Asthma outcomes: exacerbations

Clinical and inflammatory features of traffic-related diesel exposure in children with asthma

BACKGROUND

Epidemiologic studies have revealed associations between traffic-related pollutants such as diesel particulate matter (PM) and asthma outcomes in children, but the inflammatory features associated with diesel PM exposure in children with asthma are not understood.

OBJECTIVE

To evaluate symptoms, exacerbations, and lung function measures in children with uncontrolled asthma and their associations with residential proximity to major roadways and to determine associations between diesel PM exposure and systemic inflammatory cytokines, circulating markers of T-cell activation and exhaustion, and metabolomic features using biomarker studies.

METHODS

Children 5 to 17 years of age with physician-diagnosed, uncontrolled asthma despite treatment with an asthma controller medication completed a research visit involving questionnaires, lung function testing, and venipuncture for biomarker studies. Geocoding was performed to quantify residential proximity to major roadways and pollutant exposure.

RESULTS

A total of 447 children with uncontrolled asthma were enrolled. Children living closer to highly trafficked roadways were more disadvantaged and had more exposure to diesel PM, more exacerbations prompting an emergency department visit, and lower lung function measures. Children with the highest diesel PM exposure, compared with children with the lowest diesel PM exposure, also had blunted cytokine secretion and evidence of T-cell exhaustion, including disturbances in several metabolites associated with glutathione formation and oxidative stress.

CONCLUSION

Traffic-related diesel PM exposure in children with poorly controlled asthma is associated with poorer clinical outcomes and unique patterns of inflammation and oxidative stress. These findings argue for continued mitigation efforts to improve traffic-related air quality and health equity in children with asthma.

Temporal variation in the effectiveness of biologics in asthma: Effect modification by changing patient characteristics

BACKGROUND

The underlying population of patients selected for each respiratory monoclonal antibody might change as other biologics are approved.

OBJECTIVE

To evaluate effect modification by calendar time of the effectiveness of each respiratory biologics in asthma.

METHODS

The Effectiveness of Respiratory biologics in Asthma (ERA) is a retrospective cohort of severe asthma patients from the Mass General Brigham clinics between January 2013 and September 2023. Periods were pre-specified as the anti-IgE (2013-2015), anti-IL5 (2016-2018), anti-IL4/13 (2019-2021) or anti-alarmin (2022-2023) era. We evaluated each biologic's effect on asthma-related exacerbations comparing the one-year period before and after therapy initiation using Poisson regression and Cox regression for time-to-first exacerbation.

RESULTS

Of 647 biologic-naïve patients, 165 initiated omalizumab, 235 anti-IL5, 227 dupilumab, and 20 tezepelumab. Omalizumab's effectiveness improved as more biologics were approved: incidence rate ratio (IRR) 1.16 [0.94-1.43] anti-IgE era vs. 0.54 [0.37-0.80] anti-IL4/13-alarmin era. Omalizumab patients in the anti-IL4/13-alarmin era had lower blood eosinophil counts and less chronic rhinosinusitis with nasal polyps (CRSwNP). For anti-IL5s, effectiveness peaked in the anti-IL4/13 era (IRR 0.52 [0.42-0.64]) when patients had higher BMI and less concomitant CRSwNP. Dupilumab was most effective in the anti-IL4/13 era (IRR 0.60 [0.50-0.72]). There were fewer current smokers in dupilumab patients in the anti-IL4/13 era. Results were similar in time-to-event analyses and in sensitivity analyses accounting for the COVID-19 pandemic.

CONCLUSION

There are temporal variations in the effectiveness of biologics partly explained by the shift in the underlying population, particularly for omalizumab. Though having more choices was associated with better patient selection for omalizumab, this was inconsistent for other biologics.

Do respiratory virus infections modify associations of asthma exacerbation with aeroallergens or fine particulate matter? A time series study in Philadelphia PA

Respiratory virus infections are related to over 80% of childhood asthma exacerbations. They enhance pro-inflammatory mediator release, especially for sensitized individuals exposed to pollens/molds. Using a time-series study design, we investigated possible effect modification by respiratory virus infections of the associations between aeroallergens/PM2.5 and asthma exacerbation rates. Outpatient, emergency department (ED), and inpatient visits for asthma exacerbation among children with asthma (28,540/24,444 [warm/cold season]), as well as viral infection counts were obtained from electronic health records of the Children's Hospital of Philadelphia from 2011 to 2016. Rate ratios (RRs, 90th percentile vs. 0) for late-season grass pollen were 1.00 (0.85-1.17), 1.04 (0.95-1.15), and 1.12 (0.96-1.32), respectively, for respiratory syncytial virus (RSV) counts within each tertile. However, similar trends were not observed for weed pollens/molds or PM2.5. Overall, our study provides little evidence supporting effect modification by respiratory viral infections.

Short-acting β2-agonists (SABA) overuse in asthma and patients' perceptions for this behavior

BACKGROUND

Short-acting β2-agonists (SABA) overuse is associated with poor asthma control. The Global Initiative for Asthma (GINA) 2019-updated strategy report has therefore taken a paradigm shift in reliever therapy recommendations.

OBJECTIVES

(I) To investigate the status of SABA overuse and medication dispensing patters in asthma in the Netherlands (II) validate dispensing data for SABA overuse identification and (III) understand patients' perspectives towards this SABA-taking behavior to inform future improvement strategies.

METHODS

An annually repeated cross-sectional study was conducted from 2017 to 2021 using pharmacy dispensing data in a real-world setting, including asthma patients aged 18-45 with ≥1 inhaler. A following qualitative study was performed in identified SABA overusing patients with a questionnaire and semi-structured interviews, supported by theoretical frameworks.

RESULTS

Dispensing data was available from 87 % of all community pharmacies (n = 1994) in 2017 and 95 % (n = 2005) in 2021. SABA overuse prevalence was constant for the five study-years with 20.6 % (±0.5 %). Increased ICS-formoterol and decreased SABA dispenses were observed in starters of inhalation therapy in 2021. 53 asthma patients completed the questionnaire of whom 43 patients confirmed SABA overuse, generating a positive predictive value of 81 %. Key behavioral drivers covered 7 themes regarding capability (knowledge; skills; memory, attention and decision process) motivation (emotion; beliefs about-capabilities; consequences) and opportunity (environmental context).

CONCLUSION

SABA overuse remains in one-fifth of asthma patients across the Netherlands, requiring careful attention from healthcare professionals. Dispensing data is a valid measure for SABA overuse in a clinical setting, facilitating patient selection. To meet patients' varied supporting needs, integration of tailored behavioral interventions is essential.

Amygdalar involvement in respiratory dysfunction

The brainstem has long been recognized as the major respiratory control center, but it has become increasingly appreciated that areas upstream of the brainstem modulate respiration and airway defensive behaviors. This review aims to define the role of the amygdala, a key temporal brain region essential for limbic function, in respiration and airway defenses. We summarize literature describing roles for the amygdala in control of respiration, swallow, cough, airway smooth muscle contraction, and mucus secretion. We emphasize the need to understand how the amygdala regulates these functions both at a local scale and network scale and identify knowledge gaps for current and future investigations. Lastly, we highlight literature suggesting that amygdala dysfunction may contribute to respiratory dysfunction.

Use of telerehabilitation platforms for delivering patient education among patients with asthma: a scoping review

OBJECTIVE

Use of tele-technology for monitoring symptoms, functional parameters, and quality-of-life of people with asthma is essential. Delivering this information among patients is mandated for a better outcome and made possible via patient education (PE). This review aims to summarize the types of telerehabilitation modalities, dosage, and outcome measures used to assess the effectiveness of PE among people with asthma.

METHODS

We adopted a scoping review methodology. Thematic analysis was used to synthesize the data. The Preferred Reporting System for Meta-Analysis for Scoping Reviews (PRISMA-ScR) was followed during the review process.

RESULTS

PubMed, Embase, and Scopus were searched, with 34 studies meeting inclusion criteria. Results are presented in three themes: telerehabilitation platforms used to deliver PE among patients with asthma; content, duration, and frequency of the PE administered; and patient-reported outcome measures used to evaluate the effectiveness of PE.

CONCLUSION

This scoping study detailed the types of telerehabilitation modalities, dosage, and outcome measures used to assess the effectiveness of PE in people with asthma. This review will be especially beneficial to those considering where additional research or implementation of telerehabilitation for asthma patients is required. The studies emphasized the involvement of several healthcare experts, emphasizing the significance of a multidisciplinary approach to efficient PE delivery and possible improvements in asthma management through telerehabilitation. Although a range of telerehabilitation platforms were generally accepted, hybrid models that integrate online and in-person sessions could further enhance patient satisfaction and quality-of-life. Comprehensive economic analyses are also required, and solving technology issues is essential to maximizing the efficacy of these initiatives.

Outdoor aeroallergen impacts on asthma exacerbation among sensitized and nonsensitized Philadelphia children

Background

Outdoor aeroallergens, such as pollens and molds, are known triggers of asthma exacerbation; however, few studies have examined children's aeroallergen response based on sensitization.

Objective

Our aim was to compare the relative impact of aeroallergen levels on asthma exacerbation between pediatric patients with asthma who tested positive or negative for sensitization to particular allergens.

Methods

A case-crossover design study was conducted to examine associations between outdoor aeroallergen levels and asthma exacerbation events among children living in Philadelphia, Pennsylvania, who were treated within a large pediatric care network. Sensitization to common allergens was characterized in a subset of patients with asthma exacerbation who had undergone skin prick testing (5.5%). Odds ratios (ORs) and 95% CIs were estimated in all patients with asthma exacerbation and in those sensitized or not sensitized to aeroallergens.

Results

Children who were sensitized to a particular allergen had higher odds of asthma exacerbation with exposure to the allergen (ie, early-season tree pollen, oak tree pollen, early-season weed pollen, and late-season molds) than did all patients with asthma or nonsensitized patients. For example, the association between early-season tree pollen and asthma exacerbation among sensitized children (>90th percentile vs ≤25th, OR = 2.28 [95% CI = 1.23-4.22]) was considerably stronger than that estimated among all patients (OR = 1.34 [95% CI = 1.19-1.50]), and it was also substantially different from the lack of association seen among nonsensitized children (OR = 0.89 [95% CI = 0.51-1.55] [P value for heterogeneity = .03]).

Conclusion

More prevalent allergy testing may be useful for prevention of asthma exacerbation by informing interventions targeted to sensitized children and tailored for particular aeroallergens.

Association of Novel Antihyperglycemic Drugs Versus Metformin With a Decrease in Asthma Exacerbations

BACKGROUND

Similar to metformin, dipeptidyl peptidase-4 inhibitors (DPP-4 Is), glucagon-like peptidase 1 receptor agonists (GLP-1 RAs), and sodium glucose co-transporter-2 inhibitors (SGLT-2 Is) may improve control of asthma owing to their multiple potential mechanisms, including differential improvements in glycemic control, direct anti-inflammatory effects, and systemic changes in metabolism.

OBJECTIVE

To investigate whether these novel antihyperglycemic drugs were associated with fewer asthma exacerbations compared with metformin in patients with asthma comorbid with type 2 diabetes.

METHODS

Using a Japanese national administrative database, we constructed 3 active comparators-new user cohorts of 137,173 patients with a history of asthma starting the novel antihyperglycemic drugs and metformin between 2014 and 2022. Patient characteristics were balanced using overlap propensity score weighting. The primary outcome was the first exacerbation requiring systemic corticosteroids, and the secondary outcomes included the number of exacerbations requiring systemic corticosteroids.

RESULTS

DPP-4 Is and GLP-1 RAs were associated with a higher incidence of exacerbations requiring systemic corticosteroids compared with metformin (DPP-4 Is: 18.2 vs 17.4 per 100 person-years, hazard ratio: 1.09, 95% confidence interval [CI]: 1.05-1.14; GLP-1 RAs: 24.9 vs 19.0 per 100 person-years, hazard ratio: 1.14, 95% CI: 1.01-1.28). In contrast, the incidence of exacerbations requiring systemic corticosteroids was similar between the SGLT-2 Is and metformin groups (17.3 vs 18.1 per 100 person-years, hazard ratio: 1.00, 95% CI: 0.97-1.03). While DPP-4 Is and GLP-1 RAs were associated with more exacerbations requiring systemic corticosteroids, SGLT-2 Is were associated with slightly fewer exacerbations requiring systemic corticosteroids (53.7 vs 56.6 per 100 person-years, rate ratio: 0.95, 95% CI: 0.91-0.99).

CONCLUSIONS

While DPP-4 Is and GLP-1 RAs were associated with poorer control of asthma compared with metformin, SGLT-2 Is offered asthma control comparable to that of metformin.

A Simulation Study of the Effect of Clinical Characteristics and Treatment Choice on Reliever Medication Use, Symptom Control and Exacerbation Risk in Moderate-Severe Asthma

INTRODUCTION

The relationship between immediate symptom control, reliever medication use and exacerbation risk on treatment response and factors that modify it have not been assessed in an integrated manner. Here we apply simulation scenarios to evaluate the effect of individual baseline characteristics on treatment response in patients with moderate-severe asthma on regular maintenance dosing monotherapy with fluticasone propionate (FP) or combination therapy with fluticasone propionate/salmeterol (FP/SAL) or budesonide/formoterol (BUD/FOR).

METHODS

Reduction in reliever medication use (puffs/24 h), change in symptom control scores (ACQ-5), and annualised exacerbation rate over 12 months were simulated in a cohort of patients with different baseline characteristics (e.g. time since diagnosis, asthma control questionnaire (ACQ-5) symptom score, smoking status, body mass index (BMI) and sex) using drug-disease models derived from large phase III/IV clinical studies.

RESULTS

Simulation scenarios show that being a smoker, having higher baseline ACQ-5 and BMI, and long asthma history is associated with increased reliever medication use (p < 0.01). This increase correlates with a higher exacerbation risk and higher ACQ-5 scores over the course of treatment, irrespective of the underlying maintenance therapy. Switching non-responders to ICS monotherapy to combination therapy after 3 months resulted in immediate reduction in reliever medication use (i.e. 1.3 vs. 1.0 puffs/24 h for FP/SAL and BUD/FOR, respectively). In addition, switching patients with ACQ-5 > 1.5 at baseline to FP/SAL resulted in 34% less exacerbations than those receiving regular dosing BUD/FOR (p < 0.01).

CONCLUSIONS

We have identified baseline characteristics of patients with moderate to severe asthma that are associated with greater reliever medication use, poor symptom control and higher exacerbation risk. Moreover, the effects of different inhaled corticosteroid (ICS)/long-acting beta agonist (LABA) combinations vary significantly when considering long-term treatment performance. These factors should be considered in clinical practice as a basis for personalised management of patients with moderate-severe asthma symptoms.

Untargeted metabolomic analysis reveals different metabolites associated with response to mepolizumab and omalizumab in asthma

Background

There is limited evidence on biomarkers associated with response to the monoclonal antibodies currently approved for asthma treatment. We sought to identify circulatory metabolites associated with response to treatment with mepolizumab or omalizumab.

Methods

We conducted global metabolomic profiling of pre-treatment plasma samples from 100 patients with moderate-to-severe asthma who initiated mepolizumab (n=31) or omalizumab (n=69). The primary outcome was the change in exacerbations within 12 months of therapy. Negative binomial models were used to assess the association between each metabolite and exacerbations, adjusting for age, sex, body mass index, baseline exacerbations and inhaled corticosteroid use. Chemical similarity enrichment analysis (ChemRICH) was conducted to identify chemical subclasses associated with treatment response.

Results

The mean age of the mepolizumab group was 58.7 years with on average 2.9 exacerbations over the year prior to initiation of biologic therapy. The mean age in the omalizumab group was 48.8 years with 1.5 exacerbations in the preceding year. Patients with higher levels of two tocopherol metabolites were associated with more exacerbations on mepolizumab (δ-carboxyethyl hydroxychroman (CEHC) (p=2.65E-05, false discovery rate (FDR=0.01) and δ-CEHC glucuronide (p=2.47E-06, FDR=0.003)). Higher levels of six androgenic steroids, three carnitine metabolites and two bile acid metabolites were associated with decreased exacerbations in the omalizumab group. In enrichment analyses, xanthine metabolites (cluster FDR=0.0006) and tocopherol metabolites (cluster FDR=0.02) were associated with worse mepolizumab response, while androgenic steroids (cluster FDR=1.9E-18), pregnenolone steroids (cluster p=3.2E-07, FDR=1.4E-05) and secondary bile acid metabolites (cluster p=0.0003, FDR=0.006) were the top subclasses associated with better omalizumab response.

Conclusion

This study identifies distinct metabolites associated with response to mepolizumab and omalizumab, with androgenic steroids associated with response to both mepolizumab and omalizumab.

The Child Opportunity Index 2.0 and exacerbation-prone asthma in a cohort of urban children

RATIONALE

Social determinants of health underlie disparities in asthma. However, the effects of individual determinants likely interact, so a summary metric may better capture their impact. The Child Opportunity Index 2.0 (COI) is one such tool, yet its association with exacerbation-prone (EP) asthma is unknown.

OBJECTIVE

To investigate the association between the COI and EP asthma and clinical measures of asthma severity in children.

METHODS

We analyzed data from two prospective observational pediatric asthma cohorts (n = 193). Children were classified as EP (≥1 exacerbation in the past 12 months) or exacerbation-null (no exacerbations in the past 5 years). Spirometry, exhaled nitric oxide, IgE, and Composite Asthma Severity Index (CASI) were obtained. The association between COI and EP status was assessed with logistic regression. We fit linear and logistic regression models to test the association between COI and each clinical measure.

RESULTS

A 20-point COI decrease conferred 40% higher odds of EP asthma (OR 1.4; 95%CI 1.1-1.76). The effect was similar when adjusted for age and sex (OR 1.38, 95%CI 1.1-1.75) but was attenuated with additional adjustment for race and ethnicity (OR 1.19, 95%CI 0.92-1.54). A similar effect was seen for the Social/Economic and Education COI domains but not the Health/Environment Domain. A 20-point COI decrease was associated with an increase in CASI of 0.34. COI was not associated with other clinical measures.

CONCLUSIONS

Lower COI was associated with greater odds of EP asthma. This highlights the potential use of the COI to understand neighborhood-level risk and identify community targets to reduce asthma disparities.

Incidence of New Asthma in Pregnancy and Associated Risk Factors: A 10-Year Nationwide Population-Based Study

Pregnancy is a risk factor for asthma exacerbation and may trigger new-onset asthma in nonasthmatics. This study evaluated the epidemiology of newly diagnosed asthma during pregnancy and the associated risk factors among previously nonasthmatic women. Twelve-year medical data from the Korean National Health Insurance claims database (from January 2007 to December 2018) of Korean women who gave birth between January 2012 and December 2015 were collected. Previously nonasthmatic women were defined as those who had not been diagnosed with asthma for at least 4 years before pregnancy. Asthma flare-up was defined as asthma diagnosed three times or more and treated at least once with an oral corticosteroid. A nested case-control study was performed, and then the derived risk factors were applied to whole study population. Among the nonasthmatic women, 7.5% experienced asthma during pregnancy including episodes requiring hospitalization and 18.6% of them visited emergency room. Older age, primiparity, multi-fetal pregnancy, and rhinitis were identified as the risk factors. Among the entire study population, moderate to severe rhinitis was a significant risk factor across all age groups, while primiparity with multi-fetal pregnancy was one for older pregnant women; 22.7% in those ≥ 34 years old experienced asthma flare-ups compared to only 3.5% in the < 34 age group. A substantial portion of pregnant women with no history of asthma experienced an asthma flare-up during pregnancy. Multi-fetal pregnancy as primiparity at a later age and moderate to severe rhinitis are risk factors for the new development of asthma.

Towards a patient-centred definition for atopic dermatitis flare: a qualitative study of adults with atopic dermatitis

BACKGROUND

The term 'flare' is used across multiple diseases, including atopic dermatitis (AD), to describe increased disease activity. While several definitions of an AD flare have been proposed, no single definition of AD flare is widely accepted and it is unclear what the term 'AD flare' means from the patient perspective.

OBJECTIVES

To understand AD flares from the adult patient perspective and to explore how adults with AD define an AD flare.

METHODS

Participants were adults with AD recruited from the National Eczema Association Ambassadors programme, a volunteer patient-engagement programme. They participated in online focus groups to discuss how they describe AD flares from their perspective, how they define its start and stop, and how they relate to existing definitions of flare. Using a grounded theory approach, transcripts were analysed and coded using an iterative process to identify concepts to support a patient-centred conceptual framework of 'flare'.

RESULTS

Six 90-min focus groups of 3-8 participants each were conducted with 29 US adults (≥ 18 years of age) with AD who had at least one self-reported AD flare in the past year. When participants were presented with examples of previously published definitions of AD flare, participants found them problematic and unrelatable. Specifically, they felt that flare is hard to quantify or put on a numerical scale, definitions cannot solely be about skin symptoms and clinical verbiage does not resonate with patients' lived experiences. Concepts identified by patients as important to a definition of flare were changes from patient's baseline/patient's normal, mental/emotional/social consequences, physical changes in skin, attention needed/all-consuming focus, itch-scratch-burn cycle and control/loss of control/quality of life. Figuring out the trigger that initiated a flare was an underlying concept of the experience of flare but was not considered a contributor to the definition.

CONCLUSIONS

The results highlight the complexity and diversity of AD flare experiences from the adult patient perspective. Previously published definitions of AD flares did not resonate with patients, suggesting a need for a patient-centred flare definition to support care conversations and AD management.

Comparative Effectiveness of Mepolizumab, Benralizumab, and Dupilumab among Patients with Difficult-to-Control Asthma: A Multicenter Retrospective Propensity-matched Analysis

Rationale: The comparative effectiveness of biologic agents used as add-on therapy in the management of difficult-to-control asthma is unclear. Objective: To compare the effectiveness of dupilumab, mepolizumab, and benralizumab among patients with difficult-to-control asthma. Methods: Retrospective multicenter cohort study of adult patients with difficult-to-control asthma starting treatment with dupilumab, mepolizumab, or benralizumab as documented in a multicenter electronic health record and claims-based database between October 19, 2018, and September 30, 2022. Propensity-score matching was used to minimize bias from nonrandomized treatment assignment; a prespecified α-level was set at 0.017 to account for three primary comparisons. The exposure of interest was the new initiation of dupilumab, benralizumab, or mepolizumab treatment. The primary outcome was the rate of asthma exacerbations in the 1 year after initiation of biologic therapy modeled using a negative binomial approach. Results: Among 893,668 patients with asthma who were prescribed an inhaled corticosteroid and were ⩾12 years old (65% female; mean age, 49 yr), 3,943 started dupilumab, 1,902 started benralizumab, and 2,012 started mepolizumab, all without an alternative indication for biologic therapy. After matching, there were 1,805 patients in each group for comparisons between dupilumab and benralizumab, 1,865 for comparisons between dupilumab and mepolizumab, and 1,721 for comparisons between mepolizumab and benralizumab. For all pairwise comparisons, covariates were well balanced after matching (all standardized mean differences <0.1). Patients who initiated dupilumab had a significantly lower rate of asthma exacerbations (1.07 per year) compared with benralizumab (1.47 per year), with a rate ratio (RR) of 0.73 (95% confidence interval, 0.63-0.85), and also had a significantly lower rate of asthma exacerbations compared with mepolizumab (1.04 per year vs. 1.45 per year), with an RR of 0.72 (0.62-0.84). There was no statistically significant difference in the rate of asthma exacerbations between mepolizumab (1.40 per year) and benralizumab (1.41 per year), with an RR of 1.00 (0.85-1.17). Conclusions: In patients with difficult-to-control asthma who had newly initiated biologic therapy, dupilumab was associated with a decreased rate of asthma exacerbations in the 1 year after initiation compared with mepolizumab or benralizumab.

Environmental Injustice Is Associated With Poorer Asthma Outcomes in School-Age Children With Asthma in Metropolitan Atlanta, Georgia

BACKGROUND

Environmental justice mandates that no person suffers disproportionately from environmental exposures. The Environmental Justice Index (EJI) provides an estimate of the environmental burden for each census tract but has not yet been used in asthma populations.

OBJECTIVE

We hypothesized that children from census tracts with high environmental injustice determined by the EJI would have a greater burden of asthma exacerbations, poorer asthma control, and poorer lung function over 12 months.

METHODS

Children aged 6 to 18 years with asthma (N = 575) from metropolitan Atlanta, Georgia, completed a baseline research visit. Participant addresses were geocoded to obtain the EJI Social-Environmental Ranking for each participant's census tract, which was divided into tertiles. Medical records were reviewed for 12 months for asthma exacerbations. A subset of participants completed a second research visit involving spirometry and questionnaires.

RESULTS

Census tracts with the greatest environmental injustice had more racial and ethnic minorities, lower socioeconomic status, more hazardous exposures (particularly to airborne pollutants), and greater proximity to railroads and heavily trafficked roadways. Children with asthma residing in high injustice census tracts had a longer duration of asthma, greater historical asthma-related health care utilization, poorer asthma symptom control and quality of life, and more impaired lung function. By 12 months, children from high injustice census tracts also had more asthma exacerbations with a shorter time to exacerbation and persistently more symptoms, poorer asthma control, and reduced lung function.

CONCLUSIONS

Disparities in environmental justice are present in metropolitan Atlanta that may contribute to asthma outcomes in children. These findings require an additional study and action to improve health equity.

The burden of severe asthma in sub-Saharan Africa: Findings from the African Severe Asthma Project

Background

Severe asthma is associated with high morbidity, mortality, and health care utilization, but its burden in Africa is unknown.

Objective

We sought to determine the burden (prevalence, mortality, and activity and work impairment) of severe asthma in 3 countries in East Africa: Uganda, Kenya, and Ethiopia.

Methods

Using the American Thoracic Society/European Respiratory Society case definition of severe asthma, we analyzed for the prevalence of severe asthma (requiring Global Initiative for Asthma [GINA] steps 4-5 asthma medications for the previous year to achieve control) and severe refractory asthma (remains uncontrolled despite treatment with GINA steps 4-5 asthma medications) in a cohort of 1086 asthma patients who had been in care for 12 months and had received all GINA-recommended medications. Asthma control was assessed by the asthma control questionnaire (ACQ).

Results

Overall, the prevalence of severe asthma and severe refractory asthma was 25.6% (95% confidence interval [CI], 23.1-28.3) and 4.6% (95% CI, 3.5-6.0), respectively. Patients with severe asthma were (nonsevere vs severe vs severe refractory) older (39, 42, 45 years, P = .011), had high skin prick test reactivity (67.1%, 76.0%, 76.0%, P = .004), had lower forced expiratory volume in 1 second percentage (81%, 61%, 55.5%, P < .001), had lower quality of life score (129, 127 vs 121, P < .001), and had higher activity impairment (10%, 30%, 50%, P < .001). Factors independently associated with severe asthma were hypertension comorbidity; adjusted odds ratio 2.21 (1.10-4.47), P = .027, high bronchial hyperresponsiveness questionnaire score; adjusted odds ratio 2.16 (1.01-4.61), P = .047 and higher ACQ score at baseline 2.80 (1.55-5.08), P = .001.

Conclusion

The prevalence of severe asthma in Africa is high and is associated with high morbidity and poor quality of life.

Real-World Effectiveness of Biologics in Patients With Severe Asthma: Analysis of the KoSAR

PURPOSE

Severe asthma is associated with high morbidity and healthcare utilization; however, treatment options for these patients are limited. This study aimed to determine the therapeutic effects of biologics in clinical practice.

METHODS

This multicenter, retrospective cohort study included 136 patients who received biologics for at least 4 months between September 2017 and July 2022 at 25 medical centers affiliated with the Korean Severe Asthma Registry (KoSAR). The study evaluated the treatment effects, including acute exacerbation rates, maintenance of oral corticosteroid dosages, lung function, quality of life, blood eosinophil count, and fractional exhaled nitric oxide (FeNO) levels, by comparing measurements before and after 4 months of biologic treatment. Responses for each medication was evaluated based on the Global Evaluation of Treatment Effectiveness score, and any adverse reactions were summarized.

RESULTS

With the administration of biologics over the course of 4 months, there was a reduction in asthma acute exacerbations, a significant improvement in lung function, and a significant decrease in daily maintenance dose of oral steroid. Blood eosinophil counts decreased in the mepolizumab and reslizumab groups, while FeNO levels decreased only in the dupilumab group. The Asthma Control Test, Quality of Life Questionnaire for Adult Korean Asthmatics, and the EuroQol-visual analogue scale scores showed a significant improvement. Most patients (80.15%) responded to the biologic treatment. Meanwhile, non-responders often had chronic rhinosinusitis as a comorbidity, exhibited lower lung function, and required higher doses of oral steroids. No severe adverse events were reported.

CONCLUSIONS

Biologics are highly effective in Korean patients with Type 2 severe asthma, significantly reducing acute exacerbation rates and doses of oral corticosteroids, while also improving lung function. Therefore, it seems beneficial to administer biologics without any restrictions to patients exhibiting Type 2 severe asthma.

Managing children's asthma: what role do caregivers' mental representations of trigger and symptom management behaviors play?

OBJECTIVE

Pediatric asthma management is challenging for parents and guardians (hereafter caregivers). We examined (1) how caregivers mentally represent trigger and symptom management strategies, and (2) how those mental representations are associated with actual management behavior.

METHODS

In an online survey, N = 431 caregivers of children with asthma rated 20 trigger management behaviors and 20 symptom management behaviors across 15 characteristics, and indicated how often they engaged in each behavior.

RESULTS

Principal components analysis indicated 4 dimensions for trigger management behaviors and 3 for symptom management behaviors. Bayesian mixed-effects models indicated that engagement in trigger management behavior was more likely for behaviors rated as affirming caregiver activities. However, trigger management behavior did not depend on how highly the behavior was rated as challenging for caregiver, burdensome on child, or routine caregiving. Engagement in symptom management behavior was more likely for behaviors rated as affirming and common and harmless to the child, but was unrelated to how highly a behavior was rated as challenging for caregivers.

CONCLUSION

These results suggest that interventions might be particularly useful if they focus on the affirming nature of asthma management behaviors. However, such interventions should acknowledge structural factors (e.g. poverty) that constrain caregivers' ability to act.

Asthma Management Considerations for the Otolaryngologist: Current Therapies

Asthma is frequently comorbid with chronic rhinosinusitis. First-line pharmacologic intervention for asthma includes combination-inhaled corticosteroids with a long-acting-β-agonist, preferably formoterol. Although short-acting-β-agonists have historically been used as sole rescue option, studies show that this approach can lead to more asthma-related exacerbations and greater mortality. Similarly, oral corticosteroids should be used sparingly due to their significant adverse effect profile. Nonpharmacological interventions for asthma include counseling on modifiable risk factors, such as smoking, physical activity, occupational exposures, and healthy diets. Management of patients with unified airway disease should incorporate a multidisciplinary team consisting of otolaryngologists and asthma specialists.

Is the assessment of asthma treatment efficacy sufficiently comprehensive?

The goal of asthma guideline therapy is to achieve disease control, by minimizing impairment and decreasing the risk of exacerbations and adverse effects of the disease and its treatment. The primary objective of most clinical trials of biologics for severe asthma is a reduction in exacerbation rate. Recently, studies with patients at the lower guideline steps have also selected exacerbation reduction as a primary objective. These trials in patients with milder disease frequently demonstrate statistically significantly fewer exacerbations, but their power calculations reflect larger sample size and smaller effect size. Exacerbations have a precise consensus definition, although a minimal clinically important difference has not been established. Reduction of exacerbations in severe asthma is commonly 10-fold greater than in mild disease. Further, reduction in exacerbations is not always associated with reduced impairment. If superior control is the objective, both domains should demonstrate consistent and parallel improvement. The disconnect may reflect the need for alternative tools for measurement of impairment or, possibly, different therapeutic mechanisms of action. Determining response to biologics or discussion of disease remission requires assessing symptoms that may occur daily rather than focusing on exacerbations that occur once or twice a year for patients at the highest steps of care according to the guidelines.

The efficacy of citalopram or escitalopram in patients with asthma and major depressive disorder

BACKGROUND

Major depressive disorder is common in people with asthma. Yet, few studies have evaluated depression treatment in those with asthma.

OBJECTIVE

To explore the relationship between antidepressant use, depressive symptoms, and asthma control, pooled data from 3 randomized trials of either citalopram or escitalopram were assessed.

METHODS

Linear fixed effects and binary logistic regression analyses were conducted with between-subject covariates including treatment group, (original) study, and demographics. The within-subject effect of visit, and a treatment group-visit (between-within) interaction effect, were also evaluated. Analyses were repeated in a high asthma exacerbation subgroup having at least 3 oral corticosteroid bursts in the previous 12 months. Outcomes included the Hamilton rating scale for depression (HAM-D17), the 7-item asthma control questionnaire (ACQ), and oral corticosteroid use (yes or no).

RESULTS

In the pooled sample (n = 255), the antidepressant treatment group exhibited lower HAM-D17 overall (P ≤ .001) and a lower likelihood for oral corticosteroid use (P ≤ .001) relative to the placebo group. In the high-exacerbation subgroup (n = 96), treatment group participants had lower overall asthma control questionnaire (P = .004) and HAM-D17 scores (P ≤ .001), and a lower likelihood of oral corticosteroid use (P = .003), relative to placebo participants. All treatment group interaction effects were not significant.

CONCLUSION

Citalopram or escitalopram exhibited efficacy in reducing depressive symptoms and the need for rescue oral corticosteroids in patients with asthma and major depressive disorder. Future work should determine whether selective serotonin reuptake inhibitors are effective at improving asthma outcomes in those with asthma who are not depressed.

TRIAL REGISTRATION

Clinicaltrials.gov Identifier: NCT00621946 and NCT01324700 (one study was conducted before ClinicalTrials.gov requirements).

Asthma exacerbations and eosinophilia in the UK Biobank: a genome-wide association study

Background

Asthma exacerbations reflect disease severity, affect morbidity and mortality, and may lead to declining lung function. Inflammatory endotypes (e.g. T2-high (eosinophilic)) may play a key role in asthma exacerbations. We aimed to assess whether genetic susceptibility underlies asthma exacerbation risk and additionally tested for an interaction between genetic variants and eosinophilia on exacerbation risk.

Methods

UK Biobank data were used to perform a genome-wide association study of individuals with asthma and at least one exacerbation compared to individuals with asthma and no history of exacerbations. Individuals with asthma were identified using self-reported data, hospitalisation data and general practitioner records. Exacerbations were identified as either asthma-related hospitalisation, general practitioner record of asthma exacerbation or an oral corticosteroid burst prescription. A logistic regression model adjusted for age, sex, smoking status and genetic ancestry via principal components was used to assess the association between genetic variants and asthma exacerbations. We sought replication for suggestive associations (p<5×10-6) in the GERA cohort.

Results

In the UK Biobank, we identified 11 604 cases and 37 890 controls. While no variants reached genome-wide significance (p<5×10-8) in the primary analysis, 116 signals were suggestively significant (p<5×10-6). In GERA, two single nucleotide polymorphisms (rs34643691 and rs149721630) replicated (p<0.05), representing signals near the NTRK3 and ABCA13 genes.

Conclusions

Our study has identified reproducible associations with asthma exacerbations in the UK Biobank and GERA cohorts. Confirmation of these findings in different asthma subphenotypes in diverse ancestries and functional investigation will be required to understand their mechanisms of action and potentially inform therapeutic development.

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.

I don't know my child's asthma risk: evidence against satisficing as an explanation for 'don't know' responses

Several studies suggest that "don't know" (DK) responses to risk perception items may represent meaningful expressions of uncertainty about disease risk. However, researchers are often discouraged from including a DK response option in survey items due to concerns about respondents overusing it to minimize cognitive effort-a phenomenon often referred to as satisficing. Our objective was to investigate whether patterns of DK responses to risk perception survey items were consistent with satisficing behavior. We conducted a secondary analysis of survey data from 814 parents and guardians (hereafter caregivers) of children with asthma. Caregivers answered 18 items assessing their perceived risk of their child experiencing two types of poor asthma outcomes: asthma exacerbation, and low asthma control. We examined differences in the frequency and distribution of DK responses across all 18 items and by type of risk perception item (i.e., 2 vs. 5 response options, absolute vs. comparative risk). We found that 32% (n=548) of respondents marked DK at least once. Of the 266 caregivers who provided any DK response, most did so for only 1 or 2 items (51.9%, n=138), and only 6% (n=15) answered DK to more than half of the items. Using random coefficient Poisson models, we found more DK responding for dichotomous absolute (30.1%) than ordinal absolute items (5.3%), b=1.72, p<.001. We also found fewer DK responses to the ordinal absolute items than the comparative items (8.2%), b=-0.49, p<.001. Using Chi-square tests, we found that inattentive responding was not associated with responding DK. Our findings suggest that satisficing is unlikely to completely explain DK responding to perceived risk survey items. Researchers who exclude DK response options from risk perception survey items may obtain an incomplete understanding of their study sample's beliefs about risk.

Linking cognitive and affective heuristic cues to interpersonal risk perceptions and behavior

People often use cognitive and affective heuristics when judging the likelihood of a health outcome and making health decisions. However, little research has examined how heuristics shape risk perceptions and behavior among people who make decisions on behalf of another person. We examined associations between heuristic cues and caregivers' perceptions of their child's asthma risk, the frequency of caregivers' asthma management behaviors, and child health outcomes. We used Ipsos KnowledgePanel to recruit 814 U.S. adult caregivers of children with asthma of the age <18 years. Participants completed a survey at baseline (T1) and 3 months later (T2). Caregivers who, at T1, reported greater negative affect about their child's asthma (affect heuristic cue), greater ease of imagining their child experiencing asthma symptoms (availability heuristic cue), and greater perceived similarity between their child and a child who has ever experienced asthma symptoms (representativeness heuristic cue) reported statistically significantly (p < 0.05) higher interpersonal perceived risk of their child having an exacerbation or uncontrolled asthma at T1. They also indicated at T2 that their child had poorer asthma control and more frequent exacerbations. Greater T1 negative affect was associated with more frequent T2 actions to reduce inflammation, manage triggers, and manage symptoms, and with poorer T2 child health outcomes. Heuristic cues are likely important for interpersonal-not just personal-risk perceptions. However, the interrelationship between caregivers' ratings of heuristic cues (in particular, negative affect) and risk judgments may signify a struggle with managing their child's asthma and need for extra support from health care providers or systems.

Development and Dynamic Responsiveness of the Acute Asthma Exacerbation Survey in Patients With Moderate to Severe Disease

BACKGROUND

The recall periods and response scales of existing surveys of asthma control are poorly suited for studying acute exacerbations.

OBJECTIVE

To develop an instrument able to predict exacerbations after the onset of acute symptoms and with a recall window sufficiently short to study recovery.

METHODS

We developed the six-item Acute Asthma Exacerbation Survey (AAES). Data were collected at baseline, acute, and recovery visits within an established longitudinal protocol for participants with severe asthma. Participants scheduled acute study visits at the first sign of a cold. Nasal lavage samples and lung function measurements were also collected. The AAES data were analyzed using Cronbach α, Spearman correlations, and Kruskal-Wallace methods. We used logistic regression for predictors of bursts of oral corticosteroids (OCS).

RESULTS

Of 130 participants studied at baseline, 52 returned for an acute visit. The AAES scores were elevated at the acute visit and returned to baseline after recovery independently of respiratory virus detection. Cronbach α for the AAES was 0.853, 0.822, and 0.889 at the three respective visits. Compared with participants not needing burst OCS, those with exacerbations had higher acute AAES scores (16 [13.5-18] vs 11.5 [8.2-14], median [interquartile range]; P = .017) and a larger reduction from baseline in lung function. For each 3-point increase in AAES scores, the odds ratio for burst OCS use was 1.64 (95% CI, 1.04-2.57; P = .030).

CONCLUSIONS

The AAES is internally consistent and dynamically responsive during acute asthma exacerbations. Additional validation studies are warranted to support future trials and aid in clinical decision-making.

Evaluation of evidence for interaction between PM2.5 and aeroallergens on childhood asthma exacerbation in Philadelphia, PA, 2011 to 2016

Fine particulate matter (PM2.5) and aeroallergens (i.e., pollen, molds) are known triggers of asthma exacerbation. Despite mechanistic evidence suggesting synergistic effects between PM2.5 and asthma exacerbation, little epidemiologic work has been performed in children, which has exhibited inconsistency. We conducted a time-series study to explore their interactions using electronic health records (EHR) data in Philadelphia, PA, for asthma diagnoses in outpatient, emergency department [ED], and inpatient settings. Daily asthma exacerbation cases (28,540 asthma exacerbation case encounters) were linked to daily ambient PM2.5 and daily aeroallergen levels during the aeroallergen season of a six-year period (mid-March to October 2011-2016). Asthma exacerbation counts were modeled using quasi-Poisson regression, where PM2.5 and aeroallergens were fitted with distributed lag non-linear functions (lagged from 0 to 14-days), respectively, when modeled as the primary exposure variables. Regression models were adjusted for mean daily temperature/relative humidity, long-term and seasonal trends, day-of-week, and major U.S. holidays. Increasing gradient of RR estimates were observed for only a few primary exposure risk factors [PM2.5 (90th vs. 5th percentile)/aeroallergens (90th percentile vs. 0)], across different levels of effect modifiers. For example, RRs for the association between late-season grass pollen (lag1) and asthma exacerbation were higher at higher levels of PM2.5, 5-days preceding the exacerbation event (low PM2.5: RR = 1.01, 95% CI: 0.93-1.09; medium PM2.5: 1.04, 95% CI: 0.96-1.12; high PM2.5: 1.09, 95% CI: 1.01-1.19). However, most of the highest RRs for aeroallergens were instead observed for days with low- or medium- PM2.5 levels; likewise, when PM2.5 was modeled as the primary exposure with aeroallergens as the effect modifier. Most of the RR estimates did not exhibit gradients that suggested synergism, and were of relatively high imprecision. Overall, our study suggested no evidence for interactions between PM2.5 and aeroallergens in their relationships with childhood asthma exacerbation.

Global Initiative for Asthma (GINA) guideline: achieving optimal asthma control in children aged 6-11 years

The Global Initiative for Asthma (GINA) 2021 guidelines for asthma have been set forth with some alterations in step 3, for children from the 6-11-year-old age group. The low-dose inhaled corticosteroid (ICS)-long-acting β-agonist (LABA), very low-dose formoterol-ICS, medium-dose ICS, and ICS-leukotriene receptor antagonist (LTRA) combination were recommended in the guideline. We organized this study to draw an effective comparison between these three combinations of controller therapies in the pediatric population. A retrospective study was conducted at the Aga Khan University Hospital (Karachi, Pakistan), which enrolled 114 children aged 6-11 years old from July 2021 to December 2022. These children were admitted with asthma exacerbations and were discharged on controller medications as per GINA guidelines on step 3 for control of asthma for 3 months. They were then followed for re-admission within 30 days of discharge, number of emergency room (ER) visits with asthma exacerbations for 1 year, number of admissions with asthma, including high dependency unit and pediatric intensive care unit (PICU) admissions, and length of stay per admission for all admissions in the subsequent year. The pulmonary function test was done at the 1-week follow-up in the clinic after discharge and at the 3-month visit post-discharge. A total of 114 pediatric patients from 6 to 11 years old were enrolled in the study period, out of which 36 (31.57%), 33 (28.9%), and 34 (29.82%) patients were categorized into ICS-LABA, ICS, and ICS-LTRA groups, respectively. ER visits were significantly low in the ICS-LABA group, followed by the ICS-LRTA group and then the ICS group (1.75±0.96 versus 2.93±1.412 versus 3.11±1.21, p<0.001). Similar statistically significant results were observed on the average number of admissions per year (1.52±1.02 versus 1.96±0.84 versus 2.06±1.07, p=0.047) and the number of patients needing PICU (13.88% versus 26.47% versus 39.39%, p=0.034) in these groups, respectively. ICS-LABA group patients had the best values of the forced expiratory volume in one second (FEV1) and FEV1/forced vital capacity ratio after pulmonary function tests at 3 months follow-up, followed by ICS-LTRA and ICS group. Amongst the three options for regimens for children managed at step 3 on GINA 2021 guidelines, ICS-LABA therapy helps attain optimal patient outcomes and lung functions in children with asthma, followed by ICS-LTRA and ICS group, respectively.

Histamine-releasing factor in severe asthma and rhinovirus-associated asthma exacerbation

BACKGROUND

Histamine-releasing factor (HRF) is implicated in allergic diseases. We previously showed its pathogenic role in murine models of asthma.

OBJECTIVE

We aim to present data analysis from 3 separate human samples (sera samples from asthmatic patients, nasal washings from rhinovirus [RV]-infected individuals, and sera samples from patients with RV-induced asthma exacerbation) and 1 mouse sample to investigate correlates of HRF function in asthma and virus-induced asthma exacerbations.

METHODS

Total IgE and HRF-reactive IgE/IgG as well as HRF in sera from patients with mild/moderate asthma or severe asthma (SA) and healthy controls (HCs) were quantified by ELISA. HRF secretion in culture media from RV-infected adenovirus-12 SV40 hybrid virus transformed human bronchial epithelial cells and in nasal washings from experimentally RV-infected subjects was analyzed by Western blotting. HRF-reactive IgE/IgG levels in longitudinal serum samples from patients with asthma exacerbations were also quantified.

RESULTS

HRF-reactive IgE and total IgE levels were higher in patients with SA than in HCs, whereas HRF-reactive IgG (and IgG1) level was lower in asthmatic patients versus HCs. In comparison with HRF-reactive IgElow asthmatic patients, HRF-reactive IgEhigh asthmatic patients had a tendency to release more tryptase and prostaglandin D2 on anti-IgE stimulation of bronchoalveolar lavage cells. RV infection induced HRF secretion from adenovirus-12 SV40 hybrid virus transformed bronchial epithelial cells, and intranasal RV infection of human subjects induced increased HRF secretion in nasal washes. Asthmatic patients had higher levels of HRF-reactive IgE at the time of asthma exacerbations associated with RV infection, compared with those after the resolution. This phenomenon was not seen in asthma exacerbations without viral infections.

CONCLUSIONS

HRF-reactive IgE is higher in patients with SA. RV infection induces HRF secretion from respiratory epithelial cells both in vitro and in vivo. These results suggest the role of HRF in asthma severity and RV-induced asthma exacerbation.

Serum autophagy protein 5 is positively related to T helper 2/T helper 1 ratio, inflammation, and exacerbation in adult asthma patients

BACKGROUND

Autophagy protein 5 (ATG5) regulates airway epithelial cell autophagy, immune response, and inflammation, which is involved in asthma progression. This study aimed to evaluate ATG5 levels and its clinical roles in adult asthma patients.

METHODS

Totally, 200 adult asthma patients and 100 healthy controls (HCs) were enrolled in this case-control study. Subsequently, serum ATG5 was measured by enzyme-linked immunosorbent assay.

RESULTS

ATG5 was increased in asthma patients compared with HCs [median (interquartile range): 44.2 (31.7-77.8) vs. 23.2 (16.7-39.2) ng/mL] (P < 0.001). In asthma patients, ATG5 was positively related to male gender (P = 0.022), a family history of asthma (P = 0.035), eosinophil count (P < 0.001), and immune globulin E (P < 0.001), while it was negatively correlated with forced expiratory volume in 1 s (FEV1)/forced vital capacity (P < 0.001) and FEV1 (Predicted) (P < 0.001). Meanwhile, ATG5 was inversely associated with T helper (Th) 1 cells (P = 0.008), while it was positively linked with Th2 cells (P < 0.001), Th2/Th1 ratio (P < 0.001), interleukin (IL)-4 (P = 0.002), and IL-4/interferon-γ ratio (P = 0.015). Additionally, ATG5 was positively correlated with tumor necrosis factor-α (P < 0.001), IL-1β (P = 0.001), IL-6 (P = 0.003), and IL-17 (P = 0.029). Notably, ATG5 was elevated in asthma patients at exacerbation compared to those at remission [median (interquartile range): 53.6 (37.6-90.0) vs. 35.6 (28.2-51.5) ng/mL] (P < 0.001). It was also noteworthy that ATG5 was positively linked with exacerbation severity in asthma patients (P = 0.005).

CONCLUSION

Serum ATG5 is related to increased Th2/Th1 ratio, inflammation, exacerbation risk and severity in adult asthma patients, which serves as a candidate marker for the management of asthma. However, further validation is still needed.

How are mental representations of asthma triggers and symptoms related to interpersonal risk perceptions? A psychometric investigation of caregivers of children with asthma

OBJECTIVE

Parents and guardians (hereafter caregivers) make decisions for their children's medical care. However, many caregivers of children with asthma struggle to understand their child's illness. We used the psychometric paradigm to investigate how caregivers conceptualize, or mentally represent, asthma triggers and symptoms and how these representations are linked to perceived asthma exacerbation risk.

METHODS

We asked 377 caregivers of children with asthma across the U.S. to rate 20 triggers or 20 symptoms along 15 characteristics. Caregivers also indicated their perceived risk of their child having an asthma exacerbation (hereafter interpersonal risk perceptions). Using principal components analysis, we extracted key dimensions underlying caregivers' ratings on the characteristics. Then we related the triggers' and symptoms' scores on the dimensions to caregivers' interpersonal risk perceptions.

RESULTS

Interpersonal risk perceptions were higher for triggers with high ratings for the dimensions severe and relevant, and negative affect-yet manageable, but not chronic-yet unpredictable. Risk perceptions were also higher for symptoms with high ratings for the dimensions severe and unpredictable, and relevant and common, but not self-blame or manageable despite unknown cause.

CONCLUSION

By identifying key dimensions underlying caregivers' mental representations of asthma triggers and symptoms, these findings can inform a new approach to asthma education.

Exploring Caregiver Interest in and Preferences for Interventions for Children With Risk of Asthma Exacerbation: Web-Based Survey

BACKGROUND

Maintaining control of asthma symptoms is the cornerstone of asthma treatment guidelines in the United States. However, suboptimal asthma control and asthma exacerbations among young people are common and are associated with many negative outcomes. Interventions to improve asthma control are needed. For such interventions to be successful, it is necessary to understand the types of interventions that are appealing to caregivers of children with different levels of risk of exacerbation.

OBJECTIVE

This study aimed to evaluate whether caregivers of children with high (vs low) risk of asthma exacerbation show different levels of interest in and preferences for potential intervention programs and delivery methods.

METHODS

We contracted with Ipsos to administer a web-based survey to caregivers of children with asthma who were residing in the United States. Caregivers (N=394) reported their interest (1=not at all; 3=a lot) in 9 possible intervention programs and 8 possible intervention delivery methods. Caregivers also indicated their preferences by selecting the 3 intervention programs and 3 delivery methods that "most" interested them. Finally, caregivers completed 2 open-ended questions asking what other resources might be useful for managing their children's asthma. We classified children as having a high risk of exacerbation if they had an exacerbation in the past 3 months (n=116) and a low risk of exacerbation if otherwise (n=278).

RESULTS

Caregivers reported higher levels of interest in all intervention programs and delivery methods if they cared for a child with a high risk rather than a low risk of exacerbation. However, regardless of the child's risk status, caregivers expressed the highest levels of interest in programs to increase their child's self-management skills, to help pay for asthma care, and to work with the school to manage asthma. Caregivers expressed the highest levels of interest in delivery methods that maintained personal control over accessing information (websites, videos, printed materials, and smartphone apps). Caregivers' preferences were consistent with their interests; programs and delivery methods that were rated as high in interest were also selected as one of the 3 that "most" interested them. Although most caregivers did not provide additional suggestions for the open-ended questions, a few caregivers suggested intervention programs and delivery methods that we had not included (eg, education about avoiding triggers and medication reminders).

CONCLUSIONS

Similar interests and preferences among caregivers of children with high and low risk of exacerbation suggest a broad need for support in managing childhood asthma. Providers could help caregivers by directing them toward resources that make asthma care more affordable and by helping their children with asthma self-management. Interventions that accommodate caregivers' concerns about having personal control over access to asthma information are likely to be more successful than interventions that do not.

Metabolomics identifies disturbances in arginine, phenylalanine, and glycine metabolism as differentiating features of exacerbating atopic asthma in children

Background

Asthma exacerbations are highly prevalent in children, but only a few studies have examined the biologic mechanisms underlying exacerbations in this population.

Objective

High-resolution metabolomics analyses were performed to understand the differences in metabolites in children with exacerbating asthma who were hospitalized in a pediatric intensive care unit for status asthmaticus. We hypothesized that compared with a similar population of stable outpatients with asthma, children with exacerbating asthma would have differing metabolite abundance patterns with distinct clustering profiles.

Methods

A total of 98 children aged 6 through 17 years with exacerbating asthma (n = 69) and stable asthma (n = 29) underwent clinical characterization procedures and submitted plasma samples for metabolomic analyses. High-confidence metabolites were retained and utilized for pathway enrichment analyses to identify the most relevant metabolic pathways that discriminated between groups.

Results

In all, 118 and 131 high-confidence metabolites were identified in positive and negative ionization mode, respectively. A total of 103 unique metabolites differed significantly between children with exacerbating asthma and children with stable asthma. In all, 8 significantly enriched pathways that were largely associated with alterations in arginine, phenylalanine, and glycine metabolism were identified. However, other metabolites and pathways of interest were also identified.

Conclusion

Metabolomic analyses identified multiple perturbed metabolites and pathways that discriminated children with exacerbating asthma who were hospitalized for status asthmaticus. These results highlight the complex biology of inflammation in children with exacerbating asthma and argue for additional studies of the metabolic determinants of asthma exacerbations in children because many of the identified metabolites of interest may be amenable to targeted interventions.

Rudin R, Sulca Flores J, Goolkasian G, Sousa J, Rodriguez J, Lipsitz S, Foer D, K. Dalal A. Assessing Equitable Recruitment in a Digital Health Trial for Asthma

OBJECTIVE

This study aimed to assess a multipronged strategy using primarily digital methods to equitably recruit asthma patients into a clinical trial of a digital health intervention.

METHODS

We approached eligible patients using at least one of eight recruitment strategies. We recorded approach dates and the strategy that led to completion of a web-based eligibility questionnaire that was reported during the verbal consent phone call. Study team members conducted monthly sessions using a structured guide to identify recruitment barriers and facilitators. The proportion of participants who reported being recruited by a portal or nonportal strategy was measured as our outcomes. We used Fisher's exact test to compare outcomes by equity variable, and multivariable logistic regression to control for each covariate and adjust effect size estimates. Using grounded theory, we coded and extracted themes regarding recruitment barriers and facilitators.

RESULTS

The majority (84.4%) of patients who met study inclusion criteria were patient portal enrollees. Of 6,366 eligible patients who were approached, 627 completed the eligibility questionnaire and were less frequently Hispanic, less frequently Spanish-speaking, and more frequently patient portal enrollees. Of 445 patients who consented to participate, 241 (54.2%) reported completing the eligibility questionnaire after being contacted by a patient portal message. In adjusted analysis, only race (odds ratio [OR]: 0.46, 95% confidence interval [CI]: 0.28-0.77, p = 0.003) and college education (OR: 0.60, 95% CI: 0.39-0.91, p = 0.016) remained significant. Key recruitment barriers included technology issues (e.g., lack of email access) and facilitators included bilingual study staff, Spanish-language recruitment materials, targeted phone calls, and clinician-initiated "1-click" referrals.

CONCLUSION

A primarily digital strategy to recruit patients into a digital health trial is unlikely to achieve equitable participation, even in a population overrepresented by patient portal enrollees. Nondigital recruitment methods that address racial and educational disparities and less active portal enrollees are necessary to ensure equity in clinical trial enrollment.

Social determinants of health influence preschool and caregiver experiences during symptoms and exacerbations of wheezing

BACKGROUND

Social determinants of health have been inadequately studied in preschool children with wheezing and their caregivers but may influence the care received.

OBJECTIVE

To evaluate the symptom and exacerbation experiences of wheezing preschool children and their caregivers, stratified by risk of social vulnerability, over 1 year of longitudinal follow-up.

METHODS

A total of 79 caregivers and their preschool children with recurrent wheezing and at least 1 exacerbation in the previous year were stratified by a composite measure of social vulnerability into "low" (N = 19), "intermediate" (N = 27), and "high" (N = 33) risk groups. Outcome measures at the follow-up visits included child respiratory symptom scores, asthma control, caregiver-reported outcome measures of mental and social health, exacerbations, and health care utilization. The severity of exacerbations reflected by symptom scores and albuterol use and exacerbation-related caregiver quality of life were also assessed.

RESULTS

Preschool children at high risk of social vulnerability had greater day-to-day symptom severity and more severe symptoms during acute exacerbations. High-risk caregivers were also distinguished by lower general life satisfaction at all visits and lower global and emotional quality of life during acute exacerbations which did not improve with exacerbation resolution. Rates of exacerbation or emergency department visits did not differ, but intermediate- and high-risk families were significantly less likely to seek unscheduled outpatient care.

CONCLUSION

Social determinants of health influence wheezing outcomes in preschool children and their caregivers. These findings argue for routine assessment of social determinants of health during medical encounters and tailored interventions in high-risk families to promote health equity and improve respiratory outcomes.

Incidence rates of childhood asthma with recurrent exacerbations in the US Environmental influences on Child Health Outcomes (ECHO) program

BACKGROUND

Descriptive epidemiological data on incidence rates (IRs) of asthma with recurrent exacerbations (ARE) are sparse.

OBJECTIVES

This study hypothesized that IRs for ARE would vary by time, geography, age, and race and ethnicity, irrespective of parental asthma history.

METHODS

The investigators leveraged data from 17,246 children born after 1990 enrolled in 59 US with 1 Puerto Rican cohort in the Environmental Influences on Child Health Outcomes (ECHO) consortium to estimate IRs for ARE.

RESULTS

The overall crude IR for ARE was 6.07 per 1000 person-years (95% CI: 5.63-6.51) and was highest for children aged 2-4 years, for Hispanic Black and non-Hispanic Black children, and for those with a parental history of asthma. ARE IRs were higher for 2- to 4-year-olds in each race and ethnicity category and for both sexes. Multivariable analysis confirmed higher adjusted ARE IRs (aIRRs) for children born 2000-2009 compared with those born 1990-1999 and 2010-2017, 2-4 versus 10-19 years old (aIRR = 15.36; 95% CI: 12.09-19.52), and for males versus females (aIRR = 1.34; 95% CI 1.16-1.55). Black children (non-Hispanic and Hispanic) had higher rates than non-Hispanic White children (aIRR = 2.51; 95% CI 2.10-2.99; and aIRR = 2.04; 95% CI: 1.22-3.39, respectively). Children born in the Midwest, Northeast and South had higher rates than those born in the West (P < .01 for each comparison). Children with a parental history of asthma had rates nearly 3 times higher than those without such history (aIRR = 2.90; 95% CI: 2.43-3.46).

CONCLUSIONS

Factors associated with time, geography, age, race and ethnicity, sex, and parental history appear to influence the inception of ARE among children and adolescents.

Inhibition of γ-glutamyl transferase suppresses airway hyperresponsiveness and airway inflammation in a mouse model of steroid resistant asthma exacerbation

Introduction

Despite recent advances, there are limited treatments available for acute asthma exacerbations. Here, we investigated the therapeutic potential of GGsTop, a γ-glutamyl transferase inhibitor, on the disease with a murine model of asthma exacerbation.

Methods

GGsTop was administered to mice that received lipopolysaccharide (LPS) and ovalbumin (OVA) challenges. Airway hyperresponsiveness (AHR), lung histology, mucus hypersecretion, and collagen deposition were analyzed to evaluate the hallmark features of asthma exacerbation. The level of proinflammatory cytokines and glutathione were determined with/without GGsTop. The transcription profiles were also examined.

Results

GGsTop attenuates hallmark features of the disease with a murine model of LPS and OVA driven asthma exacerbation. Airway hyperresponsiveness (AHR), mucus hypersecretion, collagen deposition, and expression of inflammatory cytokines were dramatically inhibited by GGsTop treatment. Additionally, GGsTop restored the level of glutathione. Using RNA-sequencing and pathway analysis, we demonstrated that the activation of LPS/NFκB signaling pathway in airway was downregulated by GGsTop. Interestingly, further analysis revealed that GGsTop significantly inhibited not only IFNγ responses but also the expression of glucocorticoid-associated molecules, implicating that GGsTop profoundly attenuates inflammatory pathways.

Conclusions

Our study suggests that GGsTop is a viable treatment for asthma exacerbation by broadly inhibiting the activation of multiple inflammatory pathways.

Comparative effectiveness of omalizumab, mepolizumab, and dupilumab in asthma: A target trial emulation

BACKGROUND

Multiple mAbs are currently approved for the treatment of asthma. However, there is limited evidence on their comparative effectiveness.

OBJECTIVE

Our aim was to compare the effectiveness of omalizumab, mepolizumab, and dupilumab in individuals with moderate-to-severe asthma.

METHODS

We emulated a hypothetical randomized trial using electronic health records from a large US-based academic health care system. Participants aged 18 years or older with baseline IgE levels between 30 and 700 IU/mL and peripheral eosinophil counts of at least 150 cells/μL were eligible for study inclusion. The study period extended from March 2016 to August 2021. Outcomes included the incidence of asthma-related exacerbations and change in baseline FEV1 value over 12 months of follow-up.

RESULTS

In all, 68 individuals receiving dupilumab, 68 receiving omalizumab, and 65 receiving mepolizumab met the inclusion criteria. Over 12 months of follow-up, 31 exacerbations occurred over 68 person years (0.46 exacerbations per person year) in the dupilumab group, 63 over 68 person years (0.93 per person year) in the omalizumab group, and 86 over 65 person years (1.32 per person year) in the mepolizumab group (adjusted incidence rate ratios: dupilumab vs mepolizumab, 0.28 [95% CI = 0.09-0.84]; dupilumab vs omalizumab, 0.36 [95% CI = 0.12-1.09]; and omalizumab vs mepolizumab, 0.78 [95% CI = 0.32-1.91]). The differences in the change in FEV1 comparing patients who received the different biologics were as follows: 0.11 L (95% CI = -0.003 to 0.222 L) for dupilumab versus mepolizumab, 0.082 L (95% CI -0.040 to 0.204 L) for dupilumab versus omalizumab, and 0.026 L (95% CI -0.083 to 0.140 L) for omalizumab versus mepolizumab.

CONCLUSIONS

Among patients with asthma and eosinophil counts of at least 150 cells/μL and IgE levels of 30 to 700 kU/L, dupilumab was associated with greater improvements in exacerbation and FEV1 value than omalizumab and mepolizumab.

Blood Eosinophils for Prediction of Exacerbation in Preschool Children With Recurrent Wheezing

BACKGROUND

Although clinical features of type 2 inflammation have been associated with poorer longitudinal outcomes in preschool children with recurrent wheezing, it remains difficult to predict which children are at highest risk for poor outcomes during a routine clinical encounter.

OBJECTIVE

We tested the hypothesis that prespecified cut points of blood eosinophil counts would predict exacerbation and treatment response outcomes in preschool children with recurrent wheezing and that prediction could be improved with the addition of a second biomarker.

METHODS

Data from 3 clinical trials of 1,074 preschool children aged 12 to 71 months with recurrent wheezing were merged. The primary outcome was the occurrence of any exacerbation during follow-up. Secondary outcomes included the annualized rate of wheezing exacerbations and the occurrence of any exacerbation requiring hospitalization. Exploratory analyses focused on exacerbation outcomes, offline exhaled nitric oxide concentrations, and caregiver-reported asthma control scores after inhaled corticosteroid treatment initiation.

RESULTS

Each blood eosinophil cut point was associated with increased odds of exacerbation, higher exacerbation rates, and greater hospitalization occurrence in preschool children with recurrent wheezing. However, outcome detection was improved in children with more elevated blood eosinophil counts. Addition of a second biomarker of type 2 inflammation improved outcome detection and was further associated with an improved response to initiation of daily inhaled corticosteroids in exploratory analyses. However, the specificity of blood eosinophils was poor.

CONCLUSIONS

Although validation studies are warranted, blood eosinophil cut points may be useful for clinical assessment and future studies of exacerbation and treatment response in preschool children with recurrent wheezing.

Characteristics of Asthma Exacerbations in Emergency Care in Switzerland-Demographics, Treatment, and Burden of Disease in Patients with Asthma Exacerbations Presenting to an Emergency Department in Switzerland (CARE-S)

Emergency care for asthma is provided by general practitioners, pulmonologists, and emergency departments (EDs). Although it is known that patients presenting to EDs with acute asthma exacerbations are a vulnerable population and that this mode of presentation is a risk marker for more severe complications, research on this population is scarce. We conducted a retrospective study on patients with asthma exacerbations who presented to the ED of the University Hospital Basel, Switzerland, during 2017-2020. Of the last 200 presentations, 100 were selected and analyzed to assess demographic information, the use of previous and ED-prescribed asthma medication, and clinical outcomes after a mean period of time of 18 months. Of these 100 asthma patients, 96 were self-presenters, and 43 had the second highest degree of acuity (emergency severity index 2). Global Initiative for Asthma (GINA) step 1 and step 3 were the most common among patients with known GINA levels, accounting for 22 and 18 patients, respectively. A total of 4 patients were undergoing treatment with oral corticosteroids at presentation, and 34 were at discharge. At presentation, 38 patients used the combination therapy of inhaled corticosteroid/long-acting β₂-agonist (ICS/LABA), and 6 patients underwent ICS monotherapy. At discharge, 68 patients were prescribed with ICS/LABA. At entry to the ED, about one-third of patients did not use any asthma medication. In total, 10 patients were hospitalized. None of them needed invasive or non-invasive ventilation. A follow-up for the study was precluded by the majority of patients. This group of asthma patients seemed particularly vulnerable as their asthma medication at presentation was often not according to guidelines or even lacking, and almost all the patients had self-presented to the ED without any reference from a physician. The majority of patients did not give consent to the collection of any follow-up information. These medical shortcomings reflect an urgent medical need to improve care for patients at high risk of asthma exacerbations.

Exacerbation-prone pediatric asthma is associated with arginine, lysine, and methionine pathway alterations

BACKGROUND

The asthma of some children remains poorly controlled, with recurrent exacerbations despite treatment with inhaled corticosteroids. Aside from prior exacerbations, there are currently no reliable predictors of exacerbation-prone asthma in these children and only a limited understanding of the potential underlying mechanisms.

OBJECTIVE

We sought to quantify small molecules in the plasma of children with exacerbation-prone asthma through mass spectrometry-based metabolomics. We hypothesized that the plasma metabolome of these children would differ from that of children with non-exacerbation-prone asthma.

METHODS

Plasma metabolites were extracted from 4 pediatric asthma cohorts (215 total subjects, with 41 having exacerbation-prone asthma) and detected with a mass spectrometer. High-confidence annotations were retained for univariate analysis and were confirmed by a sensitivity analysis in subjects receiving high-dose inhaled corticosteroids. Metabolites that varied by cohort were excluded. MetaboAnalyst software was used to identify pathways of interest. Concentrations were calculated by reference standardization.

RESULTS

We identified 32 unique, cohort-independent metabolites that differed in children with exacerbation-prone asthma compared to children with non-exacerbation-prone asthma. Comparison of metabolite concentrations to literature-reported values for healthy children revealed that most metabolites were decreased in both asthma groups, but more so in exacerbation-prone asthma. Pathway analysis identified arginine, lysine, and methionine pathways as most impacted.

CONCLUSIONS

Several plasma metabolites are perturbed in children with exacerbation-prone asthma and are largely related to arginine, lysine, and methionine pathways. While validation is needed, plasma metabolites may be potential biomarkers for exacerbation-prone asthma in children.

Indoor Aeroallergen Sensitization and Associated Factors in Hospitalized Children with Asthma Exacerbations

Background

Allergic asthma represents the most popular phenotype of childhood asthma and is characterized by eosinophilic airway inflammation associated with specific immunoglobulin E (IgE) antibodies sensitization to various allergens, as evidenced by serology or skin prick test.2 Sensitization to indoor aeroallergens is associated with severe asthma and severe asthma exacerbations.

Objective

This study aimed to identify the prevalence of aeroallergen sensitization and its associated factors in children with an asthma exacerbation in Vietnam.

Methods

A cross-sectional study was conducted at Children's Hospital 1, Ho Chi Minh City (HCMC). Children who were aged 3 to 15 and admitted to the hospital with moderate or severe asthma exacerbation were recruited to the study. Data was collected from interviews and medical records. SPT was used to identify aeroallergen sensitization. The association between school-age, living area, and passive smoking with the odds of aeroallergen sensitization was assessed using a multivariable logistic regression.

Results

The prevalence of aeroallergen sensitization was 82.6% and this figure in school-age children was higher than that in preschool-age ones (93.8% vs 72.1%, p=0.001). School-age, living in HCMC, and passive smoking significantly increased the odds of aeroallergen sensitization in asthmatic children with adjusted OR [95%CI] as 6.9 [2.1-23.3], 4.1 [1.5-11.5], and 2.9 [1.0-8.4], respectively. Asthmatic children with aeroallergen sensitization required more hours to resolve an asthma exacerbation than those without (22.4 vs 15.2, p=0.006).

Conclusion

Aeroallergen sensitization was common in hospitalized children with moderate or severe asthma exacerbation. It is necessary to establish environmental policy and screening practices of aeroallergen sensitization to improve the quality of asthma management for Vietnamese children.

Urinary total conjugated 3-bromotyrosine, asthma severity, and exacerbation risk

Asthma is an inflammatory disease of the airways characterized by eosinophil recruitment, eosinophil peroxidase release, and protein oxidation through bromination, which following tissue remodeling results in excretion of 3-bromotyrosine. Predicting exacerbations and reducing their frequency is critical for the treatment of severe asthma. In this study, we aimed to investigate whether urinary total conjugated bromotyrosine can discriminate asthma severity and predict asthma exacerbations. We collected urine from participants with severe (n = 253) and nonsevere (n = 178) asthma, and the number of adjudicated exacerbations in 1-yr longitudinal follow-up was determined among subjects enrolled in the Severe Asthma Research Program, a large-scale National Institutes of Health (NIH)-funded consortium. Urine glucuronidated bromotyrosine and total conjugated forms were quantified by hydrolysis with either glucuronidase or methanesulfonic acid, respectively, followed by liquid chromatography-tandem mass spectrometry analyses of free 3-bromotyrosine. Blood and sputum eosinophils were also counted. The majority of 3-bromotyrosine in urine was found to exist in conjugated forms, with glucuronidated bromotyrosine representing approximately a third, and free bromotyrosine less than 1% of total conjugated bromotyrosine. Total conjugated bromotyrosine was poorly correlated with blood (r2 = 0.038) or sputum eosinophils (r2 = 0.0069). Compared with participants with nonsevere asthma, participants with severe asthma had significantly higher urinary total conjugated bromotyrosine levels. Urinary total conjugated bromotyrosine was independently associated with asthma severity, correlated with the number of asthma exacerbations, and served as a predictor of asthma exacerbation risk over 1-yr of follow-up.

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.

Analysis of Therapeutic Effect of Elderly Patients with Severe Heart Failure Based on LSTM Neural Model

In recent years, cardiovascular-related diseases have become the "number one killer" threatening human life and health and have received much attention. The timely and accurate detection and diagnosis of arrhythmias and heart failure are relatively common heart diseases, which are of great social value and research significance in improving people's quality of life by providing early treatment or intervention for those who are at risk. Based on this, this paper proposes a deep learning network architecture based on the combination of long- and short-term memory networks and deep residual neural networks for the automatic detection of heart failure. A total of 60 elderly patients with severe heart failure treated in the emergency department of our hospital from August 2019 to August 2021 were selected as the sample subjects of this study. The treatment outcomes and prognostic quality of life of the two groups of patients were compared and analyzed. Based on the unbiased test method, the accuracy of the proposed method on the authoritative open continuous heart rate database PhysioNet was 99.67% (data length 500), 98.84% (data length 1000), and 96.63% (data length 2000). This indicates that the network model can well extract the high-dimensional features of continuous heart rate and improve the accuracy of the classification model. The LSTM neural model proposed in this paper may be able to provide richer information on heart health status for portable ECG detection systems, which have very important clinical value and social significance.

The Correlation of PM2.5 Exposure with Acute Attack and Steroid Sensitivity in Asthma

Bronchial asthma is a common chronic inflammatory disease of the respiratory system. Asthma primarily manifests in reversible airflow limitation and airway inflammation, airway remodeling, and persistent airway hyperresponsiveness. PM2.5, also known as fine particulate matter, is the main component of air pollution and refers to particulate matter with an aerodynamic diameter of ≤2.5 μm. PM2.5 can be suspended in the air for an extensive time and, in addition, can contain or adsorb heavy metals, toxic gases, polycyclic aromatic hydrocarbons, bacterial viruses, and other harmful substances. Epidemiological studies have demonstrated that, in addition to increasing the incidence of asthma, PM2.5 exposure results in a significant increase in the incidence of hospital visits and deaths due to acute asthma attacks. Furthermore, PM2.5 was reported to induce glucocorticoid resistance in asthmatic individuals. Although various countries have implemented strict control measures, due to the wide range of PM2.5 sources, complex components, and unknown pathogenic mechanisms involving the atmosphere, environment, chemistry, and toxicology, PM2.5 damage to human health still cannot be effectively controlled. In this present review, we summarized the current knowledge base regarding the relationship between PM2.5 toxicity and the onset, acute attack prevalence, and steroid sensitivity in asthma.

An asthma collaboration to reduce childhood asthma disparities on the Navajo Nation: Trial protocol for the Community Asthma Program

Navajo children disproportionately experience poor asthma outcomes. Following a one-year community engagement period with key stakeholders from the Navajo Nation, the Community Asthma Program (CAP) was created using evidenced based programs with the goal of reducing asthma disparities among Navajo children. CAP is being evaluated with a six-year, multi-site step-wedge design in three Navajo communities: Tuba City, Chinle and Fort Defiance, Arizona. The primary outcome is asthma exacerbations defined as use of systemic oral corticosteroids, asthma hospitalizations, asthma related ED visits, and ICU admissions. Asthma exacerbations will be measured using data from the electronic medical records of the three community health care centers. Secondary outcomes include will changes in asthma-related events and asthma control. The RE-AIM ( R each and representativeness, 2) E ffectiveness, 3) A doption, 4) I mplementation, and 5) M aintenance) framework is being used to guide the implementation evaluation which includes iterative collection and analysis of process data to identify facilitators and barriers, describe relevant organizational contexts, and inform strategies for dissemination. The CAP intervention requires community engagement and participation, building community capacity, incorporating evidenced-based guidelines and practices while ensuring program strategies actively involve Navajo community members during all steps of the intervention. The outcome of this trial will allow us to determine the effectiveness of a multi-component, community-focused intervention to improve asthma in a tribal community.

Investigational approaches for unmet need in severe asthma

INTRODUCTION

Molecular antibodies (mAb) targeting inflammatory mediators are effective in T2-high asthma. The recent approval of Tezepelumab presents a novel mAb therapeutic option to those with T2-low asthma.

AREAS COVERED

We discuss a number of clinical problems pertinent to severe asthma which are less responsive to current therapies, such as persistent airflow obstruction and airway hyperresponsiveness. We discuss selected investigational approaches, including a number of candidate therapies under investigation in two adaptive platform trials currently in progress, with particular reference to this unmet need, as well as their potential in phenotypes such as neutrophilic asthma and obese asthma, which may or may not overlap with a T2-high phenotype.

EXPERT OPINION

The application of discrete targeting approaches to T2-low molecular phenotypes, including those phenotypes in which inflammation may not arise within the airway, has yielded variable results to date. Endotypes associated with T2-low asthma are likely to be diverse but await validation. Investigational therapeutic approaches must, likewise, be diverse if the goal of remission is to become attainable for all those living with asthma.

Climate Change Related Catastrophic Rainfall Events and Non-Communicable Respiratory Disease: A Systematic Review of the Literature

Climate change is increasing the frequency and intensity of extreme precipitation events, the impacts of which disproportionately impact urban populations. Pluvial flooding and flooding related sewer backups are thought to result in an increase in potentially hazardous human-pathogen encounters. However, the extent and nature of associations between flooding events and non-communicable respiratory diseases such as chronic bronchitis, asthma, and chronic obstructive pulmonary disease (COPD) are not well understood. This research seeks to characterize the state of research on flooding and NCRDs through a systematic review of the scientific literature. We conducted a systematic search of PubMed, Web of Science, and Scopus for published scholarly research papers using the terms flooding, monsoon, and tropical storm with terms for common NCRDs such as asthma, COPD, and chronic bronchitis. Papers were included if they covered research studies on individuals with defined outcomes of flooding events. We excluded review papers, case studies, and opinion pieces. We retrieved 200 articles from PubMed, 268 from Web of Science and 203 from Scopus which comprised 345 unique papers. An initial review of abstracts yielded 38 candidate papers. A full text review of each left 16 papers which were included for the review. All papers except for one found a significant association between a severe weather event and increased risk for at least one of the NCRDs included in this research. Our findings further suggest that extreme weather events may worsen pre-existing respiratory conditions and increase the risk of development of asthma. Future work should focus on more precisely defining measure of health outcomes using validated tools to describe asthma and COPD exacerbations. Research efforts should also work to collect granular data on patients’ health status and family history and assess possible confounding and mediating factors such as neighborhood water mitigation infrastructure, housing conditions, pollen counts, and other environmental variables.

Probiotics in Children with Asthma

A type-2 immune response usually sustains wheezing and asthma in children. In addition, dysbiosis of digestive and respiratory tracts is detectable in patients with wheezing and asthma. Probiotics may rebalance immune response, repair dysbiosis, and mitigate airway inflammation. As a result, probiotics may prevent asthma and wheezing relapse. There is evidence that some probiotic strains may improve asthma outcomes in children. In this context, the PROPAM study provided evidence that two specific strains significantly prevented asthma exacerbations and wheezing episodes. Therefore, oral probiotics could be used as add-on asthma therapy in managing children with asthma, but the choice should be based on documented evidence.