Airway response to emotional stimuli in asthma: the role of the cholinergic pathway

fMRI BOLD responses to film stimuli and their association with exhaled nitric oxide in asthma and health

Little is known about central nervous system (CNS) responses to emotional stimuli in asthma. Nitric oxide in exhaled breath (FENO) is elevated in asthma due to allergic immune processes, but endogenous nitric oxide is also known to modulate CNS activity. We measured fMRI blood oxygen-dependent (BOLD) brain activation to negative (blood-injection-injury themes) and neutral films in 31 participants (15 with asthma). Regions-of-interest analysis was performed on key areas relevant to central adaptive control, threat processing, or salience networks, with dorsolateral prefrontal cortex (PFC), anterior insula, dorsal anterior cingulate cortex (dACC), amygdala, ventral striatum, ventral tegmentum, and periaqueductal gray, as well as top-down modulation of emotion, with ventrolateral and ventromedial PFC. Both groups showed less BOLD deactivation from fixation cross-baseline in the left anterior insula and bilateral ventromedial PFC for negative than neutral films, and for an additional number of areas, including the fusiform gyrus, for film versus recovery phases. Less deactivation during films followed by less recovery from deactivation was found in asthma compared to healthy controls. Changes in PCO2 did not explain these findings. FENO was positively related to BOLD activation in general, but more pronounced in healthy controls and more likely in neutral film processing. Thus, asthma is associated with altered processing of film stimuli across brain regions not limited to central adaptive control, threat processing, or salience networks. Higher levels of NO appear to facilitate CNS activity, but only in healthy controls, possibly due to allergy's masking effects on FENO.

A Comprehensive Review of the Intersection Between Asthma and Depression

Objective To emphasize the necessity for increased research in this field, incorporating depression into the preventative, diagnostic, and therapeutic considerations for asthma. Additionally, we seek to highlight upcoming advancements that can be applied to simultaneously address these comorbidities, ultimately improving the overall well-being and quality of life for individuals coping with these conditions.Methods A rigorous search in PubMed using the MeSH terms "asthma" and "depression" was performed, and papers were screened by the authors in view of their eligibility to contribute to the study.Results There exists a correlation between these two conditions, with specific biological mechanisms and genetic factors playing a crucial role in their concurrent occurrence. In this review, we present preclinical and clinical research data, shed light on the possible mechanisms contributing to the co-occurrence of symptoms associated with both asthma and depression, and explore the intricate relationship between both conditions.Conclusion The evidence presented here supports the existence of a correlation between asthma and depression. By acknowledging these shared biological mechanisms, genetic factors, and epidemiological trends, we can formulate more efficacious strategies for addressing the dual impact of asthma and depression.

An application of the Biobehavioral Family Model: Examining the impact of maternal depression on child asthma mediated by insecure attachment and child depression

OBJECTIVE

Child asthma disparities are prevalent in socio-economically stressed single-parent families. Stress impacts childhood asthma mediated by immune and autonomic pathways, but specific family stress pathways are not well established. This study tests the hypothesis, derived from a version of the Biobehavioral Family Model, that single parent maternal depression impacts child asthma mediated by insecure attachment and child depression.

METHODS

In a cross-sectional study, children with asthma (age 7-17 years old) from a socio-economically disadvantaged population and their single parent mothers (N = 202) were assessed for depression and attachment security. Child asthma disease activity was assessed by symptom report and lung function tests. Structural equation modeling (SEM) was used to test a model in which caregiver depression impacts child asthma disease activity mediated by insecure attachment and child depression.

RESULTS

SEM results indicated that maternal depression statistically predicted child depression (β = 0.21, p < 0.01) and insecure mother-child attachment (β = 0.17, p < 0.05). In addition, insecure attachment statistically predicted child depression (β = 0.50, p < 0.001). Child depression mediated the adverse effects of maternal depression and insecure attachment on child asthma disease activity (β = 0.43, p < 0.01). There was no direct effect of insecure attachment on child asthma.

CONCLUSION

In single-parent families, maternal depression may impact child asthma disease activity, mediated serially by insecure attachment and child depression. Longitudinal and/or intervention studies are needed to establish a causal effect. These findings suggest that caregiver depression and parent-child relationships may be important targets for family intervention. These interventions may help improve child asthma outcomes and reduce health disparities.

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.

Functional abdominal pain disorders and asthma: two disorders, but similar pathophysiology?

INTRODUCTION

Functional abdominal pain disorders (FAPDs) and asthma are common ailments affecting both children and adults worldwide. Multiple studies have demonstrated an association between these two disorders. However, the exact reason for this observed association is not apparent.

AREAS COVERED

The current review has explored available literature and outlined multiple underlying pathophysiological mechanisms, common to both asthma and FAPDs, as possible reasons for this association.

EXPERT OPINION

Smooth muscle dysfunction, hypersensitivity and hyper-responsiveness, mucosal inflammation, and barrier dysfunction involving gastrointestinal and respiratory tracts are the main underlying pathophysiological mechanisms described for the generation of symptoms in FAPDs and asthma. In addition, alterations in neuroendocrine regulatory functions, immunological dysfunction, and microbial dysbiosis have been described in both disorders. We believe that the pathophysiological processes that were explored in this article would be able to expand the mechanisms of the association. The in-depth knowledge is needed to be converted to therapeutic and preventive strategies to improve the quality of care of children suffering from FAPDs and asthma.

Emergency department visits and hospitalisations for asthma, COPD and respiratory tract infections: what is the role of respiratory viruses, and return to school in September, January and March?

Background

Asthma exacerbations increase in September coinciding with children returning to school. The aim of this study was to investigate whether this occurs 1) for COPD and respiratory tract infections (RTIs); 2) after school resumes in January and March; and 3) identify which viruses may be responsible.

Methods

Emergency department (ED) visits and admissions for asthma, COPD and RTIs and the prevalence of viruses in Ontario, Canada were analysed daily between 2003 and 2013. ED visits and admissions were provided by the Canadian Institute for Health Information. Viral prevalence was obtained from the Centre for Immunisation and Respiratory Infectious Diseases.

Results

ED visits and admissions rates demonstrated a biphasic pattern. Lowest rates occurred in July and August and the highest rates in September for asthma, and after December for COPD and RTI. The increase in rates for 30 days before and after school return in September was greatest for children with asthma <15 years (2.4–2.6×). Event rates fell after school return in January for all three conditions ranging from 10–25%, and no change followed March break for asthma and COPD. Human rhinovirus was prevalent in summer with a modest relationship to asthma rates in September. The prevalence of respiratory syncytial virus, influenza A and coronavirus was associated with sustained event rates for COPD and RTIs.

Conclusions

Asthma, COPD and RTIs increase in September but do not occur after return to school in January and March. Human rhinovirus is associated with ED visits and admissions only in September.

Asthma, COPD and RTIs increase in September but do not occur after return to school in January and March. Human RV is associated with ED visits and admissions only in September.https://bit.ly/3jEy168

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.

Protective effect of heart rate variability biofeedback on stress-induced lung function impairment in asthma

Psychological stress can provoke airway constriction in asthmatic patients, which may be because of autonomic nervous system dysfunction in asthma. We investigated the effect of enhancing respiratory sinus arrhythmia using heart rate variability biofeedback (HRV-BF) on spirometry performance and HRV indices during stress induced by Stroop Color-Word interference test in asthmatic patients and healthy volunteers. Stress caused decrease in FEV1%, FVC%, and PEF% compared to baseline in asthmatic patients, but not in healthy subjects. A single short duration episode of HRV-BF not only had a protective effect on stress-induced airway constriction, but also significantly augmented the level of FEV1% and FVC% as compared with their own baseline. Also, there was a significant correlation between HRV changes and the augmentation of spirometry performance in asthmatic patients receiving HRV-BF. Our findings indicated that even a single short duration episode of HRV-BF can decrease susceptibility to stress-induced lung function impairment in patients with asthma, which may be through the modulation of respiratory sinus arrhythmia.

Dysfunctional Breathing in Children and Adults With Asthma

Asthma occurs across the life course. Its optimal treatment includes the use of personalized management plans that recognize the importance of co-morbidities including so-called "dysfunctional breathing." Such symptoms can arise as a result of induced laryngeal obstruction (ILO) or alterations in the mechanics of normal breathing called breathing pattern disorders. Whilst these two types of breathing abnormalities might be related, studies tend to focus on only one of them and do not consider their relationship. Evidence for these problems amongst childhood asthmatics is largely anecdotal. They seem rare in early childhood. Both types are more frequently recognized in the second decade of life and girls are affected more often. These observations tantalizingly parallel epidemiological studies characterizing the increasing prevalence and severity of asthma that also occurs amongst females after puberty. Exercise ILO is more common amongst adolescents and young adults. It should be properly delineated as it might be causally related to specific treatable factors. More severe ILO occurring at rest and breathing pattern disorders are more likely to be occurring within a psychological paradigm. Dysfunctional breathing is associated with asthma morbidity through a number of potential mechanisms. These include anxiety induced breathing pattern disorders and the enhanced perception of subsequent symptoms, cooling and drying of the airways from hyperventilation induced hyperresponsiveness and a direct effect of emotional stimuli on airways constriction via cholinergic pathways. Hyperventilation is the most common breathing pattern disorder amongst adults. Although not validated for use in asthma, the Nijmegen questionnaire has been used to characterize this problem. Studies show higher scores amongst women, those with poorly controlled asthma and those with psychiatric problems. Evidence that treatment with breathing retraining techniques is effective in a primary care population including all types of asthmatics suggests the problem might be more ubiquitous than just these high-risk groups. Future challenges include the need for studies characterizing all types of dysfunctional breathing in pediatric and adult patient cohorts and clearly defined, age appropriate, interventional studies. Clinicians caring for asthmatics in all age groups need to be aware of these co-morbidities and routinely ask about symptoms that suggest these problems.

The effects of caregiver depression on childhood asthma: Pathways and mechanisms

OBJECTIVE

To review the literature regarding the effects of caregiver depression on childhood asthma and integrate the findings into a multilevel model of pathways by which these effects occur to further the understanding of the complex biopsychosocial nature of childhood asthma and the key role that is played by caregiver depression.

DATA SOURCES

PubMed was searched for articles published from 2007 to the present (10-year search), and Google Scholar was searched for articles published in 2017 and 2018 to identify the most recent publications.

STUDY SELECTIONS

Studies selected were recent, empirical, or meta-analytic, conducted in humans, and had specific relevance to one or more of the identified pathways. Articles published before 2007 were included if deemed essential because they addressed key pathways, for which there were no more recent articles.

RESULTS

Review of the literature substantiates that caregiver depression plays a key role in the socioeconomic, familial, psychological, and biological cascade of effects on childhood asthma. Childhood asthma outcomes are affected indirectly by socioeconomic status and family stress mediated by caregiver depression, which affects disease management, and/or stress and depression in the child, which, in turn, affect asthma through alterations in immune modulation and autonomic regulation.

CONCLUSION

Findings indicate that future research should concentrate on mediators and moderators to further clarify the complex interplay of these factors that affect childhood asthma. The findings also have substantial translational implications. Given that child stress and depression contribute to asthma disease activity and that treating caregiver depression improves child stress and depression, there is strong rationale for treating depressed caregivers of children with asthma as a component means of improving childhood asthma control.

The interplay between neuroendocrine activity and psychological stress-induced exacerbation of allergic asthma

Psychological stress is recognized as a key factor in the exacerbation of allergic asthma, whereby brain responses to stress act as immunomodulators for asthma. In particular, stress-induced enhanced type 2 T-helper (Th2)-type lung inflammation is strongly associated with asthma pathogenesis. Psychological stress leads to eosinophilic airway inflammation through activation of the hypothalamic-pituitary-adrenal pathway and autonomic nervous system. This is followed by the secretion of stress hormones into the blood, including glucocorticoids, epinephrine, and norepinephrine, which enhance Th2 and type 17 T-helper (Th17)-type asthma profiles in humans and rodents. Recent evidence has shown that a defect of the μ-opioid receptor in the brain along with a defect of the peripheral glucocorticoid receptor signaling completely disrupted stress-induced airway inflammation in mice. This suggests that the stress response facilitates events in the central nervous and endocrine systems, thus exacerbating asthma. In this review, we outline the recent findings on the interplay between stress and neuroendocrine activities followed by stress-induced enhanced Th2 and Th17 immune responses and attenuated regulatory T (Treg) cell responses that are closely linked with asthma exacerbation. We will place a special focus on our own data that has emphasized the continuity from central sensing of psychological stress to enhanced eosinophilic airway inflammation. The mechanism that modulates psychological stress-induced exacerbation of allergic asthma through neuroendocrine activities is thought to involve a series of consecutive pathological events from the brain to the lung, which implies there to be a "neuropsychiatry phenotype" in asthma.

A pharmacological evidence for the presence of antihistaminic and anticholinergic activities in Equisetum debile Roxb

Objective:

The study was designed to evaluate possible antihistaminic and anticholinergic activities of Equisetum debile.

Materials and Methods:

Effects of crude ethanolic (Ed.Eth) and effects of crude aqueous (Ed.Aq) extracts of E. debile were studied using isolated guinea pig ileum, rabbit jejunum, and rabbit trachea. Tissue responses were recorded using isotonic and isometric transducers, connected with PowerLab data acquisition system.

Results:

A dose-dependent (0.1–0.3 mg/ml) rightward shift was demonstrated in histamine concentration-response curves. Whereas a complete relaxation of carbachol (1 μM)-induced contractions in isolated rabbit jejunum (3 mg/ml) and tracheal (10 mg/ml) preparations was observed, similar to dicyclomine at 1 and 3 μM, respectively. However, no significant difference between the effects of Ed.Eth and Ed.Aq was observed.

Conclusion:

Study provides pharmacological evidence for the presence of antihistaminic and anticholinergic activities in crude extracts of E. debile and also highlight its medicinal significance in the management of airway and gastrointestinal disorders.

Arginine Vasopressin Alters Both Spontaneous and Phase-Locked Synaptic Inputs to Airway Vagal Preganglionic Neuron via Activation of V1a Receptor: Insights into Stress-Related Airway Vagal Excitation

The airway vagal preganglionic neurons (AVPNs) in the external formation of the nucleus ambiguus (eNA) play a major role in the vagal control of tracheobronchial smooth muscle tone and maintenance of airway resistance. The eNA receives vasopressinergic projection from the hypothalamic paraventricular nucleus (PVN), the key node for the genesis of psychological stress. Since airway vagal excitation is reportedly to be associated with the psychological stress-induced/exacerbated airway hyperresponsiveness in asthmatics, arginine vasopressin (AVP) might be involved in stress-related airway vagal excitation. However, this possibility has not been validated. This study aimed to test whether and how AVP regulates AVPNs. In rhythmically active medullary slices of newborn rats, retrogradely labeled AVPNs were identified as inspiratory-activated and inspiratory-inhibited AVPNs (IA- and II-AVPNs) using patch-clamp techniques according to their inspiratory-related firing behavior and synaptic activities. The results show that under current clamp, AVP depolarized both IA- and II-AVPNs, and significantly increased their spontaneous firing rate. Under voltage clamp, AVP elicited a slow inward current, and significantly increased the frequency of spontaneous excitatory postsynaptic currents (sEPSCs) in both types of AVPNs. In addition, AVP significantly enhanced the phase-locked excitatory inspiratory inward current in inspiratory-activated airway vagal preganglionic neurons (IA-AVPNs), but significantly suppressed the phase-locked inhibitory inspiratory outward current in II-AVPNs. In both types AVPNs, AVP significantly increased the frequency and amplitude of pharmacologically isolated spontaneous GABAergic and glycinergic inhibitory postsynaptic currents (IPSCs). All of the AVP-induced effects were prevented by SR49059, an antagonist of V_1a receptors, but unaffected by SSR149415, an antagonist of V_1b receptors. AVP did not cause significant changes in the miniature excitatory postsynaptic currents (mEPSCs), miniature inhibitory postsynaptic currents (mIPSCs) and membrane input resistance of either type of AVPNs. These results demonstrate that AVP, via activation of V_1a receptors, enhanced the spontaneous excitatory and inhibitory inputs similarly in the two types of AVPNs, but differentially altered their phase-locked inspiratory excitatory and inhibitory inputs. The overall effects of AVP are excitatory in both types AVPNs. These results suggest that increased central AVP release may be involved in the stress-induced augmentation of airway vagal activity, and, consequently, the induction or exacerbation of some airway diseases.

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.

A linear model for event-related respiration responses

BACKGROUND

Cognitive processes influence respiratory physiology. This may allow inferring cognitive states from measured respiration. Here, we take a first step towards this goal and investigate whether event-related respiratory responses can be identified, and whether they are accessible to a model-based approach.

NEW METHOD

We regard respiratory responses as the output of a linear time invariant system that receives brief inputs after psychological events. We derive average responses to visual targets, aversive stimulation, and viewing of arousing pictures, in interpolated respiration period (RP), respiration amplitude (RA), and respiratory flow rate (RFR). We then base a Psychophysiological Model (PsPM) on these averaged event-related responses. The PsPM is inverted to yield estimates of cognitive input into the respiratory system. This method is validated in an independent data set.

RESULTS

All three measures show event-related responses, which are captured as non-zero response amplitudes in the PsPM. Amplitude estimates for RA and RFR distinguish between picture viewing and the other tasks. This pattern is replicated in the validation experiment.

COMPARISON WITH EXISTING METHODS

Existing respiratory measures are based on relatively short time-intervals after an event while the new method is based on the entire duration of respiratory responses.

CONCLUSION

Our findings suggest that interpolated respiratory measures show replicable event-related response patterns. PsPM inversion is a suitable approach to analysing these patterns, with a potential to infer cognitive processes from respiration.

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.

Cough variant asthma patients are more depressed and anxious than classic asthma patients

OBJECTIVE

Many recent studies have indicated that depression and anxiety are more common in asthmatic patients than in the general population and psychological stress can lead to asthma exacerbations, but no study specifically targets cough variant asthma (CVA) patients. The purpose of this study was to evaluate depression and anxiety levels in CVA patients compared with classic asthma patients and to identify the psychological features of CVA patients.

METHODS

Fifty-nine outpatients with CVA and 128 outpatients with classic asthma were interviewed about psychosomatic and psychiatric symptoms, and they underwent three psychological tests: Self-rating Depression Scale (SDS), State-Trait Anxiety Inventory (STAI), and Comprehensive Asthma Inventory (CAI). They were ultimately screened for major and minor depression, dysthymia, panic disorder, generalized anxiety disorder, social anxiety disorder, and other anxiety disorders.

RESULTS

CVA patients showed higher SDS and STAI scores than classic asthma patients, and mood disorders and anxiety disorders were more common than in classic asthma outpatients. The psychological factors 'frustration', 'fright into illness', and 'distorted lifestyle' were more prominent in CVA patients than in classic asthma patients.

CONCLUSION

CVA patients are on average more depressed and anxious than classic asthma outpatients. Though CVA appears pathologically to be just an early stage of typical asthma, the psychological stress may often be more serious than in asthma controlled by medication, which may explain why CVA cannot be controlled by a bronchodilator alone and patients often require no less intense therapy than for severe asthma.

Asthma and odors: the role of risk perception in asthma exacerbation

OBJECTIVE

Fragrances and strong odors have been characterized as putative triggers that may exacerbate asthma symptoms and many asthmatics readily avoid odors and fragranced products. However, the mechanism by which exposure to pure, non-irritating odorants can elicit an adverse reaction in asthmatic patients is still unclear and may involve both physiological and psychological processes. The aim of this study was to investigate how beliefs about an odor's relationship to asthmatic symptoms could affect the physiological and psychological responses of asthmatics.

METHODS

Asthmatics classified as 'moderate-persistent', according to NIH criteria, were exposed for 15 min to a fragrance which was described either as eliciting or alleviating asthma symptoms. During exposure, participants were asked to rate odor intensity, perceived irritation and subjective annoyance while physiological parameters such as electrocardiogram, respiratory rate, and end tidal carbon dioxide (etCO₂) were recorded. Before, immediately after, and at 2 and 24h post-exposure, participants were required to subjectively assess their asthma symptom status using a standardized questionnaire. We also measured asthma status at each of those time points using objective parameters of broncho-constriction (spirometry) and measures of airway inflammation (exhaled nitric oxide, FeNO).

RESULTS

Predictably, manipulations of perceived risk altered both the quality ratings of the fragrance as well as the reported levels of asthma symptoms. Perceived risk also modulated the inflammatory airway response.

CONCLUSIONS

Expectations elicited by smelling a perceived harmful odor may affect airway physiology and impact asthma exacerbations.

Asthma and depression: the Cooper Center Longitudinal Study

BACKGROUND

Prior research suggests a possible association between asthma and depression.

OBJECTIVE

To examine the association between asthma and depressive symptoms, controlling for asthma medications, lung function, and overall health.

METHODS

We conducted a cross-sectional study of 12,944 adults who completed physician-based preventive health examinations at the Cooper Clinic from 2000 to 2012. Information on medical histories, including asthma and depression, and medications were collected. Participants reported overall health status, completed spirometry testing, and underwent depression screening using the 10-item Center for Epidemiologic Studies Depression Scale (CES-D). Dependent variables of current depressive symptoms (CES-D scores ≥10) and lifetime history of depression were separately modeled using logistic regression with independent variables, including demographics, spirometry, asthma controller medications, and patient-reported health status.

RESULTS

The sample was predominantly white and well educated. The prevalence of asthma was 9.0%. Asthma was associated with an odds ratio (OR) of 1.41 (95% CI, 1.16-1.70; P < .001) of current depressive symptoms based on CES-D score. Asthma was also associated with lifetime history of depression (OR, 1.66; 95% CI, 1.40-1.95; P < .001). Neither lung function nor asthma controller medications were significantly associated with depression.

CONCLUSION

Asthma was associated with increased prevalence of current depressive symptoms and lifetime depression in a large sample of relatively healthy adults. These findings suggest that the increased likelihood of depression among patients with asthma does not appear to be exclusively related to severe or poorly controlled asthma. People with asthma, regardless of severity, may benefit from depression screening in clinical settings.

Perceived triggers of asthma: key to symptom perception and management

Adequate asthma management depends on an accurate identification of asthma triggers. A review of the literature on trigger perception in asthma shows that individuals vary in their perception of asthma triggers and that the correlation between self-reported asthma triggers and allergy tests is only modest. In this article, we provide an overview of psychological mechanisms involved in the process of asthma triggers identification. We identify sources of errors in trigger identification and targets for behavioural interventions that aim to improve the accuracy of asthma trigger identification and thereby enhance asthma control.

A review of psychological dysfunction in asthma: affective, behavioral and cognitive factors

BACKGROUND

The research on psychological dysfunction in asthma is extensive but heterogeneous. We undertook a narrative review about the effects of psychological dysfunction on asthma.

METHODS

Electronic searches of MEDLINE, EMBASE, CINAHL and the Cochrane Library were conducted, supplemented by hand-searching bibliographies and seeking expert opinion.

RESULTS

The impact of psychological factors on asthma can be classified according to dysfunction in the domains of affect, behavior and cognition. Affective or emotional disturbance may lead to poor asthma control by directly modulating disease activity. Maladaptive behaviors may occur in asthma patients. These include maladaptive breathing behaviors, such as impaired voluntary drive to breathe and dysfunctional breathing, as well as impaired asthma health behaviors, that is, a coordinated range of activities performed to maintain good disease control. Dysfunctional cognitions (thoughts and beliefs) about asthma and impaired cognitive processing of the perception of dyspnea are associated with poorly controlled disease and asthma deaths, respectively. The three domains of psychological dysfunction are often closely intertwined, leading to vicious circles.

CONCLUSIONS

We have conceptualized psychological dysfunction in asthma using a framework consisting of affect, behavior and cognition. Their influences are intertwined and complex. Future research should focus on the formulation of a psychological assessment tool based on this framework and evaluating its efficacy in improving asthma outcomes.

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.

Stress, asthma, and respiratory infections: pathways involving airway immunology and microbial endocrinology

Stress and infections have long been independently associated with asthma pathogenesis and exacerbation. Prior research has focused on the effect of psychological stress on Th cells with particular relevance to atopic asthma. In this review, we propose new perspectives that integrate the role of infection in the relationship between psychological stress and asthma. We highlight the essential role of the mucosal epithelia of the airways in understanding the interaction between infections and the stress-asthma relationship. In addition, we review findings suggesting that psychological stress not only modulates immune processes, but also the pathogenic qualities of bacteria, with implications for the pathogenesis and exacerbation asthma.

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.

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.

Cough triggers and their pathophysiology in patients with prolonged or chronic cough

BACKGROUND

The character or timing of chronic cough is considered to be unpredictable for diagnosing its cause. However, the associations of cough triggers with cough pathophysiology remains unknown.

METHODS

We developed a closed questionnaire listing 18 triggers that were reported by ≥1% of 213 patients in a retrospective survey. Using this questionnaire, patients with cough-predominant or cough-variant asthma (n = 140) and those with non-asthmatic cough (54) were asked whether their cough was induced by the listed triggers. Associations of triggers with causes of cough, airway sensitivity to inhaled methacholine, exhaled nitric oxide (NO) levels, number of sensitizing allergens, and scores from gastroesophageal reflux (GER) questionnaires were examined. Factor analysis was used to categorize variables, including the 12 most common cough triggers, diagnosis of asthmatic cough, airway sensitivity, and exhaled NO levels.

RESULTS

"Cold air" and "fatigue/stress" induced cough more often in asthmatic coughers than in non-asthmatic coughers. "Spices" and "meals" induced cough more frequently in GER-coughers (n = 19). Patients who marked "cold air" as the trigger were more sensitive to inhaled methacholine and showed higher exhaled NO levels than those who did not mark this trigger. The "post-nasal drip" trigger was associated with elevated exhaled NO levels, and this association was mainly exhibited by patients with cough-predominant asthma. The triggers "pollen" and "mold smell" were associated with a number of sensitizing allergens. The number of triggers was weakly associated with GER scores. By factor analysis, "cold air," "fatigue/stress," asthmatic cough, airway hypersensitivity, and elevated NO levels were categorized into the same factor.

CONCLUSIONS

Several cough triggers may reflect the pathophysiology of prolonged or chronic cough.

Generalized anxiety disorder is associated with reduced lung function in the Vietnam Experience Study

BACKGROUND

There is no clear consensus in the few studies to have explored the relationship between major mental health disorders and lung function. The present study examined the cross-sectional associations of generalized anxiety disorder (GAD) and major depressive disorder (MDD) with lung function in a large study of male US veterans.

METHODS

Participants (N = 4256) were drawn from the Vietnam Experience Study. From military files, telephone interviews, and a medical examination, anthropometric, sociodemographic, and health data were collected. One-year prevalence of GAD and MDD was determined using DSM-III criteria. Forced expiratory volume in 1 second was measured by spirometry.

RESULTS

In models that adjusted for age and height, both GAD (p < .001) and MDD (p = .004) were associated with lower forced expiratory volume in 1 second. In models additionally adjusting for weight, place of service, ethnicity, marriage, smoking, alcohol consumption, income, education, and major illness, GAD was still associated with poorer lung function (p = .01), whereas MDD was not (p = .18).

CONCLUSIONS

Depression has very much been the focus of studies on mental health and physical health status. The current findings suggest that future research should perhaps pay equal attention to GAD.

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.

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

Earlier research found autonomic and airway reactivity in asthma patients when they were exposed to blood-injection-injury (BII) stimuli. We studied oscillatory resistance (R(os)) in asthma and BII phobia during emotional and disease-relevant films and examined whether muscle tension counteracts emotion-induced airway constriction. Fifteen asthma patients, 12 BII phobia patients, and 14 healthy controls viewed one set of negative, positive, neutral, BII-related, and asthma-related films with leg muscle tension and a second set without. R(os), ventilation, cardiovascular activity, and skin conductance were measured continuously. R(os) was higher during emotional compared to neutral films, particularly during BII material, and responses increased from healthy over asthmatic to BII phobia participants. Leg muscle tension did not abolish R(os) increases. Thus, the airways are particularly responsive to BII-relevant stimuli, which could become risk factors for asthma patients.

Acute stress-induced increases in exhaled nitric oxide in asthma and their association with endogenous cortisol

RATIONALE

psychosocial stress is known to influence the pathophysiology of asthma. Although stress has been linked to serum markers of inflammatory activity and exaggerated response to allergen challenge in asthma, few studies have examined inflammatory activity in the airways linked to psychosocial stress alone. Furthermore, although studies have demonstrated lower levels or reactivity of endogenous cortisol in asthma, the association with airway inflammatory activity in stress remains unexplored.

OBJECTIVES

we therefore studied airway inflammation and cortisol response to a standardized laboratory task inducing acute psychosocial stress.

METHODS

airway inflammation by the fraction of exhaled nitric oxide (FeNO) and saliva cortisol were sampled before and up to 45 minutes after experimental challenge with the Trier Social Stress Test in 20 adult patients with asthma and 19 healthy control subjects. Respiratory inductive plethysmography was used to control for changes in ventilatory activity that impact FeNO levels.

MEASUREMENTS AND MAIN RESULTS

FeNO levels were generally higher in patients with asthma than healthy control subjects and salivary cortisol levels were lower. Increases in cortisol levels were observed after the stress protocol in both groups (P < 0.001). FeNO levels at the time of peak cortisol increase after stress were significantly higher than before stress in both groups (P < 0.05). FeNO increases were independent of changes in ventilation. In patients with asthma, higher cortisol levels and stronger increases in cortisol after stress were significantly associated with smaller increases in FeNO (P < 0.05).

CONCLUSIONS

acute psychosocial stress alone increases airway inflammatory markers and this increase is attenuated by stronger stress-related activity of the hypothalamic-pituitary-adrenal axis in asthma.

Emotional reactivity of the airways in asthma: consistency across emotion-induction techniques and emotional qualities

Considerable individual differences exist in asthma patients' airway responses to emotional stimuli, but little is known about the generalization of such responses across situations or states of airways constriction. Fifty-four asthma patients and 25 healthy controls viewed in two separate sessions, films and blocks of pictures from each of three emotional qualities, pleasant, unpleasant, and neutral. At the beginning of each session, patients received a placebo or anti-cholinergic bronchodilator (ipratropium bromide), respectively, in a randomized double-blind design. Respiratory resistance, reactance and impedance were recorded throughout stimulus presentations with impulse oscillometry. Resistance increases showed a moderate degree of generalization across unpleasant films and pictures, unpleasant and pleasant pictures, as well as cholinergic blockade and placebo. Thus, the intensity of airway responses to unpleasant emotional stimuli is a moderately stable characteristic of asthma patients. In addition to the central airway, peripheral and extrathoracic airways may also contribute the consistency of such responses.