Exercise-induced bronchoconstriction in athletes - A qualitative assessment of symptom perception

Fractional exhaled nitric oxide in the assessment of exercise-induced bronchoconstriction: A multicenter retrospective analysis of UK-based athletes

INTRODUCTION

Exercise-induced bronchoconstriction (EIB) is not only highly prevalent in people with asthma, but can also occur independently, particularly in athletes. Fractional exhaled nitric oxide (FeNO) is an indirect biomarker of type 2 airway inflammation that has an established role in the assessment and management of asthma. The aim was to evaluate the value of FeNO in the assessment of EIB in athletes.

METHOD

Multicenter retrospective analysis. In total, 488 athletes (male: 76%) performed baseline FeNO, and spirometry pre- and post-indirect bronchial provocation via eucapnic voluntary hyperpnea (EVH). Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for established FeNO thresholds-that is, intermediate (≥25 ppb) and high FeNO (≥40 ppb and ≥ 50 ppb)-and were evaluated against objective evidence of EIB (≥10% fall in FEV₁ ). The diagnostic accuracy of FeNO was calculated using receiver operating characteristics area under the curve (ROC-AUC).

RESULTS

Thirty-nine percent of the athletes had a post-EVH fall in FEV₁ consistent with EIB. FeNO values ≥25 ppb, ≥40 ppb, and ≥ 50 ppb were observed in 42%, 23%, and 17% of the cohort, respectively. The sensitivity of FeNO ≥25 ppb was 55%, which decreased to 37% and 27% at ≥40 ppb and ≥ 50 ppb, respectively. The specificity of FeNO ≥25 ppb, ≥40 ppb, and ≥ 50 ppb was 66%, 86%, and 89%, respectively. The ROC-AUC for FeNO was 0.656.

CONCLUSIONS

FeNO ≥40 ppb provides good specificity, that is, the ability to rule-in a diagnosis of EIB. However, due to the poor sensitivity and predictive values, FeNO should not be employed as a replacement for indirect bronchial provocation in athletes.

Diagnostic approach to lower airway dysfunction in athletes: a systematic review and meta-analysis by a subgroup of the IOC consensus on 'acute respiratory illness in the athlete'

OBJECTIVES

To compare the performance of various diagnostic bronchoprovocation tests (BPT) in the assessment of lower airway dysfunction (LAD) in athletes and inform best clinical practice.

DESIGN

Systematic review with sensitivity and specificity meta-analyses.

DATA SOURCES

PubMed, EBSCOhost and Web of Science (1 January 1990-31 December 2021).

ELIGIBILITY CRITERIA

Original full-text studies, including athletes/physically active individuals (15-65 years) who underwent assessment for LAD by symptom-based questionnaires/history and/or direct and/or indirect BPTs.

RESULTS

In 26 studies containing data for quantitative meta-analyses on BPT diagnostic performance (n=2624 participants; 33% female); 22% had physician diagnosed asthma and 51% reported LAD symptoms. In athletes with symptoms of LAD, eucapnic voluntary hyperpnoea (EVH) and exercise challenge tests (ECTs) confirmed the diagnosis with a 46% sensitivity and 74% specificity, and 51% sensitivity and 84% specificity, respectively, while methacholine BPTs were 55% sensitive and 56% specific. If EVH was the reference standard, the presence of LAD symptoms was 78% sensitive and 45% specific for a positive EVH, while ECTs were 42% sensitive and 82% specific. If ECTs were the reference standard, the presence of LAD symptoms was 80% sensitive and 56% specific for a positive ECT, while EVH demonstrated 65% sensitivity and 65% specificity for a positive ECT.

CONCLUSION

In the assessment of LAD in athletes, EVH and field-based ECTs offer similar and moderate diagnostic test performance. In contrast, methacholine BPTs have lower overall test performance.

PROSPERO REGISTRATION NUMBER

CRD42020170915.

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.

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.

Dyspnoea-12 and Multidimensional Dyspnea Profile: Systematic Review of Use and Properties

CONTEXT

The Dyspnoea-12 (D-12) and Multidimensional Dyspnea Profile (MDP) were specifically developed for assessment of multiple sensations of breathlessness.

OBJECTIVES

This systematic review aimed to identify the use and measurement properties of the D-12 and MDP across populations, settings and languages.

METHODS

Electronic databases were searched for primary studies (2008-2020) reporting use of the D-12 or MDP in adults. Two independent reviewers completed screening and data extraction. Study and participant characteristics, instrument use, reported scores and minimal clinical important differences (MCID) were evaluated. Data on internal consistency (Cronbach's α) and test-retest reliability (intraclass correlation coefficient, ICC) were pooled using random effects models between settings and languages.

RESULTS

A total 75 publications reported use of D-12 (n = 35), MDP (n = 37) or both (n = 3), reflecting 16 chronic conditions. Synthesis confirmed two factor structure, internal consistency (Cronbach's α mean, 95% CI: D-12 Total = 0.93, 0.91-0.94; MDP Immediate Perception [IP] = 0.88, 0.85-0.90; MDP Emotional Response [ER] = 0.86, 0.82-0.89) and 14 day test-rest reliability (ICC: D-12 Total = 0.91, 0.88-0.94; MDP IP = 0.85, 0.70-0.93; MDP ER = 0.84, 0.73-0.90) across settings and languages. MCID estimates for clinical interventions ranged between -3 and -6 points (D-12 Total) with small variability in scores over 2 weeks (D-12 Total 2.8 (95% CI: 2.0 to 3.7), MDP-A1 0.8 (0.6 to 1.1) and six months (D-12 Total 2.9 (2.0 to 3.7), MDP-A1 0.8 (0.6 to 1.1)).

CONCLUSION

D-12 and MDP are widely used, reliable, valid and responsive across various chronic conditions, settings and languages, and could be considered standard instruments for measuring dimensions of breathlessness in international trials.

Incremental shuttle walk test: is it able to detect exercise-induced bronchospasm in young adult asthmatics?

OBJECTIVE

To determine the accuracy of incremental Shuttle Walking Test (ISWT) in detecting exercise-induced bronchospasm (EIB) in adults with asthma and to verify whether there is an association of the drop in FEV₁ between ISWT and cardiopulmonary exercise testing with constant-load CPET-CL.

METHODS

In this cross-sectional study 32 individuals with asthma performed two ISWTs, an incremental cardiopulmonary exercise test (CPET-I) and a constant-load cardiopulmonary exercise test (CPET-CL) with na interval of 48 h between tests. Spirometric measurements were obtained 5, 10, 15, 20 and 30 min after exercise; an FEV1 decline > 10% was considered EIB.

RESULTS

Fifteen individuals had EIB in both tests [χ2 = 9.41; κ = 0.46 p < 0.002 (95% CI: 0.201-0.708)], with moderate agreement. There was a significant correlation between the greatest variation in the drop in FEV₁ between the ISWT and the CPET-CL (r = 0.48; p < 0.01). There was a significant difference for ventilation maintenance time above 40% of Maximum Voluntary Ventilation between the groups of positive EIB (p = 0.001) and negative EIB (p = 0.001) and for ventilatory demand (positive EIB group) (p = 0.008) between ISWT vs CPET-CL. Moreover, assuming CPET-CL as the criterion test, ISWT presented a sensitivity of 62.5% and specificity was 100%.

CONCLUSION

ISWT showed moderate accuracy in detecting EIB in adults with asthma and was able to show similar metabolic and ventilatory demand presented in CPET-CL.

Asthma medication in athletes: a qualitative investigation of adherence, avoidance and misuse in competitive sport

OBJECTIVES

The purpose of this qualitative study was to utilize the Capability, Opportunity, Motivation - Behavior model (COM-B) to: (1) evaluate athlete knowledge and understanding of current asthma-related anti-doping regulations, (2) explore the impact of environmental and societal influences on athletes with asthma, and (3) examine athlete perception of asthma medication use in competitive sport.Methods: Semi-structured interviews were conducted with ten competitive endurance athletes (five athletes with asthma and five without asthma). Interviews were guided by the COM-B model and transcripts were analyzed inductively and deductively using reflexive thematic analysis.Results: Mapping the experiences and perceptions of athletes against an established behavioral framework identified that: (1) athletes' possess limited knowledge and understanding of the World Anti-Doping Agency (WADA) Prohibited List and Therapeutic use exemption (TUE) policy with respect to asthma medication; (2) the use of sub-optimal diagnostic methods is commonplace and increases the risk of misdiagnosis and unnecessary inhaler therapy; (3) negative media portrayal of high-profile asthma-related doping allegations impacts public opinion and contributes to the perception of wrongdoing within the sporting community.Conclusion: The novel application of behavioral science highlights several factors that may contribute to asthma medication avoidance and promote misuse in competitive sport. The findings from this study provide a foundation for the development and implementation of targeted education programmes, and it is hoped that employing this approach will ultimately improve overall perceptions of asthma treatment in athletes, which is necessary to maintain respiratory health, optimize performance and protect the integrity of sport.

© 2021 The Author(s). Published with license by Taylor & Francis Group, LLC.

Respiratory impact of a grand tour: insight from professional cycling

PURPOSE

The aim of this study was to evaluate the respiratory function and symptom perception in professional cyclists completing a Grand Tour (GT).

METHODS

Nine male cyclists completed La Vuelta or Tour de France (2018/19). At study entry, airway inflammation was measured via fractional exhaled nitric oxide (FeNO). Respiratory symptoms and pulmonary function were assessed prior to the first stage (Pre-GT), at the second rest day (Mid-GT) and prior to the final stage of the GT (Late-GT). Sniff nasal inspiratory pressure (SNIP) was assessed at pre and late-GT timepoints.

RESULTS

Seven cyclists reported respiratory symptoms during the race (with a prominence of upper airway issues). Symptom severity increased either mid or late-GT for most cyclists. A decline in FEV₁ from pre-to-mid GT (- 0.27 ± 0.24 l, - 5.7%) (P = 0.02) and pre-to-late GT (- 0.27 ± 0.13 l, - 5.7%) (P < 0.001) was observed. Similarly, a decline in FVC (- 0.22 ± 0.17 l, - 3.7%) (P = 0.01) and FEF_25-75 (- 0.49 ± 0.34 l/s, - 11%) (P = 0.02) was observed pre-to-late GT. Overall, eight (89%) and six (67%) demonstrated a clinically meaningful decline (> 200 ml) in FEV₁ and FVC during the GT follow-up, respectively. SNIP remained unchanged pre-to-late GT (n = 5), however, a positive correlation was observed between ΔSNIP and ΔFVC (r = 0.99, P = 0.002).

CONCLUSION

GT competition is associated with a high prevalence of upper respiratory symptoms and a meaningful decline in lung function in professional cyclists. Further research is now required to understand the underpinning physiological mechanisms and determine the impact on overall respiratory health and elite cycling performance and recovery.

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.

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.

Anti-muscarinic drugs as preventive treatment of exercise-induced bronchoconstriction (EIB) in children and adults

Regular physical activity is strongly recommended to prevent chronic respiratory diseases, including asthma. On the other hand, vigorous physical training may trigger airway symptoms and bronchoconstriction. The transient airway narrowing occurring because of exercise is named exercise-induced bronchoconstriction (EIB). Despite management according to guidelines, a significant proportion of patients experiences uncontrolled EIB, which thus represents a relevant unmet medical need. In particular, although prevention and treatment of EIB are effectively based on the use of beta-2 bronchodilator drugs, high heterogeneity in individual responses has been reported. Furthermore, even though beta-2 adrenergic drugs remain the mainstay of EIB management, occurrence of tolerance and side effects, as well as doping concerns have been reported with their use. In regard to this, inhaled antimuscarinics could represent an alternative or additional effective and safe bronchodilator therapeutic option for achieving optimal EIB control and minimize adverse events. The present systematic review aims to collect and provide the most updated and evidence-based literature findings on the efficacy and safety of short- and long-acting inhaled anti-muscarinic drugs for the preventive treatment of EIB in both children and adults. Take-Home Message: Anti-muscarinic drugs are effective and safe in preventing EIB, despite response variability is reported. Further studies should focus on long-acting molecules, chronic administration and phenotype-driven effects.

Anti-doping Policy, Therapeutic Use Exemption and Medication Use in Athletes with Asthma: A Narrative Review and Critical Appraisal of Current Regulations

Asthma is prevalent in athletes and when untreated can impact both respiratory health and sports performance. Pharmacological inhaler therapy currently forms the mainstay of treatment; however, for elite athletes competing under the constraints of the World Anti-Doping Code (Code), a number of established therapies are prohibited both in and/or out of competition and/or have a maximum permitted dose. The recent release of medical information detailing inhaler therapy in high-profile athletes has brought the legitimacy and utilisation of asthma medication in this setting into sharp focus. This narrative review critically appraises recent changes to anti-doping policy and the Code in the context of asthma management, evaluates the impact of asthma medication use on sports performance and employs a theory of behaviour to examine perceived determinants and barriers to athletes adhering to the anti-doping rules of sport when applied to asthma.

Special Considerations and Perspectives for Exercise-Induced Bronchoconstriction (EIB) in Olympic and Other Elite Athletes

Diagnosing and treating elite and Olympic athletes with exercise-induced bronchoconstriction has been well established. However, a subset of elite and Olympic athletes with exercise-induced bronchoconstriction experience symptoms of breathlessness due to lack of adherence, improper medications, and/or generalized breathing dysfunction. A short review of traditional treatment plans for elite and Olympic athletes is presented along with the challenges of adherence, managing dysfunctional breathing, and measuring and treating mental skills deficits that may impact breathing. Elite and Olympic athletes may not respond to traditional treatment for exercise-induced bronchospasm, and we present some of the reasons why the athletes fail to respond. Furthermore, we present information on how to detect and treat elite and Olympic athletes with difficult-to-treat asthma. As part of this review we developed a flow diagram for medical providers to identify the reasons for lack of response to traditional treatment plans for exercise-induced bronchoconstriction with options for other treatment modalities.

A vascular cause of unexplained exertional wheeze: Keeping a high index of suspicion

A 31-year-old female was referred with a history of unexplained exertional breathlessness. The patient had normal resting lung function and a CT thorax showed no significant abnormality. Closer scrutiny of the flow-volume loop confirmed an elevated Empey's index. Cardiopulmonary exercise testing with continuous laryngoscopy was conducted to evaluate the upper airway response to exercise which confirmed loud biphasic wheeze. A bronchoscopy revealed no stenosis nor intraluminal narrowing, however, a contrast CT confirmed a right-sided aortic arch and aberrant left subclavian artery. Following multidisciplinary review, the patient opted for a surgical approach to treatment however despite initially reporting an improvement in symptoms and exercise capacity continued to suffer exertional wheeze two-years post-surgery. This clinical report describes a rare vascular cause of exertional wheeze but also provides a cautionary note in terms of providing a guarded prognosis for adults undergoing surgical intervention for tracheal compression arising from congenital vascular abnormalities.

Let research leave you breathless, not physical exercise!

Regular physical activity is strongly recommended by healthcare systems worldwide and evidence-based guidelines and is one of the most effective approaches for preventing chronic inflammatory diseases and maintaining health status [1]. Indeed, extensive evidence exists on the beneficial effect of physical training and rehabilitation programmes in asthma [2]. Physical activity has been shown to improve quality of life, exercise capacity, pulmonary function and symptoms, as well as reduce airway inflammation and bronchial responsiveness in patients with asthma [3–5]. However, intense physical exercise may trigger airway narrowing by imposing a high demand on the respiratory system, requiring subjects to ventilate primarily through the mouth and by-pass the nasal filter, with a subsequent increased pulmonary exposure to inhalant allergens, pollutants, irritants and adverse (i.e. cold, dry) environmental conditions [6]. Such airway narrowing, which transiently occurs as a result of exercise, is defined as exercise-induced bronchoconstriction (EIB) [7]. Interestingly, in a 5-year prospective study, subjects who stopped training experienced an attenuation, or in some circumstances disappearance, of EIB, whereas bronchial responsiveness, exercise-induced respiratory symptoms and eosinophilic airway inflammation increased amongst those who continued strenuous physical exercise, regardless of the pharmacological treatment strategies [8]. Put into context, ongoing intense training appears to be a causative, and not just a concomitant, factor of airway inflammation and narrowing.

Proper endotyping of EIB and precision medicine strategies would allow subjects to fully profit from the very beneficial effects of exercise, without incurring health risks or affecting performanceshttp://ow.ly/spjT30irzjX

Exercise-Induced Bronchoconstriction: Background, Prevalence, and Sport Considerations

The transient airway narrowing that occurs as a result of exercise is defined as exercise-induced bronchoconstriction (EIB). The prevalence of EIB has been reported to be up to 90% in asthmatic patients, reflecting the level of disease control. However, EIB may develop even in subjects without clinical asthma, particularly in children, athletes, patients with atopy or rhinitis, and following respiratory infections. The intensity, duration, and type of training have been associated with the occurrence of EIB. In athletes, EIB seems to be only partly reversible, and exercise seems to be a causative factor of airway inflammation and symptoms.