Airway response to emotion- and disease-specific films in asthma, blood phobia, and health

Biofeedback Training to Increase P co2 in Asthma With Elevated Anxiety: A One-Stop Treatment of Both Conditions?

OBJECTIVE

Anxiety is highly prevalent in individuals with asthma. Asthma symptoms and medication can exacerbate anxiety, and vice versa. Unfortunately, treatments of comorbid anxiety and asthma are largely lacking. A problematic feature common to both conditions is hyperventilation. It adversely affects lung function and symptoms in asthma and anxiety. We examined whether a treatment to reduce hyperventilation, shown to improve asthma symptoms, also improves anxiety in asthma patients with high anxiety.

METHOD

One hundred twenty English- or Spanish-speaking adult patients with asthma were randomly assigned to either Capnometry-Assisted Respiratory Training (CART) to raise P co2 or feedback to slow respiratory rate (SLOW). Although anxiety was not an inclusion criterion, 21.7% met clinically relevant anxiety levels on the Hospital Anxiety and Depression Scale (HADS). Anxiety (HADS-A) and depression (HADS-D) scales, anxiety sensitivity (Anxiety Sensitivity Index [ASI]), and negative affect (Negative Affect Scale of the Positive Affect Negative Affect Schedule) were assessed at baseline, posttreatment, 1-month follow-up, and 6-month follow-up.

RESULTS

In this secondary analysis, asthma patients with high baseline anxiety showed greater reductions in ASI and PANAS-N in CART than in SLOW ( p values ≤ .005, Cohen d values ≥ 0.58). Furthermore, at 6-month follow-up, these patients also had lower ASI, PANAS-N, and HADS-D in CART than in SLOW ( p values ≤ .012, Cohen d values ≥ 0.54). Patients with low baseline anxiety did not have differential outcomes in CART than in SLOW.

CONCLUSIONS

For asthma patients with high anxiety, our brief training designed to raise P co2 resulted in significant and sustained reductions in anxiety sensitivity and negative affect compared with slow-breathing training. The findings lend support for P co2 as a potential physiological target for anxiety reduction in asthma.

TRIAL REGISTRATION

Clinicaltrials.gov Identifier: NCT00975273 .

Asthma's effect on brain connectivity and cognitive decline

Objective

To investigate the changes in dynamic voxel mirror homotopy connection (dVMHC) between cerebral hemispheres in patients with asthma.

Methods

Our study was designed using a case-control method. A total of 31 subjects with BA and 31 healthy subjects with matching basic information were examined using rsfMRI. We also calculated and obtained the dVMHC value between the cerebral cortexes.

Results

Compared with the normal control group, the dVMHC of the lingual gyrus (Ling) and the calcarine sulcus (CAL), which represented the visual network (VN), increased significantly in the asthma group, while the dVMHC of the medial superior frontal gyrus (MSFG), the anterior/middle/posterior cingulate gyrus (A/M/PCG), and the supplementary motor area (SMA) of the sensorimotor network decreased significantly in the asthma group.

Conclusion

This study showed that the ability of emotion regulation and the efficiency of visual and cognitive information processing in patients with BA was lower than in those in the HC group. The dVMHC analysis can be used to sensitively evaluate oxygen saturation, visual function changes, and attention bias caused by emotional disorders in patients with asthma, as well as to predict airway hyperresponsiveness, inflammatory progression, and dyspnea.

Subcortical gray matter volumes in asthma: associations with asthma duration, control, and anxiety

Asthma as a chronic inflammatory disease can be expected to affect central nervous system structures but little is known about subcortical structures in asthma and their potential association with illness-specific outcomes and anxiety. A total of 40 young adults (20 with asthma and 20 gender- and age-matched controls) underwent high-resolution T1-weighted MRI scan, viewed short distressing film clips, and filled in questionnaires about anxious and depressed mood, as well as asthma history, control, and catastrophizing thoughts about asthma, for those with asthma. The structural scans were processed in FSL's FIRST program to delineate subcortical structures of interest: amygdala, hippocampus, putamen, pallidum, caudate nucleus, nucleus accumbens, and thalamus. Findings showed no general reduction in subcortical gray matter volumes in asthma compared to controls. Asthma duration, asthma control, and catastrophizing of asthma and asthma attacks were negatively associated with volumes of putamen and pallidum, and to a weaker extent thalamus and amygdala, while controlling for gender, age, and corticosteroid inhaler use. In addition, stronger anxiety in response to distressing films was associated with lower volume of the pallidum, whereas general anxious and depressed mood was unrelated to subcortical structures. Thus, although there are no subcortical structural differences between young adults with asthma and healthy controls, longer asthma history, suboptimal management, and illness-related anxiety are reflected in lower gray matter volumes of subcortical structures, further emphasizing the importance of maintaining optimal asthma control.

Anxiety Disorders and Medical Comorbidity: Treatment Implications

Anxiety disorders are debilitating psychological disorders characterized by a wide range of cognitive and somatic symptoms. Anxiety sufferers have a higher lifetime prevalence of various medical problems. Chronic medical conditions furthermore increase the likelihood of psychiatric disorders and overall dysfunction. Lifetime rates of cardiovascular, respiratory, gastrointestinal, and other medical problems are disproportionately high in anxiety and panic/fear sufferers. The heightened comorbidity is not surprising as many symptoms of anxiety and panic/fear mimic symptoms of medical conditions. Panic disorder specifically is strongly linked to medical conditions due to its salient somatic symptoms, such as dyspnea, dizziness, numbness, chest pain, and heart palpitations, all of which can signal danger and deterioration for chronic disease sufferers. This chapter identifies shared correlates of medical illness and anxiety disorders and evidence for misinterpretation of symptoms as medically relevant and offers an analysis of implications for treatment of both types of conditions. We will concentrate on medical conditions with high associations for anxiety and panic by aspects of symptomatology, specifically neurological disorders (fibromyalgia, epilepsy, cerebral palsy), diabetes, gastrointestinal illness (irritable bowel syndrome, gastroesophageal reflux disease), and cardiovascular and respiratory illnesses (asthma).

Central nervous system signatures of affect in asthma: associations with emotion-induced bronchoconstriction, airway inflammation, and asthma control

The effects of asthma on affect have been noted for some time, but little is known about associated brain processes. We therefore examined whether emotion-induced bronchoconstriction, airway inflammation, and asthma control are related to specific patterns of brain activity during processing negative affective stimuli. Fifteen adults with asthma viewed alternating blocks of distressing film clips (negative condition), affectively neutral film clips (neutral condition), and a crosshair image (baseline condition) while undergoing blood oxygenation level-dependent (BOLD) functional MRI (fMRI). Block-design fMRI analysis evaluated the BOLD response to "negative-baseline" and "neutral-baseline" contrasts. Airway response to these film clips was also assessed with impulse oscillometry in a separate session. Measures of airway inflammation [fractional exhaled nitric oxide (FE_NO)] and asthma control [Asthma Control Questionnaire (ACQ)] were additionally obtained. A whole brain voxel-based regression analysis of contrast maps was performed against respiratory resistance increase during negative and neutral films, FE_NO, and ACQ. Peak airway obstruction to negative affective stimulation was associated with stronger activation of the anterior and middle cingulate gyrus, including the dorsal anterior cingulate cortex (dACC). Stronger airway inflammation and lower asthma control were associated with reduced activation to negative stimuli in the superior frontal gyrus, middle cingulate gyrus, and supplementary motor area. Activation of the dACC in negative-affect-induced airway obstruction could be part of an integrated defensive response to critical environmental change. In addition, reduced frontal and limbic activation during processing of negative affect may reflect consequences of pathophysiological processes for CNS functioning. NEW & NOTEWORTHY This functional magnetic resonance imaging study shows, for the first time, that the degree of airway constriction due to negative affective stimuli in asthma is associated with stronger response to these stimuli in the dorsal anterior and middle cingulate cortex. Asthma patients with stronger airway inflammation and reduced asthma control also show reduced activation in a number of cortical and subcortical areas relevant for affective processing and breathing control.

Ultra-brief behavioral skills trainings for blood injection injury phobia

BACKGROUND

Blood injection injury (BII) phobia is common, with debilitating consequences to the health and well being of many of its sufferers. BII phobia presents with a unique fear response that can involve drops in blood pressure and ultimately fainting. The aim of this study was to provide proof of concept for a line of brief, easy to implement, video-based interventions for reducing phobic avoidance and fears in BII sufferers. One of the interventions was a novel Hypoventilation Respiratory Training (HRT) aimed at reducing the exaggerated ventilation response (hyperventilation) seen in BII phobia. The response has been linked to cerebral vasoconstriction and fainting symptoms.

METHOD

Sixty BII patients were randomly assigned to one of three 12-min video-guided trainings: Symptom-Associated Tension (SAT) training, Relaxation Skills Training (RST), or HRT. Experiential and cardiorespiratory activity to phobic stimuli was assessed before and after training.

RESULTS

Both SAT and HRT resulted in overall greater reductions of phobic fears and symptoms than RST. SAT significantly increased heart rate during exposure, and HRT led to significantly reduced ventilation, increases in PCO₂ , and elevated blood pressure throughout exposure and recovery. Treatment expectancy was rated equally high across conditions, whereas credibility ratings were highest for HRT.

CONCLUSIONS

Brief, video-based instructions in muscle tension and normocapnic breathing are effective in reducing BII symptom severity and require minimal time and expertise. HRT may be particularly helpful in reducing fainting caused by cerebral vasoconstriction.

Effects of acute psychological stress induced in laboratory on physiological responses in asthma populations: A systematic review

BACKGROUND

Psychological stress has long been suspected to have a deleterious effect on asthma, with acute psychological stress being associated with physiological responses in asthma patients.

OBJECTIVES

The purpose of this systematic review was to provide a narrative synthesis of the impact of acute laboratory psychological stress on physiological responses among asthma patients.

METHODS

An extensive search was conducted by two independent authors using Pubmed, PsycINFO, PsyArticles and the Cochrane Library electronic databases (up to September 2016). English and French articles which assessed physiological responses during or post-stress and compare them to baseline or pre-stress values were included.

RESULTS

Thirty-two studies met the inclusion criteria. Studies indicated that exposure to active stressors (e.g., arithmetic tasks) was associated with an increase in sympathetic nervous system (SNS) responses, cortisol, and inflammatory responses, but had little effect on the caliber of the bronchi. Exposure to passive stressors (e.g., watching stressful movies or pictures) was also associated with an increase in SNS responses and with mild bronchoconstriction. However, a paucity of data for passive stressors limited conclusions on other measures.

CONCLUSIONS

In patients with asthma, both active and passive stressors seem to be associated with an increased activation of the SNS. Passive stressors seem to have a more immediate, deleterious impact on the airways than active stressors, but the latter may be associated with delayed inflammatory driven an asthma exacerbation. Further studies are needed to understand the impact of acute stressors on the physiological mechanisms associated with asthma, particularly HPA and immune markers. Systematic review registration number: CRD42015026431.

Airway reactivity in response to repeated emotional film clip presentation in asthma

Emotional stimuli elicit airway constriction in individuals with asthma and in healthy individuals, but little is known about effects of repeated stimulation. We therefore explored the effect of repeated emotion induction on respiratory resistance (R_rs) using unpleasant, high-arousal surgery films and investigated effects of respiration and emotional reactivity. Twenty-six participants (13 with asthma) watched a series of 12 short, 45-s surgery films followed by 2-min recovery periods. R_rs assessed with impulse oscillometry was significantly elevated during films in both groups compared to baseline and recovered quickly after that. No habituation of airway responses occurred. R_rs was higher in participants who felt more aroused and less in control when watching the films. Changes in R_rs remained significant when controlling for changes in respiration or emotional experience. Thus, although unpleasant stimuli lead to elevated R_rs, airway obstruction is not exacerbated with repeated stimulation due to a fast return to baseline after stimulation.

Can bronchial asthma with an highly prevalent airway (and systemic) vagal tone be considered an independent asthma phenotype? Possible role of anticholinergics

Recently, we studied occurrence and role of non-respiratory symptoms (n-RSs) before a worsening of asthma symptoms. Some n-RSs such as anxiety, reflux, heartburn, abdominal pain, which appeared within 3 h before the onset of an asthma attack, are the likely result of an imbalance between sympathetic/parasympathetic systems with an increase in cholinergic tone. Therefore, it is likely that some of these n-RSs induced by the increased cholinergic tone might be present related with specific parasympathetic-associated respiratory symptoms such as those elicited by airway narrowing. It is likely that, at least in some categories of asthmatics, an increased cholinergic tone, rather than other well-known factors, might play a prevalent role in triggering bronchospasm. If this is the case, it is possible to speculate that the use of anticholinergic agents (mainly those with long-acting activity) in patients suffering from asthma should be more beneficial in individuals characterized by a higher degree of cholinergic tone that, consequently might be the ideal target for the use of long-acting anticholinergics and, possibly, represent a novel asthma phenotype. The presence of parasympathetic-associated n-RSs might help the physician to identify this type of patients, although this might be followed by a more detailed assessment.

Psychosocial factors and behavioral medicine interventions in asthma

OBJECTIVE

This review examines the evidence for psychosocial influences in asthma and behavioral medicine approaches to its treatment.

METHOD

We conducted a systematic review of the literature on psychosocial influences and the evidence for behavioral interventions in asthma with a focus on research in the past 10 years and clinical trials. Additional attention was directed at promising new developments in the field.

RESULTS

Psychosocial factors can influence the pathogenesis and pathophysiology of asthma, either directly through autonomic, endocrine, immunological, and central nervous system mechanisms or indirectly through lifestyle factors, health behaviors, illness cognitions, and disease management, including medication adherence and trigger avoidance. The recent decade has witnessed surging interest in behavioral interventions that target the various pathways of influence. Among these, self-management training, breathing training, and exercise or physical activation programs have proved particularly useful, whereas other essential or promising interventions, such as smoking cessation, dietary programs, perception and biofeedback training, and suggestive or expressive psychotherapy, require further, more rigorous evaluation. Given the high comorbidity with anxiety and mood disorders, further evaluation of illness-specific cognitive behavior therapy is of particular importance. Progress has also been made in devising community-based and culturally tailored intervention programs.

CONCLUSION

In concert with an essential medication treatment, behavioral medicine treatment of asthma is moving closer toward an integrated biopsychosocial approach to disease management.

Airway responsiveness to psychological processes in asthma and health

Psychosocial factors have been found to impact airway pathophysiology in respiratory disease with considerable consistency. Influences on airway mechanics have been studied particularly well. The goal of this article is to review the literature on airway responses to psychological stimulation, discuss potential pathways of influence, and present a well-established emotion-induction paradigm to study airway obstruction elicited by unpleasant stimuli. Observational studies have found systematic associations between lung function and daily mood changes. The laboratory-based paradigm of bronchoconstrictive suggestion has been used successfully to elicit airway obstruction in a substantial proportion of asthmatic individuals. Other studies have demonstrated modulation of airway responses to standard airway challenges with exercise, allergens, or pharmacological agents by psychological factors. Standardized emotion-induction techniques have consistently shown airway constriction during unpleasant stimulation, with surgery, blood, and injury stimuli being particularly powerful. Findings with various forms of stress induction have been more mixed. A number of methodological factors may account for variability across studies, such as choice of measurement technique, temporal association between stimulation and measurement, and the specific quality and intensity of the stimulus material, in particular the extent of implied action-orientation. Research has also begun to elucidate physiological processes associated with psychologically induced airway responses, with vagal excitation and ventilatory influences being the most likely candidate pathways, whereas the role of specific central nervous system pathways and inflammatory processes has been less studied. The technique of emotion-induction using films has the potential to become a standardized challenge paradigm for the further exploration of airway hyperresponsiveness mediated by central nervous system processes.

Defensive mobilization in specific phobia: fear specificity, negative affectivity, and diagnostic prominence

BACKGROUND

Understanding of exaggerated responsivity in specific phobia-its physiology and neural mediators-has advanced considerably. However, despite strong phenotypic evidence that prominence of specific phobia relative to co-occurring conditions (i.e., principal versus nonprincipal disorder) is associated with dramatic differences in subjective distress, there is yet no consideration of such comorbidity issues on objective defensive reactivity.

METHODS

A community sample of specific phobia (n = 74 principal; n = 86 nonprincipal) and control (n = 76) participants imagined threatening and neutral events while acoustic startle probes were presented and eyeblinks (orbicularis occuli) recorded. Changes in heart rate, skin conductance level, and facial expressivity were also measured.

RESULTS

Principal specific phobia patients far exceeded control participants in startle reflex and autonomic reactivity during idiographic fear imagery. Distinguishing between single and multiple phobias within principal phobia and comparing these with nonprincipal phobia revealed a continuum of decreasing defensive mobilization: single patients were strongly reactive, multiple patients were intermediate, and nonprincipal patients were attenuated-the inverse of measures of pervasive anxiety and dysphoria (i.e., negative affectivity). Further, as more disorders supplanted specific phobia from principal disorder, overall defensive mobilization was systematically more impaired.

CONCLUSIONS

The exaggerated responsivity characteristic of specific phobia is limited to those patients for whom circumscribed fear is the most impairing condition and coincident with little additional affective psychopathology. As specific phobia is superseded in severity by broad and chronic negative affectivity, defensive reactivity progressively diminishes. Focal fears may still be clinically significant but not reflected in objective defensive mobilization.

Airway constriction in asthma during sustained emotional stimulation with films

BACKGROUND

Individuals with asthma have been shown to respond to unpleasant stimuli with bronchoconstriction, but little is known about the time course of responding during sustained emotional stimulation and whether it varies with patients' experience.

OBJECTIVE

To examine the time course of oscillatory resistance (R(os)) during emotionally evocative films in 15 asthma patients and 14 healthy controls.

METHODS

Participants viewed unpleasant, surgery, and neutral films, each ranging 3-5min in duration. R(os) and the respiratory pattern (respiration rate, tidal volume, minute ventilation) were monitored continuously. Following each film, participants rated their affective response and symptoms. The time course of R(os) during films was explored using multilevel modeling.

RESULTS

Compared to neutral film sequences, unpleasant films (including those with surgery scenes) elicited a uniform pattern of initial increases in R(os) with peaks within the first 1-2min, followed by a gradual decline. Increases were more pronounced in asthma and during surgery films. Including additional respiratory parameters as time-varying covariates did not affect the temporal course of R(os) change. The rate of decline in R(os) (after the initial increase) was less in participants who experienced greater arousal and in patients who reported more shortness of breath. Patients more susceptible to psychological triggers in daily life showed slower rates of decline in R(os).

CONCLUSION

The temporal course of bronchoconstriction to unpleasant stimulation is highly uniform in asthma, with strong constriction in early stages of stimulation. More sustained constriction in emotion-induced asthma could be a risk factor for developing asthma exacerbation in daily life.

Stress-induced respiratory pattern changes in asthma

OBJECTIVES

To build upon prior research on stress-related breathing pattern changes in asthma. Previous research has considered a limited set of respiratory parameters and has remained equivocal. Emotions and stress are known to change the respiratory pattern. In asthma, certain breathing patterns have adverse effects on the airways and lead to symptom exacerbation.

METHODS

We studied respiration during resting conditions and an acute psychosocial stressor (a free speech and mental arithmetic task) in participants with asthma (n = 20) and healthy controls (n = 19). The respiratory pattern was recorded with respiratory inductance plethysmography. Partial pressure of end-tidal carbon dioxide (PCO(2)) was measured with capnometry before and after stress.

RESULTS

The overall minute ventilation was higher in asthma (mean [standard deviation] = 9.0 [4.0] L versus 6.8 [4.1] L, p < .05), but levels of the PCO(2) were comparable (34.6 [3.5] mm Hg versus 35.0 [3.7] mm Hg, p = .667) to healthy controls during prestress and poststress phases. Participants with asthma also showed a significant lengthening of inspiration, expiration, and the total respiratory cycle during stress compared with healthy controls (p < .05). During stress tasks, all participants showed marked increases in tidal volume, inspiratory flow, minute ventilation, tidal volume instability, ribcage contribution to tidal volume, and ribcage-abdominal asynchrony. A significant increase in tidal volume instability and a tendency toward lengthening of expiration and the total respiratory cycle were observed in quiet-sitting periods at prestress to poststress in asthma.

CONCLUSIONS

Expiratory lengthening and variable tidal volumes are characteristic for individuals with asthma during psychosocial stress. The function and possible association of these changes with symptom exacerbations require further study.

The psychophysiology of blood-injection-injury phobia: looking beyond the diphasic response paradigm

Blood-injection-injury (BII) phobia is an anxiety disorder that may be accompanied by vasovagal fainting during confrontation with the feared stimuli. The underlying pattern of autonomic regulation has been characterized as a diphasic response, with initial increases in heart rate and blood pressure that are typical of a fight-flight response, and subsequent drops in blood pressure and/or heart rate that may precipitate vasovagal fainting. Tensing skeletal muscles of the arms, legs, and trunk (applied tension) has been proposed as a technique to cope with this dysregulation. This review critically examines the empirical basis for the diphasic response and its treatment by applied tension in BII phobia. An alternative perspective on the psychophysiology of BII phobia and vasovagal fainting is offered by focusing on hypocapnia that leads to cerebral blood flow reductions, a perspective supported by research on neurocardiogenic and orthostatically-induced syncope. The evidence may indicate a role for respiration-focused coping techniques in BII phobia.