The epidemiology, healthcare and societal burden and costs of asthma in the UK and its member nations: analyses of standalone and linked national databases

Treating severe paediatric asthma with mepolizumab or omalizumab: a protocol for the TREAT randomised non-inferiority trial

INTRODUCTION

A minority of school-aged children with asthma have persistent poor control and experience frequent asthma attacks despite maximal prescribed maintenance therapy. These children have higher morbidity and risk of death. The first add-on biologic therapy, omalizumab, a monoclonal antibody that blocks immunoglobulin (Ig)E, was licensed for children with severe asthma in 2005. While omalizumab is an effective treatment, non-response is common. A second biologic, mepolizumab which blocks interleukin 5 and targets eosinophilic inflammation, was licensed in 2018, but the licence was granted by extrapolation of adult clinical trial data to children. This non-inferiority (NI) trial will determine whether mepolizumab is as efficacious as omalizumab in reducing asthma attacks in children with severe therapy resistant asthma (STRA) and refractory difficult asthma (DA).

METHODS AND ANALYSIS

This is an ongoing multicentre 1:1 randomised NI open-label trial of mepolizumab and omalizumab. Up to 150 children and young people (CYP) aged 6-17 years with severe asthma will be recruited from specialist paediatric severe asthma centres in the UK. Prior to randomisation, children will be monitored for medication adherence for up to 16 weeks to determine STRA and refractory DA diagnoses. Current prescribing recommendations of serum IgE and blood eosinophils will not influence eligibility or enrolment. The primary outcome is the 52-week asthma attack rate. Bayesian analysis using clinician-elicited prior distributions will be used to calculate the posterior probability that mepolizumab is not inferior to omalizumab. Secondary outcomes include Composite Asthma Severity Index, Paediatric Asthma Quality of Life Questionnaire, lung function measures (forced expiratory volume in one second (FEV1), bronchodilator reversibility), fractional exhaled nitric oxide, Asthma Control Test (ACT), health outcomes EuroQol 5 Dimension (EQ-5D) and optimal serum IgE and blood eosinophil levels that may predict a response to therapy. These outcomes will be analysed in a frequentist framework using longitudinal models.

ETHICS AND DISSEMINATION

The study has been approved by the South Central-Berkshire Research Ethics Committee REC Number 19/SC/0634 and had Clinical Trials Authorisation from the Medicines and Healthcare Products Regulatory Agency (MHRA) (EudraCT 2019-004085-17). All parents/legal guardians will give informed consent for their child to participate in the trial, and CYP will give assent to participate. The results will be published in peer-reviewed journals, presented at international conferences and disseminated via our patient and public involvement partners.

TRIAL REGISTRATION NUMBER

ISRCTN12109108; EudraCT Number: 2019-004085-17.

Direct and indirect costs of paediatric asthma in the UK: a cost analysis

OBJECTIVE

To estimate the cost of paediatric asthma from a UK National Health Service (NHS) and societal perspective and explore determinants of these costs.

DESIGN

Cost analysis based on data from a large clinical trial between 2017 and 2019. Case report forms recorded healthcare resource use and productivity losses attributable to asthma over a 12-month period. These were combined with national unit cost data to generate estimates of health service and indirect costs.

SETTING

Asthma clinics in primary and secondary care in England and Scotland.

MAIN OUTCOME MEASURES

Cost per asthma attack stratified by highest level of care received. Total annual health service and indirect costs. Modelled effect of sex, age, severity, number of attacks and adherence on total annual costs.

RESULTS

Of 506 children included in the analysis, 252 experienced at least one attack. The mean (SD) cost per attack was £297 (806) (median £46, IQR 40-138) and the mean total annual cost to the NHS was £1086 (2504) (median £462, IQR 296-731). On average, children missed 6 days of school and their carers missed 13 hours of paid work, contributing to a mean annual indirect cost of £412 (879) (median £30, IQR 0-477). Health service costs increased significantly with number of attacks and participant age (>11 years). Indirect costs increased with asthma severity and number of attacks but were found to be lower in older children.

CONCLUSIONS

Paediatric asthma imparts a significant economic burden on the health service, families and society. Efforts to improve asthma control may generate significant cost savings.

TRIAL REGISTRATION NUMBER

ISRCTN 67875351.

Current technological advancement in asthma care

INTRODUCTION

Asthma is a common chronic respiratory disease affecting 262 million people globally, causing half a million deaths each year. Poor asthma outcomes are frequently due to non-adherence to medication, poor engagement with asthma services, and a lack of objective diagnostic tests. In recent years, technologies have been developed to improve diagnosis, monitoring, and care.

AREAS COVERED

Technology has impacted asthma care with the potential to improve patient outcomes, reduce healthcare costs, and provide personalized management. We focus on current evidence on home diagnostics and monitoring, remote asthma reviews, and digital smart inhalers. PubMed, Ovid/Embase, Cochrane Library, Scopus and Google Scholar were searched in November 2023 with no limit by year of publication.

EXPERT OPINION

Advanced diagnostic technologies have enabled early asthma detection and personalized treatment plans. Mobile applications and digital therapeutics empower patients to manage their condition and improve adherence to treatments. Telemedicine platforms and remote monitoring devices have the potential to streamline asthma care. AI algorithms can analyze patient data and predict exacerbations in proof-of-concept studies. Technology can potentially provide precision medicine to a wider patient group in the future, but further development is essential for implementation into routine care which in itself will be a major challenge.

Deploying an asthma dashboard to support quality improvement across a nationally representative sentinel network of 7.6 million people in England

Every year, there are ~100,000 hospital admissions for asthma in the UK, many of which are potentially preventable. Evidence suggests that carefully conceptualised and implemented audit and feedback (A&F) cycles have the potential to improve clinical outcomes for those with chronic conditions. We wanted to investigate the technical feasibility of developing a near-real time asthma dashboard to support A&F interventions for asthma management in primary care. We extracted cross-sectional data on asthma from 756 participating GP practices in the Oxford-Royal College of General Practitioners Research and Surveillance Centre (RCGP RSC) database in England comprising 7.6 million registered people. Summary indicators for a GP practice were compared to all participating RCGP RSC practices using practice-level data, for the week 6-12th-Mar-2023. A weekly, automated asthma dashboard with features that can support electronic-A&F cycles that compared key asthma indicators for a GP practice to RCGP RSC could be created ( https://tinyurl.com/3ydtrt85 ): 12-weeks-incidence 0.4% vs 0.4%, annual prevalence 6.1% vs 6.7%, inhaled relievers to preventer 1.2 vs 1.1, self-management plan given 83.4% vs 60.8%, annual reviews 36.8% vs 57.3%, prednisolone prescriptions 2.0% vs 3.2%, influenza vaccination 56.6% vs 55.5%, pneumococcal vaccination ever (aged ≥65 years) 90.2% vs 84.1% and current smokers 14.9% vs 14.8%. Across the RCGP RSC, the rate of hospitalisations was 0.024%; comparative data had to be suppressed for the study practice because of small numbers. We have successfully created an automated near real-time asthma dashboard that can be used to support A&F initiatives to improve asthma care and outcomes in primary care.

Adverse respiratory outcomes among patients with resolved asthma: matched retrospective cohort study

BACKGROUND

Patients with asthma may have symptom remission leading to a primary care code of resolved asthma. Little is known about subsequent rates of exacerbations and respiratory tract infections (RTIs).

AIM

To assess the risk of adverse respiratory outcomes for people with resolved asthma compared with those with active asthma and without asthma.

DESIGN AND SETTING

This was a retrospective cohort study of patients aged >5 years, registered with a general practice in England contributing data to the Clinical Practice Research Datalink between January 2010 and December 2019.

METHOD

Patients with resolved asthma were matched to non-asthma controls and active asthma controls for age, sex, and practice. Negative binomial regression was used to estimate incidence rate ratios (IRRs) with 95% confidence intervals (CIs) for asthma exacerbations, RTIs, flu/pneumonia, and antibiotic prescriptions.

RESULTS

Cohorts included 16 023 patients (8720 (54.4%) females, mean age 37 years). Compared with the active asthma cohort, the resolved cohort had fewer hospital admissions (adjusted IRR 0.29, 95% CI = 0.27 to 0.32) and general practice consultations (adjusted IRR 0.05, 95% CI = 0.04 to 0.07) for asthma exacerbations. The resolved and non-asthma cohorts had similar rates of hospital admissions for RTIs or flu/pneumonia. However, the resolved cohort had significantly greater incidence of general practice consultations for lower RTIs (adjusted IRR 2.34, 95% CI = 2.08 to 2.64) and antibiotic prescriptions (adjusted IRR 1.37, 95% CI = 1.30 to 1.44).

CONCLUSION

Patients with resolved asthma had greater risk of general practice RTI and antibiotic prescription than the general population and may benefit from defined strategies for reassessing symptoms and reinitiating asthma therapy.

Post-hospitalisation asthma management in primary care: a retrospective cohort study

BACKGROUND

Clinical guidelines recommend that patients admitted to hospital for asthma attacks are reviewed in primary care following hospital discharge.

AIM

To evaluate asthma management in primary care following a hospital admission for asthma and its associations with patient characteristics.

DESIGN AND SETTING

A retrospective cohort study using English primary care data from the Clinical Practice Research Datalink Aurum database and linked Hospital Episode Statistics Admitted Patient Care data.

METHOD

Patients with asthma aged ≥5 years who had at least one asthma-related hospital admission from 1 January 2017 to 31 December 2019 were included. The primary outcome was a composite of any of the following delivered in primary care within 28 days from hospital discharge: asthma review, asthma management plan, asthma medication prescriptions, demonstration of inhaler technique, or smoking cessation counselling. The association between patient characteristics and delivery of clinical care was assessed using logistic regression.

RESULTS

The study included 17 457 patients. A total of 10 515 (60.2%) patients received the primary outcome within 28 days of hospital discharge. There were 2311 (13.2%) who received an asthma review, 1459 (8.4%) an asthma management plan, 9996 (57.3%) an asthma medication, 1500 (8.6%) a demonstration of inhaler technique, and 52 (1.2% of smokers) had smoking cessation counselling. Patients from Black ethnic minority groups received less of this care (27%-54% lower odds, depending on age). However, short-acting bronchodilator prescriptions in the previous year were associated with an increased likelihood of the primary outcome.

CONCLUSION

A significant proportion of patients do not receive timely follow-up in primary care following asthma-related admissions to hospital, particularly among Black ethnic minority groups.

Expert consensus on oral corticosteroids stewardship for the treatment of severe asthma in the Middle East and Africa

In the Middle East and Africa (MEA) region, overuse of oral corticosteroids (OCS) for asthma management, both as burst and maintenance therapy, poses a significant challenge. Gaps in knowledge regarding the need to taper OCS in patients with severe asthma and the use of OCS in comorbid conditions have been noted. OCS stewardship can help attain optimal and effective OCS tapering along with reducing OCS overuse and over-reliance. In this paper, we discuss current practices regarding the use of OCS in asthma, globally and in the MEA region. Expert recommendations for achieving OCS stewardship in the MEA region have also been presented. Regional experts recommend increasing awareness among patients about the consequences of OCS overuse, engaging community pharmacists, and educating primary healthcare professionals about the benefits of prompt appropriate referral. Innovative local referral tools like ReferID can be utilized to refer patients with asthma to specialist care. The experts also endorse a multidisciplinary team approach and accelerating access to newer medicines like biologics to implement OCS stewardship and optimize asthma care in the MEA region.

Long-term health conditions and UK labour market outcomes during the COVID-19 pandemic

BACKGROUND

Long-term health conditions can affect labour market outcomes. COVID-19 may have increased labour market inequalities, e.g. due to restricted opportunities for clinically vulnerable people. Evaluating COVID-19's impact could help target support.

AIM

To quantify the effect of several long-term conditions on UK labour market outcomes during the COVID-19 pandemic and compare them to pre-pandemic outcomes.

METHODS

The Understanding Society COVID-19 survey collected responses from around 20,000 UK residents in nine waves from April 2020-September 2021. Participants employed in January/February 2020 with a variety of long-term conditions were matched with people without the condition but with similar baseline characteristics. Models estimated probability of employment, hours worked and earnings. We compared these results with results from a two-year pre-pandemic period. We also modelled probability of furlough and home-working frequency during COVID-19.

RESULTS

Most conditions (asthma, arthritis, emotional/nervous/psychiatric problems, vascular/pulmonary/liver conditions, epilepsy) were associated with reduced employment probability and/or hours worked during COVID-19, but not pre-pandemic. Furlough was more likely for people with pulmonary conditions. People with arthritis and cancer were slower to return to in-person working. Few effects were seen for earnings.

CONCLUSION

COVID-19 had a disproportionate impact on people with long-term conditions' labour market outcomes.

Acoustic biomarkers in asthma: a systematic review

OBJECTIVE

Current monitoring methods of asthma, such as peak expiratory flow testing, have important limitations. The emergence of automated acoustic sound analysis, capturing cough, wheeze, and inhaler use, offers a promising avenue for improving asthma diagnosis and monitoring. This systematic review evaluated the validity of acoustic biomarkers in supporting the diagnosis of asthma and its monitoring.

DATA SOURCES

A search was performed using two databases (PubMed and Embase) for all relevant studies published before November 2023.

STUDY SELECTION

27 studies were included for analysis. Eligible studies focused on acoustic signals as digital biomarkers in asthma, utilizing recording devices to register or analyze sound.

RESULTS

Various respiratory acoustic signal types were analyzed, with cough and wheeze being predominant. Data collection methods included smartphones, custom sensors and digital stethoscopes. Across all studies, automated acoustic algorithms achieved average accuracy of cough and wheeze detection of 88.7% (range: 61.0 - 100.0%) with a median of 92.0%. The sensitivity of sound detection ranged from 54.0 to 100.0%, with a median of 90.3%; specificity ranged from 67.0 to 99.7%, with a median of 95.0%. Moreover, 70.4% (19/27) studies had a risk of bias identified.

CONCLUSIONS

This systematic review establishes the promising role of acoustic biomarkers, particularly cough and wheeze, in supporting the diagnosis of asthma and monitoring. The evidence suggests the potential for clinical integration of acoustic biomarkers, emphasizing the need for further validation in larger, clinically-diverse populations.

Risk factors for asthma-related hospital and intensive care admissions in children, adolescents and adults: a cohort study using primary and secondary care data

BACKGROUND

Asthma remains a common cause of hospital admissions across the life course. We estimated the contribution of key risk factors to asthma-related hospital and intensive care unit (ICU) admissions in children, adolescents and adults.

METHODS

This was a UK-based cohort study using linked primary care (Clinical Practice Research Datalink Aurum) and secondary care (Hospital Episode Statistics Admitted Patient Care) data. Patients were eligible if they were aged 5 years and older and had been diagnosed with asthma. This included 90 989 children aged 5-11 years, 114 927 adolescents aged 12-17 years and 1 179 410 adults aged 18 years or older. The primary outcome was asthma-related hospital admissions from 1 January 2017 to 31 December 2019. The secondary outcome was asthma-related ICU admissions. Incidence rate ratios adjusted for demographic and clinical risk factors were estimated using negative binomial models. Population attributable fraction (PAF) was estimated for modifiable risk factors.

RESULTS

Younger age groups, females and those from ethnic minority and lower socioeconomic backgrounds had an increased risk of asthma-related hospital admissions. Increasing medication burden, including excessive use of short-acting bronchodilators, was also strongly associated with the primary outcome. Similar risk factors were observed for asthma-related ICU admissions. The key potentially modifiable or treatable risk factors were smoking in adolescents and adults (PAF 6.8%, 95% CI 0.9% to 12.3% and 4.3%, 95% CI 3.0% to 5.7%, respectively), and obesity (PAF 23.3%, 95% CI 20.5% to 26.1%), depression (11.1%, 95% CI 9.1% to 13.1%), gastro-oesophageal reflux disease (2.3%, 95% CI 1.2% to 3.4%), anxiety (2.0%, 95% CI 0.5% to 3.6%) and chronic rhinosinusitis (0.8%, 95% CI 0.3% to 1.3%) in adults.

CONCLUSIONS

There are significant sociodemographic inequalities in the rates of asthma-related hospital and ICU admissions. Treating age-specific modifiable risk factors should be considered an integral part of asthma management, which could potentially reduce the rate of avoidable hospital admissions.

Impact of sex on severe asthma: a cross-sectional retrospective analysis of UK primary and specialist care

INTRODUCTION

After puberty, females are more likely to develop asthma and in a more severe form than males. The associations between asthma and sex are complex with multiple intrinsic and external factors.

AIM

To evaluate the sex differences in the characteristics and treatment of patients with severe asthma (SA) in a real-world setting.

METHODS

Demographic, clinical and treatment characteristics for patients with SA in the UK Severe Asthma Registry (UKSAR) and Optimum Patient Care Research Database (OPCRD) were retrospectively analysed by sex using univariable and multivariable logistic regression analyses adjusted for year, age and hospital/practice.

RESULTS

3679 (60.9% female) patients from UKSAR and 18 369 patients (67.9% female) from OPCRD with SA were included. Females were more likely to be symptomatic with increased Asthma Control Questionnaire-6 (UKSAR adjusted OR (aOR) 1.14, 95% CI 1.09 to 1.18) and Royal College of Physicians-3 Question scores (OPCRD aOR 1.29, 95% CI 1.13 to 1.47). However, they had a higher forced expiratory volume in 1 second per cent (FEV1%) predicted (UKSAR 68.7% vs 64.8%, p<0.001) with no significant difference in peak expiratory flow. Type 2 biomarkers IgE (UKSAR 129 IU/mL vs 208 IU/mL, p<0.001) and FeNO (UKSAR 36ppb vs 46ppb, p<0.001) were lower in females with no significant difference in blood eosinophils or biological therapy. Females were less likely to be on maintenance oral corticosteroids (UKSAR aOR 0.86, 95% CI 0.75 to 0.99) but more likely to be obese (UKSAR aOR 1.67, 95% CI 145 to 1.93; OPCRD SA aOR 1.46, 95% CI 1.34 to 1.58).

CONCLUSIONS

Females had increased symptoms and were more likely to be obese despite higher FEV1% predicted and lower type 2 biomarkers with consistent and clinically important differences across both datasets.

High-Flow Humidified Oxygen as an Early Intervention in Children With Acute Severe Asthma: Protocol for a Feasibility Randomized Controlled Trial

BACKGROUND

Acute severe asthma (ASA) is a leading cause of hospital attendance in children. Standard first-line therapy consists of high-dose inhaled bronchodilators plus oral corticosteroids. Treatment for children who fail to respond to first-line therapy is problematic: the use of intravenous agents is inconsistent, and side effects are frequent. High-flow humidified oxygen (HiFlo) is widely used in respiratory conditions and is increasingly being used in ASA, but with little evidence for its effectiveness. A well-designed, adequately powered randomized controlled trial (RCT) of HiFlo therapy in ASA is urgently needed, and feasibility data are required to plan such an RCT. In this study, we describe the protocol for a feasibility study designed to fill this knowledge gap.

OBJECTIVE

This study aims to establish whether a full RCT of early HiFlo therapy in children with ASA can be conducted successfully and safely, to establish whether recruitment using deferred consent is practicable, and to define appropriate outcome measures and sample sizes for a definitive RCT. The underlying hypothesis is that early HiFlo therapy in ASA will reduce the need for more invasive treatments, allow faster recovery and discharge from hospital, and in both these ways reduce distress to children and their families.

METHODS

We conducted a feasibility RCT with deferred consent to assess the use of early HiFlo therapy in children aged 2 to 11 years with acute severe wheeze not responding to burst therapy (ie, high-dose inhaled salbutamol with or without ipratropium). Children with a Preschool Respiratory Assessment Measure score ≥5 after burst therapy were randomized to commence HiFlo therapy or follow standard care. The candidate primary outcomes assessed were treatment failure requiring escalation and time to meet hospital discharge criteria. Patient and parent experiences were also assessed using questionnaires and telephone interviews.

RESULTS

The trial was opened to recruitment in February 2020 but was paused for 15 months owing to the COVID-19 pandemic. The trial was reopened at the lead site in July 2021 and opened at the other 3 sites from August to December 2022. Recruitment was completed in June 2023.

CONCLUSIONS

This feasibility RCT of early HiFlo therapy in children with ASA recruited to the target despite major disturbances owing to the COVID-19 pandemic. The data are currently being analyzed and will be published separately.

TRIAL REGISTRATION

International Standard Randomised Controlled Trial Number Registry ISRCTN78297040; https://www.isrctn.com/ISRCTN78297040.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/54081.

Mast cell activation disrupts interactions between endothelial cells and pericytes during early life allergic asthma

Allergic asthma generally starts during early life and is linked to substantial tissue remodeling and lung dysfunction. Although angiogenesis is a feature of the disrupted airway, the impact of allergic asthma on the pulmonary microcirculation during early life is unknown. Here, using quantitative imaging in precision-cut lung slices (PCLSs), we report that exposure of neonatal mice to house dust mite (HDM) extract disrupts endothelial cell/pericyte interactions in adventitial areas. Central to the blood vessel structure, the loss of pericyte coverage was driven by mast cell (MC) proteases, such as tryptase, that can induce pericyte retraction and loss of the critical adhesion molecule N-cadherin. Furthermore, spatial transcriptomics of pediatric asthmatic endobronchial biopsies suggests intense vascular stress and remodeling linked with increased expression of MC activation pathways in regions enriched in blood vessels. These data provide previously unappreciated insights into the pathophysiology of allergic asthma with potential long-term vascular defects.

Immunogenicity of biologics used in the treatment of asthma

OBJECTIVE

Asthma is a major global disease affecting adults and children, which can lead to hospitalization and death due to breathing difficulties. Although targeted monoclonal antibody therapies have revolutionized treatment of severe asthma, some patients still fail to respond. Here we critically evaluate the literature on biologic therapy failure in asthma patients with particular reference to anti-drug antibody production, and subsequent loss of response, as the potential primary cause of drug failure in asthma patients.

RECENT FINDINGS

Encouragingly, asthma in most cases responds to treatment, including the use of an increasing number of biologic drugs in moderate to severe disease. This includes monoclonal antibody inhibitors of immunoglobulin E and cytokines, including interleukin 4, 5, or 13 and thymic stromal lymphopoietin. These limit mast cell and eosinophil activity that cause the symptomatic small airways obstruction and exacerbations.

SUMMARY

Despite humanization of the antibodies, it is evident that benralizumab; dupilumab; mepolizumab; omalizumab; reslizumab and tezepelumab all induce anti-drug antibodies to some extent. These can contribute to adverse events including infusion reactions, serum sickness, anaphylaxis and potentially disease activity due to loss of therapeutic function. Monitoring anti-drug antibodies (ADA) may allow prediction of future treatment-failure in some individuals allowing treatment cessation and switching therefore potentially limiting disease breakthrough.

Predictive Factors of Hospitalization and Emergency Visits Among Children With Asthma

Introduction A chronic diverse inflammatory disease, asthma affects millions of people worldwide. To control asthma, standardized care is essential. Children with asthma who receive appropriate care have lower emergency room (ER) visits and hospital stays as well as a higher quality of life than children who do not receive appropriate care. We aim to evaluate the predictive variables of hospitalization and ER visits in children with asthma. Methodology In 2022 and 2023, a cross-sectional descriptive study was carried out on children with asthma and their caregivers who were attending primary health care clinics in the eastern region of Saudi Arabia. We used the Childhood Asthma Control Test (C-ACT) to evaluate asthma control. A C-ACT score of less than 19 indicates uncontrolled childhood asthma. To investigate the relationships between the risk factors and the rate of ER visits and hospitalizations, we performed a multiple logistic descriptive analysis. Results In this study, 124 asthmatic children from primary health care centers matched the inclusion criteria. The majority of children had atopy, and their mean age was 10.8±3.4 years. Concerning the risk factors linked to ER visits and hospitalization, there is evidence that not following up with physicians, using more frequent and short-acting beta-agonists, exposure to smoke and household pets, and poor asthma control are linked to increased rates of both ER visits and hospitalizations. Conclusion Better asthma control in children and adolescents may be achieved by providing inexpensive asthma care services, more thorough parental and child education, and effective symptom management. These measures can help reduce exacerbations of asthma and the consequences that accompany them.

How have we measured trial outcomes of asthma attack treatment? A systematic review

Background

Asthma attacks are a common problem for people with asthma and are responsible for significant healthcare costs. There is interest in a precision medicine approach to treatment. However, the choice of trial outcome measures for asthma attack treatment is hampered by the absence of a consensus on suitability. We carried out a systematic review to understand the characteristics of outcome measures used in randomised controlled trials of asthma attack treatment. Have randomised controlled trials of asthma attack treatment measured outcomes that are useful to patients and healthcare providers?

Methods

The protocol was registered on PROSPERO (CRD42022311479). We searched for randomised controlled trials comparing treatments for adults with asthma attacks, published in English between 1972 and 2022 on MEDLINE, Embase and Cochrane Library databases. We recorded the outcome measures and study characteristics.

Results

We identified 208 eligible randomised controlled trials from 35 countries. Trials ranged from 12 to 1109 participants, with a median of 60. The most common settings were the emergency department (n=165) and hospital admission (n=33). Only 128 studies had primary and secondary outcomes defined clearly. In those that did, 73% of primary outcomes measured change in lung function or other physiological parameters over a short period (usually <24 h). Patient-reported and healthcare utilisation outcomes were the primary outcome in 27%.

Conclusions

Outcomes in randomised controlled trials of asthma attack treatment focus on short-term changes in lung function and may not capture patient-centred and economically important longer-term measures. More work is needed to investigate patient and other stakeholder preferences on core outcome sets.

Prevention Is Better than Cure: Impact of Allergen Immunotherapy on the Progression of Airway Disease

Allergen immunotherapy is highly effective for seasonal pollinosis. Three years of treatment results in long-term efficacy. This disease modification is accompanied by downregulation of allergen-specific Th2 responses and the induction of persistent specific IgG- and IgA-associated IgE-blocking activity. In children with seasonal rhinitis, both subcutaneous and sublingual pollen immunotherapy have been shown to reduce the development of asthma symptoms and asthma medication requirements. House dust mite tablet allergen immunotherapy has been shown to be effective for perennial mite-driven rhinitis in adults and children and may suppress asthma exacerbations, whereas its long-term efficacy has yet to be explored. The success of primary prevention of peanut allergy in childhood by introduction of peanut into the diet during infancy provides a strong rationale to explore whether primary prevention of inhalant allergies and asthma may also be possible. House dust mite allergy is a major risk factor for developing asthma. Preliminary data in at-risk children suggest that sublingual house dust mite immunotherapy initiated during infancy could reduce the onset of multiple allergen sensitizations and prevent the development of asthma at age 6 years. This possibility should now be explored in an adequately powered, prospectively randomized controlled trial.

Experience in Accessing Healthcare in Ethnic Minority Patients with Chronic Respiratory Diseases: A Qualitative Meta-Synthesis

BACKGROUND

Access to healthcare is part of every individual's human rights; however, many studies have illustrated that ethnic minority patients seem to be confronted with barriers when using healthcare services. Understanding how healthcare utilities are accessed from the perspective of patients and why healthcare disparities occur with patients from a minority background has the potential to improve health equality and care quality. This qualitative systematic review aims to gain insights into the experiences of people with chronic respiratory diseases (CRDs) from a minority background and explore factors contributing to their experiences in accessing healthcare to inform related health policy makers and healthcare providers.

METHODS

This systematic review complied with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses, where the Joanna Briggs Institute meta-aggregative instrument facilitated the qualitative synthesis. The study protocol was registered with PROSPERO (CRD42022346055). PubMed, Scopus, Web of Science, and CINAHL were the databases explored.

RESULTS

From the papers selected, 47 findings were derived from 10 included studies, and four synthesised findings were generated: (1) the relationship between patients and healthcare professionals affects the usage of healthcare services; (2) patients' perceptions and cultural beliefs affect their compliance with disease management; (3) personal behaviours affect the usage of healthcare services; and (4) health resource inequalities have an impact on accessing healthcare services.

CONCLUSIONS

This systematic review demonstrates that ethnic minorities with CRDs face inequalities when engaging in healthcare. The relationship between patients and clinicians impacting the use of healthcare is the most pivotal discovery, where not speaking the same language and being of a different race alongside the accompanying criticism and faith in facilities are key contributors to this effect. In addition, the thinking patterns of these marginalised groups may reflect their cultural upbringing and diminish their engagement with therapies. This paper has uncovered ways to attenuate inequalities amongst ethnic minorities in engaging with healthcare providers and provides insight into building effective equity-promoting interventions in healthcare systems. To overcome these disparities, coaching doctors to communicate better with minority cohorts could help such patients to be more comfortable in connecting with medical facilities.

Strong and graded associations between level of asthma severity and all-cause hospital care use and costs in the UK

BACKGROUND

Hospital admissions account for a large share of the healthcare costs incurred by people with asthma. We assessed the hospital care use and costs associated with asthma severity using the UK Biobank cohort and linked healthcare data.

METHODS

Adult participants with asthma at recruitment were classified using their prescription data into mild and moderate-to-severe asthma and matched separately to asthma-free controls by age, sex, ethnicity and location. The associations of asthma, by severity, with the annual number of all-cause hospital admissions, days spent in hospital and hospital costs were estimated over a 10-year follow-up period using three specifications of negative binomial regression models that differed according to the sociodemographic and clinical characteristics adjusted for.

RESULTS

Of the 25 031 participants with active asthma, 80% had mild asthma and 20% had moderate-to-severe asthma. Compared with participants with mild asthma, those with moderate-to-severe asthma were on average 2.7 years older, more likely to be current (13.7% vs 10.4%) or previous (40.2% vs 35.2%) smokers, to have a higher body mass index (BMI), and to be suffering from a variety of comorbid diseases. Following adjustments for age, sex, ethnicity and location, people with mild asthma experienced on average 36% more admissions (95% CI 28% to 40%), 43% more days in hospital (95% CI 35% to 51%) and 36% higher hospital costs (95% CI 31% to 41%) annually than asthma-free individuals, while people with moderate-to-severe asthma experienced excesses of 93% (95% CI 81% to 107%), 142% (95% CI 124% to 162%) and 98% (95% CI 88% to 108%), respectively. Further adjustments for socioeconomic deprivation, smoking status, BMI and comorbidities resulted in smaller though still highly significant positive associations, graded by severity, between asthma and hospital use and costs.

CONCLUSIONS

Strong graded associations are reported between asthma severity and the extent of hospital use and costs in the UK. These findings could inform future assessments of the value of asthma management interventions.

Maternal mental illness and child atopy: a UK population-based, primary care cohort study

BACKGROUND

The number of children exposed to maternal mental illness is rapidly increasing and little is known about the effects of maternal mental illness on childhood atopy.

AIM

To investigate the association between maternal mental illness and risk of atopy among offspring.

DESIGN AND SETTING

Retrospective cohort study using a UK primary care database (674 general practices).

METHOD

In total, 590 778 children (born 1 January 1993 to 30 November 2017) were followed until their 18th birthday, with 359 611 linked to their hospital records. Time-varying exposure was captured for common (depression and anxiety), serious (psychosis), addiction (alcohol and substance misuse), and other (eating and personality disorder) maternal mental illness from 6 months before pregnancy. Using Cox regression models, incidence rates of atopy were calculated and compared for the exposed and unexposed children in primary (asthma, eczema, allergic rhinitis, and food allergies) and secondary (asthma and food allergies) care, adjusted for maternal (age, atopy history, smoking, and antibiotic use), child (sex, ethnicity, and birth year/season), and area covariates (deprivation and region).

RESULTS

Children exposed to common maternal mental illness were at highest risk of developing asthma (adjusted hazard ratio [aHR] 1.17, 95% confidence interval [CI] = 1.15 to 1.20) and allergic rhinitis (aHR 1.17, 95% CI = 1.13 to 1.21), as well as a hospital admission for asthma (aHR 1.29, 95% CI = 1.20 to 1.38). Children exposed to addiction disorders were 9% less likely to develop eczema (aHR 0.91, 95% CI = 0.85 to 0.97) and 35% less likely to develop food allergies (aHR 0.65, 95% CI = 0.45 to 0.93).

CONCLUSION

The finding that risk of atopy varies by type of maternal mental illness prompts important aetiological questions. The link between common mental illness and childhood atopy requires GPs and policymakers to act and support vulnerable women to access preventive (for example, smoking cessation) services earlier.

Best step-up treatments for children with uncontrolled asthma: a systematic review and network meta-analysis of individual participant data

BACKGROUND

There is uncertainty about the best treatment option for children/adolescents with uncontrolled asthma despite inhaled corticosteroids (ICS) and international guidelines make different recommendations. We evaluated the pharmacological treatments to reduce asthma exacerbations and symptoms in uncontrolled patients age <18 years on ICS.

METHODS

We searched MEDLINE, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, Embase, Web of Science, National Institute for Health and Care Excellence Technology Appraisals, National Institute for Health and Care Research Health Technology Assessment series, World Health Organization International Clinical Trials Registry, conference abstracts and internal clinical trial registers (1 July 2014 to 5 May 2023) for randomised controlled trials of participants age <18 years with uncontrolled asthma on any ICS dose alone at screening. Studies before July 2014 were retrieved from previous systematic reviews/contact with authors. Patients had to be randomised to any dose of ICS alone or combined with long-acting β2-agonists (LABA) or combined with leukotriene receptor antagonists (LTRA), LTRA alone, theophylline or placebo. Primary outcomes were exacerbation and asthma control. The interventions evaluated were ICS (low/medium/high dose), ICS+LABA, ICS+LTRA, LTRA alone, theophylline and placebo.

RESULTS

Of the 4708 publications identified, 144 trials were eligible. Individual participant data were obtained from 29 trials and aggregate data were obtained from 19 trials. Compared with ICS Low, ICS Medium+LABA was associated with the lowest odds of exacerbation (OR 0.44, 95% credibility interval (95% CrI) 0.19-0.90) and with an increased forced expiratory volume in 1 s (mean difference 0.71, 95% CrI 0.35-1.06). Treatment with LTRA was the least preferred. No apparent differences were found for asthma control.

CONCLUSIONS

Uncontrolled children/adolescents on low-dose ICS should be recommended a change to medium-dose ICS+LABA to reduce the risk for exacerbation and improve lung function.

Recent trends in asthma diagnosis, preschool wheeze diagnosis and asthma exacerbations in English children and adolescents: a SABINA Jr study

BACKGROUND

Asthma-related burden remains poorly characterised in children in the UK. We quantified recent trends in asthma prevalence and burden in a UK population-based cohort (1‒17-year-olds).

METHODS

The Clinical Practice Research Datalink Aurum database (2008‒2018) was used to assess annual asthma incidence and prevalence in 1‒17-year-olds and preschool wheeze in 1‒5-year-olds, stratified by sex and age. During the same period, annual asthma exacerbation rates were assessed in those with either a diagnosis of preschool wheeze or asthma.

RESULTS

Annual asthma incidence rates decreased by 51% from 1403.4 (95% CI 1383.7 to 1423.2) in 2008 to 688.0 (95% CI 676.3 to 699.9) per 105 person-years (PYs) in 2018, with the most pronounced decrease observed in 1‒5-year olds (decreasing by 65%, from 2556.9 (95% CI 2509.8 to 2604.7) to 892.3 (95% CI 866.9 to 918.3) per 105 PYs). The corresponding decreases for the 6‒11- and 12‒17-year-olds were 36% (1139.9 (95% CI 1110.6 to 1169.7) to 739.9 (95% CI 720.5 to 759.8)) and 20% (572.3 (95% CI 550.4 to 594.9) to 459.5 (95% CI 442.9 to 476.4)) per 105 PYs, respectively. The incidence of preschool wheeze decreased over time and was slightly more pronounced in the 1‒3 year-olds than in the 4-year-olds. Prevalence of asthma and preschool wheeze also decreased over time, from 18.0% overall in 2008 to 10.2% in 2018 for asthma. Exacerbation rates increased over time from 1.33 (95% CI 1.31 to 1.35) per 10 PYs in 2008 to 1.81 (95% CI 1.78 to 1.83) per 10 PYs in 2018.

CONCLUSION

Paediatric asthma incidence decreased in the UK since 2008, particularly in 1-5-year-olds; this was accompanied by a decline in asthma prevalence. Preschool wheeze incidence also decreased in this age group. However, exacerbation rates have been increasing.

Use of feature importance statistics to accurately predict asthma attacks using machine learning: A cross-sectional cohort study of the US population

BACKGROUND

Asthma attacks are a major cause of morbidity and mortality in vulnerable populations, and identification of associations with asthma attacks is necessary to improve public awareness and the timely delivery of medical interventions.

OBJECTIVE

The study aimed to identify feature importance of factors associated with asthma in a representative population of US adults.

METHODS

A cross-sectional analysis was conducted using a modern, nationally representative cohort, the National Health and Nutrition Examination Surveys (NHANES 2017-2020). All adult patients greater than 18 years of age (total of 7,922 individuals) with information on asthma attacks were included in the study. Univariable regression was used to identify significant nutritional covariates to be included in a machine learning model and feature importance was reported. The acquisition and analysis of the data were authorized by the National Center for Health Statistics Ethics Review Board.

RESULTS

7,922 patients met the inclusion criteria in this study. The machine learning model had 55 out of a total of 680 features that were found to be significant on univariate analysis (P<0.0001 used). In the XGBoost model the model had an Area Under the Receiver Operator Characteristic Curve (AUROC) = 0.737, Sensitivity = 0.960, NPV = 0.967. The top five highest ranked features by gain, a measure of the percentage contribution of the covariate to the overall model prediction, were Octanoic Acid intake as a Saturated Fatty Acid (SFA) (gm) (Gain = 8.8%), Eosinophil percent (Gain = 7.9%), BMXHIP-Hip Circumference (cm) (Gain = 7.2%), BMXHT-standing height (cm) (Gain = 6.2%) and HS C-Reactive Protein (mg/L) (Gain 6.1%).

CONCLUSION

Machine Learning models can additionally offer feature importance and additional statistics to help identify associations with asthma attacks.

Association of body mass index with asthma occurrence and persistence in adolescents: A retrospective study of NHANES (2011-2018)

Objective

To investigate the association of body mass index (BMI) with asthma and analyze the risk factors of asthma persistence among overweight/obese adolescents and those with a high risk for obesity.

Methods

In this cross-sectional study, adolescents aged 11-17 years with complete general information and asthma diagnoses were selected from the National Health and Nutrition Examination Survey database. For adolescents without self-reported asthma, we performed matching according to age and sex at a case-to-control ratio of 1:3. Logistic regression analysis was employed to identify independent predictors of asthma occurrence followed by constructing a nomogram and comparing its efficacy to independent factors in predicting asthma occurrence. Besides, associations of BMI with asthma occurrence and persistence were evaluated. Finally, we obtained risk factors for asthma persistence in overweight/obese individuals and those at a high risk for obesity.

Results

Totally 753 adolescents with asthma and 2259 adolescents without asthma were included to analyze the occurrence of asthma. BMI and Hispanic Ethnicity were independent predictors of asthma occurrence and were included in nomogram construction. BMI had an efficiency comparable to that of the nomogram model in predicting asthma occurrence, which is superior to that of Hispanic Ethnicity. Of the 753 adolescents diagnosed with asthma, 464 were still diagnosed with asthma of at least a year's duration. Interestingly, BMI may have the ability to predict asthma persistence. Further, Hispanic Ethnicity and household income were significantly related to asthma occurrence among overweight/obese and high-risk obese individuals.

Conclusions

High BMI could independently predict increased asthma occurrence. Additionally, BMI may play an essential role in predicting asthma persistence. This study may help improve the diagnosis and reduce the occurrence of asthma.

Regular (up to 10 puffs 4-hourly) inhaled salbutamol should be prescribed at discharge after an asthma attack: myth or maxim?

Over the past 20 years, the concept of asthma weaning plans on discharge after an attack has crept into common practice, although the precise origin of these plans is unclear. High use of short-acting β2-agonists (SABAs) may result in tolerance to their bronchodilator effects, thus diminishing their efficacy, particularly when they are most needed at the time of an acute attack. Furthermore, key warning signs of a deterioration in asthma control may be masked and the weaning plan may encourage the over-use and over-reliance on SABAs. Side-effects from over-use may also occur, including lactic acidosis, downregulation of the β2-adrenoreceptor, increased allergen response and pro-inflammatory effects. The need for asthma education at discharge, a personal asthma action plan and vigilance about prescribing and ensuring adherence to maintenance therapy are definitely important. However, the current authors conclude that the benefit of prescribing regular salbutamol (up to 10 puffs every 4 h) at discharge after an acute asthma attack is a myth, and a very dangerous one.

Asthma hospitalisations and heat exposure in England: a case-crossover study during 2002-2019

BACKGROUND

Previous studies have reported an association between warm temperature and asthma hospitalisation. They have reported different sex-related and age-related vulnerabilities; nevertheless, little is known about how this effect has changed over time and how it varies in space. This study aims to evaluate the association between asthma hospitalisation and warm temperature and investigate vulnerabilities by age, sex, time and space.

METHODS

We retrieved individual-level data on summer asthma hospitalisation at high temporal (daily) and spatial (postcodes) resolutions during 2002-2019 in England from the NHS Digital. Daily mean temperature at 1 km×1 km resolution was retrieved from the UK Met Office. We focused on lag 0-3 days. We employed a case-crossover study design and fitted Bayesian hierarchical Poisson models accounting for possible confounders (rainfall, relative humidity, wind speed and national holidays).

RESULTS

After accounting for confounding, we found an increase of 1.11% (95% credible interval: 0.88% to 1.34%) in the asthma hospitalisation risk for every 1°C increase in the ambient summer temperature. The effect was highest for males aged 16-64 (2.10%, 1.59% to 2.61%) and during the early years of our analysis. We also found evidence of a decreasing linear trend of the effect over time. Populations in Yorkshire and the Humber and East and West Midlands were the most vulnerable.

CONCLUSION

This study provides evidence of an association between warm temperature and hospital admission for asthma. The effect has decreased over time with potential explanations including temporal differences in patterns of heat exposure, adaptive mechanisms, asthma management, lifestyle, comorbidities and occupation.

Understanding interventions delivered in the emergency department targeting improved asthma outcomes beyond the emergency department: an integrative review

OBJECTIVES

The emergency department (ED) represents a place and moment of opportunity to provide interventions to improve long-term asthma outcomes, but feasibility, effectiveness and mechanisms of impact are poorly understood. We aimed to review the existing literature on interventions that are delivered in the ED for adults and adolescents, targeting asthma outcomes beyond the ED, and to code the interventions according to theory used, and to understand the barriers and facilitators to their implementation.

METHODS

We systematically searched seven electronic databases and research registers, and manually searched reference lists of included studies and relevant reviews. Both quantitative and qualitative studies that reported on interventions delivered in the ED which aimed to improve asthma outcomes beyond management of the acute exacerbation, for adolescents or adults were included. Methodological quality was assessed using the Mixed Methods Appraisal Tool and informed study interpretation. Theory was coded using the Theoretical Domains Framework. Findings were summarised by narrative synthesis.

RESULTS

12 articles were included, representing 10 unique interventions, including educational and medication-based changes (6 randomised controlled trials and 4 non-randomised studies). Six trials reported statistically significant improvements in one or more outcome measures relating to long-term asthma control, including unscheduled healthcare, asthma control, asthma knowledge or quality of life. We identified limited use of theory in the intervention designs with only one intervention explicitly underpinned by theory. There was little reporting on facilitators or barriers, although brief interventions appeared more feasible.

CONCLUSION

The results of this review suggest that ED-based asthma interventions may be capable of improving long-term outcomes. However, there was significant variation in the range of interventions, reported outcomes and duration of follow-up. Future interventions would benefit from using behaviour change theory, such as constructs from the Theoretical Domains Framework.

PROSPERO REGISTRATION NUMBER

CRD 42020223058.

Non-randomised feasibility study testing a primary care intervention to promote engagement in an online health community for adults with troublesome asthma: protocol

INTRODUCTION

In the UK, approximately 4.3 million adults have asthma, with one-third experiencing poor asthma control, affecting their quality of life, and increasing their healthcare use. Interventions promoting emotional/behavioural self-management can improve asthma control and reduce comorbidities and mortality. Integration of online peer support into primary care services to foster self-management is a novel strategy. We aim to co-design and evaluate an intervention for primary care clinicians to promote engagement with an asthma online health community (OHC). Our protocol describes a 'survey leading to a trial' design as part of a mixed-methods, non-randomised feasibility study to test the feasibility and acceptability of the intervention.

METHODS AND ANALYSIS

Adults on the asthma registers of six London general practices (~3000 patients) will be invited to an online survey, via text messages. The survey will collect data on attitudes towards seeking online peer support, asthma control, anxiety, depression, quality of life, information on the network of people providing support with asthma and demographics. Regression analyses of the survey data will identify correlates/predictors of attitudes/receptiveness towards online peer support. Patients with troublesome asthma, who (in the survey) expressed interest in online peer support, will be invited to receive the intervention, aiming to reach a recruitment target of 50 patients. Intervention will involve a one-off, face-to-face consultation with a practice clinician to introduce online peer support, sign patients up to an established asthma OHC, and encourage OHC engagement. Outcome measures will be collected at baseline and 3 months post intervention and analysed with primary care and OHC engagement data. Recruitment, intervention uptake, retention, collection of outcomes, and OHC engagement will be assessed. Interviews with clinicians and patients will explore experiences of the intervention.

ETHICS AND DISSEMINATION

Ethical approval was obtained from a National Health Service Research Ethics Committee (reference: 22/NE/0182). Written consent will be obtained before intervention receipt and interview participation. Findings will be shared via dissemination to general practices, conference presentations and peer-reviewed publications.

TRIAL REGISTRATION NUMBER

NCT05829265.

Routine FEV1 measurement is essential in diagnosis and monitoring of childhood asthma: myth or maxim?

Childhood asthma is a common condition in children. This review describes the evidence from seven asthma guidelines for using spirometry in the diagnosis and monitoring of childhood asthma. All guidelines recommend spirometry as the primary test to be performed for diagnosing asthma in children aged >5 years. Spirometry is often normal in children with asthma. Guidelines are not consistent with respect to whether forced expiratory volume in 1 s (FEV1) or FEV1/forced vital capacity (FVC) should be measured, or their threshold for "abnormal" spirometry, and we describe the sensitivity and specificity for these different cut-offs. The role of spirometry in monitoring asthma is less clear in the guidelines, and some do not suggest spirometry should be done. There is no consensus on what spirometric measurement should be used, how often it should be measured and what is a minimum clinically important change in spirometry. The role of spirometry in diagnosing asthma is more clearly established when compared to its role in monitoring asthma. The potential of spirometry to aid decision making for asthma diagnosis and monitoring in children remains to be fully evaluated.

Educational aims

To provide knowledge of the commonly used guidelines for asthma diagnosis and management.To give insight into the opportunities and challenges in using spirometry to diagnose and monitor asthma in children.To provide an understanding of the precision of spirometry for diagnosing asthma.

Cost-Effectiveness of Fractional Exhaled Nitric Oxide Suppression Testing as an Adherence Screening Tool Among Patients With Difficult-to-Control Asthma

BACKGROUND

Approximately 50% of adults on long-term asthma medication are nonadherent. Current methods to detect nonadherence have had limited effect. Fractional exhaled nitric oxide suppression testing (FeNOSuppT) has demonstrated clinical effectiveness as an adherence screening tool to detect poor adherence to inhaled corticosteroids in difficult-to-control asthma prior to initiation of expensive biologic therapy.

OBJECTIVE

Estimate the cost effectiveness and budget impact of FeNOSuppT as a screen prior to the initiation of biologic therapy among U.S. adults with difficult-to-control asthma and high fractional exhaled nitric oxide (≥45 ppb).

METHODS

A decision tree simulated the progression of a cohort of patients over a 1-year time horizon into 1 of 3 states ([1] discharged from or [2] remain in specialist care; or [3] progress to biologics). Two strategies, with and without FeNOSuppT, were examined and the incremental net monetary benefit estimated using a discount rate of 3% and a willingness-to-pay threshold of $100,000 per quality-adjusted life year (QALY). Sensitivity analysis and a budget impact analysis were also undertaken.

RESULTS

In the baseline scenario, FeNOSuppT prior to the initiation of biologic therapy was associated with lower costs ($4,435/patient) and fewer QALYs (0.0023 QALY/patient) compared with no FeNOSuppT over 1 year and was considered cost effective (incremental net monetary benefit = $4,207). The FeNOSuppT was consistently found to be cost effective across a range of scenarios and in deterministic and probabilistic sensitivity analyses. Assuming differential levels of FeNOSuppT uptake (20%-100%), this was associated with budget savings ranging from USD $5 million to $27 million.

CONCLUSIONS

The FeNOSuppT is likely to be cost effective as a protocol-driven, objective, biomarker-based tool for identifying nonadherence in difficult-to-control asthma. This cost effectiveness is driven by cost savings from patients not progressing to expensive biologic therapy.

Implementation of a primary care asthma management quality improvement programme across 68 general practice sites

Despite national and international guidelines, asthma is frequently misdiagnosed, control is poor and unnecessary deaths are far too common. Large scale asthma management programme such as that undertaken in Finland, can improve asthma outcomes. A primary care asthma management quality improvement programme was developed with the support of the British Lung Foundation (now Asthma + Lung UK) and Optimum Patient Care (OPC) Limited. It was delivered and cascaded to all relevant staff at participating practices in three Clinical Commissioning Groups. The programme focussed on improving diagnostic accuracy, management of risk and control, patient self-management and overall asthma control. Patient data were extracted by OPC for the 12 months before (baseline) and after (outcome) the intervention. In the three CCGs, 68 GP practices participated in the programme. Uptake from practices was higher in the CCG that included asthma in its incentivised quality improvement programme. Asthma outcome data were successfully extracted from 64 practices caring for 673,593 patients. Primary outcome (Royal College of Physicians Three Questions [RCP3Q]) data were available in both the baseline and outcome periods for 10,328 patients in whom good asthma control (RCP3Q = 0) increased from 36.0% to 39.2% (p < 0.001) after the intervention. The odds ratio of reporting good asthma control following the intervention was 1.15 (95% CI 1.09-1.22), p < 0.0001. This asthma management programme produced modest but highly statistically significant improvements in asthma outcomes. Key lessons learnt from this small-scale implementation will enable the methodology to be improved to maximise benefit in a larger scale role out.

Asthma Exacerbations: The Genes Behind the Scenes

The clinical and socioeconomic burden of asthma exacerbations (AEs) constitutes a major public health problem. In the last 4 years, there has been an increase in ethnic diversity in candidate-gene and genome-wide association studies of AEs, which in the latter case led to the identification of novel genes and underlying pathobiological processes. Pharmacogenomics, admixture mapping analyses, and the combination of multiple "omics" layers have helped to prioritize genomic regions of interest and/or facilitated our understanding of the functional consequences of genetic variation. Nevertheless, the field still lags behind the genomics of asthma, where a vast compendium of genetic approaches has been used (eg, gene-environment nteractions, next-generation sequencing, and polygenic risk scores). Furthermore, the roles of the DNA methylome and histone modifications in AEs have received little attention, and microRNA findings remain to be validated in independent studies. Likewise, the most recent transcriptomic studies highlight the importance of the host-airway microbiome interaction in the modulation of risk of AEs. Leveraging -omics and deep-phenotyping data from subtypes or homogenous subgroups of patients will be crucial if we are to overcome the inherent heterogeneity of AEs, boost the identification of potential therapeutic targets, and implement precision medicine approaches to AEs in clinical practice.

IMPlementing IMProved Asthma self-management as RouTine (IMP2ART) in primary care: study protocol for a cluster randomised controlled implementation trial

BACKGROUND

Asthma is a common long-term condition and major public health problem. Supported self-management for asthma that includes a written personalised asthma action plan, supported by regular professional review, reduces unscheduled consultations and improves asthma outcomes and quality of life. However, despite unequivocal inter/national guideline recommendations, supported self-management is poorly implemented in practice. The IMPlementing IMProved Asthma self-management as RouTine (IMP²ART) implementation strategy has been developed to address this challenge. The aim of this implementation trial is to determine whether facilitated delivery of the IMP²ART strategy increases the provision of asthma action plans and reduces unscheduled care in the context of routine UK primary care.

METHODS

IMP²ART is a parallel group, cluster randomised controlled hybrid II implementation trial. One hundred forty-four general practices will be randomly assigned to either the IMP²ART implementation strategy or control group. Following a facilitation workshop, implementation group practices will receive organisational resources to help them prioritise supported self-management (including audit and feedback; an IMP²ART asthma review template), training for professionals and resources to support patients to self-manage their asthma. The control group will continue with usual asthma care. The primary clinical outcome is the between-group difference in unscheduled care in the second year after randomisation (i.e. between 12 and 24 months post-randomisation) assessed from routine data. Additionally, a primary implementation outcome of asthma action plan ownership at 12 months will be assessed by questionnaire to a random sub-group of people with asthma. Secondary outcomes include the number of asthma reviews conducted, prescribing outcomes (reliever medication and oral steroids), asthma symptom control, patients' confidence in self-management and professional support and resource use. A health economic analysis will assess cost-effectiveness, and a mixed methods process evaluation will explore implementation, fidelity and adaptation.

DISCUSSION

The evidence for supported asthma self-management is overwhelming. This study will add to the literature regarding strategies that can effectively implement supported self-management in primary care to reduce unscheduled consultations and improve asthma outcomes and quality of life.

TRIAL REGISTRATION

ISRCTN15448074. Registered on 2 December 2019.

Reducing oral steroid intolerability and drug costs for acute wheezers: A retrospective evaluation of a clinical management algorithm in a Pediatric Emergency Department

PROJECT AIM

To retrospectively evaluate a clinical management algorithm for acute wheezers in a UK Pediatric Emergency Department (PED).

OVERVIEW AND RATIONALE

Acute wheezing attacks are a leading cause of PED attendances and inpatient admissions. Prednisolone, a routine treatment, is intolerable in almost one-third of children, requiring repeated dosing, which may prolong length of stay (LOS). To address this problem, we: (1) developed an acute management algorithm (concise, single-sided flow-chart, instructing immediate management); (2) modified the OCS regime from prednisolone (1 mg/kg, 3-day course) to dexamethasone (600 then 300 mcg/kg); (3) and disseminated guidance regionally. Written information-handouts, e-mails, and posters-were followed-up with verbal reinforcement. We implemented the algorithm in 2017 and revised it further in 2018.

EVALUATION

In 2019, we retrospectively collected data on 100 acute wheeze attendances (those requiring OCS, aged 2-14), between October and December in 2016, 2017, and 2018 (n = 300), and assessed outcomes.

RESULTS

Over a 48-month period, we reduced OCS intolerability by 67.2% and OCS drug costs by 85.8% (saving £41,470.14), while not significantly influencing the other outcomes.

CONCLUSIONS

Reduced intolerability and substantial cost savings can be achieved by implementing a structured acute pediatric wheeze algorithm and modifying the OCS to single-dose dexamethasone (300 mcg/kg).

The Impact of Obesity in Saudi Arabia: Healthcare Resource Use and Costs Associated with Obesity-Related Complications

INTRODUCTION

Saudi Arabia has a high prevalence of obesity, which increases the risk of individuals experiencing multiple chronic complications. Only a few publications highlight the healthcare costs of obesity-related complications (ORCs) in Saudi Arabia.

METHODS

A micro-costing approach was used to estimate the healthcare costs associated with 10 ORCs. Experienced clinicians in public and private practice across different geographical regions in Saudi Arabia were asked to estimate healthcare resource use associated with each ORC, and estimated unit costs were obtained from hospital administrators. Estimated overall annual costs per patient were calculated as a weighted average of separate public and private sector costs.

RESULTS

Individuals in Saudi Arabia with any single ORC incurred overall average annual healthcare costs of 2165-7558 US dollars (USD). Heart failure, chronic kidney disease, dyslipidemia, and type 2 diabetes (T2D) were the most costly complications, mainly driven by monitoring and/or pharmacological treatment costs. In contrast, asthma, hypertension, and angina were the least costly complications. Costs in private healthcare were higher than in public healthcare; the largest differences (2359-2793 USD) were noted for dyslipidemia, T2D, and osteoarthritis, mainly explained by differences in pharmacological treatment costs.

CONCLUSIONS

These data suggest that ORCs result in a considerable financial burden to the healthcare system, and highlight the substantial cost savings that could be achieved by preventing or delaying the occurrence of ORCs in Saudi Arabia.

Potential for repurposing oral hypertension/diabetes drugs to decrease asthma risk in obesity

OBJECTIVE

Risk for asthma in the overweight/obese may be mediated by adiponectin and peroxisome proliferator activated receptor pathways and may be reduced by the use of oral drugs impacting these pathways, such as angiotensin converting enzyme inhibitors (ACE-I), thiazolidinediones (TZD), and angiotensin receptor blockers (ARB). Our study objective was to determine whether ACE-I, TZD, and/or ARB use in overweight/obese adults with diabetes mellitus and/or hypertension is associated with a lower risk for incident asthma.

METHODS

Using an existing cohort of American veterans, we performed a longitudinal data analysis over 15 years. Exposure was defined by the prescription pickup of ACE-I, TZD, and/or ARB for at least 4 weeks. The outcome, time until new-onset of clinician-diagnosed asthma, was studied using survival analysis. The propensity scoring method controlled for treatment selection bias.

RESULTS

2.83 million eligible veterans, including 77,278 with incident asthma, were studied. As compared to those unexposed, the use of ACE-I alone, TZD alone, or their combinations were each associated with decreased risk for incident asthma (hazard ratios of 0.88, 0.74, and 0.20, respectively; p < 0.001 for all analyses in the fully adjusted statistical models). TZD lowered the risk among racial/ethnic minority subjects more than among White participants (p < 0.001). On the other hand, ARB use alone or in combination with TZD was associated with a higher risk for incident asthma.

CONCLUSIONS

Use of ACE-I and/or TZD was associated with a lower risk for incident asthma in overweight/obese patients with diabetes mellitus and/or hypertension.

Peripheral blood eosinophilia in adult asthmatic patients and its association with the severity of asthma

BACKGROUND

Asthma is a diverse disease with various etiologic bases. Severe asthma can be associated with increased mortality, hospitalization, and decreased quality of life for asthma patients. High blood eosinophil counts were associated with severe asthma, but recent studies have failed to confirm this as a marker of severe asthma among adult asthma patients. As a result, the purpose of this study was to determine the association between the severity of asthma and high blood eosinophil count.

METHODOLOGY

A simple random sampling technique was used to select 291 asthmatic patients for an institution-based cross-sectional study. Socio-demographic, behavioral, and clinical characteristics were collected by using a pre-tested structured questionnaire. Four milliliters of venous blood were collected from asthmatic patients for complete blood count and peripheral morphology assessment. The eosinophil count was analyzed by the Unicel DxH 800 (Beckman Coulter, Ireland) analyzer. A statistical package for social science version 20 (SPSS) software was used to analyze the data. The non-parametric (Mann-Whitney U) test was used to compare the eosinophil count with different background variables. A binary logistic regression analysis was used to assess the factors associated with eosinophilia. A p-value less than 0.05 in multivariable logistic regression analysis was considered statistically significant.

RESULT

In this study, the overall magnitude of eosinophilia was 19.6% (95% CI = 14.8-24.1). Being admitted to the emergency department (AOR = 0.25; 95% CI: 0.09-0.69, p = 0.007) and being female (AOR = 0.49; 95% CI: 0.26-0.9, p = 0.025) were shown to have a statistically significant association with eosinophilia. Moreover, the absolute eosinophil count was significantly higher among asthmatic patients infected with intestinal parasitic infection (p < 0.045).

CONCLUSION

Being female and admission to the emergency department were negatively associated with eosinophilia. Lack of eosinophilia can be related to the low-T2 asthma phenotype. The absolute eosinophil counts were higher among intestinal parasite-infected patients. Therefore, different biomarkers will be considered for the proper diagnosis and management of adult asthma patients.

Economic Burden of Asthma in Northwest Iran

Background

The economic burden of asthma is a major public health concern. This study estimates the economic burden of asthma in Northwest of Iran.

Methods

A longitudinal study was conducted between 2017 and 2018 in Tabriz (Iran) using the Persian version of the Work Productivity and Activity Impairment (WPAI) questionnaire. Direct and indirect costs associated with asthma were estimated based on the societal perspective, prevalence-based approach, and bottom-up method. Annual indirect costs were estimated using the human capital (HC) method. The structural equation model was used to evaluate the relationship between costs, sex, and asthma severity.

Results

A total of 621 patients with asthma were enrolled in the study. Significant differences were found between female and male patients for the mean cost of radiology (P=0.006), laboratory (P=0.028), and diagnostic (P=0.017) tests at baseline, and for laboratory (P=0.012), and diagnostic (P=0.027) tests at one-year follow-up. The more severe asthma, the more significant the costs for annual physician office visits (P=0.040) and medications (P=0.013). As asthma severity increased, significantly higher expenditures were observed in women for days lost from work at baseline (P=0.009) and one-year follow-up (P=0.001), and in men for productivity loss at work due to impairment at baseline (P=0.045). A significant association between indirect costs and the cost of impairment-related lost productivity at work (β=3.29, P<0.001), and between severe asthma and indirect costs (β=32.36, P<0.001) was observed.

Conclusion

High costs are incurred by Iranian asthma patients, especially because of impairment-related productivity loss at work associated with asthma exacerbation.

Preferences for support in managing symptoms of an asthma flare-up: a pilot study of a discrete choice experiment

Objective: Information on the preferences of people with asthma for support in managing a flare-up can inform service design which may facilitate appropriate help-seeking. To date, little is known about support preferences for managing a flare-up. The aim of this study was to develop and pilot a discrete choice experiment (DCE) to elicit the preferences of people with asthma with regards to support in managing a flare-up.Methods: Steps in developing the DCE included identification and selection of attributes and levels of the support services, construction of choice tasks, experimental design, construction of DCE instrument, and pretest (n=16) and pilot (n=38) studies of the DCE instrument. A multinomial logit model was used to examine the strength and direction of the six attributes in the pilot study.Results: Our results indicate that from a patient perspective, having a healthcare professional that listens to their concerns was the most valued attribute of support in asthma flare-up management. The other features of support valued by participants were timely access to consultation, a healthcare professional with knowledge of their patient history, a specialist doctor and face-to-face communication. Having a written action plan was the least valued attribute.Conclusions: Our findings suggest patient preference for a model of support in managing their symptoms which includes timely, face-to-face access to a healthcare professional that knows them and listens to their concerns. The findings of the pilot study need to be verified with a larger sample and using models to account for preference heterogeneity.

Development of multiple reaction monitoring (MRM) assays to identify Brucella abortus proteins in the serum of humans and livestock

In the present study, a targeted multiple reaction monitoring-mass spectrometry (MRM-MS) approach was developed to screen and identify protein biomarkers for brucellosis in humans and livestock. The selection of proteotypic peptides was carried out by generating in silico tryptic peptides of the Brucella proteome. Using bioinformatics analysis, 30 synthetic peptides corresponding to 10 immunodominant Brucella abortus proteins were generated. MRM-MS assays for the accurate detection of these peptides were optimized using 117 serum samples of human and livestock stratified as clinically confirmed (45), suspected (62), and control (10). Using high throughput MRM assays, transitions for four peptides were identified in several clinically confirmed and suspected human and livestock serum samples. Of these, peptide NAIYDVVTR corresponding to B. abortus proteins: BruAb2_0537 was consistently detected in the clinically confirmed serum samples of both humans and livestock with 100% specificity. To conclude, a high throughput MRM-MS-based protocol for detecting endogenous B. abortus peptides in serum samples of humans and livestock was developed. The developed protocol will help design sensitive assays to accurately diagnose brucellosis in humans and livestock. The data associated with this study are deposited in Panorama Public (https://panoramaweb.org/rNOZCy.url with ProteomeXchange ID: PXD034407).

Novel multimorbidity clusters in people with eczema and asthma: a population-based cluster analysis

Eczema and asthma are allergic diseases and two of the commonest chronic conditions in high-income countries. Their co-existence with other allergic conditions is common, but little research exists on wider multimorbidity with these conditions. We set out to identify and compare clusters of multimorbidity in people with eczema or asthma and people without. Using routinely-collected primary care data from the U.K. Clinical Research Practice Datalink GOLD, we identified adults ever having eczema (or asthma), and comparison groups never having eczema (or asthma). We derived clusters of multimorbidity from hierarchical cluster analysis of Jaccard distances between pairs of diagnostic categories estimated from mixed-effects logistic regressions. We analysed 434,422 individuals with eczema (58% female, median age 47 years) and 1,333,281 individuals without (55% female, 47 years), and 517,712 individuals with asthma (53% female, 44 years) and 1,601,210 individuals without (53% female, 45 years). Age at first morbidity, sex and having eczema/asthma affected the scope of multimorbidity, with women, older age and eczema/asthma being associated with larger morbidity clusters. Injuries, digestive, nervous system and mental health disorders were more commonly seen in eczema and asthma than control clusters. People with eczema and asthma of all ages and both sexes may experience greater multimorbidity than people without eczema and asthma, including conditions not previously recognised as contributing to their disease burden. This work highlights areas where there is a critical need for research addressing the burden and drivers of multimorbidity in order to inform strategies to reduce poor health outcomes.

Patient views on asthma diagnosis and how a clinical decision support system could help: A qualitative study

INTRODUCTION

Making a diagnosis of asthma can be challenging for clinicians and patients. A clinical decision support system (CDSS) for use in primary care including a patient-facing mode, could change how information is shared between patients and healthcare professionals and improve the diagnostic process.

METHODS

Participants diagnosed with asthma within the last 5 years were recruited from general practices across four UK regions. In-depth interviews were used to explore patient experiences relating to their asthma diagnosis and to understand how a CDSS could be used to improve the diagnostic process for patients. Interviews were audio recorded, transcribed verbatim and analysed using a thematic approach.

RESULTS

Seventeen participants (12 female) undertook interviews, including 14 individuals and 3 parents of children with asthma. Being diagnosed with asthma was generally considered an uncertain process. Participants felt a lack of consultation time and poor communication affected their understanding of asthma and what to expect. Had the nature of asthma and the steps required to make a diagnosis been explained more clearly, patients felt their understanding and engagement in asthma self-management could have been improved. Participants considered that a CDSS could provide resources to support the diagnostic process, prompt dialogue, aid understanding and support shared decision-making.

CONCLUSION

Undergoing an asthma diagnosis was uncertain for patients if their ideas and concerns were not addressed by clinicians and were influenced by a lack of consultation time and limitations in communication. An asthma diagnosis CDSS could provide structure and an interface to prompt dialogue, provide visuals about asthma to aid understanding and encourage patient involvement.

PATIENT AND PUBLIC CONTRIBUTION

Prespecified semistructured interview topic guides (young person and adult versions) were developed by the research team and piloted with members of the Asthma UK Centre for Applied Research Patient and Public Involvement (PPI) group. Findings were regularly discussed within the research group and with PPI colleagues to aid the interpretation of data.

Airwave oscillometry and spirometry in children with asthma or wheeze

OBJECTIVE

Lung function testing is used in diagnosing asthma and assessing asthma control. Spirometry is most commonly used, but younger children can find performing this test challenging. Non-volitional tests such as airwave oscillometry (AOS) may be helpful in that population. We compared the success of spirometry and AOS in assessing bronchodilator responsiveness in children.

METHODS

AOS was conducted alongside routine lung function testing. Resistance at 5 Hz (R5), the difference between the resistance at 5 and 20 Hz (R5-20) and the area under the reactance curve (AX) were assessed. Patients between 5 and 16 years old attending clinic with wheeze or asthma were assessed. Patients performed AOS, followed by spirometry and were then given 400 µg salbutamol; the tests were repeated 15 minutes later.

RESULTS

Lung function testing was performed in 47 children of whom 46 (98%) and 32 (68%) performed acceptable baseline oscillometry and spirometry, respectively (p < 0.001). Children unable to perform acceptable spirometry were younger (7.35, range: 5.4-10.3 years) than those who could (10.4, range: 5.5-16.9 years), p < 0.001. The baseline z-scores of AOS R5 correlated with FEV₁ (r = 0.499, p = 0.004), FEF₇₅ (r = 0.617, p < 0.001), and FEV₁/FVC (r = 0.618, p < 0.001). There was a positive bronchodilator response assessed by spirometry (change in FEV₁ ≥ 12%) in eight children which corresponded to a change in R5 of 36% (range: 30%-50%) and a change in X5 of 39% (range: 15%-54%).

CONCLUSIONS

Oscillometry is a useful adjunct to spirometry in assessing young asthmatic children's lung function. The degree of airway obstruction, however, might affect the comparability of the results of the two techniques.

Practical approaches to the diagnosis of asthma in school-age children

INTRODUCTION

Asthma is a chronic airways disease characterized by episodes of wheeze, chest tightness, and evidence of reversible airflow obstruction. Symptoms are frequently triggered by exercise, exposure to aeroallergens, and respiratory viruses. It is the commonest non-communicable respiratory condition in children, affecting over 5.5 million children in the European Union alone. Both over- and under- diagnosis of asthma are common for several reasons.

AREAS COVERED

The diagnosis is frequently based on parental or patient reported non-specific symptoms alone. All major asthma guidelines now recommend the use of objective tests, including spirometry, bronchodilator reversibility testing, fraction of exhaled nitric oxide measurements and challenge testing to confirm the diagnosis. Recently, the European Respiratory Society published the first evidence-based international guidelines for diagnosing asthma in school-age children using objective measures. Major barriers to implementation in primary care and less well-resourced healthcare settings are access to relevant objective tests for children and quality assurance to obtain reliable results.

EXPERT OPINION

We highlight the importance of diagnosing asthma in school-age children using objective tests and outline a practical approach for the use of widely available tests. We also review challenges and barriers to implementation of objective testing in children managed outside specialist settings.

Assessment of prevalence and characteristics of asthma-COPD overlap among patients with chronic airflow obstruction

Given the paucity of research on asthma-chronic obstructive pulmonary disease (COPD) overlap (ACO) and the high prevalence of co-morbidities and healthcare utilization associated with it, the current study looked at the prevalence of ACO and its clinico-radiological phenotype in patients with chronic airflow obstruction. The study was conducted at a tertiary care hospital in North India. Patients over 40 with COPD or asthma were screened for inclusion in the ACO, asthma, and COPD groups. The ACO and COPD groups were further investigated. The clinical characteristics, lung functions, health-related quality of life, and radiological features of both groups were investigated and compared. ACO was discovered in 16.3% of patients with chronic airflow obstruction (asthma and COPD). The most commonly observed symptoms at presentation in the evaluated ACO patients (n=77) were shortness of breath, wheezing, cough, and expectoration (mean age at presentation: 57.9; mean duration of illness: 8.62 years). Exacerbation rates in ACO patients were significantly higher than in COPD patients (p<0.001). The ACO group had a significantly greater mean change in FEV1 post-bronchodilator in millilitres (ml) and percentage (379.61 ml and 37.72%) than the COPD group (p<0.001). The proportion of patients with emphysema was lower in the ACO group than in the COPD group (p<0.001). The ACO and COPD groups did not differ significantly in major airway wall thickness (p=0.3), but the COPD group had a significantly higher proportion of patients with vascular attenuation and distortion (p<0.001). Patients with COPD had a higher degree of hyperinflation, according to high resolution computed tomography (HRCT) indices. This study found that patients with ACO have a distinct phenotype in terms of clinical presentation and HRCT features. More research on the radiological features of ACO is required to identify the anatomical abnormalities involved in the disease's pathogenesis and to validate the radiological features of ACO.

Preventing unscheduled hospitalisations from asthma: a retrospective cohort study using routine primary and secondary care data in the UK (The PUSH-Asthma Study)-protocol paper

INTRODUCTION

Asthma is the most common chronic respiratory disease in children and adults. Asthma results in significant disease-related morbidity, healthcare costs and, in some cases, death. Despite efforts through implementation of national guidelines to improve asthma care, the UK has one of the highest asthma-related morbidity and mortality rates in the western world. New approaches are necessary to prevent asthma attacks in children and adults. The objectives of this study are to assess the association between demographic and clinical factors and asthma-related hospital admissions in children and adults, describe the epidemiology of asthma phenotypes among hospital attenders, and externally validate existing asthma risk prediction models.

METHODS AND ANALYSIS

This is a retrospective cohort study of children and adults with asthma. Data will be extracted from the Clinical Practice Research Datalink (CPRD) Aurum database, which holds anonymised primary care data for over 13 million actively registered patients and covers approximately 19% of the UK population. The primary outcome will be asthma-related hospital admissions. The secondary outcomes will be prescriptions of short courses of oral corticosteroids (as a surrogate measure for asthma exacerbations), a composite outcome measure including hospital admissions and prescriptions of short courses of oral corticosteroids and delivery of asthma care management following hospital discharge. The primary analysis will use a Poisson regression model to assess the association between demographic and clinical risk factors and the primary and secondary outcomes. Latent class analysis will be used to identify distinct subgroups, which will further our knowledge on potential phenotypes of asthma among patients at high risk of asthma-related hospital admissions. A Concordance statistic (C-statistic) and logistic regression model will also be used to externally validate existing risk prediction models for asthma-related hospitalisations to allow for the optimal model to be identified and evaluated provide evidence for potential use of the optimal performing risk prediction model in primary care.

ETHICS AND DISSEMINATION

This study was approved by the CPRD Independent Scientific Advisory Committee (reference number: 21_000512). Findings from this study will be published in a peer-reviewed journal and disseminated at national and international conferences.

Anti-IL-5 therapies for asthma

BACKGROUND

This is the second update of previously published reviews in the Cochrane Library (2015, first update 2017). Interleukin-5 (IL-5) is the main cytokine involved in the proliferation, maturation, activation and survival of eosinophils, which cause airway inflammation and are a classic feature of asthma. Studies of monoclonal antibodies targeting IL-5 or its receptor (IL-5R) suggest they reduce asthma exacerbations, improve health-related quality of life (HRQoL) and lung function in appropriately selected patients, justifying their inclusion in the latest guidelines.

OBJECTIVES

To compare the effects of therapies targeting IL-5 signalling (anti-IL-5 or anti-IL-5Rα) with placebo on exacerbations, health-related quality-of-life (HRQoL) measures and lung function in adults and children with chronic asthma, and specifically in those with eosinophilic asthma refractory to existing treatments.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, and two trials registers, manufacturers' websites, and reference lists of included studies. The most recent search was 7 February 2022.

SELECTION CRITERIA

We included randomised controlled trials comparing mepolizumab, reslizumab and benralizumab versus placebo in adults and children with asthma.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and analysed outcomes using a random-effects model. We used standard methods expected by Cochrane.

MAIN RESULTS

Seventeen studies on about 7600 participants met the inclusion criteria. Six used mepolizumab, five used reslizumab, and six used benralizumab. One study using benralizumab was terminated early due to sponsor decision and contributed no data. The studies were predominantly on people with severe eosinophilic asthma, which was similarly but variably defined. One was in children aged 6 to 17 years; nine others included children over 12 years but did not report results by age group separately. We deemed the overall risk of bias to be low, with all studies contributing data of robust methodology. We considered the certainty of the evidence for all comparisons to be high overall using the GRADE scheme, except for intravenous (IV) mepolizumab and subcutaneous (SC) reslizumab because these are not currently licensed delivery routes. The anti-IL-5 treatments assessed reduced rates of 'clinically significant' asthma exacerbation (defined by treatment with systemic corticosteroids for three days or more) by approximately half in participants with severe eosinophilic asthma on standard care (at least medium-dose inhaled corticosteroids (ICS)) with poorly controlled disease (either two or more exacerbations in the preceding year or Asthma Control Questionnaire (ACQ) score of 1.5 or more), except for reslizumab SC. The rate ratios for these effects were 0.45 (95% confidence interval (CI) 0.36 to 0.55; high-certainty evidence) for mepolizumab SC, 0.53 (95% CI 0.44 to 0.64; moderate-certainty evidence) for mepolizumab IV, 0.43 (95% CI 0.33 to 0.55; high-certainty evidence) for reslizumab IV, and 0.59 (95% CI 0.52 to 0.66; high-certainty evidence) for benralizumab SC. Non-eosinophilic participants treated with benralizumab also showed a significant reduction in exacerbation rates, an effect not seen with reslizumab IV, albeit in only one study. No data were available for non-eosinophilic participants treated with mepolizumab. There were improvements in validated HRQoL scores with all anti-IL-5 agents in severe eosinophilic asthma. This met the minimum clinically important difference (MCID) for the broader St. George's Respiratory Questionnaire (SGRQ; 4-point change) for benralizumab only, but the improvement in the ACQ and Asthma Quality of Life Questionnaire (AQLQ), which focus on asthma symptoms, fell short of the MCID (0.5 point change for both ACQ and AQLQ) for all of the interventions. The evidence for an improvement in HRQoL scores in non-eosinophilic participants treated with benralizumab and reslizumab was weak, but the tests for subgroup difference were negative. All anti-IL-5 treatments produced small improvements in mean pre-bronchodilator forced expiratory flow in one second (FEV1) of between 0.08 L and 0.15 L in eosinophilic participants, which may not be sufficient to be detected by patients. There were no excess serious adverse events with any anti-IL-5 treatment; in fact, there was a reduction in such events with benralizumab, likely arising from fewer asthma-related hospital admissions. There was no difference compared to placebo in adverse events leading to discontinuation with mepolizumab or reslizumab, but significantly more discontinued benralizumab than placebo, although the absolute numbers were small (42/2026 (2.1%) benralizumab versus 11/1227 (0.9%) placebo). The implications for efficacy or adverse events are unclear.

AUTHORS' CONCLUSIONS

Overall this analysis supports the use of anti-IL-5 treatments as an adjunct to standard care in people with severe eosinophilic asthma and poor symptom control. These treatments roughly halve the rate of asthma exacerbations in this population. There is limited evidence for improved HRQoL scores and lung function, which may not meet clinically detectable levels. The studies did not report safety concerns for mepolizumab or reslizumab, or any excess serious adverse events with benralizumab, although there remains a question over adverse events significant enough to prompt discontinuation. Further research is needed on biomarkers for assessing treatment response, optimal duration and long-term effects of treatment, risk of relapse on withdrawal, non-eosinophilic patients, children (particularly under 12 years), comparing anti-IL-5 treatments to each other and, in patients meeting relevant eligibility criteria, to other biological (monoclonal antibody) therapies. For benralizumab, future studies should closely monitor rates of adverse events prompting discontinuation.