Epidemiology of asthma exacerbations

Asthma exacerbations and airway redox imbalance under type 2 inflammatory conditions

Asthma is a chronic inflammatory airway disease characterized by bronchial hyperresponsiveness and reversibility. Despite considerable advances in asthma treatment based on our understanding of its pathophysiology, asthma exacerbations remain challenging. To reduce asthma exacerbations, it is essential to identify triggers, patients' risk factors, and underlying mechanisms. While exposure to viruses and environmental stimuli are known common triggers for asthma exacerbations, the key factors involved in asthma exacerbations have been identified as type 2 inflammation. Type 2 inflammatory biomarkers have been demonstrated to be useful in predicting individuals at risk of exacerbations. Furthermore, recent clinical trials of targeted biological therapy, which blocks the type 2 pathway, have supported the critical role of type 2 inflammation in asthma exacerbations. Although the specific mechanisms linking type 2 inflammation to asthma exacerbations have not yet been fully elucidated, increasing evidence shows that reduction/oxidation (redox) imbalance likely plays an important role in this association. Under type 2 inflammatory conditions, human airway epithelial cells activate 15-lipoxygenase-1 in complex with phosphatidylethanolamine binding protein-1, leading to the generation of electrophilic hydroperoxyl-phospholipids. When the accumulation of reactive lipid peroxidation surpasses a specific glutathione-dependent activity, these electrophilic compounds are not neutralized, leading to programmed cell death, ferroptosis. Reduced glutathione levels, caused by type 2 inflammation, may impair its ability to neutralize reactive lipid peroxidation. The accumulation of lipid peroxidation with intracellular redox imbalance may contribute to asthma exacerbations in individuals with type 2 inflammation. Inhibiting the ferroptotic pathway holds promise as a therapeutic strategy to alleviate asthma exacerbations.

Environmental, healthcare and societal impacts of asthma: a UK model-based assessment

Background

This study aimed to assess the broader environmental, healthcare and societal impacts across the entire asthma pathway from diagnosis to treatment in the UK.

Methods

A comprehensive cost-of-illness framework was developed considering the effects of the full asthma patient pathway, including greenhouse gas emissions generated from inhalers, National Health Service (NHS) costs, health-related quality of life and productivity losses. The model was based on published literature and clinical expert opinion to accurately estimate, in monetary terms, the net present value of the asthma pathway impacts for 2022-2031.

Results

The estimated net present value of the environmental, healthcare and societal impacts of the asthma pathway was £47 billion over the 2022-2031 period in the UK. Loss of disease control was a key contributor to higher greenhouse gas emissions and NHS costs. In 2022, a patient with non-severe uncontrolled asthma was estimated to incur 22% higher NHS costs than a patient with controlled asthma, while generating 0.1 t more of CO2 equivalent emissions. In the same year, the total direct impacts per patient with severe asthma were four times higher than for a patient with non-severe controlled asthma, with 0.54 t CO2 equivalent of greenhouse gas emissions. Moreover, as much as 77% of the total economic impact was driven by worsening health-related quality of life and productivity impacts occurring when patients' symptoms were uncontrolled.

Conclusions

Uncontrolled asthma significantly impacts patients, the economy and the environment in the UK. Our results emphasise the need for a holistic approach in controlling asthma and should be carefully considered when developing policies to mitigate the overall burden of the disease.

Usability and feasibility of the Test of Adherence to Inhalers (TAI) Toolkit in daily clinical practice: The BANANA study

The Test of Adherence to Inhalers (TAI) Toolkit links an adherence measurement instrument (the TAI) to proven effective interventions for different causes of non-adherence to inhaled medication. This study aimed to assess the usability and feasibility of the TAI Toolkit in clinical practice. The TAI Toolkit was piloted in eight primary and secondary care settings. Each study site included 10 patients with asthma and/or COPD and suspected non-adherence. Healthcare professionals (HCPs) recorded clinical data and TAI Toolkit outcomes. Data on usability and feasibility were collected in semi-structured interviews and with the System Usability Score (SUS). Of the included patients, 81% were non-adherent, and sporadic non-adherence was the most common (69%). The TAI Toolkit was valued with a mean SUS-score of 85.9 by the HCPs. They found the toolkit to 'be visually attractive', 'easy-to-use' and 'give insight into patients' adherence', thereby offering good potential for its use in clinical practice.

Evaluation of the implementation of evidence-based pediatric asthma exacerbation treatments in a regional consortium of emergency medical Services Agencies

OBJECTIVE

Asthma exacerbations are a frequent reason for pediatric emergency medical services (EMS) encounters. The objective of this study was to examine the implementation of evidence-based treatments for pediatric asthma in a regional consortium of EMS agencies.

METHODS

This retrospective study applied the Reach, Effectiveness, Adoption, Implementation, and Maintenance (RE-AIM) implementation framework to data from an EMS agency consortium in the Cincinnati, Ohio region. The study analyzed one year before an oral systemic corticosteroid (OCS) option was added to the agencies' protocol, and five years after the protocol change. We constructed logistic regression models for the primary outcome of Reach, defined as the proportion of pediatric asthma patients who received a systemic corticosteroid. We modeled Maintenance (Reach measured monthly over time) using time series models.

RESULTS

A total of 713 patients were included, 133 pre- and 580 post-protocol change. In terms of Reach, 3% (n = 4) of eligible patients received a systemic corticosteroid pre-OCS versus 20% (n = 116) post-OCS. Multivariable modeling of Reach revealed the study period, EMS transport time, months since implementation of OCS, and number of bronchodilators administered by EMS as significant covariates for the administration of a systemic corticosteroid. For Maintenance, it took approximately two years to reach maximal administration of systemic corticosteroids.

CONCLUSIONS

Indicators of asthma severity and time since the protocol change were significantly associated with EMS administration of systemic corticosteroids to pediatric asthma patients. The two-year time for maximal Reach suggests further work is required to understand how to best implement evidence-based pediatric asthma treatments in EMS.

Pediatric asthma exacerbation and COVID-19 pandemic: Impacts, challenges, and future considerations

OBJECTIVE

Asthma, a common disease among children and adolescents, poses a great health risk when ignored; therefore, a thorough follow-up to prevent exacerbations is emphasized. The aim of the present study is to investigate asthma exacerbation in children during the Coronavirus disease 2019 (COVID-19) era.

DATA SOURCES

This narrative review has been done by searching the PubMed and Embase databases using Asthma, COVID-19, Pandemic, and Symptom flare up as keywords.

STUDY SELECTIONS

Studies related to asthma exacerbation in COVID-19 pandemic were included.

RESULTS

Based on studies, controlled or mild to moderate asthma has not been considered a risk factor for COVID-19 severity and has not affected hospitalization, intensive care unit (ICU) admission, and mortality. Surprisingly, emergent and non-emergent visits and asthmatic attacks decreased during the pandemic. The three main reasons for decreased incidence and exacerbation of asthma episodes in the COVID-19 era included reduced exposure to environmental allergens, increasing the acceptance of treatment by pediatrics and caregivers, and decreased risk of other respiratory viral infections. Based on the available studies, COVID-19 vaccination had no serious side effects, except in cases of uncontrolled severe asthma, and can be injected in these children. Also, there was no conclusive evidence of asthma exacerbation after the injection of COVID-19 vaccines.

CONCLUSION

Further studies are recommended to follow the pattern of asthma in the post-pandemic situation and to become prepared for similar future conditions.

Asthma exacerbations in the pediatric emergency area: Evaluation and prospects for improvement of pre-hospital care

INTRODUCTION

The frequency of visits to emergency department for asthma is a significant public health problem in pediatrics. This study aimed to identify the characteristics of children who visited the pediatric emergency department for asthma exacerbation and evaluated their therapeutic management prior to admission.

METHODS

A prospective study was conducted over a 6-month period in the pediatric emergency departments of five hospitals involving children aged 1-16 years admitted to the department with a clinical diagnosis of asthma exacerbation.

RESULTS

In all, 143 patients were enrolled in the study. Asthma episodes were moderate to severe in 69.2% of cases (n = 99). Initial treatment prior to admission to the emergency department was adequate in only 17.5% of cases (n = 25). Hospitalization for more than 24 h occurred in 18.2% (n = 26) patients. In children aged <3 years, viral infection was present in 91.4% cases (n = 64) and exacerbations were more severe in younger patients (P = 0.002) and children belonging to low-income stratum (P = 0.025). Only 17.4% (n = 25) were positive for SARS-CoV-2 (antigen test or polymerase chain reaction test), suggesting that the involvement of traditional respiratory viruses in asthma exacerbation continued even during pandemic. Regarding the pre-hospital care, 70.6% (n = 101) had received prior treatment, but this treatment was inadequate in 53.1% cases (n = 76).

CONCLUSION

This study showed that asthmatic children and their families had little knowledge about the disease and that physicians must be sufficiently aware of current recommendations for managing asthmatic children. Admission to the emergency department for asthma could be avoided partially by better diagnosis and therapeutic education.

Acute Bronchitis and Bronchiolitis Infection in Children with Asthma and Allergic Rhinitis: A Retrospective Cohort Study Based on 5,027,486 Children in Taiwan

This study evaluated the risks of childhood acute bronchitis and bronchiolitis (CABs) for children with asthma or allergic rhinitis (AR). Using insurance claims data of Taiwan, we identified, from children of ≤12 years old in 2000-2016, cohorts with and without asthma (N = 192,126, each) and cohorts with and without AR (N = 1,062,903, each) matched by sex and age. By the end of 2016, the asthma cohort had the highest bronchitis incidence, AR and non-asthma cohorts followed, and the lowest in the non-AR cohort (525.1, 322.4, 236.0 and 169.9 per 1000 person-years, respectively). The Cox method estimated adjusted hazard ratios (aHRs) of bronchitis were 1.82 (95% confidence interval (CI), 1.80-1.83) for the asthma cohort and 1.68 (95% CI, 1.68-1.69) for the AR cohort, relative to the respective comparisons. The bronchiolitis incidence rates for these cohorts were 42.7, 29.5, 28.5 and 20.1 per 1000 person-years, respectively. The aHRs of bronchiolitis were 1.50 (95% CI, 1.48-1.52) for the asthma cohort and 1.46 (95% CI, 1.45-1.47) for the AR cohort relative to their comparisons. The CABs incidence rates decreased substantially with increasing age, but were relatively similar for boys and girls. In conclusion, children with asthma are more likely to develop CABs than are children with AR.

Dexmedetomidine Protects against Airway Inflammation and Airway Remodeling in a Murine Model of Chronic Asthma through TLR4/NF-κB Signaling Pathway

Asthma is a common respiratory disease characterized by chronic airway inflammation. Dexmedetomidine (DEX), a highly selective α2 adrenergic receptor agonist, has been shown to participate in regulating inflammatory states and thus exert organ protective actions. However, the potential of DEX in asthma is still unknown. This study is aimed at investigating the role of DEX in a mouse model of house dust mite- (HDM-) induced asthma and exploring its underlying mechanism. Here, we found that DEX treatment significantly ameliorated airway hyperresponsiveness, airway inflammation, and airway remodeling in the asthmatic mice, which were similar to the efficacy of the reference anti-inflammatory drug dexamethasone. In addition, DEX reversed the increased expression of toll-like receptor 4 (TLR4) and its downstream signaling adaptor molecule nuclear factor-κB (NF-κB) in the lung tissue of asthmatic mice. Furthermore, these protective effects of DEX were abolished by yohimbine, an α2 adrenergic receptor antagonist. These results indicate that DEX is capable of ameliorating airway inflammation and remodeling in asthmatic mice, and this protective effect is associated with the inhibition of the TLR4/NF-κB signaling pathway.

Characteristics and outcomes of COVID-19 patients with and without asthma from the United States, South Korea, and Europe

Objective: Large international comparisons describing the clinical characteristics of patients with COVID-19 are limited. The aim of the study was to perform a large-scale descriptive characterization of COVID-19 patients with asthma.Methods: We included nine databases contributing data from January to June 2020 from the US, South Korea (KR), Spain, UK and the Netherlands. We defined two cohorts of COVID-19 patients ('diagnosed' and 'hospitalized') based on COVID-19 disease codes. We followed patients from COVID-19 index date to 30 days or death. We performed descriptive analysis and reported the frequency of characteristics and outcomes in people with asthma defined by codes and prescriptions.Results: The diagnosed and hospitalized cohorts contained 666,933 and 159,552 COVID-19 patients respectively. Exacerbation in people with asthma was recorded in 1.6-8.6% of patients at presentation. Asthma prevalence ranged from 6.2% (95% CI 5.7-6.8) to 18.5% (95% CI 18.2-18.8) in the diagnosed cohort and 5.2% (95% CI 4.0-6.8) to 20.5% (95% CI 18.6-22.6) in the hospitalized cohort. Asthma patients with COVID-19 had high prevalence of comorbidity including hypertension, heart disease, diabetes and obesity. Mortality ranged from 2.1% (95% CI 1.8-2.4) to 16.9% (95% CI 13.8-20.5) and similar or lower compared to COVID-19 patients without asthma. Acute respiratory distress syndrome occurred in 15-30% of hospitalized COVID-19 asthma patients.Conclusion: The prevalence of asthma among COVID-19 patients varies internationally. Asthma patients with COVID-19 have high comorbidity. The prevalence of asthma exacerbation at presentation was low. Whilst mortality was similar among COVID-19 patients with and without asthma, this could be confounded by differences in clinical characteristics. Further research could help identify high-risk asthma patients.[Box: see text]Supplemental data for this article is available online at https://doi.org/10.1080/02770903.2021.2025392 .

Spring is associated with increased total and allergenic fungal concentrations in house dust from a pediatric asthma cohort in New York City

Introduction

Asthma and allergy symptoms vary seasonally due to exposure to environmental sources of allergen, including fungi. However, we need an improved understanding of seasonal influence on fungal exposures in the indoor environment. We hypothesized that concentrations of total fungi and allergenic species in vacuumed dust vary significantly by season.

Objective

Assess seasonal variation of indoor fungi with greater implications related to seasonal asthma control.

Methods

We combined next-generation sequencing with quantitative polymerase chain reaction (qPCR) to measure concentrations of fungal DNA in indoor floor dust samples (n = 298) collected from homes participating in the New York City Neighborhood Asthma and Allergy Study (NAAS).

Results

Total fungal concentration in spring was significantly higher than the other three seasons (p ≤ 0.005). Mean concentrations for 78% of fungal species were elevated in the spring (26% were significantly highest in spring, p < 0.05). Concentrations of 8 allergenic fungal species were significantly (p < 0.5) higher in spring compared to at least two other seasons. Indoor relative humidity and temperature were significantly highest in spring (p < 0.05) and were associated with total fungal concentration (R2 = 0.049, R2 = 0.11, respectively).

Conclusion

There is significant seasonal variation in total fungal concentration and concentration of select allergenic species. Indoor relative humidity and temperature may underlie these associations.

Increased versus stable doses of inhaled corticosteroids for exacerbations of chronic asthma in adults and children

BACKGROUND

People with asthma may experience exacerbations, or 'attacks', during which their symptoms worsen and additional treatment is required. Written action plans sometimes advocate a short-term increase in the dose of inhaled corticosteroids (ICS) at the first sign of an exacerbation to reduce the severity of the attack and to prevent the need for oral steroids or hospital admission.

OBJECTIVES

To compare the clinical effectiveness and safety of increased versus stable doses of ICS as part of a patient-initiated action plan for the home management of exacerbations in children and adults with persistent asthma.

SEARCH METHODS

We searched the Cochrane Airways Group Specialised Register, which is derived from searches of the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, and CINAHL (Cumulative Index to Nursing and Allied Health Literature), and handsearched abstracts to 20 December 2021. We also searched major trial registries for ongoing trials.

SELECTION CRITERIA

We included parallel and cross-over randomised controlled trials (RCTs) that allocated people with persistent asthma to take a blinded inhaler in the event of an exacerbation which either increased their daily dose of ICS or kept it stable (placebo).

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials, assessed quality, and extracted data. We reassessed risk of bias for all studies at the result level using the revised risk of bias tool for RCTs (Risk of Bias 2), and employed the GRADE approach to assess our confidence in the synthesised effect estimates. The primary outcome was treatment failure, defined as the need for rescue oral steroids in the randomised population. Secondary outcomes were treatment failure in the subset who initiated the study inhaler (treated population), unscheduled physician visits, unscheduled acute care, emergency department or hospital visits, serious and non-serious adverse events, and duration of exacerbation.

MAIN RESULTS

This review update added a new study that increased the number of people in the primary analysis from 1520 to 1774, and incorporates the most up-to-date methods to assess the likely impact of bias within the meta-analyses. The updated review now includes nine RCTs (1923 participants; seven parallel and two cross-over) conducted in Europe, North America, and Australasia and published between 1998 and 2018. Five studies evaluated adult populations (n = 1247; ≥ 15 years), and four studies evaluated child or adolescent populations (n = 676; < 15 years). All study participants had mild to moderate asthma. Studies varied in the dose of maintenance ICS, age, fold increase of ICS in the event of an exacerbation, criteria for initiating the study inhaler, and allowed medications. Approximately 50% of randomised participants initiated the study inhaler (range 23% to 100%), and the included studies reported treatment failure in a variety of ways, meaning assumptions were required to permit the combining of data. Participants randomised to increase their ICS dose at the first signs of an exacerbation had similar odds of needing rescue oral corticosteroids to those randomised to a placebo inhaler (odds ratio (OR) 0.97, 95% confidence interval (CI) 0.76 to 1.25; 8 studies; 1774 participants; I2 = 0%; moderate quality evidence). We could draw no firm conclusions from subgroup analyses conducted to investigate the impact of age, time to treatment initiation, baseline dose, smoking history, and fold increase of ICS on the primary outcome. Results for the same outcome in the subset of participants who initiated the study inhaler were unchanged from the previous version, which provides a different point estimate with very low confidence due to heterogeneity, imprecision, and risk of bias (OR 0.84, 95% CI 0.54 to 1.30; 7 studies; 766 participants; I2 = 42%; random-effects model). Confidence was reduced due to risk of bias and assumptions that had to be made to include study data in the intention-to-treat and treated-population analyses. Sensitivity analyses that tested the impact of assumptions made for synthesis and to exclude cross-over studies, studies at overall high risk of bias, and those with commercial funding did not change our conclusions. Pooled effects for unscheduled physician visits, unscheduled acute care, emergency department or hospital visits, and duration of exacerbation made it very difficult to determine where the true effect may lie, and confidence was reduced by risk of bias. Point estimates for both serious and non-serious adverse events favoured keeping ICS stable, but imprecision and risk of bias due to missing data and outcome measurement and reporting reduced our confidence in the effects (serious adverse events: OR 1.69, 95% CI 0.77 to 3.71; 2 studies; 394 participants; I² = 0%; non-serious adverse events: OR 2.15, 95% CI 0.68 to 6.73; 2 studies; 142 participants; I² = 0%).

AUTHORS' CONCLUSIONS

Evidence from double-blind trials of adults and children with mild to moderate asthma suggests there is unlikely to be an important reduction in the need for oral steroids from increasing a patient's ICS dose at the first sign of an exacerbation. Other clinically important benefits and potential harms of increased doses of ICS compared with keeping the dose stable cannot be ruled out due to wide confidence intervals, risk of bias in the trials, and assumptions that had to be made for synthesis. Included studies conducted between 1998 and 2018 reflect evolving clinical practice and study methods, and the data do not support thorough investigation of effect modifiers such as baseline dose, fold increase, asthma severity and timing. The review does not include recent evidence from pragmatic, unblinded studies showing benefits of larger dose increases in those with poorly controlled asthma. A systematic review is warranted to examine the differences between the blinded and unblinded trials using robust methods for assessing risk of bias to present the most complete view of the evidence for decision makers.

Epithelial cell responses to rhinovirus identify an early-life-onset asthma phenotype in adults

BACKGROUND

The study of pathogenic mechanisms in adult asthma is often marred by a lack of precise information about the natural history of the disease. Children who have persistent wheezing (PW) during the first 6 years of life and whose symptoms start before age 3 years (PW+) are much more likely to have wheezing illnesses due to rhinovirus (RV) in infancy and to have asthma into adult life than are those who do not have PW (PW-).

OBJECTIVE

Our aim was to determine whether nasal epithelial cells from PW+ asthmatic adults as compared with cells from PW- asthmatic adults show distinct biomechanistic processes activated by RV exposure.

METHODS

Air-liquid interface cultures derived from nasal epithelial cells of 36-year old participants with active asthma with and without a history of PW in childhood (10 PW+ participants and 20 PW- participants) from the Tucson Children's Respiratory Study were challenged with a human RV-A strain (RV-A16) or control, and their RNA was sequenced.

RESULTS

A total of 35 differentially expressed genes involved in extracellular remodeling and angiogenesis distinguished the PW+ group from the PW- group at baseline and after RV-A stimulation. Notably, 22 transcriptomic pathways showed PW-by-RV interactions; the pathways were invariably overactivated in PW+ patients, and were involved in Toll-like receptor- and cytokine-mediated responses, remodeling, and angiogenic processes.

CONCLUSIONS

Asthmatic adults with a history of persistent wheeze in the first 6 years of life have specific biomolecular alterations in response to RV-A that are not present in patients without such a history. Targeting these mechanisms may slow the progression of asthma in these patients.

Sex differences in febrile children with respiratory symptoms attending European emergency departments: An observational multicenter study

Objective

To assess sex differences in presentation and management of febrile children with respiratory symptoms attending European Emergency Departments.

Design and setting

An observational study in twelve Emergency Departments in eight European countries.

Patients

Previously healthy children aged 0–<18 years with fever (≥ 38°C) at the Emergency Department or in the consecutive three days before Emergency Department visit and respiratory symptoms were included.

Main outcome measures

The main outcomes were patient characteristics and management defined as diagnostic tests, treatment and admission. Descriptive statistics were used for patient characteristics and management stratified by sex. Multivariable logistic regression analyses were performed for the association between sex and management with adjustment for age, disease severity and Emergency Department. Additionally, subgroup analyses were performed in children with upper and lower respiratory tract infections and in children below five years.

Results

We included 19,781 febrile children with respiratory symptoms. The majority were boys (54%), aged 1–5 years (58%) and triaged as low urgent (67%). Girls presented less frequently with tachypnea (15% vs 16%, p = 0.002) and increased work of breathing (8% vs 12%, p<0.001) compared with boys. Girls received less inhalation medication than boys (aOR 0.82, 95% CI 0.74–0.90), but received antibiotic treatment more frequently than boys (aOR 1.09, 95% CI 1.02–1.15), which is associated with a higher prevalence of urinary tract infections. Amongst children with a lower respiratory tract infection and children below five years girls received less inhalation medication than boys (aOR 0.77, 95% CI 0.66–0.89; aOR 0.80, 95% CI 0.72–0.90).

Conclusions

Sex differences concerning presentation and management are present in previously healthy febrile children with respiratory symptoms presenting to the Emergency Department. Future research should focus on whether these differences are related to clinicians’ attitudes, differences in clinical symptoms at the time of presentation and disease severity.

Pediatric Prescriptions of Proton Pump Inhibitors in France (2009-2019): A Time-Series Analysis of Trends and Practice Guidelines Impact

OBJECTIVE

To describe the ambulatory proton pump inhibitor (PPI) prescription in French children, its trends, and the impact of French (2014) and international (2018) clinical guidelines.

STUDY DESIGN

We described PPI prescription rates based on national dispensation data in French children (IQVIA's Xponent database, 2009-2019). Using a segmented linear regression, we assessed the impact of clinical guidelines on PPI prescription rates. Analyses were performed for the overall pediatric population and by age subgroups (infants <2 years old, children 2-11 years old, adolescents 12-17 years old).

RESULTS

During the study period, 8 060 288 pediatric PPI prescriptions were filled, with a mean PPI prescription rate of 52.5 per 1000 inhabitants per year. Between 2009 and 2019, the PPI prescription rate increased by 41% in the overall pediatric population (+110% in infants). The PPI prescription rate showed seasonal patterns with peaks in winter. After the release of French guidelines, significant decreases in trends of prescription rates occurred overall (change in trend -0.28, 95% CI -0.34;-0.23) and across all age groups. In infants, this change in trend was not sufficient to reverse the PPI prescription rate that was still increasing over time. In children, the PPI prescription rate slightly decreased and in adolescents, it was stable. After the release of international guidelines, a significant decrease in trend occurred in adolescents only (change in trend -0.26, 95% CI -0.47; -0.04).

CONCLUSIONS

The pediatric PPI prescription rate in France was high, displayed a major increase over the last decade, mainly among infants, and was modestly affected by clinical guidelines.

Development and Application of an Open Tool for Sharing and Analyzing Integrated Clinical and Environmental Exposures Data: Asthma Use Case

BACKGROUND

The Integrated Clinical and Environmental Exposures Service (ICEES) serves as an open-source, disease-agnostic, regulatory-compliant framework and approach for openly exposing and exploring clinical data that have been integrated at the patient level with a variety of environmental exposures data. ICEES is equipped with tools to support basic statistical exploration of the integrated data in a completely open manner.

OBJECTIVE

This study aims to further develop and apply ICEES as a novel tool for openly exposing and exploring integrated clinical and environmental data. We focus on an asthma use case.

METHODS

We queried the ICEES open application programming interface (OpenAPI) using a functionality that supports chi-square tests between feature variables and a primary outcome measure, with a Bonferroni correction for multiple comparisons (α=.001). We focused on 2 primary outcomes that are indicative of asthma exacerbations: annual emergency department (ED) or inpatient visits for respiratory issues; and annual prescriptions for prednisone.

RESULTS

Of the 157,410 patients within the asthma cohort, 26,332 (16.73%) had 1 or more annual ED or inpatient visits for respiratory issues, and 17,056 (10.84%) had 1 or more annual prescriptions for prednisone. We found that close proximity to a major roadway or highway, exposure to high levels of particulate matter ≤2.5 μm (PM2.5) or ozone, female sex, Caucasian race, low residential density, lack of health insurance, and low household income were significantly associated with asthma exacerbations (P<.001). Asthma exacerbations did not vary by rural versus urban residence. Moreover, the results were largely consistent across outcome measures.

CONCLUSIONS

Our results demonstrate that the open-source ICEES can be used to replicate and extend published findings on factors that influence asthma exacerbations. As a disease-agnostic, open-source approach for integrating, exposing, and exploring patient-level clinical and environmental exposures data, we believe that ICEES will have broad adoption by other institutions and application in environmental health and other biomedical fields.

Effect of the COVID-19 Lockdown on Asthma Biological Rhythms

Asthma has a striking temporal character, in which time-of-day, patient age, and season each influence disease activity. The extent to which rhythms in asthma activity reflect exposure to specific disease triggers remains unclear. In this study, we examined how virus mitigation strategies enacted during the COVID-19 pandemic ("lockdown measures") affected rhythms in asthma clinical activity in children. To this end, we retrospectively analyzed asthma clinical presentations in children aged <18 years to our regional academic medical center, comparing 4 years of medical records prior to COVID-19 lockdown measures with the 12 months immediately after the institution of such measures. We correlated these data to positive viral test results, febrile seizures, and allergic clinical surrogates (allergic reaction visits and Emergency Department [ED] antihistamine prescriptions, respectively) over the same time frame. In the 12 months following the institution of the COVID-19 lockdown, positivity rates for common respiratory viruses dropped by 70.2% and ED visits for asthma among children dropped by 62% compared to pre-COVID years. Lockdown suppressed seasonal variation in positive viral tests and asthma ED visits, while diurnal rhythms in asthma visits were unchanged. Asthma seasonality correlated most strongly with rhinovirus positivity both before and after the institution of COVID lockdown measures. Altogether, our data support a causal role for viruses in driving seasonal variability in asthma exacerbations in children.

Age-Dependent Reduction in Asthmatic Pathology through Reprogramming of Postviral Inflammatory Responses

Asthma is a chronic disease of childhood, but for unknown reasons, disease activity sometimes subsides as children mature. In this study, we present clinical and animal model evidence suggesting that the age dependency of childhood asthma stems from an evolving host response to respiratory viral infection. Using clinical data, we show that societal suppression of respiratory virus transmission during coronavirus disease 2019 lockdown disrupted the traditional age gradient in pediatric asthma exacerbations, connecting the phenomenon of asthma remission to virus exposure. In mice, we show that asthmatic lung pathology triggered by Sendai virus (SeV) or influenza A virus is highly age-sensitive: robust in juvenile mice (4-6 wk old) but attenuated in mature mice (>3 mo old). Interestingly, allergen induction of the same asthmatic traits was less dependent on chronological age than viruses. Age-specific responses to SeV included a juvenile bias toward type 2 airway inflammation that emerged early in infection, whereas mature mice exhibited a more restricted bronchiolar distribution of infection that produced a distinct type 2 low inflammatory cytokine profile. In the basal state, aging produced changes to lung leukocyte burden, including the number and transcriptional landscape of alveolar macrophages (AMs). Importantly, depleting AMs in mature mice restored post-SeV pathology to juvenile levels. Thus, aging influences chronic outcomes of respiratory viral infection through regulation of the AM compartment and type 2 inflammatory responses to viruses. Our data provide insight into how asthma remission might develop in children.

Persistent cough and asthma-like symptoms post COVID-19 hospitalization in children

Backgrounds

Respiratory viruses are the main triggers of asthma. Coronavirus is shown to contribute to respiratory tract infections that can lead to prolonged cough and asthma.

Objectives

Present study aimed to determine the risk of developing Persistent cough and asthma-like symptoms in hospitalized children due to COVID-19.

Methods

This prospective study was carried out in a tertiary referral center. During the COVID-19 pandemic, 69 hospitalized pediatric patients admitted with COVID-19 were observed from February 2020 to January 2021. Clinical and laboratory data were recorded, and after discharge, patients were followed and visited for cough and asthma evaluation one, 2 and 6 months later. Patients with asthma-like diagnoses in follow up defined as asthma-like groups, and patients without any sign of asthma were categorized as the non-asthma group. Asthma-like co-morbids and risk factors were evaluated and compared between the two groups.

Results

In follow-up, most of the COVID-19 hospitalized patients (N = 42) (58.5%) were not affected by asthma-like symptoms. 60.9% of the COVID-19 patients were male. The asthma-like group cases had a significantly familial history of asthma (63.0%), past medical history of asthma (33.3%), and Allergic rhinitis (85.2%). Rates of signs and symptoms during hospitalization were significantly higher in patients with COVID-19 and past medical history of asthma.

Conclusions

We found an asthma-like prevalence of 41.5% in the cohort of COVID-19 hospitalized children. Family history of asthma and previous history of asthma and allergic rhinitis are risk factors for asthma-like after COVID-19 hospitalization. COVID-19 presentations are more severe in the asthma-like group.

Interfering with alternatively activated macrophages by CSF-1R inhibition exerts therapeutic capacity on allergic airway inflammation

PURPOSE

Allergic asthma is a chronic inflammatory disorder with airway hyperresponsiveness and tissue remodeling as the main pathological characteristics. The etiology of asthma is relatively complicated, involving genetic susceptibility, epigenetic regulation, environmental factors, and immune imbalance. Colony stimulating factor 1 receptor (CSF-1R), highly expressed in myeloid monocytes, plays an important role in regulating inflammation. However, the pathological role of CSF-1R and the therapeutic effects of CSF-1R inhibitor in allergic airway inflammation remain indistinct.

METHODS

The house dust mite (HDM)-triggered allergic airway inflammation model was conducted to fully uncover the efficacies of CSF-1R inhibition, as illustrated by histopathological examinations, biochemical analysis, ELISA, RT-PCR, Western blotting assay, immunofluorescence, and flow cytometry. Furthermore, bone marrow-derived macrophages (BMDMs) were differentiated and polarized upon IL-4/IL-13 induction to clarify the underlying mechanisms of CSF-1R inhibition.

RESULTS

Herein, we presented that the expression of CSF-1R was increased in HDM-induced experimental asthma and inhibition of CSF-1R displayed dramatic effects on the disease severity of asthma, referring to suppressing the secretion of allergic mediators, dysfunction of airway epithelium, and infiltration of inflammatory cells. Furthermore, CSF-1R inhibitor could markedly restrain the polarization and expression of transcriptional factors of alternatively activated macrophages (AAMs) in the presence of IL-4/IL-13 and reduce the recruitment of CSF-1R-dominant macrophages, both in acute and chronic allergic airway inflammation model.

CONCLUSION

Collectively, our findings demonstrated the molecular pathological mechanism of CSF-1R in allergic airway diseases and suggested that targeting CSF-1R might be an alternative intervention strategy on the homeostasis of airway immune microenvironment in asthma.

Gekko gecko extract attenuates airway inflammation and mucus hypersecretion in a murine model of ovalbumin-induced asthma

ETHNOPHARMACOLOGICAL RELEVANCE

Gekko gecko is used as a traditional medicine for various diseases including respiratory disorders in northeast Asian countries, mainly Korea, Japan, and China.

AIM OF THE STUDY

Allergic asthma is a chronic respiratory disease caused by an inappropriate immune response. Due to the recent spread of coronavirus disease 2019, interest in the treatment of pulmonary disorders has rapidly increased. In this study, we investigated the anti-asthmatic effects of G. gecko extract (GGE) using an established mouse model of ovalbumin-induced asthma.

MATERIALS AND METHODS

To evaluate the anti-asthmatic effects of GGE, we evaluated histological changes and the responses of inflammatory mediators related to allergic airway inflammation. Furthermore, we investigated the regulatory effects of GGE on type 2 helper T (Th2) cell activation.

RESULTS

Administration of GGE attenuated asthmatic phenotypes, including inflammatory cell infiltration, mucus production, and expression of Th2 cytokines. Furthermore, GGE treatment reduced Th2 cell activation and differentiation.

CONCLUSIONS

These results indicate that GGE alleviates allergic airway inflammation by regulating Th2 cell activation and differentiation.

Use of Fractional Exhaled Nitric Oxide to Guide the Treatment of Asthma: An Official American Thoracic Society Clinical Practice Guideline

Background: The fractional exhaled nitric oxide (FE_NO) test is a point-of-care test that is used in the assessment of asthma.

Objective: To provide evidence-based clinical guidance on whether FE_NO testing is indicated to optimize asthma treatment in patients with asthma in whom treatment is being considered.

Methods: An international, multidisciplinary panel of experts was convened to form a consensus document regarding a single question relevant to the use of FE_NO. The question was selected from three potential questions based on the greatest perceived impact on clinical practice and the unmet need for evidence-based answers related to this question. The panel performed systematic reviews of published randomized controlled trials between 2004 and 2019 and followed the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) evidence-to-decision framework to develop recommendations. All panel members evaluated and approved the recommendations.

Main Results: After considering the overall low quality of the evidence, the panel made a conditional recommendation for FE_NO-based care. In patients with asthma in whom treatment is being considered, we suggest that FE_NO is beneficial and should be used in addition to usual care. This judgment is based on a balance of effects that probably favors the intervention; the moderate costs and availability of resources, which probably favors the intervention; and the perceived acceptability and feasibility of the intervention in daily practice.

Conclusions: Clinicians should consider this recommendation to measure FE_NO in patients with asthma in whom treatment is being considered based on current best available evidence.

Interrupting the Conversation: Implications for Crosstalk Between Viral and Bacterial Infections in the Asthmatic Airway

Asthma is a heterogeneous, chronic respiratory disease affecting 300 million people and is thought to be driven by different inflammatory endotypes influenced by a myriad of genetic and environmental factors. The complexity of asthma has rendered it challenging to develop preventative and disease modifying therapies and it remains an unmet clinical need. Whilst many factors have been implicated in asthma pathogenesis and exacerbations, evidence indicates a prominent role for respiratory viruses. However, advances in culture-independent detection methods and extensive microbial profiling of the lung, have also demonstrated a role for respiratory bacteria in asthma. In particular, airway colonization by the Proteobacteria species Nontypeable Haemophilus influenzae (NTHi) and Moraxella catarrhalis (Mcat) is associated with increased risk of developing recurrent wheeze and asthma in early life, poor clinical outcomes in established adult asthma and the development of more severe inflammatory phenotypes. Furthermore, emerging evidence indicates that bacterial-viral interactions may influence exacerbation risk and disease severity, highlighting the need to consider the impact chronic airway colonization by respiratory bacteria has on influencing host responses to viral infection. In this review, we first outline the currently understood role of viral and bacterial infections in precipitating asthma exacerbations and discuss the underappreciated potential impact of bacteria-virus crosstalk in modulating host responses. We discuss the mechanisms by which early life infection may predispose to asthma development. Finally, we consider how infection and persistent airway colonization may drive different asthma phenotypes, with a view to identifying pathophysiological mechanisms that may prove tractable to new treatment modalities.

Association of obstructive sleep apnea with all-cause readmissions after hospitalization for asthma exacerbation in adults aged 18-54 years: a population-based study, 2010-2013

OBJECTIVE

To investigate associations between obstructive sleep apnea (OSA) and readmission risk after hospitalization for asthma exacerbation.

METHODS

We conducted a retrospective, population-based cohort study using State Inpatient Databases from seven U.S. states (Arkansas, California, Florida, Iowa, Nebraska, New York, and Utah) from 2010 to 2013. We identified all adults (aged 18-54 years) hospitalized for asthma exacerbation. The outcome measure was all-cause readmissions within one year after hospitalization for asthma exacerbation. To determine associations between OSA and readmission risk, we constructed negative binomial regression models estimating the incidence rate ratio (IRR) for readmissions and Cox proportional hazards models estimating hazard rate (HR) for the time-to-first readmission.

RESULTS

Among 65,731 patients hospitalized for asthma exacerbation, 6,549 (10.0%) had OSA. Overall, OSA was associated with significantly higher incident rate of all cause readmission (1.36 vs. 0.85 readmissions per person-year; unadjusted IRR 1.60; 95%CI 1.54-1.66). Additionally, OSA was associated with higher incident rates of readmissions for five major diseases-asthma (IRR 1.21; 95%CI 1.15-1.27), COPD (IRR 2.03; 95%CI 1.88-2.19), respiratory failure (IRR 3.04; 95%CI 2.76-3.34), pneumonia (IRR 1.67; 95%CI 1.49-1.88), and congestive heart failure (IRR 3.78; 95%CI 3.36-4.24), compared to non-OSA. The Cox model demonstrated that patients with OSA had significantly higher rates for all-cause readmission compared to those without OSA (HR 1.56; 95% CI 1.50-1.62). These associations remained significant after adjustment for confounders.

CONCLUSIONS

The observed association of OSA with a higher risk of readmissions after hospitalization for asthma exacerbation underscores the importance of identifying coexistent OSA in this population and optimizing both OSA and asthma management.

Asthma and COVID-19: Emphasis on Adequate Asthma Control

Asthmatics are at an increased risk of developing exacerbations after being infected by respiratory viruses such as influenza virus, parainfluenza virus, and human and severe acute respiratory syndrome coronaviruses (SARS-CoV). Asthma, especially when poorly controlled, is an independent risk factor for developing pneumonia. A subset of asthmatics can have significant defects in their innate, humoral, and cell-mediated immunity arms, which may explain the increased susceptibility to infections. Adequate asthma control is associated with a significant decrease in episodes of exacerbation. Because of their wide availability and potency to promote adequate asthma control, glucocorticoids, especially inhaled ones, are the cornerstone of asthma management. The current COVID-19 pandemic affects millions of people worldwide and possesses mortality several times that of seasonal influenza; therefore, it is necessary to revisit this subject. The pathogenesis of SARS-CoV-2, the virus that causes COVID-19, can potentiate the development of acute asthmatic exacerbation with the potential to worsen the state of chronic airway inflammation. The relationship is evident from several studies that show asthmatics experiencing a more adverse clinical course of SARS-CoV-2 infection than nonasthmatics. Recent studies show that dexamethasone, a potent glucocorticoid, and other inhaled corticosteroids significantly reduce morbidity and mortality among hospitalized COVID-19 patients. Hence, while we are waiting for more studies with higher level of evidence that further narrate the association between COVID-19 and asthma, we advise clinicians to try to achieve adequate disease control in asthmatics as it may reduce incidences and severity of exacerbations especially from SARS-CoV-2 infection.

Precision cut lung slices: an ex vivo model for assessing the impact of immunomodulatory therapeutics on lung immune responses

Chronic inflammatory diseases of the respiratory tract, such as chronic obstructive pulmonary disease (COPD) and asthma, are severe lung diseases that require effective treatments. In search for new medicines for these diseases, there is an unmet need for predictive and translatable disease-relevant in vitro/ex vivo models to determine the safety and efficacy of novel drug candidates. Here, we report the use of precision cut lung slices (PCLS) as a potential ex vivo platform to study compound effects in a physiologically relevant environment. PCLS derived from an elastase-challenged mouse model display key characteristics of increased inflammation ex vivo, which is exacerbated further upon challenge with LPS, mimicking the immune insult of a pathogen triggering disease exacerbation. Such LPS-induced inflammatory conditions are significantly abrogated by immunomodulatory agents targeting specific inflammatory signaling pathways in the absence of cytotoxic effects in lung slices. Thus, an ex vivo model of PCLS with a simulated pathogenic insult can replicate proposed in vivo pharmacological effects and thus could potentially act as a valuable tool to investigate the underlying mechanisms associated with lung safety, therapeutic efficacy and exacerbations with infection.

Current long-acting muscarinic antagonists for the treatment of asthma

INTRODUCTION

The role of long-acting muscarinic antagonists (LAMAs) is well established in uncontrolled asthma, but not in milder stages.

AREAS COVERED

This review examines the main randomized controlled trials (RCTs) that have investigated LAMAs administered as monotherapy or in combination to asthmatic patients, according to the different phenotypes. It offers an overview of the role of LAMAs or their fixed dose combinations (FDCs) in the treatment across all the different stages of asthma.

EXPERT OPINION

Tiotropium is now widely recognized as treatment for moderate to severe uncontrolled asthma (step 4-5) in adults and children. The most recent new evidence is: a) in adults, three different LAMA/long-acting β₂-agonist (LABA)/inhaled corticosteroid (ICS) FDCs have been recently approved, extending the treatment options for these patients; b) therapy with LAMAs does not depend on patient's Th2 status and justifies the indication regardless of patient's phenotyping; c) in the milder stages, the high variability of response to LAMAs and the lack of a good phenotyping of patients represents the main obstacle in prescribing LAMAs. A better characterization of parasympathetic tone activity could improve LAMAs prescription.

Association of Preexisting Asthma and Other Allergic Diseases With Mortality in COVID-19 Patients: A Systematic Review and Meta-Analysis

Background: Respiratory viruses are known to contribute to asthma exacerbations. A meta-analysis of three studies reported no association between coronavirus disease 2019 (COVID-19) mortality and preexisting asthma. This study aimed to investigate the mortality of patients with COVID-19 in relation to preexisting asthma and other allergic diseases associated with changes in respiratory function. Methods: PubMed, Embase, and the Cochrane Library were queried for papers published up to April 9, 2021: (1) population: patients who tested positive for SARS-CoV-2 according to the WHO guidelines; (2) exposure: preexisting asthma or allergic rhinitis; (3) outcomes: mortality, ICU admission, and/or hospitalization; and (4) language: English. For studies that reported adjusted models, the most adjusted model was used for this meta-analysis; otherwise, unadjusted results were used. Results: Twenty-four studies (1,169,441 patients) were included in this meta-analysis. Patients who died of COVID-19 were not more likely to have preexisting asthma (OR = 0.95, 95%CI: 0.78-1.15, P = 0.602; I2 = 63.5%, Pheterogeneity < 0.001). Patients with COVID-19 and admitted to the ICU (OR = 1.17, 95%CI: 0.81-1.68, P = 0.407; I2 = 91.1%, Pheterogeneity = 0.407), or hospitalized (OR = 0.91, 95%CI: 0.76-1.10, P = 0.338; I2 = 79.1%, Pheterogeneity < 0.001) were not more likely to have preexisting asthma. The results for mortality and hospitalization remained non-significant when considering the adjusted and unadjusted models separately. The results from the sensitivity analyses were consistent with the primary analyses, suggesting the robustness of our results. Conclusion: This meta-analysis suggests that the patients who died from COVID-19, were admitted to the ICU, or hospitalized were not more likely to have asthma.

Overweight improves long-term survival in Japanese patients with asthma

BACKGROUND

Obesity is a risk factor for severe and difficult-to-treat asthma. However, the impact of different physiques on long-term outcomes is poorly understood. We aimed to investigate the correlation between obesity and asthma-associated long-term mortality in Japanese adults.

METHODS

From the data on 3146 individuals with air pollution-related respiratory diseases in the Omuta City Air Pollution-Related Health Damage Cohort Program, 697 adult patients with asthma were analyzed. Hazard ratios for long-term all-cause and respiratory disease -related mortality were compared in patients with different physiques using the Cox proportional hazard models. The classification of physiques was based on the WHO obesity criteria.

RESULTS

Of the 697 patients, 439 died during the median observation period of 26.3 years. The number (% of total) of underweight, normal-weight, pre-obese, and obese class I-III individuals were 75 (10.8%), 459 (65.9%), 140 (20.1%), and 23 (3.3%), respectively. The Cox proportional hazard model (adjusted hazard ratio [95% confidence interval], P value) showed that pre-obese group had a significantly reduced risk for all-cause (0.65 [0.51 to 0.83], P < 0.05) and respiratory disease (0.55 [0.37 to 0.81], P < 0.05)-related mortality related to normal-weight group.

CONCLUSIONS

Our cohort program demonstrated that being slightly overweight may reduce the risk of long-term mortality in patients with asthma. However, the influence of obesity on long-term outcomes remains unclear in asthma, because of the small number of obese patients included in our study. Our findings suggest that interventions, including nutrition and exercises, should be provided to Japanese patients with asthma.

Maternal asthma and early fetal growth, the MAESTRO study

BACKGROUND

Several maternal conditions can affect fetal growth, and asthma during pregnancy is known to be associated with lower birth weight and shorter gestational age.

OBJECTIVE

In a new Swedish cohort study on maternal asthma exposure and stress during pregnancy (MAESTRO), we have assessed if there is evidence of early fetal growth restriction in asthmatic women or if a growth restriction might come later during pregnancy.

METHODS

We recruited women from eight antenatal clinics in Stockholm, Sweden. Questionnaires on background factors, asthma status and stress were assessed during pregnancy. The participants were asked to consent to collection of medical records including ultrasound measures during pregnancy, and linkage to national health registers. In women with and without asthma, we studied reduced or increased growth by comparing the second-trimester ultrasound with first-trimester estimation. We defined reduced growth as estimated days below the 10th percentile and increased growth as days above the 90th percentile. At birth, the weight and length of the newborn and the gestational age was compared between women with and without asthma.

RESULTS

We enrolled 1693 participants in early pregnancy and collected data on deliveries and ultrasound scans in 1580 pregnancies, of which 18% of the mothers had asthma. No statistically significant reduced or increased growth between different measurement points were found when women with and without asthma were compared; adjusted odds ratios for reduced growth between first and second trimester 1.11 95% CI (0.63-1.95) and increased growth 1.09 95% CI (0.68-1.77).

CONCLUSION AND CLINICAL RELEVANCE

In conclusion, we could not find evidence supporting an influence of maternal asthma on early fetal growth in the present cohort: Although the relatively small sample size, which may enhance the risk of a type II error, it is concluded that a potential difference is likely to be very small.

The Impact of the SARS-CoV-2 Pandemic on the Emergency Department and Management of the Pediatric Asthmatic Patient

INTRODUCTION

Asthma exacerbation is among the commonest causes for pediatric emergency room visits, and respiratory viruses are frequent triggers of such exacerbations. Few studies have evaluated the consequences of the novel human coronavirus that causes the illness currently known as COVID-19, in the pediatric population.

PURPOSE

The objective of this study was to analyze the impact of the COVID-19 pandemic and lockdown measures on the emergency department in the pediatric asthmatic patient.

PATIENTS AND METHODS

This retrospective observational study evaluated pediatric patients treated at the Pediatric Emergency Service for wheezing episodes. Changes in the number and characteristics of these patients over the same period of 2019 as compared to 2020 during the month following the alarm declaration (March 14 to April 15) were evaluated.

RESULTS

In total, data of 30 asthma patients managed in the period after the declaration of the coronavirus pandemic and of 158 asthma patients managed in the pre-COVID-19 period were included. In 2020, patient visits decreased by 82% in 2019. No statistically significant differences among age, sex, oxygen saturation, fever status, or number of severe bronchospasm episodes were found. Nebulized medication usage was reduced significantly since the alarm declaration. No significant increase in requests for complementary testing in the COVID-19 period was found. No patient requiring hospital admission was found to be PCR SARS-CoV-2 positive. Median time spent in the emergency department decreased from 180 minutes in 2019 to 85 minutes in the COVID-19 era.

CONCLUSION

The COVID-19 pandemic and ensuing lockdown measures have led to an extraordinary reduction in emergency visits to the pediatric service. The ongoing pandemic has also led to improvements in the approach to asthma exacerbations and wheezing, to reduce the risk of exposure to the virus, such as increased use of pressurized metered dose inhaler and decreased time in the Emergency Department.

Nuclear Receptors in Asthma: Empowering Classical Molecules Against a Contemporary Ailment

The escalation in living standards and adoption of 'Western lifestyle' has an allied effect on the increased allergy and asthma burden in both developed and developing countries. Current scientific reports bespeak an association between allergic diseases and metabolic dysfunction; hinting toward the critical requirement of organized lifestyle and dietary habits. The ubiquitous nuclear receptors (NRs) translate metabolic stimuli into gene regulatory signals, integrating diet inflences to overall developmental and physiological processes. As a consequence of such promising attributes, nuclear receptors have historically been at the cutting edge of pharmacy world. This review discusses the recent findings that feature the cardinal importance of nuclear receptors and how they can be instrumental in modulating current asthma pharmacology. Further, it highlights a possible future employment of therapy involving dietary supplements and synthetic ligands that would engage NRs and aid in eliminating both asthma and linked comorbidities. Therefore, uncovering new and evolving roles through analysis of genomic changes would represent a feasible approach in both prevention and alleviation of asthma.

Extrafine triple therapy and asthma exacerbation seasonality: TRIMARAN and TRIGGER post hoc analyses

BACKGROUND

Previous studies have shown seasonal variation in asthma exacerbations, peaking over the winter months. A single-inhaler triple therapy containing extrafine formulations of the inhaled corticosteroid (ICS) beclomethasone dipropionate (BDP), long-acting β₂-agonist formoterol fumarate (FF), and long-acting muscarinic antagonist glycopyrronium (G) is in development for asthma.

OBJECTIVE

We sought to evaluate whether calendar season impacted the relative effect of BDP/FF/G versus BDP/FF on moderate and severe asthma exacerbations.

METHODS

TRIMARAN and TRIGGER were double-blind 52-week studies comparing BDP/FF/G with BDP/FF (TRIMARAN medium-dose ICS; TRIGGER high-dose) in adults with uncontrolled asthma (Asthma Control Questionnaire-7 score ≥1.5), prebronchodilator FEV₁ less than 80% predicted, history of 1 or more asthma exacerbation, who had been receiving ICS/long-acting β₂-agonist for at least 4 weeks before entry. Moderate and severe asthma exacerbations were captured throughout each study. In these post hoc analyses, the annual moderate and severe exacerbation rate was calculated for each month, with rate ratios determined from events grouped by season.

RESULTS

In patients who received BDP/FF alone, there was a marked seasonal effect on the occurrence of asthma exacerbations, with the rate highest in the winter months. However, the addition of the long-acting muscarinic antagonist component to BDP/FF reduced this seasonal variation, especially during the winter, such that the relative effect of BDP/FF/G versus BDP/FF was greatest in the winter (significant 20.3% reduction [P = .0008]). Reductions in the other seasons ranged between 8.6% and 12.0%.

CONCLUSIONS

These post hoc analyses indicate that inhaled triple therapy with extrafine BDP/FF/G reduces seasonal peaks in moderate and severe exacerbations, and confirm the overall utility of adding long-acting muscarinic antagonist to ICS/long-acting β₂-agonist in the management of asthma.

Determination of the cutoff values of Th2 markers for the prediction of future exacerbation in severe asthma: An analysis from the Hokkaido Severe Asthma Cohort Study

BACKGROUND

We recently reported that severe asthma patients with frequent exacerbations showed high blood eosinophil counts (Eo) and fractions of exhaled nitric oxide (FeNO) compared with non-exacerbators. However, we did not determine exact cutoff values related to exacerbation. The aim of this study was to determine the cutoff values of Eo and FeNO that could be related to the exacerbation of severe asthma. We also aimed to confirm the clinical utility of Th2 markers related to exacerbation.

METHODS

This study included 105 severe asthma patients who completed a three-year follow-up of a severe asthma cohort study, including smokers. Three Th2 markers were selected, viz., Eo, FeNO, and positive atopic status. Regarding Eo and FeNO, we determined the cutoff values for the definition of "positive" Th2 features using receiver operating characteristic curve analyses, based on the comparisons between frequent exacerbators and other patients.

RESULTS

The cutoff values for positive Th2 features were Eo ≥ 250 cells/μL and FeNO ≥31 ppb. Sixteen patients (15.2%) had no Th2 features, 40 (38.1%) had one, 25 (23.8%) had two, and 24 (22.9%) had three. A high number of positive Th2 features was significantly associated with exacerbation frequencies over three years (p < 0.05). Similarly, compared to patients with one or no Th2 features, those with three Th2 features had a significantly higher probability of having more than one exacerbation (p < 0.05).

CONCLUSIONS

The cutoff values determined in the current analysis were good predictors of future exacerbations in severe asthma patients.

Rhinovirus and asthma: Challenges and opportunities

Human rhinoviruses (RVs) are the primary aetiological agent of the common cold. Generally, the associated infection is mild and self‐limiting, but may also be associated with bronchiolitis in infants, pneumonia in the immunocompromised and exacerbation in patients with pulmonary conditions such as asthma or chronic obstructive pulmonary disease. Viral infection accounts for as many as two thirds of asthma exacerbations in children and more than half in adults. Allergy and asthma are major risk factors for more frequent and severe RV‐related illnesses. The prevalence of RV‐induced wheezing will likely continue to increase given that asthma affects a significant proportion of the population, with allergic asthma accounting for the majority. Several new respiratory viruses and their subgroups have been discovered, with various degrees of relevance. This review will focus on RV infection in the context of the epidemiologic evidence, genetic variability, pathobiology, clinical studies in the context of asthma, differences with other viruses including COVID‐19 and current treatment interventions.

Asthma attacks in children are always preceded by poor asthma control: myth or maxim?

Some, but not all, asthma exacerbations in children are preceded by poor asthma control https://bit.ly/3muIy6h.

Asthma exacerbations and worsenings in patients aged 1-75 years with add-on tiotropium treatment

This review explores the effect of tiotropium Respimat® add-on therapy on asthma exacerbations and worsenings, adverse events (AEs) related to exacerbations and symptoms and any effects on seasonality across the 10 UniTinA-asthma® clinical trials comprising over 6000 patients. When added on to inhaled corticosteroids ± additional therapies, tiotropium significantly reduced the risk of exacerbations and worsenings in adults with symptomatic severe asthma and provided a non-significant improvement in worsenings in adults with symptomatic moderate and mild asthma, which was significant for patients with moderate asthma receiving tiotropium 2.5 µg once daily vs. placebo. Trials in paediatric patients were not powered to assess exacerbations or worsenings, but when AEs related to asthma exacerbations and symptoms were grouped into a composite endpoint and pooled, tiotropium improved outcomes vs. placebo (rate ratio 0.76; 95% confidence interval 0.63, 0.93). The reduction in exacerbations with tiotropium is apparent across all patients during the observed seasonal peaks of these events.

Real-World Patterns of Pharmacotherapeutic Management of Asthma Patients With Exacerbations in the Spanish National Health System

Background

Little is known about the real1world characteristics of asthma patients with exacerbations or their pharmacotherapeutic management. We described the sociodemographic and clinical characteristics, and the patterns of short and long-term management of asthma attacks, in a population-wide cohort of exacerbators in the region of Valencia, Spain.

Methods

We selected asthma patients with at least one exacerbation in 2015 and 2016, we classified them according to their patterns of exacerbations in the 4 years previous to the index exacerbation and their therapeutic step at baseline based on medication received in the previous year. We described the short and long-term pharmacological management of the index exacerbation.

Results

18,714 patients experienced at least one exacerbation. The majority had no previous exacerbation (46.5%), or exacerbated in only one of the years (26.8%). 2.9% had attacks every single year, 25.7% of whom only received rescue medication at baseline. 29.5% of patients without previous exacerbation received maintenance therapy at baseline. Shortly following the index exacerbation, 2,461 patients (13.1%) did not receive any asthma prescription. Among those treated, 70.3% were prescribed a maintenance therapy, 62.4% received a rescue medication, and 30.5% received an oral corticoid. Throughout the year following the index exacerbation, most patients remained in their baseline therapeutic step.

Conclusions

Most patients that exacerbate present very mild to mild forms of the disease or low levels of treatment and most exacerbations are managed in primary care. These insights may help to refine strategies for improving asthma control in the population.

Emergency department visits and hospitalisations for emergent asthmatic symptoms from 2014 to 2016: cross-sectional study in Korea

OBJECTIVE

To evaluate the characteristics of emergent patients with asthma who visited emergency departments (EDs) in Korea, and the consequences of these visits.

DESIGN

Retrospective cross-sectional study.

SETTING

We used data from the National Emergency Department Information System database from 2014 to 2016. The data included reports collected from 408 EDs in Korea.

PARTICIPANTS

We analysed the ED cases for asthma-related emergent symptoms that met the following inclusion criteria: (1) had a main diagnosis code of asthma (International Classification of Diseases 10th Revision code: J45/J46), and (2) recorded as an emergent symptom in the EDs.

RESULTS

During 2014-2016, there were 58 713 ED visits related to an asthma diagnosis with emergent symptoms. Following an ED visit, 31.69% were hospitalised, of which 89.88% were admitted to the general wards, and 10.12% to the intensive care units (ICUs). More than 50% of the hospitalised cases included in the group ≥70 years of age. The incidence of death during hospitalisation generally increased with age and the proportion of death in ICU exceeded 10% among the group ≥70 years. The ratio of ICU/general ward admission at the arrival time of 0-03:00, in the ≥60 years age group was the highest compared with other times of the day and age groups.

CONCLUSIONS

We found that among all age groups, ED visits by older patients resulted in more ICU admissions. Our results can help in providing a better understanding of medical resource utilisation by emergent patients with asthma.

Prevalence and characterization of asthma in hospitalized and nonhospitalized patients with COVID-19

Background

The Centers for Disease Control and Prevention advises that patients with moderate to severe asthma belong to a high-risk group that is susceptible to severe coronavirus disease 2019 (COVID-19). However, the association between asthma and COVID-19 has not been well-established.

Objective

The primary objective was to determine the prevalence of asthma among patients with COVID-19 in a major US health system. We assessed the clinical characteristics and comorbidities in asthmatic and nonasthmatic patients with COVID-19. We also determined the risk of hospitalization associated with asthma and/or inhaled corticosteroid use.

Methods

Medical records of patients with COVID-19 were searched by a computer algorithm (March 1 to April 15, 2020), and chart review was used to validate the diagnosis of asthma and medications prescribed for asthma. All patients had PCR-confirmed COVID-19. Demographic and clinical features were characterized. Regression models were used to assess the associations between asthma and corticosteroid use and the risk of COVID-19–related hospitalization.

Results

Of 1526 patients identified with COVID-19, 220 (14%) were classified as having asthma. Asthma was not associated with an increased risk of hospitalization (relative risk, 0.96; 95% CI, 0.77-1.19) after adjusting for age, sex, and comorbidities. The ongoing use of inhaled corticosteroids did not increase the risk of hospitalization in a similar adjusted model (relative risk, 1.39; 95% CI, 0.90-2.15).

Conclusions

Despite a substantial prevalence of asthma in our COVID-19 cohort, asthma was not associated with an increased risk of hospitalization. Similarly, the use of inhaled corticosteroids with or without systemic corticosteroids was not associated with COVID-19–related hospitalization.

Ambient pollen concentrations and asthma hospitalization in children and adolescents: a systematic review and meta-analysis

ObjectiveWe aimed to conduct a systematic review examining the association between outdoor pollen and childhood asthma hospitalizations.Data SourceA systematic search of articles in MEDLINE, EMBASE, CINAHL, ProQuest Central, Web of Science and Google Scholar published to 18 July 2019.Study selection: Studies that presented data on pollen exposure and childhood asthma hospitalization were included and evaluated for potential risk of bias by two independent authors. Random effects meta-analysis was performed where possible.ResultsA total of 1048 records were identified, and twelve studies included in the review. The synthesis suggested possible associations between outdoor pollen, especially for grass and birch and childhood asthma hospitalization. However, the results varied widely across geographical areas and settings for other pollen taxa. The meta-analysis of the case-crossover studies showed a positive association between grass and childhood asthma hospitalization, an increase in 10 grass pollen grains/m³ was associated with a 3% increase in childhood asthma admission (OR = 1.03; 95%CI:1.01, 1.04), but the pooled estimate was not significant for timeseries studies. The meta-analysis of the timeseries studies for birch pollen showed an increase in 10 pollen grains/m³ being significantly associated with a Mean Percentage Change (MPC) in childhood asthma admissions (MPC= 0.85; 95%CI:0.40, 1.30).Conclusion: Globally, grass and birch pollen are important triggers of childhood asthma hospitalization, but the association could not be ascertained for other pollen taxa. Pollen is a major environmental trigger of asthma exacerbations and more focus on early interventions to reduce this burden needs to be considered.

Is Ascaris lumbricoides a risk factor for development of asthma? A systematic review and meta-analysis

There are numerous epidemiological and experimental evidences to suggest that Ascaris lumbricoides infection is a neglected risk factor for development of asthma. For this purpose, we conducted a systematic review and meta-analysis for better understanding of this relationship. Systematic searching (PubMed, Scopus, Web of Science and Google Scholar) was done, up to September 30, 2019 to identify the relevant studies. We applied random-effects meta-analysis model to generate the overall odds ratio (OR) and 95% confidence intervals (CIs). Heterogeneity was assessed with I2 and τ2 statistic. Finally, 19 studies (totally 25 datasets), including 14 datasets with microscopic methods (1830 asthmatic patients (APs) and 3802 healthy controls (HCs)) and 11 datasets with serological methods (1543 APs and 3507 HCs) met the eligibility criteria. Considering to the serological methods, our results demonstrated that the APs had higher seroprevalence rate of A. lumbricoides (48.3% vs. 35.1%) than HCs, showing a significant association (pooled crude OR, 1.53; 95%CI, 1.07-2.18). Moreover, microscopic methods showed a higher prevalence of A. lumbricoides infection in the APs compared to the HCs (37.2% vs. 30.2%), but no significant association was found between APs and HCs (pooled crude OR, 1.19; 95%CI, 0.92-1.55). After adjustment for confounders, results showed no significant association for both serological (pooled adjusted OR, 1.43; 95%CI, 0.93-2.19) and microscopic (pooled adjusted OR, 1.05; 95%CI, 0.78-1.42) methods. Despite heterogeneous results, accurate and better quality studies are needed to determine the effect of A. lumbricoides infection on induction or exacerbation of asthma.

Recent advances in the detection of respiratory virus infection in humans

Respiratory tract viral infection caused by viruses or bacteria is one of the most common diseases in human worldwide, while those caused by emerging viruses, such as the novel coronavirus, 2019‐nCoV that caused the pneumonia outbreak in Wuhan, China most recently, have posed great threats to global public health. Identification of the causative viral pathogens of respiratory tract viral infections is important to select an appropriate treatment, save people's lives, stop the epidemics, and avoid unnecessary use of antibiotics. Conventional diagnostic tests, such as the assays for rapid detection of antiviral antibodies or viral antigens, are widely used in many clinical laboratories. With the development of modern technologies, new diagnostic strategies, including multiplex nucleic acid amplification and microarray‐based assays, are emerging. This review summarizes currently available and novel emerging diagnostic methods for the detection of common respiratory viruses, such as influenza virus, human respiratory syncytial virus, coronavirus, human adenovirus, and human rhinovirus. Multiplex assays for simultaneous detection of multiple respiratory viruses are also described. It is anticipated that such data will assist researchers and clinicians to develop appropriate diagnostic strategies for timely and effective detection of respiratory virus infections.

Respiratory tract viral infection including 2019‐nCoV poses great threats worldwide. Currently available and novel emerging diagnostic methods are summarized for several common respiratory viruses, including influenza virus, human respiratory syncytial virus, coronavirus, human adenovirus and human rhinovirus. Multiplex assays for simultaneous detection of multiple respiratory viruses are also described. This review is aimed to assist researchers and clinicians to develop timely and effective diagnostic strategies to detect respiratory virus infections.

Crop burning and the prevalence of asthma and COPD emergency department treatments in a rural Arkansas county

OBJECTIVE

To evaluate the impact of crop burning on the prevalence of asthma and COPD emergency department (ED) treatments in a rural Arkansas county.

METHODS

Administrative datasets listing ED treatments for asthma and COPD obtained from the Arkansas Hospital Discharge Dataset System for the calendar years 2014-2016 were used in this semi-ecological study. Primary diagnosis codes (ICD-9: 490-496 and ICD-10: J40-J47) were used to identify patients who were diagnosed with asthma and COPD. Patients with a reported county of residence in Craighead County were determined as case county residents and those in Sebastian County were control county residents. Month of visit was used to determine seasonal variation. PM 2.5 air quality data were obtained from the EPA AQS Data Mart.

RESULTS

Between 2014 through 2016, there were a combined total of 2,536 ED treatments due to asthma and 8,530 due to COPD in Craighead and Sebastian counties. The odds of being treated in the ED during the fall months for asthma and COPD are associated with a 20.9% increase and 16.9% increase respectively in Craighead County as compared to Sebastian Country after adjusting for potential confounders (p = 0.04, p = 0.003). PM 2.5 concentrations were higher in Craighead County than Sebastian County during the fall season (p = 0.005).

CONCLUSION

Fall ED treatments for asthma and COPD were higher in Craighead County, Arkansas compared to Sebastian County, Arkansas for the years 2014-2016. PM 2.5 levels were also higher in Craighead County in the fall during these years. These differences may be attributable to crop burning.​.

Exacerbation Patterns in Adults with Asthma in England. A Population-based Study

RATIONALE

Asthma is heterogeneous and knowledge on exacerbation patterns is lacking. Previous studies have had a relatively short follow-up or focused on severe disease.

OBJECTIVES

To describe exacerbation patterns over a prolonged follow-up in a population that includes patients of all disease severity.

METHODS

We used electronic health care records to identify patients with asthma aged 18-55 years and their exacerbations from 2007 to 2015. A cohort with greater than or equal to 7 years of data was used to describe exacerbation patterns by asthma severity defined by medication use. Effect estimates for risk factors were calculated for sporadic (single year of exacerbations) and recurrent (>1 yr) exacerbation patterns, using logistic regression. In a nested case-control design, the association between a history of exacerbations, spanning 5 years, and a future exacerbation was examined.

MEASUREMENTS AND MAIN RESULTS

A total of 51,462 patients were eligible for the 7-year cohort; 64% had no exacerbations. Of those who exacerbated, 51% did so only once; exacerbation frequency increased with disease severity. Only 370 patients (0.7%) were characterized by a frequent-exacerbator phenotype (yearly exacerbations), of whom 58% had mild/moderate asthma. Exacerbation risk factors were not uniquely associated with a particular exacerbation pattern. A past exacerbation increased the risk of a future exacerbation more than all other factors, although this effect dissipated over 5 years.

CONCLUSIONS

During 7 years of follow-up, exacerbations occur in around one-third of patients. Of those who exacerbate, half do not do so again; the timing of future exacerbations is largely unpredictable. Just 2% exhibit a frequent-exacerbator phenotype. Past exacerbation patterns are the most informative risk factor for predicting future exacerbations.

Mechanisms and Management of Asthma Exacerbations

Acute asthma remains an important medical emergency, the most frequent cause of acute admissions in children and a major source of morbidity for adults with asthma. In all ages with asthma, the presence of exacerbations is an important defining characteristic of asthma severity. In this review, we assess the epidemiology of acute asthma, the triggers of acute exacerbations, and the mechanisms that underlie these exacerbations. We also assess current treatments that prevent exacerbations, with an emphasis on the role of type 2 airway inflammation in the context of acute exacerbations and the novel treatments that effectively target this. Finally we review current management strategies of the exacerbations themselves.