High prevalence of exercise-induced laryngeal obstruction in athletes

Effects of Exercise-Induced Laryngeal Obstruction in Adolescents: A Qualitative Study

PURPOSE

The purpose of this study was to examine the influence of exercise-induced laryngeal obstruction (EILO) on adolescents.

METHOD

Twenty patients (< 17 years) diagnosed with EILO participated in this study. Patients completed semistructured interviews examining their experience with the health care system, treatment, and the effects of EILO symptoms on quality of life. Interviews were analyzed using a combination of directed and conventional content analyses. Researchers identified seven overarching themes either prior to or during analysis, and 24 subthemes were inductively identified from patient interviews using open, axial, and selective coding.

RESULTS

On average, patients went 1.9 years between symptom onset and EILO diagnosis. Patients described symptom onset as frightening and confusing. Even after initially reporting symptoms to a medical provider, patients went an average of 10.5 months before diagnosis. Patients perceived that delays in diagnosis prevented efficient management and allowed symptoms to escalate. Patients reported that EILO detrimentally influenced athletic performance, forcing them to pace themselves or cease participation altogether. Social and academic effects of EILO included missed classes, difficulty in physical education courses, and resentment from teammates if athletic performance declined. Both athletes and nonathletes indicated that EILO elicited feelings of fear, frustration, dread, guilt, and embarrassment. Patients reported that therapy with a speech-language pathologist (SLP) effectively addressed symptoms; however, employing rescue breathing techniques was often more difficult than anticipated.

CONCLUSIONS

Physical and emotional sequelae associated with EILO may have widespread influence on patient quality of life. Therapy with an SLP reportedly ameliorated EILO symptoms; however, patients indicated that delayed diagnosis allowed negative effects to intensify prior to treatment.

Diagnostic utility of spirometry for children with induced laryngeal obstruction or chronic non-specific cough

PURPOSE

To determine the diagnostic utility of spirometry in distinguishing children with Induced Laryngeal Obstruction (ILO) or chronic non-specific cough (a.k.a. tic cough) from those with mild or moderate to severe asthma.

METHODS

Retrospective cross sectional design. Children diagnosed with ILO (N = 70), chronic non-specific cough (N = 70), mild asthma (N = 60), or moderate to severe asthma (N = 60) were identified from the electronic medical record of a large children's hospital. Spirometry was completed before ILO, non-specific cough, or asthma diagnoses were made by pediatric laryngologists or pulmonologists. Spirometry was performed following American Thoracic Society guidelines and was interpreted by a pediatric pulmonologist. Forced Vital Capacity (FVC), Forced Expiratory Volume in 1 Second (FEV1), FEV1/FVC Ratio (FEV1/FVC), Forced Mid-Expiratory Flow 25--75 % (FEF25-75%), pulmonologist interpretation of flow volume loops, and overall exam findings were extracted from the medical record.

RESULTS

Ninety seven percent of children with ILO or chronic non-specific cough presented with spirometry values within normative range. Patients with ILO, non-specific cough, and mild asthma presented with FVC, FEV1, FEV1/FVC, and FEF25-75% values in statistically similar range. Children with moderate to severe asthma presented with significantly reduced FVC (p < .001), FEV1 (p < .001), FEV1/FVC (p < .001), and FEF25-75% (p < .001) values when compared with patients in the other groups. Flow volume loops were predominantly normal for children with ILO and non-specific cough.

CONCLUSIONS

Findings indicate that ILO and chronic non-specific cough can neither be diagnosed nor differentiated from mild asthma using spirometry alone. Spirometry should therefore be used judiciously with this population, bearing in mind the limitations of the procedure. Future research should determine the most effective and efficient ways of delineating ILO and non-specific cough from other respiratory conditions in children.

Long-Term Outcomes of Respiratory Retraining Therapy for Exercise-Induced Laryngeal Obstruction

OBJECTIVE

To assess the long-term outcomes and efficacy of respiratory retraining therapy in patients with exercise-induced laryngeal obstruction (EILO).

METHODS

A retrospective chart review and prospective questionnaire-based survey were conducted on 88 patients who received respiratory retraining therapy for EILO at our institution over the past 5 years RESULTS: Thirty-four patients were included in the final analysis, with a mean age at symptom onset and age at initial evaluation of 13.67 ± 2.96 and 15.12 ± 3.48, respectively. We found a statistically significant difference in the pretreatment and post-treatment Dyspnea indices following respiratory retraining therapy, with a mean difference of 12.03 ± 7.18 (P < 0.001). When asked about the effectiveness of respiratory retraining therapy, the majority of patients (n = 28) reported improvement (13.3% "a little," 13.3% "somewhat better," 53.3% ("a lot better," and 13.3% complete resolution of symptoms. Only two patients (6.7%) responded that their breathing "did not get better." The most effective therapy techniques cited by patients were abdominal breathing (n = 10), ratio breathing (n = 5), and pursed lips or "straw" breathing (n = 5).

CONCLUSIONS

Respiratory retraining therapy represents an effective technique in both the short-term and long-term management of EILO. This therapy remains the first line in the management of EILO due to its ease of administration, non-invasive nature, and durable effect on breathing function.

A speech therapy treatment protocol for exercise induced laryngeal obstruction

Background

Exercise induced laryngeal obstruction (EILO) is a common cause of exertional breathing problems in young individuals, relevant to 5%-7% of young people. It is caused by paradoxical inspiratory adduction of laryngeal structures and diagnosed by continuous visualization of the larynx during high intensity exercise. Empirical data suggest that EILO consists of different subtypes that require different therapeutic approaches. Currently applied treatment approaches do not rest on randomized controlled trials (RCTs), and thus evidence-based guidelines cannot be established. This protocol describes the speech therapy treatment approach which is applied to EILO patients in a large prospective RCT called HelpILO.

Methods and analysis

Consenting patients consecutively diagnosed with EILO at Haukeland University Hospital are randomized into four treatment arms. Speech therapy is represented in two of these, provided in a structured manner based on general speech therapy principles and abdominal breathing, combined with experience obtained with these patients at our hospital during the last decades. The main outcome measure of HelpILO is changes of laryngoscopically visualized laryngeal adduction, rated at peak exercise before vs. after interventions, using a validated scoring system.

Ethics and dissemination

Despite widespread use of speech therapy in patients with EILO, this approach is insufficiently tested in RCTs, and the study is therefore considered ethically appropriate. The study will provide knowledge listed as a priority in a recent statement issued by major respiratory and laryngological societies and requested by clinicians and researchers engaged in this area. The results will be presented at relevant conferences, patient fora, and media platforms, and published in relevant peer reviewed international journals.

Feasibility of Constant Work Rate Testing to Detect Exercise-Induced Laryngeal Obstruction

INTRODUCTION

Exercise-induced laryngeal obstruction (EILO) is a condition in which laryngeal structures inappropriately obstruct the upper airway during exercise. The standard diagnostic test for EILO is the continuous laryngoscopy during exercise (CLE) test, usually performed with an incremental work rate protocol regardless of the nature of the triggering event. Typically, laryngeal obstruction occurs only briefly at the end of an incremental test, near peak work capacity. We aimed to investigate constant work rate (CWR) protocols for CLE testing to expand diagnostic test modalities and improve the understanding of EILO.

METHODS

In this prospective, self-controlled feasibility study, 10 patients with EILO performed both an incremental and a CWR CLE test at 70%, 80%, and 90% of maximal exercise capacity. Laryngoscopic video data were recorded and compared, and we evaluated the ability of CWR to reproduce the symptoms and laryngeal obstruction seen in incremental testing.

RESULTS

In 70%-90% of cases, CWR testing induced at least the same severity of obstruction as incremental testing and CLE scores remained comparable across test modalities. CWR at 70% allowed observation of laryngeal obstruction for a significantly longer duration than in incremental testing (158 s; 95% confidence interval, 25-291 s; P = 0.027). Dyspnea intensity appeared higher during CWR testing compared with incremental testing.

CONCLUSIONS

Submaximal CWR CLE testing is feasible and able to induce EILO equivalent to the standard incremental CLE test. This is the first step toward tailored CLE exercise protocols, and further studies are now needed to establish the utility of CWR in clinical and research settings.

Prevalence and characterisation of exercise-induced laryngeal obstruction in patients with exercise-induced dyspnoea

OBJECTIVE

The prevalence of exercise-induced laryngeal obstruction is largely unknown. This study aimed to evaluate the prevalence of this condition in a selected study population of patients with exercise-induced dyspnoea.

METHOD

A retrospective analysis was conducted of demographic data, co-morbidities, medication, symptoms, performance level of sporting activities, continuous laryngoscopy exercise test results and subsequent treatment.

RESULTS

Data from 184 patients were analysed. The overall prevalence of exercise-induced laryngeal obstruction in the study population was 40 per cent, and the highest prevalence was among females aged under 18 years (61 per cent). However, a high prevalence among males aged under 18 years (50 per cent) and among adults regardless of gender (34 per cent) was also found.

CONCLUSION

The prevalence of exercise-induced laryngeal obstruction is clinically relevant regardless of age and gender. Clinicians are encouraged to consider exercise-induced laryngeal obstruction as a possible diagnosis in patients suffering from exercise-induced respiratory symptoms. No single characteristic that can distinguish exercise-induced laryngeal obstruction from other similar conditions was identified.

A multidimensional strategy to managing dysfunctional breathing and exercise-induced laryngeal obstruction in adolescent athletes

BACKGROUND

Exercise induced laryngeal obstruction (EILO) causes inspiratory distress in the upper airway in many adolescent athletes. The nature of EILO is not fully understood, and effective management strategies are lacking. This study aimed to assess the effectiveness of a multidimensional individually tailored intervention, including Norwegian Psychomotor Physiotherapy (NPMP), elements of cognitive behavioural therapy and a rehabilitation plan, in reducing inspiratory distress and dysfunctional breathing in adolescent athletes with EILO.

METHODS

A mixed methods design, which combined qualitative and quantitative research, was used. Data, including subjective experiences of respiratory distress, findings from body examinations and objective measurements of lung function and aerobic capacity were gathered before and after a five month intervention involving 18 participants.

RESULTS

Following the intervention, the participants showed a reduction in respiratory distress and anxiousness associated with their breathing difficulties. Furthermore, the participants reported to be more in control of their breathing. The body assessments revealed a more functional breathing motion and improved posture, which imply that the breathing was less thoracic and more diaphragmatic in rest and exercise in all participants after the intervention.

CONCLUSIONS

Our results suggest that a multidimensional individually tailored intervention, including NPMP based physiotherapy, cognitive behavioural therapy elements, and a rehabilitation plan may reduce inspiratory distress and dysfunctional breathing in athletes with EILO.

TRIAL REGISTRATION

ClinicalTrials.gov Protocol Registration and Results system NCT06033755, date of registration: September12, 2023. Retrospectively registered.

Examining therapy duration in adults with induced laryngeal obstruction (ILO)

OBJECTIVE

This study examined the number of therapy sessions required to sufficiently improve (exercise) induced laryngeal obstruction (EILO/ILO) symptoms for discharge. Factors predicting therapy duration were examined as was the likelihood of patients returning for additional therapy sessions following initial discharge.

METHODS

Retrospective observational cohort design. Data for 350 patients were gathered from the University of Wisconsin-Madison Voice and Swallow Clinics Outcome Database. Patients (>18 years of age) diagnosed with EILO/ILO received therapy from a Speech-Language Pathologist (SLP) and were successfully discharged. EILO/ILO treatment details, symptoms, triggers, medical comorbidities, and patient demographics were collected from initial evaluations and subsequent course of therapy.

RESULTS

Patients required an average of 3.59 (SD = 3.7) therapy sessions prior to discharge. A comorbid behavioral health diagnosis (p = .026), higher Vocal Handicap Index Score (p = .009) and reduced physical activity due to EILO/ILO symptoms (p = .032) were associated with increased therapy duration. Patients with ILO or EILO with secondary environmental triggers required significantly more sessions than those with exercise-induced symptoms (p < .01). Eight percent of patients returned for additional sessions following discharge. Patients returning for additional sessions all came from affluent neighborhoods as measured by the Area Deprivation Index (ADI).

CONCLUSIONS

Patients with EILO/ILO required an average of 3.59 therapy sessions prior to discharge. As such, 4 sessions is a reasonable estimate for clinicians to provide patients. Six sessions may be a more conservative estimate for patients who present with a behavioral health diagnosis, a voice complaint, or reduced physical activity from EILO/ILO symptoms.

Airflow through the supraglottis during inspiration

Exercise-induced laryngeal obstruction is a paradoxical laryngeal closure during inspiration at high-intensity exercise, with supraglottic closure being most common. This study develops a model based on the computational fluid dynamics to investigate airflow velocity and pressure and the air-induced loads on the supraglottis at various inspiratory flow rates. It is found that at high flow rates, positive wall pressure is formed in the hypopharynx localise towards its lower region, while posterior supraglottic wall pressures shift from positive to negative. These findings suggest that high inspiratory flow rates may increase supraglottic pressure differentials, ultimately contributing in the collapse.

Exercise-Induced Dyspnea in Collegiate Athletes: Are We Missing the Diagnosis?

OBJECTIVES

Exercise-induced dyspnea (EID) can disrupt an athlete's participation and performance in their given sport. Differential diagnosis of EID is often completed using subjective report and may be inaccurate, therefore increasing the frustration and stress of the athlete. This nonexperimental research study was used to determine prevalence of EID and related respiratory symptoms in athletes at a small, Division I university.

METHODS

An anonymous survey was provided to athletes at Murray State University as they registered for participation in sports for the 2020-2021 school year. Data from this survey was analyzed as to reported physician-given diagnosis of a respiratory disorder as well as reported symptoms of EID.

RESULTS

Results showed that athletes with a physician-given diagnosis often did not report symptoms or responses to medications that support that diagnosis. Additionally, athletes frequently reported symptoms of EID without a formal diagnosis of a respiratory disorder.

CONCLUSIONS

These findings provide preliminary insight and pilot data that may be used to understand the prevalence of EID in collegiate athletes and the need for improved methods of diagnosis for etiologies of EID.

A longitudinal follow-up of continuous laryngoscopy during exercise test scores in athletes irrespective of laryngeal obstruction, respiratory symptoms, and intervention

BACKGROUND

Exercise-induced laryngeal obstruction (EILO) is diagnosed by the continuous laryngoscopy during exercise (CLE) test. Whether or how much CLE test scores vary over time is unknown. This study aimed to compare CLE test scores in athletes over time, irrespective of respiratory symptoms and grade of laryngeal obstruction.

METHODS

Ninety-eight athletes previously screened for EILO were invited for a follow-up CLE test irrespective of CLE scores and respiratory symptoms. Twenty-nine athletes aged 16-27 did a follow-up CLE test 3-23 months after the baseline test. Laryngeal obstruction at the glottic and supraglottic levels was graded by the observer during exercise, at baseline and follow-up, using a visual grade score (0-3 points).

RESULTS

At baseline, 11 (38%) of the 29 athletes had moderate laryngeal obstruction and received advice on breathing technique; among them, 8 (73%) reported exercise-induced dyspnea during the last 12 months. At follow-up, 8 (73%) of the athletes receiving advice on breathing technique had an unchanged supraglottic score. Three (17%) of the 18 athletes with no or mild laryngeal obstruction at baseline had moderate supraglottic obstruction at follow-up, and none of the 3 reported exercise-induced dyspnea.

CONCLUSIONS

In athletes with repeated testing, CLE scores remain mostly stable over 3-24 months even with advice on breathing technique to those with EILO. However, there is some intraindividual variability in CLE scores over time.

TRIAL REGISTRATION

ISRCTN, ISRCTN60543467, 2020/08/23, retrospectively registered, ISRCTN - ISRCTN60543467: Investigating conditions causing breathlessness in athletes.

Therapy Outcomes for Teenage Athletes With Exercise-Induced Laryngeal Obstruction

PURPOSE

This study examined treatment outcomes of speech-language pathology intervention addressing exercise-induced laryngeal obstruction (EILO) symptoms in teenage athletes.

METHOD

A prospective cohort design was utilized; teenagers diagnosed with EILO completed questionnaires during initial EILO evaluations, posttherapy, 3-month posttherapy, and 6-month posttherapy. Questionnaires examined the frequency of breathing problems, the use of the techniques taught in therapy, and the use of inhaler. Patients completed the Pediatric Quality of Life (PedsQL) inventory at all time points.

RESULTS

Fifty-nine patients completed baseline questionnaires. Of these, 38 were surveyed posttherapy, 32 at 3-month posttherapy, and 27 at 6-month posttherapy. Patients reported more frequent and complete activity participation immediately posttherapy (p = .017) as well as reduced inhaler use (p = .036). Patients also reported a significant reduction in the frequency of breathing problems 6-month posttherapy (p = .015). Baseline PedsQL physical and psychosocial scores were below normative range and were not impacted by therapy. Baseline physical PedsQL score significantly predicted frequency of breathing difficulty 6-month posttherapy (p = .04), as better baseline scores were associated with fewer residual symptoms.

CONCLUSIONS

Therapy with a speech-language pathologist for EILO allowed for more frequent physical activity following therapy completion and decreased dyspnea symptoms 6-month posttherapy. Therapy was associated with a decrease in inhaler use. PedsQL scores indicated mildly poor health-related quality of life even after EILO symptoms improved. Findings support therapy as an effective treatment for EILO in teenage athletes and suggest that dyspnea symptoms may continue to improve following discharge as patients continue using therapy techniques.

Prevalence and impact of exercise-induced laryngeal obstruction in asthma: a study protocol for a cross-sectional and longitudinal study

INTRODUCTION

Exercise-induced laryngeal obstruction (EILO) and exercise-induced asthma can cause troublesome respiratory symptoms that can be difficult to distinguish between. Further, there is now a growing appreciation that the two conditions may coexist, complicating the interpretation of symptoms. The primary aim of this study is to investigate the prevalence of EILO in patients with asthma. Secondary aims include evaluation of EILO treatment effects and investigation of comorbid conditions other than EILO in patients with asthma.

METHODS AND ANALYSIS

The study will be conducted at Haukeland University Hospital and Voss Hospital in Western Norway, and enrol 80-120 patients with asthma and a control group of 40 patients without asthma. Recruitment started in November 2020, and data sampling will continue until March 2024. Laryngeal function will be assessed at baseline and at a 1-year follow-up, using continuous laryngoscopy during high-intensity exercise (CLE). Immediately after the EILO diagnosis is verified, patients will be treated with standardised breathing advice guided by visual biofeedback from the laryngoscope video screen. The primary outcome will be the prevalence of EILO in patients with asthma and control participants. Secondary outcomes include changes in CLE scores, asthma-related quality of life, asthma control and number of the asthma exacerbations, as assessed between baseline and the 1-year follow-up.

ETHICS AND DISSEMINATION

Ethical approval has been obtained from the Regional Committee for Medical and Health Research Ethics, Western Norway, (ID number 97615). All participants will provide signed informed consent before enrolment. The results will be presented in international journals and conferences.

TRIAL REGISTRATION NUMBER

NCT04593394.

Exercise induced laryngeal obstruction (EILO) in children and young people: Approaches to assessment and management

Exercise Induced Laryngeal Obstruction (EILO) is characterised by breathlessness, cough and/or noisy breathing particularly during high intensity exercise. EILO is a subcategory of inducible laryngeal obstruction where exercise is the trigger that provokes inappropriate transient glottic or supraglottic narrowing. It is a common condition affecting 5.7-7.5% of the general population and is a key differential diagnosis for young athletes presenting with exercise related dyspnoea where prevalence rates go as high as 34%. Although the condition has been recognised for a long time, little attention, and awareness of the condition results in many young people dropping out of sporting participation due to troublesome symptoms. With evolving understanding of the condition, diagnostic tests and interventions, this review looks to present the current available evidence and best practice when managing young people with EILO.

Diagnostic work-up of exercise-induced laryngeal obstruction

PURPOSE

Exercise-induced laryngeal obstruction (EILO) is suspected when dyspnea associated with upper airway symptoms is triggered by exercise. This condition affects mainly adolescent athletes. Visualization of the obstruction, while the patient is experiencing the symptoms during continuous laryngoscopy during exercise (CLE-test) is the gold standard for diagnosing EILO. Our study aims to evaluate the prevalence of EILO in a population presenting exercise-induced inspiratory symptoms (EIIS) or uncontrolled asthma with exertional symptoms. The second objective was to evaluate the diagnostic strength of laryngology consultation (LC) and pulmonary function tests (PFTs).

METHODS

All patients referred to our center for EIIS or uncontrolled asthma with exertional symptoms were included. EILO diagnosis was made if Maat score was > 2 for patients with CLE-test or if there were inspiratory anomalies on PFTs and LC. The sensitivity and specificity of LC and PFTs as diagnostic tools were calculated considering CLE-test as the gold standard.

RESULTS

Sixty two patients were referred to our center for EIIS or uncontrolled asthma with exertional symptoms. EILO was diagnosed in 28 patients (56%) with associated asthma in 9 patients (18%). The sensibility and specificity of LC for supraglottic anomalies were 75% and 60%, respectively. The sensibility and specificity of PFTs were 61% and 89%, respectively.

CONCLUSIONS

There was a high prevalence of EILO among patients with EIIS and uncontrolled asthma. Some clinical characteristics might guide the diagnosis. Nevertheless, CLE-test remained the gold standard for EILO diagnosis and identification of the dysfunctional upper airway site to provide specific management.

Use of inhaled ipratropium bromide to improve exercise-induced laryngeal obstruction cannot be recommended

Introduction

Exercise-induced laryngeal obstruction (EILO) is a common cause of exertional breathing problems in young adults. Current management generally consists of breathing advice, speech therapy, inspiratory muscle training or supraglottoplasty in highly motivated subjects with supraglottic collapse. Inhaled ipratropium bromide (IB) is a muscarinic receptor antagonist used to treat asthma that is suggested in a few reports to improve EILO symptoms. The aim of the present study was to investigate effects of inhaled IB in EILO diagnosed by continuous laryngoscopy exercise (CLE) test and classified by CLE scores.

Methods

A randomised crossover trial was conducted at Haukeland University Hospital, Bergen, Norway, enrolling participants diagnosed with EILO defined by characteristic symptoms and CLE score ≥3 (range 0-12). Two consecutive CLE tests were performed within 2 weeks, one test with and one test without prior administration of inhaled IB in a randomised order. Main outcomes were the CLE score, dyspnoea measured using a modified BORG scale (range 0-10) and cardiopulmonary exercise data provided by the CLE test.

Results

20 participants (14 females) aged 12-25 years participated, and all ran to exhaustion on both tests. Mean CLE score, BORG score and peak oxygen consumption were similar in tests performed with and without IB; mean differences (95% confidence interval) were 0.08 (-0.28-0.43), 0.35 (-0.29-0.99) and -0.4 (-1.9-1.1) mL·kg^-1·min^-1, respectively.

Conclusion

Inhaled IB did not improve CLE score, dyspnoea or exercise capacity in subjects with EILO. The study does not support the use of inhaled IB to treat EILO.

Inducible Laryngeal Obstruction Differential Diagnosis in Adolescents and Adults: A Tutorial

Inducible laryngeal obstruction (ILO), formerly referred to as paradoxical vocal fold motion and vocal cord dysfunction, is a complex disorder of the upper airway that requires skillful differential diagnosis. There are several medical conditions that may mimic ILO (or which ILO may mimic) that should be considered in the differential diagnosis before evidence-supported behavioral intervention is initiated to mitigate or eliminate this upper airway condition. A key in treatment planning is determination of an isolated presentation of ILO or ILO concurrent with other conditions that affect the upper airway. Accurate, timely differential diagnosis in the clinical assessment of this condition mitigates delay of targeted symptom relief and/or insufficient intervention. Accurate assessment and nuanced clinical counseling are necessary to untangle concurrent, competing conditions in a single patient. This tutorial describes the common and rare mimics that may be encountered by medical professionals who evaluate and treat ILO, with particular attention to the role of the speech-language pathologist. Speech-language pathologists receive referrals for ILO from several different medical specialists (allergy, pulmonology, and sports medicine), sometimes without a comprehensive team assessment. It is paramount that speech-language pathologists who assess and treat this disorder have a solid understanding of the conditions that may mimic ILO. Summary tables that delineate differential diagnosis considerations for airway noise, origin of noise, symptoms, triggers, role of the speech-language pathologist, and β-agonist response are included for clinician reference. A clinical checklist is also provided to aid clinicians in the critical assessment process.

The continuous laryngoscopy exercise test in severe or in difficult-to-treat asthma in adults: a systematic review

OBJECTIVE

A systematic review was performed to determine if the continuous laryngoscopy exercise test (CLE) has been used in the diagnostics of exercise dyspnea in adults with asthma, and whether inducible laryngeal obstruction (ILO) is found in those with asthma or with severe or difficult-to-treat asthma.

DATA SOURCES

We used Scopus and PubMed databases. The articles published up to 13 August 2019 were considered.

STUDY SELECTIONS

We excluded manuscripts that did not contain information about adult patients with asthma. We included six studies from 59 search results in Scopus and none from the 17 search results in PubMed.

RESULTS

The articles included 455 study individuals. Of these, 229 (50.3%) had diagnosed asthma or were treated with asthma medication. Altogether 31/229 (13.5%) subjects with diagnosis of asthma or previous asthma treatment had exercise-induced laryngeal obstruction (EILO) as comorbidity. The CLE test was performed on 229 patients with asthma. The method was used only for differential diagnosis of exercise-induced dyspnea to confirm EILO. At least 10/455 (2.2%) out of the 455 subjects experienced adverse events.

CONCLUSIONS

This systematic review revealed that only a small proportion of patients with asthma had undergone the CLE test to assess exercise-induced dyspnea. None of the selected manuscripts reported severity of asthma. Whether CLE provides a valuable diagnostic tool for patients with severe or difficult-to-treat asthma cannot be determined according to this review.

Vocal cord dysfunction/inducible laryngeal obstruction: novel diagnostics and therapeutics

INTRODUCTION

Vocal cord dysfunction/inducible laryngeal obstruction (VCD/ILO) is an important medical condition but understanding of the condition is imperfect. It occurs in healthy people but often co-exists with asthma. Models of VCD/ILO pathophysiology highlight predisposing factors rather than specific mechanisms and disease expression varies between people, which is seldom appreciated. Diagnosis is often delayed, and the treatment is not evidence based.

AREAS COVERED

A unified pathophysiological model and disease phenotypes have been proposed. Diagnosis is conventionally made by laryngoscopy during inspiration with vocal cord narrowing >50% Recently, dynamic CT larynx was shown to have high specificity (>80%) with potential as a noninvasive, swift, and quantifiable diagnostic modality. Treatment entails laryngeal retraining with speech pathology intervention and experimental therapies such as botulinum toxin injection. Multidisciplinary team (MDT) clinics are a novel innovation with demonstrated benefits including accurate diagnosis, selection of appropriate treatment, and reductions in oral corticosteroid exposure.

EXPERT OPINION

Delayed diagnosis of VCD/ILO is pervasive, often leading to detrimental treatments. Phenotypes require validation and CT larynx can reduce the necessity for laryngoscopy, thereby fast-tracking diagnosis. MDT clinics can optimize management. Randomized controlled trials are essential to validate speech pathology intervention and other treatment modalities and to establish international standards of care.

Diagnosis and management of allergy and respiratory disorders in sport: An EAACI task force position paper

Allergy and respiratory disorders are common in young athletic individuals. In the context of elite sport, it is essential to secure an accurate diagnosis in order to optimize health and performance. It is also important, however, to consider the potential impact or consequences of these disorders, in recreationally active individuals engaging in structured exercise and/or physical activity to maintain health and well-being across the lifespan. This EAACI Task Force was therefore established, to develop an up-to-date, research-informed position paper, detailing the optimal approach to the diagnosis and management of common exercise-related allergic and respiratory conditions. The recommendations are informed by a multidisciplinary panel of experts including allergists, pulmonologists, physiologists and sports physicians. The report is structured as a concise, practically focussed document, incorporating diagnostic and treatment algorithms, to provide a source of reference to aid clinical decision-making. Throughout, we signpost relevant learning resources to consolidate knowledge and understanding and conclude by highlighting future research priorities and unmet needs.

International Olympic Committee (IOC) consensus statement on acute respiratory illness in athletes part 2: non-infective acute respiratory illness

Acute respiratory illness (ARill) is common and threatens the health of athletes. ARill in athletes forms a significant component of the work of Sport and Exercise Medicine (SEM) clinicians. The aim of this consensus is to provide the SEM clinician with an overview and practical clinical approach to non-infective ARill in athletes. The International Olympic Committee (IOC) Medical and Scientific Committee appointed an international consensus group to review ARill in athletes. Key areas of ARill in athletes were originally identified and six subgroups of the IOC Consensus group established to review the following aspects: (1) epidemiology/risk factors for ARill, (2) infective ARill, (3) non-infective ARill, (4) acute asthma/exercise-induced bronchoconstriction and related conditions, (5) effects of ARill on exercise/sports performance, medical complications/return-to-sport (RTS) and (6) acute nasal/laryngeal obstruction presenting as ARill. Following several reviews conducted by subgroups, the sections of the consensus documents were allocated to 'core' members for drafting and internal review. An advanced draft of the consensus document was discussed during a meeting of the main consensus core group, and final edits were completed prior to submission of the manuscript. This document (part 2) of this consensus focuses on respiratory conditions causing non-infective ARill in athletes. These include non-inflammatory obstructive nasal, laryngeal, tracheal or bronchial conditions or non-infective inflammatory conditions of the respiratory epithelium that affect the upper and/or lower airways, frequently as a continuum. The following aspects of more common as well as lesser-known non-infective ARill in athletes are reviewed: epidemiology, risk factors, pathology/pathophysiology, clinical presentation and diagnosis, management, prevention, medical considerations and risks of illness during exercise, effects of illness on exercise/sports performance and RTS guidelines.

Exercise-induced laryngeal obstruction (EILO) in athletes: a narrative review by a subgroup of the IOC Consensus on 'acute respiratory illness in the athlete'

Exercise-induced laryngeal obstruction (EILO) is caused by paradoxical inspiratory adduction of laryngeal structures during exercise. EILO is an important cause of upper airway dysfunction in young individuals and athletes, can impair exercise performance and mimic lower airway dysfunction, such as asthma and/or exercise-induced bronchoconstriction. Over the past two decades, there has been considerable progress in the recognition and assessment of EILO in sports medicine. EILO is a highly prevalent cause of unexplained dyspnoea and wheeze in athletes. The preferred diagnostic approach is continuous visualisation of the larynx (via laryngoscopy) during high-intensity exercise. Recent data suggest that EILO consists of different subtypes, possibly caused via different mechanisms. Several therapeutic interventions for EILO are now in widespread use, but to date, no randomised clinical trials have been performed to assess their efficacy or inform robust management strategies. The aim of this review is to provide a state-of-the-art overview of EILO and guidance for clinicians evaluating and treating suspected cases of EILO in athletes. Specifically, this review examines the pathophysiology of EILO, outlines a diagnostic approach and presents current therapeutic algorithms. The key unmet needs and future priorities for research in this area are also covered.

Conundrums in the breathless athlete; exercise induced laryngeal obstruction or asthma?

PURPOSE

Exercise-induced bronchoconstriction (EIB) and exercise-induced laryngeal obstruction (EILO) are two disorders commonly considered when athletes complain of exertional dyspnea. They are highly different but often confused. We aimed to address this diagnostic challenge and its consequences in elite athletes.

METHODS

We included all athletes competing at national or international level, referred to our institution for workup for EILO during 2013-2016. We diagnosed EILO from video-recorded laryngoscopy performed during maximal cardiopulmonary treadmill exercise (CLE-test). Symptoms and previous diagnostic evaluations were obtained from referral letters and chart reviews.

RESULTS

EILO was diagnosed in 73/101 referred athletes, of whom 70/73 had moderate/severe supraglottic obstruction and 3/73 had primarily glottic obstruction with only minor supraglottic involvement. Of the 73 athletes with EILO, we were able to identify objective tests for asthma in 55 participants, of whom 22 had findings supporting asthma. However, 58/73 had used asthma therapy at some time previously, with current use in 28. Only three reported that asthma medication had improved their exercise related breathing problems, two of whom with tests confirming asthma. Treatment for EILO improved breathing problems in all but four.

CONCLUSIONS

Objective testing verified EILO in most of the referred athletes. EILO coexisting with asthma was common, and large proportions had used asthma medication; however, few reported effect on exercise related breathing problems. Unexplained persistent exertional dyspnoea must not lead to indiscriminate escalation of asthma treatment, but instead incite investigation for EILO, either as a co-morbidity or as a differential diagnosis.

Evaluating Children and Adolescents with Suspected Exercise Induced Asthma: Real Life Data

OBJECTIVE

Exercise-induced bronchoconstriction (EIB) occurs frequently in children and adolescents and may be a sign of insufficient asthma control. EIB is often evaluated by respiratory symptoms, spirometry, eNO measurement and methacholine testing (MCT) instead of time consuming exercise test. Aim of this study was to analyse the amount of patients for which an exercise challenge in a cold chamber (ECC) was needed for a clear EIB diagnosis, to characterize EIB phenotypes and the incidence of exercise induced laryngeal obstruction (EILO) in a large cohort of patients with EIB.

METHODS

A retrospective analysis was performed in 595 children and adolescents (mean age 12.1 years) with suspected EIB from January 2014 to December 2018. Complete data sets of skin prick test, spirometry, eNO and MCT were available from 336 patients.

RESULTS

An ECC to confirm the EIB diagnosis was performed in 125 (37.2%) of patients. Three EIB phenotypes were detected: group 1: EIB without allergic sensitization (n=159); group 2: EIB with other than house dust mite (HDM) sensitization (n=87) and group 3: EIB with HDM sensitization (n=90). MCT and eNO showed significant differences between the subgroups: An eNO>46 ppb and/or a MCT<0.1 mg was found in 23.9% vs. 50.6% vs. 57.8% in group 1-3, respectively. Significantly more patients suffered from EILO in group 1 compared to group 2 and 3 (n=13 vs. n=1).

CONCLUSION

EIB without sensitization is as often as EIB with sensitization. In patients without sensitization, EILO has to be considered as a possible cause of symptoms during exercise.

Stressed and Distressed: Potential Underpinnings of Exercise-Related Inspiratory Distress in Adolescent Sport Performers

Many adolescent sport performers present with exercise-related respiratory symptoms consistent with exercise-induced laryngeal obstruction (EILO). The pathogenic underpinnings of EILO are not fully resolved, and existing behavioral management includes therapies targeting laryngeal physiology whereas surgical interventions target laryngeal anatomical anomalies. Recent findings from research and clinical practice indicate that psychological stress and thoracic breathing co-occur with laryngeal tightness in adolescent sport performers with EILO. This Perspective article theorizes on this potential coexistence. It discusses possible underpinnings of respiratory symptoms (including EILO) and thoracic breathing in adolescent sport performers by considering the effects of various stressors to which adolescent sport performers are exposed, and the impact these may have on the breathing, including in terms of laryngeal narrowing. The effect of stress on the breathing is examined in light of the reciprocal communication between the brain and the body and the relationship between psychological stress and stress responses in the respiratory system mediated by the autonomic nervous system. To inform decision-making and clinical awareness in this area, it may be worth expanding the focus from targeting mainly laryngeal structures to also include constrictions of the airways and the effects of thoracic breathing on the larynx during exercise. The importance of considering respiratory distress from a multidimensional perspective, and of incorporating the complexity of sport performers' psychological and physical experiences in the management of their health and well-being, is emphasized.

IMPACT

This Perspective adds to the understanding of respiratory distress in populations other than adults, which is important and necessary.

LAY SUMMARY

Adolescent sport performers are exposed to a number of stressors that may affect breathing and laryngeal narrowing, which in turn may have implications for the management of their overall health and well-being.

Do not forget asthma comorbidities in pediatric severe asthma!

Asthma is the most common chronic respiratory disease in childhood. The long-term goals in managing asthma aim to control symptoms and prevent exacerbations, as well as to reduce side effects of therapy and mortality disease-related. Most of patients have mild to moderate asthma and respond well to standard therapies. However, a minor proportion of children with asthma has severe disease that remains uncontrolled despite optimal adherence to prescribed therapy and treatment of contributory factors, including trigger exposures and comorbidities, which can mimic or worsen asthma and contribute to exacerbations and poor quality of life. Evaluation of comorbidities is fundamental to optimize the management of the disease in a subgroup of patients with poor responder asthma. The overall aim of this article is to describe characteristics of main pediatric severe asthma comorbidities reported in literature, giving clinicians tools to recognize and manage properly these conditions.

Exercise-induced Laryngeal Obstruction: Protocol for a Randomized Controlled Treatment Trial

BACKGROUND

Exercise-induced laryngeal obstruction (EILO) is a common cause of exertional breathing problems in young individuals, caused by paradoxical inspiratory adduction of laryngeal structures, and diagnosed by continuous visualization of the larynx during high-intensity exercise. Empirical data suggest that EILO consists of different subtypes, possibly requiring different therapeutic approaches. Currently applied treatments do not rest on randomized controlled trials, and international guidelines based on good evidence can therefore not be established. This study aims to provide evidence-based information on treatment schemes commonly applied in patients with EILO.

METHODS AND ANALYSIS

Consenting patients consecutively diagnosed with EILO at Haukeland University Hospital will be randomized into four non-invasive treatment arms, based on promising reports from non-randomized studies: (A) standardized information and breathing advice only (IBA), (B) IBA plus inspiratory muscle training, (C) IBA plus speech therapy, and (D) IBA plus inspiratory muscle training and speech therapy. Differential effects in predefined EILO subtypes will be addressed. Patients failing the non-invasive approach and otherwise qualifying for surgical treatment by current department policy will be considered for randomization into (E) standard or (F) minimally invasive laser supraglottoplasty or (G) no surgery. Power calculations are based on the main outcomes, laryngeal adduction during peak exercise, rated by a validated scoring system before and after the interventions.

ETHICS AND DISSEMINATION

The study will assess approaches to EILO treatments that despite widespread use, are insufficiently tested in structured, verifiable, randomized, controlled studies, and is therefore considered ethically sound. The study will provide knowledge listed as a priority in a recent statement issued by the European Respiratory Society, requested by clinicians and researchers engaged in this area, and relevant to 5-7% of young people. Dissemination will occur in peer-reviewed journals, at relevant media platforms and conferences, and by engaging with patient organizations and the healthcare bureaucracy.

Keeping Pace with Adolescent Asthma: A Practical Approach to Optimizing Care

Known for their pre-occupation with body image, self-identity creation, peer acceptance, and risk-taking behaviors, adolescents with asthma face unique challenges. Asthma is a heterogeneous disease and accurate diagnosis requires assessment through detailed clinical history, examination, and objective tests. Diagnostic challenges exist as many adolescents can present with asthma-like symptoms but do not respond to asthma treatment and risk being mis-diagnosed. Under-recognition of asthma symptoms and denial of disease severity must also be addressed. The over-reliance on short-acting beta-agonists in the absence of anti-inflammatory therapy for asthma is now deemed unsafe. Adolescents with mild asthma benefit from symptom-driven treatment with combination inhaled corticosteroids (ICS) and long-acting beta-agonist (LABA) on an as-required basis. For those with moderate-to-persistent asthma requiring daily controller therapy, maintenance and reliever therapy using the same ICS-LABA controller simplifies treatment regimes, while serving to reduce exacerbation risk. A developmentally staged approach based on factors affecting asthma control in early, middle, and late adolescence enables better understanding of the individual's therapeutic needs. Biological, psychological, and social factors help formulate a risk assessment profile in adolescents with difficult-to-treat and severe asthma. Smoking increases risks of developing asthma symptoms, lung function deterioration, and asthma exacerbations. Morbidity associated with e-cigarettes or vaping calls for robust efforts towards smoking and vaping cessation and abstinence. As adolescents progress from child-centered to adult-oriented care, coordination and planning are required to improve their self-efficacy to ready them for transition. Frequent flare-ups of asthma can delay academic attainment and adversely affect social and physical development. In tandem with healthcare providers, community and schools can link up to help shoulder this burden, optimizing care for adolescents with asthma.

The Road to the Beijing Winter Olympics and Beyond: Opinions and Perspectives on Physiology and Innovation in Winter Sport

Beijing will host the 2022 Winter Olympics, and China strengthens research on various aspects to allow their athletes to compete successfully in winter sport. Simultaneously, Government-directed initiatives aim to increase public participation in recreational winter sport. These parallel developments allow research to advance knowledge and understanding of the physiological determinants of performance and health related to winter sport. Winter sport athletes often conduct a substantial amount of training with high volumes of low-to-moderate exercise intensity and lower volumes of high-intensity work. Moreover, much of the training occur at low ambient temperatures and winter sport athletes have high risk of developing asthma or asthma-related conditions, such as exercise-induced bronchoconstriction. The high training volumes require optimal nutrition with increased energy and dietary protein requirement to stimulate muscle protein synthesis response in the post-exercise period. Whether higher protein intake is required in the cold should be investigated. Cross-country skiing is performed mostly in Northern hemisphere with a strong cultural heritage and sporting tradition. It is expected that innovative initiatives on recruitment and training during the next few years will target to enhance performance of Chinese athletes in classical endurance-based winter sport. The innovation potential coupled with resourcing and population may be substantial with the potential for China to become a significant winter sport nation. This paper discusses the physiological aspects of endurance training and performance in winter sport highlighting areas where innovation may advance in athletic performance in cold environments. In addition, to ensure sustainable development of snow sport, a quality ski patrol and rescue system is recommended for the safety of increasing mass participation.

Die induzierbare laryngeale Obstruktion (ILO) – Ursachen, klinische Präsentation, Diagnostik und Therapie

Wiederholt episodenhaft auftretende Atemnot ist im Kindes- und Jugendalter ein häufiges Symptom. Neben anstrengungsinduzierter Bronchialobstruktion im Rahmen eines Asthma bronchiale ist eine funktionelle Genese eine sehr häufige Differenzialdiagnose. Dennoch wird diese Diagnose häufig nicht oder mit langer Latenz gestellt. Unter dem Oberbegriff „ILO“ („inducible laryngeal obstruction“) werden sowohl funktionelle supraglottische Obstruktionen durch Kollaps der Knorpelstrukturen als auch Dysfunktionen auf Glottisebene wie „vocal cord dysfunction“ (VCD) subsumiert. Körperliche Anstrengung ist ein häufiger Auslöser; es werden jedoch auch Beschwerdebilder ohne Anstrengungsbezug beobachtet. Es wird der Erkenntnisstand zur Pathophysiologie referiert und die klinische Präsentation beschrieben. Ein wesentlicher Fokus des Artikels liegt im Folgenden auf der Darstellung eines sinnvollen und Ressourcen-orientierten diagnostischen Vorgehens. Der CLE-Test („continuous laryngoscopy exercise test“) als Provokationsmethode unter Wach-Videolaryngoskopie ist der Goldstandard, jedoch wird diese Diagnostik im deutschsprachigen Raum nicht flächendeckend vorgehalten. Dieses Positionspapier stellt daher die diagnostische Wertigkeit verschiedener anderer Diagnostik-Algorithmen und anamnestischer Informationen heraus. Ein weiterer Schwerpunkt des Papiers besteht in der detaillierten Vorstellung geeigneter atemphysiotherapeutischer Interventionen.

Development and validation of the Exercise-Induced Laryngeal Obstruction Dyspnea Index (EILODI)

BACKGROUND

Exercise-induced laryngeal obstruction (EILO) causes exertional dyspnea and is important for its effect on quality of life, diagnostic confusion with exercise-induced asthma, and health care resource utilization. There is no validated patient-reported outcome measure specific to EILO.

OBJECTIVE

We sought to develop, validate, and define a minimal clinically important difference for a patient-reported outcome measure to be used with adolescents and young adults with EILO.

METHODS

A multidisciplinary group created a preliminary measure, modified by a 10-member participant focus group, with 20 items scored along a 5-point Likert scale. A subsequent cohort of participants recruited from a clinic, aged 12 to 21 years, with confirmed EILO by continuous laryngoscopy during exercise testing (1) completed the measure at 3 points in time over 28 days and (2) provided anchoring data in the form of a daily exercise log and categorical self-assessments of clinical improvement. Thirty additional participants without exertional dyspnea served as controls.

RESULTS

Two hundred nineteen subjects with mild to severe EILO participated in the exploratory factor analysis, which identified 7 factors within the preliminary outcome measure. After a process of item reduction, a 12-item metric with a total score ranging from 0 to 48 was developed. Mean scores of patients with EILO and healthy controls at baseline were 28.8 ± 7.4 and 4.5 ± 7.4, respectively. A minimal clinically important difference of 6 was determined by comparison of index change with changes in categorical self-assessments of improvement.

CONCLUSIONS

This is the first patient-reported outcome measure specifically designed for adolescents and young adults with EILO.

Characteristics and impact of exercise-induced laryngeal obstruction: an international perspective

Background

Exercise-induced laryngeal obstruction (EILO) is a common cause of exertional breathlessness and wheeze yet is frequently misdiagnosed as asthma. Insight regarding the demographic characteristics, laryngeal abnormalities and impact of EILO is currently limited, with data only available from individual centre reports. The aim of this work was to provide a broader perspective from a collaboration between multiple international expert centres.

Methods

Five geographically distinct clinical paediatric and adult centres (3 Denmark, 1 UK, 1 USA) with an expertise in assessing unexplained exertional breathlessness completed database entry of key characteristic features for all cases referred with suspected EILO over a 5-year period. All included cases completed clinical asthma workup and continuous laryngoscopy during exercise (CLE) testing for EILO.

Results

Data were available for 1007 individuals (n=713 female (71%)) with a median (range) age of 24 (8–76) years, and of these 586 (58%) were diagnosed with EILO. In all centres, EILO was frequently misdiagnosed as asthma; on average there was a 2-year delay to diagnosis of EILO, and current asthma medication was discontinued in 20%. Collapse at the supraglottic level was seen in 60%, whereas vocal cord dysfunction (VCD) was only detected/visualised in 18%. Nearly half (45%) of individuals with EILO were active participants in recreational-level sports, suggesting that EILO is not simply confined to competitive/elite athletes.

Conclusion

Our findings indicate that key clinical characteristics and the impact of EILO/VCD are similar in globally distinct regions, facilitating improved awareness of this condition to enhance recognition and avoid erroneous asthma treatment.

Exercise-induced laryngeal obstruction is a prevalent cause of exertional breathlessness and wheeze. In this international multicentre collaboration, 1007 patients waited, on average, 2 years for diagnosis and 20% were mistreated as asthmatic.https://bit.ly/3auXpcp

The benefits of a systematic assessment of respiratory health in illness-susceptible athletes

Respiratory tract illness is a leading cause of training and in-competition time loss in elite athletes. Asthma is known to be prevalent in athletes, but the coexistence of other respiratory problems in those deemed to be susceptible to respiratory tract illness is unknown. The aim of this study was to apply a comprehensive prospective approach to identify respiratory problems and explore relationships in athletes with heightened respiratory illness susceptibility.UK World Class Performance Programme athletes prospectively completed a systematic review of respiratory health with validated questionnaires and respiratory-focused investigations, including studies of nasal flow, exhaled nitric oxide, spirometry, bronchoprovocation testing and allergy testing.Systematic respiratory health assessment was completed by 122 athletes (55 females, mean±sd age 24±4 years). At least one respiratory health issue, requiring intervention, was identified in 97 (80%) athletes and at least two abnormalities were found in 73 (60%). Sinonasal problems were the most commonly identified problem (49%) and 22% of athletes had a positive indirect bronchoprovocation test. Analysis revealed two respiratory health clusters: 1) asthma, sinus problems and allergy; and 2) laryngeal and breathing pattern dysfunction. Respiratory illness susceptible athletes had 3.6±2.5 episodes in the year prior to assessment and were more likely to have allergy (OR 2.6, 95% CI 1.0-6.5), sinonasal problems (2.6, 1.1-6.0) and symptoms of laryngeal (5.4, 1.8-16.8) and breathing pattern dysfunction (3.9, 1.1-14.0) than nonsusceptible athletes (all p<0.05).A systematic approach to respiratory assessment identifies a high prevalence and coexistence of multiple respiratory problems in illness-susceptible athletes.

High Prevalence of Exercise-induced Laryngeal Obstruction in a Cohort of Elite Cross-country Skiers

INTRODUCTION

Exercise-induced laryngeal obstruction (EILO) is a differential diagnosis for asthma and prevalent in athletes referred for exercise-induced dyspnea. The aim of this study was to estimate the prevalence of EILO in elite cross-country skiers, known for a high prevalence of asthma.

METHOD

Elite cross-country skiers were invited for screening of EILO. Screening consisted of clinical assessment, questionnaires, skin prick test, spirometry, eucapnic voluntary hyperventilation test, and continuous laryngoscopy during exercise test. Current asthma was defined as physician-diagnosed asthma and use of asthma medication during the last 12 months. EILO was defined as ≥2 points at the supraglottic or glottic level during exercise at maximal effort, using a visual grade score system.

RESULT

A total of 89 (51% female) cross-country skiers completed the study. EILO was identified in 27% of the skiers, 83% of whom were female. All skiers with EILO had supraglottic EILO, and there was no glottic EILO. Current asthma was present in 34 (38%) of the skiers, 10 (29%) of whom had concomitant EILO. In the skiers with EILO, a higher proportion reported wheeze or shortness of breath after exercise, compared with skiers without EILO. In skiers with EILO and current asthma, compared with skiers with asthma only, a higher proportion reported wheeze or shortness of breath after exercise. Asthma medication usage did not differ between these groups.

CONCLUSION

EILO is common in elite cross-country skiers, especially females. Asthma and EILO may coexist, and the prevalence of respiratory symptoms is higher in skiers with both. Testing for EILO should be considered in cross-country skiers with respiratory symptoms.

The role of cardiopulmonary exercise testing in evaluating children with exercise induced dyspnoea

Exercise induced dyspnoea (EID) is a common manifestation in children and adolescents. Although EID is commonly attributed to exercise induced bronchoconstriction, several conditions other than asthma can cause EID in otherwise healthy children and adolescents. Cardiopulmonary exercise testing (CPET) offers a non-invasive comprehensive assessment of the cardiovascular, ventilatory and metabolic responses to exercise and is a powerful diagnostic and prognostic tool. CPET is a reproducible, non-invasive form of testing that allows for comparison against age- and gender-specific norms. CPET can assess the child's exercise capacity, determine the limiting factors associated with this, and be used to prescribe individualised interventions. EID can occur due to asthma, exercise induced laryngeal obstruction, breathing pattern disorders, chest wall restriction and cardiovascular pathology among other causes. Differentiating between these varied causes is important if effective therapy is to be initiated and quality of life improved in subjects with EID.

Exercise-induced laryngeal obstruction in children and adolescents: are we listening?

Exertional dyspnoea among children and adolescents is a common presenting complaint to general practitioners. Exertional dyspnoea is most commonly attributed to exercise-induced bronchoconstriction (EIB), but there are several other causes including hyperventilation syndrome, breathlessness associated with normal exercise limitation and exercise-induced laryngeal obstruction (EILO). The symptoms of EILO include stridor, throat tightness and difficulty on inspiration. If these are mistaken for EIB, children will receive asthma therapy. The underlying mechanism of EILO includes closure of the larynx during high-intensity exercise, which causes a reduction in airflow and breathlessness. This phenomenon is often associated with a background of psychological stress. Historically, a diagnosis of EILO has been considered 'rare' though this may be a reflection of under-recognition. Direct visual observation via laryngoscopy is the gold standard for diagnosis of EILO; however, this is rarely available even in specialised centres. Nevertheless, the diagnosis can usually be made by recognising the characteristic clinical pattern. Here we provide recommendations for appropriate investigations for the determination of EILO, together with suggested treatment.

Exercise-induced laryngeal obstruction: From clinical examination to continuous laryngoscopy during exercise

The diagnosis of exercise-induced laryngeal obstruction (EILO) should be suspected when exercise triggers inspiratory stridor. EILO is common in adolescent populations and has a significant impact on sports. Identification of laryngeal obstruction during continuous laryngoscopy during exercise (CLE) is the gold standard diagnostic tool for this disorder, which is not widely known in France. The challenge faced by otolaryngologists is to identify, among patients referred by pulmonologists or sports physicians, those with exercise-induced inspiratory symptoms or poorly controlled exercise-induced asthma, in whom a diagnosis of EILO is strongly suspected. Laryngoscopy at rest may reveal a laryngeal, glottic or supraglottic abnormality predictive of obstruction at increased inspiratory airflow. When pulmonary function tests are normal or in the case of failure of treatment of exercise-induced asthma, the otolaryngologist must complete the examination by a CLE test to confirm the diagnosis of EILO and identify the site of obstruction. This examination is well tolerated, minimally invasive and allows identification of the site of airflow obstruction, allowing specific conservative or surgical treatment. This technical note describes in detail clinical examination and CLE testing in patients with suspected EILO.

Reliability of maximum oxygen uptake in cardiopulmonary exercise testing with continuous laryngoscopy

Aims

A cardiopulmonary exercise test (CPET) is the gold standard to evaluate symptom-limiting exercise intolerance, while continuous laryngoscopy performed during exercise (CLE) is required to diagnose exercise-induced laryngeal obstruction. Combining CPET with CLE would save time and resources; however, the CPET data may be distorted by the extra equipment. We therefore aimed to study whether CPET with CLE influences peak oxygen uptake (V′_O2peak) and other gas exchange parameters when compared to a regular CPET.

Methods

Forty healthy athletes without exercise-related breathing problems, 15–35 years of age, performed CPET to peak exercise with and without an added CLE set-up, in randomised order 2–4 days apart, applying an identical computerised treadmill protocol.

Results

At peak exercise, the mean difference (95% confidence interval) between CPET with and without extra CLE set-up for V′_O2peak, respiratory exchange ratio (RER), minute ventilation (V′_E) and heart rate (HR) was 0.2 (−0.4 to 0.8) mL·kg⁻¹·min⁻¹, 0.01(−0.007 to 0.027) units, 2.6 (−1.3 to 6.5) L·min⁻¹ and 1.4 (−0.8 to 3.5) beats·min⁻¹, respectively. Agreement (95% limits of agreement) for V′_O2peak, RER and V′_E was 0.2 (±3.7) mL·kg⁻¹·min⁻¹, 0.01 (±0.10) units and 2.6 (±24.0) L·min⁻¹, respectively. No systematic or proportional bias was found except for the completed distance, which was 49 m (95% CI 16 to 82 m) longer during CPET.

Conclusion

Parameters of gas exchange, including V′_O2peak and RER, obtained from a maximal CPET performed with the extra CLE set-up can be used interchangeably with data obtained from standard CPET, thus preventing unnecessary additional testing.

Cardiopulmonary exercise testing (CPET) with concurrent continuous laryngoscopy provides reliable measures for maximal oxygen consumption and other CPET datahttps://bit.ly/36wVJhb

Exercise Related Respiratory Problems in the Young-Is It Exercise-Induced Bronchoconstriction or Laryngeal Obstruction?

Complaints of breathlessness during heavy exercise is common in children and adolescents, and represent expressions of a subjective feeling that may be difficult to verify and to link with specific diagnoses through objective tests. Exercise-induced asthma and exercise-induced laryngeal obstruction are two common medical causes of breathing difficulities in children and adolescents that can be challenging to distinguish between, based only on the complaints presented by patients. However, by applying a systematic clinical approach that includes rational use of tests, both conditions can usually be diagnosed reliably. In this invited mini-review, we suggest an approach we find feasible in our everyday clinical work.

Self-Reported Health in Adolescents With Exercise-Induced Laryngeal Obstruction; A Cross-Sectional Study

Background: Exercise-induced laryngeal obstruction (EILO) is common in young people with exertional breathing difficulties. Psychological characteristics have been proposed as underlying contributors; however, the evidence for this is limited. Objectives: Describe self-reported health, self-efficacy, and anxiety symptoms in adolescents with EILO, and address possible associations with EILO subtypes and severity. Methods: Cross-sectional study of 71/180 (39%) adolescents tested for EILO at Haukeland University Hospital during 2014-2016, age range 14-18 years. Validated questionnaires were used to assess general self-rated health, subjective health complaints (Health Behavior in School-aged Children-Symptom Check List; HBSC-SCL), general self-efficacy (GSE), and anxiety symptoms (SCARED). The outcomes were compared with normative data from comparable unselected populations. Results: The HBSC-SCL items for somatic complaints revealed weekly or more often occurrence of headache in 42%, abdominal pain in 30%, backache in 31%, and dizziness in 32%. For psychological complaints, corresponding figures were 26% for feeling low, 43% for irritability or bad mood, 33% for feeling nervous, and 38% for sleep problems. Mean (range) GSE score was 3.13 (2.2-4.0), and reports suggesting anxiety symptoms were rare. The outcomes were in line with normative data from comparable unselected populations. Self-rated health, and scores obtained for HBSC-SCL, GSE, and SCARED were similarly distributed across EILO subtypes and severity. Conclusion: Self-reported health, self-efficacy, and level of anxiety symptoms in adolescents with laryngoscopically confirmed EILO were similar to data obtained in comparable unselected populations, irrespective of EILO subtype and severity. The findings challenge the notion that pediatric EILO is causally related to psychological problems.

The Need for Testing-The Exercise Challenge Test to Disentangle Causes of Childhood Exertional Dyspnea

Exertional dyspnea is a common symptom in childhood which can induce avoidance of physical activity, aggravating the original symptom. Common causes of exertional dyspnea are exercise induced bronchoconstriction (EIB), dysfunctional breathing, physical deconditioning and the sensation of dyspnea when reaching the physiological limit. These causes frequently coexist, trigger one another and have overlapping symptoms, which can impede diagnoses and treatment. In the majority of children with exertional dyspnea, EIB is not the cause of symptoms, and in asthmatic children it is often not the only cause. An exercise challenge test (ECT) is a highly specific tool to diagnose EIB and asthma in children. Sensitivity can be increased by simulating real-life environmental circumstances where symptoms occur, such as environmental factors and exercise modality. An ECT reflects daily life symptoms and impairment, and can in an enjoyable way disentangle common causes of exertional dyspnea.

Reduced Asthma Medication Use after Treatment of Pediatric Paradoxical Vocal Fold Motion Disorder

OBJECTIVES/HYPOTHESES

The primary objective of this study was to determine whether the diagnosis and treatment of pediatric Paradoxical Vocal Fold Motion Disorder (PVFMD) leads to decreased asthma medication use. Our secondary objective was to determine dyspnea outcomes following diagnosis and treatment for PVFMD.

STUDY DESIGN

Prospective observational study.

METHODS

Patients with newly diagnosed PVFMD between the ages of 11 and 17 were recruited at a single pediatric institution. A medication questionnaire and Dyspnea Index (DI) were completed at the initial visit, at the first return visit, and at greater than 6 months post-diagnosis and therapy. Laryngeal Control Therapy (LCT) consisted of teaching breathing techniques and identifying emotional, physical, and environmental contributing factors and strategies to reduce them.

RESULTS

Twenty-six patients were recruited to the study. There were 19/26 (73%) patients diagnosed with asthma prior to a diagnosis of PVFMD, and 26/26 (100%) patients were using an inhaler prior to the enrollment visit. Twenty-two (85%) patients completed follow-up questionnaires. Five patients participated in no therapy, seven patients in partial therapy, and 14 patients in full therapy. Significant reduction in asthma medication use was seen in the full therapy group (P < .05) and in those with exercise as their only trigger (P < .05). Furthermore, symptoms as scored by the DI decreased overall from 25.5 to 18.8 (P < .001).

CONCLUSIONS

Diagnosis and treatment of pediatric PVFMD leads to a decline in asthma medication use in those patients who participate in at least two LCT sessions and in those with exercise-induced PVFMD. LCT for pediatric PVFMD leads to a significant decrease in symptoms as measured by the DI.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:1639-1646, 2021.

Prevalence of exercise-induced bronchoconstriction and laryngeal obstruction in adolescent athletes

OBJECTIVES

To study the prevalence of exercise-induced bronchoconstriction (EIB) and exercise-induced laryngeal obstruction (EILO) in adolescent athletes.

METHODS

All adolescents (n = 549) attending first year at a sports high school in 2016 and 2017, were invited to answer a questionnaire on respiratory symptoms. The 367 responding participants were divided into two groups based on whether they reported exercise-induced dyspnea (dyspnea group) or not (nondyspnea group). Randomly selected participants in each group were invited to undergo two standardized exercise tests, an EIB test and a continuous laryngoscopy exercise (CLE) test, to investigate EILO.

RESULTS

In total, 98 participants completed an EIB test, 75 of whom also completed a CLE test. Positive EIB tests: eight of 41 in the dyspnea group and 16 of 57 in the nondyspnea group. Positive CLE tests: 5 of 34 in the dyspnea group and three of 41 in the nondyspnea group. The estimated prevalence of EIB was 23.1% (95% confidence interval [CI]: 14.5-33.8) and of EILO 8.1% (95% CI: 2.5-18.5) in the whole study population. No differences in prevalence of EIB or EILO were found between the dyspnea and the nondyspnea groups.

CONCLUSION

EIB was highly prevalent in this cohort of adolescent athletes. EILO was less prevalent, but represents an important differential diagnosis to EIB. Self-reported exercise-induced dyspnea is a weak indicator for both EIB and EILO and standardized testing should be provided.

The interest of rehabilitation of respiratory disorders in athletes: Myth or reality?

BACKGROUND

Healthy trained athletes generally have an "overbuilt" respiratory system in order to face the huge ventilation and gas-exchange demand imposed by strenuous exercise. Athletes frequently complain of respiratory symptoms regardless of whether they have a diagnosed respiratory disease, therefore evoking a kind of respiratory limitation during exercise. Some respiratory pathologies athletes present are closely linked to exercise and include asthma, exercise-induced bronchoconstriction (EIB) or exercise-induced laryngeal obstruction. Management of asthma and EIB are mainly based on pharmacological treatments. However, many athletes still complain of respiratory symptoms despite optimal pharmacological treatments, which highlights the need for non-pharmacological approaches including breathing retraining, inspiratory muscle training and/or laryngeal exercise performed under the guidance of a physiotherapist in this specific population.

OBJECTIVES

With this literature overview, we aimed to report evidence supporting the interest of rehabilitation for athletes with respiratory disorders and discuss whether inspiratory muscle training programs can improve performance in healthy athletes.

METHODS

We searched MEDLINE and Cochrane databases for trials, reviews and meta-analyses assessing respiratory rehabilitation and muscle training programs in athletes by using the MesH terms "athletes", "asthma", "dyspnea", "rehabilitation" and "education" published from January 2010 to March 2020. The selection of articles was based on the author's expertise to elaborate this review of the literature.

RESULTS

Major findings suggest that breathing retraining may help asthmatic athletes better control their respiratory symptoms and that inspiratory muscle training may improve respiratory symptoms of exercise-induced laryngeal obstruction in athletes. Improvement of performance by respiratory muscle training still remains controversial.

CONCLUSIONS

Respiratory rehabilitation could be of interest in the specific population of athletes but should be further evaluated to improve the level of evidence of such strategies.

Asthma in Competitive Cross-Country Skiers: A Systematic Review and Meta-analysis

INTRODUCTION

In cross-country skiing, the repetitive ventilation of large amounts of cold and dry air strains the airways. The aim of this systematic review was to establish an overview of the current literature on asthma in cross-country skiers, biathletes and ski-orienteers.

METHODS

Six databases were searched on August 29, 2019. The search yielded 2161 articles. Thirty articles fulfilled the search criteria and were pooled together for a qualitative synthesis. Eight articles were included in the meta-analysis on the prevalence of asthma and the use of asthma medication.

RESULTS

According to the meta-analysis, the prevalence of self-reported physician-diagnosed asthma in skiers was 21% (95% CI 14-28%). The onset age of asthma was higher in skiers than in non-skiers with asthma. The prevalence of asthma medication use was on average 23% (CI 95% 19-26%). Several studies reported that asthma was underdiagnosed in skiers, as previously healthy skiers without a prior asthma diagnosis or medication use were frequently found to fulfill diagnostic criteria for asthma according to lung function tests. Studies using bronchial biopsy demonstrated that eosinophilic asthma is not detected in skiers with asthma as often as it is in non-skiers with asthma and that there are signs of airway inflammation even in non-asthmatic skiers.

CONCLUSION

Our findings suggest that the accuracy and coverage of diagnosing asthma in skiers has improved over the recent decades. However, the optimal treatment and natural course of asthma in this population remain unclear. Future research should investigate how the intensity of training, airway infections and their treatment affect the development of asthma among skiers.

PRD REGISTRATION NUMBER

CRD42017070940.

High prevalence of exercise-induced stridor during Parkrun: a cross-sectional field-based evaluation

BACKGROUND AND OBJECTIVE

The differential diagnosis for exercise-associated breathlessness is broad, however, when a young athletic individual presents with respiratory symptoms, they are most often prescribed inhaler therapy for presumed exercise-induced asthma (EIA). The purpose of this study was therefore to use a novel sound-based approach to assessment to evaluate the prevalence of exertional respiratory symptoms and characterise abnormal breathing sounds in a large cohort of recreationally active individuals.

METHODS

Cross-sectional field-based evaluation of individuals completing Parkrun. PHASE 1: Prerace, clinical assessment and baseline spirometry were conducted. At peak exercise and immediately postrace, breathing was monitored continuously using a smartphone. Recordings were analysed retrospectively and coded for signs of the predominant respiratory noise. PHASE 2: A subpopulation that reported symptoms with at least one audible sign of respiratory dysfunction was randomly selected and invited to attend the laboratory on a separate occasion to undergo objective clinical workup to confirm or refute EIA.

RESULTS

Forty-eight participants (22.6%) had at least one audible sign of respiratory dysfunction; inspiratory stridor (9.9%), expiratory wheeze (3.3%), combined stridor+wheeze (3.3%), cough (6.1%). Over one-third of the cohort (38.2%) were classified as symptomatic. Ten individuals attended a follow-up appointment, however, only one had objective evidence of EIA.

CONCLUSIONS

The most common audible sign, detected in approximately 1 in 10 individuals, was inspiratory stridor, a characteristic feature of upper airway closure occurring during exercise. Further work is now required to further validate the precision and feasibility of this diagnostic approach in cohorts reporting exertional breathing difficulty.

Reported Symptoms Differentiate Diagnoses in Children with Exercise-Induced Respiratory Problems: Findings from the Swiss Paediatric Airway Cohort (SPAC)

BACKGROUND

Exercise-induced breathing problems with similar clinical presentations can have different etiologies. This makes distinguishing common diagnoses such as asthma, extrathoracic and thoracic dysfunctional breathing (DB), insufficient fitness, and chronic cough difficult.

OBJECTIVE

We studied which parent-reported, exercise-induced symptoms can help distinguish diagnoses in children seen in respiratory outpatient clinics.

METHODS

This study was nested in the Swiss Paediatric Airway Cohort, an observational study of children aged 0 to 17 years referred to pediatric respiratory outpatient clinics in Switzerland. We studied children aged 6 to 17 years and compared information on exercise-induced symptoms from parent-completed questionnaires between children with different diagnoses. We used multinomial regression to analyze whether parent-reported symptoms differed between diagnoses (asthma as base).

RESULTS

Among 1109 children, exercise-induced symptoms were reported for 732 (66%) (mean age: 11 years, 318 of 732 [43%] female). Among the symptoms, dyspnea best distinguished thoracic DB (relative risk ratio [RRR]: 5.4, 95% confidence interval [CI]: 1.3-22) from asthma. Among exercise triggers, swimming best distinguished thoracic DB (RRR: 2.4, 95% CI: 1.3-6.2) and asthma plus DB (RRR: 1.8, 95% CI: 0.9-3.4) from asthma only. Late onset of symptoms was less common for extrathoracic DB (RRR: 0.1, 95% CI: 0.03-0.5) and thoracic DB (RRR: 0.4, 95% CI: 0.1-1.2) compared with asthma. Localization of dyspnea (throat vs chest) differed between extrathoracic DB (RRR: 2.3, 95% CI: 0.9-5.8) and asthma. Reported respiration phase (inspiration or expiration) did not help distinguish diagnoses.

CONCLUSION

Parent-reported symptoms help distinguish different diagnoses in children with exercise-induced symptoms. This highlights the importance of physicians obtaining detailed patient histories.

Is the healthy respiratory system built just right, overbuilt, or underbuilt to meet the demands imposed by exercise?

In the healthy, untrained young adult, a case is made for a respiratory system (airways, pulmonary vasculature, lung parenchyma, respiratory muscles, and neural ventilatory control system) that is near ideally designed to ensure a highly efficient, homeostatic response to exercise of varying intensities and durations. Our aim was then to consider circumstances in which the intra/extrathoracic airways, pulmonary vasculature, respiratory muscles, and/or blood-gas distribution are underbuilt or inadequately regulated relative to the demands imposed by the cardiovascular system. In these instances, the respiratory system presents a significant limitation to O₂ transport and contributes to the occurrence of locomotor muscle fatigue, inhibition of central locomotor output, and exercise performance. Most prominent in these examples of an "underbuilt" respiratory system are highly trained endurance athletes, with additional influences of sex, aging, hypoxic environments, and the highly inbred equine. We summarize by evaluating the relative influences of these respiratory system limitations on exercise performance and their impact on pathophysiology and provide recommendations for future investigation.

Struggling to Breathe: Inspiratory Muscle Training in Adolescent Athletes

OBJECTIVE

Dyspnea is a primary characteristic of exercise-induced laryngeal obstruction and prevents individuals from inhaling and exhaling without effort. This single subject research study investigated the effects of inspiratory muscle training (IMT) on exercise-induced symptoms characteristic of exercise-induced laryngeal obstruction in adolescent athletes.

METHODS

Five weeks of IMT was provided to five adolescent athletes, four females and one male, aged 10 to 16. Variables that were measured prior to, during, and after completion of IMT program included maximum phonation time, maximum perceived breathlessness, duration of running, and quality of life regarding dyspnea.

RESULTS

Results showed a reduction in maximum perceived breathlessness as well as a significant increase in maximum phonation time across participants. The majority of participants rated their quality of life regarding dyspnea as significant improved after IMT.

CONCLUSIONS

These findings contribute to the increasing body of literature investigating the use of alternative therapy strategies for treatment of symptoms of exercise-induced laryngeal obstruction in adolescent athletes.