Long-acting beta2-agonists in asthma: an overview of Cochrane systematic reviews

Multidisciplinary Development and Initial Validation of a Clinical Knowledge Base on Chronic Respiratory Diseases for mHealth Decision Support Systems

Most mobile health (mHealth) decision support systems currently available for chronic obstructive respiratory diseases (CORDs) are not supported by clinical evidence or lack clinical validation. The development of the knowledge base that will feed the clinical decision support system is a crucial step that involves the collection and systematization of clinical knowledge from relevant scientific sources and its representation in a human-understandable and computer-interpretable way. This work describes the development and initial validation of a clinical knowledge base that can be integrated into mHealth decision support systems developed for patients with CORDs. A multidisciplinary team of health care professionals with clinical experience in respiratory diseases, together with data science and IT professionals, defined a new framework that can be used in other evidence-based systems. The knowledge base development began with a thorough review of the relevant scientific sources (eg, disease guidelines) to identify the recommendations to be implemented in the decision support system based on a consensus process. Recommendations were selected according to predefined inclusion criteria: (1) applicable to individuals with CORDs or to prevent CORDs, (2) directed toward patient self-management, (3) targeting adults, and (4) within the scope of the knowledge domains and subdomains defined. Then, the selected recommendations were prioritized according to (1) a harmonized level of evidence (reconciled from different sources); (2) the scope of the source document (international was preferred); (3) the entity that issued the source document; (4) the operability of the recommendation; and (5) health care professionals' perceptions of the relevance, potential impact, and reach of the recommendation. A total of 358 recommendations were selected. Next, the variables required to trigger those recommendations were defined (n=116) and operationalized into logical rules using Boolean logical operators (n=405). Finally, the knowledge base was implemented in an intelligent individualized coaching component and pretested with an asthma use case. Initial validation of the knowledge base was conducted internally using data from a population-based observational study of individuals with or without asthma or rhinitis. External validation of the appropriateness of the recommendations with the highest priority level was conducted independently by 4 physicians. In addition, a strategy for knowledge base updates, including an easy-to-use rules editor, was defined. Using this process, based on consensus and iterative improvement, we developed and conducted preliminary validation of a clinical knowledge base for CORDs that translates disease guidelines into personalized patient recommendations. The knowledge base can be used as part of mHealth decision support systems. This process could be replicated in other clinical areas.

The Association Between Beliefs and Adherence to Inhaled Controller Medication Among Older Adults with Asthma: A Cross-Sectional Study in Primary Care

BACKGROUND

While illness perceptions and medication beliefs have been shown to be associated with inhaled corticosteroid (ICS) adherence in younger adults with asthma, their impact on older adults is less understood. This study aimed to determine the prevalence of ICS adherence among older Asian adults and to assess the association between ICS adherence, illness perceptions and medication beliefs.

METHODS

A questionnaire survey on older multi-ethnic Asian patients, aged ≥60 years, with physician-diagnosed asthma, was conducted in two Singapore public primary care clinics. The scores of the Medication Adherence Report Scale for asthma (MARS) were computed to determine the adherence to ICS alone or in combination with LABA. Illness perceptions and medication beliefs were assessed by the scores from the Brief-Illness Perception Questionnaire (B-IPQ) and Beliefs about Medications Questionnaire (BMQ), respectively. Logistic regression analyses were used to identify factors associated with ICS adherence.

RESULTS

Analyses of 323 participants (57% males; Chinese 73.7%, Malay 12.7%, Indian 12.4%; mean age 71.5 years) showed that 40.9% of them had good adherence to ICS (mean MARS score≥4.5). Good adherence to ICS was associated with perception of asthma as a chronic illness (OR=1.22; 95% CI=1.10-1.35; p<0.001), belief of ICS as an essential medication (2.67; 1.76-4.06; p<0.001) and fewer concerns about its use (0.39; 0.26-0.60; p<0.001). Patients on combined ICS-LABA therapy had higher adherence (2.50; 1.41-4.44; p=0.02) than those on ICS monotherapy.

CONCLUSION

Four in ten older patients with asthma were adherent to ICS. Perception of medication necessity, chronicity of illness, concerns and use of ICS-LABA medication were associated with adherence.

Dual regulation of β2-adrenoceptor messenger RNA expression in human lung fibroblasts by β2-cAMP signaling; delayed upregulated inhibitors oppose a rapid in onset, direct stimulation of gene expression

Based on their bronchodilatory effect, β2-adrenoceptor agonists constitute essential elements in the treatment of bronchial asthma and COPD. As treatment with β2-adrenoceptor agonists has been associated with worsening of airway hyper-reactivity, possibly because of loss of β-adrenoceptor function, molecular mechanism of the regulation of β2-adrenoceptor expression were studied. MRC-5 human lung fibroblasts were cultured in absence or presence of test substances followed by β2-adrenoceptor messenger RNA (mRNA) determination by qPCR. After inhibition of mRNA synthesis by actinomycin D, β2-adrenoceptor mRNA decreased with a half-life of 23 min, whereas inhibition of protein synthesis by cycloheximide caused an about 5- and 6-fold increase within 1.5 and 4 h, respectively. β2-Adrenoceptor mRNA was increased by about 100 % after 1 h exposure to formoterol or olodaterol but decreased by about 60 % after 4 h agonist exposure. Both effects of β2-adrenoceptor agonists were mimicked by forskolin, a direct activator of adenylyl cyclase and cholera toxin, which stimulates adenylyl cyclase by permanent activation of Gs. β2-Adrenoceptor agonist-induced upregulation of β2-adrenoceptor mRNA was blocked by the β2-adrenoceptor antagonist ICI 118551 and prevented by actinomycin D, but not by cycloheximide. Moreover, in presence of cycloheximide, β2-adrenoceptor agonist-induced reduction in β2-adrenoceptor mRNA was converted into stimulation, resulting in a more than 10-fold increase. In conclusion, expression of β2-adrenoceptors in human lung fibroblasts is highly regulated at transcriptional level. The β2-adrenoceptor gene is under strong inhibitory control of short-living suppressor proteins. β2-Adrenoceptor activation induces via adenylyl cyclase - cyclic adenosine monophosphate (cAMP) signaling a rapid in onset direct stimulation of the β2-adrenoceptor gene transcription, an effect opposed by a delayed upregulation of inhibitory factors.

The β2-subtype of adrenoceptors mediates inhibition of pro-fibrotic events in human lung fibroblasts

Fibrosis is part of airway remodelling observed in bronchial asthma and COPD. Pro-fibrotic activity of lung fibroblasts may be suppressed by β-adrenoceptor activation. We aimed, first, to characterise the expression pattern of β-adrenoceptor subtypes in human lung fibroblasts and, second, to probe β-adrenoceptor signalling with an emphasis on anti-fibrotic actions. Using reverse transcription PCR, messenger RNA (mRNA) encoding β(2)-adrenoceptors was detected in MRC-5, HEL-299 and primary human lung fibroblasts, whereas transcripts for β(1)- and β(3)-adrenoceptors were not found. Real-time measurement of dynamic mass redistribution in MRC-5 cells revealed β-agonist-induced G(s)-signalling. Proliferation of MRC-5 cells (determined by [(3)H]-thymidine incorporation) was significantly inhibited by β-agonists including the β(2)-selective agonist formoterol (-logIC(50), 10.2) and olodaterol (-logIC(50), 10.6). Formoterol's effect was insensitive to β(1)-antagonism (GCP 20712, 3 μM), but sensitive to β(2)-antagonism (ICI 118,551; apparent, pA (2), 9.6). Collagen synthesis in MRC-5 cells (determined by [(3)H]-proline incorporation) was inhibited by β-agonists including formoterol (-logIC(50), 10.0) and olodaterol (-logIC(50), 10.3) in a β(2)-blocker-sensitive manner. α-Smooth muscle actin, a marker of myo-fibroblast differentiation, was down-regulated at the mRNA and the protein level by about 50% following 24 and 48 h exposure to 1 nM formoterol, a maximally active concentration. In conclusion, human lung fibroblasts exclusively express β(2)-adrenoceptors and these mediate inhibition of various markers of pro-fibrotic cellular activity. Under clinical conditions, anti-fibrotic actions may accompany the therapeutic effect of long-term β(2)-agonist treatment of bronchial asthma and COPD.

Airway smooth muscle modulation and airway hyper-responsiveness in asthma: new cellular and molecular paradigms

There is growing evidence indicating the existence of a causal relationship between abnormal airway smooth muscle (ASM) function and airway hyper-responsiveness, a poorly understood feature of asthma that can be defined as an excessive bronchospastic response. In recent years, there has been a veritable explosion of articles suggesting that ASM exposed to proasthmatic cytokines can elicit a hyper-responsive state to contractile G-protein-coupled receptor (GPCR) agonists. Aberrant airway responsiveness could result from abnormal calcium signaling, with changes occurring at various levels of GPCR-associated signal transduction. This review presents the latest observations describing novel mechanistic models that could explain the involvement of ASM in airway hyper-responsiveness. This review will discuss the role of ASM in beta(2)-agonist-mediated bronchial hyper-responsiveness and the clinical significance of cell-cell contact between ASM and mast cells recently described to be intimately infiltrated within the ASM tissues in asthmatic patients. The possibility that allergens could trigger airway hyper-responsiveness by directly acting on ASM via activation of immunoglobulin E receptors, FcepsilonRI and FCepsilonRII will also be discussed. These important findings further support the notion that targeting ASM could offer new treatment for many features of asthma, including airway hyper-responsiveness. Future therapeutic intervention includes: the prevention of ASM-inflammatory cell physical and/or functional interaction, the inhibition of Immunoglobulin E receptor-dependent signal transduction, and the abrogation of cytokine-dependent pathways that modulate receptor-associated calcium metabolism.

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.

Safety of long-acting beta2-agonists in the treatment of asthma

Several studies suggested an association between the regular use of beta2-agonists and asthma deaths. Whether this association represents adverse effects of beta -agonist use or is entirely due to disease severity is a matter of ongoing debate. Previous literature indicates that confounding by poor asthma control may explain the apparent deleterious effects of inhaled beta2-agonists. Tolerance to nonbronchodilator effects of beta2-agonists may account for the increase in reactivity to indirect bronchoconstrictor challenges and explain why some studies have demonstrated enhanced bronchoconstriction in patients with asthma after regular beta 2-agonist therapy. Nonetheless, the salmeterol multi-centre asthma research trial (SMART) found more asthma deaths (13 vs 3) and life-threatening asthma events (37 vs 22) in the salmeterol-treated asthmatic patients, although it was documented that among African-Americans, 5 times as many deaths and near-deaths from asthma occurred in those given salmeterol than in those given placebo, and among patients with asthma not using an inhaled corticosteroid (ICS) as a preventive (controller) medication, again more deaths and near-deaths from asthma occurred in those given salmeterol than in those given placebo. Only 38% of the African-Americans who participated in the study used an ICS. As a result of the findings from the SMART, FDA issued a public health advisory to highlight that long-acting beta2-agonists (LABAs) should not be the first medicine used to treat asthma. LABAs should be added to the asthma treatment plan only if other medicines, including the use of low-or-medium dose ICSs, do not control asthma. However, despite all of the concerns raised by the SMART, inhaled beta2-agonists remain the most effective bronchodilators available for the immediate relief of asthma symptoms and, as such, remain an important component of asthma management. Obviously, there are concerns about LABA treatment as monotherapy for asthma. Patients with asthma should be initiated and maintained on sufficiently high doses of ICSs and only patients whose asthma cannot be controlled should receive additional LABAs on a regular basis.

Potential side effects in patients treated with inhaled corticosteroids and long-acting beta2-agonists

BACKGROUND

Long-acting-beta-agonists and inhaled corticosteroids are widely used in patients with obstructive lung disease. We determined the occurrence of potential side effects to inhaled steroids and long-acting-beta-agonists in an open post-marketing observational study.

METHODS

A total of 158 adult patients treated with long-acting-beta-agonists and inhaled steroids because of asthma or chronic obstructive lung disease were included prospectively in a cross-sectional study from September 2004 through august 2005. A subgroup of 31 patients with minimal disease were observed prospectively after treatment reduction. The frequency and intensity of potential side effects to long-acting-beta-agonists and inhaled corticosteroids were registered on a 10-point visual analogue scale.

RESULTS

A total of 131 (83%) reported potential side effects to inhaled steroids. The most frequent were sore (54%) and dry (52%) throat. A total of 114 (72%) patients reported potential side effects to long-acting-beta-agonists. The most frequent were muscle cramps (62%) and muscle twisting (39%). For 5/8 potential side effects their occurrence increased with increased individual dozing. In 31 patients the mean medication with steroids and long-acting-beta-agonists was reduced by 87% and 97.5%, respectively, with side effects reduced by 62% (p<0.001) to inhaled steroids and by 91% (p<0.001) to inhaled long-acting-beta-agonists.

CONCLUSIONS

Potential side effects in adult patients to inhaled corticosteroids and long-acting-beta-agonists are very common with increased frequency with increased dozing. Patients are largely unaware of the association. Patients should be better informed, and the results further support tailored dozing to minimum therapy.

Benefits of fixed-dose combination therapy with inhaled corticosteroids and long-acting bronchodilators as initial maintenance therapy in the management of asthma

BACKGROUND AND OBJECTIVE

Revised Australian guidelines for asthma management were released by the National Asthma Council (NAC) in 2006. One area where clinical opinion and trial data have changed recently concerns the place of fixed-dose combination (FDC) therapy with inhaled corticosteroid (ICS) and long-acting beta(2)-agonists as initial maintenance therapy.

METHODS

A systematic review of the literature commissioned by the NAC and undertaken by the University of Tasmania addressed several questions, including whether there was evidence for the use of FDC therapy as first-line asthma treatment in steroid-naïve patients.

RESULTS

Nineteen relevant studies were identified, from which 20 comparisons contributed to the analyses. The definition of steroid-naïve ranged from no ICS therapy over the preceding 1 month to no ICS therapy ever. FDC therapy was effective in subjects who were steroid-naïve and was more effective than an equivalent dose of ICS, irrespective of the definition of steroid-naïvety. Compared with ICS alone, FDC therapy increased mean FEV(1) by 140 mL, mean morning PEF by 21 L/min and mean evening PEF by 20 L/min. There was a mean increase of 9.8% in symptom-free days, associated with a greater reduction in rescue medication use of -0.12 puff/24 h. FDC therapy was not superior to ICS alone for prevention of withdrawals or exacerbations requiring systemic corticosteroids. Adverse events were similar for FDC therapy and ICS, whether ICS were administered at the same or an increased dose.

CONCLUSIONS

FDC therapy is effective as first-line treatment in steroid-naïve subjects and is superior to ICS alone for most outcomes, irrespective of the period of time since last exposure to ICS.

Novel long-acting bronchodilators for COPD and asthma

An important step in simplifying asthma and chronic obstructive pulmonary disease (COPD) management and improving adherence with prescribed therapy is to reduce the dose frequency to the minimum necessary to maintain disease control. Therefore, the incorporation of once-daily dose administration is an important strategy to improve adherence and is a regimen preferred by most patients, which may also lead to enhancement of compliance, and may have advantages leading to improved overall clinical outcomes. Once-daily beta2-agonists or ultra long-acting beta2-agonists (LABAs) such as carmoterol, indacaterol, GSK-159797, GSK-597901, GSK-159802, GSK-642444 and GSK-678007 are under development for the treatment of asthma and COPD. Also some new long-acting antimuscarinic agents (LAMAs) such as aclidinium, LAS-35201, GSK656398, GSK233705, NVA-237 (glycopyrrolate) and OrM3 are under development. In any case, the current opinion is that it will be advantageous to develop inhalers containing combination of several classes of long-acting bronchodilator drugs in an attempt to simplify treatment regimens as much as possible. Consequently, several options for once-daily dual-action ultra LABA+LAMA combination products are currently being evaluated. A different approach is to have a dimer molecule in which both pharmacologies are present (these molecules are known as M3 antagonist-beta2 agonist (MABA) bronchodilators). The advent of a successful MABA product will revolutionize the field and open the door for a new range of combination products.

Combined salmeterol/fluticasone propionate versus fluticasone propionate alone in mild asthma : a placebo-controlled comparison

BACKGROUND AND OBJECTIVE

Combined therapy with inhaled corticosteroids (ICSs) and long-acting beta(2)-adrenoceptor agonists (LABAs) is the recommended approach for the treatment of patients with asthma that is uncontrolled on ICSs alone. Additional studies are needed to assess the safety and efficacy of combination treatment with ICSs and LABAs in patients with mild asthma. The aim of this study was to compare the efficacy and tolerability of once-daily salmeterol/fluticasone propionate combination (SFC) with once-daily fluticasone propionate (FP) over a 12-week treatment period in patients with mild persistent asthma.

METHODS

This was a randomized, double-blind, placebo-controlled, parallel-group, multicentre study carried out in primary care or at a hospital outpatient department and included patients 12-79 years of age with mild persistent asthma (n = 458). After a 2-week run-in period, patients were randomized to receive SFC 50 microg/100 microg (n = 149), FP 100 microg (n = 154) or placebo (n = 155) once daily in the morning for 12 weeks. The primary efficacy endpoint was patient-recorded pre-dose mean morning peak expiratory flow (PEF). Other assessments included asthma symptom scores, use of rescue medication and investigator-recorded exacerbations. Lung function was measured and assessed during clinic visits.

RESULTS

For the primary efficacy endpoint of mean change in morning PEF, SFC achieved significantly greater increases from baseline than both placebo (difference in adjusted means 23 L/min; 95% CI 15.0, 30.3; p < 0.001) and FP (difference in adjusted means 14 L/min; 95% CI 6.3, 21.7; p < 0.001). Compared with those who received FP, patients in the SFC group demonstrated significantly greater improvements in mean evening PEF (95% CI 11.7, 28.1; p < 0.001), forced expiratory volume in 1 second (95% CI 0.093, 0.257; p < 0.001), forced expiratory flow between 25% and 75% of forced vital capacity (95% CI 0.242, 0.617; p < 0.001), the percentage of symptom-free days (95% CI 0.34, 0.87; p = 0.011), and the percentage of rescue medication-free days (95% CI 0.34, 0.90; p = 0.018). During weeks 5-12, 52% of patients in the SFC group achieved 'well controlled' asthma, compared with 42% and 26% of patients in the FP and placebo groups, respectively. Only one patient (receiving placebo) had a severe asthma exacerbation during the study; the frequency of adverse events was similar across the three treatment groups.

CONCLUSION

Once-daily SFC 50 microg/100 microg provided significantly greater improvements in lung function and in asthma symptoms than once-daily FP 100 microg alone in patients with mild persistent asthma. However, twice-daily treatment with either SFC or ICSs plus short acting beta(2)-adrenoceptor agonists could be required to achieve guideline-defined asthma control in some patients.

Pulmonary fibroblasts, an emerging target for anti-obstructive drugs

Fibrotic alterations are part of the airway re-modelling processes observed in asthma and chronic obstructive pulmonary disease. There is increasing evidence that in addition to acute bronchodilatory effects, classical anti-obstructive drugs such as muscarinic antagonists and beta-adrenoceptor agonists may also modulate long-term re-modelling processes. The present review aims to summarise muscarinic and beta-adrenergic effects on pulmonary fibroblasts. Recent experimental evidence demonstrated muscarinic stimulatory effects on pulmonary fibroblasts, and long-term blockade of these pro-fibrotic effects may contribute to the beneficial effects of muscarinic antagonists, as observed particularly for the long-acting muscarinic antagonist tiotropium. On the other hand, beta-adrenoceptor agonists, via activation of adenylyl cyclase, can also exert various inhibitory effects on pulmonary fibroblasts, and these anti-fibrotic effects are mimicked by other agents that cause an increase in intracellular cyclic adenosine monophosphate (cAMP), such as phosphodiesterase inhibitors or EP2 prostanoid receptor agonists. In addition, the role of the extracellular signal-regulated kinase-mitogen-activated protein kinase pathway, protein kinase A and exchange protein activated by cAMP (Epac) and potential interactions between these cellular signalling pathways are discussed.

Rationale for the major changes in the pharmacotherapy section of the National Asthma Education and Prevention Program guidelines

Numerous changes have been incorporated into the new National Asthma Education and Prevention Program's Expert Panel Report 3. In the pharmacotherapy section of the report, many of these changes are minor in that they do not alter the basic philosophy of treatment recommendations from the previous Expert Panel Report but only add new formulations, change dosing or dosage forms, or add discussion of risks. However, 4 major changes have been identified, and the rationales for 3 are discussed in detail here. The treatment of childhood asthma is divided into 2 distinct age groups, infants less than 5 years of age and children 5 to 12 years of age, because of the availability of more data suggesting differences in response in these patients, as well as a relative paucity of quality data in the younger patients. Omalizumab, a humanized mAb to IgE, is the only new entity approved for the treatment of asthma since the previous guidelines, and its recommendations were reviewed. The indication for combination therapy with inhaled corticosteroids and long-acting inhaled beta(2)-agonists (LABAs) has been modified in lieu of the recent black box warning concerning the increased risk of severe asthma exacerbations and death associated with LABA use. However, the inhaled corticosteroids/LABAs are still recommended for patients with moderate-to-severe persistent asthma. The rationale for the continued recommendation is provided.

Role of long-acting beta2-adrenergic agonists in asthma management based on updated asthma guidelines

PURPOSE OF REVIEW

This review examines the role of long-acting beta2-adrenergic agonists in the management of asthma, particularly focusing on recommendations in the newly revised Global Initiative for Asthma (GINA) and National Heart, Lung, and Blood Institute (NHLBI) asthma guidelines.

RECENT FINDINGS

GINA guidelines recommend increasing inhaled corticosteroid doses in all children with asthma not controlled on low-dose inhaled corticosteroids before adding a long-acting beta2-adrenergic agonist, whereas NHLBI guidelines have different age-based recommendations for children. In patients younger than 5 years, NHLBI guidelines recommend increasing the inhaled corticosteroid dose before adding a long-acting beta2-adrenergic agonist; in children aged 5-11 years, equal weight is given to increasing the inhaled corticosteroid dose or including add-on therapy to low-dose inhaled corticosteroids. In adults and adolescents aged 12 years and older, GINA recommends adding long-acting beta2-adrenergic agonists to low-dose inhaled corticosteroids over increasing the inhaled corticosteroid dose. NHLBI guidelines give equal weight to these choices, with alternative, although not preferred, therapies including the addition of theophylline, zileuton, or leukotriene receptor antagonists to low-dose inhaled corticosteroids.

SUMMARY

In the recently updated GINA and NHLBI asthma guidelines, long-acting beta2-adrenergic agonists are an important class of agents for the management of persistent asthma in patients whose asthma is not well controlled with inhaled corticosteroid monotherapy.

Tolerability profiles of leukotriene receptor antagonists and long-acting beta2-adrenoceptor agonists in combination with inhaled corticosteroids for treatment of asthma: a review

Inhaled corticosteroids, long-acting beta2-adrenoceptor agonists, and leukotriene receptor antagonists are widely used for treatment of asthma. Inhaled corticosteroids are recommended as first-line therapy, whereas long-acting beta2-adrenoceptor agonists and leukotriene receptor antagonists are indicated as add-on therapy in patients not adequately controlled with corticosteroids alone. A number of studies have investigated the efficacy of combinations of these drugs in asthma, but several issues concerning the safety of these treatments are highly debated. This review provides a critical appraisal of the tolerability profiles of long-acting beta2-agonists and leukotriene receptor antagonists used in combination with inhaled corticosteroids for the treatment of asthma.

Non-corticosteroid therapy for the long-term control of asthma

The non-corticosteroids approved for the maintenance therapy of persistent asthma include the long-acting inhaled beta(2) agonists (LABAs), leukotriene modifiers, chromones, theophylline and omalizumab. This review assesses the benefits and risks of each in relation to the inhaled corticosteroids and each other. Neither the LABAs nor omalizumab should be used as monotherapy for persistent asthma. There is no evidence of clinically significant differences in efficacy between the chromones, theophylline and leukotriene modifiers as monotherapy in mild-moderate persistent asthma; thus the choice of one therapy over the other is a clinical decision based upon differences in safety, acceptability to the patient and ease of use. Although there is significant variability in response to various therapies, non response to one therapy is not predictive of response to another. Neither studies of phenotypes nor genotypes have provided acceptable determinants of response as yet. As adjunctive therapy to the inhaled corticosteroids for moderate-severe persistent asthma, the LABAs provide superior improvement in lung function and reduction in exacerbations relative to higher doses of inhaled corticosteroids and the other noncorticosteroids used as adjunctive therapy. Thus, LABAs remain the adjunctive therapy of choice in patients not adequately controlled on low-medium dose inhaled corticosteroids. Omalizumab has not been compared with the other adjunctive therapies, so its relative efficacy is unknown. However, it is the only adjunctive therapy added to the combination of an inhaled corticosteroid plus LABA to demonstrate further improvement in a controlled clinical trial.

Optimal management of asthma in elderly patients: strategies to improve adherence to recommended interventions

Adherence to asthma medications presents a problem in all age groups, and older people with chronic illnesses such as asthma also have multiple co-morbidities and consequently complex healthcare needs. It has been suggested that older people are also less likely to adhere to medication and treatment than younger people. Although the prevalence of asthma in older people is similar to that of the general population, over two-thirds of those who die from asthma are >50 years of age and there is strong evidence for under-diagnosis. Clinicians therefore face specific challenges in providing healthcare with respect to both asthma diagnosis and treatment in older age groups. Non-adherence to medication can be defined as either 'intentional' or 'unintentional'. Unintentional non-adherence is more likely to be associated with sociodemographic or physical barriers to the use of medication. Intentional non-adherence results from the balance of individual reasoning of risks versus the benefits of taking medication and acceptance of asthma diagnosis. Intentional non-adherence can be addressed through strategies that influence health beliefs and concerns about the adverse effects of medicine. Unintentional adherence can be addressed by assessing and educating the patient in relation to device use and providing education and clear written instructions about medication requirements. However, some barriers to medication use, such as financial ones, may be systematic. Most studies of medication use, efficacy, adverse effects and adherence in patients with asthma primarily involve younger people. Studies of strategies to improve asthma adherence outcomes specifically in older people are urgently needed.

Getting to the heart of asthma: can "beta blockers" be useful to treat asthma?

beta(2)-adrenoceptor agonists are the mainstay for the acute symptomatic treatment of asthma and provide effective bronchoprotection to a wide range of bronchoconstrictor agents. However, over the past 4 decades there has been a continuing debate concerning whether regular chronic treatment with these drugs may be doing more harm than good. The FDA's recent decision to add black box warnings concerning the regular use of salmeterol- and formoterol-containing compounds, as well as their decision not to recommend agents containing long-acting beta(2)-adrenoceptor agonists as first-line therapy, seems to confirm the concerns regarding the regular use of the long-acting beta(2)-adrenoceptor agonists. A similar debate arose in the late 1980s concerning the use of beta-adrenoceptor agonists in the treatment of heart failure. In this disease, short-term use of beta agonists is associated with increased cardiac index and stroke volume, yet their long-term use is associated with increased morbidity and mortality. Moreover, certain beta blockers that are initially detrimental when used short term are now considered beneficial in the treatment of this disease when used chronically. Here, there is a parallel, as beta blockers are contraindicated in patients with asthma but the use of beta blockers chronically has never been evaluated. This begs the question of whether a similar paradigm shift is applicable in the treatment of asthma and whether under certain circumstances the long-term use of certain beta blockers may be useful in the treatment of this disease.

Beta2-agonists and bronchial hyperresponsiveness

Bronchial hyperresponsiveness (BHR) is a characteristic feature of asthma, and individuals with this disease respond to a range of physiological and chemical insults that are otherwise innocuous to healthy subjects, suggesting that the mechanisms underlying this phenomenon are characteristic of the asthma phenotype. BHR can be increased following exposure to environmental allergens in suitably sensitized individuals, pollutants, and certain viruses and can also be exacerbated by exposure to certain drugs, including nonsteroidal anti-inflammatory agents and beta-blockers. Although beta2-agonists administered acutely remain the treatment for the symptoms of asthma, paradoxically, regular treatment with these drugs can result in an increase in BHR, and this has been suggested to contribute to the increase in asthma morbidity and mortality that has been reported by numerous investigators. This article highlights our current understanding of this phenomenon and examines the potential mechanisms responsible for this effect.