Montelukast for the treatment of asthma in the adult population

INTRODUCTION

Asthma is a complex process that results from airway inflammation and manifests as bronchoconstriction. Infiltration of the airway mucosa and lumen by activated inflammatory cells, along with release of mediators, can occur extensively. Chemical mediators known as leukotrienes are believed to play a major role in this process. At present, inhaled corticosteroids (ICS) are the pharmacologic cornerstone of asthma management. However, asthma control may remain suboptimal when relying on ICS because of problems with compliance, poor inhaler technique and concerns about the side effects of steroids; additional agents are often required to control symptoms. Leukotriene receptor antagonists (LTRA), namely montelukast, provide a safe and effective additional anti-inflammatory treatment option. There is particular benefit for patients with asthma and concomitant allergic rhinitis.

AREAS COVERED

Montelukast has been well studied through rigorous clinical trials. A thorough review of the literature has been undertaken to assess the evidence supporting the use of LTRAs. This review focuses on the role of montelukast not only as monotherapy but also as add-on therapy to ICS in the adult asthma population, as well as adult asthmatics with concomitant allergic rhinitis. In addition, there is often some discrepancy between the evidence generated in the idealized asthma patients recruited into randomized clinical trials and results obtained in the real-life setting. This review assesses recent clinical trials evaluating the real-life evaluation of montelukast, achieved mainly through open-label observational studies.

EXPERT OPINION

Oral LTRA bring remarkable ease of anti-inflammatory treatment administration and symptom improvement with minimal side effects to the management of adult asthma. Basic asthma mechanisms and much-valued scientific groundwork has been identified by exploring target asthma treatment with anti-leukotriene therapy. This will have a significant impact in the future development of targeted asthma therapies as well as the current management of asthma and other inflammatory medical conditions.

[Prevalence and characteristics of rhinitis in adult asthmatic patients attending allergist, primary care and pulmonologist settings in Spain (AIR study)]

BACKGROUND AND OBJECTIVES

Rhinitis and asthma are linked by common epidemiological, clinical and inflammatory features. The objective of the AIR study was to understand the prevalence and characteristics of rhinitis in adult asthmatic patients who were seen in either primary or secondary care (Allergy or Pulmonology) in Spain.

PATIENTS AND METHODS

This was a prospective epidemiological study with the participation of 1,369 randomly selected physicians. Five thousand six hundred sixteen asthmatic patients older than 18 years of age were selected and the study was carried out between February-September 2006. Demographic data, rhinitis prevalence, pulmonary function, allergy tests and treatments were analyzed.

RESULTS

Some 75% (N=4,212) of the asthmatic patients presented with additional rhinitis and these were characterised as being both younger (41.3 vs 50.4 years; p<0.0001) and with less severe asthma (FEV(1)=86.6 vs 79.3%, p<0.0001) than asthmatic patients without rhinitis. A positive correlation was found between asthma and rhinitis severity (p<0.0001) whilst atopy was significantly associated with the presence of rhinitis (81 vs 48%; OR: 4.80; CI 95%: 4.2-5.5). The presence of co-morbid rhinitis was associated with a higher number of asthma exacerbations (p<0.001).

CONCLUSIONS

Some 75% of our asthmatic patients had associated rhinitis and this association was more frequent in atopic subjects. There is a positive correlation between the severity of rhinitis and asthma and between the number of asthma exacerbations and the presence of rhinitis. These results support the main message of ARIA and GEMA recommendations regarding the integral management of airways to improve the control of asthma.

Allergic rhinitis and asthma ad hoc survey: clinical and psychological perspectives

BACKGROUND

Several studies have provided evidence of a strong association between asthma and rhinitis, with consequences in terms of therapy and disease management.

OBJECTIVES

The aims of our study were to evaluate physicians' knowledge about rhinitis/asthma comorbidity, to note the patients' management behaviour and to assess the patients' experience about symptoms and expectations, and to investigate the clinical and psychological meaning of general practitioners' and patients' awareness.

METHODS

One hundred and one general practitioners and 504 asthmatic patients participated in the study. General practitioners and patients filled in two different multiple choice questionnaires concerning asthma-rhinitis link and impact.

RESULTS

34.7% of general practitioners are aware of the link between asthma and rhinitis, and 43.6% of them hypothesize the comorbidity on the basis of their clinical experience. 21.8% of physicians make the diagnosis autonomously. 27.8% of asthmatic patients experience three or less rhinitic symptoms, 41% from four to six symptoms and 31.2 more than six symptoms. These symptoms deeply interfere with daily life, causing sleep problems (87.3%), lack of concentration (78.9%), difficulties in spare time (71.8%) and sport (71.7%). Rhinitis symptoms are responsible for the worsening of asthma, with an increase in dyspnoea (86.3%), cough (73.9%), and wheezing (59%). Ninety-three percent of patients expressed an interest in a combination therapy approach.

CONCLUSIONS

Asthma and rhinitis interact in the development of clinical burden and impact on quality of life. The survey results showed different perspectives when evaluated from clinical and psychological points of view.

Burden of concomitant allergic rhinitis in adults with asthma

Asthma (A) and allergic rhinitis (AR) are common conditions with evidence of shared epidemiological and patho-physiological backgrounds. A systematic review of the literature in the last three decades was performed to summarize both the prevalence and the economic burden of concomitant AR in adult patients with asthma. The reported prevalence estimates of concomitant AR in patients with asthma in the United States and in Europe studies is in excess of 50%, with up to 100% prevalence reported in patients with allergic asthma. In these populations, asthma-related medical resource use, including asthma attacks, emergency room visits, physician visits, and prescription medication use, is higher among asthmatic patients with concomitant AR compared to those without AR. These patients also experience more frequent absence from work and decreased productivity. A low prevalence (6.2%) of comorbid AR in people with asthma has been reported in a single study from Asia. A combined treatment strategy as recommended by international guidelines may improve asthma outcomes in asthmatic patients with concomitant AR.

Nasal symptoms, airway obstruction and disease severity in chronic obstructive pulmonary disease

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is characterized by inflammation of the lung in association with airflow obstruction. There is increasing evidence of upper airway involvement in COPD and we have reported that this nasal inflammation is proportional to that in the lung. Given recognized relationships between lower airway inflammation and spirometric indices such as the Forced Expiratory Volume in one second (FEV(1)), we hypothesized that there may be a relationship between nasal obstruction and FEV(1) in COPD. We also sought to investigate relationships between nasal symptoms and nasal patency in COPD.

METHODS

We assessed the nasal and pulmonary airways, using acoustic rhinometry and spirometry respectively, in 51 patients with COPD.

RESULTS

The presence of chronic nasal symptoms in COPD was associated with reduced nasal patency (6.04 cm(2) symptoms vs. 9.55 cm(2) no symptoms, at the second minimum cross-sectional area, P = 0.049). Nasal patency in COPD was inversely proportional to pulmonary airflow obstruction, and therefore to COPD disease severity (e.g. FEV(1)% predicted vs. second minimum cross-sectional area, r = 0.36, P = 0.009).

CONCLUSIONS

The degree of nasal airway obstruction in COPD reflects the impairment to pulmonary airflow, and is greater in the presence of chronic nasal symptoms. This study provides further evidence of pan-airway involvement in COPD.

Increased risk of asthma attacks and emergency visits among asthma patients with allergic rhinitis: a subgroup analysis of the investigation of montelukast as a partner agent for complementary therapy [corrected]

BACKGROUND

Inadequately controlled allergic rhinitis (AR) in asthmatic patients can contribute towards increased asthma exacerbations and poorer symptom control, which may increase medical resource use. We assessed asthma-related medical resource use and attacks in asthmatic patients who did and did not have concomitant AR and were adding montelukast or salmeterol to baseline treatment with inhaled fluticasone.

METHODS

A post hoc resource use analysis of a 52-week, double-blind multicentre clinical trial (Investigation of Montelukast as a Partner Agent for Complementary Therapy) [corrected] including 1490 adults with chronic asthma, aged 15-72 years, with FEV(1) 50-90% of predicted and > or =12% increase in FEV(1) after salbutamol administration, treated with either montelukast 10 mg daily or salmeterol 50 microg twice daily in addition to fluticasone 200 microg, was undertaken. Asthma-related medical resource use included medical visits (defined as either an unscheduled visit [to a general practitioner, a specialist or a non-medical provider] or a specialist visit), emergency room visits and hospitalizations during follow-up. Asthma attacks were defined as the worsening of asthma requiring unscheduled visit, emergency visit, hospitalization or oral/intravenous/intramuscular corticosteroids.

RESULTS

A self-reported history of concomitant AR was identified in 60% of the patients (n=893). Univariate analysis suggests that significantly more patients with concomitant AR experienced emergency room visits (3.6% vs. 1.7%, P=0.029) and asthma attacks (21.3% vs. 17.1%, P=0.046). Multivariate analysis adjusting for treatment group, age and baseline asthma severity confirmed these results since the presence of concomitant AR in patients with asthma increases the likelihood of emergency room visit (odds ratio (OR)=2.35, 95% confidence interval (CI)=1.12-4.80) and asthma attack (OR=1.35, 95% CI=1.03-1.77). Patients with asthma alone compared with patients with both conditions did not differ in terms of unscheduled or specialist visits and hospitalizations.

CONCLUSIONS

Presence of self-reported concomitant AR in patients with asthma resulted in a higher rate of asthma attacks and more emergency room visits compared with asthma patients without concomitant AR.

Efficacy and safety of montelukast in adults with asthma and allergic rhinitis

Several clinical studies have confirmed the effectiveness of montelukast 10mg orally in adults with both asthma and allergic rhinitis. The objective of this phase IV study was to investigate the efficacy and safety of montelukast 10mg in adults with both asthma and allergic rhinitis in a real-life setting. Data from 5855 patients (mean age: 42.8+/-15.4 years) were collected and analyzed following treatment for 4-6 weeks. Efficacy was analyzed by comparing baseline values of: general, day- and night-time improvement in asthma symptoms, need for rescue medication or inhaled corticosteroids (ICSs), general and specific improvement in allergic rhinitis symptoms, reduction in rhinitis medication use, and general and specific quality of life (QoL) improvement with values collected at the end of the observation period of 4-6 weeks. Following treatment with 10mg montelukast 86.5% (n=4547) of patients reported a strong or marked improvement in day-time asthma symptoms and 88.5% (n=4367) reported improvement in night-time symptoms. A similarly high proportion of patients had a strong or marked improvement in all symptoms of allergic rhinitis (i.e. sneezing/itching (84%), rhinorrhea (81.7%), nasal congestion (79.3%), watery eyes (78.4%) and red or burning eyes (77.7%). The use of asthma and rhinitis medication was also reduced. 92.3% (n=5685) of all patients intended to continue montelukast therapy. Overall QoL was "very good" or "good" in 85.2% of patients (n=4991) and a "strong" or "marked" improvement in each of the four domains of sleep, work, everyday life and physical activity. Montelukast was well tolerated. Adverse drug reactions occurred in 14 out of 6158 patients. None of the adverse events was serious. Accordingly, montelukast 10mg is a safe and effective treatment for patients with both asthma and allergic rhinitis.

Systemic and upper and lower airway inflammation at exacerbation of chronic obstructive pulmonary disease

RATIONALE

In addition to pulmonary involvement, stable chronic obstructive pulmonary disease (COPD) is associated with nasal and systemic inflammation. Although exacerbations of COPD are associated with increased pulmonary and systemic inflammation, determinants of the systemic response remain obscure, and nor is it known whether there is nasal involvement.

OBJECTIVES

To investigate upper airway, lower airway, and systemic inflammation at exacerbation of COPD.

METHODS

We sampled sputum, nasal wash, and serum from 41 exacerbations (East London cohort) for analysis of pathogenic microorganisms and inflammatory indices (sputum/nasal wash leukocytes, interleukin [IL]-6, IL-8, and myeloperoxidase; serum IL-6 and C-reactive protein). Values were compared with stable COPD.

MEASUREMENTS AND MAIN RESULTS

Exacerbation of COPD is associated with greater nasal, sputum, and serum inflammation than the stable state. At exacerbation, inflammatory markers were highly correlated within nasal wash and serum (all r >/= 0.62, p < 0.001), but not sputum. The degree of upper airway inflammation correlated with the degree of lower airway inflammation (e.g., nasal wash/sputum myeloperoxidase; r = 0.50, p = 0.001). The degree of systemic inflammation correlated with the degree of lower airway inflammation (e.g., serum IL-6/sputum IL-8; r = 0.35, p = 0.026), and was greater in the presence of a sputum bacterial pathogen (29.0 g/dl C-reactive protein difference, p = 0.002). We did not find relationships between the upper airway and systemic compartments.

CONCLUSIONS

Exacerbation of COPD is associated with pan-airway inflammation; the systemic inflammatory response is proportional to that occurring in the lower airway and greater in the presence of a bacterial pathogen.