Anticholinergic agents for chronic asthma in adults

Bronchodilator Responsiveness Measured by Spirometry and Impulse Oscillometry in Patients with Asthma After Short Acting Antimuscarinic and/or Beta-2-Agonists Inhalation

Background

Bronchodilator responsiveness (BDR) in asthma involves both the central and peripheral airways but is primarily relieved with beta-2-agonists and evaluated by spirometry. To date, antimuscarinics can be added as a reliever medication in more severe asthma. We hypothesize that combining both short-acting beta-2 agonist (SABA) and short-acting muscarinic antagonist (SAMA) could also improve the responsiveness in mild-moderate asthma. Therefore, we aimed to compare the direct effects of inhaling SABA alone, SAMA alone or combining both SABA and SAMA on the central and peripheral airways in asthma.

Methods

Twenty-three patients with mild-moderate BDR in asthma performed dynamic spirometry and impulse oscillometry before (baseline) and multiple timepoints within an hour after inhalation of SABA (salbutamol), SAMA (ipratropium bromide), or both SABA and SAMA at three different visits.

Results

The use of SAMA alone did not show any improvement compared to the use of SABA alone. Inhalation of SABA+SAMA, however, averaged either similar or better BDR than SABA alone in FEV1, MMEF, FVC, R5, R20 and R5-R20. Inhaling SABA+SAMA reached a stable BDR in more patients within 0-10 minutes and also reached the FEV1 (Δ%)>12% faster (3.5 minutes) than inhaling SABA alone (5.1 minutes). Inhaling SABA+SAMA was significantly better than SAMA alone in FEV1 (p = 0.015), MMEF (p = 0.0059) and R20 (p = 0.0049). Using these three variables highlighted a subgroup (30%, including more males) of patients that were more responsive to inhaling SABA+SAMA than SABA alone.

Conclusion

Overall, combining SAMA with SABA was faster and more consistent at increasing the lung function than SABA alone or SAMA alone, and the additive effect was best captured by incorporating peripheral-related variables. Therefore, SAMA should be considered as an add-on reliever for mild-moderate patients with BDR in asthma.

Might It Be Appropriate to Anticipate the Use of Long-Acting Muscarinic Antagonists in Asthma?

A growing number of clinical trials are documenting that adding a long-acting muscarinic antagonist (LAMA) to established asthma treatment with an inhaled corticosteroid (ICS) and a long-acting β₂-agonist (LABA) is a treatment option that improves the health of patients with uncontrolled severe asthma even when therapy is optimized. These favorable results are the reason why the leading guidelines recommend triple therapy with ICS + LABA + LAMA in patients with asthma uncontrolled by medium- to high-dose ICS-LABA. However, we suggest adding LAMAs to ICS-LABAs at an earlier clinical stage. Such action could positively influence airflow limitation, exacerbations, and eosinophilic inflammation, conditions that are associated with acetylcholine (ACh) activity. It could also interrupt the vicious cycle related to a continuous release of ACh leading to the progressive expansion of neuronal plasticity resulting in small airway dysfunction. The utility of an earlier use of triple therapy in asthma should, in any case, be confirmed by statistically powered trials.

Tiotropium in the management of paediatric and adolescent asthma: Systematic review

Tiotropium bromide is a long-acting muscarinic antagonist (LAMA) and is the only LAMA licensed for management for patients' ≥6 years old with severe asthma who have experienced one or more severe asthma exacerbations in the preceding year. Recent clinical trials have demonstrated that once-daily tiotropium is safe and efficacious in 6-17 year-olds with symptomatic asthma despite treatment with inhaled corticosteroids (ICSs), with or without additional controllers. In this paper, we review the evidence of the safety and efficacy of tiotropium add-on maintenance treatment in children and adolescents with symptomatic moderate and severe asthma.

Future perspectives of anticholinergics for the treatment of asthma in adults and children

Despite major advances in therapeutic interventions and the availability of detailed treatment guidelines, a high proportion of patients with symptomatic asthma remain uncontrolled. Asthma management is largely guided by the Global Initiative for Asthma (GINA) strategy and is based on a backbone of inhaled corticosteroid (ICS) therapy with the use of additional therapies to achieve disease control. Inhaled long-acting bronchodilators alone and in combination are the preferred add-on treatment options. Although long-acting muscarinic antagonists (LAMAs) are a relatively recent addition to disease management recommendations for asthma, tiotropium has been extensively studied in a large clinical trial program. In Europe and the United States, tiotropium is approved for patients aged ≥6 years and uncontrolled on medium- to high-dose ICS/long-acting β2-agonists at GINA Steps 4 and 5 with a history of exacerbations. Evidence supports the efficacy of tiotropium Respimat® in adults in terms of lung function and asthma control, with a safety profile comparable with that of placebo across a range of asthma severities. Similarly, clinical trials in patients aged 1-17 years have shown improvements in lung function and trends toward improved asthma control. Furthermore, its efficacy makes tiotropium relatively easy to incorporate into routine clinical practice, irrespective of allergic status and without the need for patient phenotyping. Tiotropium is a cost-effective treatment that may offer an important alternative to other, more expensive add-on therapies. This review discusses the potential future position of LAMAs in clinical practice by considering the continuously evolving evidence. Prominence is given to tiotropium, the only LAMA supported by a structured clinical trial program in asthma to date, while also considering other recommended treatment options for patients with uncontrolled asthma. The importance of effective patient/caregiver-clinician communication and shared decision-making in enhancing treatment adherence is also highlighted.

Therapeutic Effects of a Long-Acting Cholinergic Receptor Blocker, Tiotropium Bromide, on Asthma

Background

The aim of this study was to evaluate the therapeutic effects of tiotropium bromide on asthma.

Material/Methods

A total of 160 patients with moderate persistent asthma were randomly divided into 4 groups (n=40): the 3 control groups were given fluticasone propionate aerosol (group A), salmeterol-fluticasone propionate inhalant (group B), and tiotropium bromide inhalation powder combined with salmeterol-fluticasone propionate inhalant (group C), respectively, and the experimental group received tiotropium bromide inhalation powder combined with fluticasone propionate aerosol (group D) and salbutamol was used to relieve symptoms when necessary.

Results

After 8 weeks of treatment, the pulmonary function of group D, which was significantly better than those of group A (P<0.05), was similar to those of groups B and C (P>0.05). Group D had significantly better asthma control test scores and nighttime symptom scores than in group A (P<0.05), without significant differences from those of group B or group C (P>0.05). The number of times salbutamol was used to alleviate symptoms was significantly different (P<0.05) between group D and group A (P<0.05), as well as between group C and group D (P<0.05). Groups D and B had similar results (P>0.05). IL-13 levels in induced sputum had significant differences (P<0.05). The levels in group D, which were higher than those of groups A and B (P<0.05), were similar to those of group C (P>0.05).

Conclusions

Tiotropium bromide combined with fluticasone propionate improved the respiratory function and quality of life, and is a new therapy for moderate, persistent asthma.

Tiotropium for the Treatment of Asthma: Patient Selection and Perspectives

Asthma is a chronic disease of airway inflammation with a large global burden. Despite established, guideline-based stepwise therapy, a significant proportion of patients remain symptomatic and poorly controlled. As such, there is a need for additional safe, effective, convenient, and cost-effective therapies that can be broadly applied across a range of asthma phenotypes. Tiotropium is a long-acting muscarinic antagonist (LAMA) that leads to bronchodilation by blocking endogenous acetylcholine receptors in the airways. Tiotropium has long been approved for the treatment of chronic obstructive pulmonary disease, and it has recently been recognized for its safety and efficacy in improving lung function and controlling asthma. Evidence from several Phase III trials in the adult and paediatric population has shown that tiotropium is well tolerated and significantly improves a range of endpoints as an add-on treatment to ICS therapy, regardless of baseline characteristics and clinical phenotypes. Consequently, regulatory authorities worldwide have recently licensed tiotropium as the only LAMA approved for the treatment of asthma. This review provides an overview of safety and efficacy data and discusses the use of tiotropium in patients across the range of asthma severities, ages, and phenotypes.

Muscarinic Receptor Antagonists

Parasympathetic activity is increased in patients with chronic obstructive pulmonary disease (COPD) and asthma and appears to be the major reversible component of airway obstruction. Therefore, treatment with muscarinic receptor antagonists is an effective bronchodilator therapy in COPD and also in asthmatic patients. In recent years, the accumulating evidence that the cholinergic system controls not only contraction by airway smooth muscle but also the functions of inflammatory cells and airway epithelial cells has suggested that muscarinic receptor antagonists could exert other effects that may be of clinical relevance when we must treat a patient suffering from COPD or asthma. There are currently six muscarinic receptor antagonists licenced for use in the treatment of COPD, the short-acting muscarinic receptor antagonists (SAMAs) ipratropium bromide and oxitropium bromide and the long-acting muscarinic receptor antagonists (LAMAs) aclidinium bromide, tiotropium bromide, glycopyrronium bromide and umeclidinium bromide. Concerns have been raised about possible associations of muscarinic receptor antagonists with cardiovascular safety, but the most advanced compounds seem to have an improved safety profile. Further beneficial effects of SAMAs and LAMAs are seen when added to existing treatments, including LABAs, inhaled corticosteroids and phosphodiesterase 4 inhibitors. The importance of tiotropium bromide in the maintenance treatment of COPD, and likely in asthma, has spurred further research to identify new LAMAs. There are a number of molecules that are being identified, but only few have reached the clinical development.

The evidence on tiotropium bromide in asthma: from the rationale to the bedside

Severe and poorly controlled asthma still accounts for a great portion of the patients affected. Disease control and future risk management have been identified by international guidelines as the main goals in patients with asthma. The need for new treatment approaches has led to reconsider anticholinergic drugs as an option for asthma treatment. Tiotropium is the first anticholinergic drug that has been approved for children and adults with poorly controlled asthma and is currently considered as an option for steps 4 and 5 of the Global Initiative for Asthma. In large randomized clinical trials enrolling patients with moderate to severe asthma, add-on therapy with tiotropium has demonstrated to be efficacious in improving lung function, decreasing risk of exacerbation and slowing the worsening of disease; accordingly, tiotropium demonstrated to be non inferior compared to long acting beta-agonists in the maintenance treatment along with medium to high inhaled corticosteroids. In view of the numerous ancillary effects acting on inflammation, airway remodeling, mucus production and cough reflex, along with the good safety profile and the broad spectrum of efficacy demonstrated in different disease phenotypes, tiotropium can represent a beneficial alternative in the therapeutic management of poorly controlled asthma. The present extensive narrative review presents the pharmacological and pathophysiological basis that guided the rationale for the introduction of tiotropium in asthma treatment algorithm, with a particular focus on its conventional and unconventional effects; finally, data on tiotropium efficacy and safety. from recent randomized clinical trials performed in all age categories will be extensively discussed.

The Danish National Database for Asthma: establishing clinical quality indicators

Asthma is one of the most common chronic diseases worldwide affecting more than 300 million people. Symptoms are often non-specific and include coughing, wheezing, chest tightness, and shortness of breath. Asthma may be highly variable within the same individual over time. Although asthma results in death only in extreme cases, the disease is associated with significant morbidity, reduced quality of life, increased absenteeism, and large costs for society. Asthma can be diagnosed based on report of characteristic symptoms and/or the use of several different diagnostic tests. However, there is currently no gold standard for making a diagnosis, and some degree of misclassification and inter-observer variation can be expected. This may lead to local and regional differences in the treatment, monitoring, and follow-up of the patients. The Danish National Database for Asthma (DNDA) is slated to be established with the overall aim of collecting data on all patients treated for asthma in Denmark and systematically monitoring the treatment quality and disease management in both primary and secondary care facilities across the country. The DNDA links information from population-based disease registers in Denmark, including the National Patient Register, the National Prescription Registry, and the National Health Insurance Services register, and potentially includes all asthma patients in Denmark. The following quality indicators have been selected to monitor trends: first, conduction of annual asthma control visits, appropriate pharmacological treatment, measurement of lung function, and asthma challenge testing; second, tools used for diagnosis in new cases; and third, annual assessment of smoking status, height, and weight measurements, and the proportion of patients with acute hospital treatment. The DNDA will be launched in 2016 and will initially include patients treated in secondary care facilities in Denmark. In the nearby future, the database aims to include asthma diagnosis codes and clinical data registered by general practitioners and specialised practitioners as well.

Tiotropium in asthma: what is the evidence and how does it fit in?

Despite current therapeutic approaches asthma remains uncontrolled in a significant proportion of patients. Short-acting anticholinergic bronchodilators have a very long history of use in asthma, and recent data confirms the importance of acetylcholine as both a bronchoconstrictor and as a regulator of inflammation and remodeling in the lungs. Data from a comprehensive clinical trial programme, as well as use in primary care, show the efficacy and safety of tiotropium in adults with mild to moderate asthma when it is added to ICS and in severe asthma when it is added to high doses of ICS plus LABA, as well as in adolescents. Tiotropium is cost effective and its benefits are not restricted to particular phenotypes, making it a useful addition to the therapeutic options recommended by the Global Initiative for Asthma (GINA) for people with poorly controlled asthma at steps 4 & 5.

Efficacy and safety of ipratropium bromide/albuterol compared with albuterol in patients with moderate-to-severe asthma: a randomized controlled trial

BACKGROUND

Many patients with asthma require frequent rescue medication for acute symptoms despite appropriate controller therapies. Thus, determining the most effective relief regimen is important in the management of more severe asthma. This study's objective was to evaluate whether ipratropium bromide/albuterol metered-dose inhaler (CVT-MDI) provides more effective acute relief of bronchospasm in moderate-to-severe asthma than albuterol hydrofluoroalkaline (ALB-HFA) alone after 4 weeks.

METHODS

In this double-blind, crossover study, patients who had been diagnosed with asthma for ≥1 year were randomized to two sequences of study medication "as needed" for symptom relief (1-7 day washout before second 4-week treatment period): CVT-MDI/ALB-HFA or ALB-HFA/CVT-MDI. On days 1 and 29 of each sequence, 6-hour serial spirometry was performed after administration of the study drug. Co-primary endpoints were FEV1 area under the curve (AUC0-6) and peak (post-dose) forced expiratory volume in 1 s (FEV1) response (change from test day baseline) after 4 weeks. The effects of "as needed" treatment with ALB-HFA/CVT-MDI were analyzed using mixed effect model repeated measures (MMRM).

RESULTS

A total of 226 patients, ≥18 years old, with inadequately controlled, moderate-to-severe asthma were randomized. The study met both co-primary endpoints demonstrating a statistically significant treatment benefit of CVT-MDI versus ALB-HFA. FEV1 AUC0-6h response was 167 ml for ALB-HFA, 252 ml for CVT-MDI (p <0.0001); peak FEV1 response was 357 ml for ALB-HFA, 434 ml for CVT-MDI (p <0.0001). Adverse events were comparable across groups.

CONCLUSIONS

CVT-MDI significantly improved acute bronchodilation over ALB-HFA alone after 4 weeks of "as-needed" use for symptom relief, with a similar safety profile. This suggests additive bronchodilator effects of β2-agonist and anticholinergic treatment in moderate-to-severe, symptomatic asthma.

TRIAL REGISTRATION

ClinicalTrials.gov No.: NCT00818454 ; Registered November 16, 2009.

What is the role of tiotropium in asthma?: a systematic review with meta-analysis

BACKGROUND

The role of tiotropium for the treatment of asthma has not yet been clearly defined. The aim of this systematic review was to assess the efficacy and safety of tiotropium in patients with asthma.

METHODS

Randomized placebo-controlled trials were included. Primary outcomes were peak and trough FEV1 and morning and evening peak expiratory flow (PEF).

RESULTS

Thirteen studies (4,966 patients) were included. Three different therapeutic protocols were identified. Tiotropium as an add-on to inhaled corticosteroids (ICSs) showed statistically and clinically significant increases in PEF (22-24 L/min) and FEV1 (140-150 mL). Additionally, tiotropium decreased the rate of exacerbations (number needed to treat for benefit [NNTB], 36) and improved asthma control. The use of tiotropium in patients poorly controlled despite the use of medium to high doses of ICS was not inferior to salmeterol. Finally, the use of tiotropium as an add-on to ICS/salmeterol combination increased pulmonary function to a clinically significant magnitude, reduced asthma exacerbations (relative risk, 0.70; 95% CI, 0.53-0.94; P < .02; I2 = 0%; NNTB, 17), and improved asthma control compared with ICS/salmeterol. Tiotropium was well tolerated, and no potential safety signals were observed.

CONCLUSIONS

Tiotropium resulted noninferiorly to salmeterol and superiorly to placebo in patients with moderate to severe asthma who were not adequately controlled by ICS or ICS/salmeterol. Major benefits were concentrated in the increase in lung function and in the case of patients with severe asthma, in the reduction of exacerbations.

Anticholinergics/antimuscarinic drugs in asthma

Anticholinergic alkaloids have been used for thousands of years for the relief of bronchoconstriction and other respiratory symptoms, and their use in the treatment of chronic obstructive pulmonary disease is well established. Acetylcholine, acting through muscarinic receptor (M) receptor, modulates multiple physiologic functions pertinent to asthma including airway muscle tone, mucus gland secretion, and various parameters of inflammation and remodeling. In addition, activation of M receptors may inhibit beta2 adrenoreceptor. These observations offer the rationale for the use of M receptors antagonists in the treatment of asthma. Short-acting antimuscarinic agents may be effective alone or in combination with short-acting beta agonists for the relief of acute symptoms. Long-acting antimuscarinic agents have emerged as potentially useful in the long-term treatment of difficult-to-control asthma. This review will analyze the mechanisms of action and therapeutic role of antimuscarinic agents on asthma including current guidelines regarding antimuscarinic drugs, recent studies in asthma, special populations to consider, and possible predictors of response.

Is there a rationale and role for long-acting anticholinergic bronchodilators in asthma?

Despite current guidelines and the range of available treatments, over a half of patients with asthma continue to suffer from poor symptomatic control and remain at risk of future worsening. Although a number of non-pharmacological measures are crucial for good clinical management of asthma, new therapeutic controller medications will have a role in the future management of the disease. Several long-acting anticholinergic bronchodilators are under investigation or are available for the treatment of respiratory diseases, including tiotropium bromide, aclidinium bromide, glycopyrronium bromide, glycopyrrolate and umeclidinium bromide, although none is yet licensed for the treatment of asthma. A recent Phase III investigation demonstrated that the once-daily long-acting anticholinergic bronchodilator tiotropium bromide improves lung function and reduces the risk of exacerbation in patients with symptomatic asthma, despite the use of inhaled corticosteroids (ICS) and long-acting β₂-agonists (LABAs). This has prompted the question of what the rationale is for long-acting anticholinergic bronchodilators in asthma. Bronchial smooth muscle contraction is the primary cause of reversible airway narrowing in asthma, and the baseline level of contraction is predominantly set by the level of ‘cholinergic tone’. Patients with asthma have increased bronchial smooth muscle tone and mucus hypersecretion, possibly as a result of elevated cholinergic activity, which anticholinergic compounds are known to reduce. Further, anticholinergic compounds may also have anti-inflammatory properties. Thus, evidence suggests that long-acting anticholinergic bronchodilators might offer benefits for the maintenance of asthma control, such as in patients failing to gain control on ICS and a LABA, or those with frequent exacerbations.

Comparative effectiveness of long term drug treatment strategies to prevent asthma exacerbations: network meta-analysis

OBJECTIVE

To determine the comparative effectiveness and safety of current maintenance strategies in preventing exacerbations of asthma.

DESIGN

Systematic review and network meta-analysis using Bayesian statistics.

DATA SOURCES

Cochrane systematic reviews on chronic asthma, complemented by an updated search when appropriate. ELIGIBILITY CRITERIA TRIALS OF Adults with asthma randomised to maintenance treatments of at least 24 weeks duration and that reported on asthma exacerbations in full text. Low dose inhaled corticosteroid treatment was the comparator strategy. The primary effectiveness outcome was the rate of severe exacerbations. The secondary outcome was the composite of moderate or severe exacerbations. The rate of withdrawal was analysed as a safety outcome.

RESULTS

64 trials with 59,622 patient years of follow-up comparing 15 strategies and placebo were included. For prevention of severe exacerbations, combined inhaled corticosteroids and long acting β agonists as maintenance and reliever treatment and combined inhaled corticosteroids and long acting β agonists in a fixed daily dose performed equally well and were ranked first for effectiveness. The rate ratios compared with low dose inhaled corticosteroids were 0.44 (95% credible interval 0.29 to 0.66) and 0.51 (0.35 to 0.77), respectively. Other combined strategies were not superior to inhaled corticosteroids and all single drug treatments were inferior to single low dose inhaled corticosteroids. Safety was best for conventional best (guideline based) practice and combined maintenance and reliever therapy.

CONCLUSIONS

Strategies with combined inhaled corticosteroids and long acting β agonists are most effective and safe in preventing severe exacerbations of asthma, although some heterogeneity was observed in this network meta-analysis of full text reports.

Emerging role of long acting muscarinic antagonists for asthma

Acetlycholine is involved in the control of airway smooth muscle constriction and in recruitment of inflammatory cells via neuronal and paracrine effects on muscarinic type 3 receptors. Long acting muscarinic antagonists (LAMA) are well established in guidelines for COPD but are not currently licensed for use in asthma. There are emerging data from key clinical trials to show that LAMA may confer bronchodilator effects and improved control when used in addition to inhaled corticosteroid (ICS) alone or in conjunction with long acting β-adrenoceptor agonists (LABA). Further studies in persistent asthmatic patients are required to evaluate ICS sparing effects of LAMA looking particularly at airway hyper-responsiveness and surrogate inflammatory markers, in addition to evaluation of possible synergy between LAMA and LABA when given together. Future possible development of combination inhalers comprising ICS/LAMA or ICS/LAMA/LABA will require long term studies looking at asthma control and exacerbations in both adult and paediatric patients.

The asthma-chronic obstructive pulmonary disease overlap syndrome: pharmacotherapeutic considerations

Asthma-chronic obstructive pulmonary disease (COPD) overlap syndrome (ACOS) is a commonly encountered yet loosely defined clinical entity. ACOS accounts for approximately 15-25% of the obstructive airway diseases and patients experience worse outcomes compared with asthma or COPD alone. Patients with ACOS have the combined risk factors of smoking and atopy, are generally younger than patients with COPD and experience acute exacerbations with higher frequency and greater severity than lone COPD. Pharmacotherapeutic considerations require an integrated approach, first to identify the relevant clinical phenotype(s), then to determine the best available therapy. The authors discuss the array of existing and emerging classes of drugs that could benefit those with ACOS and share their therapeutic approach. A consensus international definition of ACOS is needed to design prospective, randomized clinical trials to evaluate specific drug interventions on important outcomes such as lung function, acute exacerbations, quality of life and mortality.

The role of tiotropium in the management of asthma

Asthma is a chronic respiratory disease characterized by reversible airway obstruction that is secondary to an allergic inflammation and excessive smooth muscle contraction. Cholinergic signals were known to contribute significantly to the pathophysiology of asthma. However, the use of anti-cholinergic agents in asthma has been justified only in acute asthma exacerbations, until tiotropium bromide, a long-acting anti-cholinergic agent was introduced. Recent reports showing a promising role of tiotropium in the treatment of asthma have aroused interest of the use of anti-cholinergic agent for the management of asthma. This report describes pharmacological characteristics, potential effects on inflammatory cells, and the current status of tiotropium in the treatment of asthma.

An integrative review of systematic reviews related to the management of breathlessness in respiratory illnesses

BACKGROUND

Breathlessness is a debilitating and distressing symptom in a wide variety of diseases and still a difficult symptom to manage. An integrative review of systematic reviews of non-pharmacological and pharmacological interventions for breathlessness in non-malignant disease was undertaken to identify the current state of clinical understanding of the management of breathlessness and highlight promising interventions that merit further investigation.

METHODS

Systematic reviews were identified via electronic databases between July 2007 and September 2009. Reviews were included within the study if they reported research on adult participants using either a measure of breathlessness or some other measure of respiratory symptoms.

RESULTS

In total 219 systematic reviews were identified and 153 included within the final review, of these 59 addressed non-pharmacological interventions and 94 addressed pharmacological interventions. The reviews covered in excess of 2000 trials. The majority of systematic reviews were conducted on interventions for asthma and COPD, and mainly focussed upon a small number of pharmacological interventions such as corticosteroids and bronchodilators, including beta-agonists. In contrast, other conditions involving breathlessness have received little or no attention and studies continue to focus upon pharmacological approaches. Moreover, although there are a number of non-pharmacological studies that have shown some promise, particularly for COPD, their conclusions are limited by a lack of good quality evidence from RCTs, small sample sizes and limited replication.

CONCLUSIONS

More research should focus in the future on the management of breathlessness in respiratory diseases other than asthma and COPD. In addition, pharmacological treatments do not completely manage breathlessness and have an added burden of side effects. It is therefore important to focus more research on promising non-pharmacological interventions.

Tiotropium bromide step-up therapy for adults with uncontrolled asthma

BACKGROUND

Long-acting beta-agonist (LABA) therapy improves symptoms in patients whose asthma is poorly controlled by an inhaled glucocorticoid alone. Alternative treatments for adults with uncontrolled asthma are needed.

METHODS

In a three-way, double-blind, triple-dummy crossover trial involving 210 patients with asthma, we evaluated the addition of tiotropium bromide (a long-acting anticholinergic agent approved for the treatment of chronic obstructive pulmonary disease but not asthma) to an inhaled glucocorticoid, as compared with a doubling of the dose of the inhaled glucocorticoid (primary superiority comparison) or the addition of the LABA salmeterol (secondary noninferiority comparison).

RESULTS

The use of tiotropium resulted in a superior primary outcome, as compared with a doubling of the dose of an inhaled glucocorticoid, as assessed by measuring the morning peak expiratory flow (PEF), with a mean difference of 25.8 liters per minute (P<0.001) and superiority in most secondary outcomes, including evening PEF, with a difference of 35.3 liters per minute (P<0.001); the proportion of asthma-control days, with a difference of 0.079 (P=0.01); the forced expiratory volume in 1 second (FEV1) before bronchodilation, with a difference of 0.10 liters (P=0.004); and daily symptom scores, with a difference of -0.11 points (P<0.001). The addition of tiotropium was also noninferior to the addition of salmeterol for all assessed outcomes and increased the prebronchodilator FEV1 more than did salmeterol, with a difference of 0.11 liters (P=0.003).

CONCLUSIONS

When added to an inhaled glucocorticoid, tiotropium improved symptoms and lung function in patients with inadequately controlled asthma. Its effects appeared to be equivalent to those with the addition of salmeterol. (Funded by the National Heart, Lung, and Blood Institute; ClinicalTrials.gov number, NCT00565266.).

Management of chronic obstructive pulmonary disease: moving beyond the asthma algorithm

For many years, chronic obstructive pulmonary disease (COPD) was considered a disease of fixed airflow obstruction for which there was no good treatment. Out of desperation and frustration, health care providers extrapolated from asthma to COPD, and standard asthma therapy was adopted without evidence for efficacy. In recent years, we have gained a better understanding of the pathophysiologic differences between asthma and COPD, and prospective controlled trials have provided a rationale for therapy. Smoking cessation is critically important, both as primary prevention and as an effective way to slow the decrease in lung function in patients with established disease. beta(2)-Adrenergic and anticholinergic agonists improve lung function and relieve symptoms in most patients. Tiotropium improves exercise tolerance and quality of life and reduces exacerbations and hospitalizations. The increase in lung function seen with tiotropium is sustained with continued use over at least 3 to 4 years. Inhaled corticosteroids decrease exacerbations and improve quality of life, and their effect seems greatest in patients with lower lung function and in exacerbation-prone patients. There is no evidence that inhaled corticosteroids alone affect mortality, despite the reduction in exacerbations and increased risk of pneumonia. In some patient populations, inhaled fluticasone, salmeterol, or the combination might slow the rate of loss of lung function. Rather than reflexively using effective asthma therapy in the patient with COPD, current and future therapy for COPD is increasingly evidence based and targeted to specific inflammatory pathways that are important in patients with COPD.

Anticholinergic treatment in airways diseases

The prevalence of chronic airways diseases such as chronic obstructive pulmonary disease and asthma is increasing. They lead to symptoms such as a cough and shortness of breath, partially through bronchoconstriction. Inhaled anticholinergics are one of a number of treatments designed to treat bronchoconstriction in airways disease. Both short-acting and long-acting agents are now available and this review highlights their efficacy and adverse event profile in chronic airways diseases.

Asthma in US seniors: part 2. Treatment. Seeing through the glass darkly

BACKGROUND

We sought to identify the best evidence for treatment of asthmatic patients aged 65 years or more.

METHODS

We used computer-assisted searches to identify randomized, controlled trials for asthma in the elderly that were published in English between 1950 and 2008.

RESULTS

Small trials of an inhaled corticosteroid versus a leukotriene antagonist and an oral beta(2)-agonist versus placebo compose the controlled trial data on asthma therapy in seniors. Epidemiologic evidence suggests that the side effects of corticosteroids and beta-agonists may be more common in the elderly than in younger populations.

CONCLUSION

Seniors with asthma or comorbid conditions that are common in the elderly have been systematically excluded from asthma treatment trials. There is no compelling evidence to demonstrate the superiority of any pharmacologic therapy in these asthmatic patients. Evaluation of response to asthma treatment in clinical trials remains primarily symptom-based when symptoms have been shown to underestimate the severity of disease in seniors.

Potential adverse effects of bronchodilators in the treatment of airways obstruction in older people: recommendations for prescribing

Asthma and chronic obstructive pulmonary disease (COPD) are common disorders that are associated with increasing morbidity and mortality in older people. Bronchodilators are used widely in patients with these conditions, but even when used in inhaled form can have systemic as well as local effects. Older people experience more adverse drug effects because of pharmacodynamic and pharmacokinetic changes and particularly drug-drug and drug-disease interactions. Cardiovascular disease is common in older people and beta-adrenoceptor agonists (beta-agonists) have inotropic and chronotropic effects that can increase arrhythmias and cardiomyopathy. They can also worsen or induce myocardial ischaemia and cause electrolyte disturbances that contribute to arrhythmias. Tremor is a well known distressing adverse effect of beta-agonist administration. Long-term beta-agonist use can be associated with tolerance, poor disease control, sudden life-threatening exacerbations and asthma-related deaths. Functional beta2-adrenoceptors are present in osteoblasts, and chronic use of beta-agonists has been implicated in osteoporosis. Inhaled anticholinergics are usually well tolerated but may cause dry mouth, which can be troublesome in older people. Pupillary dilatation, blurred vision and acute glaucoma can occur from escape of droplets from loosely fitting nebulizer masks. Although ECG changes have not been seen in randomized controlled trials of long-acting inhaled anticholinergics, supraventricular tachycardias have been observed in a 5-year randomized controlled trial of ipratropium bromide. Paradoxical bronchoconstriction can occur with inhaled anticholinergics as well as with beta-agonists, but tolerance has not been reported with anticholinergics. Anticholinergic drugs also cause central effects, most notably impairment of cognitive function, and these effects have been noted with inhaled agents. Use of theophylline is limited by its adverse effects, which range from commonly occurring gastrointestinal symptoms to palpitations, arrhythmias and reports of myocardial infarction. Seizures have been reported, but are rare. Theophylline is metabolized primarily by the liver, and commonly interacts with other medications. Its concentration in plasma should be monitored closely, especially in older people. Although many clinical trials have been conducted on bronchodilators in obstructive airways disease, the results of these clinical trials need to be interpreted with caution as older people are often under-represented and subjects with co-morbidities actively excluded from these trials.

Severe asthma in adults: what are the important questions?

The term severe refractory asthma (SRA) in adults applies to patients who remain difficult to control despite extensive re-evaluation of diagnosis and management following an observational period of at least 6 months by a specialist. Factors that influence asthma control should be recognized and adequately addressed prior to confirming the diagnosis of SRA. This report presents statements according to the literature defining SRA in order address the important questions. Phenotyping SRA will improve our understanding of mechanisms, natural history, and prognosis. Female gender, obesity, and smoking are associated with SRA. Atopy is less frequent in SRA, but occupational sensitizers are common inducers of new-onset SRA. Viruses contribute to severe exacerbations and can persist in the airways for long periods. Inflammatory cells are in the airways of the majority of patients with SRA and persist despite steroid therapy. The T(H)2 immune process alone is inadequate to explain SRA. Reduced responsiveness to corticosteroids is common, and epithelial cell and smooth muscle abnormalities are found, contributing to airway narrowing. Large and small airway wall thickening is observed, but parenchymal abnormalities may influence airway limitation. Inhaled corticosteroids and bronchodilators are the mainstay of treatment, but patients with SRA remain uncontrolled, indicating a need for new therapies.

Atropine pretreatment enhances airway hyperreactivity in antigen-challenged guinea pigs through an eosinophil-dependent mechanism

Airway hyperreactivity in antigen-challenged animals is mediated by eosinophil major basic protein (MBP) that blocks inhibitory M(2) muscarinic receptors on parasympathetic nerves, increasing acetylcholine release onto M(3) muscarinic receptors on airway smooth muscle. Acutely, anticholinergics block hyperreactivity in antigen-challenged animals and reverse asthma exacerbations in the human, but are less effective in chronic asthma. We tested whether atropine, given before antigen challenge, affected hyperreactivity, M(2) receptor function, eosinophil accumulation, and activation. Sensitized guinea pigs received atropine (1 mg/kg ip) 1 h before challenge and 6 h later. Twenty-four hours after challenge, animals were anesthetized, vagotomized, paralyzed, and ventilated. Airway reactivity to electrical stimulation of the vagi and to intravenous acetylcholine was not altered by atropine pretreatment in nonsensitized animals, indicating that atropine was no longer blocking postjunctional muscarinic receptors. Antigen challenge induced airway hyperreactivity to vagal stimulation that was significantly potentiated by atropine pretreatment. Bronchoconstriction induced by acetylcholine was not changed by antigen challenge or by atropine pretreatment. M(2) receptor function was lost in challenged animals but protected by atropine pretreatment. Eosinophils in bronchoalveolar lavage and within airway tissues were significantly increased by challenge but significantly reduced by atropine pretreatment. However, extracellular MBP in challenged airways was significantly increased by atropine pretreatment, which may account for reduced eosinophils. Depleting eosinophils with antibody to IL-5 before challenge prevented hyperreactivity and significantly reduced MBP in airways of atropine-pretreated animals. Thus atropine pretreatment potentiated airway hyperreactivity by increasing eosinophil activation and degranulation. These data suggest that anticholinergics enhance eosinophil interactions with airway nerves.

The mechanisms, diagnosis, and management of severe asthma in adults

There has been a recent increase in the prevalence of asthma worldwide; however, the 5-10% of patients with severe disease account for a substantial proportion of the health costs. Although most asthma cases can be satisfactorily managed with a combination of anti-inflammatory drugs and bronchodilators, patients who remain symptomatic despite maximum combination treatment represent a heterogeneous group consisting of those who are under-treated or non-adherent with their prescribed medication. After excluding under-treatment and poor compliance, corticosteroid refractory asthma can be identified as a subphenotype characterised by a heightened neutrophilic airway inflammatory response in the presence or absence of eosinophils, with evidence of increased tissue injury and remodelling. Although a wide range of environmental factors such as allergens, smoking, air pollution, infection, hormones, and specific drugs can contribute to this phenotype, other features associated with changes in the airway inflammatory response should be taken into account. Aberrant communication between an injured airway epithelium and underlying mesenchyme contributes to disease chronicity and refractoriness to corticosteroids. The importance of identifying underlying causative factors and the recent introduction of novel therapeutic approaches, including the targeting of immunoglobulin E and tumour necrosis factor alpha with biological agents, emphasise the need for careful phenotyping of patients with severe disease to target improved management of the individual patient's needs.

Overcoming gaps in the management of asthma in older patients: new insights

Asthma is under-recognised and undertreated in older populations. This is not surprising, given that one-third of older people experience significant breathlessness. The differential diagnosis commonly includes asthma, chronic obstructive pulmonary disease (COPD), heart failure, malignancy, aspiration and infections. Because symptoms and signs of several cardiorespiratory diseases are nonspecific in older people and diseases commonly co-exist, investigations are important. A simple strategy for the investigation of breathlessness in older people should include a full blood count, chest radiograph, ECG, peak flow diary and/or spirometry with reversibility as a minimum. If there are major abnormalities on the ECG, an echocardiogram should also be performed. Diurnal variability in peak flow readings >or=20% or >or=15% reversibility in forced expiratory volume in 1 second, spontaneously or with treatment, support a diagnosis of asthma. Distinguishing asthma from COPD is important to allow appropriate management of disease based on aetiology, accurate prediction of treatment response, correct prognosis and appropriate management of the chest condition and co-morbidities. The two conditions are usually readily differentiated by clinical features, particularly age at onset, variability of symptoms and nocturnal symptoms in asthma, supported by the results of reversibility testing. Full lung function tests may not necessarily help in differentiating the two entities, although gas transfer factor is characteristically reduced in COPD and usually normal or high in asthma. Methacholine challenge tests previously mainly used in research are now also used widely and safely to confirm asthma in clinical settings. Interest in exhaled nitric oxide as a biomarker of airways inflammation is increasing as a noninvasive tool in the diagnosis and monitoring of asthma. Regular inhaled corticosteroids (ICS) are the mainstay of treatment of asthma. Even in mild disease in older adults, regular preventive treatment should be considered, given the poor perception of bronchoconstriction by older asthmatic patients. If symptoms persist despite ICS, addition of long-acting beta(2)-adrenoceptor agonists (LABA) should be considered. Addition of LABA to ICS improves asthma control and allows reduction in ICS dose. However, older people have been grossly under-represented in trials of LABA, many trials having excluded those >or=65 years of age. On meta-analysis, beta(2)-adrenoceptor agonists (both short acting and long acting) are associated with increased cardiovascular mortality and morbidity in asthma and COPD. While the evidence for excess cardiovascular mortality is stronger for short-acting beta(2)-adrenoceptor agonists, it would be prudent to exercise particular care in using beta(2)-adrenoceptor agonists (long acting and short acting) in those at risk of adverse cardiovascular outcomes, including older people. Regular review of cardiovascular status (and monitoring of serum potassium concentration) in patients taking beta(2)-adrenoceptor agonists is crucial. The response to LABA should be carefully monitored and alternative 'add-on' therapy such as leukotriene receptor antagonists (LRA) should be considered. LRA have fewer adverse effects and in individual cases may be more effective and appropriate than LABA. Long-term trials evaluating beta(2)-adrenoceptor agonists and other bronchodilator strategies are needed particularly in the elderly and in patients with cardiovascular co-morbidities. There is no evidence that addition of anticholinergics improves control of asthma further, although the role of long-acting anticholinergics in the prevention of disease progression is currently being researched. Older patients need to be taught good inhaler technique to improve delivery of medications to lungs, minimise adverse effects and reduce the need for oral corticosteroids. Nurse-led education programmes that include a written asthma self-management plan have the potential to improve outcomes.