Dysfunctional breathing phenotype in adults with asthma - incidence and risk factors

[Effects of pulmonary rehabilitation on dysfunctional respiratory patterns in patients with uncontrolled asthma]

PURPOSE

Dysfunctional breathing patterns (DAM) are deviations from physiologic breathing patterns. DAM seem to be associated with lower asthma control. To date, it is unclear what effect inpatient rehabilitation can have on this problem. The aim of this work is to investigate the effect of pulmonary rehabilitation (PR) on DAM.

METHODS

The data are based on a randomized controlled trial with a waiting control group. The intervention group (IG) received PR 4 weeks after application approval and the control group (KG) after 5 months. Dysfunctional breathing was assessed by Nijmegen-Questionnaire (NQ). Values ≥ 23 points indicate an existing DAM. Values at the end of rehabilitation (T2) and after three months (T3) were compared (analysis of covariance). Supplemental moderator analysis was performed to examine whether the effect of PR was related to baseline NQ scores.

RESULTS

Significant differences in NQ score are found between IG (n=202) and KG (n=210) at T2 (AMD=10.5; 95%CI [9; 12]; d=1.4; p<0.001) and at T3 (AMD=5.8; 95%CI [4.3; 7.3]; d=0.8; p<0.001). There is an interaction effect between the difference in NQ score between the groups at T2 and baseline at T0 (b=5.6; 95%CI [2.2; 11.9]; p<0.001). At T3, this interaction effect was no longer detectable (b=4.5; 95%CI [-3.1; 14.1]; p=807).

CONCLUSION

Inpatient, multimodality, and interdisciplinary PR is associated with significant and clinically relevant improvement in DAM both at discharge and 3 months later. In the short term, patients with existing DAM benefit more from PR than patients without DAM.

Hyperventilation syndrome in children with asthma

BACKGROUND

Hyperventilation syndrome (HVS) may be associated with asthma. In the absence of a gold standard diagnosis for children, its impact on asthma has been rarely assessed.

OBJECTIVE

To assess the impact of HVS on the symptoms and lung function of children with asthma and determine the diagnostic value of the Nijmegen questionnaire in comparison to a hyperventilation test (HVT).

METHODS

Data from asthmatic children followed in the department of Pediatric Pulmonology of Necker Hospital and explored for HVS were retrospectively analyzed. HVS was diagnosed by a positive HVT. Asthma exacerbations, control and lung function were assessed in children with or without a positive HVT. The sensitivity and specificity of the Nijmegen questionnaire were determined relative to the positivity of a HVT. The Nijmegen questionnaire threshold was ≥23.

RESULTS

Data from 112 asthmatic children, median age 13.9 years [11.6-16], were analyzed. Twenty-eight children (25%) had mild or moderate asthma and 84 (75%) severe asthma. The HVT was performed on 108 children and was negative for 34 (31.5%) and positive for 74 (68.5%). The number of asthma exacerbations in the past 12 months, Asthma Control Test (ACT) score, and lung function did not differ between children with a positive HVT and a negative HVT. The Nijmegen questionnaire was administered to 103 children. Its sensitivity was 56.3% and specificity 56.3%.

CONCLUSION

The symptoms and lung function of adolescents with asthma are not affected by the presence of HVS. The sensitivity and specificity of the Nijmegen questionnaire are low.

Puzzled by dysfunctional breathing disorder(s)? Consider the Bayesian brain hypothesis!

There is currently growing clinical concern regarding dysfunctional breathing disorder(s) (DBD), an umbrella term for a set of multidimensional clinical conditions that are characterized by altered breathing pattern associated with a variety of intermittent or chronic symptoms, notably dyspnea, in the absence or in excess of, organic disease. However, several aspects of DBD remain poorly understood and/or open to debate, especially the inconsistent relationship between the array of experienced symptoms and their supposedly underlying mechanisms. This may be partly due to a more general problem, i.e., the prevailing way we conceptualize symptoms. In the present article, after a brief review of the different aspects of DBD from the current perspective, I submit a call for considering DBD under the innovating perspective of the Bayesian brain hypothesis, i.e., a potent and novel model that fundamentally changes our views on symptom perception.

The Detrimental Clinical Associations of Anxiety and Depression with Difficult Asthma Outcomes

Difficult asthma describes asthma in which comorbidities, inadequate treatment, suboptimal inhaler technique and/or poor adherence impede good asthma control. The association of anxiety and depression with difficult asthma outcomes (exacerbations, hospital admissions, asthma control, etc.) is unclear. This study assessed the clinical associations of anxiety and depression with difficult asthma outcomes in patients with a specialist diagnosis of difficult asthma. Using real-world data, we retrospectively phenotyped patients from the Wessex Asthma Cohort of Difficult Asthma (N = 441) using clinical diagnoses of anxiety and depression against those without anxiety or depression (controls). Additionally, we stratified patients by severity of psychological distress using the Hospital Anxiety and Depression Scale (HADS). We found that depression and/or anxiety were reported in 43.1% of subjects and were associated with worse disease-related questionnaire scores. Each psychological comorbidity group showed differential associations with difficult asthma outcomes. Anxiety alone (7.9%) was associated with dysfunctional breathing and more hospitalisations [anxiety, median (IQR): 0 (2) vs. controls: 0 (0)], while depression alone (11.6%) was associated with obesity and obstructive sleep apnoea. The dual anxiety and depression group (23.6%) displayed multimorbidity, worse asthma outcomes, female predominance and earlier asthma onset. Worse HADS-A scores in patients with anxiety were associated with worse subjective outcomes (questionnaire scores), while worse HADS-D scores in patients with depression were associated with worse objective (ICU admissions and maintenance oral corticosteroid requirements) and subjective outcomes. In conclusion, anxiety and depression are common in difficult asthma but exert differential detrimental effects. Difficult asthma patients with dual anxiety and depression experience worse asthma outcomes alongside worse measures of psychological distress. There is a severity-gradient association of HADS scores with worse difficult asthma outcomes. Collectively, our findings highlight the need for holistic, multidisciplinary approaches that promote early identification and management of anxiety and depression in difficult asthma patients.

Associations of symptoms of anxiety and depression with health-status, asthma control, dyspnoea, dysfunction breathing and obesity in people with severe asthma

BACKGROUND

Anxiety and depression are comorbidities of severe asthma. However, clinical characteristics associated with coexisting severe asthma and anxiety/depression are poorly understood. The study objective is to determine clinical characteristics associated with anxiety and depressive symptoms in severe asthma.

METHODS

Severe asthma participants (N = 140) underwent a multidimensional assessment. Categorization of symptoms of anxiety and depression were based on HADS scale sub-scores and divided into four groups (< 8 on both subscales; ≥ 8 on one subscale; ≥ 8 on both subscales). Clinical characteristics were compared between subgroups. Multivariate logistic regression determined associations of clinical characteristics and anxiety and/or depressive symptoms in people with severe asthma.

RESULTS

Participants were (mean ± SD) 59.3 ± 14.7 years old, and 62% female. There were 74 (53%) severe asthma participants without symptoms of anxiety/depression, 11 (7%) with symptoms of anxiety, 37 (26%) with symptoms of depression and 18 (13%) with symptoms of anxiety and depression. Quality of life impairment was greater in participants with symptoms of depression (4.4 ± 1.2) and combined symptoms of anxiety and depression (4.4 ± 1.1). Asthma control was worse in those with symptoms of depression (2.9 ± 1.1) and combined anxiety and depression (2.6 ± 1.0). In multivariate models, dysfunctional breathing was associated with symptoms of anxiety (OR = 1.24 [1.01, 1.53]). Dyspnoea was associated with symptoms of depression (OR = 1.90 [1.10, 3.25]). Dysfunctional breathing (OR 1.16 [1.04, 1.23]) and obesity (OR 1.17 [1.00, 1.35]) were associated with combined symptoms of anxiety and depression.

CONCLUSION

People with severe asthma and anxiety and/or depressive symptoms have poorer QoL and asthma control. Dyspnoea, dysfunctional breathing and obesity are associated with these symptoms. These key clinical characteristics should be targeted in severe asthma management.

Neck Pain and Disability: Are They Related to Dysfunctional Breathing and Stress?

Purpose: People with neck pain are likely to have negative respiratory findings. The purpose of this study was to investigate the relationship between neck pain and dysfunctional breathing and to examine their relationship to stress. Method: This cross-sectional study included 49 participants with neck pain and 49 age- and sex-matched controls. We measured neck pain using the numeric rating scale (NRS); neck disability using the Neck Disability Index (NDI); dysfunctional breathing using the Nijmegen Questionnaire (NQ), Self-Evaluation of Breathing Questionnaire (SEBQ), breath hold time, and respiratory rate (RR); and stress using the Perceived Stress Scale (PSS). Results:Participants with neck pain scored higher on the NQ ( p < 0.001) and the SEBQ ( p < 0.001) than controls. NQ and SEBQ scores correlated moderately with NDI scores ( r > 0.50; 95% CI: 0.25, 0.68 and 0.33, 0.73, respectively) and PSS scores ( r > 0.50; 95% CI: 0.29, 0.78 and 0.31, 0.73, respectively). SEBQ scores showed a fair correlation with NRS scores and RR a fair correlation with NDI scores. Conclusions: Participants with neck pain had more dysfunctional breathing symptoms than participants without neck pain, and dysfunctional breathing was correlated with increased neck disability and increased stress. The NQ and SEBQ can be useful in assessing dysfunctional breathing in patients with neck pain.

Asthma and Comorbid Conditions-Pulmonary Comorbidity

Pulmonary comorbidities can increase disease severity and health care costs associated with asthma management. Vocal cord dysfunction/inducible laryngeal obstruction is a common comorbidity that results from intermittent laryngeal obstruction. Patients describe distinct episodes of dyspnea that do not respond to bronchodilators. Inspiratory stridor is common. The gold standard diagnostic testing strategy is continuous laryngoscopy performed during exercise or irritant challenges. Dysfunctional breathing (DB) is an overarching term that describes conditions with a chronic change in the pattern of breathing that results in pulmonary and extrapulmonary symptoms. The prevalence of DB in asthma is up to 30%, and breathing retraining can improve symptoms and quality of life in people with DB and asthma. Asthma-chronic obstructive pulmonary disease overlap (ACO) refers to both asthmatics who develop fixed airflow obstruction after a history of exposure to smoke or biomass and patients with chronic obstructive pulmonary disease who have "asthmatic features" such as a large bronchodilator response, elevated levels of serum IgE, or peripheral eosinophil counts ≥300 per μL. Triple inhaler therapy with inhaled corticosteroid/long-acting beta-agonist/long-acting muscarinic should be considered in people with ACO and severe symptoms or frequent exacerbations. The clinical expression of bronchiectasis involves persistent mucus hypersecretion, recurrent exacerbations of infective bronchitis, incompletely reversible airflow obstruction, and lung fibrosis and can occur in up to 30% of adults with longstanding asthma. The treatable traits strategy is a useful model of care to manage the complexity and heterogeneity of asthma with pulmonary comorbidity.

Changes in quantifiable breathing pattern components predict asthma control: an observational cross-sectional study

Background

Breathing pattern disorders are frequently reported in uncontrolled asthma. At present, this is primarily assessed by questionnaires, which are subjective. Objective measures of breathing pattern components may provide additional useful information about asthma control. This study examined whether respiratory timing parameters and thoracoabdominal (TA) motion measures could predict and classify levels of asthma control.

Methods

One hundred twenty-two asthma patients at STEP 2- STEP 5 GINA asthma medication were enrolled. Asthma control was determined by the Asthma Control Questionnaire (ACQ7-item) and patients divided into ‘well controlled’ or ‘uncontrolled’ groups. Breathing pattern components (respiratory rate (RR), ratio of inspiration duration to expiration duration (Ti/Te), ratio of ribcage amplitude over abdominal amplitude during expiration phase (RCampe/ABampe), were measured using Structured Light Plethysmography (SLP) in a sitting position for 5-min. Breath-by-breath analysis was performed to extract mean values and within-subject variability (measured by the Coefficient of Variance (CoV%). Binary multiple logistic regression was used to test whether breathing pattern components are predictive of asthma control. A post-hoc analysis determined the discriminant accuracy of any statistically significant predictive model.

Results

Fifty-nine out of 122 asthma patients had an ACQ7-item < 0.75 (well-controlled asthma) with the rest being uncontrolled (n = 63). The absolute mean values of breathing pattern components did not predict asthma control (R² = 0.09) with only mean RR being a significant predictor (p < 0.01). The CoV% of the examined breathing components did predict asthma control (R² = 0.45) with all predictors having significant odds ratios (p < 0.01). The ROC curve showed that cut-off points > 7.40% for the COV% of the RR, > 21.66% for the CoV% of Ti/Te and > 18.78% for the CoV% of RCampe/ABampe indicated uncontrolled asthma.

Conclusion

The within-subject variability of timing parameters and TA motion can be used to predict asthma control. Higher breathing pattern variability was associated with uncontrolled asthma suggesting that irregular resting breathing can be an indicator of poor asthma control.

Comparative analysis between available challenge tests in the hyperventilation syndrome

BACKGROUND

The hyperventilation syndrome (HVS) is characterized by somatic/ psychological symptoms due to sustained hypocapnia and respiratory alkalosis without any organic disease.

OBJECTIVE

The purpose of this study was to compare ventilatory parameters and symptoms reproducibility during the hyperventilation provocation test (HVPT) and cardiopulmonary exercise test (CPET) as diagnostic tools in patients with HVS, and to identify the most frequent etiologies of the HVS by a systematic assessment.

METHODS

After exclusion of organic causes, 59 patients with HVS according to Nijmegen's questionnaire (NQ) score ≥23 with associated hypocapnia (PaCO₂/PET_CO2<35 mm Hg) were studied.

RESULTS

The most frequent comorbidities of HVS were anxiety and asthma (respectively 95% and 73% of patients). All patients described ≥3 symptoms of NQ during the HVPT vs 14% of patients during the CPET (p<0.01). For similar maximal ventilation (61 L/min during HVPT vs 60 L/min during CPET), the median level of PET_CO2 decreased from 30 mmHg at baseline to 15 mmHg during hyperventilation and increased from 31 mmHg at baseline to 34 mmHg at peak exercise (all p<0.01). No significant difference for the ventilatory parameters was found between patients with HVS (n = 16) and patients with HVS + asthma (n = 43).

CONCLUSIONS

In term of symptoms reproducibility, HVPT is a better diagnostic tool than CPET for HVS. An important proportion of patients with HVS has an atypical asthma previously misdiagnosed. The exercise-induced hyperventilation did not induce abnormal reduction in PET_CO2, suggesting that the exercise could be a therapeutic tool in HVS.

The impact of mental toughness and postural abnormalities on dysfunctional breathing in athletes

Background: While asthma and exercise-induced bronchoconstriction (EIB) can explain some cases of exertional dyspnea, the differential diagnosis of dyspnea is extensive. Dysfunctional breathing (DB) is a condition that is often overlooked and underdiagnosed. Pharmacologic treatments are available and widely utilized by clinicians for exertional dyspnea, but a better understanding of the non-pharmacologic treatments as well as psychological factors that play a role in DB can provide professional, elite amateurs, and recreational athletes with more therapeutic options.Measurement tools for mental toughness: Given the psychological components involved with these conditions, a tool to measure domains of sports mental toughness in athletes could help medical providers create a more comprehensive athlete profile which can be used in conjunction with standard pharmacologic therapy to provide a more effective treatment plan.Diagnosing DB: While normal breathing mechanics help shape appropriate posture and spinal stabilization, DB has been shown to contribute to pain and motor control deficits resulting in dysfunctional movement patterns, which further contribute to DB. Most respiratory specialists are unaware of how to assess the role of faulty sports technique, especially running gait, in dysfunctional breathing patterns making it difficult to recommend appropriate treatment and offer referrals for relevant therapies.Assessing postural changes: Three key components of proper running gait are reviewed and described in detail including trunk counter-rotation, extension of atlanto-occipital joint in conjunction with a forward tilted trunk, and ankle and hip joint range of motion.Conclusions: When underlying gait abnormalities and mental skills are addressed properly, they can disrupt poor breathing mechanics, facilitating a transition away from DB and toward healthier breathing patterns.KEY POINTS In summary, the following points should be considered when evaluating athletes who are having difficulty breathing even when compliant with their medications or if there is not an indication of asthma or EIB:Assess dysfunctional breathing (DB) with Nijmegen questionnaire (NQ).If DB is present, measure mental skills using the Sisu Quiz to determine an athlete's mental skills profile.Evaluate postural changes that may impact an athlete's ability to breathe.Using the three tools of the NQ, Sisu Quiz, and Postural assessments creates an athlete profile that is clinically useful to improve breathing technique.DB is often mistaken for other conditions for which medications are prescribed. By identifying DB early and making appropriate changes may negate or reduce the need for pharmacotherapy.Improving DB will improve athletic performance.

The Optimal Cut-off Score of the Nijmegen Questionnaire for Diagnosing Hyperventilation Syndrome Using a Bayesian Model in the Absence of a Gold Standard

Background

The Nijmegen questionnaire is one of the most common tools for diagnosing hyperventilation syndrome (HVS). However, there is no precise cut-off score for differentiating patients with HVS from those without HVS. This study was conducted to evaluate the accuracy of Nijmegen questionnaire for detecting patients with HVS and to provide the best cut-off score for differentiating patients with HVS from normal individuals using a Bayesian model in the absence of a gold standard.

Materials and Methods

A total of 490 students from a rehabilitation center in Tehran, Iran, were asked to participate in this case study of HVS from January to August 2018.

Results

A total of 215 students (40% male and 60% female) completed the Nijmegen questionnaire. The area under the receiver operating characteristic curve (AUC) was 0.93 (male: 0.95; female: 94) for all of the cut-off scores. The optimal cut-off score of ≥20 could predict HVS with sensitivity of 0.91 (male: 0.99; female: 91) and specificity of 0.92 (male: 96; female: 89).

Conclusion

Accurate differentiation of HVS patients from individuals without HVS can be accomplished by estimating the cut-off score of Nijmegen questionnaire based on a non-parametric Bayesian model.

Physical Activity: A Missing Link in Asthma Care

Asthma is the commonest respiratory disease and one of unceasingly increasing prevalence and burden. As such, asthma has attracted a major share or scientific interest and clinical attention. With the various clinical and pathophysiological aspects of asthma having been extensively investigated, the important association between asthma and physical activity remains underappreciated and insufficiently explored. Asthma impacts adversely on physical activity. Likewise, poor physical activity may lead to worse asthma outcomes. This concise clinical review presents the current recommendations for physical activity, discusses the available evidence on physical activity in asthma, and examines the causes of low physical activity in adult asthmatic patients. It also reviews the effect of daily physical activity and exercise training on the pathology and clinical outcomes of asthma. Finally, it summarizes the evidence on interventions targeting physical activity in asthma.

The impact of dysfunctional breathing on the level of asthma control in difficult asthma

BACKGROUND

Difficult asthma is defined as asthma requiring high dose treatment. However, systematic assessment is required to differentiate severe asthma from difficult-to-treat asthma. Dysfunctional breathing (DB) is a common comorbidity in difficult asthma, which may contribute to symptoms, but how it affects commonly used measures of symptom control is unclear.

METHODS

All adult asthma patients seen in four respiratory clinics over one year were screened prospectively, and patients with possible severe asthma according to ERS/ATS criteria ('Difficult asthma': high-dose inhaled corticosteroids/oral corticosteroids), underwent systematic assessment. Symptoms of DB were assessed utilizing a symptom based subjective tool, Nijmegen questionnaire (NQ), and objective signs of DB with the Breathing Pattern Assessment Tool (BPAT). Asthma control and quality of life were evaluated with the Asthma Control Questionnaire (ACQ) and the mini Asthma Quality of Life Questionnaire (AQLQ).

RESULTS

A total of 117 patients were included. Among these, 29.9% (35/117) had DB according to the NQ. Patients with DB had a poorer asthma control (ACQ: Mean (SD) 2.86 ± 1.05 vs. 1.46 ± 0.93) and lower quality of life (AQLQ score: Mean (SD) 4.2 ± 1.04 vs. 5.49 ± 0.85) compared to patients without DB. Similarly, patients with objective signs of DB according to the BPAT score had worse asthma control: BPAT >4 vs < 4: (ACQ: Mean (SD) 3.15 ± 0.93 vs 2.03 ± 1.15).

CONCLUSION

DB is common among patients with difficult asthma, and is associated with significantly poorer asthma control and lower quality of life. Assessment and treatment of DB is an important part of the management of difficult asthma.

Protocol for a multicentre randomised controlled trial to investigate the effect on asthma-related quality of life from breathing retraining in patients with incomplete asthma control attending specialist care in Denmark

INTRODUCTION AND AIM

Uncontrolled asthma is a global health challenge with substantial impact on quality of life (QoL) and overall healthcare costs. Unrecognised and/or unmanaged comorbidities often contribute to presence of uncontrolled asthma. Abnormalities in breathing pattern are termed dysfunctional breathing and are not only common in asthma but also lead to asthma-like symptoms and reduced QoL, and, in keeping with this, improvement with breathing normalisation. Evidence-based guidelines recommend breathing retraining interventions as an adjuvant treatment in uncontrolled asthma. Physiotherapy-based breathing pattern modification interventions incorporating relaxation have been shown to improve asthma-related QoL in primary care patients with impaired asthma control. Despite anecdotal reports, effectiveness of breathing retraining in patients referred to secondary care with incomplete asthma control has not been formally assessed in a randomised controlled trial (RCT). We aim to investigate the effect of breathing exercises on asthma-related QoL in patients with incomplete asthma control despite specialist care.

METHODS AND ANALYSIS

This two-armed assessor-blinded multicentre RCT will investigate the effect of physiotherapist-delivered breathing retraining on asthma QoL questionnaire (MiniAQLQ) in addition to usual specialist care, recruiting from seven outpatient departments and one specialised clinic representing all regions of Denmark during 2017-2019. We will include 190 consenting adults with incomplete asthma control, defined as Asthma Control Questionnaire 6-item score ≥0.8. Participants will randomly be allocated to either breathing exercise programme in addition to usual care (BrEX +UC) or UC alone. BrEX compiles three physiotherapy sessions and encouragement to perform home exercise daily. Both groups continue usual secondary care management. Primary outcome is between-group difference in MiniAQLQ at 6 months. Secondary outcomes include patient-reported outcome measures, spirometry and accelerometer.

ETHICS AND DISSEMINATION

Ethics Committee, Region Zealand (SJ-552) and Danish Data Protection Agency (REG-55-2016) approved the trial. Results will be reported in peer-reviewed scientific journals.

TRIAL REGISTRATION NUMBER

NCT03127059; Pre-results.

[Asthma and obesity in adults]

Asthma is a chronic inflammatory airway disorder characterized by a multitude of phenotypes. Epidemiological studies show an increase in asthma prevalence in obese patients regardless of age. The association of asthma and obesity is now considered as a phenotype with its own clinical, biological and functional characteristics. Regarding the pathophysiology of asthma and obesity, numerous factors such as nutrition, genetic predisposition, microbiome, ventilatory mechanics and the role of adipose tissue have been identified to explain the heterogeneous characteristics of patients with asthma and obesity. In adult patients with asthma and obesity, respiratory symptoms are particularly prominent and atopy and eosinophilic inflammation is uncommon compared to normal weight asthma patients. Obese asthma patients experience more hospitalizations and use more rescue medications than normal weight asthmatics. Management of asthma in obese patients is complex because these patients have less response to the usual anti-asthmatic treatments. Weight loss through caloric restriction combined with exercise is the main intervention to obtain improvement of asthma outcomes. Bariatric surgery is an invasive procedure with interesting results.

Dysfunctional breathing: what do we know?

Dysfunctional breathing (DB) is a respiratory condition characterized by irregular breathing patterns that occur either in the absence of concurrent diseases or secondary to cardiopulmonary diseases. Although the primary symptom is often dyspnea or “air hunger”, DB is also associated with nonrespiratory symptoms such as dizziness and palpitations. DB has been identified across all ages. Its prevalence among adults in primary care in the United Kingdom is approximately 9.5%. In addition, among individuals with asthma, a positive diagnosis of DB is found in a third of women and a fifth of men. Although DB has been investigated for decades, it remains poorly understood because of a paucity of high-quality clinical trials and validated outcome measures specific to this population. Accordingly, DB is often underdiagnosed or misdiagnosed, given the similarity of its associated symptoms (dyspnea, tachycardia, and dizziness) to those of other common cardiopulmonary diseases such as COPD and asthma. The high rates of misdiagnosis of DB suggest that health care professionals do not fully understand this condition and may therefore fail to provide patients with an appropriate treatment. Given the multifarious, psychophysiological nature of DB, a holistic, multidimensional assessment would seem the most appropriate way to enhance understanding and diagnostic accuracy. The present narrative review was developed as a means of summarizing the available evidence about DB, as well as improving understanding of the condition by researchers and practitioners.

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.

Factors Associated with Dysfunctional Breathing in Patients with Difficult to Treat Asthma

BACKGROUND

Understanding of dysfunctional breathing in patients with difficult asthma who remain symptomatic despite maximal inhaler therapy is limited.

OBJECTIVE

We characterized the pattern of dysfunctional breathing in patients with difficult asthma and identified possible contributory factors.

METHODS

Dysfunctional breathing was identified in patients with difficult asthma using the Nijmegen Questionnaire (score >23). Demographic characteristics, asthma variables, and comorbidities were assessed. Multivariate logistic regression was performed for dysfunctional breathing, adjusted for age, sex, body mass index, and airflow obstruction.

RESULTS

Of 157 patients with difficult asthma, 73 (47%) had dysfunctional breathing. Compared with patients without dysfunctional breathing, those with dysfunctional breathing experienced poorer asthma status (symptom control, quality of life, and exacerbation rates) and greater unemployment. In addition, more frequently they had elevated sino-nasal outcome test scores, anxiety, depression, sleep apnea, and gastroesophageal reflux. On multivariate analysis, anxiety (odds ratio [OR], 3.26; 95% CI, 1.18-9.01; P = .02), depression (OR, 2.8; 95% CI, 1.14-6.9; P = .03), and 22-item sino-nasal outcome test score (OR, 1.03; 95% CI, 1.003-1.05; P = .03) were independent risk factors for dysfunctional breathing.

CONCLUSIONS

Dysfunctional breathing is common in difficult asthma and associated with worse asthma status and unemployment. The independent association with psychological disorders and nasal obstruction highlight an important interaction between comorbid treatable traits in difficult asthma.

A proposed scheme to cope with comorbidities in asthma

The prevalence of non-communicable chronic diseases has been on the rise and the co-occurrence of morbidities is becoming more common. Multimorbidities are found more frequently among women, those with a history of mental disorders, lower level of schooling, and unfavorable socioeconomic condition. Physical inactivity, smoking and obesity are also associated with multimorbidities. Its occurrence is directly related to the age, affecting the majority of the individuals with more than 50 years old. It is important to consider the possibility of comorbid conditions that aggravate, complicate or simulate the symptoms of the disease in the face of a patient with asthma and poor response to treatment. Among subjects with asthma, some conditions stand out as the most frequent: chronic rhinitis or rhinosinusitis, gastroesophageal reflux disease, obstructive sleep apnea syndrome, obesity, and cardiovascular disorders. Comorbidities reduce the chances of optimal asthma control. It is essential to assess and manage properly these complex situations, choosing wisely preventive strategies and treatment options to avoid adverse events and optimize outcomes. Medications for asthma have the potential to worsen cardiovascular conditions, while beta-adrenergic receptor blockers and angiotensin conversion enzyme inhibitors used for cardiovascular conditions, can worsen asthma. Handling properly these cases will save lives and resources. However, there are multiple gaps in knowledge requiring investigation in this field to inform integrated care pathways and policies. It is likely information may be obtained from real life studies and electronic medical databases. Communications between the providers and patients may be facilitated by electronic technology, opening a large window for guided self-management.

Breathing training for dysfunctional breathing in asthma: taking a multidimensional approach

Various breathing training programmes may be helpful for adults with asthma. The main therapeutic aim for many of these programmes is the correction of dysfunctional breathing. Dysfunctional breathing can be viewed practically as a multidimensional entity with the three key dimensions being biochemical, biomechanical and psychophysiological. The objectives of this review are to explore how each of these dimensions might impact on asthma sufferers, to review how various breathing therapy protocols target these dimensions and to determine if there is evidence suggesting how breathing therapy protocols might be optimised. Databases and reference lists of articles were searched for peer-reviewed English language studies that discussed asthma or dysfunctional breathing and various breathing therapies. Biochemical, biomechanical and psychophysiological aspects of dysfunctional breathing can all potentially impact on asthma symptoms and breathing control. There is significant variation in breathing training protocols and the extent to which they evaluate and improve function in these three dimensions. The various dimensions of dysfunctional breathing may be of greater or lesser importance in different cases and the effectiveness of breathing training protocols is likely to be improved when all three dimensions are considered. Outcomes for breathing training for dysfunctional breathing in asthma may be most successful when the three key dimensions of dysfunctional breathing are evaluated at the start of treatment and monitored during treatment. This allows breathing training protocols to be adjusted as appropriate to ensure that treatment is sufficiently comprehensive and intensive to produce measurable improvements where necessary.

Mechanisms, measurement and management of exertional dyspnoea in asthma: Number 5 in the Series "Exertional dyspnoea" Edited by Pierantonio Laveneziana and Piergiuseppe Agostoni

Asthma is a heterogeneous condition, with dyspnoea during exercise affecting individuals to a variable degree. This narrative review explores the mechanisms and measurement of exertional dyspnoea in asthma and summarises the available evidence for the efficacy of various interventions on exertional dyspnoea. Studies on the mechanisms of dyspnoea in asthma have largely utilised direct bronchoprovocation challenges, rather than exercise, which may invoke different physiological mechanisms. Thus, the description of dyspnoea during methacholine challenge can differ from what is experienced during daily activities, including exercise. Dyspnoea perception during exercise is influenced by many interacting variables, such as asthma severity and phenotype, bronchoconstriction, dynamic hyperinflation, respiratory drive and psychological factors. In addition to the intensity of dyspnoea, the qualitative description of dyspnoea may give important clues as to the underlying mechanism and may be an important endpoint for future interventional studies. There is currently little evidence demonstrating whether pharmacological or non-pharmacological interventions specifically improve exertional dyspnoea, which is an important area for future research.

Advances in the Evaluation of Respiratory Pathophysiology during Exercise in Chronic Lung Diseases

Dyspnea and exercise limitation are among the most common symptoms experienced by patients with various chronic lung diseases and are linked to poor quality of life. Our understanding of the source and nature of perceived respiratory discomfort and exercise intolerance in chronic lung diseases has increased substantially in recent years. These new mechanistic insights are the primary focus of the current review. Cardiopulmonary exercise testing (CPET) provides a unique opportunity to objectively evaluate the ability of the respiratory system to respond to imposed incremental physiological stress. In addition to measuring aerobic capacity and quantifying an individual's cardiac and ventilatory reserves, we have expanded the role of CPET to include evaluation of symptom intensity, together with a simple "non-invasive" assessment of relevant ventilatory control parameters and dynamic respiratory mechanics during standardized incremental tests to tolerance. This review explores the application of the new advances in the clinical evaluation of the pathophysiology of exercise intolerance in chronic obstructive pulmonary disease (COPD), chronic asthma, interstitial lung disease (ILD) and pulmonary arterial hypertension (PAH). We hope to demonstrate how this novel approach to CPET interpretation, which includes a quantification of activity-related dyspnea and evaluation of its underlying mechanisms, enhances our ability to meaningfully intervene to improve quality of life in these pathologically-distinct conditions.

The impact of dysfunctional breathing on the assessment of asthma control

BACKGROUND AND OBJECTIVE

Dysfunctional breathing (DB) is a respiratory disorder, which involves a pattern of breathing too deeply, too superficially and/or too rapidly. In asthma patients, DB may lead to an overestimation of the severity of asthma symptoms, and hence potentially to overtreatment. However, it is not known to which degree DB may affect estimates of asthma control, in a specialist clinical setting.

METHODS

The MAPOut-study examined all patients referred consecutively over a 12-months period for specialist assessment of asthma at the Respiratory Outpatient Clinic at Bispebjerg Hospital in Copenhagen. All patients were examined with the Nijmegen questionnaire with a DB defined as a score ≥23 and the ACQ questionnaire. Linear regression analysis of predictors of ACQ score was performed. Asthma was defined as asthma symptoms and a positive asthma test.

RESULTS

Of the 256 patients referred to the lung clinic, data on both the Nijmegen questionnaire and ACQ score was obtained in 127 patients, who were included in the present analysis. Median (range) age: 30 (15-63) years, and 76 (59.8%) were females. DB was found in 31 (24.4%). Asthmatic patients with co-existing DB had a poorer asthma control compared to asthmatics without DB (Median (range) ACQ score: 2.40 (0.20-4.60) vs 1.20 (0.00-4.40); p < 0.001.). A regression analysis showed that the effect of DB on asthma control was independent of airway hyperresponsiveness or airway inflammation in patients with DB.

CONCLUSION

Dysfunctional breathing is common among asthma patients in a specialist setting, and results in a clinically significant underestimation of asthma control, which may potentially lead to overtreatment.

Abnormal vocal cord movement in patients with and without airway obstruction and asthma symptoms

BACKGROUND

Abnormal vocal cord movements can cause laryngeal extrathoracic airway obstruction (often called vocal cord dysfunction - VCD) leading to asthma-like symptoms. These aberrant movements are characteristically present during inspiration and termed paradoxical vocal cord movement (PVCM). We have reported PVCM in up to 40% of severe asthmatics, but it is not known if PVCM is detectable in all patients with asthma-like symptoms and if the condition is more often associated with abnormal lung function.

OBJECTIVE

We hypothesized that PVCM is frequently associated with asthma symptoms accompanied by airflow limitation. Studies examined whether PVCM is solely linked to experiencing asthma symptoms, or if PVCM is related to airflow limitation and/or other disease characteristics.

METHODS

Patients with asthma symptoms were recruited from general practice and severe asthma clinics (n = 155). Pulmonary function measurements were conducted, asthma control and Nijmegen (dysfunctional breathing) questionnaires were administered and skin prick testing was carried out. PVCM was quantified using dynamic 320-slice computerized tomography of the larynx. Groups were divided into patients with FEV₁ ≥ 80% predicted or FEV₁ < 80% predicted and FEV₁ /FVC < 0.7. ATS/ERS definitions of severity were also applied and evaluated. Detection of PVCM in the groups was compared and analyses performed to identify features associated with PVCM.

RESULTS

Overall (n = 155), PVCM was detected in 42 cases (27.1%). Patients with FEV₁ < 80% predicted had PVCM more often (25/68, 36.8%) than individuals with normal spirometry (17/87, 19.5%; P = 0.016). PVCM was associated with older age (P = 0.003) and with Nijmegen scores > 20 (P = 0.04). Patients with FEV₁ < 80% predicted plus Nijmegen scores > 20 were more likely to have PVCM (OR = 9.3, P = 0.02).

CONCLUSIONS AND CLINICAL RELEVANCE

Paradoxical vocal cord movement is more often associated with asthma symptoms accompanied by airflow limitation and dysfunctional breathing. Further studies are needed to determine whether PVCM is induced by dysfunctional breathing practices and/or airway obstruction. How PVCM links with symptomatic asthma and VCD also requires evaluation.

Dysfunctional breathing: a review of the literature and proposal for classification

Dysfunctional breathing is a term describing breathing disorders where chronic changes in breathing pattern result in dyspnoea and other symptoms in the absence or in excess of the magnitude of physiological respiratory or cardiac disease. We reviewed the literature and propose a classification system for the common dysfunctional breathing patterns described. The literature was searched using the terms: dysfunctional breathing, hyperventilation, Nijmegen questionnaire and thoraco-abdominal asynchrony. We have summarised the presentation, assessment and treatment of dysfunctional breathing, and propose that the following system be used for classification. 1) Hyperventilation syndrome: associated with symptoms both related to respiratory alkalosis and independent of hypocapnia. 2) Periodic deep sighing: frequent sighing with an irregular breathing pattern. 3) Thoracic dominant breathing: can often manifest in somatic disease, if occurring without disease it may be considered dysfunctional and results in dyspnoea. 4) Forced abdominal expiration: these patients utilise inappropriate and excessive abdominal muscle contraction to aid expiration. 5) Thoraco-abdominal asynchrony: where there is delay between rib cage and abdominal contraction resulting in ineffective breathing mechanics.

This review highlights the common abnormalities, current diagnostic methods and therapeutic implications in dysfunctional breathing. Future work should aim to further investigate the prevalence, clinical associations and treatment of these presentations.

Diagnosis and investigation in the severe asthma clinic

Severe asthma is recognised as an important and emerging area of unmet need in asthma. The assessment of severe asthma should include three steps; (1) determining the diagnosis of asthma, including verification that the disease is severe asthma, (2) assessing comorbidities and contributing factors that will impact on clinical severity, as well as (3) assessing asthma phenotypes. These steps recognize the importance of heterogeneity in asthma as a key factor that determines the disease course and increasingly the choice of successful therapy. This assessment should be undertaken systematically and is best done by an expert multidisciplinary team. Here, we will outline the important aspects that should be included in the clinical assessment of the patient in the severe asthma clinic, including diagnosis, clinical history, the assessment of important comorbidities and the key investigations needed to support them.

Cramps and tingling: A diagnostic conundrum

Tetany a syndrome of sharp flexion of the wrist and ankle joints (carpopedal spasm), muscle twitching, cramps and convulsions, sometimes with an attack of stridor, is due to hyperexcitability of nerves and muscles caused by decreased extracellular ionized calcium. Hyperventilation secondary to anxiety can result in tetany. We report a case of hyperventilation induced tetany 2 h following spinal anesthesia for inguinal hernia repair.

Hyperventilation in asthma: a validation study of the Nijmegen Questionnaire--NQ

INTRODUCTION

The Nijmegen questionnaire (NQ) has previously been used for screening the hyperventilation syndrome (HVS) in asthmatics. However, no validity study has been reported so far.

OBJECTIVE

To examine the validity and reliability of the NQ in asthma patients and identify the prevalence of HVS.

METHODS

The NQ (n = 162) was examined for translation, construct, cross-sectional and discriminant validity as well as for internal consistency and test-retest reliability.

RESULTS

Principal component analysis and exploratory factor analysis revealed a single factor solution with 11 items and 58.6% of explained variability. These 11 NQ items showed high internal consistency (Cronbach's alpha = 0.92) and test-retest reliability (IR = 0.98). Higher NQ scores were found in the following subgroups: women versus men (p < 0.01); participants with moderate versus mild asthma (p < 0.001) or uncontrolled versus controlled asthma (p < 0.001), and participants with breath-hold time (BHT) < 30 versus ≥ 30 s (p < 0.01) or end-tidal CO2 (ETCO2) ≤ 35 versus >35 mmHg (p < 0.001). A cut-off score of >17 discriminated the participants with regard to the presence of HVS. The NQ showed 92.73% sensitivity and 91.59% specificity. The total NQ score was found significantly correlated with ETCO2 (r = -0.68), RR (r = 0.66) and BHT (r = -0.65). The prevalence of HVS was found 34%.

CONCLUSION

The NQ is a valid and reliable questionnaire for screening HVS in patients with stable mild-to-moderate asthma.

Is there an association between postural balance and pulmonary function in adults with asthma?

OBJECTIVE

Asthma may cause systemic repercussions due to its severity and the effects of treatment. Our objective was to compare posture, balance, functional capacity, and quality of life (QOL) according to the severity of disease, as assessed by pulmonary function levels.

METHOD

This cross-sectional study evaluated fifty individuals with asthma. We compared two groups of adult individuals who were divided according to the median of the forced expiratory volume in one second (FEV1) as follows: group A  =  FEV1>74% predicted; group B  =  FEV1<74% predicted. All patients underwent the following tests: spirometry, whole-body plethysmography, diffusing capacity for carbon monoxide (DLco), respiratory muscle strength, posture assessment, stabilometry, six-minute walking distance (6MWD), and QOL.

RESULTS

All pulmonary function variables exhibited statistically significant differences between the two groups, except for the DLco. The maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), and 6MWD were lower in group B. The maximal mediolateral velocity and the mediolateral displacement were significantly different, while the postural changes and QOL were similar between the groups.

CONCLUSIONS

In adult individuals with asthma, the pulmonary function is associated with balance control in the mediolateral direction but does not influence the postural changes or QOL.

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.