Long-acting muscarinic antagonists: a potential add-on therapy in the treatment of asthma?

Biseugenol Exhibited Anti-Inflammatory and Anti-Asthmatic Effects in an Asthma Mouse Model of Mixed-Granulocytic Asthma

In the present work, the anti-inflammatory and antiasthmatic potential of biseugenol, isolated as the main component from n-hexane extract from leaves of Nectandra leucantha and chemically prepared using oxidative coupling from eugenol, was evaluated in an experimental model of mixed-granulocytic asthma. Initially, in silico studies of biseugenol showed good predictions for drug-likeness, with adherence to Lipinski’s rules of five (RO5), good Absorption, Distribution, Metabolism and Excretion (ADME) properties and no alerts for Pan-Assay Interference Compounds (PAINS), indicating adequate adherence to perform in vivo assays. Biseugenol (20 mg·kg⁻¹) was thus administered intraperitoneally (four days of treatment) and resulted in a significant reduction in both eosinophils and neutrophils of bronchoalveolar lavage fluid in ovalbumin-sensitized mice with no statistical difference from dexamethasone (5 mg·kg⁻¹). As for lung function parameters, biseugenol (20 mg·kg⁻¹) significantly reduced airway and tissue damping in comparison to ovalbumin group, with similar efficacy to positive control dexamethasone. Airway hyperresponsiveness to intravenous methacholine was reduced with biseugenol but was inferior to dexamethasone in higher doses. In conclusion, biseugenol displayed antiasthmatic effects, as observed through the reduction of inflammation and airway hyperresponsiveness, with similar effects to dexamethasone, on mixed-granulocytic ovalbumin-sensitized mice.

2020 Brazilian Thoracic Association recommendations for the management of asthma

The pharmacological management of asthma has changed considerably in recent decades, as it has come to be understood that it is a complex, heterogeneous disease with different phenotypes and endotypes. It is now clear that the goal of asthma treatment should be to achieve and maintain control of the disease, as well as to minimize the risks (of exacerbations, disease instability, accelerated loss of lung function, and adverse treatment effects). That requires an approach that is personalized in terms of the pharmacological treatment, patient education, written action plan, training in correct inhaler use, and review of the inhaler technique at each office visit. A panel of 22 pulmonologists was invited to perform a critical review of recent evidence of pharmacological treatment of asthma and to prepare this set of recommendations, a treatment guide tailored to use in Brazil. The topics or questions related to the most significant changes in concepts, and consequently in the management of asthma in clinical practice, were chosen by a panel of experts. To formulate these recommendations, we asked each expert to perform a critical review of a topic or to respond to a question, on the basis of evidence in the literature. In a second phase, three experts discussed and structured all texts submitted by the others. That was followed by a third phase, in which all of the experts reviewed and discussed each recommendation. These recommendations, which are intended for physicians involved in the treatment of asthma, apply to asthma patients of all ages.

G Protein-Coupled Receptors in Asthma Therapy: Pharmacology and Drug Action

Asthma is a heterogeneous inflammatory disease of the airways that is associated with airway hyperresponsiveness and airflow limitation. Although asthma was once simply categorized as atopic or nonatopic, emerging analyses over the last few decades have revealed a variety of asthma endotypes that are attributed to numerous pathophysiological mechanisms. The classification of asthma by endotype is primarily routed in different profiles of airway inflammation that contribute to bronchoconstriction. Many asthma therapeutics target G protein-coupled receptors (GPCRs), which either enhance bronchodilation or prevent bronchoconstriction. Short-acting and long-acting β 2-agonists are widely used bronchodilators that signal through the activation of the β 2-adrenergic receptor. Short-acting and long-acting antagonists of muscarinic acetylcholine receptors are used to reduce bronchoconstriction by blocking the action of acetylcholine. Leukotriene antagonists that block the signaling of cysteinyl leukotriene receptor 1 are used as an add-on therapy to reduce bronchoconstriction and inflammation induced by cysteinyl leukotrienes. A number of GPCR-targeting asthma drug candidates are also in different stages of development. Among them, antagonists of prostaglandin D2 receptor 2 have advanced into phase III clinical trials. Others, including antagonists of the adenosine A2B receptor and the histamine H4 receptor, are in early stages of clinical investigation. In the past decade, significant research advancements in pharmacology, cell biology, structural biology, and molecular physiology have greatly deepened our understanding of the therapeutic roles of GPCRs in asthma and drug action on these GPCRs. This review summarizes our current understanding of GPCR signaling and pharmacology in the context of asthma treatment. SIGNIFICANCE STATEMENT: Although current treatment methods for asthma are effective for a majority of asthma patients, there are still a large number of patients with poorly controlled asthma who may experience asthma exacerbations. This review summarizes current asthma treatment methods and our understanding of signaling and pharmacology of G protein-coupled receptors (GPCRs) in asthma therapy, and discusses controversies regarding the use of GPCR drugs and new opportunities in developing GPCR-targeting therapeutics for the treatment of asthma.

Safety of tiotropium Respimat® in black or African-American patients with symptomatic asthma

BACKGROUND

Black patients with asthma have a higher disease burden and greater morbidity compared with other racial/ethnic groups. Tiotropium Respimat^®, as add-on to at least inhaled corticosteroids (ICS), improves lung function and asthma control and reduces asthma exacerbation risk in patients, with a safety profile comparable with placebo. This study aimed to assess the safety of tiotropium Respimat^®, compared with placebo, in black or African-American patients.

METHODS

Data were pooled from 12 randomized, placebo-controlled, parallel-group, Phase II or III trials from the global Boehringer Ingelheim program with once-daily tiotropium Respimat^® (5 μg or 2.5 μg). Trial participants had symptomatic persistent asthma with a broad range of severities and were aged 1-75 years. The safety results of black or African-American patients were compared with the overall trial population.

RESULTS

Of the 5165 patients treated with tiotropium or placebo, 3.2% were black or African American. For both doses of tiotropium, the proportion of patients reporting adverse events (AEs) was approximately 10% lower compared with placebo and was generally comparable with the proportion of patients reporting AEs in all groups of the overall population. The number of investigator-assessed drug-related AEs, AEs leading to trial drug discontinuation or serious AEs reported by patients was low and comparable between treatment groups and with the overall population.

CONCLUSION

Tiotropium Respimat^® appears to be a generally safe add-on bronchodilator treatment option to ICS with or without other controllers in pediatric and adult black or African-American patients with asthma.

CLINICAL TRIAL IDENTIFIERS

NCT01634113, NCT01634139, NCT01634152, NCT01257230, NCT01277523, NCT01316380, NCT00350207, NCT01172808, NCT01172821, NCT01340209, NCT00772538, NCT00776984.

Barriers to achieving asthma control in adults: evidence for the role of tiotropium in current management strategies

Despite the availability of a range of treatment options and management guidelines, a high proportion of adults with asthma remain uncontrolled. The challenge of managing uncontrolled asthma includes providing efficacious treatment while limiting side effects, recognizing situations when a change in asthma therapy is required, and considering patient preferences and satisfaction. In line with the Global Initiative for Asthma report, asthma management is based on a backbone of inhaled corticosteroid (ICS) therapy and use of add-on therapies to achieve disease control. This review considers whether add-on options could be better utilized in clinical practice. A number of long-acting muscarinic antagonists are in development, but tiotropium is the most widely studied for use in asthma. Evidence demonstrating the efficacy of tiotropium as an add-on therapy to at least ICS in adults with symptomatic mild, moderate, and severe asthma is presented from randomized controlled trials and real-world evidence. In addition, the benefit of tiotropium therapy in a wide range of patient phenotypes and disease severities without the need for biomarker assessment is discussed. Additional strategies that complement this approach, such as recognizing and overcoming barriers to adherence, ensuring optimal device use, and education and support to enhance patient–physician communication, are discussed. Physician education can also help raise awareness that additional management options are available for patients with moderate-to-severe asthma who remain uncontrolled on ICS/long-acting β₂-agonist treatment.

Clinical efficacy and safety of anticholinergic therapies in pediatric patients

The burden of uncontrolled asthma in children and adolescents is high. Treatment options for pediatric patients (aged under 18 years) with asthma are largely influenced by the Global Initiative for Asthma recommendations. Algorithms for adolescents (12-18 years) and adults are identical, but recommendations for children aged under 6 years and 6-11 years differ. Although the goals of treatment for pediatric patients with asthma are similar to those for adults, relatively few new therapies have been approved for this patient population within the last decade. Designing clinical trials involving children presents several challenges, notably that children are often less able to perform lung function tests, and traditional endpoints used in clinical trials with adults, such as forced expiratory volume in 1 second, asthma exacerbations and questionnaires, have limitations associated with their use in children. There are also ethical considerations related to the performance of longer placebo-controlled exacerbation trials. This review considers additional clinical endpoints to those traditionally reported, including forced expiratory flow at 25%-75% of forced vital capacity, which may help shed light on which treatments are most effective for use in pediatric patients with asthma. The pros and cons of specific and potentially clinically relevant endpoints are considered, along with device considerations and patient preferences that may enhance adherence and quality of life. Recent advances in the management of children and adolescents, including the US Food and Drug Administration and European Medicines Agency approval of tiotropium in patients with asthma aged 6 years and over, are also discussed.

Tiotropium for asthma: A summary of current guidelines and a case study

BACKGROUND AND PURPOSE

The long-acting muscarinic antagonist tiotropium received an indication for the treatment of asthma from the FDA in 2015.

METHODS

This paper summarizes much of the published findings on tiotropium and asthma and explores the heterogeneity of the asthma population vis-à-vis recent changes in guidelines for management of COPD. The accompanying case study provides an illustration of how tiotropium might be added to a patient's regimen appropriately.

CONCLUSIONS AND IMPLICATIONS FOR PRACTICE

Tiotropium has been shown in many studies to be beneficial to patients with asthma as an add-on medication. It should be considered as an agent by the clinician managing patients with both allergic and non-allergic asthma.

Pharmacokinetics of Single and Repeat Doses of Fluticasone Furoate/Umeclidinium/Vilanterol in Healthy Chinese Adults

The pharmacokinetics (PK) and safety of single-inhaler fluticasone furoate/umeclidinium/vilanterol (FF/UMEC/VI) after single and repeat dosing in healthy Chinese adults were assessed. In this open-label study (NCT02837380), subjects received once-daily FF/UMEC/VI 100/62.5/25 µg on day 1 and repeat doses on days 2-7. PK parameters (days 1 and 7) included maximum observed concentration (C_max ) and area under the plasma concentration-time curve (AUC) from time zero (predose) to last time of quantifiable concentration (AUC_0-t ). Terminal phase half-life (t_½ ) on day 1 was estimated. The primary objective was to assess systemic exposure of FF 100 µg, UMEC 62.5 µg, and VI 25 µg following single-inhaler triple therapy on days 1 and 7. On day 1, geometric mean t_½ of UMEC and VI was 0.36 and 0.52 hours, respectively; t_½ of FF was not representative because of nonquantifiable concentration data. On days 1 and 7, geometric mean C_max of FF was 10.46 and 27.32 pg/mL, respectively; C_max of UMEC was 144.14 and 241.35 pg/mL, respectively; and C_max of VI was 120.42 and 196.78 pg/mL, respectively. AUC_0-t of FF was 1.77 and 276.96 pg·h/mL, respectively; AUC_0-t of UMEC was 28.44 and 117.19 pg·h/mL, respectively; and AUC_0-t of VI, 42.46 and 101.12 pg·h/mL, respectively. The PK of FF/UMEC/VI was as expected for the individual-component PK previously reported in healthy Chinese adults. No new safety signals were observed.

The mode of action of anticholinergics in asthma

Acetylcholine binds to muscarinic receptors to play a key role in the pathophysiology of asthma, leading to bronchoconstriction, increased mucus secretion, inflammation and airway remodelling. Anticholinergics are muscarinic receptor antagonists that are used in the treatment of chronic obstructive pulmonary disease and asthma. Recent in vivo and in vitro data have increased our understanding of how acetylcholine contributes to the disease manifestations of asthma, as well as elucidating the mechanism of action of anticholinergics. This review assesses the latest literature on acetylcholine in asthma pathophysiology, with a closer look at its role in airway inflammation and remodelling. New insights into the mechanism of action of anticholinergics, their effects on airway remodelling, and a review of the efficacy and safety of long-acting anticholinergics in asthma treatment will also be covered, including a summary of the latest clinical trial data.

Pre-clinical data suggest that anticholinergics can reduce acetylcholine-induced airway inflammation and remodellinghttp://ow.ly/xqAQ30loP8F

Fluoxetine protects against OVA induced bronchial asthma and depression in rats

Depression is very common in asthmatic patients and may increases risk for morbidity and mortality. The present work aimed to investigate the protective effect of fluoxetine, on behavioral and biochemical changes, associated with ovalbumin (OVA) - induced bronchial asthma and depression in rats. Rats were sensitized with intraperitoneal administration of OVA plus aluminum hydroxide for 3 consecutive days then at day 11 followed by OVA intranasal challenge at days 19, 20, 21. Rats were either pretreated with dexamethasone, fluoxetine10mg/kg or fluoxetine 20 mg/kg. At the end of the experiment, various tests were performed, including open field, forced swimming and respiratory function tests. Blood was drawn for serum IgE detection. Finally, rats were euthanized, brain-derived neurotrophic factor (BDNF) was estimated in bronchoalveolar lavage (BAL) fluid and lung content of reduced glutathione (GSH), superoxide dismutase (SOD), tumor necrosis factor-alpha (TNF-α) and interleukin 4 (IL-4) were determined. Histopathological study was also performed. The results showed that fluoxetine significantly ameliorated OVA- induced biochemical and behavioral changes. Fluoxetine may protect against OVA-induced asthma and depression in rats. This effect may be mediated at least in part by its antioxidant, anti-inflammatory and immunosuppressant effect.

Is there a role for inhaled anticholinergic therapy in asthma management?

Anticholinergic therapy has long been a cornerstone of management of chronic obstructive pulmonary disease (COPD) but has not been included in treatment guidelines for asthma. In September 2015, tiotropium bromide was approved for use in adults with asthma; the indication has since been expanded to children ages 6 years and older. This article discusses appropriate patient selection and dosing, and the role of tiotropium bromide in asthma management.

Anticholinergic drugs in asthma therapy

PURPOSE OF REVIEW

Current guidelines recommend a stepwise approach for pharmacological therapy aimed to achieve and maintain asthma control. Despite these recommendations, at least 50% of patients continue to be uncontrolled with risk of asthma exacerbations that can often be serious and are associated with deterioration of quality of life. In recent years, the interest in anticholinergic bronchodilators, which have been primarily used in the treatment of chronic obstructive pulmonary disease, has increased patients with uncontrolled asthma. This review analyzes the mechanisms for the proposed clinical use of anticholinergic bronchodilators as an adjunctive therapy in asthma.

RECENT FINDINGS

Based on existing and recent evidence, the use of anticholinergic bronchodilators, particularly long-acting muscarinic antagonists (LAMAs), plays an important role as add-on therapy in patients uncontrolled on existing therapies. In particular, the use of anticholinergics in asthma may have a role in patients intolerant to long-acting β2 agonist, in patients with certain pharmacogenetic profiles and in those patients with asthma symptoms mostly at night.

SUMMARY

Data from clinical trials and from real-life confirm the safety and efficacy of LAMAs, especially tiotropium, in patients who remain uncontrolled despite the use of inhaled corticosteroid therapy.

Management of severe asthma: targeting the airways, comorbidities and risk factors

Severe asthma is a complex heterogeneous disease that is refractory to standard treatment and is complicated by multiple comorbidities and risk factors. In mild to moderate asthma, the burden of disease can be minimised by inhaled corticosteroids, bronchodilators and self-management education. In severe asthma, however, management is more complex. When patients with asthma continue to experience symptoms and exacerbations despite optimal management, severe refractory asthma (SRA) should be suspected and confirmed, and other aetiologies ruled out. Once a diagnosis of SRA is established, patients should undergo a systematic and multidimensional assessment to identify inflammatory endotypes, risk factors and comorbidities, with targeted and individualised management initiated. We describe a practical approach to assessment and management of patients with SRA.

Tiotropium added to low- to medium-dose inhaled corticosteroids (ICS) versus low- to medium-dose ICS alone for adults with mild to moderate uncontrolled persistent asthma: A systematic review and meta-analysis

OBJECTIVE

To assess the efficacy and safety profile of tiotropium when added to low- to medium-dose inhaled corticosteroid (ICS) regimen versus low- to medium-dose ICS alone for adults with mild to moderate uncontrolled persistent asthma.

DATA SOURCES

The online databases Pubmed, Embase and the Cochrane Library were searched for relevant data published up to November 14, 2017; we also conducted a supplementary search using clinicaltrials.gov.

STUDY SELECTIONS

Only randomized control trials were included in this review.

RESULTS

Four studies met our inclusion criteria for this review. In our review, two crossover studies were rated as "high risk" in the domain of "other bias" because a washout was not performed between each intervention. Lung function was significantly improved in the patient group receiving low- to medium-dose ICS with tiotropium. Results were consistent between each of three subgroups (tiotropium dry powder inhaler 18 μg or Respimat Soft Mist inhaler 5 µg, Respimat Soft Mist inhaler 2.5 μg, and Respimat Soft Mist inhaler 1.25 μg). Although no significant difference in Asthma Control Questionnaire (ACQ) score was found between the two treatment groups, substantial heterogeneity was observed. The incidence of serious adverse events between the two treatment groups was not statistically significant.

CONCLUSIONS

Tiotropium as a once daily add-on to low- to medium-dose ICS may be efficacious and well-tolerated treatment in adults with moderate uncontrolled asthma. However, as only a few studies were identified, more studies of better design and long-term trial duration are required in the future.

The underlying physiological mechanisms whereby anticholinergics alleviate asthma

The mechanisms whereby anticholinergics improve asthma outcomes, such as lung function, symptoms, and rate of exacerbation, can be numerous. The most obvious is by affecting the contraction of airway smooth muscle (ASM). The acetylcholine released from the cholinergic nerves is the most important bronchoconstrictor that sets the baseline degree of contractile activation of ASM in healthy individuals. Although the degree of ASM's contractile activation can also be fine-tuned by a plethora of other bronchoconstrictors and bronchodilators in asthma, blocking the ceaseless effect of acetylcholine on ASM by anticholinergics reduces, at any given moment, the overall degree of contractile activation. Because the relationships that exist between the degree of contractile activation, ASM force, ASM shortening, airway narrowing, airflow resistance, and respiratory resistance are not linear, small decreases in the contractile activation of ASM can be greatly amplified and thus translate into important benefits to a patient's well-being. Plus, many inflammatory and remodeling features that are often found in asthmatic lungs synergize with the contractile activation of ASM to increase respiratory resistance. This review recalls that the proven effectiveness of anticholinergics in the treatment of asthma could be merely attributed to a small reduction in the contractile activation of ASM.

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.

Comparison of the in vitro pharmacological profiles of long-acting muscarinic antagonists in human bronchus

BACKGROUND AND PURPOSE

Long-acting muscarinic antagonists (LAMAs) have been recommended for the treatment of chronic obstructive pulmonary disease and (more recently) asthma. However, the in vitro pharmacological profiles of the four LAMAs currently marketed (tiotropium, umeclidinium, aclidinium and glycopyrronium) have not yet been compared (relative to ipratropium) by using the same experimental approach.

EXPERIMENTAL APPROACH

With a total of 560 human bronchial rings, we investigated the antagonists' potency, onset and duration of action for inhibition of the contractile response evoked by electrical field stimulation. We also evaluated the antagonists' potency for inhibiting cumulative concentration-contraction curves for acetylcholine and carbachol.

KEY RESULTS

The onset and duration of action were concentration-dependent. At submaximal, equipotent concentrations, the antagonists' onsets of action were within the same order of magnitude. However, the durations of action differed markedly. After washout, ipratropium's inhibitory activity decreased rapidly (within 30-90 min) but those of tiotropium and umeclidinium remained stable (at above 70%) for at least 9 h. Aclidinium and glycopyrronium displayed less stable inhibitory effects, with a progressive loss of inhibition at submaximal concentrations. In contrast to ipratropium, all the LAMAs behaved as insurmountable antagonists by decreasing the maximum responses to both acetylcholine and carbachol.

CONCLUSIONS AND IMPLICATIONS

The observed differences in the LAMAs' in vitro pharmacological profiles in the human bronchus provide a compelling pharmacological rationale for the differences in the drugs' respective recommended daily doses and frequencies of administration.

A randomised clinical trial of feedback on inhaler adherence and technique in patients with severe uncontrolled asthma

In severe asthma, poor control could reflect issues of medication adherence or inhaler technique, or that the condition is refractory. This study aimed to determine if an intervention with (bio)feedback on the features of inhaler use would identify refractory asthma and enhance inhaler technique and adherence.Patients with severe uncontrolled asthma were subjected to a stratified-by-site random block design. The intensive education group received repeated training in inhaler use, adherence and disease management. The intervention group received the same intervention, enhanced by (bio)feedback-guided training. The primary outcome was rate of actual inhaler adherence. Secondary outcomes included a pre-defined assessment of clinical outcome. Outcome assessors were blinded to group allocation. Data were analysed on an intention-to-treat and per-protocol basis.The mean rate of adherence during the third month in the (bio)feedback group (n=111) was higher than that in the enhanced education group (intention-to-treat, n=107; 73% versus 63%; 95% CI 2.8%-17.6%; p=0.02). By the end of the study, asthma was either stable or improved in 54 patients (38%); uncontrolled, but poorly adherent in 52 (35%); and uncontrolled, but adherent in 40 (27%).Repeated feedback significantly improved inhaler adherence. After a programme of adherence and inhaler technique assessment, only 40 patients (27%) were refractory and adherent, and might therefore need add-on therapy.

The evolving role of tiotropium in asthma

Tiotropium is a long-acting muscarinic antagonist (LAMA) that exerts its bronchodilatory effect by blocking endogenous acetylcholine receptors in the airways. Its safety and efficacy are well established for the treatment of COPD, and it is now being recognized for its role in improving lung function and control in asthma. This review discusses the evolving role of tiotropium delivered by the Respimat® in patients across the range of asthma severities and ages, and provides an overview of safety and efficacy data. Tiotropium is the only LAMA currently approved for the treatment of asthma, and evidence from a large-scale clinical trial program, including several Phase III studies in adults, has demonstrated that tiotropium improves lung function and asthma control, with a safety profile comparable with that of placebo. Clinical trials in adolescent patients (aged 12-17 years) have also shown improvements in lung function and trends toward improved asthma control. Of note, the efficacy and safety profiles are consistent regardless of baseline characteristics and phenotype. Given the large and growing body of evidence, it is likely that as clinical experience with tiotropium increases, this treatment may possibly emerge as the key choice for add-on therapy to inhaled corticosteroids/long-acting β2-agonists, and in patients who do not tolerate long-acting bronchodilators or other medications, in the future.

Multidimensional assessment of severe asthma: A systematic review and meta-analysis

The management of severe asthma is complex. Multidimensional assessment (MDA) of specific traits has been proposed as an effective strategy to manage severe asthma, although it is supported by few prospective studies. We aimed to systematically review the literature published on MDA in severe asthma, to identify the traits included in MDA and to determine the effect of MDA on asthma-related outcomes. We identified 26 studies and classified these based on study type (cohort/cross-sectional studies; experimental/outcome studies; and severe asthma disease registries). Study type determined the comprehensiveness of the assessment. Assessed traits were classified into three domains (airways, co-morbidities and risk factors). The airway domain had the largest number of traits assessed (mean ± SD = 4.2 ± 1.7) compared with co-morbidities (3.6 ± 2.2) and risk factors (3.9 ± 2.1). Bronchodilator reversibility and airflow limitation were assessed in 92% of studies, whereas airway inflammation was only assessed in 50%. Commonly assessed co-morbidities were psychological dysfunction, sinusitis (both 73%) and gastro-oesophageal reflux disease (GORD; 69%). Atopic and smoking statuses were the most commonly assessed risk factors (85% and 86%, respectively). There were six outcome studies, of which five concluded that MDA is effective at improving asthma-related outcomes. Among these studies, significantly more traits were assessed than treated. MDA studies have assessed a variety of different traits and have shown evidence of improved outcomes. This promising model of care requires more research to inform which traits should be assessed, which traits should be treated and what effect MDA has on patient outcomes.

Mechanisms, measurement and management of exertional dyspnoea in asthma: Number 5 in the Series "Exertional dyspnoea" Edited by Pierantonio Laveneziana and Piergiuseppe Agostoni

Asthma is a heterogeneous condition, with dyspnoea during exercise affecting individuals to a variable degree. This narrative review explores the mechanisms and measurement of exertional dyspnoea in asthma and summarises the available evidence for the efficacy of various interventions on exertional dyspnoea. Studies on the mechanisms of dyspnoea in asthma have largely utilised direct bronchoprovocation challenges, rather than exercise, which may invoke different physiological mechanisms. Thus, the description of dyspnoea during methacholine challenge can differ from what is experienced during daily activities, including exercise. Dyspnoea perception during exercise is influenced by many interacting variables, such as asthma severity and phenotype, bronchoconstriction, dynamic hyperinflation, respiratory drive and psychological factors. In addition to the intensity of dyspnoea, the qualitative description of dyspnoea may give important clues as to the underlying mechanism and may be an important endpoint for future interventional studies. There is currently little evidence demonstrating whether pharmacological or non-pharmacological interventions specifically improve exertional dyspnoea, which is an important area for future research.

The impact of poor asthma control among asthma patients treated with inhaled corticosteroids plus long-acting β2-agonists in the United Kingdom: a cross-sectional analysis

There are several new treatment options for patients whose asthma remains uncontrolled on free-dose and fixed-dose combinations of inhaled corticosteroids plus long-acting β₂-agonists (ICS+LABA). In order to evaluate the likely impact of these treatments, we assessed the effect of uncontrolled asthma on healthcare and patient burden within the UK among adult patients treated with ICS+LABA. Data obtained from 2010–2011 UK National Health and Wellness Surveys identified 701 patients treated with ICS+LABA. Patients with not well-controlled asthma (Asthma Control Test™ score <20) were compared with well-controlled asthma (score ≥ 20) patients on multiple measures. Cost burden was calculated using healthcare resource utilisation models and work productivity and impairment questionnaire. Overall, 452 and 249 patients reported not well-controlled and well-controlled asthma, respectively. A greater proportion of not well-controlled patients visited the accident & emergency department (21 vs. 14%, P = 0.016), were hospitalised (13 vs. 8%, P = 0.022) and had lower mental and physical health-related quality of life (P < 0.001) and impaired work productivity and activity scores: presenteeism (23 vs. 11%, P < 0.001), work impairment (29 vs. 17%, P < 0.001) and activity impairment (46 vs. 24%, P < 0.001). Calculated direct and indirect yearly costs/person doubled among not well-controlled compared to well-controlled asthma patients (£6592 vs. £3220). Total cost to society was estimated at £6172 million/year (direct costs, £1307 million; indirect costs, £4865 million). In conclusion, not well-controlled asthma is common among UK adults treated with ICS+LABA, resulting in impairments across a number of important health outcomes and represents a significant unmet need and resource burden.

Many people who take inhaled steroids combined with long-acting β2-agonist drugs still have poorly controlled asthma. A team led by Ian Pavord from the University of Oxford, UK, identified 701 people from the 2010–2011 UK National Health and Wellness Surveys who were taking this drug combination for their asthma. The researchers found that nearly two-thirds of these individuals had poorly controlled asthma associated with more visits to the emergency room, worse quality of life (both mentally and physically), impaired productivity and other health problems. The calculated direct and indirect costs per person with poorly controlled asthma were about double that for someone whose asthma was under control. The authors conclude that better treatment and management is needed to reduce costs and address the unmet medical need for people with persistent uncontrolled asthma.

Drugs Interfering with Muscarinic Acetylcholine Receptors and Their Effects on Place Navigation

Muscarinic acetylcholine receptors (mAChRs) have been found to regulate many diverse functions, ranging from motivation and feeding to spatial navigation, an important and widely studied type of cognitive behavior. Systemic administration of non-selective antagonists of mAChRs, such as scopolamine or atropine, have been found to have adverse effects on a vast majority of place navigation tasks. However, many of these results may be potentially confounded by disruptions of functions other than spatial learning and memory. Although studies with selective antimuscarinics point to mutually opposite effects of M1 and M2 receptors, their particular contribution to spatial cognition is still poorly understood, partly due to a lack of truly selective agents. Furthermore, constitutive knock-outs do not always support results from selective antagonists. For modeling impaired spatial cognition, the scopolamine-induced amnesia model still maintains some limited validity, but there is an apparent need for more targeted approaches such as local intracerebral administration of antagonists, as well as novel techniques such as optogenetics focused on cholinergic neurons and chemogenetics aimed at cells expressing metabotropic mAChRs.