaches were not among the most commonly reported symptoms. In addition, the anxious children endorsed significantly more somatic complaints when compared to normal controls. Furthermore, the symptom pattern reported by anxious children indicated the presence of both the somatic and cognitive components usually associated with panic attacks, although none of the children met diagnostic criteria for panic disorder. The results are discussed in terms of the contribution of somatic symptoms to the understanding of anxiety disorders in children.     

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Panic attacks and depression frequently co‐occur, and the presence of this co‐morbidity is often associated with worse outcomes compared with each disorder alone. Despite this, not everyone who experiences panic attacks also suffers from depression, suggesting that individual difference factors may play a role in this co‐morbidity. The purpose of this study was to provide a preliminary investigation of two such individual difference factors, examining the role of anxiety sensitivity and lack of emotional approach coping in depressive symptom severity among a non‐clinical sample of uncued panickers. A sample of 79 college students reporting the occurrence of uncued panic attacks within the past year completed a series of questionnaires assessing the lower‐order factors of anxiety sensitivity, emotional approach coping, panic attack frequency, panic‐related disability, panic symptom severity and depressive symptom severity. Participants with more severe depressive symptoms reported greater anxiety sensitivity, panic attack frequency, panic symptom severity, panic‐related disability and lack of emotional approach coping. The particular anxiety sensitivity dimension of fear of cognitive dyscontrol and lack of emotional approach coping emerged as the best predictors of depressive symptom severity. Findings are discussed in terms of their implications for the improved understanding of this co‐morbidity, as well as its treatment.     

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.     

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 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.     

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.     

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.     

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.     

Prospective evaluation of the etiology of anxiety sensitivity: test of a scar model

A large body of research has suggested that anxiety sensitivity (AS) acts as a specific vulnerability factor in the development of anxiety pathology. More recently, attention has turned to the etiology of AS per se. The present study represents a specific test of a Scar model of AS. A Scar model posits that the experience of distress will affect the vulnerability factor. We were specifically interested in evaluating the effects of a specific stressor (spontaneous panic) as well as general distress on changes in AS over time. A large nonclinical sample of young adults (N = 1296) was prospectively followed over a five week highly stressful period of time (i.e. military basic training). Findings were consistent with the Scar model and suggested that the specific stressor of experiencing a panic attack as well as general stressors creating significant anxiety symptoms uniquely contributed to increased levels of AS (regardless of prior history of panic). Moreover, the experience of spontaneous panic in the context of generally low levels of distress (both anxiety and depression) appeared to be particularly pernicious in terms of resulting in greater increases in AS. In sum, anxiety-related stressors appear to have the potential to 'scar' individuals in regard to this cognitive vulnerability factor.     

Generalized anxiety and panic disorders: Response to Cox, Cohen, Direnfeld, and Swinson (1996)

Contrary to the contention of Cox, Cohen, Direnfeld and Swinson (1996, Behaviour Research and Therapy, 34, 949–954) that the Beck Anxiety Inventory (BAI; Beck & Steer, 1993, Manual for the Beck Anxiety Inventory) measures primarily symptoms associated with panic attacks rather than anxiety in general, we propose that the higher level of anxiety found in patients with panic disorders not only is not an artifact of the BAI's symptom content, but patients with panic disorders truly have more anxiety than patients with other types of anxiety disorders. Furthermore, the BAI contains symptoms present in other anxiety disorders, besides panic disorder, and specifically includes 11 symptoms of generalized anxiety disorder (GAD). The BAI and revised Hamilton Anxiety Rating Scale (HARS-R; Riskind, Beck, Brown & Steer, 1987, Journal of Nervous and Mental Disease, 175, 474–479) scores of 274 (69%) outpatients with panic disorders and 123 (31%) outpatients with GAD were found to differentiate these two diagnostic groups equally and significantly. The panic disorder outpatients had higher scores on both the BAI and the HARS-R than did the GAD patients. Thus, Cox et al.'s (1996) speculation about the BAI's yielding spuriously high levels of anxiety in patients with panic disorders revives an important issue relevant to the relation of panic disorder to GAD.     

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.     

The hyperventilation provocation test in panic disorder.

Forty-eight patients with DSM-III-R Panic Disorder underwent a hyperventilation provocation Test (HVPT). Twenty-four patients rated the symptoms induced during the HVPT as similar to those occurring during panic attacks in daily life. Contrary to the classical hyperventilation model of panic, no differences were found in respiratory physiology between recognizers and non-recognizers before and during voluntary hyperventilation. Moreover, recognizers and non-recognizers reported comparable levels of panic and hyperventilation symptoms and state anxiety during panic attacks in daily life. Ten of the recognizers also had a panic attack during the HVPT, independent of any differential CO2 alterations. Compared to non-panickers, panickers obtained higher scores for agoraphobia and depression. On the basis of these results, it is concluded that recognizers or panickers do not show a tendency towards hyperventilation, but that reports of severe panic and hyperventilation symptoms are more closely related to the level of anxiety. These results are more consistent with the cognitive model of panic, which emphasizes the patient's tendency to interpret somatic symptoms catastrophically.     

Associations between emotional avoidance,anxiety sensitivity,and reactions to an observational fear challenge procedure

Research has shown that emotional avoidance and anxiety sensitivity are associated with more self-reported fear and distress in response to laboratory fear challenge procedures. The present study aimed to expand upon this work and examined how emotional avoidance and anxiety sensitivity are related to emotional and physiological responses to an observational fear challenge procedure. To accomplish this aim, a carefully screened, non-clinical sample (N = 43) was administered the Acceptance and Action Questionnaire (AAQ), a measure of emotional avoidance, and the Anxiety Sensitivity Index (ASI). Participants then engaged in an observational fear challenge paradigm. During the fear challenge, participants watched mock panic attacks while emotional (e.g., fear and panic) and skin conductance levels were assessed. Consistent with expectation, emotional avoidance and anxiety sensitivity were positively associated with more self-reported fear and more severe panic symptoms to the challenge procedure. However, anxiety sensitivity was more highly associated with self-reported fear and panic symptoms in response to the challenge procedure than emotional avoidance. Emotional avoidance and anxiety sensitivity were not associated with levels of physiological arousal to the observational fear challenge procedure. Discussion focuses on the interplay between emotional avoidance, anxiety sensitivity, and the development of vicarious fear responses and how these constructs may contribute to the pathogenesis of anxiety disorders.     

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.     

Sensations, cognitions and the perception of cues associated with expected and unexpected panic attacks

Panic attacks may be perceived by patients as either cued or uncued (spontaneous) and either expected or unexpected. The purpose of the present study was to examine the prevalence and characteristics of these types of panic. Twenty-six panic disorder patients with mild avoidance and 18 with moderate or severe avoidance were instructed to complete a questionnaire during or immediately following each of three consecutive naturally occurring panic attacks they experienced. They were asked to rate the extent to which they expected the panic attack to occur, whether they felt it was associated with an external panic "cue" (e.g. a shopping mall), whether they would expect to panic again in similar circumstances, their mood, present level of life stress, and fear and severity of their body sensations and disturbing cognitions. Results indicated that from a sample of 92 questionnaires, each representing a separate panic, nearly 70% of panic attacks were rated as cued-expected and only one panic was rated as uncued-expected. The other two categories each comprised about 15% of all panic attacks. There were few reported differences in body sensations and cognitions reported as a function of type of panic and no differences with regard to extent of agoraphobic avoidance. Expected panic was associated with a higher expectation of future panic in similar circumstances.