Efficacy and safety of inhaled formoterol 4.5 and 9 μg twice daily in Japanese and European COPD patients: phase III study results

Data Reproducibility and Effectiveness of Bronchodilators for Improving Physical Activity in COPD Patients

Increasing physical activity (PA) in patients with chronic obstructive pulmonary disease (COPD) is an important issue, however, the effect of bronchodilators on PA is still controversial. The indicators of PA, as measured by an accelerometer, can easily fluctuate based on several factors, which might cause inconsistent results. In this review, we listed the indicators of PA and the factors influencing the reproducibility of indicators of PA, and reviewed reports in which the effects of bronchodilators on PA were evaluated by an accelerometer. Then, we investigated the association between the processing of influencing factors and the effectiveness of bronchodilators for improving the PA of COPD patients. Fifteen reports were extracted using the PubMed database. In all seven reports in which adjustment was performed for at least two of four influencing factors (non-wear time, data from days with special behavior, environmental factors, and number of valid days required to obtain reproducible data), bronchodilators showed beneficial effects on PA. No adjustment was made for any of these factors in any of the four bronchodilator-ineffective reports. This suggests that the processing of influencing factors to secure reproducibility might affect the results regarding the effectiveness of bronchodilators for improving PA in COPD patients.

Long-Acting Bronchodilators for Chronic Obstructive Pulmonary Disease: Which One(S), How, and When?

Long-acting bronchodilators represent the mainstay of maintenance treatment of chronic obstructive pulmonary disease (COPD). This state-of-the-art review summarizes currently available data on the safety, efficacy, and clinical effectiveness of long-acting bronchodilators and describes their role in the management of COPD, as defined by current national and international guidelines. Data from extensive clinical trials and real-life studies have demonstrated that long-acting beta-2 agonists and long-acting muscarinic antagonists can safely reduce the frequency of exacerbations, alleviate symptoms, and improve quality of life, exercise tolerance, and lung function of patients with COPD. They are recommended as first-line maintenance treatment of COPD.

Fixed-Dose Combinations of Long-Acting Bronchodilators for the Management of COPD: Global and Asian Perspectives

Maintenance bronchodilator therapy with long-acting β-agonists (LABAs) and long-acting muscarinic antagonists (LAMAs) is the cornerstone treatment for patients with stable chronic obstructive pulmonary disease (COPD). Fixed-dose combinations (FDCs) of LABA/LAMA are recommended for the majority of symptomatic COPD patients by global guidelines; regional guidelines such as the Japanese and Korean guidelines also provide similar recommendations for the use of LABA/LAMA FDCs. This review comprehensively describes the latest clinical evidence from key studies on the efficacy and safety of four approved LABA/LAMA fixed-dose combinations: indacaterol/glycopyrronium, vilanterol/umeclidinium, formoterol/aclidinium, and olodaterol/tiotropium. Additionally, in this review we describe the rationale behind the use of LABA/LAMA FDC therapy, key findings from the preclinical and clinical trial evaluation of respective LABA and LAMA monocomponents, and the efficacy and safety of LABA/LAMA FDCs. Special emphasis is placed on the clinical evidence for the monocomponents and LABA/LAMA FDCs from the Asian population. This detailed overview of the efficacy and safety of LABA/LAMA FDCs in global and Asian COPD patients is envisaged to provide a better understanding of the benefits of these therapies and to inform healthcare providers and patients on their appropriate use.Funding: Novartis Pharma K.K.

Dual combination therapy versus long-acting bronchodilators alone for chronic obstructive pulmonary disease (COPD): a systematic review and network meta-analysis

BACKGROUND

Long-acting bronchodilators such as long-acting β-agonist (LABA), long-acting muscarinic antagonist (LAMA), and LABA/inhaled corticosteroid (ICS) combinations have been used in people with moderate to severe chronic obstructive pulmonary disease (COPD) to control symptoms such as dyspnoea and cough, and prevent exacerbations. A number of LABA/LAMA combinations are now available for clinical use in COPD. However, it is not clear which group of above mentioned inhalers is most effective or if any specific formulation works better than the others within the same group or class.

OBJECTIVES

To compare the efficacy and safety of available formulations from four different groups of inhalers (i.e. LABA/LAMA combination, LABA/ICS combination, LAMA and LABA) in people with moderate to severe COPD. The review will update previous systematic reviews on dual combination inhalers and long-acting bronchodilators to answer the questions described above using the strength of a network meta-analysis (NMA).

SEARCH METHODS

We identified studies from the Cochrane Airways Specialised Register, which contains several databases. We also conducted a search of ClinicalTrials.gov and manufacturers' websites. The most recent searches were conducted on 6 April 2018.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that recruited people aged 35 years or older with a diagnosis of COPD and a baseline forced expiratory volume in one second (FEV1) of less than 80% of predicted. We included studies of at least 12 weeks' duration including at least two active comparators from one of the four inhaler groups.

DATA COLLECTION AND ANALYSIS

We conducted NMAs using a Bayesian Markov chain Monte Carlo method. We considered a study as high risk if recruited participants had at least one COPD exacerbation within the 12 months before study entry and as low risk otherwise. Primary outcomes were COPD exacerbations (moderate to severe and severe), and secondary outcomes included symptom and quality-of-life scores, safety outcomes, and lung function. We collected data only for active comparators and did not consider placebo was not considered. We assumed a class/group effect when a fixed-class model fitted well. Otherwise we used a random-class model to assess intraclass/group differences. We supplemented the NMAs with pairwise meta-analyses.

MAIN RESULTS

We included a total of 101,311 participants from 99 studies (26 studies with 32,265 participants in the high-risk population and 73 studies with 69,046 participants in the low-risk population) in our systematic review. The median duration of studies was 52 weeks in the high-risk population and 26 weeks in the low-risk population (range 12 to 156 for both populations). We considered the quality of included studies generally to be good.The NMAs suggested that the LABA/LAMA combination was the highest ranked treatment group to reduce COPD exacerbations followed by LAMA in the both populations.There is evidence that the LABA/LAMA combination decreases moderate to severe exacerbations compared to LABA/ICS combination, LAMA, and LABA in the high-risk population (network hazard ratios (HRs) 0.86 (95% credible interval (CrI) 0.76 to 0.99), 0.87 (95% CrI 0.78 to 0.99), and 0.70 (95% CrI 0.61 to 0.8) respectively), and that LAMA decreases moderate to severe exacerbations compared to LABA in the high- and low-risk populations (network HR 0.80 (95% CrI 0.71 to 0.88) and 0.87 (95% CrI 0.78 to 0.97), respectively). There is evidence that the LABA/LAMA combination reduces severe exacerbations compared to LABA/ICS combination and LABA in the high-risk population (network HR 0.78 (95% CrI 0.64 to 0.93) and 0.64 (95% CrI 0.51 to 0.81), respectively).There was a general trend towards a greater improvement in symptom and quality-of-life scores with the combination therapies compared to monotherapies, and the combination therapies were generally ranked higher than monotherapies.The LABA/ICS combination was the lowest ranked in pneumonia serious adverse events (SAEs) in both populations. There is evidence that the LABA/ICS combination increases the odds of pneumonia compared to LAMA/LABA combination, LAMA and LABA (network ORs: 1.69 (95% CrI 1.20 to 2.44), 1.78 (95% CrI 1.33 to 2.39), and 1.50 (95% CrI 1.17 to 1.92) in the high-risk population and network or pairwise OR: 2.33 (95% CI 1.03 to 5.26), 2.02 (95% CrI 1.16 to 3.72), and 1.93 (95% CrI 1.29 to 3.22) in the low-risk population respectively). There were significant overlaps in the rank statistics in the other safety outcomes including mortality, total, COPD, and cardiac SAEs, and dropouts due to adverse events.None of the differences in lung function met a minimal clinically important difference criterion except for LABA/LAMA combination versus LABA in the high-risk population (network mean difference 0.13 L (95% CrI 0.10 to 0.15). The results of pairwise meta-analyses generally agreed with those of the NMAs. There is no evidence to suggest intraclass/group differences except for lung function at 12 months in the high-risk population.

AUTHORS' CONCLUSIONS

The LABA/LAMA combination was the highest ranked treatment group to reduce COPD exacerbations although there was some uncertainty in the results. LAMA containing inhalers may have an advantage over those without a LAMA for preventing COPD exacerbations based on the rank statistics. Combination therapies appear more effective than monotherapies for improving symptom and quality-of-life scores. ICS-containing inhalers are associated with an increased risk of pneumonia.Our most comprehensive review including intraclass/group comparisons, free combination therapies, 99 studies, and 20 outcomes for each high- and low-risk population summarises the current literature and could help with updating existing COPD guidelines.

Differences in physical activity according to mMRC grade in patients with COPD

BACKGROUND

Physical activity (PA) is impaired from the early stages of COPD, is associated with a worsening of disease prognosis, and causes COPD patients to restrict their daily activities in order to avoid breathlessness. The development of a simple tool to estimate physical activity level (PAL) could be useful for the management of COPD.

OBJECTIVES

We investigated the differences in PA according to the modified Medical Research Council (mMRC) grade in patients with COPD.

METHODS

A cross-sectional study was performed on stable outpatients with COPD. PA was measured for 2 weeks using a triaxial accelerometer, and dyspnea grade was evaluated in all patients using the mMRC scale.

RESULTS

Ninety-eight patients were recruited. Significant differences in PA duration were observed at all intensities according to the mMRC grade. Despite treatment with controller medications, 59.2% of COPD patients had low PAL, which was <1.5 metabolic equivalents multiplied by hour per day. COPD patients with an mMRC grade ≥2, which was the most balanced cutoff point in the receiver operating characteristic curve, showed a higher reduction rate of PAL (80.0% at mMRC grade 2, 71.4% at mMRC grade 3, and 100% at mMRC grade 4).

CONCLUSION

PA differed according to the mMRC grade, and mMRC grade ≥2 could predict a low PAL. Therefore, assessment of breathlessness by the mMRC questionnaire would be useful to stratify the risks of reduced PA in COPD.

Long-term outcomes in chronic obstructive pulmonary disease patients: exploring the effects of inhalatory devices and their influence on the outcome

PURPOSE

Numerous systematic reviews have examined the outcomes in patients with chronic obstructive pulmonary disease managed with different therapeutic strategies. However, no such studies have specifically focused on the effect of inhalation devices.

METHODS

A standard PubMed search was carried out in which we identified all randomized placebo-controlled trials conducted in patients with moderate-to-severe or severe chronic obstructive pulmonary disease. The clinical end points were exacerbations rate, incidence of pneumonia, and mortality. Meta-regression was employed to assess the effect of the device. For the incidence of exacerbations, an equivalence analysis was also carried out.

RESULTS

A total of 37 studies were analyzed. Four different devices were used across these trials (Respimat(®), HandiHaler(®), Diskus, and Turbuhaler(®)). Our meta-regression analysis failed to show any significant difference between devices with regard to exacerbation rate. Equivalence was shown for some comparisons (HandiHaler(®) vs Respimat(®)), but not for others. In analyzing mortality, Respimat(®) was shown to worsen this end point in comparison with Turbuhaler(®) and HandiHaler(®). Moreover, Turbuhaler(®) showed a protective effect over Diskus in the incidence of pneumonia.

CONCLUSION

The results of our analysis represent the first attempt to explore the effect of the type of device on long-term outcomes. One important limitation was that most drugs were associated with one particular device, and so the effects of drugs and devices could not be reliably differentiated from one another.

Inhaled Long-Acting β2-Agonists Do Not Increase Fatal Cardiovascular Adverse Events in COPD: A Meta-Analysis

BACKGROUND

The cardiovascular safety of inhaled long-acting β2-agonists (LABAs) in patients with chronic obstructive pulmonary disease (COPD) is a controversial problem. Certain studies have suggested that inhaled LABAs lead to an increased risk of cardiovascular events in patients with COPD. This meta-analysis aimed to assess the cardiovascular safety of inhaled LABAs in COPD.

METHODS

A meta-analysis of randomized, double-blind, parallel-group, placebo-controlled trials for LABA treatment of COPD with at least 3 months of follow-up was performed. The fixed-effects model was used to evaluate the effects of LABAs on fatal cardiovascular adverse events. Adverse events were collected for each trial, and the relative risk (RR) and 95% confidence intervals (CI) for LABA/placebo were estimated.

RESULTS

There were 24 trials included in this meta-analysis. Compared with placebo, inhaled LABAs significantly decreased fatal cardiovascular adverse events in COPD patients (RR 0.65, 95% CI 0.50 to 0.86, P = 0.002). In sensitivity analysis, there was still no increased risk of fatal cardiovascular events (RR 0.68, 95%CI 0.46 to 1.01, P = 0.06) after excluding the trial with the largest weight. Among the different types of LABAs, only salmeterol had a significant effect (RR 0.64, 95% CI 0.46 to 0.90). In subgroup analyses, inhaled LABAs were able to significantly decrease fatal cardiovascular events in long-term trials (RR 0.64, 95% CI 0.47 to 0.87) and in trials with severe COPD patients (RR 0.69, 95% CI 0.50 to 0.96).

CONCLUSION

Inhaled LABAs do not increase the risk of fatal cardiovascular events in COPD patients.

Long-acting inhaled therapy (beta-agonists, anticholinergics and steroids) for COPD: a network meta-analysis

BACKGROUND

Pharmacological therapy for chronic obstructive pulmonary disease (COPD) is aimed at relieving symptoms, improving quality of life and preventing or treating exacerbations.Treatment tends to begin with one inhaler, and additional therapies are introduced as necessary. For persistent or worsening symptoms, long-acting inhaled therapies taken once or twice daily are preferred over short-acting inhalers. Several Cochrane reviews have looked at the risks and benefits of specific long-acting inhaled therapies compared with placebo or other treatments. However for patients and clinicians, it is important to understand the merits of these treatments relative to each other, and whether a particular class of inhaled therapies is more beneficial than the others.

OBJECTIVES

To assess the efficacy of treatment options for patients whose chronic obstructive pulmonary disease cannot be controlled by short-acting therapies alone. The review will not look at combination therapies usually considered later in the course of the disease.As part of this network meta-analysis, we will address the following issues.1. How does long-term efficacy compare between different pharmacological treatments for COPD?2. Are there limitations in the current evidence base that may compromise the conclusions drawn by this network meta-analysis? If so, what are the implications for future research?

SEARCH METHODS

We identified randomised controlled trials (RCTs) in existing Cochrane reviews by searching the Cochrane Database of Systematic Reviews (CDSR). In addition, we ran a comprehensive citation search on the Cochrane Airways Group Register of trials (CAGR) and checked manufacturer websites and reference lists of other reviews. The most recent searches were conducted in September 2013.

SELECTION CRITERIA

We included parallel-group RCTs of at least 6 months' duration recruiting people with COPD. Studies were included if they compared any of the following treatments versus any other: long-acting beta2-agonists (LABAs; formoterol, indacaterol, salmeterol); long-acting muscarinic antagonists (LAMAs; aclidinium, glycopyrronium, tiotropium); inhaled corticosteroids (ICSs; budesonide, fluticasone, mometasone); combination long-acting beta2-agonist (LABA) and inhaled corticosteroid (LABA/ICS) (formoterol/budesonide, formoterol/mometasone, salmeterol/fluticasone); and placebo.

DATA COLLECTION AND ANALYSIS

We conducted a network meta-analysis using Markov chain Monte Carlo methods for two efficacy outcomes: St George's Respiratory Questionnaire (SGRQ) total score and trough forced expiratory volume in one second (FEV1). We modelled the relative effectiveness of any two treatments as a function of each treatment relative to the reference treatment (placebo). We assumed that treatment effects were similar within treatment classes (LAMA, LABA, ICS, LABA/ICS). We present estimates of class effects, variability between treatments within each class and individual treatment effects compared with every other.To justify the analyses, we assessed the trials for clinical and methodological transitivity across comparisons. We tested the robustness of our analyses by performing sensitivity analyses for lack of blinding and by considering six- and 12-month data separately.

MAIN RESULTS

We identified 71 RCTs randomly assigning 73,062 people with COPD to 184 treatment arms of interest. Trials were similar with regards to methodology, inclusion and exclusion criteria and key baseline characteristics. Participants were more often male, aged in their mid sixties, with FEV1 predicted normal between 40% and 50% and with substantial smoking histories (40+ pack-years). The risk of bias was generally low, although missing information made it hard to judge risk of selection bias and selective outcome reporting. Fixed effects were used for SGRQ analyses, and random effects for Trough FEV1 analyses, based on model fit statistics and deviance information criteria (DIC). SGRQ SGRQ data were available in 42 studies (n = 54,613). At six months, 39 pairwise comparisons were made between 18 treatments in 25 studies (n = 27,024). Combination LABA/ICS was the highest ranked intervention, with a mean improvement over placebo of -3.89 units at six months (95% credible interval (CrI) -4.70 to -2.97) and -3.60 at 12 months (95% CrI -4.63 to -2.34). LAMAs and LABAs were ranked second and third at six months, with mean differences of -2.63 (95% CrI -3.53 to -1.97) and -2.29 (95% CrI -3.18 to -1.53), respectively. Inhaled corticosteroids were ranked fourth (MD -2.00, 95% CrI -3.06 to -0.87). Class differences between LABA, LAMA and ICS were less prominent at 12 months. Indacaterol and aclidinium were ranked somewhat higher than other members of their classes, and formoterol 12 mcg, budesonide 400 mcg and formoterol/mometasone combination were ranked lower within their classes. There was considerable overlap in credible intervals and rankings for both classes and individual treatments. Trough FEV1 Trough FEV1 data were available in 46 studies (n = 47,409). At six months, 41 pairwise comparisons were made between 20 treatments in 31 studies (n = 29,271). As for SGRQ, combination LABA/ICS was the highest ranked class, with a mean improvement over placebo of 133.3 mL at six months (95% CrI 100.6 to 164.0) and slightly less at 12 months (mean difference (MD) 100, 95% CrI 55.5 to 140.1). LAMAs (MD 103.5, 95% CrI 81.8 to 124.9) and LABAs (MD 99.4, 95% CrI 72.0 to 127.8) showed roughly equivalent results at six months, and ICSs were the fourth ranked class (MD 65.4, 95% CrI 33.1 to 96.9). As with SGRQ, initial differences between classes were not so prominent at 12 months. Indacaterol and salmeterol/fluticasone were ranked slightly better than others in their class, and formoterol 12, aclidinium, budesonide and formoterol/budesonide combination were ranked lower within their classes. All credible intervals for individual rankings were wide.

AUTHORS' CONCLUSIONS

This network meta-analysis compares four different classes of long-acting inhalers for people with COPD who need more than short-acting bronchodilators. Quality of life and lung function were improved most on combination inhalers (LABA and ICS) and least on ICS alone at 6 and at 12 months. Overall LAMA and LABA inhalers had similar effects, particularly at 12 months. The network has demonstrated the benefit of ICS when added to LABA for these outcomes in participants who largely had an FEV1 that was less than 50% predicted, but the additional expense of combination inhalers and any potential for increased adverse events (which has been established by other reviews) require consideration. Our findings are in keeping with current National Institute for Health and Care Excellence (NICE) guidelines.

Budesonide/formoterol via Turbuhaler® versus formoterol via Turbuhaler® in patients with moderate to severe chronic obstructive pulmonary disease: phase III multinational study results

BACKGROUND AND OBJECTIVE

The efficacy and tolerability of budesonide/formoterol versus formoterol in patients with moderate to severe chronic obstructive pulmonary disease (COPD) was evaluated.

METHODS

In this randomized, double-blind, parallel-group, phase III study (NCT01069289), patients with moderate to severe COPD for ≥2 years received either budesonide/formoterol 160/4.5 μg two inhalations twice daily via Turbuhaler® or formoterol 4.5 μg two inhalations twice daily via Turbuhaler® for 12 weeks. Salbutamol was available as reliever medication. Primary outcome variable: change from baseline to average during treatment in pre-dose forced expiratory volume in 1 s (FEV1 ).

RESULTS

One thousand two hundred ninety-three patients were randomized (budesonide/formoterol n = 636; formoterol n = 657). Both budesonide/formoterol and formoterol increased pre-dose FEV1 versus baseline (improvements of 4.6% and 1.5% over baseline, respectively), with the increase from baseline being significantly greater with budesonide/formoterol versus formoterol (budesonide/formoterol:formoterol ratio 1.032; 95% confidence interval: 1.013-1.052; P = 0.0011). The budesonide/formoterol group had a significantly prolonged time to first exacerbation versus the formoterol group (hazard ratio: 0.679; 95% confidence interval: 0.507-0.909; P = 0.0094) and significantly greater improvements in many secondary outcome measures. Both treatments were well tolerated; the incidence and type of adverse events were similar: most commonly reported (budesonide/formoterol vs formoterol): COPD (8.0% vs 9.4%) and nasopharyngitis (5.5% vs 4.9%).

CONCLUSIONS

Budesonide/formoterol 160/4.5 μg two inhalations twice daily was effective and well tolerated in patients with moderate to severe COPD, offering benefits over formoterol alone in terms of improved lung function and reduced risk of exacerbation.

Long-acting beta2-agonists for chronic obstructive pulmonary disease

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a respiratory disease that causes progressive symptoms of breathlessness, cough and mucus build-up. It is the fourth or fifth most common cause of death worldwide and is associated with significant healthcare costs.Inhaled long-acting beta2-agonists (LABAs) are widely prescribed to manage the symptoms of COPD when short-acting agents alone are no longer sufficient. Twice-daily treatment with an inhaled LABA is aimed at relieving symptoms, improving exercise tolerance and quality of life, slowing decline and even improving lung function and preventing and treating exacerbations.

OBJECTIVES

To assess the effects of twice-daily long-acting beta2-agonists compared with placebo for patients with COPD on the basis of clinically important endpoints, primarily quality of life and COPD exacerbations.

SEARCH METHODS

We searched the Cochrane Airways Group trials register, ClinicalTrials.gov and manufacturers' websites in June 2013.

SELECTION CRITERIA

Parallel, randomised controlled trials (RCTs) recruiting populations of patients with chronic obstructive pulmonary disease. Studies were required to be at least 12 weeks in duration and designed to assess the safety and efficacy of a long-acting beta2-agonist against placebo.

DATA COLLECTION AND ANALYSIS

Data and characteristics were extracted independently by two review authors, and each study was assessed for potential sources of bias. Data for all outcomes were pooled and subgrouped by LABA agent (formoterol 12 μg, formoterol 24 μg and salmeterol 50 μg) and then were separately analysed by LABA agent and subgrouped by trial duration. Sensitivity analyses were conducted for the proportion of participants taking inhaled corticosteroids and for studies with high or uneven rates of attrition.

MAIN RESULTS

Twenty-six RCTs met the inclusion criteria, randomly assigning 14,939 people with COPD to receive twice-daily LABA or placebo. Study duration ranged from three months to three years; the median duration was six months. Participants were more often male with moderate to severe symptoms at randomisation; mean forced expiratory volume in 1 second (FEV1) was between 33% and 55% predicted normal in the studies, and mean St George's Respiratory Questionnaire score (SGRQ) ranged from 44 to 55 when reported.Moderate-quality evidence showed that LABA treatment improved quality of life on the SGRQ (mean difference (MD) -2.32, 95% confidence interval (CI) -3.09 to -1.54; I(2) = 50%; 17 trials including 11,397 people) and reduced the number of exacerbations requiring hospitalisation (odds ratio (OR) 0.73, 95% CI 0.56 to 0.95; I(2) = 10%; seven trials including 3804 people). In absolute terms, 18 fewer people per 1000 were hospitalised as the result of an exacerbation while receiving LABA therapy over a weighted mean of 7 months (95% CI 3 to 31 fewer). Scores were also improved on the Chronic Respiratory Disease Questionnaire (CRQ), and more people receiving LABA treatment showed clinically important improvement of at least four points on the SGRQ.The number of people who had exacerbations requiring a course of oral steroids or antibiotics was also lower among those taking LABA (52 fewer per 1000 treated over 8 months; 95% CI 24 to 78 fewer, moderate quality evidence).Mortality was low, and combined findings of all studies showed that LABA therapy did not significantly affect mortality (OR 0.90, 95% CI 0.75 to 1.08; I(2) = 21%; 23 trials including 14,079 people, moderate quality evidence). LABA therapy did not affect the rate of serious adverse events (OR 0.97, 95% CI 0.83 to 1.14; I(2) = 34%, moderate quality evidence), although there was significant unexplained heterogeneity, especially between the two formoterol doses.LABA therapy improved predose FEV1 by 73 mL more than placebo (95% CI 48 to 98; I(2) = 71%, low quality evidence), and people were more likely to withdraw from placebo than from LABA therapy (OR 0.74, 95% CI 0.69 to 0.80; I(2) = 0%). Higher rates of withdrawal in the placebo arm may reduce our confidence in some results, but the disparity is more likely to reduce the magnitude of difference between LABA and placebo than inflate the true effect; removing studies at highest risk of bias on the basis of high and unbalanced attrition did not change conclusions for the primary outcomes.

AUTHORS' CONCLUSIONS

Moderate-quality evidence from 26 studies showed that inhaled long-acting beta2-agonists are effective over the medium and long term for patients with moderate to severe COPD. Their use is associated with improved quality of life and reduced exacerbations, including those requiring hospitalisation. Overall, findings showed that inhaled LABAs did not significantly reduce mortality or serious adverse events.