An observational investigation of dysfunctional breathing and breathing control therapy in a problem asthma clinic

[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.

[Hyperventilation syndrome, definition, diagnostic and therapy]

Hyperventilation syndrome (HVS) is a frequent disorder of which the etiology is unclear. Diagnosis is based on the ruling out of organic disease and, more positively, on results of the Nijmegen questionnaire, reproduction of symptoms during the hyperventilation provocation test (HPVT), and detected hypocapnia. Treatment is based on targeted respiratory physiotherapy consisting in voluntary hypoventilation and instructions to the patient on regular respiratory exercise over an appreciable period of time. Additional research is needed to evaluate the validity of current investigative tools leading to the diagnosis of hyperventilation syndrome and to appraise the efficacy of current respiratory physiotherapy methods.

Dysfunctional breathing and its impact on asthma control in children and adolescents

BACKGROUND

Dysfunctional breathing (DB) has been shown to negatively affect asthma control in adults, but for children and adolescents, the knowledge is scarce. DB is among others characterized by dyspnea and hyperventilation. The Nijmegen Questionnaire (NQ) is often used as a marker for DB. We conducted a cross-sectional survey to estimate the prevalence of DB in patients with asthma in a pediatric outpatient clinic and to determine the impact of DB on asthma control.

METHODS

Patients between 10 and 17 years were invited to complete the NQ and the Asthma Control Questionnaire (ACQ) and report the use of beta2 agonist (β2). Spirometry data and prescribed asthma medications were noted from the patient record.

RESULTS

Three hundred and sixty-three patients (180 boys) completed the survey. Sixty-seven patients (18%) scored ≥23 points in the NQ predicting DB. The DB group was older (median (range)) 15.6 (10.5-17.9) vs. 13.7 (10.0-17.9) years) (p < .01), and girls were overrepresented (84%) (p < .01). FEV1% exp. was higher in the DB group (mean (SD)) (89.4 (9.0) vs. 85.7 (11.8)) (p < .02). ACQ score (median (range)) (2.0 (0-4) vs. 0.6 (0-3.4)) (p < .01) and the use of β2 (median (range)) (2 (0-56) vs. 0 (0-20) puffs/week) (p < .01) were higher. Inhaled corticosteroid dose (mean (SD) (416 (160) vs. 420 (150) mcg) and the use of a second controller were equal between the groups.

CONCLUSION

Dysfunctional breathing was a frequent comorbidity, especially in adolescent girls. DB correlated with poorer asthma control and higher use of β2 and may be an important cofactor in difficult-to-treat asthma.

Breathing Pattern Disorders Distinguished from Healthy Breathing Patterns Using Optoelectronic Plethysmography

There is no gold standard diagnostic method for breathing pattern disorders (BPD) which is commonly diagnosed through the exclusion of other pathologies. Optoelectronic plethysmography (OEP) is a 3D motion capture technique that provides a comprehensive noninvasive assessment of chest wall during rest and exercise. The purpose of this study was to determine if OEP can distinguish between active individuals classified with and without BPD at rest and during exercise. Forty-seven individuals with a healthy breathing pattern (HBP) and twenty-six individuals with a BPD performed a submaximal exercise challenge. OEP measured the movement of the chest wall through the calculation of timing, percentage contribution, and phase angle breathing pattern variables. A mixed model repeated measures ANOVA analysed the OEP variables between the groups classified as HBP and BPD at rest, during exercise, and after recovery. At rest, regional contribution variables including ribcage percentage contribution (HBP: 71% and BPD: 69%), abdominal ribcage contribution (HBP: 13% and BPD: 11%), abdomen percentage contribution (HBP: 29% and BPD: 31%), and ribcage and abdomen volume index (HPB: 2.5 and BPD: 2.2) were significantly (p < 0.05) different between groups. During exercise, BPD displayed significantly (p < 0.05) more asynchrony between various thoracic compartments including the ribcage and abdomen phase angle (HBP: -1.9 and BPD: -2.7), pulmonary ribcage and abdomen phase angle (HBP: -0.5 and BPD, 0.5), abdominal ribcage and shoulders phase angle (HBP: -0.3 and BPD: 0.6), and pulmonary ribcage and shoulders phase angle (HBP: 0.2 and BPD: 0.6). Additionally, the novel variables inhale deviation (HBP: 8.8% and BPD: 19.7%) and exhale deviation (HBP: -10.9% and BPD: -17.6%) were also significantly (p < 0.05) different between the groups during high intensity exercise. Regional contribution and phase angles measured via OEP can distinguish BPD from HBP at rest and during exercise. Characteristics of BPD include asynchronous and thoracic dominant breathing patterns that could form part of future objective criteria for the diagnosis of BPD.

Type 2 inflammation in asthma and other airway diseases

Chronic inflammatory airway diseases, including asthma, chronic rhinosinusitis, eosinophilic COPD and allergic rhinitis are a global health concern. Despite the coexistence of these diseases and their common pathophysiology, they are often managed independently, resulting in poor asthma control, continued symptoms and poor quality of life. Understanding disease pathophysiology is important for best treatment practice, reduced disease burden and improved patient outcomes. The pathophysiology of type 2 inflammation is driven by both the innate immune system triggered by pollutants, viral or fungal infections involving type 2 innate lymphoid cells (ILC2) and the adaptive immune system, triggered by contact with an allergen involving type 2 T-helper (Th2) cells. Both ILC2 and Th2 cells produce the type-2 cytokines (interleukin (IL)-4, IL-5 and IL-13), each with several roles in the inflammation cascade. IL-4 and IL-13 cause B-cell class switching and IgE production, release of pro-inflammatory mediators, barrier disruption and tissue remodelling. In addition, IL-13 causes goblet-cell hyperplasia and mucus production. All three interleukins are involved in trafficking eosinophils to tissues, producing clinical symptoms characteristic of chronic inflammatory airway diseases. Asthma is a heterogenous disease; therefore, identification of biomarkers and early targeted treatment is critical for patients inadequately managed by inhaled corticosteroids and long-acting β-agonists alone. The Global Initiative for Asthma guidelines recommend add-on biological (anti IgE, IL-5/5R, IL-4R) treatments for those not responding to standard of care. Targeted therapies, including omalizumab, mepolizumab, reslizumab, benralizumab, dupilumab and tezepelumab, were developed on current understanding of the pathophysiology of type 2 inflammation. These therapies offer hope for improved management of type 2 inflammatory airway diseases.

2021 Brazilian Thoracic Association recommendations for the management of severe asthma

Advances in the understanding that severe asthma is a complex and heterogeneous disease and in the knowledge of the pathophysiology of asthma, with the identification of different phenotypes and endotypes, have allowed new approaches for the diagnosis and characterization of the disease and have resulted in relevant changes in pharmacological management. In this context, the definition of severe asthma has been established, being differentiated from difficult-to-control asthma. These recommendations address this topic and review advances in phenotyping, use of biomarkers, and new treatments for severe asthma. Emphasis is given to topics regarding personalized management of the patient and selection of biologicals, as well as the importance of evaluating the response to treatment. These recommendations apply to adults and children with severe asthma and are targeted at physicians involved in asthma treatment. A panel of 17 Brazilian pulmonologists was invited to review recent evidence on the diagnosis and management of severe asthma, adapting it to the Brazilian reality. Each of the experts was responsible for reviewing a topic or question relevant to the topic. In a second phase, four experts discussed and structured the texts produced, and, in the last phase, all experts reviewed and approved the present manuscript and its recommendations.

Minute ventilation/carbon dioxide production in patients with dysfunctional breathing

Dysfunctional breathing refers to a multi-dimensional condition that is characterised by pathological changes in an individual's breathing. These changes lead to a feeling of breathlessness and include alterations in the biomechanical, psychological and physiological aspects of breathing. This makes dysfunctional breathing a hard condition to diagnose, given the diversity of aspects that contribute to the feeling of breathlessness. The disorder can debilitate individuals without any health problems, but may also be present in those with underlying cardiopulmonary co-morbidities. The ventilatory equivalent for CO₂ (V _eqCO2 ) is a physiological parameter that can be measured using cardiopulmonary exercise testing. This review will explore how this single measurement can be used to aid the diagnosis of dysfunctional breathing. A background discussion about dysfunctional breathing will allow readers to comprehend its multidimensional aspects. This will then allow readers to understand how V _eqCO2 can be used in the wider diagnosis of dysfunctional breathing. Whilst V _eqCO2 cannot be used as a singular parameter in the diagnosis of dysfunctional breathing, this review supports its use within a broader algorithm to detect physiological abnormalities in patients with dysfunctional breathing. This will allow for more individuals to be accurately diagnosed and appropriately managed.

[Physical activity and pulmonary rehabilitation in adults with asthma]

Physical activity is reduced in people with asthma compared to the general population, especially in situations where patients have uncontrolled asthma symptoms, persistent airflow obstruction and other long-term medical problems, in particular obesity and anxiety. Exertional dyspnea, which is of multifactorial origin, is the main cause of reduced physical activity reduction and draws patients into a vicious circle further impairing quality of life and asthma control. Both the resumption of a regular physical activity, integrated into daily life, adapted to patients' needs and wishes as well as physical and environmental possibilities for mild to moderate asthmatics, and pulmonary rehabilitation (PR) for severe and/or uncontrolled asthmatics, improve control of asthma, dyspnea, exercise tolerance, quality of life, anxiety, depression and reduce exacerbations. A motivational interview to promote a regular programme of physical activity in mild to moderate asthma (steps 1 to 3) should be offered by all health professionals in the patient care pathway, within the more general framework of therapeutic education. The medical prescription of physical activities, listed in the Public Health Code for patients with long-term diseases, and pulmonary rehabilitation should be performed more often by specialists or the attending physician. Pulmonary rehabilitation addresses the needs of severe asthma patients (steps 4 and 5), and of any asthmatic patient with poorly controlled disease and/or requiring hospitalized for acute exacerbations, regardless of the level of airflow obstruction, and/or with associated comorbidities, and before prescribing biological therapies.

The impact of comorbidities on severe asthma

PURPOSE OF REVIEW

Severe asthma is often associated with numerous comorbidities that complicate disease management and affect patient's outcomes. They contribute to poor disease control and mimic asthma symptoms. Although some comorbidities such as obstructive sleep apnea, bronchiectasis, and chronic obstructive pulmonary disease are generally well recognized, many other may remain undiagnosed but may be detected in an expert specialist setting. The management of comorbidities seems to improve asthma outcomes, and optimizes therapy by avoiding overtreatment. The present review provides recent knowledge regarding the most common comorbidities which are associated with severe asthma.

RECENT FINDINGS

Comorbidities are more prevalent in severe asthma than in mild-to-moderate disease or in the general population. They can be grouped into two large domains: the pulmonary domain and the extrapulmonary domain. Pulmonary comorbidities include upper respiratory tract disorders (obstructive sleep apnea, allergic and nonallergic rhinitis, chronic rhinosinusitis, nasal polyposis) and middle/lower respiratory tract disorders (chronic obstructive pulmonary disease, allergic bronchopulmonary aspergillosis and fungal sensitization, bronchiectasis, dysfunctional breathing). Extrapulmonary comorbidities include anxiety, depression, gastro-esophageal reflux disease, obesity, cardiovascular, and metabolic diseases.

SUMMARY

The identification of comorbidities via multidimensional approach is needed to initiate appropriate multidisciplinary management of patients with severe asthma.

Cardiopulmonary Exercise Testing in the Assessment of Dysfunctional Breathing

Dysfunctional breathing (DB) is a disabling condition which affects the biomechanical breathing pattern and is challenging to diagnose. It affects individuals in many circumstances, including those without underlying disease who may even be athletic in nature. DB can also aggravate the symptoms of those with established heart or lung conditions. However, it is treatable and individuals have much to gain if it is recognized appropriately. Here we consider the role of cardiopulmonary exercise testing (CPET) in the identification and management of DB. Specifically, we have described the diagnostic criteria and presenting symptoms. We explored the physiology and pathophysiology of DB and physiological consequences in the context of exercise. We have provided examples of its interplay with co-morbidity in other chronic diseases such as asthma, pulmonary hypertension and left heart disease. We have discussed the problems with the current methods of diagnosis and proposed how CPET could improve this. We have provided guidance on how CPET can be used for diagnosis, including consideration of pattern recognition and use of specific data panels. We have considered categorization, e.g., predominant breathing pattern disorder or acute or chronic hyperventilation. We have explored the distinction from gas exchange or ventilation/perfusion abnormalities and described other potential pitfalls, such as false positives and periodic breathing. We have also illustrated an example of a clinical pathway utilizing CPET in the diagnosis and treatment of individuals with suspected DB.

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.

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.

Diagnosis of severe asthma

Patients with asthma that is uncontrolled despite high intensity medication can present in both primary and specialist care. An increasing number of novel (and expensive) treatments are available for patients who fail conventional asthma therapy, but these may not be appropriate for all such patients. It is essential that a rigorous evaluation process be undertaken for these patients to identify those with biologically severe asthma who will require novel therapies, and those who may improve with control of contributory factors. In this article, we describe three key steps in the diagnostic evaluation process for severe asthma. The first step is confirmation of asthma diagnosis with objective evidence of variable airflow obstruction. The second involves management of contributory factors such as non-adherence, poor inhaler technique, ongoing asthma triggers, and comorbidities. The third step involves phenotyping and endotyping of patients with severe asthma. We provide a practical approach to implementing these measures in both primary and secondary care.

[Role of non pharmacological Interventions for asthma]

Smoking cessation remains a major issue for asthmatic smokers. Respiratory rehabilitation and respiratory physiotherapy have shown a benefit in controlling symptoms, preventing exacerbations and improving the quality of life. The control of the environment is crucial and must be approached in a global way. Management of obesity and psychological disorders should be systematically proposed. Allergen immunotherapy may be discussed in allergic persistent asthma to house dust mites. Certain dietary interventions or alternative medicines have not proved their worth.

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.

Comorbid "treatable traits" in difficult asthma: Current evidence and clinical evaluation

The care of patients with difficult-to-control asthma ("difficult asthma") is challenging and costly. Despite high-intensity asthma treatment, these patients experience poor asthma control and face the greatest risk of asthma morbidity and mortality. Poor asthma control is often driven by severe asthma biology, which has appropriately been the focus of intense research and phenotype-driven therapies. However, it is increasingly apparent that extra-pulmonary comorbidities also contribute substantially to poor asthma control and a heightened disease burden. These comorbidities have been proposed as "treatable traits" in chronic airways disease, adding impetus to their evaluation and management in difficult asthma. In this review, eight major asthma-related comorbidities are discussed: rhinitis, chronic rhinosinusitis, gastroesophageal reflux, obstructive sleep apnoea, vocal cord dysfunction, obesity, dysfunctional breathing and anxiety/depression. We describe the prevalence, impact and treatment effects of these comorbidities in the difficult asthma population, emphasizing gaps in the current literature. We examine the associations between individual comorbidities and highlight the potential for comorbidity clusters to exert combined effects on asthma outcomes. We conclude by outlining a pragmatic clinical approach to assess comorbidities in difficult asthma.

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.

Novel assessment tool to detect breathing pattern disorder in patients with refractory asthma

BACKGROUND AND OBJECTIVE

Breathing pattern disorder (BPD) can co-exist with and mimic asthma, acting to amplify symptoms and confound assessment of disease control, resulting in inappropriate treatment escalation. The aim of this research was to report the utility of a novel breathing pattern assessment tool (BPAT) to detect BPD in treatment-refractory asthma.

METHODS

As a component of a multidisciplinary assessment, adult patients referred with treatment-refractory asthma underwent respiratory physiotherapy assessment to diagnose BPD. Based on this assessment, patients were classified as having asthma, asthma + BPD or BPD alone. BPAT data were collected in addition to questionnaire data (Asthma Quality of Life Questionnaire (AQLQ) and Nijmegen Questionnaire (NQ)), pulmonary function and an assessment of exercise capacity.

RESULTS

Data were retrospectively analysed for 150 (female; 69%) patients, mean (SD) age of 43 (14) years; characterized as asthma-only (n = 54, 36%), asthma + BPD (n = 63, 42%) and BPD-only (n = 33, 22%). Of the total population, 113 (76%) had an NQ score ≥23, but of these only 68% had physiotherapy evidence of BPD. Exercise capacity and AQLQ were lower in the asthma + BPD group than in the asthma-only group (P < 0.05), whilst lung function was similar between groups. Sensitivity analysis indicated that a BPAT score of ≥4 corresponded to a sensitivity of 0.92 and a specificity of 0.75 for diagnosis of BPD in this cohort.

CONCLUSION

Breathing pattern irregularities are highly prevalent in individuals referred with treatment-refractory asthma and can be characterized using the BPAT. Further work is needed to determine inter-observer and within-subject variability and ensure the BPAT is a robust clinical tool. Watch the video abstract.

Dysfunctional breathing is more frequent in chronic obstructive pulmonary disease than in asthma and in health

Involuntary adaptations of breathing patterns to counter breathlessness may lead to dysfunctional breathing in obstructive lung diseases. However, no studies examining dysfunctional breathing in Chronic Obstructive Pulmonary Disease (COPD) have been reported. Patients with verified COPD (n=34), asthma (n=37) and a healthy control group (n=41) were recruited. All participants completed the Nijmegen questionnaire for dysfunctional breathing as well as measures of disease activity. Comparisons between groups employed analysis of variance with post-hoc Bonferroni analyses and Pearson correlation for associations. Patients with COPD had significantly higher Nijmegen questionnaire scores than asthmatics (COPD: 23.4±10.6 versus 17.3±10.6, p=0.016) and healthy individuals (14.3±9.6, p=0.002). Significantly more patients with COPD had severe dysfunctional breathing with Nijmegen scores >23 (47%; 16/34) compared to asthma (27%; 10/37) and healthy controls (17%; 7/41) respectively (p=0.019). Dysfunctional breathing was detected in ∼50% of patients with COPD, more so than in asthma or health. Strategies to reduce abnormal breathing behaviours may have important benefits for treatment of breathlessness in COPD.

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.

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.

Getting to grips with 'dysfunctional breathing'

Dysfunctional breathing (DB) is common, frequently unrecognised and responsible for a substantial burden of morbidity. Previously lack of clarity in the use of the term and the use of multiple terms to describe the same condition has hampered our understanding. DB can be defined as an alteration in the normal biomechanical patterns of breathing that result in intermittent or chronic symptoms. It can be subdivided into thoracic and extra thoracic forms. Thoracic DB is characterised by breathing patterns involving relatively inefficient, excessive upper chest wall activity with or without accessory muscle activity. This is frequently associated with increased residual volume, frequent sighing and an irregular pattern of respiratory effort. It may be accompanied by true hyperventilation in the minority of subjects. Extra thoracic forms include paradoxical vocal cord dysfunction and the increasingly recognised supra-glottic 'laryngomalacia' commonly seen in young sportsmen and women. While the two forms would appear to be two discreet entities they often share common factors in aetiology and respond to similar interventions. Hence both forms are considered in this review which aims to generate a more coherent approach to understanding, diagnosing and treating these conditions.

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.

Breathing exercises for dysfunctional breathing/hyperventilation syndrome in children

BACKGROUND

Dysfunctional breathing is described as chronic or recurrent changes in breathing pattern causing respiratory and non-respiratory symptoms. It is an umbrella term that encompasses hyperventilation syndrome and vocal cord dysfunction. Dysfunctional breathing affects 10% of the general population. Symptoms include dyspnoea, chest tightness, sighing and chest pain which arise secondary to alterations in respiratory pattern and rate. Little is known about dysfunctional breathing in children. Preliminary data suggest 5.3% or more of children with asthma have dysfunctional breathing and that, unlike in adults, it is associated with poorer asthma control. It is not known what proportion of the general paediatric population is affected. Breathing training is recommended as a first-line treatment for adults with dysfunctional breathing (with or without asthma) but no similar recommendations are available for the management of children. As such, breathing retraining is adapted from adult regimens based on the age and ability of the child.

OBJECTIVES

To determine whether breathing retraining in children with dysfunctional breathing has beneficial effects as measured by quality of life indices.To determine whether there are any adverse effects of breathing retraining in young people with dysfunctional breathing.

SEARCH METHODS

We identified trials for consideration using both electronic and manual search strategies. We searched CENTRAL, MEDLINE and EMBASE. We searched the National Research Register (NRR) Archive, Health Services Research Projects in Progress (HSRProj), Current Controlled Trials register (incorporating the metaRegister of Controlled Trials and the International Standard Randomised Controlled Trial Number (ISRCTN) to identify research in progress and unpublished research. The latest search was undertaken in October 2013.

SELECTION CRITERIA

We planned to include randomised, quasi-randomised or cluster-randomised controlled trials. We excluded observational studies, case studies and studies utilising a cross-over design. The cross-over design was considered inappropriate due to the purported long-lasting effects of breathing retraining. Children up to the age of 18 years with a clinical diagnosis of dysfunctional breathing were eligible for inclusion. We planned to include children with a primary diagnosis of asthma with the intention of undertaking a subgroup analysis. Children with symptoms secondary to cardiac or metabolic disease were excluded.We considered any type of breathing retraining exercise for inclusion in this review, such as breathing control, diaphragmatic breathing, yoga breathing, Buteyko breathing, biofeedback-guided breathing modification and yawn/sigh suppression. We considered programmes where exercises were either supervised (by parents or a health professional, or both) or unsupervised. We also considered relaxation techniques and acute episode management as long as it was clear that breathing exercises were a component of the intervention.Any intervention without breathing exercises or where breathing exercises were not key to the intervention were excluded.

DATA COLLECTION AND ANALYSIS

We planned that two authors (NJB and MJ) would extract data independently using a standardised form. Any discrepancies would be resolved by consensus. Where agreement could not be reached a third review author (MLE) would have considered the paper.

MAIN RESULTS

We identified 264 potential trials and reviews from the search. Following removal of duplicates, we screened 224 papers based on title and abstract. We retrieved six full-text papers and further evaluated them but they did not meet the inclusion criteria. There were, therefore, no studies suitable for inclusion in this review.

AUTHORS' CONCLUSIONS

The results of this systematic review cannot inform clinical practice as no suitable trials were identified for inclusion. Therefore, it is currently unknown whether these interventions offer any added value in this patient group or whether specific types of breathing exercise demonstrate superiority over others. Given that breathing exercises are frequently used to treat dysfunctional breathing/hyperventilation syndrome, there is an urgent need for well-designed clinical trials in this area. Future trials should conform to the CONSORT statement for standards of reporting and use validated outcome measures. Trial reports should also ensure full disclosure of data for all important clinical outcomes.

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.

Pulmonary physiotherapy in patients with bronchial asthma

In the present study we investigated the effectiveness of a 3-month breathing exercise program in patients with mild-to-moderate asthma, as assessed from spirometric indices. The study group consisted of 28 asthma patients (mean age of 43 years). The physiotherapy program consisted of 45-min exercise sessions, performed twice a week for 3 months. We measured the flow-volume indices (FEV(1), FVC, PEF, MEF(50)) before and after the exercise sessions at the beginning and end of the physiotherapy program. In addition, the patients measured their personal best peak expiratory flow (PEF). We found no significant changes in spirometric indices before and after an exercise session either at the beginning or end of the physiotherapy program, although there was a tendency for lower values after the exercise sessions at both beginning and end of the physiotherapy program. There was a significant decrease in PEF after an exercise session at the beginning of the physiotherapy program; this decrease lost significance after completion of the physiotherapy program. However, PEF values were greater both before and after the exercise sessions at the end of the physiotherapy program compared with the corresponding sessions before the program. We conclude that the breathing exercise program employed in the study failed to appreciably improve lung function in asthmatic patients. However, there was no asthma exacerbations observed during the conduction of breathing exercise program, which underscores the need for pulmonary rehabilitation in asthma treatment.

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

Background

Abnormal breathing patterns may cause characteristic symptoms and impair quality of life. In a cross-sectional survey 29% of adults treated for asthma in primary care had symptoms suggestive of dysfunctional breathing (DB), more likely to be female and younger, with no differences for severity of asthma. No clear risk factors were demonstrated for DB in asthma, nor the impact of asthma medication was evaluated. The objective of this study was to describe the DB phenotype in adults with asthma treated in a specialised asthma centre.

Methods

Adult patients aged 17–65 with diagnosed asthma were screened for DB using the Nijmegen questionnaire (positive predictive score >23) and confirmed by progressive exercise testing. The following were evaluated as independent risk factors for DB in the multiple regression analysis: female sex; atopy, obesity, active smoker, moderate/severe rhinitis, psychopathology, GERD, arterial hypertension; severe asthma, asthma duration > 5 years, lack of asthma control, fixed airway obstruction, fast lung function decline, frequent exacerbator and brittle asthma phenotypes; lack of ICS, use of LABA or LTRA.

Results

91 adults with asthma, mean age 35.04 ±1.19 years, 47(51.65%) females were evaluated. 27 (29.67%) subjects had a positive screening score on Nijmegen questionnaire and 16(17.58%) were confirmed by progressive exercise testing as having DB. Independent risk factors for DB were psychopathology (p = 0.000002), frequent exacerbator asthma phenotype (p = 0.01) and uncontrolled asthma (p < 0.000001).

Conclusion

Dysfunctional breathing is not infrequent in asthma patients and should be evaluated in asthma patients presenting with psychopathology, frequent severe asthma exacerbations or uncontrolled asthma. Asthma medication (ICS, LABA or LTRA) had no significant relation with dysfunctional breathing.

Respiratory physiotherapy: towards a clearer definition of terminology

Interventions used in clinical practice and research need to be described in sufficient detail to permit accurate replication. Since words and phrases can change their meaning over time, it is important that authors choose their words carefully and define anything which might be ambiguous. 'Breathing exercises' is a phrase which covers a multitude of therapeutic approaches. Recent randomised controlled trials have established the value of teaching patients with asthma to retrain their breathing. However, the descriptions of the breathing interventions are generally inadequate. This problem stems partly from a degree of confusion surrounding terms such as 'diaphragmatic breathing' which has been variously interpreted. A more structured approach to reporting such interventions is proposed. This approach will help to avoid confusion, and will permit the transfer of those interventions found to be effective in research trials into routine clinical practice.

The role of breathing training in asthma management

PURPOSE OF REVIEW

There is considerable public interest in the use of breathing modification techniques in the treatment of asthma. Surveys suggest many people with asthma use them, often without the knowledge of their medical attendants. Extravagant claims have been made about the effectiveness of some techniques, resulting in scepticism from orthodox clinicians. The evidence supporting breathing training for asthma was previously weak, and limited by the small size and methodological limitations of published research.

RECENT FINDINGS

The evidence base for the effectiveness of breathing training has recently improved, with reports from several larger and more methodologically robust controlled trials. These trials are reviewed in this study, and the findings placed in context. Trials have investigated a variety of breathing training programmes delivered by different therapists in different ways. All incorporate some instruction in breathing pattern, usually focusing on slow, regular, nasal, abdominal breathing and reduced ventilation, with patients instructed to practise exercises at home and when symptomatic.

SUMMARY

Current evidence suggests that breathing training programmes can be effective in improving patient-reported outcomes such as symptoms, quality of life and psychological impact; and may reduce the use of rescue bronchodilator medication. There is little evidence that airways physiology, hyper-responsiveness or inflammation is affected by such training. The optimal way of providing breathing training within the context of routine asthma care is still uncertain.

The utility of cardiopulmonary exercise testing in difficult asthma

BACKGROUND

Unexplained persistent breathlessness in patients with difficult asthma despite multiple treatments is a common clinical problem. Cardiopulmonary exercise testing (CPX) may help identify the mechanism causing these symptoms, allowing appropriate management.

METHODS

This was a retrospective analysis of patients attending a specialist-provided service for difficult asthma who proceeded to CPX as part of our evaluation protocol. Patient demographics, lung function, and use of health care and rescue medication were compared with those in patients with refractory asthma. Medication use 6 months following CPX was compared with treatment during CPX.

RESULTS

Of 302 sequential referrals, 39 patients underwent CPX. A single explanatory feature was identified in 30 patients and two features in nine patients: hyperventilation (n = 14), exercise-induced bronchoconstriction (n = 8), submaximal test (n = 8), normal test (n = 8), ventilatory limitation (n = 7), deconditioning (n = 2), cardiac ischemia (n = 1). Compared with patients with refractory asthma, patients without "pulmonary limitation" on CPX were prescribed similar doses of inhaled corticosteroid (ICS) (median, 1,300 μg [interquartile range (IQR), 800-2,000 μg] vs 1,800 μg [IQR, 1,000-2,000 μg]) and rescue oral steroid courses in the previous year (median, 5 [1-6] vs 5 [1-6]). In this group 6 months post-CPX, ICS doses were reduced (median, 1,300 μg [IQR, 800-2,000 μg] to 800 μg [IQR, 400-1,000 μg]; P < .001) and additional medication treatment was withdrawn (n = 7). Patients with pulmonary limitation had unchanged ICS doses post CPX and additional therapies were introduced.

CONCLUSIONS

In difficult asthma, CPX can confirm that persistent exertional breathlessness is due to asthma but can also identify other contributing factors. Patients with nonpulmonary limitation are prescribed inappropriately high doses of steroid therapy, and CPX can identify the primary mechanism of breathlessness, facilitating steroid reduction.

Relationships between measures of dysfunctional breathing in a population with concerns about their breathing

BACKGROUND

Dysfunctional breathing (DB) is implicated in physical and psychological health, however evaluation is hampered by lack of rigorous definition and clearly defined measures. Screening tools for DB include biochemical measures such as end-tidal CO(2), biomechanical measures such assessments of breathing pattern, breathing symptom questionnaires and tests of breathing function such as breath holding time.

AIM

This study investigates whether screening tools for dysfunctional breathing measure distinct or associated aspects of breathing functionality.

METHOD

84 self-referred or practitioner-referred individuals with concerns about their breathing were assessed using screening tools proposed to identify DB. Correlations between these measures were determined.

RESULTS

Significant correlations where found within categories of measures however correlations between variables in different categories were generally not significant. No measures were found to correlate with carbon dioxide levels.

CONCLUSION

DB cannot be simply defined. For practical purposes DB is probably best characterised as a multi-dimensional construct with at least 3 dimensions, biochemical, biomechanical and breathing related symptoms. Comprehensive evaluation of breathing dysfunction should include measures of breathing symptoms, breathing pattern, resting CO(2) and also include functional measures such a breath holding time and response of breathing to physical and psychological challenges including stress testing with CO(2) monitoring.