Repeated exposure to interoceptive cues: does habituation of fear occur in panic disorder patients? A preliminary report

Physical Activity Prevalence in Caregivers of Children With Different Ages and Its Association With Their Psychological and Physical Health Problems

OBJECTIVES The purpose of the current study was to estimate the prevalence of meeting national physical activity guidelines among caregivers and to examine the association between meeting the guidelines and psychological and physical health problems in caregivers..METHODS 2018 National Health Interview Survey (NHIS) datasets and the national physical activity guidelines (i.e., 150 minutes of moderate-to-vigorous physical activity per week) were used in the current study.RESULTS The prevalence of meeting national physical activity guidelines among caregivers of young children, school-aged children, and adolescents were 46.78%, 48.55%, and 46.54%, respectively. Physically active caregivers of school-aged children showed significantly lower likelihoods of anxiety and obesity compared to physically inactive caregivers of school-aged children. Physically active caregivers of adolescents showed significantly lower likelihoods of type 2 diabetes, hypertension, hyperlipidemia, obesity, neck pain, and back pain compared to physically inactive caregivers of adolescents.CONCLUSIONS As parents often experience some health problems, they should be encouraged to meet the national physical activity guidelines. Health care professionals should promote physical activity behaviors in caregivers by considering caregiver’s health conditions.

Panic attack provocation in panic disorder patients with a computer simulation

BACKGROUND

Computer simulations (CS) and virtual reality exposure are promising techniques for research and treatment of panic disorder with agoraphobia (PDA). The objective of this study was to ascertain whether a given CS was a stimulus capable of producing panic attacks (PAs), anxiety and psychophysiological changes in patients with PDA.

METHODS

Thirty PDA patients and 30 healthy subjects were recruited for this study. Subjects were exposed to a 3-min CS of a situation relevant to agoraphobic patients. Anxiety, panic symptoms, PAs, heart rate, skin conductance and respiration were recorded before, during and after the CS exposure.

RESULTS

The CS effectively induced anxiety, hyperventilation and electrodermal responses in PDA patients but not in healthy subjects. Forty percent of PDA patients had a PA while none of the control subjects had a PA. A subgroup of patients who were less sensitive to the CS than the other subgroup of PDA patients and did not present full-blown PAs still had more panic symptoms, higher anxiety levels and more respiratory irregularities than the controls.

LIMITATIONS

Low immersion and low sense of presence, lack of interaction with the environment.

CONCLUSIONS

Exposure to the CS produced effects similar to in vivo exposure, respiratory and caffeine challenges. Subsequent studies should: make direct comparisons between CS and other challenges for PDA; investigate if CS can be a tool for predicting effects of medication; determine the potential of CS as a desensitization technique for situational PAs.

Two Interventions Decrease Anxiety Sensitivity Among High Anxiety Sensitive Women: Could Physical Exercise Be the Key?

A brief group-based cognitive behavioral therapy (CBT), with running as an interoceptive exposure (IE) component, was effective in reducing anxiety sensitivity (AS) levels in undergraduate women (Watt, Stewart, Lefaivre, & Uman, 2006). This study investigated whether the CBT/IE intervention would result in decreases in AS and emotional distress that would be maintained over 14 weeks. Female undergraduates, high (n = 81) or low (n = 73) in AS, were randomized to 3-day CBT plus forty-two 10-min running IE trials (n = 83) or 3-day health education control (HEC) with interactive discussions and problem solving on exercise, nutrition, and sleep (n = 71). The CBT/IE intervention led to decreases in AS, depression, and stress symptoms for high AS participants, which were maintained at 14 weeks. Unexpectedly, HEC participants experienced similar and lasting decreases in AS, depression, and anxiety symptoms. Furthermore, there were no post-intervention differences between CBT/IE and HEC participants in any of the outcomes. Low AS participants experienced few sustained changes. Clinical implications and the possible role of aerobic exercise in explaining outcomes of both interventions are discussed.

Neural Circuitry of Interoception: New Insights into Anxiety and Obsessive-Compulsive Disorders

Over the past century, much research has investigated how the brain processes signals from the body (interoception) and how this processing may be disturbed in patients with psychiatric disorders. In this paper, I discuss the literature examining the relationship between interoceptive awareness and emotional and cognitive processes, and review the evidence suggesting that anxiety and obsessive-compulsive disorder (OCD) are characterized by abnormal interoception. A network of cortical and subcortical brain regions centered on the insula has repeatedly been implicated in interoception and is abnormal in anxiety and OCD. The investigation of interoception provides a framework for understanding behavioral and neural mechanisms of anxiety and OCD, although additional research is needed to directly link insula functioning to aberrant interoception in these disorders. Future work targeting interoception may be useful for the development of novel treatments.

Experiential, autonomic, and respiratory correlates of CO2 reactivity in individuals with high and low anxiety sensitivity

Psychometric studies indicate that anxiety sensitivity (AS) is a risk factor for anxiety disorders such as panic disorder (PD). To better understand the psychophysiological basis of AS and its relation to clinical anxiety, we examined whether high-AS individuals show similarly elevated reactivity to inhalations of carbon dioxide (CO2) as previously reported for PD and social phobia in this task. Healthy individuals with high and low AS were exposed to eight standardized inhalations of 20% CO2-enriched air, preceded and followed by inhalations of room air. Anxiety and dyspnea, in addition to autonomic and respiratory responses were measured every 15 s. Throughout the task, high AS participants showed a respiratory pattern of faster, shallower breathing and reduced inhalation of CO2 indicative of anticipatory or contextual anxiety. In addition, they showed elevated dyspnea responses to the second set of air inhalations accompanied by elevated heart rate, which could be due to sensitization or conditioning. Respiratory abnormalities seem to be common to high AS individuals and PD patients when considering previous findings with this task. Similarly, sensitization or conditioning of anxious and dyspneic symptoms might be common to high AS and clinical anxiety. Respiratory conditionability deserves greater attention in anxiety disorder research.

Anxiety sensitivity and interoceptive exposure: a transdiagnostic construct and change strategy

Recent findings support the relevance of anxiety sensitivity (AS) and interoceptive exposure (IE) across emotional disorders. This study (a) evaluated levels of AS across different anxiety disorders, (b) examined change in AS over the course of transdiagnostic psychological intervention, and its relationship with outcome, and (c) described the implementation of IE to address AS with patients with different anxiety disorders. Participants (N=54) were patients who received treatment with the Unified Protocol for Transdiagnostic Treatment of Emotional Disorders (UP) in two consecutive treatment trials. Participants completed a measure of AS at pre- and posttreatment, and multiple occasions during treatment. Symptom severity was assessed at pre- and posttreatment, and clinical information related to physical symptoms and IE were collected as part of routine clinical practice. Elevated AS was observed at pretreatment across diagnoses and decreases in AS were observed from pre- to posttreatment. Similar changes occurred across the diagnostic categories, notably coinciding with the introduction of IE. Change in AS was correlated with reduced symptom levels at posttreatment and 6-month follow-up. Patients with different anxiety disorders endorsed similar physical symptoms and practiced similar IE exercises with similar effects. Results provide preliminary support for the usefulness of IE as a treatment strategy across the spectrum of anxiety disorders, and additional support for the transdiagnostic relevance of AS.

Respiratory, autonomic, and experiential responses to repeated inhalations of 20% CO₂ enriched air in panic disorder, social phobia, and healthy controls

Inhalation of carbon dioxide (CO₂) enriched air triggers anxiety in panic disorder (PD) patients, which is often interpreted as a sign of biological vulnerability. However, most studies have not measured respiration in these tasks. We compared patients with PD (n=20) and social phobia (SP, n=19) to healthy controls (n=18) during eight inhalations of 20% CO₂, preceded and followed by two inhalations of room air, while continuously measuring subjective anxiety and dyspnea as well as autonomic and respiratory variables. PD patients showed increased reactivity and delayed recovery during CO₂ inhalations for most measures. Unlike both other groups, the PD group's tidal volume responses did not habituate across CO₂ inhalations. However, PD patients did not differ from SP patients on most other measures, supporting a continuum model of CO₂ sensitivity across anxiety disorders. Both patient groups showed continued reactivity during the last air inhalations, which is unlikely to be due to a biological sensitivity.

Was wirkt in der Kognitiven Verhaltenstherapie der Panikstörung mit Agoraphobie?

Die kognitive Verhaltenstherapie (KVT) hat sich in empirischen Studien als wirksame Behandlungsform von Panikstörungen mit Agoraphobie erwiesen. Zu den zentralen Behandlungskomponenten gehören a) Psychoedukation über Angst und Panik, b) kognitive Interventionen, um die Tendenz zu Missinterpretationen körperlicher Wahrnehmungen zu vermindern, c) interozeptive und in vivo Exposition sowie d) Bewältigungskompetenzen zur Beeinflussung von körperlichen Symptomen, wie beispielsweise Entspannungs- und Atemtechniken. Empirische Befunde zur Effektivität dieser Interventionen werden vorgestellt und abschließend hinsichtlich ihrer Bedeutung im Rahmen einer evidenzbasierten Therapie der Panikstörung mit und ohne Agoraphobie in der Praxis diskutiert.

Sensitization of catastrophic cognition in cognitive-behavioral therapy for panic disorder

BACKGROUND

Cognitive model of panic disorder have proposed that panic attacks result from the catastrophic misinterpretation of certain bodily sensations. Cognitive-Behavioral Therapy (CBT) for panic disorder aims to change these catastrophic cognitions. CBT intervention successfully caused reduction of catastrophic cognitions and symptomatic improvement in the majority of cases. However there are some patients who fail to modify their catastrophic cognitions or rather experience an increase in them during CBT treatment. It is clinically and theoretically important to understand about cognitive sensitization of panic disorder during CBT sessions. The purpose of the present study is 1) to clarify the baseline characteristics of panic patients who would experience sensitization of their catastrophic cognitions through the CBT treatment, and 2) to examine the course of symptomatic changes for them.

METHODS

Of ninety-five outpatients with panic disorder started the group CBT program for treatment of panic disorder, seventy-nine completer were classified as "cognitively sensitized (CS)" or "cognitive responding (CR)" or "no-responder" according to the difference of the Agoraphobic Cognitions Questionnaire score across treatment. We compared the CS and CR patients in terms of their baseline clinical characteristics. Then we assessed the symptomatic and functional changes for both groups.

RESULTS

At the start of the CBT program, despite of the same degree of panic disorder severity, CS scored significantly lower on ACQ score than CR. CS also showed significantly lower score on anticipatory anxiety compared to CR. At the end of treatment CS showed significant improvement in severity of panic disorder, although the degree of improvement was smaller than that for CR. Then CS would progressively reduce their agoraphobic fear and avoidance, and would improve their functional impairment up to three month of follow-up.

CONCLUSION

Panic patients who would experience sensitization of their catastrophic cognitions through the CBT treatment could nonetheless gradually improve. They showed a relatively low level of catastrophic cognition and anticipatory anxiety before starting the CBT program. We might conclude that temporary sensitization of catastrophic cognition may be necessary before improvement especially among those with initially low catastrophic body sensation fears and that we need not be concerned too much with temporary increase in catastrophic cognition in the process of CBT for panic disorder.

Repeated experiences of air hunger and ventilatory behavior in response to hypercapnia in the standardized rebreathing test: effects of anxiety

In this study, we assessed air hunger (AH) and ventilatory responses to repeated CO(2) exposures in healthy women (N=31), scoring high or low for trait anxiety. A standardized rebreathing test, implying a gradually increasing CO(2) stimulus, was administered three times with 15-min intervals. Respiratory behavior and the intensity of AH perception were measured continuously. Across repeated exposures, maximal tolerance for AH habituated and the slope of AH (increase in AH per unit increase in CO(2)) diminished. Also the dynamics of the breathing response changed across trials. The thresholds for AH and tidal volume (V(T)) moved closer to each other, whereas the threshold for the respiratory rate (RR) was generally postponed. In addition, the association between AH and V(T) was stronger than between AH and RR, and the latter association became weaker over trials, particularly in high anxious persons. This suggests that AH perception became increasingly influenced by psychological factors, especially in high anxious persons. The results suggest that habituation of perceived air hunger is depending on a complex interplay between both changes in respiratory behavior and in perceptual-cognitive processes related to trait anxiety.

Recognition of happy facial affect in panic disorder: an fMRI study

BACKGROUND

This study investigated activation of the anterior cingulate cortex (ACC) and amygdala during the presentation of happy facial affect images in patients with panic disorder (PD) as measured by blood oxygen level dependent (BOLD) functional magnetic resonance imaging (fMRI).

METHODS

Eight patients with PD and eight sex-matched controls were recruited for the study. Scanning was performed on a general electric (GE) Signa 1.5T scanner retrofitted with a whole body echo planar coil. Using a quadrature head coil, echo planar images and high-resolution MR images were acquired.

RESULTS

After covarying for age, examination of group differences revealed greater ACC activation bilaterally in patients with PD compared to controls in response to happy faces. However, there were no differences in amygdala activation between the groups. These findings contrasted with regional brain activation in response to neutral faces where there were was also greater bilateral ACC activation in the PD group, but only 44 ACC voxels showed significant increases as opposed to 509 voxels for the happy condition. There were no between group differences in activation in the amygdala.

CONCLUSION

This is the first fMRI study to our knowledge that demonstrates ACC abnormalities in response to happy facial affect recognition in PD.

Verbal, behavioural and physiological assessment of the generalization of exposure-based fear reduction in a spider-anxious population

Clinical fear of spiders was assessed in 39 patients before and after exposure treatment and at a 3-month follow-up. The assessment included behavioral, physiological and self-report measures. Some patients were tested in the treatment context (group Same), while others were tested in a different context (group Different). Both groups demonstrated a significant fear reduction from pre- to post-treatment in all measures, which persisted at the 3-month follow-up. Contrary to our expectations, no clear difference was observed between the groups at any moment. However, a 1-year follow-up test of the self-report measure revealed a return of fear in group Same, but not in group Different. These results show (1) that the effects of exposure treatment persisted over contexts and time in the short term, and (2) that conducting treatment and tests in different contexts enhanced efficiency of exposure treatment in the long term.

Interoceptive hypersensitivity and interoceptive exposure in patients with panic disorder: specificity and effectiveness

BACKGROUND

Interoceptive exposure has been validated as an effective component of cognitive behavioral therapy (CBT) for the treatment of panic disorder but has hitherto received little research attention. We examined the effectiveness of various interoceptive exposure exercises using the Body Sensations Questionnaire (BSQ) (Chambless et al., 1984).

METHODS

We first performed an exploratory principal factor analysis of all the items contained in the BSQ to obtain meaningful dimensions of interoceptive fears. Next, we examined the correlations between each interoceptive exposure task's degree of similarity to panic attacks and each BSQ factor and then examined whether the BSQ factor scores decreased in comparison with the baseline values when the corresponding exposure tasks were successfully completed by the subjects.

RESULTS

The factor analyses revealed four factors, which we named "pseudoneurological fears", "gastrointestinal fears", "cardiorespiratory fears" and "fears of dissociative feelings." Among the nine interoceptive exposure tasks, 'hyperventilation', 'shaking head', 'holding breath' and 'chest breathing' were considered to reproduce pseudoneurological symptoms, 'breathing through a straw' was considered to reproduce gastrointestinal symptoms, and 'spinning' was considered to reproduce both pseudoneurological and dissociative symptoms; none of the interoceptive exercises were found to reproduce cardiorespiratory symptoms. Among each group of patients for whom 'hyperventilation', 'holding breath', 'spinning' or 'chest breathing' was effective, a significant improvement in the BSQ pseudoneurological fears factor scores was observed. On the other hand, no significant difference between the baseline and endpoint values of the BSQ gastrointestinal fears or the BSQ fears of dissociative feelings factor scores were observed among the patients for whom 'spinning' or 'breathing through a straw' was effective.

CONCLUSION

Several interoceptive exposure tasks were particularly effective in reducing pseudoneurological fears. New interoceptive tasks, especially tasks related to cardiorespiratory and dissociative feelings, are needed.

Air hunger and ventilation in response to hypercapnia: Effects of repetition and anxiety

We investigated the effects of anxiety on the intensity of air hunger during gradually increasing levels of CO2 until the end-tidal fractional concentration of CO2 was 7.9% or air hunger was intolerable. Normal high and low (trait) anxious participants (N=23) went through three rebreathing trials (15 min interval). Breathing behaviour was continuously monitored and air hunger was rated every 12 s. The threshold for responding to the increased CO2 was always lower for the subjective rating than for the ventilatory response. Habituation across trials was observed for both the ventilatory response and the air hunger rating regardless of anxiety. However, beyond the threshold, the slope in air hunger ratings decreased across trials in low anxious persons and tended to increase in high anxious persons (interaction P<0.05). No differences occurred in the slopes of the breathing responses. The findings documented uncoupling of the physiological and subjective responses during CO2-induced air hunger.

Noise as a Trigger for Headaches: Relationship Between Exposure and Sensitivity

OBJECTIVE

This study investigated how triggers acquire the capacity to precipitate headaches.

BACKGROUND

Traditional clinical advice is that the best way to prevent headache/migraine is to avoid the triggers. Avoidance of anxiety-eliciting stimuli, however, results in sensitization to the stimuli, so is there a danger that avoidance of migraine/headache triggers results in decreased tolerance for the triggers?

DESIGN

One hundred and fifty subjects, 60 of whom suffered from regular headaches, were randomly assigned to 5 experimental conditions, defined by length of exposure to the headache trigger of noise.

METHODS

Subjects attended a laboratory session divided into 3 phases: preintervention test, intervention (1 of 5 levels of exposure to the trigger), and postintervention test. Response to the intervention was measured in terms of noise tolerance, sensitivity to noise, and nociceptive response to noise.

RESULTS

A curvilinear relationship was found between length of exposure to the trigger and pain response for individuals who do not suffer from regular headaches, that is, short exposure was associated with sensitization and prolonged exposure with desensitization. The relationship for headache patients was less clear.

CONCLUSIONS

The findings are consistent with the proposition that 1 etiological pathway to suffering from frequent headaches is via trying to avoid, or escape from, potential trigger factors. These results suggest that the traditional clinical advice to headache patients, that the best way to prevent migraine/headache is to avoid the triggers, runs the risk of establishing an insidious sensitization process thereby increasing headache frequency.

Central and peripheral chemoreflexes in panic disorder

Klein (Arch Gen Psychiatry, 50, 1993, 306-317) has suggested that panic disorder patients have a false suffocation alarm that may be associated with a lowered threshold for carbon dioxide detection. We compared the thresholds and sensitivities of the central and peripheral chemoreflexes between panic disorder patients and age- and sex-matched healthy volunteers to test this aspect of the hypothesis. We used a modified version of Read's rebreathing technique in 11 panic disorder patients and 10 healthy volunteers to examine the peripheral and central chemoreflex characteristics in these two populations. Subjects were examined during three rebreathing tests: training, hyperoxic (central chemoreflex alone) and hypoxic (combined central and peripheral chemoreflex). Panic symptoms were retrospectively assessed between groups using a DSM-IV derived Panic Symptom Scale. Comparisons of panic disorder patients with agoraphobia and healthy volunteers showed no significant differences in sensitivities or thresholds. Klein's hypothesis is not supported by these data. If a false suffocation alarm exists, its triggering may not be implemented within the respiratory chemoreflexes.

A review of psychological factors/processes affecting anxious responding during voluntary hyperventilation and inhalations of carbon dioxide-enriched air

Despite advances in our understanding of the nature of anxiety-related responding during periods of elevated bodily arousal, it is not necessarily evident by what psychological mechanisms anxiety is produced and maintained. To address this issue, researchers have increasingly employed biological challenge procedures to examine how psychological factors affect anxious responding during elevated bodily arousal. Of the challenging procedures, hyperventilation and inhalations of carbon dioxide-enriched air have been among the most frequently employed, and a relatively large body of literature using these procedures has now accumulated. Unfortunately, existing reviews do not comprehensively examine findings from hyperventilation and inhalations of carbon dioxide studies, and only rarely the methodological issues specific to these studies. To address these issues, we review the voluntary hyperventilation and carbon dioxide-enriched air literature in order to identify the primary methodological issues/limitations of this research and address the extent to which psychological variables influence anxious responding to such challenges. Overall, we conclude challenge research is a promising paradigm to examine the influence of psychological variables in anxious responding, and that such work will likely be enhanced with greater attention to psychological process issues.

Response to repeated CO2 in individuals with elevated anxiety sensitivity: replication with 20% CO2

The present report replicates and extends previous work examining response patterns to repeated presentation of CO2. In previous studies, two distinct response patterns to repeated presentation of 35% CO2 were noted, representing habituation and nonhabituation of anxiety. In this report, 21 participants who had never experienced a panic attack but who reported high levels of anxiety sensitivity were presented with 12 trials of 20% CO2, followed by a trial involving inhalation of room air (to examine dishabituation) and two more trials of 20% CO2. Results indicated that 67% of the sample reported habituation of anxiety. Reductions in anxiety across inhalations were paralleled by changes in tidal volume, perceived panic symptom severity, and feelings of panic. Notable dishabituation was observed in the nonhabituation sample. Results are discussed in the light of basic learning processes underlying the treatment of Panic Disorder (PD).

Response patterns to repeated CO2 inhalation in individuals with high anxiety sensitivity

The present report extends previous work which has documented two distinct response patterns to repeated presentation of interoceptive cues (using CO2 inhalation) in PD patients [Beck, J. G. & Shipherd, J. C. (1997). Repeated exposure to interoceptive cues: does habituation of fear occur in panic disorder patients? Behaviour Research and Therapy, 35, 551-557]. We were interested in determining if these two patterns of fear habituation and sensitization would be noted in panic-naive individuals who reported high levels of Anxiety Sensitivity. A second aspect of this report examined whether attention to bodily sensations versus to neutral material would impact fear habituation and sensitization. Participants included 43 panic-naive individuals who scored at least 1 standard deviation above norms on the Anxiety Sensitivity Index. Results indicated that 37% of the sample reported habituation of fear, 47% reported fear sensitization and 16% demonstrated relatively stable fear levels across 12 inhalations of CO2 during session 1. The attentional manipulation did not exert a pronounced influence on anxiety, panic symptom severity, skin conductance, or heart rate in either Habituators or Sensitizers during session 2. These results are discussed in light of their relevance in understanding fundamental psychopathological processes underlying Panic Disorder.

How does interoceptive exposure for panic disorder work? An uncontrolled case study

To examine the influence of interoceptive exposure (IE) when used alone in the treatment of Panic Disorder (PD), 17 PD patients were presented with six IE sessions, using 35% CO2 as the exposure medium. The data indicate that IE alone is effective in reducing panic, panic-related fears, and general anxiety. However, the positive effects of IE do not appear to extend to agoraphobia, related fears, or depressed mood. Two distinct within-session patterns of fear response to IE were noted, one indicating habituation and the other indicating a lack of fear reduction. Although both patterns were associated with reductions in panic and anxiety following IE, the Habituators appeared to have a more positive outcome, which occurred more rapidly. These data suggest that IE may operate via two different pathways. Implications for understanding fear reduction are discussed, along with directions for future study.