Exercise-induced asthma: diagnosis and management

GEMA 5.3. Spanish Guideline on the Management of Asthma

The Spanish Guideline on the Management of Asthma, better known by its acronym in Spanish GEMA, has been available for more than 20 years. Twenty-one scientific societies or related groups both from Spain and internationally have participated in the preparation and development of the updated edition of GEMA, which in fact has been currently positioned as the reference guide on asthma in the Spanish language worldwide. Its objective is to prevent and improve the clinical situation of people with asthma by increasing the knowledge of healthcare professionals involved in their care. Its purpose is to convert scientific evidence into simple and easy-to-follow practical recommendations. Therefore, it is not a monograph that brings together all the scientific knowledge about the disease, but rather a brief document with the essentials, designed to be applied quickly in routine clinical practice. The guidelines are necessarily multidisciplinary, developed to be useful and an indispensable tool for physicians of different specialties, as well as nurses and pharmacists. Probably the most outstanding aspects of the guide are the recommendations to: establish the diagnosis of asthma using a sequential algorithm based on objective diagnostic tests; the follow-up of patients, preferably based on the strategy of achieving and maintaining control of the disease; treatment according to the level of severity of asthma, using six steps from least to greatest need of pharmaceutical drugs, and the treatment algorithm for the indication of biologics in patients with severe uncontrolled asthma based on phenotypes. And now, in addition to that, there is a novelty for easy use and follow-up through a computer application based on the chatbot-type conversational artificial intelligence (ia-GEMA).

Japanese guidelines for adult asthma 2020

Bronchial asthma is characterized by chronic airway inflammation, which manifests clinically as variable airway narrowing (wheezes and dyspnea) and cough. Long-standing asthma may induce airway remodeling and become intractable. The prevalence of asthma has increased; however, the number of patients who die from it has decreased (1.3 per 100,000 patients in 2018). The goal of asthma treatment is to control symptoms and prevent future risks. A good partnership between physicians and patients is indispensable for effective treatment. Long-term management with therapeutic agents and the elimination of the triggers and risk factors of asthma are fundamental to its treatment. Asthma is managed by four steps of pharmacotherapy, ranging from mild to intensive treatments, depending on the severity of disease; each step includes an appropriate daily dose of an inhaled corticosteroid, which may vary from low to high. Long-acting β₂-agonists, leukotriene receptor antagonists, sustained-release theophylline, and long-acting muscarinic antagonists are recommended as add-on drugs, while anti-immunoglobulin E antibodies and other biologics, and oral steroids are reserved for very severe and persistent asthma related to allergic reactions. Bronchial thermoplasty has recently been developed for severe, persistent asthma, but its long-term efficacy is not known. Inhaled β₂-agonists, aminophylline, corticosteroids, adrenaline, oxygen therapy, and other approaches are used as needed during acute exacerbations, by selecting treatment steps for asthma based on the severity of the exacerbations. Allergic rhinitis, eosinophilic chronic rhinosinusitis, eosinophilic otitis, chronic obstructive pulmonary disease, aspirin-exacerbated respiratory disease, and pregnancy are also important conditions to be considered in asthma therapy.

Exercise-induced bronchoconstriction, temperature regulation and the role of heat shock proteins in non-asthmatic recreational marathon and half-marathon runners

Exercise is the most common trigger of bronchospasm. Heat shock protein (HSP) expression was linked to asthmatic patients. The prevalence and pathophysiology of exercise-induced bronchoconstriction (EIB) in non-professional non-asthmatic runners is unknown. We sought to investigate the frequency of EIB and cytokine changes in non-professional non-asthmatic marathon and half marathoners with and without EIB. Testing was performed before the marathon (baseline), immediately post-marathon at the finish area (peak), and 2–7 days after the marathon (recovery): immunosorbent assays for measurement of HSP70, blood count analysis, spirometry and temperature measurements. We experienced a decline in FEV1 of ≥10% in 35.29% of marathon and 22.22% of half marathon runners. Runners with EIB had significantly higher HSP70 serum concentrations at baseline than those without EIB (987.4 ± 1486.7 vs. 655.6 ± 1073.9; p = 0.014). Marathoners with EIB had significantly increased WBC before participating in the competition (7.4 ± 1.7 vs. 6.0 ± 1.5; p = 0.021). After recovery we found increased HSP70 serum concentrations in marathoners with EIB compared to those without (2539.2 ± 1692.5 vs. 1237.2 ± 835.2; p = 0.032), WBC (7.6 ± 1.8 vs. 6.4 ± 1.6; p = 0.048) and PLT (273.0 ± 43.0 vs 237.2 ± 48.3; p = 0.040). At all measured skin sites skin temperatures in runners were significantly lower immediately after participating in the competition when compared to temperature before the race (skin temperature baseline vs. peak: abdominal: 33.1 ± 0.2 vs. 30.0 ± 0.4; p < 0.001; upper arm: 31.6 ± 0.2 vs. 29.4 ± 0.3; p < 0.001; upper leg: 30.7 ± 0.3 vs. 29.4 ± 0.2; p = 0.014; lower leg: 30.6 ± 1.0 vs. 30.2 ± 1.5; p = 0.007). We found a higher than expected number of non-professional athletes with EIB. HSP70 serum concentrations and elevated WBC could indicate a predisposition to EIB.

Exercise-induced bronchoconstriction update-2016

The first practice parameter on exercise-induced bronchoconstriction (EIB) was published in 2010. This updated practice parameter was prepared 5 years later. In the ensuing years, there has been increased understanding of the pathogenesis of EIB and improved diagnosis of this disorder by using objective testing. At the time of this publication, observations included the following: dry powder mannitol for inhalation as a bronchial provocation test is FDA approved however not currently available in the United States; if baseline pulmonary function test results are normal to near normal (before and after bronchodilator) in a person with suspected EIB, then further testing should be performed by using standardized exercise challenge or eucapnic voluntary hyperpnea (EVH); and the efficacy of nonpharmaceutical interventions (omega-3 fatty acids) has been challenged. The workgroup preparing this practice parameter updated contemporary practice guidelines based on a current systematic literature review. The group obtained supplementary literature and consensus expert opinions when the published literature was insufficient. A search of the medical literature on PubMed was conducted, and search terms included pathogenesis, diagnosis, differential diagnosis, and therapy (both pharmaceutical and nonpharmaceutical) of exercise-induced bronchoconstriction or exercise-induced asthma (which is no longer a preferred term); asthma; and exercise and asthma. References assessed as relevant to the topic were evaluated to search for additional relevant references. Published clinical studies were appraised by category of evidence and used to document the strength of the recommendation. The parameter was then evaluated by Joint Task Force reviewers and then by reviewers assigned by the parent organizations, as well as the general membership. Based on this process, the parameter can be characterized as an evidence- and consensus-based document.

Exercise as medicine - evidence for prescribing exercise as therapy in 26 different chronic diseases

This review provides the reader with the up-to-date evidence-based basis for prescribing exercise as medicine in the treatment of 26 different diseases: psychiatric diseases (depression, anxiety, stress, schizophrenia); neurological diseases (dementia, Parkinson's disease, multiple sclerosis); metabolic diseases (obesity, hyperlipidemia, metabolic syndrome, polycystic ovarian syndrome, type 2 diabetes, type 1 diabetes); cardiovascular diseases (hypertension, coronary heart disease, heart failure, cerebral apoplexy, and claudication intermittent); pulmonary diseases (chronic obstructive pulmonary disease, asthma, cystic fibrosis); musculo-skeletal disorders (osteoarthritis, osteoporosis, back pain, rheumatoid arthritis); and cancer. The effect of exercise therapy on disease pathogenesis and symptoms are given and the possible mechanisms of action are discussed. We have interpreted the scientific literature and for each disease, we provide the reader with our best advice regarding the optimal type and dose for prescription of exercise.

Medical and pharmacological approach to adjust the salbutamol anti-doping policy in athletes

BACKGROUND

Salbutamol abuse detection by athletes is based on a urinary upper threshold defined by the World Anti-Doping Agency (WADA). However, this threshold was determined in healthy, untrained individuals and after a dose of salbutamol inhaled that might not really mirror the condition of asthmatic athletes and the experts's guidelines for asthma management. We aimed to revise this threshold in accordance with recommended clinical practice (that appear to be different from the actual WADA recommendation) and in exercise conditions.

METHODS

For the present open-label design study, we included 12 trained male cyclists (20 to 40 y/o) with asthma. Differently from the previous pharmacokinetic study supporting the actual salbutamol urinary upper threshold, we decided to administer a close to recommended clinical practice daily dose of 3x200 μg.d(-1) inhaled salbutamol (instead of 1600 μg.d(-1) as authorized by the anti-doping policy). Urine salbutamol concentration was quantified by liquid chromatography-tandem ion trap mass spectrometry and corrected for urine density, at rest and after a 90-min cycling effort at 70-80 % of the maximal aerobic power.

RESULTS

The maximum urine salbutamol concentration value peaked after the cycling effort and was 510 ng.mL(-1). That is twice lower than the actual WADA threshold to sanction salbutamol abuse, this "legal" threshold being based on pharmacokinetic data after a daily dose that is 8 fold the total dose sequentially administrated in our study. Considering its 95 % confidence interval, this threshold value could be more stringent.

CONCLUSION

By using conditions in accordance with the experts' clinical and safety guidelines for asthma management in athletes undergoing an intense exercise bout, our study suggests that the urine salbutamol concentration threshold could be lowered to redefine the rule supporting the decision to sanction an athlete for salbutamol abuse.

[Inhaled therapy in asthma]

Because of its advantages, inhaled administration of aerosolized drugs is the administration route of choice for the treatment of asthma and COPD. Numerous technological advances in the devices used in inhaled therapy in recent decades have boosted the appearance of multiple inhalers and aerosolized drugs. However, this variety also requires that the prescribing physician is aware of their characteristics. The main objective of the present review is to summarize the current state of knowledge on inhalers and inhaled drugs commonly used in the treatment of asthma. The review ranges from theoretical aspects (fundamentals and available devices and drugs) to practical and relevant aspects for asthma care in the clinical setting (therapeutic strategies, education, and adherence to inhalers).

Japanese Guideline for Adult Asthma 2014

Adult bronchial asthma (hereinafter, asthma) is characterized by chronic airway inflammation, reversible airway narrowing, and airway hyperresponsiveness. Long-standing asthma induces airway remodeling to cause intractable asthma. The number of patients with asthma has increased, and that of patients who die from asthma has decreased (1.5 per 100,000 patients in 2012). The aim of asthma treatment is to enable patients with asthma to lead a normal life without any symptoms. A good relationship between physicians and patients is indispensable for appropriate treatment. Long-term management with antiasthmatic agents and elimination of the causes and risk factors of asthma are fundamental to its treatment. Four steps in pharmacotherapy differentiate between mild and intensive treatments; each step includes an appropriate daily dose of an inhaled corticosteroid, varying from low to high. Long-acting 02-agonists, leukotriene receptor antagonists, and sustained-release theophylline are recommended as concomitant drugs, while anti-immunoglobulin E antibody therapy has been recently developed for the most severe and persistent asthma involving allergic reactions. Inhaled 02-agonists, aminophylline, corticosteroids, adrenaline, oxygen therapy, and others are used as needed in acute exacerbations by choosing treatment steps for asthma exacerbations depending on the severity of attacks. Allergic rhinitis, chronic obstructive pulmonary disease, aspirin-induced asthma, pregnancy, asthma in athletes, and coughvariant asthma are also important issues that need to be considered.

Cysteinyl leukotriene receptor-1 antagonists as modulators of innate immune cell function

Cysteinyl leukotrienes (cysLTs) are produced predominantly by cells of the innate immune system, especially basophils, eosinophils, mast cells, and monocytes/macrophages. Notwithstanding potent bronchoconstrictor activity, cysLTs are also proinflammatory consequent to their autocrine and paracrine interactions with G-protein-coupled receptors expressed not only on the aforementioned cell types, but also on Th2 lymphocytes, as well as structural cells, and to a lesser extent neutrophils and CD8⁺ cells. Recognition of the involvement of cysLTs in the immunopathogenesis of various types of acute and chronic inflammatory disorders, especially bronchial asthma, prompted the development of selective cysLT receptor-1 (cysLTR1) antagonists, specifically montelukast, pranlukast, and zafirlukast. More recently these agents have also been reported to possess secondary anti-inflammatory activities, distinct from cysLTR1 antagonism, which appear to be particularly effective in targeting neutrophils and monocytes/macrophages. Underlying mechanisms include interference with cyclic nucleotide phosphodiesterases, 5′-lipoxygenase, and the proinflammatory transcription factor, nuclear factor kappa B. These and other secondary anti-inflammatory mechanisms of the commonly used cysLTR1 antagonists are the major focus of the current review, which also includes a comparison of the anti-inflammatory effects of montelukast, pranlukast, and zafirlukast on human neutrophils in vitro, as well as an overview of both the current clinical applications of these agents and potential future applications based on preclinical and early clinical studies.

Exercise-induced bronchospasm: a case study in a nonasthmatic patient

Purpose

To provide an overview of the clinical presentation, diagnosis, and management of exercise-induced bronchospasm (EIB) without underlying asthma.

Data sources

Case presentation and review of the EIB Landmark Survey.

Conclusions

EIB is a common and well-described occurrence in patients with asthma, as well as in patients with no overt respiratory condition. Treatment with a short-acting beta-agonist before starting exercise is effective, yet this treatment approach is underutilized in the majority of patients with asthma.

Implications for practice

This case highlights the implications of undermanaged EIB and the disconnect between healthcare provider recommendations and the beliefs and behaviors in patients with EIB. Inhaled short-acting beta-agonists can attenuate EIB in 80%–95% of patients and are effective during 2–3 h of exercise. Patients with a compromised level of physical activity because of EIB who do not respond to conventional treatment strategies should be referred to a respiratory specialist for diagnostic evaluation and confirmation of underlying asthma. Nurse practitioners should remain vigilant to identify untreated EIB and ensure that affected patients understand the condition and appropriate treatment options.

Cromoglycate, reproterol, or both--what's best for exercise-induced asthma?

OBJECTIVE

International guidelines recommend short- (SABA) or long-acting b-agonists for the prevention of bronchoconstriction after exercise (EIB) in patients with exercise-induced asthma (EIA). However, other drugs are still in discussion for the prevention of EIB. We investigated the efficacy of a combination of inhaled sodium cromoglycate and the β-mimetic drug reproterol versus inhaled reproterol alone and both versus inhaled placebo in subjects with exercise-induced asthma (EIA).

METHODS

The study aimed to prove the preventive effect of a combination of 1-mg reproterol and 2-mg disodium cromoglycate (DSCG) and its single components vs. placebo, measuring the decrease of FEV1 after a standardized treadmill test in 11 patients with recorded EIA. The study medication was twice as high as those of drugs which are commercially available (e.g., Allergospasmin®, Aarane®).

RESULTS

The results revealed that the combination of reproterol and DSCG was significantly effective against a decrease of FEV1 after a standardized exercise challenge test (ECT) compared to placebo. The short-acting b-agonist reproterol alone had almost the same effectiveness as the combination of reproterol and DNCG. The difference between the combination with DNCG and reproterol alone was less than 10% and insignificant (p 0.48). DNCG alone did not show a difference in the effectiveness compared to placebo.

CONCLUSION

Prevention of EIA with the combination of reproterol and DSCG or with reproterol only is effective. An exclusive recommendation in favor of the combination cannot be given due to the low difference in the effectiveness versus reproterol alone. Due to the limited number of subjects and some probands showing protection under DSCG, it cannot be completely excluded that there is some preventive power of DSCG in individual cases.

Avaliação do broncoespasmo induzido pelo exercício avaliado pelo Peak Flow Meter em adolescentes obesos

INTRODUÇÃO: Crianças e adolescentes com excesso de peso apresentam maior prevalência de broncoespasmo induzido pelo exercício (BIE), quando comparados a eutróficos. A espirometria e o peak flow meter são importantes métodos avaliativos da função pulmonar. Porém, a aplicabilidade do medidor do pico de fluxo expiratório (peak flow meter) na detecção do BIE em crianças e adolescentes com excesso de peso não é conhecida, o que justifica o desenvolvimento desta pesquisa. OBJETIVOS: Avaliar e comparar o desencadeamento de broncoespasmo induzido pelo exercício (BIE) em crianças e adolescentes não asmáticos com excesso de peso, avaliados pela espirometria e pelo peak flow meter (PFE). CASUÍSTICA E MÉTODOS: Participaram do estudo 39 voluntários acima do percentil 85º (OB) e 30 eutróficos (EU), de oito a 15 anos. A avaliação da função pulmonar pré e pós-teste de broncoprovocação foi realizada pela espirometria e peak flow meter, de acordo com o protocolo de Del Río-Navarro et al., (2000). O BIE foi considerado positivo quando o voluntário apresentou uma redução > 10% do VEF1 basal ou redução > 20% do PFE PFM e/ou PFE E. RESULTADOS: Na detecção do BIE, a prevalência do grupo obeso foi de 26% avaliado pelo peak flow meter (PFEPFM) e 23% pelo VEF1. O tempo do BIE ocorreu nos primeiros 15 minutos pós-exercício em ambos os parâmetros: (PFE PFM) e VEF1. CONCLUSÃO: Os voluntários obesos apresentaram tempo e prevalências similares de BIE, quando avaliados por ambos os métodos de avaliação pulmonar. O fácil manejo e o baixo custo facilitam a maior acessibilidade para a população geral do peak flow meter, o que demonstra sua importância como parte integrante de um programa educacional no diagnóstico inicial do BIE em vias aéreas de grande calibre.

Sports and performing arts medicine: 4. Events coverage

OBJECTIVE

This self-directed learning module highlights medical coverage of sports events and artistic performances. It is part of the study guide on sports and performing arts medicine in the Self-Directed Physiatric Education Program for practitioners and trainees in physical medicine and rehabilitation. Using a case vignette format, this article specifically focuses on performance anxiety, exercise-associated collapse, exercise-induced asthma, transient quadriparesis, stingers/burners and anterior glenohumeral joint dislocations. The goal of this article is to improve the learner's ability to formulate and implement an appropriate evaluation and treatment algorithm for certain conditions associated with sports and performing arts events.

Association of the variants in AGT gene with modified drug response in Korean aspirin-intolerant asthma patients

The angiotensinogen (AGT) gene enhances the effect of several bronchoconstrictors and produces a peptide that is accumulated in the airways of asthma patients; events that may underpin the pathogenesis of aspirin-intolerant asthma (AIA). To carry out a case-control analysis between AGT and aspirin-induced bronchospasm following treatment with an anti-asthma drug, montelukast (MLK), 38 single nucleotide polymorphisms (SNPs) in AGT were genotyped in 56 AIA cohort. Genotyping was performed with TaqMan assay and haplotypes were inferred using PHASE algorithm ver. 2.0. Statistical analyses of each SNPs and haplotypes were performed using SAS version 9.1. Among 13 variants displaying significant signals, two SNPs (+2401C>G and +2476C>T) in the intronic region of AGT were significantly associated with modification of drug response even after correction for multiple testing (P=0.0009-0.002; P(corr)=0.02-0.03). Furthermore, the two variants also exhibited associations with MLK response rate (P=0.0003-0.0006; P(corr)=0.006-0.01). Although our results are preliminary and further replication in a larger-scale group of subjects should be warranted, these observations provide evidence that AGT variants might be one of genetic factors involved in the response of anti-asthma drugs in AIA patients.

Asthma: Pathophysiology and Diagnosis

Although asthma is a common disorder affecting approximately 7.8% of the United States population (Schiller et al. 2006) or 23 million Americans, the pathogenesis of this disease remains to be fully elucidated. Extensive research over the last few decades has yielded a better understanding of asthma. We know that the basic features of asthma include episodic airways inflammation, airways hyperresponsiveness, and mucous hypersecretion. Although we understand the basic clinical features of asthma, the links between symptoms, physical signs, and underlying pathophysiological mechanisms are still being delineated. Asthma is a heterogeneous disease process with varying phenotypes and presentations. In this chapter, we will briefly explore some major theories of asthma pathogenesis, both new and old. We will also explore how understanding the pathophysiology of asthma can help us to understand the symptoms and presentation of asthma, as well as the best strategies for diagnosing this disease.

Comparison of mannitol and methacholine to predict exercise-induced bronchoconstriction and a clinical diagnosis of asthma

BACKGROUND

Asthma can be difficult to diagnose, but bronchial provocation with methacholine, exercise or mannitol is helpful when used to identify bronchial hyperresponsiveness (BHR), a key feature of the disease. The utility of these tests in subjects with signs and symptoms of asthma but without a clear diagnosis has not been investigated. We investigated the sensitivity and specificity of mannitol to identify exercise-induced bronchoconstriction (EIB) as a manifestation of BHR; compared this with methacholine; and compared the sensitivity and specificity of mannitol and methacholine for a clinician diagnosis of asthma.

METHODS

509 people (6-50 yr) were enrolled, 78% were atopic, median FEV1 92.5% predicted, and a low NAEPPII asthma score of 1.2. Subjects with symptoms of seasonal allergy were excluded. BHR to exercise was defined as a > or = 10% fall in FEV1 on at least one of two tests, to methacholine a PC20 < or = 16 mg/ml and to mannitol a 15% fall in FEV1 at < or = 635 mg or a 10% fall between doses. The clinician diagnosis of asthma was made on examination, history, skin tests, questionnaire and response to exercise but they were blind to the mannitol and methacholine results.

RESULTS

Mannitol and methacholine were therapeutically equivalent to identify EIB, a clinician diagnosis of asthma, and prevalence of BHR. The sensitivity/specificity of mannitol to identify EIB was 59%/65% and for methacholine it was 56%/69%. The BHR was mild. Mean EIB % fall in FEV1 in subjects positive to exercise was 19%, (SD 9.2), mannitol PD15 158 (CI:129,193) mg, and methacholine PC20 2.1(CI:1.7, 2.6) mg/ml. The prevalence of BHR was the same: for exercise (43.5%), mannitol (44.8%), and methacholine (41.6%) with a test agreement between 62 & 69%. The sensitivity and specificity for a clinician diagnosis of asthma was 56%/73% for mannitol and 51%/75% for methacholine. The sensitivity increased to 73% and 72% for mannitol and methacholine when two exercise tests were positive.

CONCLUSION

In this group with normal FEV1, mild symptoms, and mild BHR, the sensitivity and specificity for both mannitol and methacholine to identify EIB and a clinician diagnosis of asthma were equivalent, but lower than previously documented in well-defined populations.

TRIAL REGISTRATION

This was a multi-center trial comprising 25 sites across the United States of America.

Pediatric athletic asthmatics

The main goals of this review are to help the reader to recognize the common symptoms and signs of exercise-induced asthma and the common objective tests used to confirm or rule out the diagnosis and to understand that different forms and intensities of exercise have different asthmagenicity. The review also aims to help the reader to recognize some of the theories of exercise-induced asthma's pathogenesis, to recognize management strategies (including medications), and to be able to identify medications placed on the 2008 prohibited list by the World Anti-Doping Agency and their therapeutic exemptions. It is also important to understand that respiratory symptoms associated with exercise are not necessarily asthma and that through safe participation in physical exercise, athletic asthmatics can excel in competitive sports.

Exercise-induced bronchospasm in children

This review will encompass definition, history, epidemiology, pathogenesis, diagnosis, and management of exercise -induced bronchospasm in the pediatric individual with and without known asthma. Exercise induced asthma is the conventional term for transient airway narrowing in a known asthma in association with strenuous exercise usually lasting 5-10 minutes with a decline in pulmonary function by at least 10%. Exercise induced asthma will be referred to as exercise induced bronchospasm in an asthmatic. Exercise-induced bronchospasm (EIB ) is the same phenomenon in an individual without known asthma. EIB can be seen in healthy individuals including children as well as defense recruits and competitive or elite athletes. The diagnosis with objective exercise challenge methods in conjunction with history is delineated. Management is characterized with pharmacotherapy and non pharmacotherapeutic measures for underlying asthma as well as exercise induced bronchospasm and inhalant allergy. Children can successfully participate in all sports if asthma is properly managed.

Evidence for prescribing exercise as therapy in chronic disease

Considerable knowledge has accumulated in recent decades concerning the significance of physical activity in the treatment of a number of diseases, including diseases that do not primarily manifest as disorders of the locomotive apparatus. In this review we present the evidence for prescribing exercise therapy in the treatment of metabolic syndrome-related disorders (insulin resistance, type 2 diabetes, dyslipidemia, hypertension, obesity), heart and pulmonary diseases (chronic obstructive pulmonary disease, coronary heart disease, chronic heart failure, intermittent claudication), muscle, bone and joint diseases (osteoarthritis, rheumatoid arthritis, osteoporosis, fibromyalgia, chronic fatigue syndrome) and cancer, depression, asthma and type 1 diabetes. For each disease, we review the effect of exercise therapy on disease pathogenesis, on symptoms specific to the diagnosis, on physical fitness or strength and on quality of life. The possible mechanisms of action are briefly examined and the principles for prescribing exercise therapy are discussed, focusing on the type and amount of exercise and possible contraindications.

Asthma and athletes: therapy to compete

Asthma presents special challenges to both the athletes who have it and to their health care providers. This article briefly reviews the problem of asthma--especially exercise-induced asthma--in the competitive athlete, and then describes treatments that are effective in controlling asthma. Drug-doping regulations are explained, as is the worldwide impact of drug doping on competitive athletes who have asthma. This review concludes with recommendations for competitive athletes and their health care providers regarding how to deal with asthma in this patient population.

Inhaled hyaluronic acid against exercise-induced bronchoconstriction in asthma

Hyaluronic acid (HA) is a polysaccharide that is present in human tissues and body fluids. HA has various functions, including a barrier effect, water homeostasis, stabilizing the extracellular matrix, increased mucociliary clearance and elastin injury prevention. It may therefore exert prophylactic activity in the treatment of asthma. We tested the hypothesis that HA inhalation will prevent exercise-induced bronchoconstriction (EIB) in a randomised double-blinded placebo-controlled crossover study. Sixteen asthmatic patients with EIB were included in the study (mean (SD)) (age 24.5 (7.3) yr, FEV1 88.6 (11.3) %predicted, PC20 methacholine (g-mean (SD in DD)) 0.4 (1.5) mg/ml). On two separate visits an exercise challenge was performed 15 min post-inhalation of either HA (3 ml 0.1% in PBS) or placebo (3 ml PBS). The maximum fall in FEV1 and the AUC 30 min post-exercise were used as outcomes. After inhalation of both HA and placebo, baseline FEV1 decreased significantly (HA 4.1 (3.1)%, placebo 2.9 (4.1)%, P<0.017). The maximum fall in FEV1 following exercise challenge was not significantly different between HA versus placebo (median HA 22.50%, placebo 27.20%, P=0.379), as was the AUC (median HA 379.3 min*%fall, placebo 498.9 min*%fall, P=0.501). We conclude that at the current dose, inhaled HA does not significantly protect against EIB. This suggests that HA is not effective as a prophylaxis for EIB in patients with asthma.

Role of leukotriene receptor antagonists in the treatment of exercise-induced bronchoconstriction: a review

Asthma is a very common disorder that still causes significant morbidity and mortality. A high percentage of individuals with asthma also experience exercise-induced bronchoconstriction (EIB). This article reviews the current literature and updates the reader on the safety, efficacy, and clinical applications of leukotriene modifiers in the treatment of EIB.