Montelukast versus salmeterol in patients with asthma and exercise-induced bronchoconstriction. Montelukast/Salmeterol Exercise Study Group

Defining the contractile prostanoid component in hyperosmolar-induced bronchoconstriction in human small airways

Exercise-induced bronchoconstriction (EIB) is thought to be triggered by increased osmolarity at the airway epithelium. The aim of this study was to define the contractile prostanoid component of EIB, using an ex vivo model where intact segments of bronchi (inner diameter 0.5-2 mm) isolated from human lung tissue and subjected to mannitol. Exposure of bronchial segments to hyperosmolar mannitol evoked a contraction (64.3 ± 3.5 %) which could be prevented either by elimination of mast cells (15.8 ± 4.3 %) or a combination of cysteinyl leukotriene (cysLT1), histamine (H1) and thromboxane (TP) receptor antagonists (11.2 ± 2.3 %). Likewise, when antagonism of TP receptor was exchanged for inhibition of either cyclooxygenase-1 (8 ± 2.5 %), hematopoietic prostaglandin (PG)D synthase (20.7 ± 5.6 %), TXA synthase (14.8 ± 4.9 %), or the combination of the latter two (12.2 ± 4.6 %), the mannitol-induced contraction was prevented, suggesting that the TP-mediated component is induced by PGD2 and TXA2 generated by COX-1 and their respective synthases.

Management of Exercise-Induced Bronchoconstriction in Athletes

Exercise-induced bronchoconstriction (EIB) is a phenomenon observed in asthma but is also seen in healthy individuals and frequently in athletes. High prevalence rates are observed in athletes engaged in endurance sports, winter sports, and swimming. The pathophysiology of EIB is thought to be related to hyperventilation, cold air, and epithelial damage caused by chlorine and fine particles in inspired air. Several diagnostic procedures can be used; however, the diagnosis of EIB based on self-reported symptoms is not reliable and requires an objective examination. The hyperosmolar inhalation test and eucapnic voluntary hyperpnea test, which involve indirect stimulation of the airway, are useful for the diagnosis of EIB. A short-acting β-agonist is the first choice for prevention of EIB, and an inhaled corticosteroid is essential for patients with asthma. Furthermore, treatment should accommodate antidoping requirements in elite athletes. Tailoring of the therapeutic strategy to the individual case and the prognosis after cessation of athletic activity are issues that should be clarified in the future.

Cysteinyl Leukotriene Synthesis via Phospholipase A2 Group IV Mediates Exercise-induced Bronchoconstriction and Airway Remodeling

It is well known that the prevalence of asthma is higher in athletes, including Olympic athletes, than in the general population. In this study, we analyzed the mechanism of exercise-induced bronchoconstriction by using animal models of athlete asthma. Mice were made to exercise on a treadmill for a total duration of 1 week, 3 weeks, or 5 weeks. We analyzed airway responsiveness, BAL fluid, lung homogenates, and tissue histology for each period. In mice that were treated (i.e., the treatment model), treatments were administered from the fourth to the fifth week. We also collected induced sputum from human athletes with asthma and analyzed the supernatants. Airway responsiveness to methacholine was enhanced with repeated exercise stimulation, although the cell composition in BAL fluid did not change. Exercise induced hypertrophy of airway smooth muscle and subepithelial collagen deposition. Cysteinyl-leukotriene (Cys-LT) levels were significantly increased with exercise duration. Montelukast treatment significantly reduced airway hyperresponsiveness (AHR) and airway remodeling. Expression of PLA₂G4 (phospholipase A₂ group IV) and leukotriene C₄ synthase in the airway epithelium was upregulated in the exercise model, and inhibition of PLA₂ ameliorated AHR and airway remodeling, with associated lower levels of Cys-LTs. The levels of Cys-LTs in sputum from athletes did not differ between those with and without sputum eosinophilia. These data suggest that AHR and airway remodeling were caused by repeated and strenuous exercise. Cys-LTs from the airway epithelium, but not inflammatory cells, may play an important role in this mouse model.

The burden of exacerbations in mild asthma: a systematic review

Background

Although most patients with asthma have mild disease, data on how mild asthma is defined, and how frequently exacerbations occur in this patient population are scarce, so we aimed to redress this.

Methods

We searched Medline and Medline In-Process (PubMed), and Embase in OVID for English-language publications containing “mild asthma” plus at least one relevant therapy and outcome/keyword, limited to randomised controlled trials (RCTs) and observational studies published between January 1990 and February 2019. Publications were filtered to ensure appropriate data extraction. The main outcomes were the definitions of mild asthma and exacerbations, baseline exacerbation rates and exacerbation data for placebo recipients in prospective studies. Meta-analysis of exacerbation rates was planned.

Findings

Of 4064 articles identified, 64 were included in our review (49 743 subjects); 54 RCTs and 10 observational/other studies. Six main types of definitions of mild asthma were identified. While care was taken to ensure inclusion only of patients with mild asthma, marked heterogeneity was revealed in the definitions of mild asthma and hence the study populations. Reporting of exacerbations also varied widely between studies, precluding meta-analysis. Between 0–22% of patients were hospitalised for asthma or had a severe exacerbation in the previous year, according to baseline data from prospective studies. In RCTs, severe exacerbation rates in placebo recipients taking only short-acting β₂-agonist therapy ranged from 0.20–2.88 per year.

Conclusions

These data provide new evidence of the burden of exacerbations in mild asthma and highlight the need for standardised definitions of mild asthma and of exacerbations to progress further research.

This comprehensive literature review highlights the risk of exacerbations for patients with mild asthmahttps://bit.ly/3cauSb3

Asthma and exercise-induced respiratory disorders in athletes. The position paper of the Polish Society of Allergology and Polish Society of Sports Medicine

Exercise-induced respiratory symptoms describe acute airway narrowing that occurs as a result of exercise. It includes exercise-induced bronchoconstriction (EIB) and exercise-induced asthma (EIA) issues. To provide clinicians with practical guidelines, a multidisciplinary panel of stakeholders was convened to review the pathogenesis of EIB/EIA and to develop evidence-based guidelines for the diagnosis and treatment. Recommendations for the diagnosis and treatment of EIB were developed. High-intensity exercise in polluted environment (cold air, humidity, contamination, allergens) may increase the risk of EIB and asthma symptoms in athletes. Diagnostic procedures should include history taking, physical examination, atopy assessment and functional tests of the respiratory system. A strong recommendation was made for regular use of inhaled glucocorticosteroids and avoidance of short-acting β₂-agonists as the only treatment. The treatment of asthma in athletes should always take into account current anti-doping regulations. This position paper reflects the currently available evidence.

Pharmacologic Strategies for Exercise-Induced Bronchospasm with a Focus on Athletes

Exercise-induced bronchoconstriction (EIB) is the transient narrowing of the airways during and after exercise that occurs in response to increased ventilation in susceptible individuals. It occurs across the age spectrum in patients with underlying asthma and can occur in athletes without baseline asthma. The inflammatory mechanisms underlying EIB in patients without asthma may be distinct from those underlying EIB in patients with asthma. This review summarizes mechanistic and clinical data that can guide the choice of chronic and acute pharmacologic therapies targeting control of EIB. Relevant regulations from the World Anti-Doping Agency are also discussed.

ERS technical standard on bronchial challenge testing: pathophysiology and methodology of indirect airway challenge testing

Recently, this international task force reported the general considerations for bronchial challenge testing and the performance of the methacholine challenge test, a "direct" airway challenge test. Here, the task force provides an updated description of the pathophysiology and the methods to conduct indirect challenge tests. Because indirect challenge tests trigger airway narrowing through the activation of endogenous pathways that are involved in asthma, indirect challenge tests tend to be specific for asthma and reveal much about the biology of asthma, but may be less sensitive than direct tests for the detection of airway hyperresponsiveness. We provide recommendations for the conduct and interpretation of hyperpnoea challenge tests such as dry air exercise challenge and eucapnic voluntary hyperpnoea that provide a single strong stimulus for airway narrowing. This technical standard expands the recommendations to additional indirect tests such as hypertonic saline, mannitol and adenosine challenge that are incremental tests, but still retain characteristics of other indirect challenges. Assessment of airway hyperresponsiveness, with direct and indirect tests, are valuable tools to understand and to monitor airway function and to characterise the underlying asthma phenotype to guide therapy. The tests should be interpreted within the context of the clinical features of asthma.

Addressing unmet needs in understanding asthma mechanisms: From the European Asthma Research and Innovation Partnership (EARIP) Work Package (WP)2 collaborators

Asthma is a heterogeneous, complex disease with clinical phenotypes that incorporate persistent symptoms and acute exacerbations. It affects many millions of Europeans throughout their education and working lives and puts a heavy cost on European productivity. There is a wide spectrum of disease severity and control. Therapeutic advances have been slow despite greater understanding of basic mechanisms and the lack of satisfactory preventative and disease modifying management for asthma constitutes a significant unmet clinical need. Preventing, treating and ultimately curing asthma requires co-ordinated research and innovation across Europe. The European Asthma Research and Innovation Partnership (EARIP) is an FP7-funded programme which has taken a co-ordinated and integrated approach to analysing the future of asthma research and development. This report aims to identify the mechanistic areas in which investment is required to bring about significant improvements in asthma outcomes.

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.

Can a single dose response predict the effect of montelukast on exercise-induced bronchoconstriction?

RATIONALE

Exercise-induced bronchoconstriction (EIB) can be prevented by a single dose of montelukast (MLK). The effect is variable, similar to the variable responsiveness observed after daily treatment with MLK. We hypothesized that the effect of a single MLK-dose (5 or 10 mg) on EIB could predict the clinical effectiveness of longer term once daily treatment.

METHODS

This was a prospective, open-label study. Twenty-four asthmatic adolescents (12-17 years) suboptimally controlled by low-dose inhaled corticosteroids, with ≥10% post-exercise fall in FEV1 , were included. They performed an exercise test at baseline, 20 hr after a single MLK-dose and 40-44 hr after the last dose of 4 weeks once daily treatment. The correlations between the effect of a single dose and 4 weeks treatment on area under the curve (AUC) and maximum % fall in FEV1 were calculated.

RESULTS

AUC0-20 min decreased significantly after a single MLK-dose (P = 0.001, CI: 64.9-218.2), but not after 4 weeks of treatment (P = 0.080, CI: -12.2 to 200.4). There was a moderate correlation between the effect of a single MLK-dose and 4 weeks treatment on AUC0-20 min , r = 0.49 (P = 0.011), and maximum % fall in FEV1 , r = 0.40 (P = 0.035).

CONCLUSION

The protection provided by a single MLK-dose against EIB only modestly predicts the effect of regular treatment against EIB in adolescent asthmatics on low-dose inhaled corticosteroids. If used on a daily base, MLK offered clinically significant protection against EIB in two thirds of adolescents suboptimally controlled by low-dose ICS.

IL-13 desensitizes β2-adrenergic receptors in human airway epithelial cells through a 15-lipoxygenase/G protein receptor kinase 2 mechanism

BACKGROUND

β2-Adrenergic receptor (β2AR) agonists are critical treatments for asthma. However, receptor desensitization can lead to loss of therapeutic effects. Although desensitization to repeated use of β2-agonists is well studied, type 2 inflammation could also affect β2AR function.

OBJECTIVE

We sought to evaluate the effect of the type 2 cytokine IL-13 on β2AR desensitization in human airway epithelial cells (HAECs) and determine whether 15-lipoxygenase-1 (15LO1) binding with phosphatidylethanolamine-binding protein 1 (PEBP1) contributes to desensitization through release of G protein receptor kinase 2 (GRK2).

METHODS

HAECs in air-liquid interface culture with or without IL-13 (48 hours) or isoproterenol hydrochloride (ISO; 30 minutes) pretreatment were stimulated with ISO (10 minutes). Cyclic adenosine 3, 5-monophosphate (cAMP) levels were measured using ELISA, and β2AR and GRK2 phosphorylation was measured using Western blotting. Short interfering RNA was used for 15LO1 knockdown. Interactions of GRK2, PEBP1, and 15LO1 were detected by means of immunoprecipitation/Western blotting and immunofluorescence. HAECs and airway tissue from control subjects and asthmatic patients were evaluated for I5LO1, PEBP1, and GRK2.

RESULTS

Pretreatment with ISO or IL-13 decreased ISO-induced cAMP generation compared with ISO for 10 minutes alone paralleled by increases in β2AR and GRK2 phosphorylation. GRK2 associated with PEBP1 after 10 minutes of ISO in association with low phosphorylated GRK2 (pGRK2) levels. In contrast, in the presence of IL-13 plus ISO (10 minutes), binding of GRK2 to PEBP1 decreased, whereas 15LO1 binding and pGRK2 levels increased. 15LO1 knockdown restored ISO-induced cAMP generation. These findings were recapitulated in freshly brushed HAECs from cells and tissue of asthmatic patients.

CONCLUSION

IL-13 treatment of HAECs leads to β2AR desensitization, which involves 15LO1/PEBP1 interactions to free GRK2, and allows it to phosphorylate (and desensitize) β2ARs, suggesting that the beneficial effects of β2-agonists could be blunted in patients with type 2 associated asthma.

Evidence-based risk assessment and recommendations for physical activity clearance: respiratory disease

The 2 most common respiratory diseases are chronic obstructive pulmonary disease (COPD) and asthma. Growing evidence supports the benefits of exercise for all patients with these diseases. Due to the etiology of COPD and the pathophysiology of asthma, there may be some additional risks of exercise for these patients, and hence accurate risk assessment and clearance is needed before patients start exercising. The purpose of this review was to evaluate the available literature regarding the risks of exercise for patients with respiratory disease and provide evidence-based recommendations to guide the screening process. A systematic review of 4 databases was performed. The literature was searched to identify adverse events specific to exercise. For COPD, 102 randomized controlled trials that involved an exercise intervention were included (n = 6938). No study directly assessed the risk of exercise, and only 15 commented on exercise-related adverse events. For asthma, 30 studies of mixed methodologies were included (n = 1278). One study directly assessed the risk of exercise, and 15 commented on exercise-related adverse events. No exercise-related fatalities were reported. The majority of adverse events in COPD patients were musculoskeletal or cardiovascular in nature. In asthma patients, exercise-induced bronchoconstriction and (or) asthma symptoms were the primary adverse events. There is no direct evidence regarding the risk of exercise for patients with COPD or asthma. However, based on the available literature, it would appear that with adequate screening and optimal medical therapy, the risk of exercise for these respiratory patients is low.

Beta₂-agonists for exercise-induced asthma

BACKGROUND

It is well known that physical exercise can trigger asthma symptoms and can induce bronchial obstruction in people without clinical asthma. International guidelines on asthma management recommend the use of beta2-agonists at any stage of the disease. At present, however, no consensus has been reached about the efficacy and safety of beta2-agonists in the pretreatment of exercise-induced asthma and exercise-induced bronchoconstriction. For the purpose of the present review, both of these conditions are referred to by the acronymous EIA, independently from the presence of an underlying chronic clinical disease.

OBJECTIVES

To assess the effects of inhaled short- and long-acting beta2-agonists, compared with placebo, in the pretreatment of children and adults with exercise-induced asthma (or exercise-induced bronchoconstriction).

SEARCH METHODS

Trials were identified by electronic searching of the Cochrane Airways Group Specialised Register of Trials and by handsearching of respiratory journals and meetings. Searches are current as of August 2013.

SELECTION CRITERIA

We included randomised, double-blind, placebo-controlled trials of any study design, published in full text, that assessed the effects of inhaled beta2-agonists on EIA in adults and children. We excluded studies that did not clearly state diagnostic criteria for EIA.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures as expected by The Cochrane Collaboration.

MAIN RESULTS

We included 53 trials consisting of 1139 participants. Forty-eight studies used a cross-over design, and five were performed in accordance with a parallel-group design. Forty-five studies addressed the effect of a single beta2-agonist administration, and eight focused on long-term treatment. We addressed these two different intervention regimens as different comparisons.Among primary outcomes for short-term administration, data on maximum fall in forced expiratory volume in 1 second (FEV1) showed a significant protective effect for both short-acting beta-agonists (SABA) and long-acting beta-agonists (LABA) compared with placebo, with a mean difference of -17.67% (95% confidence interval (CI) -19.51% to -15.84%, P = 0.00001, 799 participants from 72 studies). The subgroup analysis of studies performed in adults compared with those performed in children showed high heterogeneity confined to children, despite the comparable mean bronchoprotective effect.Secondary outcomes on other pulmonary function parameters confirmed a more positive and protective effect of beta2-agonists on EIA compared with placebo. Occurrence of side effects was not significantly different between beta2-agonists and placebo.Overall evaluation of the included long-term studies suggests a beta2-agonist bronchoprotective effect for the first dose of treatment. However, long-term use of both SABA and LABA induced the onset of tolerance and decreased the duration of drug effect, even after a short treatment period.

AUTHORS' CONCLUSIONS

Evidence of low to moderate quality shows that beta2-agonists, both SABA and LABA, when administered in a single dose, are effective and safe in preventing EIA.Long-term regular administration of inhaled beta2-agonists induces tolerance and lacks sufficient safety data. This finding appears to be of particular clinical relevance in view of the potential for prolonged regular use of beta2-agonists as monotherapy in the pretreatment of EIA, despite the warnings of drug agencies (FDA, EMA) regarding LABA.

Impact of montelukast on asthma associated with rhinitis, and other triggers and co-morbidities

INTRODUCTION

Rhinitis and other specific triggers or co-morbidities (tobacco exposure, excess weight, aspirin sensitivity or heredity factors) are frequently associated with uncontrolled asthma. Asthma associated with these exacerbating factors appears to be related to an increase in leukotriene-mediated inflammation.

METHODS

We reviewed the role of montelukast, a leukotriene receptor antagonist, in the treatment of asthma associated with these factors by using the PubMed database to search the English and French biomedical literature for articles describing randomized-controlled trials, large observational studies and reviews (published up to May 2012, inclusive).

RESULTS

Montelukast, either alone or in combination with other drugs, is an effective treatment against rhinitis-associated asthma. Montelukast also offers therapeutic benefits against exercise-induced asthma or in cases of asthma linked to tobacco exposure, excess weight or aspirin hypersensitivity. Thus, for some patients, montelukast may constitute an alternative to the gold-standard treatment of inhaled corticosteroids. Polymorphisms in several genes encoding proteins of the leukotriene signaling pathway may contribute to the variability in response to montelukast.

CONCLUSIONS

In conclusion, we have shown that montelukast treatment could be of particular benefit to subgroups of patients with asthma associated with rhinitis, exercise, tobacco exposure, being overweight or aspirin hypersensitivity.

Montelukast in asthma: a review of its efficacy and place in therapy

Many studies have been published in the last 10 years on the efficacy and safety of montelukast in asthma since this drug entered the market. Experimental studies, in vitro and in vivo, and clinical studies on large numbers of patients with asthma of different severity have clearly demonstrated that montelukast is able to modify the pathophysiological mechanisms of the disease, and to improve to some extent the clinical and functional manifestations of asthma. Studies of montelukast as monotherapy or in combination with other drugs, mainly inhaled corticosteroids (ICS), versus different comparator drugs have contributed to the positioning of montelukast in the different levels of asthma treatment, according to the Global Initiative for Asthma Guidelines. Montelukast may be used as monotherapy as an alternative to low-dose ICS (particularly in a step-down strategy) or in addition to ICS for improving clinical manifestations by an increase in anti-inflammatory effects and a sparing of corticosteroids. The heterogeneity of asthma has received a large amount of attention in the last few years in order to better tailor treatment according to the different clinical and biological phenotypes of asthma. Montelukast has proven to be particularly effective in exercise-induced asthma and in asthma associated with allergic rhinitis. Other phenotypes where montelukast is effective include asthma in obese patients, asthma in smokers, aspirin-induced asthma and viral-induced wheezing episodes. The safety profile of montelukast is very good, and the suspicions of increased risk of Churg-Strauss syndrome or suicide have not been confirmed.

Pharmacotherapy for exercise-induced asthma: allowing normal levels of activity and sport

Exercise-induced bronchoconstriction (EIB) is experienced by the majority of an estimated 300 million individuals who have asthma, a condition that affects all ages and is increasing globally. Respiratory water loss with dehydration of the airways causing mediator release and airway narrowing is considered the cause of EIB, the severity of which will be increased if the inhaled air is cold or polluted. Adequate control of asthma is essential to minimize or prevent EIB and permit normal levels of physical activity and sport. This is important because exercise is a necessary component of daily living, assists in obtaining and maintaining a healthy body and has been demonstrated to benefit asthmatics. Inhaled glucocorticosteroids and inhaled β(2)-adrenoceptor agonists (IβA) are the pharmacological agents of choice to manage asthma and minimize EIB, assisted when necessary, by other drugs including leukotriene receptor antagonists and chromones. Tolerance from daily use of IβA is of concern and more flexible drug therapy needs to be considered. Optimal use of inhalers to deliver drugs effectively requires closer attention. Pharmacogenetics may hold the key to future drug therapy.

Role of leukotriene receptor antagonists in the management of pediatric asthma: an update

At present, the main indications for leukotriene receptor antagonists (LTRA) in pediatric asthma are as add-on therapy to inhaled corticosteroids (ICS) and as initial controller therapy in children with mild asthma, especially those who cannot or will not use ICS. LTRA are also useful for patients who have concomitant rhinitis, and patients with viral-induced wheeze and exercise-induced asthma. It should be noted that the benefits of LTRA therapy have been demonstrated in children as young as 6 months of age and recent clinical trials have further proven the benefits of LTRA in acute asthma exacerbations. However, considering the important pro-inflammatory effects that leukotrienes (LT) have in experimental models of asthma, it may seem surprising that LTRA treatment outcomes are not better and that in some clinical trials only a minority of patients could be classified as full responders. This could be explained by potential additional LT receptors that are not affected by LTRA. Such receptors could represent new therapeutic targets in asthma. Furthermore, progress in differentiating between asthma phenotypes that result from different pathogenic mechanisms, some of which may involve LT to a lesser degree, should lead to an improved, personalized use of LTRA for treating asthma.

Montelukast versus inhaled corticosteroids in the management of pediatric mild persistent asthma

International guidelines recommend the use of inhaled corticosteroids (ICSs) as the preferred therapy, with leukotriene receptor antagonists (LTRAs) as an alternative, for the management of persistent asthma in children. Montelukast (MLK) is the first LTRA approved by the Food and Drug Administration for the use in young asthmatic children.Therefore, we performed an analysis of studies that compared the efficacy of MLK versus ICSs. We considered eligible for the inclusion randomized, controlled trials on pediatric populations with Jadad score > 3, with at least 4 weeks of treatment with MLK compared with ICS.Although it is important to recognize that ICSs use is currently the recommended first-line treatment for asthmatic children, MLK can have consistent benefits in controlling asthmatic symptoms and may be an alternative in children unable to use ICSs or suffering from poor growth. On the contrary, low pulmonary function and/or high allergic inflammatory markers require the corticosteroid use.

Pharmacotherapy of patients with mild persistent asthma: strategies and unresolved issues

In studies comparing regular versus on-demand treatment for patients with mild persistent asthma, on-demand treatment seems to have a similar efficacy on clinical and functional outcomes, but it does not suppress chronic airway inflammation or airway hyper-responsiveness (AHR) associated with asthma. Data on the efficacy of a continuous treatment with inhaled corticosteroids (ICS) in preventing the progression of asthma are conflicting. There is the possibility that patients without a regular treatment with ICS may develop a more severe asthma associated with airway structural changes (remodeling) and a progressive loss of lung function. However, the possible clinical and functional consequences of persistent, not controlled, airway inflammation in patients with asthma have to be established. Assessment of asthma control should include inflammatory outcomes, such as fraction of exhaled nitric oxide and sputum eosinophil counts. Until the relationships between symptoms, lung function tests, AHR, airway inflammation, exacerbations, and airway remodeling are clarified, regular treatment seems to be generally more appropriate than on-demand treatment to warrant a greater control of asthma. Select subgroups of patients with mild asthma who are well controlled by regular treatment might adopt the on-demand treatment plan as an intermediate step toward the suspension of controller medication. The increasing evidence for heterogeneity of asthma, the growing emphasis on asthma subphenotypes, including molecular phenotypes identified by omics technologies, and their possible implications for different asthma severity and progression and therapeutic response, are changing the paradigm of treating patients with asthma only based on classification of their disease severity to a pharmacological strategy more focused on the individual asthmatic patient. Pharmacological treatment of asthma is going toward a personalized approach.

Leukotriene pathway in sickle cell disease: a potential target for directed therapy

Sickle cell disease (SCD) is characterized by recurrent episodes of vaso-occlusion, resulting in tissue ischemia and end-organ damage. Inflammation is critical to the pathogenesis of vaso-occlusion and has been associated with SCD-related morbidity and mortality. Despite the impact of inflammation, no directed anti-inflammatory therapies for the treatment or prevention of vaso-occlusive events currently exist. Among individuals with SCD, asthma is a comorbid inflammatory condition that increases the risk of pain episodes, acute chest syndrome and death. Inflammation associated with asthma could augment the proinflammatory state of SCD, increasing episodes of vaso-occlusion. Leukotrienes are inflammatory mediators that play a prominent role in the pathogenesis of asthma and have been associated with SCD-related morbidity. Targeting inflammatory mediators, such as leukotrienes, is a promising approach for the development of novel therapies for the treatment of SCD. This review will examine the relationship between inflammation and vaso-occlusion, with particular focus on the leukotriene pathway.

The environment, the airway, and the athlete

OBJECTIVE

To review the interaction of environmental factors with host conditions, including atopy, the potential resulting impaired upper and lower airway function, and diagnostic and therapeutic considerations in the athlete.

DATA SOURCES

OVID, MEDLINE, and PubMed searches were performed cross-referencing the keywords asthma, athlete, atopy, bronchospasm, exercise, pollution, and rhinitis.

STUDY SELECTION

Articles were selected based on relevance to the subject matter.

RESULTS

Recent studies have yielded significant advances in our understanding of how intrinsic and extrinsic factors can potentially result in impaired function of the airways of athletes. Extrinsic factors include environmental exposure to temperature, humidity, aeroallergens, irritants, and pollution. Intrinsic factors include atopy, allergic rhinitis, asthma, and anatomical variants. These intrinsic and extrinsic factors can affect both the athlete's quality of life and athletic performance. However, uncertainty remains regarding relative contributions of these factors in explaining the high degree of bronchospasm seen in various populations of athletes with and without asthma, and no consensus exists regarding the most appropriate diagnostic and therapeutic modalities.

CONCLUSIONS

Great variability exists in the presentation, laboratory findings, diagnostic maneuvers, and response to therapeutic measures among populations of athletes in different sports and among individuals. An improved understanding of the unique exposures faced by athletes in different disciplines, of the available tests for pursuing the appropriate diagnosis, and of the available therapies will allow the allergist to provide clinical improvement and allow the athlete to find relief and achieve his/her full potential.

Leukotriene modifiers for asthma treatment

Leukotrienes (LTs), including cysteinyl LTs (CysLTs) and LTB(4) , are potent lipid mediators that have a role in the pathophysiology of asthma. At least two receptor subtypes for CysLTs, CysLT(1) and CysLT(2) , have been identified. The activation of the CysLT(1) receptor is responsible for most of the pathophysiological effects of CysLTs in asthma, including increased airway smooth muscle activity, microvascular permeability, and airway mucus secretion. LTB(4) might have a role in severe asthma, asthma exacerbations, and the development of airway hyperresponsiveness. CysLT(1) receptor antagonists can be given orally as monotherapy in patients with mild persistent asthma, but these drugs are generally less effective than inhaled glucocorticoids. Combination of CysLT(1) receptor antagonists and inhaled glucocorticoids in patients with more severe asthma may improve asthma control and enable the dose of inhaled glucocorticoids to be reduced while maintaining similar efficacy. The identification of subgroups of asthmatic patients who respond to CysLT(1) receptor antagonists is relevant for asthma management as the response to these drugs is variable. CysLT(1) receptor antagonists have a potential anti-remodelling effect that might be important for preventing or reversing airway structural changes in patients with asthma. This review discusses the role of LTs in asthma and the role of LT modifiers in asthma treatment.

Comparative clinical evaluation of ketotifen and montelukast sodium in asthmatic Iraqi patients

Asthma is a common and chronic inflammatory condition of the airways whose cause is not completely understood. Although many classes of drugs are used for management of asthma, the response is variable due to multifactor reasons. This study was designed to evaluate the outcome of using ketotifen or montelukast sodium in Iraqi asthmatic patients. Single blinded randomized clinical trial was utilized, in which 100 asthmatic patients were recruited from Al-Karama hospital and randomized into two groups; 1st group (50 patients, treated with ketotifen for 4 weeks) and 2nd group (50 patients treated with montelukast sodium for 4 weeks). Asthma symptom score and wheezing were recorded at the beginning (first visit) and at the end of the study (after one month). Pulmonary function tests (PFTs) were performed by spirometry, and the patients' use of asthma drugs and their symptoms were evaluated at each visit. The result showed that asthma symptom, chest wheezing, and PFT values were significantly improved in the two groups at the end of the study compared to first visit (p < 0.05). All symptoms were significantly lower and PFT values were higher in the 2nd group compared to 1st group (p < 0.05). In conclusion, both ketotifen and montelukast sodium showed significant changes in asthma symptoms and PFT after one month of treatment, but the changes were more significant with montelukast group (2nd group) compared with ketotifen group (1st group) and this indicate that montelukast was more effective than ketotifen in treatment of asthmatic patients.

Effect of montelukast or salmeterol added to inhaled fluticasone on exercise-induced bronchoconstriction in children

OBJECTIVES

To evaluate the effect of montelukast, 5 mg, or inhaled salmeterol, 50 microg, added to inhaled fluticasone in reducing the maximum percentage decrease in forced expiratory volume in 1 second (FEV1) after a standardized exercise challenge and response to rescue bronchodilation with albuterol in children aged 6 to 14 years with persistent asthma and exercise-induced bronchoconstriction (EIB).

METHODS

Randomized, double-blind, double-dummy, multicenter, 2-period, 4-week, crossover study conducted between December 22, 2005 and November 14, 2008 at 30 centers in Europe, Asia, Mexico, and South America. Patients with asthma receiving inhaled corticosteroids demonstrated an FEV1 of 70% or higher of the predicted value and EIB (defined as a decrease in FEV1 > or = 15% compared with preexercise baseline FEV1 on 2 occasions before randomization). Standardized exercise challenges were performed at baseline (prerandomization) and at the end of each active treatment period.

RESULTS

Of 154 patients randomized, 145 completed the study. Montelukast, compared with salmeterol, significantly reduced the mean maximum percentage decrease in FEV1 (10.6% vs 13.8%; P = .009), mean area under the curve for the first 20 minutes after exercise (116.0% x min vs 168.8% x min; P = .006), and median time to recovery (6.0 vs 11.1 minutes; P = .04). Response to albuterol rescue after exercise challenge was significantly greater (P < .001) with montelukast. Montelukast and salmeterol were generally well tolerated.

CONCLUSIONS

Attenuation and response of EIB to albuterol rescue after exercise challenge were significantly better with montelukast than with salmeterol after 4 weeks of treatment.

Exercise-induced asthma in children

Exercise-induced bronchoconstriction affects 40-90% of people with asthma, compared with 3-15% of the general population. Exercise-induced asthma (EIA) is diagnosed on the basis of subjective symptoms of airflow obstruction during and after exercise, objective measures of airflow obstruction and the exclusion of alternative diagnoses. Although the pathogenesis of EIA has not been fully elucidated, two major theories have been proposed: the airway rewarming theory and the hyperosmolarity theory. Increasing evidence suggests that airway inflammation plays a major role in the pathogenesis of EIA. In this article, we review the prevalence, pathogenesis, methods for diagnosis and treatment of EIA, as well as the responsiveness of children and adolescents to EIA therapies.

Montelukast in the treatment of asthma and beyond

Asthma is a chronic inflammatory disease affecting over 300 million people worldwide. The common association with allergic rhinitis and the presence of proinflammatory cells and mediators in the circulation of patients qualify asthma as a systemic disease. This characteristic and the fact that the gold-standard therapy for persistent asthma, inhaled corticosteroids, cannot suppress all components of airway inflammation and fail to adequately penetrate into the small airways, warrant the quest for effective systemic anti-asthma therapies. This review describes the most important controlled studies of montelukast, a once-daily leukotriene receptor antagonist, in asthma and allergic rhinitis in both adults and children. Montelukast is a systemically active drug with a targeted, dual mechanism of action, acting both as a bronchodilator and anti-inflammatory. In patients of all ages, montelukast has shown a favorable safety profile and was well-tolerated. Both as monotherapy or in combination with inhaled corticosteroids, montelukast produced clinically relevant improvements in asthma-related parameters, including symptoms, lung function parameters, quality of life and the number of asthma exacerbations. Furthermore, bronchoprotective effects have been reported both against specific and nonspecific bronchoactive stimuli. Similarly, in patients with allergic rhinitis, montelukast produced substantial improvements in symptoms and quality of life. Long-term studies aimed to determine its effects on airway remodeling are still lacking.

Montelukast in the treatment of asthma as a systemic disease

Asthma affects 300 million people worldwide. The common association of asthma with allergic rhinitis and the presence of proinflammatory mediators in the circulation of patients provide strong evidence for the need to treat asthma as a systemic disease. The leukotriene receptor antagonist montelukast is a disease-specific oral medication that has dual effects on airway smooth muscle cells and inflammatory processes. This review describes recent randomized, controlled studies of montelukast in asthma and allergic rhinitis in adults and children as young as 3 months old. Montelukast treatment consistently produced significant reductions in asthma exacerbations. While many patients may benefit from montelukast as monotheray, combination treatment for chronic asthma with inhaled corticosteroids is advocated as being rational. Significant improvements in symptoms and quality of life were observed in allergic rhinitis patients. Montelukast is well tolerated in patients of all ages. Long-term studies are underway to determine its effects on airway remodeling.

Role of Leukotrienes and Leukotriene Modifiers in Asthma

Leukotrienes (LTs), including cysteinyl LTs (CysLTs) and LTB₄, are potent lipid mediators that are pivotal in the pathophysiology of asthma phenotypes. At least two receptor subtypes for CysLTs - CysLT1 and CysLT₂ - have been identified. Most of the pathophysiological effects of CysLTs in asthma, including increased airway smooth muscle activity, microvascular permeability and airway mucus secretion, are mediated by the activation of the CysLT1 receptor. LTB₄ may have a role in the development of airway hyperresponsiveness, severe asthma and asthma exacerbations. Although generally less effective than inhaled glucocorticoids, CysLT₁ receptor antagonists can be given orally as monotherapy in patients with persistent mild asthma. In patients with more severe asthma, CysLT₁ receptor antagonists can be combined with inhaled glucocorticoids. This therapeutic strategy improves asthma control and enables the dose of inhaled glucocorticoids to be reduced, while maintaining similar efficacy. The identification of subgroups of patients with asthma who respond to CysLT₁ receptor antagonists is relevant for asthma management, as the response to these drugs is variable. The potential anti-remodeling effect of CysLT₁ receptor antagonists might be important for preventing or reversing airway structural changes in patients with asthma. This review discusses the role of LTs in asthma and the therapeutic implications of the pharmacological modulation of the LT pathway for asthma.

Use and safety of long-acting β2-agonists for pediatric asthma

Asthma guidelines recommend the use of long-acting β2-agonists (LABAs) as the preferred add-on therapy for adults and children over 5 years of age when asthma is inadequately controlled by inhaled corticosteroids alone. It has been suggested that LABA use may be associated with an increased risk of morbidity and mortality; however, this view is controversial since study findings have been inconsistent. While the safety profile of LABA monotherapy has been questioned, the value of concomitant inhaled corticosteroids to eliminate possible risks remains unproven. There is a paucity of efficacy and safety data for LABA use in children, and existing evidence is not sufficiently convincing to demonstrate a clear position for LABAs in the management of childhood asthma. The main aims of this article are to place LABAs in context in the management of childhood asthma and evaluate the current evidence for safety and efficacy.

Exercise-induced wheeze: Fraction of exhaled nitric oxide-directed management

BACKGROUND AND OBJECTIVE

Exercise-induced wheeze (EIW) is common. Several treatment options exist. Patients with low fraction of exhaled nitric oxide (F(E)NO) are unlikely to be steroid-responsive and might benefit from non-steroidal therapies. We assessed: the efficacy of cromoglycate, formoterol and montelukast in patients with EIW and low F(E)NO (<35 ppb) in a randomized cross-over trial, and the efficacy of inhaled corticosteroid in a high F(E)NO (>35 ppb) group.

METHODS

Patients had EIW and airway hyperresponsiveness (AHR) to mannitol and/or exercise. Those with low F(E)NO (n = 19) received cromoglycate (20 mg inh. bd + before challenge tests), formoterol (12 microg inh. bd + before challenge tests) and montelukast (10 mg p.o. od), each for 2 weeks. Those with high F(E)NO (n = 20) took inhaled fluticasone (500 microg) daily for 4 weeks. Primary end-points were: 50% reduction in maximum FEV(1) %fall (clinical protection) and decrease in AHR to mannitol.

RESULTS

In patients with low F(E)NO, cromoglycate, formoterol and montelukast significantly decreased AHR to mannitol in 63%, 61% and 47% of patients, respectively. In this group, the magnitude of exercise-induced bronchoconstriction (EIB) was significantly reduced with montelukast and formoterol; between-treatment differences were not significant. Of 6/19 with low F(E)NO and EIB, protection occurred in 67% (cromoglycate), 83% (formoterol) and 50% (montelukast), respectively. In the high F(E)NO group, AHR to mannitol and EIB decreased significantly with fluticasone (P < 0.001, P = 0.005, respectively), and protection occurred in 7/8 (88%) with EIB.

CONCLUSIONS

In patients with EIW and low F(E)NO, the number of 'responders' to cromoglycate, formoterol and montelukast was similar. In a high F(E)NO population the response to inhaled corticosteroid was highly significant and comparable to previous studies.

Section 2. Exercise-Induced Bronchospasm: Albuterol versus Montelukast: Highlights of the Asthma Summit 2009: Beyond the Guidelines

Exercise-induced bronchospasm (EIB) involves airway obstruction with an onset shortly after exercising. It can occur in individuals without a diagnosis of asthma, but is most common in asthmatic patients (and in this scenario may be referred to as exercise-induced asthma, EIA), correlating with the patient's degree of airway hyperreactivity. While albuterol is the most commonly used rescue and prophylactic medication for EIB, the leukotriene antagonist, monetlukast, may be an appropriate choice for some patients. Clinical data have shown that once-daily treatment with montelukast (5 or 10 mg tablet) can offer protection against EIB within 3 days for some patients. Such an approach might be preferred for patients who have difficulty with inhaled medications and for children who cannot access their inhalers during the school day. Montelukast also may be an option to reduce side effects associated with albuterol for individuals who exercise regularly.

Effect of ciclesonide on bronchial asthma in athletes

BACKGROUND

Although it is well established that the incidence of bronchial asthma is higher in the athlete population than in the general population, little information exists about the efficacy of treatment of bronchial asthma in the athlete population.

OBJECTIVES

We conducted this study with the objective of determining the efficacy of treatment of bronchial asthma in an athlete population living in Niigata Prefecture, Japan.

METHODS

We conducted a retrospective study of bronchial asthma in an athlete population. Athletes diagnosed as having asthma, based on the Global Initiatives for Asthma (GINA) guidelines, who visited the Niigata Institute for Health and Sports Medicine between January 2007 and June 2008 were enrolled in this study. We compared two groups of patients, a group treated with ciclesonide (CIC) alone and another treated with montelukast alone, with the treatment duration lasting at least 3 months in both groups. The CIC or montelukast groups were compared in terms of the clinical symptoms, pulmonary function parameters, and fraction of exhaled nitric oxide (FENO).

RESULTS

There were no significant differences in the sex distribution, age, frequency of symptoms, pulmonary function parameters, or other examination data before treatment between the CIC and montelukast groups. The CIC group tended to show better symptom control and to need fewer changes of treatment than the montelukast group. While improvements of the pulmonary function parameters and FENO values were observed in the CIC group, no significant changes of these parameters were observed in the montelukast group.

CONCLUSIONS

These data suggest that CIC offers greater promise for the control of asthma than montelukast in the athlete population, although further investigation is required.

Exercise-induced bronchoconstriction in asthmatic children: a comparative systematic review of the available treatment options

The aim of this article is to critically review the efficacy and safety data from randomized controlled trials (RCTs) using inhaled corticosteroids (ICSs), long- or short-acting beta(2)-adrenoceptor agonists (LABAs, SABAs), parasympatholytics and oral leukotriene receptor antagonists in the management of exercise-induced bronchoconstriction (EIB) in children with persistent asthma (EIA). The studies with sufficient information on patient characteristics and outcomes were chosen using a MEDLINE search. Results from the individual searches were combined and repeated. Studies were also found by reviewing the reference lists of the articles not included in this review. Studies focusing solely on individuals with asthma and other allergic co-morbidities (i.e. a degree of bronchial reversibility) were considered in this review. To make the paper evidence-based, the design and the quality of different studies were assessed employing the Sign criteria (evidence level [EL] and grades of recommendation [GR]). No additional statistical analyses were performed. Most of studies included paediatric patients with underlying EIA. We need to distinguish children with recurrent asthma symptoms in whom EIB is also present (patients with EIA) from asthmatic subjects whose symptoms appear only as a result of exercise (patients with EIB). Further controller treatment is indicated in patients with EIA and further reliever treatment in patients with EIB. ICSs are the first-choice controller drugs for EIA in children with persistent asthma (Sign grade of recommendation [GR]:A). In children with EIA without complete control with ICSs, SABAs (GR:A), leukotriene receptor antagonists (LTRAs) [GR:A] or LABAs (GR:A) may be added to gain control. Treatment with relievers such as SABAs (GR:A), parasympatholytics (GR:B) or, eventually, LABAs (GR:A), administered 10-15 minutes before exercise is the most preferable method of preventing EIB symptoms in children; however, not as monotherapy in children with EIA. The disadvantages and controversy relating to inhaled beta(2)-adrenoceptor agonist use lie in the development of tolerance to their effect when they are used on a regular basis, and the possibility of a resulting underuse of ICSs in patients with EIA. Researchers and guidelines recommend that if any patient requires treatment with a beta(2)-adrenoceptor agonist more than twice weekly, a low dose of ICSs should be administered. Inhaled parasympatholytics may be effective as preventive relievers in some children with EIB or EIA, especially among those with increased vagal activity. LTRAs have a well balanced efficacy-safety profile in preventing the occurrence of EIB symptoms in children. Compared with LABAs, LTRAs produce persistent attenuation of EIB and possess an additional effect with rescue SABA therapy in persistent asthmatic patients with EIA. A disadvantage of LTRAs is a non-response phenomenon. There are still insufficient data on the efficacy-safety profiles of ICS/LABA combination drugs in the treatment of EIA in children to recommend this treatment without caution. Safety profiles of inhaled SABAs, anticholinergics and montelukast in approved dosages seem sufficient enough to recommend use of these drugs in the prevention of EIB symptoms in children. Many researchers agree that treatment of EIA in children should always be individualized.

Exercise-induced asthma: critical analysis of the protective role of montelukast

Exercise-induced asthma/exercise-induced bronchospasm (EIA/EIB) is a prevalent and clinically important disease affecting young children through older adulthood. These terms are often used interchangeably and the differences are not clearly defined in the literature. The pathogenesis of EIA/EIB may be different in those with persistent asthma compared to those with exercise-induced symptoms only. The natural history of EIA is unclear and may be different for elite athletes. Leukotriene biology has helped the understanding of EIB. The type and intensity of exercise are important factors for EIB. Exercise participation is necessary for proper development and control of EIA is recommended. Symptoms of EIB should be confirmed by proper testing. Biologic markers may also be helpful in diagnosis. Not all exercise symptoms are from EIB. Many medication and nonpharmacologic treatments are available. Asthma education is an important component of managing EIA. Many medications have been tested and the comparisons are complicated. Montelukast is a US Food and Drug Administration-approved asthma and EIB controller and has a number of potential advantages to other asthma medications including short onset of action, ease of use, and lack of tolerance. Not all patients improve with montelukast and rescue medication should be available.

Leukotriene modifiers in the treatment of asthma in children

Asthma is one of the most common respiratory disorders in clinical practice, affecting up to 13% of people worldwide. Inflammation is the most important component of asthma and inhaled corticosteroids (ICS) are recommended as the first line controller treatment for patients of all ages. Treatment with corticosteroids is often unable to fully control asthma symptoms and progression. Recently, leukotrienes have come to the forefront of research as they have been found play a pivotal role in the airway inflammatory process, and specific drugs have been developed to target them. Cysteiny leukotriene antagonists (LTRAs) have recently emerged as important therapeutic options that show a large potential clinical utility. Three specific LTRAs are licensed for clinical use: montelukast, zafirlukast and pranlukast, although montelukast is the only drug approved in the paediatric age range. It is well tolerated (although adverse effects such as headaches, abdominal pain, rashes, angioedema, pulmonary eosinophilia and arthralgia have been reported) and shows many positive effects in asthmatic patients. Current Global Initiative for Asthma guidelines recommend LTRAs as: (1) a second choice treatment to ICS for patients with mild persistent asthma, (2) an add-on therapy to reduce the dose of ICS in patients with moderate or severe asthma, due to the different and complementary mechanisms of action of these agents. LTRAs may be particularly appropriate choices in a number of clinical situations, including the following: patients with concomitant rhinitis; patients with viral-induced wheeze; patients with exercise-induced bronchoconstriction (EIB) and, in children aged 2-5 years, to reduce the frequency of asthma exacerbations.

Role of leukotrienes in exercise-induced bronchoconstriction

Exercise-induced bronchoconstriction (EIB) refers to acute airflow obstruction that is triggered by a period of physical exertion. EIB occurs mainly in individuals with other features of asthma but is especially prominent in a subset of asthmatics with pronounced indirect airway hyperresponsiveness. Leukotrienes (LTs) play a critical role in the pathophysiology of EIB. Asthmatics who are susceptible to EIB have increased levels of cysteinyl LTs (cysLTs [ie, LTs C4, D4, and E4]) in induced sputum and exhaled breath condensate. Exercise challenge in individuals susceptible to this disorder initiates the sustained increase in cysLTs in the airways and an increase in the ratio of cysLTs to prostaglandin E(2). The effects of cysLTs leading to secreted mucin release and smooth muscle constriction may be mediated in part through activation of sensory nerves. Therapies that block cysLT production or the cysLT(1) receptor effectively reduce the severity of EIB.

Complementary therapy in asthma: inhaled corticosteroids and what?

PURPOSE OF REVIEW

For optimal asthma control, complementary strategies are advocated to cover several aspects of the disease. This mini-review highlights different complementary strategies with special focus on the combined use of inhaled corticosteroids (ICSs) and long-acting beta2 agonists and as an alternative, the combination of ICSs and antileukotrienes.

RECENT FINDINGS

New data show that combinations of ICSs/long-acting beta2 agonists or ICSs with antileukotrienes improve disease stability with concomitant control of the underlying airway inflammation. Moreover, there is some evidence that combination therapy may prevent some aspects of airway remodelling. The use of a fixed combination of both a reliever and a controller medication may have certain advantages compared with a fixed dose regime with as-needed separate reliever therapy. Alternatively, in some asthma phenotypes, such as combined allergic rhinitis and asthma syndrome, the combination of ICSs with antileukotrienes offers a complementary anti-inflammatory treatment in combination with controller effects on both airway compartments.

SUMMARY

This review compares different strategies of complementary therapy in asthma with special focus on how to achieve the best clinical control also aimed at controlling the underlying airway inflammation. We have chosen to focus on two major topics: the use of ICSs and long-acting beta2 agonists in two different strategies, that is, a symptom-driven versus a fixed symptom-preventive approach; and the use of ICSs with a long-acting beta2 agonist versus ICSs and a leukotriene receptor antagonist. What regime should be chosen is highly dependent on the individual phenotype and defined treatment goal.

Evaluating combination therapies for asthma: pros, cons, and comparative benefits

Combination therapies with inhaled corticosteroids (ICS) and either long-acting beta2 agonists (LABA) or leukotriene receptor antagonists (LTRA) are commonly used to help patients maintain control of their asthma. LABA and LTRA have different mechanisms of action and both provide complementary benefits when combined with ICS. This paper compares the two regimens based on recent clinical trial data, evaluates their efficacy on various clinical and quality of life outcomes, and discusses the importance of therapy choice in people with specific asthma phenotypes. The potential of new dosing strategies, including adjustable maintenance therapy and single-inhaler maintenance and reliever therapy is also reviewed. Given the variety of outcomes, phenotypes, and treatment strategies that must be considered, the importance of individualized management is emphasized.

Phenotypic predictors of long-term response to inhaled corticosteroid and leukotriene modifier therapies in pediatric asthma

BACKGROUND

In children with mild-to-moderate persistent asthma, identification of phenotypic predictors to guide selection of a controller regimen is essential.

OBJECTIVE

We sought to identify phenotypic characteristics having predictive value for the difference in treatment responses between twice-daily fluticasone and once-daily montelukast.

METHODS

Data from the Pediatric Asthma Controller Trial were assessed with multivariate analysis. Outcomes included the change in asthma control days (ACDs), FEV(1), peak expiratory flow, and time to first asthma exacerbation measured over a 1-year treatment period.

RESULTS

The mean age was 9.6 +/- 2.1 years, 60% were male, 50% had a parental history of asthma, and 78% had positive aeroallergen skin prick test responses. The mean percent predicted prebronchodilator FEV(1) was 97.8% +/- 12.9%, the median PC(20) value was 0.93 mg/mL, and the median exhaled nitric oxide (eNO) level was 25.2 ppb. A history of parental asthma best predicted the expected treatment benefit with fluticasone compared with montelukast in terms of gain in ACDs (adjusted P = .02) and time to first exacerbation (adjusted P = .05). Increased baseline eNO levels predicted the differential treatment response for fluticasone regarding the gain in ACDs (adjusted P = .01). Prior inhaled corticosteroid (ICS) use (adjusted P = .01) and low PC(20) values (adjusted P = .03) each predicted the expected treatment benefit with fluticasone over montelukast regarding time to first exacerbation. No phenotypic characteristics predicted treatment benefits for montelukast over fluticasone for either outcome.

CONCLUSIONS

Physicians treating children with a parental history of asthma, increased eNO levels, low PC(20) values, or a history of ICS use can expect the best long-term outcomes with ICS therapy compared with treatment with leukotriene receptor antagonists.

Use of prescription drugs in athletes

Although athletes are young and generally healthy, they use a variety of non-doping classified medicines to treat injuries, cure illnesses and obtain a competitive edge. Athletes and sports medicine physicians try to optimize the treatment of symptoms related to extreme training during an elite athlete's active career. According to several studies, the use of antiasthmatic medication is more frequent among elite athletes than in the general population. The type of training and the kind of sport influence the prevalence of asthma. Asthma is most common among those competing in endurance events, such as cycling, swimming, cross-country skiing and long-distance running. Recent studies show that athletes use also NSAIDs and oral antibacterials more commonly than age-matched controls, especially athletes competing in speed and power sports. Inappropriately high doses and concomitant use of several different NSAIDs has been observed. All medicines have adverse effects that may have deleterious effects on elite athletes' performance. Thus, any unnecessary medication use should be minimized in elite athletes. Inhaled beta(2)-agonists may cause tachycardia and muscle tremor, which are especially harmful in events requiring accuracy and a steady hand. In experimental animal models of acute injury, especially selective cyclo-oxygenase-2 inhibitors have been shown to be detrimental to tissue-level repair. They have been shown to impair mechanical strength return following acute injury to bone, ligament and tendon. This may have clinical implications for future injury susceptibility. However, it should be noted that the current animal studies have limited translation to the clinical setting. Adverse effects related to the CNS and gastrointestinal adverse reactions are commonly reported in connection with NSAID use also in elite athletes. In addition to the potential for adverse effects, recent studies have shown that NSAID use may negatively regulate muscle growth by inhibiting protein synthesis. Physicians and pharmacists taking care of athletes' medication need to be aware of the medicines that an athlete is taking and how those medicines interact with performance, exercise, environment and other medicines. Sport associations should repeatedly monitor not only the use of banned substances, but also the trends of use of legal medicines in athletes. Not only physicians and pharmacists, but also athletes and coaches should be better educated with respect to potential benefits and risks, and how each agent may affect an athlete's performance. The attitudes and beliefs leading to ample use of legal medicines in athletes is an interesting area of future research.

Regular treatment with salmeterol for chronic asthma: serious adverse events

BACKGROUND

Epidemiological evidence has suggested a link between beta-agonists and increases in asthma mortality. There has been much debate about possible causal links for this association, and whether regular (daily) long-acting beta(2)-agonists are safe.

OBJECTIVES

The aim of this review is to assess the risk of fatal and non-fatal serious adverse events in trials that randomised patients with chronic asthma to regular salmeterol versus placebo or regular short-acting beta(2)-agonists.

SEARCH STRATEGY

Trials were identified using the Cochrane Airways Group Specialised Register of trials. Web sites of clinical trial registers were checked for unpublished trial data and FDA submissions in relation to salmeterol were also checked. The date of the most recent search was October 2007.

SELECTION CRITERIA

Controlled parallel design clinical trials on patients of any age and severity of asthma were included if they randomised patients to treatment with regular salmeterol and were of at least 12 weeks duration. Concomitant use of inhaled corticosteroids was allowed, as long as this was not part of the randomised treatment regimen.

DATA COLLECTION AND ANALYSIS

Two authors independently selected trials for inclusion in the review. Outcome data was extracted by one author and checked by the second author. Unpublished data on mortality and serious adverse events was sought.

MAIN RESULTS

The review includes 26 trials comparing salmeterol to placebo and 8 trials comparing with salbutamol. These included 62,630 participants with asthma (including 2,380 children). In 6 trials (2,766 patients), no serious adverse event data could be obtained. All cause mortality was higher with regular salmeterol than placebo but the increase was not significant, Odds Ratio 1.33 [95% CI: 0.85, 2.10]. Non-fatal serious adverse events were significantly increased when regular salmeterol was compared with placebo, Odds Ratio 1.14 [95% CI: 1.01, 1.28]. One extra serious adverse event occurred over 28 weeks for every 188 people treated with regular salmeterol [95% CI: 95 to 2606]. There is insufficient evidence to assess whether the risk in children is higher or lower than in adults. No significant increase in fatal or non-fatal serious adverse events was found when regular salmeterol was compared with regular salbutamol. Individual patient data from the SNS study have been combined with the results of the SMART study; in patients who were not taking inhaled corticosteroids, compared to regular salbutamol or placebo, there was a significant increase in risk of asthma-related death with regular salmeterol, Odds Ratio 9.52 [95% CI: 1.24, 73.09]. The confidence interval for patients taking inhaled corticosteroids is too wide to rule out an increase in asthma mortality in this group.

AUTHORS' CONCLUSIONS

In comparison with placebo, we have found an increased risk of serious adverse events with regular salmeterol. There is also a clear increase in risk of asthma-related mortality in patients not using inhaled corticosteroids in the two large surveillance studies. Although the increase in asthma-related mortality was smaller in patients taking inhaled corticosteroids at baseline, the confidence interval is wide, so it cannot be concluded that the inhaled corticosteroids abolish the risks of regular salmeterol. The adverse effects of regular salmeterol in children remain uncertain due to the small number of children studied.

Pretreatment with albuterol versus montelukast for exercise-induced bronchospasm in children

STUDY OBJECTIVES

To compare pretreatment with albuterol versus montelukast added to the current asthma regimen for protection against exercise-induced bronchospasm in children with mild-to-moderate asthma, and to determine whether cysteinyl leukotriene (Cys-LT) concentrations measured in the exhaled breath condensate correlated with response to montelukast.

DESIGN

Prospective, randomized, double-blind, double-dummy, crossover study.

SETTING

Asthma clinic at a university-affiliated medical center.

PATIENTS

Eleven children aged 7-17 years with physician-diagnosed mild-to-moderate asthma for at least 6 months and with self-reported exercise-induced bronchospasm (defined as > or = 15% decrease in forced expiratory volume in 1 sec [FEV(1)] at screening and baseline visit).

INTERVENTION

Patients were randomly assigned to receive 3-7 days of oral montelukast 5-10 mg/day or 2 puffs of an albuterol metered-dose inhaler just before an exercise challenge and then were crossed over to the alternate therapy for the last visit.

MEASUREMENTS AND MAIN RESULTS

Serial spirometry was performed before and at 0, 5, 10, 15, 30, 45, and 60 minutes after the exercise challenge at each visit. Measurement of exhaled breath condensate was performed at the screening visit and study visits 1 and 2. The primary outcome was the maximum change in FEV(1) after exercise. Secondary outcomes were the area under the curve for FEV(1) (expressed as percentage decrease from baseline) during the first 60 minutes (AUC(0-60)) after exercise and the proportion of patients in whom exercise-induced bronchospasm was prevented (defined as < 15% decrease in FEV(1) after exercise challenge). The mean +/- SD maximum decrease in FEV(1) was 27.5 +/- 7.9% at baseline. Patients receiving montelukast had an 18.3 +/- 13.7% decrease in FEV(1) compared with 0.7 +/- 1.6% in patients receiving albuterol (p=0.002, paired t test). Exercise-induced bronchospasm was prevented in 100% of the patients receiving albuterol compared with 55% receiving montelukast (p<0.05, McNemar's test). The AUC(0-60) was significantly smaller with albuterol compared with montelukast (p<0.001, Wilcoxon signed rank test). No correlations were found between Cys-LT concentration and the severity of exercise-induced bronchospasm or the response to montelukast.

CONCLUSION

Pretreatment with albuterol is more effective than montelukast for prevention of exercise-induced bronchospasm in children with asthma.

Treatment of exercise-induced asthma, respiratory and allergic disorders in sports and the relationship to doping: Part II of the report from the Joint Task Force of European Respiratory Society (ERS) and European Academy of Allergy and Clinical Immunology (EAACI) in cooperation with GA(2)LEN

AIM

The aims of part II is to review the current recommended treatment of exercise-induced asthma (EIA), respiratory and allergic disorders in sports, to review the evidence on possible improvement of performance in sports by asthma drugs and to make recommendations for their treatment.

METHODS

The literature cited with respect to the treatment of exercise induced asthma in athletes (and in asthma patients) is mainly based upon the systematic review given by Larsson et al. (Larsson K, Carlsen KH, Bonini S. Anti-asthmatic drugs: treatment of athletes and exercise-induced bronchoconstriction. In: Carlsen KH, Delgado L, Del Giacco S, editors. Diagnosis, prevention and treatment of exercise-related asthma, respiratory and allergic disorders in sports. Sheffield, UK: European Respiratory Journals Ltd, 2005:73-88) during the work of the Task Force. To assess the evidence of the literature regarding use of beta(2)-agonists related to athletic performance, the Task Force searched Medline for relevant papers up to November 2006 using the present search words: asthma, bronchial responsiveness, exercise-induced bronchoconstriction, athletes, sports, performance and beta(2)-agonists. Evidence level and grades of recommendation were assessed according to Sign criteria.

RESULTS

Treatment recommendations for EIA and bronchial hyper-responsiveness in athletes are set forth with special reference to controller and reliever medications. Evidence for lack of improvement of exercise performance by inhaled beta(2)-agonists in healthy athletes serves as a basis for permitting their use. There is a lack of evidence of treatment effects of asthma drugs on EIA and bronchial hyper-responsiveness in athletes whereas extensive documentation exists in treatment of EIA in patients with asthma. The documentation on lack of improvement on performance by common asthma drugs as inhaled beta(2)-agonists with relationship to sports in healthy individuals is of high evidence, level (1+).

CONCLUSIONS

Exercise induced asthma should be treated in athletes along same principles as in ordinary asthma patients with relevance to controller and reliever treatment after careful diagnosis. There is very high level of evidence for the lack of improvement in athletic performance by inhaled beta2-agonists.

Angiopoietin-2 as a contributing factor of exercise-induced bronchoconstriction in asthmatic patients receiving inhaled corticosteroid therapy

BACKGROUND

Airway microcirculation has the potential to contribute to the pathogenesis of exercise-induced bronchoconstriction (EIB) in asthma. Recently, angiopoietin-1 has been found to stabilize microvessels and make them leak resistant, whereas angiopoietin-2 is an antagonist of angiopoietin-1 and enhances microvascular permeability.

OBJECTIVE

We sought to examine the roles of angiopoietin-2 in EIB in asthmatic patients with inhaled corticosteroid therapy.

METHODS

Levels of angiopoietin-1 and angiopoietin-2 in induced sputum were examined in 32 asthmatic patients who were receiving inhaled corticosteroid therapy for more than 6 months at the entry of this study and 14 healthy control subjects. All asthmatic patients performed an exercise test.

RESULTS

The degree of eosinophilic airway inflammation did not differ significantly between asthmatic patients and healthy control subjects. Angiopoietin-1 levels were also similar in the 2 groups (asthmatic patients: median, 6.0 ng/mL [range, 2.0-10.7 ng/mL]; healthy control subjects: median, 4.2 ng/mL [range, 1.5-10.7 ng/mL]). In contrast, angiopoietin-2 levels were significantly higher in asthmatic patients than in healthy control subjects (asthmatic patients: median, 0.74 ng/mL [range, 0.3-1.2 ng/mL]; healthy control subjects: median, 0.26 ng/mL [range, 0.05-0.47 ng/mL]; P < .001). There was no significant correlation between angiopoietin-1 levels and the severity of EIB in asthmatic patients. However, angiopoietin-2 levels were significantly correlated with the severity of EIB and airway microvascular permeability index.

CONCLUSION

Angiopoietin-2 levels were increased in the airways of asthmatic patients with inhaled corticosteroid therapy, and its levels were associated with the severity of EIB.

Single-Dose Montelukast or Salmeterol as Protection Against Exercise-Induced Bronchoconstriction

BACKGROUND AND OBJECTIVE

It has been previously established that montelukast provides protection against exercise-induced bronchoconstriction (EIB) after a single dose. The present objective was to assess the onset and duration of this protective action in a trial that included both positive and negative controls.

METHODS

A randomized, active-controlled and placebo-controlled, double-blind, double-dummy, three-way crossover study was conducted in 47 patients (age range, 15 to 44 years) in whom there was a 20 to 40% fall in FEV(1) following exercise (DeltaFEV(1)). In randomized sequence, patients received oral montelukast (10 mg), placebo, or inhaled salmeterol (50 microg) as a positive control. Dosing was followed by exercise challenges at 2, 8.5, and 24 h. The primary end point was maximum DeltaFEV(1) at 2 h postdose. Secondary end points included maximum DeltaFEV(1) at the two later time points, and other measures (including recovery time and need for beta-agonist rescue) at all time points.

RESULTS

The maximum DeltaFEV(1) magnitudes at 2, 8.5, and 24 h were significantly smaller after montelukast administration than after placebo administration (least squares mean [+/- SE], 13.2 +/- 1.2%, 11.7 +/- 1.2%, and 10.0 +/- 1.1% vs 21.8 +/- 1.2%, 16.8 +/- 1.3%, and 14.0 +/- 1.1%, respectively; p <or= 0.001, < 0.01, and < 0.05). All secondary end point results supported the primary end point. Montelukast and salmeterol had similar efficacy at 2 and 8.5 h, but only montelukast was effective at 24 h.

CONCLUSION

Montelukast provided significant protection against EIB having an onset within 2 h following a single oral dose and lasting for at least 24 h.

Update on montelukast and its role in the treatment of asthma, allergic rhinitis and exercise-induced bronchoconstriction

Montelukast sodium (Singulair, Merck and Co., Inc., Whitehouse Station, NJ) is a selective and orally-active leukotriene receptor antagonist with demonstrated effectiveness for treating allergic asthma and allergic rhinitis in adults and children as young as 12 months of age for allergic asthma and 6 months of age for allergic rhinitis. It was recently approved in the US for prevention of exercise-induced bronchoconstriction in patients who are > or = 15 years of age. This paper updates a prior review of the data on the clinical efficacy of montelukast published in this journal.