Safety of regular formoterol or salmeterol in adults with asthma: an overview of Cochrane reviews

Clinical utility of overviews on adverse events of pharmacological interventions

BACKGROUND

Overviews (i.e., systematic reviews of systematic reviews, meta-reviews, umbrella reviews) are a relatively new type of evidence synthesis. Among others, one reason to conduct an overview is to investigate adverse events (AEs) associated with a healthcare intervention. Overviews aim to provide easily accessible information for healthcare decision-makers including clinicians. We aimed to evaluate the clinical utility of overviews investigating AEs.

METHODS

We used a sample of 27 overviews exclusively investigating drug-related adverse events published until 2021 identified in a prior project. We defined clinical utility as the extent to which overviews are perceived to be useful in clinical practice. Each included overview was assigned to one of seven pharmacological experts with expertise on the topic of the overview. The clinical utility and value of these overviews were determined using a self-developed assessment tool. This included four open-ended questions and a ranking of three clinical utility statements completed by clinicians. We calculated frequencies for the ranked clinical utility statements and coded the answers to the open-ended questions using an inductive approach.

RESULTS

The overall agreement with the provided statements was high. According to the assessments, 67% of the included overviews generated new knowledge. In 93% of the assessments, the overviews were found to add value to the existing literature. The overviews were rated as more useful than the individual included systematic reviews (SRs) in 85% of the assessments. The answers to the open-ended questions revealed two key aspects of clinical utility in the included overviews. Firstly, it was considered useful that they provide a summary of available evidence (e.g., along with additional assessments, or across different populations, or in different settings that have not been evaluated together in the included SRs). Secondly, it was found useful if overviews conducted a new meta-analysis to answer specific research questions that had not been answered previously.

CONCLUSIONS

Overviews on drug-related AEs are considered valuable for clinical practice by clinicians. They can make available evidence on AEs more accessible and provide a comprehensive view of available evidence. As the role of overviews evolves, investigations such as this can identify areas of value.

Feedback of actionable individual patient prescription data to improve asthma prescribing: pragmatic cluster randomised trial in 233 UK general practices

BACKGROUND

Potentially inappropriate prescribing (PIP) of asthma bronchodilator inhalers is associated with increased morbidity and mortality.

AIM

To evaluate the effectiveness of feedback on the PIP of bronchodilator inhalers.

DESIGN AND SETTING

Pragmatic cluster randomised trial involving 235 of 244 (96.3%) GP practices in one Scottish health board.

METHOD

Practices were randomly allocated (1:1 ratio) to individualised feedback (including visualised medication histories for each patient and action-oriented messages) on PIP of bronchodilator inhalers from prescription data; feedback reports were sent in July 2015, February 2016, and August 2016. Controls were sent feedback on an unrelated subject. The primary outcome was the change in the mean number of patients per practice with PIP of bronchodilator inhalers from the baseline period (August 2014-July 2015) until the post-feedback period (February 2016-January 2017), identified through a composite of five individual measures using prescription data.

RESULTS

In the analysis of the primary outcome, the mean number of patients with PIP of bronchodilator inhalers fell in the 118 practices that were sent feedback from 21.8 per practice to 17.7 per practice. Numbers fell marginally in the 115 control practices, from 20.5 per practice to 20.2 per practice, with a statistically significant difference between the two groups. There were 3.7 fewer patients per practice with PIP of bronchodilator inhalers in the intervention practices versus the control practices (95% confidence interval = -5.3 to -2.0).

CONCLUSION

Individualised feedback of PIP of asthma bronchodilators that included background information, visualised medication histories for each patient, and action-oriented messages was effective at reducing the number of patients exposed to excess or unsafe prescribing of bronchodilator inhalers.

Asthma and obesity: endotoxin another insult to add to injury?

Low-grade inflammation is often an underlying cause of several chronic diseases such as asthma, obesity, cardiovascular disease, and type 2 diabetes mellitus (T2DM). Defining the mediators of such chronic low-grade inflammation often appears dependent on which disease is being investigated. However, downstream systemic inflammatory cytokine responses in these diseases often overlap, noting there is no doubt more than one factor at play to heighten the inflammatory response. Furthermore, it is increasingly believed that diet and an altered gut microbiota may play an important role in the pathology of such diverse diseases. More specifically, the inflammatory mediator endotoxin, which is a complex lipopolysaccharide (LPS) derived from the outer membrane cell wall of Gram-negative bacteria and is abundant within the gut microbiota, and may play a direct role alongside inhaled allergens in eliciting an inflammatory response in asthma. Endotoxin has immunogenic effects and is sufficiently microscopic to traverse the gut mucosa and enter the systemic circulation to act as a mediator of chronic low-grade inflammation in disease. Whilst the role of endotoxin has been considered in conditions of obesity, cardiovascular disease and T2DM, endotoxin as an inflammatory trigger in asthma is less well understood. This review has sought to examine the current evidence for the role of endotoxin in asthma, and whether the gut microbiota could be a dietary target to improve disease management. This may expand our understanding of endotoxin as a mediator of further low-grade inflammatory diseases, and how endotoxin may represent yet another insult to add to injury.

The impact of asthma on in-hospital outcomes of COVID-19 patients

OBJECTIVE

The impact of asthma as a possible risk factor for adverse clinical outcomes in patients diagnosed with COVID-19 remains controversial. The purpose of this study was to examine the impact of asthma on adverse clinical outcomes in a COVID-19 hospitalized cohort.

METHODS

Retrospective, propensity-matched observational study of consecutive COVID-19-positive patients between February 24, 2020, and November 3, 2020 at a single health care system.

RESULTS

In the initial population of 1925 patients, 4.4% presented with asthma. Propensity score matching reduced the total sample to n = 1045: 88 (8.4%) with asthma and n = 957 without asthma. A total of 164 (15.7%) patients died during the hospitalization, including 7 (8.0%) in the asthma group and 157 (16.4%), p = .037, in the non-asthmatic cohort. There was no difference between these groups in need for mechanical ventilation, length of stay on a ventilator, or hospital length of stay.Logistic regression analysis demonstrated that asthma was an independent predictor of lower mortality, while older age, BMI > 30 kg/m², heart failure, chronic kidney disease, and admission National Early Warning Score (NEWS) were significantly associated with an increased risk of in-hospital death. There were no significant differences between asthmatic and non-asthmatic cohorts with respect to need for mechanical ventilation, length of mechanical ventilation, serum markers of severe COVID-19 disease, or overall length of hospital stay.

CONCLUSION

We conclude that asthma in hospitalized COVID-19 patients is associated with a lower risk of mortality and no increase in disease severity in hospitalized COVID-19 patients.

Inhaled steroids with and without regular salmeterol for asthma: serious adverse events

BACKGROUND

Epidemiological evidence has suggested a link between use of beta₂-agonists and increased asthma mortality. Much debate has surrounded possible causal links for this association, and whether regular (daily) long-acting beta₂-agonists (LABAs) are safe, particularly when used in combination with inhaled corticosteroids (ICSs). This is an update of a Cochrane Review that now includes data from two large trials including 11,679 adults and 6208 children; both were mandated by the US Food and Drug Administration (FDA).  OBJECTIVES: To assess risks of mortality and non-fatal serious adverse events (SAEs) in trials that randomised participants with chronic asthma to regular salmeterol and ICS versus the same dose of ICS.

SEARCH METHODS

We identified randomised trials using the Cochrane Airways Group Specialised Register of trials. We checked websites of clinical trials registers for unpublished trial data. We also checked FDA submissions in relation to salmeterol. The date of the most recent search was 10 October 2018.

SELECTION CRITERIA

We included parallel-design randomised trials involving adults, children, or both with asthma of any severity who were randomised to treatment with regular salmeterol and ICS (in separate or combined inhalers) versus the same dose of ICS of at least 12 weeks in duration.

DATA COLLECTION AND ANALYSIS

We conducted the review according to standard procedures expected by Cochrane. We obtained unpublished data on mortality and SAEs from the sponsors, from ClinicalTrials.gov, and from FDA submissions. We assessed our confidence in the evidence according to current GRADE recommendations.

MAIN RESULTS

We have included in this review 41 studies (27,951 participants) in adults and adolescents, along with eight studies (8453 participants) in children. We judged that the overall risk of bias was low for all-cause events, and we obtained data on SAEs from all study authors. All except 542 adults (and none of the children) were given salmeterol and fluticasone in the same (combination) inhaler.DeathsEleven of a total of 14,233 adults taking regular salmeterol and ICS died, as did 13 of 13,718 taking regular ICS at the same dose. The pooled Peto odds ratio (OR) was 0.80 (95% confidence interval (CI) 0.36 to 1.78; participants = 27,951; studies = 41; I² = 0%; moderate-certainty evidence). In other words, for every 1000 adults treated for 25 weeks, one death occurred among those on ICS alone, and the corresponding risk among those taking salmeterol and ICS was also one death (95% CI 0 to 2 deaths).No children died, and no adults or children died of asthma, so we remain uncertain about mortality in children and about asthma mortality in any age group.Non-fatal serious adverse eventsA total of 332 adults receiving regular salmeterol with ICS experienced a non-fatal SAE of any cause, compared to 282 adults receiving regular ICS. The pooled Peto OR was 1.14 (95% CI 0.97 to 1.33; participants = 27,951; studies = 41; I² = 0%; moderate-certainty evidence). For every 1000 adults treated for 25 weeks, 21 adults on ICS alone had an SAE, and the corresponding risk for those on salmeterol and ICS was 23 adults (95% CI 20 to 27).Sixty-five of 4229 children given regular salmeterol with ICS suffered an SAE of any cause, compared to 62 of 4224 children given regular ICS. The pooled Peto OR was 1.04 (95% CI 0.73 to 1.48; participants = 8453; studies = 8; I² = 0%; moderate-certainty evidence). For every 1000 children treated for 23 weeks, 15 children on ICS alone had an SAE, and the corresponding risk for those on salmeterol and ICS was 15 children (95% CI 11 to 22).Asthma-related serious adverse eventsEighty and 67 adults in each group, respectively, experienced an asthma-related non-fatal SAE. The pooled Peto OR was 1.15 (95% CI 0.83 to 1.59; participants = 27,951; studies = 41; I² = 0%; low-certainty evidence). For every 1000 adults treated for 25 weeks, five receiving ICS alone had an asthma-related SAE, and the corresponding risk among those on salmeterol and ICS was six adults (95% CI 4 to 8).Twenty-nine children taking salmeterol and ICS and 23 children taking ICS alone reported asthma-related events. The pooled Peto OR was 1.25 (95% CI 0.72 to 2.16; participants = 8453; studies = 8; I² = 0%; moderate-certainty evidence). For every 1000 children treated for 23 weeks, five receiving an ICS alone had an asthma-related SAE, and the corresponding risk among those receiving salmeterol and ICS was seven children (95% CI 4 to 12).

AUTHORS' CONCLUSIONS

We did not find a difference in the risk of death or serious adverse events in either adults or children. However, trial authors reported no asthma deaths among 27,951 adults or 8453 children randomised to regular salmeterol and ICS or ICS alone over an average of six months. Therefore, the risk of dying from asthma on either treatment was very low, but we remain uncertain about whether the risk of dying from asthma is altered by adding salmeterol to ICS.Inclusion of new trials has increased the precision of the estimates for non-fatal SAEs of any cause. We can now say that the worst-case estimate is that at least 152 adults and 139 children must be treated with combination salmeterol and ICS for six months for one additional person to be admitted to the hospital (compared to treatment with ICS alone). These possible risks still have to be weighed against the benefits experienced by people who take combination treatment.However more than 90% of prescribed treatment was taken in the new trials, so the effects observed may be different from those seen with salmeterol in combination with ICS in daily practice.

Long-Acting β2-Agonists in Asthma: Enantioselective Safety Studies are Needed

Long-acting β2-agonists (LABAs) such as formoterol and salmeterol are used for prolonged bronchodilatation in asthma, usually in combination with inhaled corticosteroids (ICSs). Unexplained paradoxical asthma exacerbations and deaths have been associated with LABAs, particularly when used without ICS. LABAs clearly demonstrate effective bronchodilatation and steroid-sparing activity, but long-term treatment can lead to tolerance of their bronchodilator effects. There are also concerns with regard to the effects of LABAs on bronchial hyperresponsiveness (BHR), where long-term use is associated with increased BHR and loss of bronchoprotection. A complicating factor is that formoterol and salmeterol are both chiral compounds, usually administered as 50:50 racemic (rac-) mixtures of two enantiomers. The chiral nature of these compounds has been largely forgotten in the debate regarding LABA safety and effects on BHR, particularly that (S)-enantiomers of β2-agonists may be deleterious to asthma control. LABAs display enantioselective pharmacokinetics and pharmacodynamics. Biological plausibility of the deleterious effects of β2-agonists (S)-enantiomers is provided by in vitro and in vivo studies from the short-acting β2-agonist (SABA) salbutamol. Supportive clinical findings include the fact that patients in emergency departments who demonstrate a blunted response to salbutamol are more likely to benefit from (R)-salbutamol than rac-salbutamol, and resistance to salbutamol appears to be a contributory mechanism in rapid asthma deaths. More effort should therefore be applied to investigating potential enantiospecific effects of LABAs on safety, specifically bronchoprotection. Safety studies directly assessing the effects of LABA (S)-enantiomers on BHR are long overdue.

Readability and Suitability of COPD Consumer Information

BACKGROUND

Information leaflets have been shown to positively or negatively impact adherence, depending on their content. The objective of this study was to perform an appraisal of the consumer information provided in COPD inhaler monographs.

METHODS

COPD inhalers were identified from the Health Canada Drug Product Database. Medication information and instructions for inhaler use were analyzed for readability by seven formulas, with an acceptability threshold of grades 6-8. Three researchers rated suitability using a modified Suitability Assessment of Materials (SAM) tool and assessed leaflets for explicit warnings.

RESULTS

Twenty-six inhalers with a COPD indication were evaluated. Medication information sections were rated as "difficult to read" or "hard," and 85% (22/26) had a reading level above grade 8. The instructions for inhaler use were rated as "easy" or "fairly easy" to read and 63% (16/26) met the threshold by all formulas. While all leaflets achieved superior suitability ratings, extreme warnings included risk of premature death (n = 12), risks of serious injury (n = 26), serious interactions (n = 26), and statements that convey a serious consequence to therapy (n = 26).

CONCLUSION

While COPD information leaflets in Canada performed well in terms of readability and suitability, overemphasis on side effects, warnings, and precautions may contribute to patient fear and nonadherence.

Evaluation of AMSTAR to assess the methodological quality of systematic reviews in overviews of reviews of healthcare interventions

BACKGROUND

Overviews of reviews (overviews) compile information from multiple systematic reviews (SRs) to provide a single synthesis of relevant evidence for decision-making. It is recommended that authors assess and report the methodological quality of SRs in overviews-for example, using A MeaSurement Tool to Assess systematic Reviews (AMSTAR). Currently, there is variation in whether and how overview authors assess and report SR quality, and limited guidance is available. Our objectives were to: examine methodological considerations involved in using AMSTAR to assess the quality of Cochrane and non-Cochrane SRs in overviews of healthcare interventions; identify challenges (and develop potential decision rules) when using AMSTAR in overviews; and examine the potential impact of considering methodological quality when making inclusion decisions in overviews.

METHODS

We selected seven overviews of healthcare interventions and included all SRs meeting each overview's inclusion criteria. For each SR, two reviewers independently conducted AMSTAR assessments with consensus and discussed challenges encountered. We also examined the correlation between AMSTAR assessments and SR results/conclusions.

RESULTS

Ninety-five SRs were included (30 Cochrane, 65 non-Cochrane). Mean AMSTAR assessments (9.6/11 vs. 5.5/11; p < 0.001) and inter-rater reliability (AC1 statistic: 0.84 vs. 0.69; "almost perfect" vs. "substantial" using the Landis & Koch criteria) were higher for Cochrane compared to non-Cochrane SRs. Four challenges were identified when applying AMSTAR in overviews: the scope of the SRs and overviews often differed; SRs examining similar topics sometimes made different methodological decisions; reporting of non-Cochrane SRs was sometimes poor; and some non-Cochrane SRs included other SRs as well as primary studies. Decision rules were developed to address each challenge. We found no evidence that AMSTAR assessments were correlated with SR results/conclusions.

CONCLUSIONS

Results indicate that the AMSTAR tool can be used successfully in overviews that include Cochrane and non-Cochrane SRs, though decision rules may be useful to circumvent common challenges. Findings support existing recommendations that quality assessments of SRs in overviews be conducted independently, in duplicate, with a process for consensus. Results also suggest that using methodological quality to guide inclusion decisions (e.g., to exclude poorly conducted and reported SRs) may not introduce bias into the overview process.

What guidance is available for researchers conducting overviews of reviews of healthcare interventions? A scoping review and qualitative metasummary

BACKGROUND

Overviews of reviews (overviews) compile data from multiple systematic reviews to provide a single synthesis of relevant evidence for decision-making. Despite their increasing popularity, there is limited methodological guidance available for researchers wishing to conduct overviews. The objective of this scoping review is to identify and collate all published and unpublished documents containing guidance for conducting overviews examining the efficacy, effectiveness, and/or safety of healthcare interventions. Our aims were to provide a map of existing guidance documents; identify similarities, differences, and gaps in the guidance contained within these documents; and identify common challenges involved in conducting overviews.

METHODS

We conducted an iterative and extensive search to ensure breadth and comprehensiveness of coverage. The search involved reference tracking, database and web searches (MEDLINE, EMBASE, DARE, Scopus, Cochrane Methods Studies Database, Google Scholar), handsearching of websites and conference proceedings, and contacting overview producers. Relevant guidance statements and challenges encountered were extracted, edited, grouped, abstracted, and presented using a qualitative metasummary approach.

RESULTS

We identified 52 guidance documents produced by 19 research groups. Relatively consistent guidance was available for the first stages of the overview process (deciding when and why to conduct an overview, specifying the scope, and searching for and including systematic reviews). In contrast, there was limited or conflicting guidance for the latter stages of the overview process (quality assessment of systematic reviews and their primary studies, collecting and analyzing data, and assessing quality of evidence), and many of the challenges identified were also related to these stages. An additional, overarching challenge identified was that overviews are limited by the methods, reporting, and coverage of their included systematic reviews.

CONCLUSIONS

This compilation of methodological guidance for conducting overviews of healthcare interventions will facilitate the production of future overviews and can help authors address key challenges they are likely to encounter. The results of this project have been used to identify areas where future methodological research is required to generate empirical evidence for overview methods. Additionally, these results have been used to update the chapter on overviews in the next edition of the Cochrane Handbook for Systematic Reviews of Interventions.

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.

Inappropriate asthma therapy-a tale of two countries: a parallel population-based cohort study

Against recurrent controversies around the safety of short- and long-acting β₂-agonists (SABA and LABA), and the National Review of Asthma Deaths inquiry in the United Kingdom, we investigated the prevalence of inappropriate therapy in asthma. Our study aimed to determine the prevalence of inappropriate use of asthma therapy in the United Kingdom and in France. Two interval, parallel, population-based cohorts (2007 and 2013) were developed in each country by using the UK OPCRD and the French EGB databases. Patients aged 6-40 years were studied over the 12-month period following inclusion, regarding overuse (⩾12 units) of SABA, use of LABA without inhaled corticosteroids (ICS) and ⩾2-fold higher use of LABA compared with that of ICS. Overall, 39,743 UK and 4,910 French patients were included in 2007, and 14,036 and 5,657 patients, respectively, were included in 2013. UK adults were more frequently exposed to SABA overuse compared with those in France in both periods, with an upward trend in the United Kingdom (P<0.05). In 2013, LABA use without ICS occurred in 0.1% and 1.5% of United Kingdom and French adults, respectively. Unbalanced use of LABA relative to ICS became marginal in both countries in 2013. Inappropriate use of therapy was less marked, but present, in children. Inappropriate therapy remains a common issue in asthma. Based on our figures, it may be estimated that >210,000 British and >190,000 French asthmatics aged 6-40 years were inappropriately treated in 2013.

Pharmacotherapy in the management of asthma in the elderly: a review of clinical studies

Asthma in the elderly is a disease with emerging concern. Despite some recent advances in our understanding of epidemiology and pathophysiology, there is a considerable lack of clinical evidence specific to elderly patients. Currently available high quality clinical evidence has been mostly obtained from younger adults, but rarely from elderly patients. Under-representation of elderly patients in previous randomized trials may have been due to being, old age, or having comorbidities. Thus, a question may be raised whether current clinical evidence could be well generalized into elderly patients. Further clinical trials should address clinical issues raised in elderly population. In this review, we aimed to overview the efficacy and safety of pharmacological management, and also to summarize the literature relevant to elderly asthma.

Long-Acting Beta Agonists Enhance Allergic Airway Disease

Asthma is one of the most common of medical illnesses and is treated in part by drugs that activate the beta-2-adrenoceptor (β₂-AR) to dilate obstructed airways. Such drugs include long acting beta agonists (LABAs) that are paradoxically linked to excess asthma-related mortality. Here we show that LABAs such as salmeterol and structurally related β₂-AR drugs such as formoterol and carvedilol, but not short-acting agonists (SABAs) such as albuterol, promote exaggerated asthma-like allergic airway disease and enhanced airway constriction in mice. We demonstrate that salmeterol aberrantly promotes activation of the allergic disease-related transcription factor signal transducer and activator of transcription 6 (STAT6) in multiple mouse and human cells. A novel inhibitor of STAT6, PM-242H, inhibited initiation of allergic disease induced by airway fungal challenge, reversed established allergic airway disease in mice, and blocked salmeterol-dependent enhanced allergic airway disease. Thus, structurally related β₂-AR ligands aberrantly activate STAT6 and promote allergic airway disease. This untoward pharmacological property likely explains adverse outcomes observed with LABAs, which may be overcome by agents that antagonize STAT6.

Agonist binding to β-adrenergic receptors on human airway epithelial cells inhibits migration and wound repair

Human airway epithelial cells express β-adrenergic receptors (β-ARs), which regulate mucociliary clearance by stimulating transepithelial anion transport and ciliary beat frequency. Previous studies using airway epithelial cells showed that stimulation with isoproterenol increased cell migration and wound repair by a cAMP-dependent mechanism. In the present study, impedance-sensing arrays were used to measure cell migration and epithelial restitution following wounding of confluent normal human bronchial epithelial (NHBE) and Calu-3 cells by electroporation. Stimulation with epinephrine or the β2-AR-selective agonist salbutamol significantly delayed wound closure and reduced the mean surface area of lamellipodia protruding into the wound. Treatment with the β-AR bias agonist carvedilol or isoetharine also produced a delay in epithelial restitution similar in magnitude to epinephrine and salbutamol. Measurements of extracellular signal-regulated kinase phosphorylation following salbutamol or carvedilol stimulation showed no significant change in the level of phosphorylation compared with untreated control cells. However, inhibition of protein phosphatase 2A activity completely blocked the delay in wound closure produced by β-AR agonists. In Calu-3 cells, where CFTR expression was inhibited by RNAi, salbutamol did not inhibit wound repair, suggesting that β-AR agonist stimulation and loss of CFTR function share a common pathway leading to inhibition of epithelial repair. Confocal images of the basal membrane of Calu-3 cells labeled with anti-β1-integrin (clone HUTS-4) antibody showed that treatment with epinephrine or carvedilol reduced the level of activated integrin in the membrane. These findings suggest that treatment with β-AR agonists delays airway epithelial repair by a G protein- and cAMP-independent mechanism involving protein phosphatase 2A and a reduction in β1-integrin activation in the basal membrane.

A summary of the new GINA strategy: a roadmap to asthma control

Over the past 20 years, the Global Initiative for Asthma (GINA) has regularly published and annually updated a global strategy for asthma management and prevention that has formed the basis for many national guidelines. However, uptake of existing guidelines is poor. A major revision of the GINA report was published in 2014, and updated in 2015, reflecting an evolving understanding of heterogeneous airways disease, a broader evidence base, increasing interest in targeted treatment, and evidence about effective implementation approaches. During development of the report, the clinical utility of recommendations and strategies for their practical implementation were considered in parallel with the scientific evidence.This article provides a summary of key changes in the GINA report, and their rationale. The changes include a revised asthma definition; tools for assessing symptom control and risk factors for adverse outcomes; expanded indications for inhaled corticosteroid therapy; a framework for targeted treatment based on phenotype, modifiable risk factors, patient preference, and practical issues; optimisation of medication effectiveness by addressing inhaler technique and adherence; revised recommendations about written asthma action plans; diagnosis and initial treatment of the asthma-chronic obstructive pulmonary disease overlap syndrome; diagnosis in wheezing pre-school children; and updated strategies for adaptation and implementation of GINA recommendations.

Stopping long-acting beta2-agonists (LABA) for adults with asthma well controlled by LABA and inhaled corticosteroids

BACKGROUND

Poorly controlled asthma often leads to preventable exacerbations that require additional medications, as well as unscheduled hospital and clinic visits.Long-acting beta2-agonists (LABA) are commonly given to adults with asthma whose symptoms are not well controlled by inhaled corticosteroids (ICS). US and UK regulators have issued warnings for LABA in asthma, and now recommend they be used "for the shortest duration of time required to achieve control of asthma symptoms and discontinued, if possible, once asthma control is achieved".

OBJECTIVES

To compare cessation of long-acting beta2-agonists (LABA) versus continued use of LABA/inhaled corticosteroids (LABA/ICS) for adults whose asthma is well controlled, and to determine whether stopping LABA:1. results in loss of asthma control or deterioration in quality of life;2. increases the likelihood of asthma attacks or 'exacerbations'; or3. increases or decreases the likelihood of serious adverse events of any cause.

SEARCH METHODS

We searched the Cochrane Airways Group Specialised Register (CAGR), www.ClinicalTrials.gov, www.who.int/ictrp/en/, reference lists of primary studies and existing reviews and manufacturers' trial registries (GlaxoSmithKline (GSK) and AstraZeneca). We searched all databases from their inception to April 2015, and we imposed no restriction on language of publication.

SELECTION CRITERIA

We looked for parallel randomised controlled trials (RCTs) of at least eight weeks' duration, in which adults whose asthma was well controlled by any dose of ICS+LABA combination therapy were randomly assigned to (1) step-down therapy to ICS alone versus (2) continuation of ICS and LABA.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened all records identified by the search strategy. We used an Excel extraction tool to manage searches, document reasons for inclusion and exclusion and extract descriptive and numerical data from trials meeting inclusion criteria.Prespecified primary outcomes were (1) exacerbations requiring oral steroids, (2) asthma control and (3) all-cause serious adverse events.

MAIN RESULTS

Six randomised, double-blind studies between 12 and 24 weeks' long met the inclusion criteria. Five studies contributed data to the meta-analysis, assigning 2781 people with stable asthma to the comparison of interest. The definition of stable asthma and inclusion criteria varied across studies, and Global Initiative for Asthma (GINA) criteria were not used. Risk of bias across studies was generally low, and most evidence was rated as moderate quality.Stopping LABA might increase the number of people having exacerbations and requiring oral corticosteroids (odds ratio (OR) 1.74, 95% confidence interval (CI) 0.83 to 3.65; participants = 1257; studies = 4), although the confidence intervals did not exclude the possibility that stopping LABA was beneficial; over 17 weeks, 19 people per 1000 who continued their LABA had an exacerbation, compared with 32 per 1000 when LABA were stopped (13 more per 1000, 95% CI 3 fewer to 46 more).People who stopped LABA had worse scores on the Asthma Control Questionnaire (mean difference (MD) 0.24, 95% CI 0.13 to 0.35; participants = 645; studies = 3) and on measures of asthma-related quality of life (standardised mean difference (SMD) 0.36, 95% CI 0.15 to 0.57; participants = 359; studies = 2) than those who continued LABA, but the effects were not clinically relevant.Too few events occurred for investigators to tell whether stopping LABA has a greater effect on serious adverse events compared with continuing LABA+ICS (OR 0.82, 95% CI 0.28 to 2.42; participants = 1342; studies = 5), and no study reported exacerbations requiring an emergency department visit or hospitalisation as a separate outcome. Stopping LABA may result in fewer adverse events of any kind compared with continuing, although the effect was not statistically significant (OR 0.83, 95% CI 0.66 to 1.05; participants = 1339; studies = 5), and stopping LABA made people more likely to withdraw from participation in research studies (OR 1.95, 95% CI 1.47 to 2.58; participants = 1352; studies = 5).

AUTHORS' CONCLUSIONS

This review suggests that stopping LABA in adults who have stable asthma while they are taking a combination of LABA and ICS inhalers may increase the likelihood of asthma exacerbations that require treatment with oral corticosteroids, but this is not certain. Stopping LABA may slightly reduce asthma control and quality of life, but evidence was insufficient to show whether this had an effect on important outcomes such as serious adverse events and exacerbations requiring hospital admission, and longer trials are warranted. Trialists should include patient-important outcomes such as asthma control and quality of life and should use validated measurement tools. Definitions of exacerbations should be provided.

Long-acting muscarinic antagonists (LAMA) added to inhaled corticosteroids (ICS) versus addition of long-acting beta2-agonists (LABA) for adults with asthma

BACKGROUND

Poorly controlled asthma and preventable exacerbations place a significant strain on healthcare, often requiring additional medications, hospital stays or treatment in the emergency department.Long-acting beta2-agonists (LABA) are the preferred add-on treatment for adults with asthma whose symptoms are not well controlled on inhaled corticosteroids (ICS), but have important safety concerns in asthma. Long-acting muscarinic antagonists (LAMA) have confirmed efficacy in chronic obstructive pulmonary disease and are now being considered as an alternative add-on therapy for people with uncontrolled asthma.

OBJECTIVES

To assess the efficacy and safety of adding a LAMA to ICS compared with adding a LABA for adults whose asthma is not well controlled on ICS alone.

SEARCH METHODS

We searched the Cochrane Airways Group's Specialised Register (CAGR) from inception to April 2015, and imposed no restriction on language of publication. We searched additional resources to pick up unpublished studies, including ClinicalTrials.gov, World Health Organization trials portal, reference lists of primary studies and existing reviews, and manufacturers' trial registries. The most recent search was conducted in April 2015.

SELECTION CRITERIA

We searched for parallel and cross-over RCTs in which adults whose asthma was not well controlled with ICS alone were randomised to receive LAMA add-on or LABA add-on for at least 12 weeks.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the electronic and additional searches and extracted data from study reports. We used Covidence for duplicate screening, extraction of study characteristics and numerical data, and risk of bias ratings.The pre-specified primary outcomes were exacerbations requiring oral corticosteroids (OCS), quality of life and serious adverse events.

MAIN RESULTS

We included eight studies meeting the inclusion criteria, but four double-blind, double-dummy studies of around 2000 people dominated the analyses. These four trials were between 14 and 24 weeks long, all comparing tiotropium (usually Respimat) with salmeterol on top of medium doses of ICS.Studies reporting exacerbations requiring OCS showed no difference between the two add-ons, but our confidence in the effect was low due to inconsistency between studies and because the confidence intervals (CI) included significant benefit of either treatment (odds ratio (OR) 1.05, 95% CI 0.50 to 2.18; 1753 participants; 3 studies); three more people per 1000 might have an exacerbation on LAMA, but the CIs ranged from 29 fewer to 61 more. Imprecision was also an issue for serious adverse events and exacerbations requiring hospital admission, rated low (serious adverse events) and very low quality (exacerbations requiring hospital admission), because there were so few events in the analyses.People taking LAMA scored slightly worse on two scales measuring quality of life (Asthma Quality of Life Questionnaire; AQLQ) and asthma control (Asthma Control Questionnaire; ACQ); the evidence was rated high quality but the effects were small and unlikely to be clinically significant (AQLQ: mean difference (MD) -0.12, 95% CI -0.18 to -0.05; 1745 participants; 1745; 4 studies; ACQ: MD 0.06, 95% CI 0.00 to 0.13; 1483 participants; 3 studies).There was some evidence to support small benefits of LAMA over LABA on lung function, including on our pre-specified preferred measure trough forced expiratory volume in one second (FEV1) (MD 0.05 L, 95% CI 0.01 to 0.09; 1745 participants, 4 studies). However, the effects on other measures varied, and it is not clear whether the magnitude of the differences were clinically significant.More people had adverse events on LAMA but the difference with LABA was not statistically significant.

AUTHORS' CONCLUSIONS

Direct evidence of LAMA versus LABA as add-on therapy is currently limited to studies of less than six months comparing tiotropium (Respimat) to salmeterol, and we do not know how they compare in terms of exacerbations and serious adverse events. There was moderate quality evidence that LAMAs show small benefits over LABA on some measures of lung function, and high quality evidence that LABAs are slightly better for quality of life, but the differences were all small. Given the much larger evidence base for LABA versus placebo for people whose asthma is not well controlled on ICS, the current evidence is not strong enough to say that LAMA can be substituted for LABA as add-on therapy.The results of this review, alongside pending results from related reviews assessing the use of LAMA in other clinical scenarios, will help to define the role of these drugs in asthma and it is important that they be updated as results from ongoing and planned trials emerge.

Stopping long-acting beta2-agonists (LABA) for children with asthma well controlled on LABA and inhaled corticosteroids

BACKGROUND

Asthma is the most common chronic medical condition among children and is one of the most common causes of hospitalisation and medical visits. Poorly controlled asthma often leads to preventable exacerbations that require additional medications, hospital stays, or treatment in the emergency department.Long-acting beta2-agonists (LABA) are the preferred add-on treatment for children with asthma whose symptoms are not well controlled on inhaled corticosteroids (ICS). The US Food and Drug Administration has issued a 'black box' warning for LABA in asthma, and now recommends that they be used "for the shortest duration of time required to achieve control of asthma symptoms and discontinued, if possible, once asthma control is achieved".

OBJECTIVES

To compare the effect on asthma control and adverse effects of stepping down to inhaled corticosteroids (ICS)-only therapy versus continuing ICS plus LABA in children whose asthma is well controlled on combined ICS and LABA therapy.

SEARCH METHODS

We searched the Cochrane Airways Group Specialised Register, and also searched www.ClinicalTrials.gov, www.who.int/ictrp/en/, reference lists of primary studies and existing reviews, and manufacturers' trial registries (GlaxoSmithKline and AstraZeneca). We searched all databases from their inception to the present, and imposed no restriction on language of publication. The most recent search was done in April 2015.

SELECTION CRITERIA

We looked for parallel randomised controlled trials of at least eight weeks' duration, available as published full text, abstract only, or unpublished data. We excluded studies including participants with other chronic respiratory comorbidities (for example bronchiectasis).We looked for studies in which children (18 years or younger) whose asthma was well controlled on any dose of ICS and LABA combination therapy were randomised to: a) step-down therapy to ICS alone or b) continued use of ICS and LABA.We included any dose of LABA (formoterol, salmeterol, vilanterol) and any dose of ICS (beclomethasone, budesonide, ciclesonide, mometasone, flunisolide, fluticasone propionate, fluticasone furoate, triamcinolone) delivered in a combination inhaler or in separate inhalers.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened all records identified in the searches. We used a data extraction tool in Microsoft Excel to manage searches and document reasons for inclusion and exclusion, and to extract descriptive and numerical data from trials meeting the inclusion criteria.The prespecified primary outcomes were exacerbations requiring oral steroids, asthma control, and all-cause serious adverse events.

MAIN RESULTS

Despite conducting extensive searches of electronic databases, trial registries and manufacturers' websites we identified no trials matching the inclusion criteria.After removing duplicates, we screened 1031 abstracts, and assessed 43 full-text articles for inclusion. We identified several adult studies, which will be summarised in a separate review (Ahmad 2014). The most common reasons for exclusion after viewing full texts were 'wrong comparison' (n = 22) and 'adult population' (n = 18).Some adult studies recruited adolescents from age 15, but none reported data separately for those under 18.

AUTHORS' CONCLUSIONS

There is currently no evidence from randomised trials to inform the discontinuation of LABAs in children once asthma control is achieved with ICS plus LABA. It is disappointing that such an important issue has not been studied, and a randomised double-blind trial recruiting children who are controlled on ICS plus LABA is warranted. The study should be large enough to assess children of different ages, and to measure the important safety and efficacy outcomes suggested in this review over at least six months.The only randomised evidence for stopping LABA has been conducted in adults; it will be summarised in a separate review.