Severe adult-onset asthma: A distinct phenotype

Asthma Inception: Epidemiologic Risk Factors and Natural History Across the Life Course

Asthma is a descriptive label for an obstructive inflammatory disease in the lower airways manifesting with symptoms including breathlessness, cough, difficulty in breathing, and wheezing. From a clinician's point of view, asthma symptoms can commence at any age, although most patients with asthma-regardless of their age of onset-seem to have had some form of airway problems during childhood. Asthma inception and related pathophysiologic processes are therefore very likely to occur early in life, further evidenced by recent lung physiologic and mechanistic research. Herein, we present state-of-the-art updates on the role of genetics and epigenetics, early viral and bacterial infections, immune response, and pathophysiology, as well as lifestyle and environmental exposures, in asthma across the life course. We conclude that early environmental insults in genetically vulnerable individuals inducing abnormal, pre-asthmatic airway responses are key events in asthma inception, and we highlight disease heterogeneity across ages and the potential shortsightedness of treating all patients with asthma using the same treatments. Although there are no interventions that, at present, can modify long-term outcomes, a precision-medicine approach should be implemented to optimize treatment and tailor follow-up for all patients with asthma.

Choosing the Right Biologic for the Right Patient With Severe Asthma

In this instalment of the How I Do It series on severe asthma, we tackle the clinical conundrum of choosing the right biologic for the right patient with severe asthma. With 6 biologics now approved for use in this area comprising 4 different targeting strategies (anti-Ig E: omalizumab; anti-IL-5 and anti-IL-5-receptor: mepolizumab, reslizumab, and benralizumab; anti-IL-4-receptor: dupilumab; anti-thymic stromal lymphopoietin: tezepelumab), this question is increasingly complex. Recognizing that no head-to-head trial has compared biologics, we based our review on the expected effects of inhibiting different aspects of type 2 airway inflammation, supported whenever possible by clinical trial and real-world data. We use 4 variations of a case of severe uncontrolled asthma to develop concepts and considerations introduced in the previous installment ("Workup of Severe Asthma") and discuss pregnancy-related, biomarker-related, comorbidity-related, and corticosteroid dependency-related considerations when choosing a biologic. The related questions of deciding when, why, and how to switch from one biologic to another also are discussed. Overall, we consider that the choice of biologics should be based on the available clinical trial data for the desired efficacy outcomes, the biomarker profile of the patient, safety profiles (eg, when pregnancy is considered), and opportunities to target 2 comorbidities with 1 biologic. Using systemic and airway biomarkers (blood eosinophils and exhaled nitric oxide) and other phenotypic characteristics, we suggest a framework to facilitate therapeutic decision-making. Post hoc studies and new comparative studies are needed urgently to test this framework and to determine whether it allows us to make other clinically useful predictions.

Identification of exhaled volatile organic compounds that characterize asthma phenotypes: A J-VOCSA study

BACKGROUND

Asthma is characterized by phenotypes of different clinical, demographic, and pathological characteristics. Identifying the profile of exhaled volatile organic compounds (VOCs) in asthma phenotypes may facilitate establishing biomarkers and understanding asthma background pathogenesis. This study aimed to identify exhaled VOCs that characterize severe asthma phenotypes among patients with asthma.

METHODS

This was a multicenter cross-sectional study of patients with severe asthma in Japan. Clinical data were obtained from medical records, and questionnaires were collected. Exhaled breath was sampled and subjected to thermal desorption gas chromatography-mass spectrometry (GC/MS).

RESULTS

Using the decision tree established in the previous nationwide asthma cohort study, 245 patients with asthma were divided into five phenotypes and subjected to exhaled VOC analysis with 50 healthy controls (HCs). GC/MS detected 243 VOCs in exhaled breath samples, and 142 frequently detected VOCs (50% of all samples) were used for statistical analyses. Cluster analysis assigning the groups with similar VOC profile patterns showed the highest similarities between phenotypes 3 and 4 (early-onset asthma phenotypes), followed by the similarities between phenotypes 1 and 2 (late-onset asthma phenotypes). Comparisons between phenotypes 1-5 and HC revealed 19 VOCs, in which only methanesulfonic anhydride showed p < 0.05 adjusted by false discovery rate (FDR). Comparison of these phenotypes yielded several VOCs showing different trends (p < 0.05); however, no VOCs showed p < 0.05 adjusted by FDR.

CONCLUSIONS

Exhaled VOC profiles may be useful for distinguishing asthma and asthma phenotypes; however, these findings need to be validated, and their pathological roles should be clarified.

Aeroallergen sensitization patterns among patients with chronic rhinitis with or without concomitant asthma

OBJECTIVES

The aim of this study was to explore the differences in the pattern of allergen sensitization in CR individuals without or with asthma, according to asthma severity.

METHODS

A total of 1066 adults were evaluated. Asthma and chronic⁄allergic rhinits were identified by specialists, questionnaries and skin-prick test. The phenotypic characterization was avaliable from skin-prick test to an aeroallergen extended panel, total IgE and pulmonary function. Using questionnaires and clinical evaluation, participants were classified into the groups: chronic rhinitis alone (CRA) and chronic rhinitis + asthma, the latter subdivided into CR + mild asthma (CRMA) and CR + moderate to severe asthma (CRMSA). Aerollergen sensitization was defined by a positive prick test to one or more allergens associated with nasal symptoms and/or asthma. The association between CR and asthma was evaluated by multivariable logistic regression. The evidence of effect modification of pattern of sensitization in CR on the association with asthma severity and outcomes was examined by introducing interactions terms in the logistic regression models adjusting for confounders.

RESULTS

Frequency of sensitization to aeroallergens was higher in association with asthma in comparison to CRA (CRMA 70.4%; CRMSA 65.0%; CRA 47.0%; p = 0.000). Similarly, the presence of asthma was associated to aeroallergen multiple sensitization (51.5%) (OR = 2.10, 95% CI 1.27-3.50). Additionally, the sensitization to mites, cockroaches, animal epithelium, grasses, and molds, were higher in asthma (56.8%, 24.3%, 12%, 7.13% and 10.3%, respectively). Sensitization to Alternaria alternata, Cladosporium herbarum and dog epithelium was exclusive in asthma groups. A concomitant asthma diagnosis was directly associated with a positive allergen sensitization at least one allergen (62.7%, OR = 2.45, 95% CI 1.80-3.34) and polissensitization (51.5%, OR = 2.10, 95% CI 1.27-3.50).

CONCLUSION

Asthma is associated with multiple allergen sensitization among patients with CR. Some unique profiles of aeroallergen sensitization were observed in patients with CR and asthma. Nevertheless, no difference was found in the sensitization in relation to asthma severity, which suggest atopy is not the main underlying mechanism for asthma severity among patients with CR.

LEVEL OF EVIDENCE

Level 3.

The Neutralization of the Eosinophil Peroxidase Antibody Accelerates Eosinophilic Mucin Decomposition

Eosinophilic airway inflammation, complicated by bronchial asthma and eosinophilic chronic rhinosinusitis (ECRS), is difficult to treat. The disease may become refractory when eosinophilic mucin associated with eosinophil peroxidase (EPX) and autoantibodies fills in the paranasal sinus and small airway. This study investigated the functional role of an anti-EPX antibody in eosinophilic mucin of ECRS in eosinophilic airway inflammation. Eosinophilic mucin was obtained from patients with ECRS. The effects of the anti-EPX antibody on dsDNA release from eosinophils and eosinophilic mucin decomposition were evaluated. Immunofluorescence or enzyme-linked immunosorbent assays were performed to detect the anti-EPX antibody and its supernatant and serum levels in eosinophilic mucin, respectively. The serum levels of the anti-EPX antibody were positively correlated with sinus computed tomography score and fractionated exhaled nitrogen oxide. Patients with refractory ECRS had higher serum levels of the anti-EPX antibody than those without. However, dupilumab treatment decreased the serum levels of the anti-EPX antibody. Immunoglobulins (Igs) in the immunoprecipitate of mucin supernatants enhanced dsDNA release from eosinophils, whereas the neutralization of Igs against EPX stopped dsDNA release. Furthermore, EPX antibody neutralization accelerated mucin decomposition and restored corticosteroid sensitivity. Taken together, the anti-EPX antibody may be involved in the formulation of eosinophilic mucin and be used as a clinical marker and therapeutic target for intractable eosinophilic airway inflammation.

Chronic rhinosinusitis with nasal polyps and allergic rhinitis as different multimorbid treatable traits in asthma

Background

Respiratory multimorbidities are linked to asthma, such as allergic rhinitis (AR) with early allergic asthma and chronic rhinosinusitis (CRS) with nasal polyps (CRSwNP) with late nonallergic asthma.

Objective

Our aim was to investigate the association of asthma severity and control with specific upper airway phenotypes.

Method

Patients with asthma were prospectively recruited from 23 pulmonology and ear, nose, and throat clinics. Asthma severity and control, as well as upper airway comorbidities (AR and non-AR [NAR], CRSwNP, and CRS without nasal polyps [CRSsNP]) were assessed according to international consensus guidelines definitions.

Results

A total of 492 asthmatic patients were included. Half of the asthmatic patients (49.6%) had associated rhinitis (37.0% had AR and 12.6% had NAR) and 36.2% had CRS (16.7% had CRSsNP and 19.5% had CRSwNP), whereas 14.2% had no sinonasal symptoms. Most cases of AR (78%) and NAR (84%) were present in patients with mild-to-moderate asthma, whereas CRSwNP was more frequent in patients with severe asthma (35% [P < .001]), mainly nonatopic asthma (44% [P < .001]). Patients with severe asthma with CRSwNP had worse asthma control, which was correlated (r = 0.249 [P = .034]) with sinus occupancy. Multiple logistic regression analysis showed that late-onset asthma, intolerance of aspirin and/or nonsteroidal anti-inflammatory drugs, and CRSwNP were independently associated with severe asthma.

Conclusion

Severe asthma is associated with CRSwNP, with sinus occupancy affecting asthma control. This study has identified 2 main different upper airway treatable traits, AR and CRSwNP, which need further evaluation to improve management and control of patients with asthma.

Severity of adult-onset asthma - a matter of blood neutrophils and severe obesity

BACKGROUND

Adult-onset asthma is associated with a poor treatment response. The aim was to study associations between clinical characteristics, asthma control and treatment in adult-onset asthma.

METHODS

Previous participants within the population-based Obstructive Lung Disease in Northern Sweden studies (OLIN) were in 2019-2020 invited to clinical examinations including structured interviews, spirometry, fractional exhaled nitric oxide (FeNO), skin prick test and blood sampling. In total, n = 251 individuals with adult-onset asthma (debut >15 years of age) were identified. Uncontrolled asthma was defined according to ERS/ATS and treatment step according to GINA (2019).

RESULTS

Among individuals with uncontrolled asthma (34%), severe obesity (16.3% vs 7.9%, p = 0.041) and elevated levels of blood neutrophils, both regarding mean level of blood neutrophils (4.25*109/L vs 3.67*109/L, p = 0.003), and proportions with ≥4*109/L (49.4% vs 33.3%, p = 0.017) and ≥5*109/L (32.1% vs 13.7%, p < 0.001) were more common than among those with controlled asthma. Adding the dimension of GINA treatment step 1-5, individuals with uncontrolled asthma on step 4-5 treatment had the highest proportions of blood neutrophils ≥5*109/L (45.5%), severe obesity (BMI≥35, 26.1%), dyspnea (mMRC≥2) (34.8%), and most impaired lung function in terms of FEV1%<80% of predicted (42.9%), FEV1

CONCLUSION

This study indicates that in adult-onset asthma, primarily non-type-2 characteristics such as obesity and blood neutrophils associate with poor asthma control and higher doses of inhaled corticosteroids.

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Key Words

• Body mass index
• Eosinophils
• Epidemiology
• Follow-up studies
• Neutrophils
• Sweden

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MESH Headings

• Humans
• Adult
• Neutrophils
• Obesity, Morbid/complications
• Nitric Oxide/therapeutic use
• Asthma/drug therapy
• Eosinophils
• Obesity/complications

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Affiliation(s)

Sofia Winsa-Lindmark Umeå University, Department of Public Health and Clinical Medicine, Section for Sustainable Health/The OLIN Unit, Sweden.
Caroline Stridsman Umeå University, Department of Public Health and Clinical Medicine, The OLIN Unit, Sweden
Axel Sahlin Umeå University, Department of Public Health and Clinical Medicine, Section for Sustainable Health/The OLIN Unit, Sweden
Linnea Hedman Umeå University, Department of Public Health and Clinical Medicine, Section for Sustainable Health/The OLIN Unit, Sweden
Nikolai Stenfors Umeå University, Department of Public Health and Clinical Medicine, The OLIN Unit, Sweden
Tomi Myrberg Umeå University, Department of Surgical and Perioperative Sciences, Anesthesiology and Intensive Care Medicine, Sweden
Anne Lindberg Umeå University, Department of Public Health and Clinical Medicine, The OLIN Unit, Sweden
Eva Rönmark Umeå University, Department of Public Health and Clinical Medicine, Section for Sustainable Health/The OLIN Unit, Sweden
Helena Backman Umeå University, Department of Public Health and Clinical Medicine, Section for Sustainable Health/The OLIN Unit, Sweden

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Phytoestrogen-Based Hormonal Replacement Therapy Could Benefit Women Suffering Late-Onset Asthma

It has been observed that plasmatic concentrations of estrogens, progesterone, or both correlate with symptoms in asthmatic women. Fluctuations in female sex steroid concentrations during menstrual periods are closely related to asthma symptoms, while menopause induces severe physiological changes that might require hormonal replacement therapy (HRT), that could influence asthma symptoms in these women. Late-onset asthma (LOA) has been categorized as a specific asthmatic phenotype that includes menopausal women and novel research regarding therapeutic alternatives that might provide relief to asthmatic women suffering LOA warrants more thorough and comprehensive analysis. Therefore, the present review proposes phytoestrogens as a promising HRT that might provide these females with relief for both their menopause and asthma symptoms. Besides their well-recognized anti-inflammatory and antioxidant capacities, phytoestrogens activate estrogen receptors and promote mild hormone-like responses that benefit postmenopausal women, particularly asthmatics, constituting therefore a very attractive potential therapy largely due to their low toxicity and scarce side effects.

Genomics of Treatable Traits in Asthma

The astounding number of genetic variants revealed in the 15 years of genome-wide association studies of asthma has not kept pace with the goals of translational genomics. Moving asthma diagnosis from a nonspecific umbrella term to specific phenotypes/endotypes and related traits may provide insights into features that may be prevented or alleviated by therapeutical intervention. This review provides an overview of the different asthma endotypes and phenotypes and the genomic findings from asthma studies using patient stratification strategies and asthma-related traits. Asthma genomic research for treatable traits has uncovered novel and previously reported asthma loci, primarily through studies in Europeans. Novel genomic findings for asthma phenotypes and related traits may arise from multi-trait and specific phenotyping strategies in diverse populations.

High Transcriptional Activity and Clinical Correlations in Eosinophils of Patients with Late-Onset Asthma

Background

The immunological features of eosinophils in early-onset asthma (EOA) differ from those in late-onset asthma (LOA). Clinical trials of anti-interleukin-5 (IL-5) treatment for severe eosinophilic asthma showed a better response for LOA patients than EOA patients. We wonder if the transcriptional activity of activated eosinophils was different in EOA and LOA.

Methods

Eosinophils obtained from well-controlled EOA and LOA patients and normal subjects were compared in terms of the mRNA expression of activation-related genes and specific markers related to cell functions in eosinophils activated by IL-5 or IL-17. The correlation between mRNA expression and clinical features and lung function was further analyzed.

Results

The transcriptional expression of most genes was higher in activated eosinophils from LOA patients than in those from EOA patients and normal subjects. After IL-17 stimulation, the expression of certain genes was higher in atopic EOA patients than in non-atopic EOA patients. Similar observation was noted in obese EOA patients. After IL-5 stimulation, the transcriptional expression of most genes in eosinophils from LOA patients was negatively correlated with indicators of lung function. These correlations were less pronounced in EOA patients: After IL-17 stimulation, some genes in EOA patients were negatively correlated with post-bronchodilator changes in lung function.

Conclusion

This study describes differences in the transcriptional active patterns of eosinophils and their correlation to atopy and obesity by age of onset. High transcriptional activity in activated eosinophils and a negative correlation to lung function indicate the importance of eosinophils in the pathogenesis of LOA.

Immunomodulatory Effects of Subacute Inhalation Exposure to Copper Oxide Nanoparticles in House Dust Mite-Induced Asthma

It has been shown that inhalation exposure to copper oxide nanoparticles (CuO NPs) results in pulmonary inflammation. However, immunomodulatory consequences after CuO NP inhalation exposure have been less explored. We tested the effect of CuO NP aerosols on immune responses in healthy, house dust mite (HDM) asthmatic, or allergen immunotherapy (AIT)-treated asthmatic mice (BALB/c, females). The AIT consisted of a vaccine comprising HDM allergens and CpG-loaded nanoparticles (CpG NPs). AIT treatment involved mice being immunized (via subcutaneous (sc) injection; 2 doses) while concomitantly being exposed to CuO NP aerosols (over a 2 week period), starting on the day of the first vaccination. Mice were then sensitized twice by sc injection and subsequently challenged with HDM extract 10 times by intranasal instillation. The asthmatic model followed the same timeline except that no immunizations were administered. All mice were necropsied 24 h after the end of the HDM challenge. CuO NP-exposed healthy mice showed a significant decrease in TH1 and TH2 cells, and an elevation in T-bet+ Treg cells, even 40 days after the last exposure to CuO NPs. Similarly, the CuO NP-exposed HDM asthma model demonstrated decreased TH2 responses and increased T-bet+ Treg cells. Conversely, CuO NP inhalation exposure to AIT-treated asthmatic mice resulted in an increase in TH2 cells. In conclusion, immunomodulatory effects of inhalation exposure to CuO NPs are dependent on immune conditions prior to exposure.

Phenotype overlap in the natural history of asthma

The heterogeneity of asthma makes it challenging to unravel the pathophysiologic mechanisms of the disease. Despite the wealth of research identifying diverse phenotypes, many gaps still remain in our knowledge of the disease's complexity. A crucial aspect is the impact of airborne factors over a lifetime, which often results in a complex overlap of phenotypes associated with type 2 (T2), non-T2 and mixed inflammation. Evidence now shows overlaps between the phenotypes associated with T2, non-T2 and mixed T2/non-T2 inflammation. These interconnections could be induced by different determinants such as recurrent infections, environmental factors, T-helper plasticity and comorbidities, collectively resulting in a complex network of distinct pathways generally considered as mutually exclusive. In this scenario, we need to abandon the concept of asthma as a disease characterised by distinct traits grouped into static segregated categories. It is now evident that there are multiple interplays between the various physiologic, cellular and molecular features of asthma, and the overlap of phenotypes cannot be ignored.

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

BACKGROUND

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

METHODOLOGY

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

RESULT

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

CONCLUSION

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

A real-life comparison of pulmonary and nasal outcomes in patients with severe asthma and nasal polyposis treated with T2-biologics

Background

Severe asthma (SA) with comorbid chronic rhinosinusitis with nasal polyps (CRSwNP) is frequently associated with type 2 (T2) inflammatory endotype. Consequently, therapeutic targets are T2 biologics. The present retrospective study aimed to analyze and compare the clinical efficacy of mepolizumab, benralizumab, omalizumab, and dupilumab in patients with SA and comorbid CRSwNP.

Methods

115 adult patients with SA and CRSwNP receiving 1 of the 4 biologics (mepolizumab n = 31; benralizumab n = 27; dupilumab n = 27; omalizumab n = 30) were included in the retrospective open monocentric study. Pulmonary and rhinological parameters were evaluated by Asthma Control Test (ACT), FEV1%, GINA-severity grade, rhinological questionnaires (CRS VAS-scores and sinonasal QoL RSOM-31) before and after 4-6 months of therapy.

Results

After 4-6 months of therapy, the Asthma Control Test and FEV1% significantly improved in all biologics groups (p < 0.01). GINA-score significantly improved in the omalizumab group only (p < 0.01). Overall, most nasal scores measured by VAS, total and nasal RSOM-31 subscores improved in all treatment groups (p < 0.05). Interestingly, the most significant differences in pre/post scores were observed in the patients receiving dupilumab, with the most notable improvement for all nasal symptoms, RSOM-31 total score, and RSOM-31 nasal subscore. There were no significant changes in the VAS scores loss of smell in the benralizumab group and postnasal drip in the mepolizumab group.

Conclusion

T2-targeting biologics effectively treat asthma in patients with severe asthma and comorbid CRSwNP. However, the efficacy of T2 biologics differs regarding the outcome in CRSwNP.

Diet quality, food intake and incident adult-onset asthma: a Lifelines Cohort Study

PURPOSE

Dietary factors have been suggested as drivers of the rising prevalence of adult-onset asthma, but evidence is inconclusive, possibly due to the complex interrelation with obesity. We aim to explore the relation of diet quality and food intake with incident adult-onset asthma in normal weight and overweight adults of the prospective population-based Lifelines Cohort Study.

METHODS

Incident adult-onset asthma was defined as self-reported asthma at ± 4-year follow-up, in adults free of airway disease at baseline. Diet quality scores and food group intake were assessed at baseline. Log-binomial regression analyses were used to estimate adjusted relative risks (RR) between dietary intake (per portion) and incident adult-onset asthma, in categories of BMI (cutoff: 25 kg/m²).

RESULTS

477 incident asthma cases (75% female, 62% overweight) and 34,698 controls (60% female, 53% overweight) were identified. Diet quality-assessed by the Lifelines Diet Score and Mediterranean Diet Score-was not associated with incident adult-onset asthma in the two BMI groups. Although the dietary intake of several food groups differed between cases and controls, after adjustment for confounders only few remained associated with adult-onset asthma, including red and processed meat (RR: 0.93 per 15 g intake; 95% CI 0.86-0.99) in the normal weight group and intake of cheese (RR 1.09 per 20 g intake; 95% CI 1.00-1.17) and vegetables (RR 1.10 per 50 g intake; 95% CI 1.00-1.21) in the overweight group.

CONCLUSION

The results of this study question the role of food as a 'simple' predictor of adult-onset asthma and call for an integrative approach, including a range of modifiable lifestyle factors and further asthma phenotyping.

Heterogeneity of asthma with nasal polyposis phenotypes: A cluster analysis

BACKGROUND

Chronic rhinosinusitis with nasal polyposis (CRSwNP) affects a significant number of asthmatic patients and is notably associated with a more difficult-to-control asthma and marked inflammation. We need more studies on this specific asthma phenotype and its possible subphenotypes, in order to better individualize treatments.

AIM

The aim of this study is to identify and characterize subphenotypes of asthma patients with CRSwNP using clinical, physiological and inflammatory variables.

METHODS

K-means cluster analysis was performed on 17 clinical, physiological, and inflammatory variables from 1263 patients of all asthma severity and on a subpopulation of patients with asthma and CRSwNP. Study was registered on ClinicalTrials.gov (NCT03694847).

RESULTS

On the overall population, three groups were identified. Cluster T1 (n = 708) are young, have a short asthma duration and a low prevalence of CRSwNP. Cluster T2 (n = 263) have the longest asthma duration and Cluster T3 (n = 292) are older with the shortest asthma duration. Patients in Clusters T2 and T3 have similar prevalences of CRSwNP. On the subpopulation of asthma with CRSwNP, three clusters were also identified. Cluster S1 (n = 83) have mild-to-moderate asthma with normal lung function. Clusters S2 (N = 53) and S3 (N = 42) include patients with severe asthma and decreased lung function, but those in Cluster S2 have a longer asthma duration, whereas those Cluster S3 have late-onset asthma.

CONCLUSIONS

Despite coexistence of asthma and CRSwNP, not all patients have the same evolution of their asthma. Different phenotypes of asthma with CRSwNP can be identified and exploration of the characteristics of these subgroups could lead to a better individualized, targeted management.

The clinical features of asthma exacerbations in early-onset and eosinophilic late-onset asthma may differ significantly

Over 20 years ago, the concept of asthma control was created and appropriate measurement tools were developed and validated. Loss of asthma control can lead to an exacerbation. Years ago, the term "clinically significant asthma exacerbation" was introduced to define when a loss of control is severe enough to declare it an asthma exacerbation. This term is also used by health insurances to determine when an exacerbation is eligible for reimbursement of biologics in clinical practice, however, it sometimes becomes apparent that a clear separation between loss of "asthma control" and an exacerbation is not always possible. In this review, we attempt to justify why exacerbations in early allergic asthma and adult eosinophilic asthma can differ significantly and why this is important in clinical practice as well as when dealing with health insurers.

Down-regulated surfactant protein B in obese asthmatics

BACKGROUND

Obesity is a common comorbid condition in adult asthmatics and known as a feature of asthma severity. However, the molecular mechanism under obesity-induced inflammation has not yet been fully understood.

OBJECTIVE

Considering the essential role of hydrophobic surfactant protein B (SP-B) in lung function, SP-B was targeted to examine its involvement in the development of obesity-induced airway inflammation in asthmatics.

METHODS

The aim was to examine an alteration in circulating SP-B according to obesity in adult asthmatics, 129 asthmatics were enrolled and classified into 3 groups (obese, overweight and normal-weight groups) according to body mass index (BMI). Circulating SP-B levels were determined by enzyme-linked immunosorbent assay. Four single nucleotide polymorphisms of SFTPB gene were genotyped. Serum ceramide levels were measured by liquid chromatography-tandem mass spectrometry.

RESULTS

Significantly lower serum SP-B levels were noted in the obese group than in the overweight or normal-weight group (p = .002). The serum SP-B level was significantly correlated with serum levels of C18:0 ceramide and transforming growth factor beta 1 as well as BMI (r = -0.200; r = -0.215; r = -0.332, p < .050 for all). An inverse correlation was noted between serum SP-B and fractional exhaled nitric oxide levels in female asthmatics (r = -0.287, p = .009). Genetic predisposition of the SFTPB gene at 9306 A>G to the obese and overweight groups was noted.

CONCLUSION

Obesity altered ceramide metabolism leading to pulmonary surfactant dysfunction and impaired resolution of airway inflammation, finally contributing to the phenotypes of obese asthmatics.

Gold Nanoparticles Inhibit Steroid-Insensitive Asthma in Mice Preserving Histone Deacetylase 2 and NRF2 Pathways

Background: Gold nanoparticles (AuNPs) can inhibit pivotal pathological changes in experimental asthma, but their effect on steroid-insensitive asthma is unclear. The current study assessed the effectiveness of nebulized AuNPs in a murine model of glucocorticoid (GC)-resistant asthma. Methods: A/J mice were sensitized and subjected to intranasal instillations of ovalbumin (OVA) once a week for nine weeks. Two weeks after starting allergen stimulations, mice were subjected to Budesonide or AuNP nebulization 1 h before stimuli. Analyses were carried out 24 h after the last provocation. Results: We found that mice challenged with OVA had airway hyperreactivity, eosinophil, and neutrophil infiltrates in the lung, concomitantly with peribronchiolar fibrosis, mucus production, and pro-inflammatory cytokine generation compared to sham-challenged mice. These changes were inhibited in mice treated with AuNPs, but not Budesonide. In the GC-resistant asthmatic mice, oxidative stress was established, marked by a reduction in nuclear factor erythroid 2-related factor 2 (NRF2) levels and catalase activity, accompanied by elevated values of thiobarbituric acid reactive substances (TBARS), phosphoinositide 3-kinases δ (PI3Kδ) expression, as well as a reduction in the nuclear expression of histone deacetylase 2 (HDAC2) in the lung tissue, all of which sensitive to AuNPs but not Budesonide treatment. Conclusion: These findings suggest that AuNPs can improve GC-insensitive asthma by preserving HDAC2 and NRF2.

CCL4 Functions as a Biomarker of Type 2 Airway Inflammation

Eosinophilic airway inflammatory disease is associated with bronchial asthma, with eosinophilic chronic rhinosinusitis (ECRS) typical of refractory type 2 airway inflammation. CCL4 produced at local inflammatory sites is involved in them via the accumulation and activation of type 2 inflammatory cells, including eosinophils. The detailed mechanism of CCL4 production remains unclear, and also the possibility it could function as a biomarker of type 2 airway inflammation remains unresolved. In this study, we evaluated CCL4 mRNA expression and production via the TSLP receptor (TSLPR) and toll-like receptors (TLRs) or proteinase-activated receptor-2 (PAR2) in BEAS-2B bronchial epithelial cells co-incubated with purified eosinophils or eosinophil peroxidase (EPX). We examined serum chemokine (CCL4, CCL11, CCL26, and CCL17) and total IgE serum levels, fractionated exhaled nitrogen oxide (FENO), and CCL4 expression in nasal polyps in patients with severe ECRS and asthma. CCL4 was induced by TSLP under eosinophilic inflammation. Furthermore, CCL4 was released via TLR3 signaling, which was enhanced by TSLP. CCL4 was mainly located in nasal polyp epithelial cells, while serum CCL4 levels were reduced after dupilumab treatment. Serum CCL4 levels were positively correlated with FENO, serum IgE, and CCL17 levels. Thus, CCL4 released from epithelial cells via the innate immune system during type 2 airway inflammation may function as a useful biomarker for the condition.

Switching Treatment from Mepolizumab to Benralizumab for Elderly Patients with Severe Eosinophilic Asthma: A Retrospective Observational Study

Objective Switching from mepolizumab to benralizumab has been reported to significantly improve both asthma control and the lung function. However, the data on its efficacy in elderly patients with severe eosinophilic asthma are limited. This study aimed to assess whether elderly patients with severe eosinophilic asthma could experience an improved asthma control and lung function when switching directly from mepolizumab to benralizumab. Methods In this single-center, retrospective study conducted between February 2017 and September 2018, we assessed the effect of switching the treatment directly from mepolizumab to benralizumab on eosinophil levels, exacerbation rates, and lung function. We compared the treatment responses between the two groups using either Fisher's exact test or Mann-Whitney U-test, as appropriate. Patients We enrolled 12 elderly patients (age ≥65 years) with severe eosinophilic asthma treated with mepolizumab at Hiroshima Prefectural Hospital (Hiroshima, Japan) during the study period. Six patients were switched from mepolizumab to benralizumab, and six continued with the mepolizumab treatment. Results The switch from mepolizumab to benralizumab caused a near-complete reduction in the eosinophil count (p=0.008). The annual rate of clinically relevant exacerbations and hospitalizations diminished as well, albeit with no statistical significance. We found no improvement in the lung function after switching treatment and no difference in the treatment response between the groups. Conclusion Although this study is based on a small sample of participants, the results indicate that both mepolizumab treatment and switching from mepolizumab to benralizumab treatment without a washout period have clinically relevant asthma control benefits for elderly patients with severe eosinophilic asthma.

The emerging roles of eosinophils: Implications for the targeted treatment of eosinophilic-associated inflammatory conditions

Eosinophils have multiple relevant biological functions, including the maintenance of homeostasis, host defense against infectious agents, innate immunity activities, immune regulation through Th1/Th2 balance, anti-inflammatory, and anti-tumorigenic effects. Eosinophils also have a main role in tissue damage through eosinophil-derived cytotoxic mediators that are involved in eosinophilic inflammation, as documented in Th2-high asthma and other eosinophilic-associated inflammatory conditions.

Recent evidence shows that these multiple and apparently conflicting functions may be attributed to the existence of different eosinophil subtypes (i.e.: tissue resident and inducible eosinophils). Therapeutic intervention with biological agents that totally deplete tissues and circulating eosinophils or, vice versa, maintain a minimal proportion of eosinophils, particularly the tissue-resident ones, could therefore have a very different impact on patients, especially when considering the administration of these therapies for prolonged time. In addition, the characterization of the predominant pathway underlying eosinophilic inflammation by surrogate biomarkers (circulating eosinophils, organ-specific eosinophils levels such as eosinophil count in sputum, bronchoalveolar lavage, tissue biopsy; total circulating IgE levels, or the use of FeNO) in the single patient with an eosinophilic-associated inflammatory condition could help in choosing the treatment.

These observations are crucial in light of the increasing therapeutic armamentarium effective in modulating eosinophilic inflammation through the inhibition in different, yet complementary ways of eosinophil pathways, such as the interleukin-5 one (with mepolizumab, benralizumab, reslizumab) or the interleukin-4/13 one (with dupilumab and lebrikizumab), in severe T2-high asthma as well as in other systemic eosinophilic associated diseases, such as eosinophilic granulomatosis with polyangiitis and hypereosinophilic syndrome.

•

Recent evidence pointed out the existence of different eosinophil subtypes, i.e. tissue resident and inducible eosinophils, with different and apparently conflicting functions.

•

Biological therapies with different mechanisms can deplete completely tissues and circulating eosinophils or maintain a minimal proportion of eosinophils, particularly the tissue-resident ones, and this could therefore have a different impact on patients, especially when considering the administration of these therapies for prolonged time.

•

The identification of the predominant pathway underlying eosinophilic inflammation by surrogate biomarkers (circulating eosinophils, organ-specific eosinophils levels such as eosinophil count in sputum, bronchoalveolar lavage, tissue biopsy; total circulating IgE levels, or the use of FeNO) should be sought in the single patient with an eosinophilic-associated inflammatory condition.

•

These considerations may help in choosing the best anti-eosinophilic treatment, considering the increasing therapeutic armamentarium effective in modulating eosinophilic inflammation through the inhibition of the interleukin-5 one (with mepolizumab, benralizumab, reslizumab) or the interleukin-4/13 one (with dupilumab and lebrikizumab)

Asthma Control in Patients with Severe Eosinophilic Asthma Treated with Reslizumab: Spanish Real-Life Data

Background

Reslizumab is an anti-interleukin 5 monoclonal antibody that has demonstrated to reduce the risk of severe exacerbations and to improve symptoms, lung function, and quality of life in randomized controlled trials that included patients with severe eosinophilic uncontrolled asthma (SEUA) and a history of severe exacerbations.

Objective

The aim of the present study was to evaluate the effectiveness of add-on reslizumab in a cohort of patients with SEUA under real-life conditions.

Methods

This was a multi-centre, retrospective, real-life study that included subjects with SEUA treated with reslizumab in 44 asthma units throughout Spain. Eligible patients were those who had received at least one dose of reslizumab as part of normal clinical practice. The primary endpoint was complete asthma control at 52 weeks, defined as absence of severe exacerbations, ACT ≥20 and no maintenance oral corticosteroids (OCS). Demographic, clinical, and functional data were collected at baseline (T0), after four to six months (T1); after 12 months (T2) and beyond 12 months of therapy (T3).

Results

Treatment with reslizumab achieved complete asthma control in 40% of the 208 included SEUA patients and led to a significant reduction in exacerbations (from 3.0; IQR: 2.0–4.0 at V0 to 0.0; IQR: 0.0–0.0 at V2), maintenance OCS use (from 54.8% (95% CI: 48.0–61.6 at T0 to 18.5% (95% CI: 12.5–24.5 at T2) and a meaningful improvement in symptoms in the entire treated population: ACT increased from 12.8 ± 4.5 at V0 to 20.0 ± 5.1 at V2 (p < 0.001). Most of the improvement achieved at 12 months was obtained at 4–6 months. The retention (continuation) rate of reslizumab was 75% through 2 years (95CI%: 1.9–2.1). Overall, reslizumab showed an adequate safety profile.

Conclusion

Reslizumab is an effective therapy for SEUA with adequate safety profile in real-life conditions.

Are serum immunoglobulin concentrations a predictive biomarker of response to anti-IL5/IL5Rα therapies?

BACKGROUND

Approval of biologics has recently revolutionized T2 severe asthma management. However, predictive biomarkers remain highly needed to improve patient's selection.

OBJECTIVE

This study aims to determine whether serum immunoglobulins (Igs) levels might be predictive biomarkers of response to anti-interleukin-5 (IL5)/IL5Rα therapies.

METHODS

Severe asthma patients eligible for mepolizumab or benralizumab were included herein. Serum immunoglobulin quantification was performed at baseline before mepolizumab or benralizumab initiation. After a 6-month treatment of mepolizumab or benralizumab, patients presented a second serum immunoglobulin quantification. The treatment response was evaluated by the GETE (Global Evaluation of Treatment Effectiveness) score at 6 months.

RESULTS

A total of 50 patients were included. Median age was 56 [IQR 48.8-65.3] and 50% were females. Compared to baseline, a significant increase in IgG was observed at 6 months (9.2 [7.8-10.2] g/l vs 10.1 [8.8-11.1] g/l, p = 0.04). The area under the ROC curve was 0.58 [95%IC 0.40-0.77] for blood eosinophil count (p = 0.37), 0.75 [95%IC: 0.58-0.92] for serum IgG concentration (p = 0.009) for predicting the treatment response. According to the Youden index, serum IgG concentration ≥ 9.2 g/l predicts the response to anti-IL5 therapies with a sensitivity of 76.9% and a specificity of 75.7%.

CONCLUSION

Baseline serum IgG concentrations may be a useful tool to predict the response to anti-IL5/IL5Rα therapies but should be confirmed in larger clinical trials. Interestingly, anti-IL5/IL5Rα therapies are associated with a significant increase in serum IgG concentrations at 6 months.

Proximity to Heavy Traffic Roads and Patient Characteristics of Late of Onset Asthma in an Urban Asthma Center

Background: Traffic-related pollution is associated with the onset of asthma and the development of different phenotypes of asthma. Few studies have investigated the association between traffic proximity and late-onset of asthma (LOA) and early-onset asthma (EOA). This study was conducted to investigate the associations of LOA phenotypes with a function of the distance between residence and heavy traffic roads (HTRs).

Methods: The study group consisted of 280 patients who were (LOA: 78.4%) recruited consecutively from a pay-for-performance asthma program to clarify the patient characteristics and proximity to HTRs within 1,000 m from their residences between EOA and LOA in three urban centers in Taiwan. The subsequent analysis focused on patients with LOA (n = 210) linking phenotypes and distance to HTRs.

Results: Subjects with LOA tended to be older than those with EOA and had shorter asthma duration, poorer lung function, lower atopy, and less exposure to fumes or dust at home. Patients with LOA were more likely than those with EOA to live within 900 m of two or more HTRs (14.3 vs. 3.4%, p = 0.02). Among patients with LOA, minimum distance to an HTR was negatively associated with numbers of specific IgE as well as positively associated with the age of onset and body weight significantly. A higher proportion of patients with atopy (26.3 vs. 20.6%, p = 0.001. odds ratio [OR]: 2.82) and anxiety/depression (21.0 vs. 18.1%, p = 0.047. OR: 1.81) and a trend of lower proportion of patients with obese (5.7 vs. 12.4%, p = 0.075) were found to be living within 900 m from HTRs.

Conclusions: Late-onset of asthma (LOA) tended to live in areas of higher HTR density compared to EOAs. Among patients with LOA living close to HTRs, the interaction between traffic-related pollution, allergy sensitization, and mood status were the factors associated with asthma onset early. Obesity may be the factor for later onset who live far from HTRs.

Characterization of T2-Low and T2-High Asthma Phenotypes in Real-Life

Asthma is a heterogeneous and complex condition characterized by chronic airway inflammation, which may be clinically stratified into three main phenotypes: type 2 (T2) low, T2-high allergic, and T2-high non-allergic asthma. This real-world study investigated whether phenotyping patients with asthma using non-invasive parameters could be feasible to characterize the T2-low and T2-high asthma phenotypes in clinical practice. This cross-sectional observational study involved asthmatic outpatients (n = 503) referring to the Severe Asthma Centre of the San Luigi Gonzaga University Hospital. Participants were stratified according to the patterns of T2 inflammation and atopic sensitization. Among outpatients, 98 (19.5%) patients had T2-low asthma, 127 (25.2%) T2-high non-allergic, and 278 (55.3%) had T2-high allergic phenotype. In comparison to T2-low, allergic patients were younger (OR 0.945, p < 0.001) and thinner (OR 0.913, p < 0.001), had lower smoke exposure (OR 0.975, p < 0.001) and RV/TLC% (OR 0.950, p < 0.001), higher prevalence of asthma severity grade 5 (OR 2.236, p < 0.05), more frequent rhinitis (OR 3.491, p < 0.001) and chronic rhinosinusitis with (OR 2.650, p < 0.001) or without (OR 1.919, p < 0.05) nasal polyps, but less common arterial hypertension (OR 0.331, p < 0.001). T2-high non-allergic patients had intermediate characteristics. Non-invasive phenotyping of asthmatic patients is possible in clinical practice. Identifying characteristics in the three main asthma phenotypes could pave the way for further investigations on useful biomarkers for precision medicine.

Severe asthma in Kuwait population: Phenotype-based approach

BACKGROUND

There is increasing recognition of marked phenotypic heterogeneity within severe asthma patients.

METHODS

Severe asthma patients on GINA step 4 or 5 treatment, followed up at Al-Rashed Allergy center Kuwait, were evaluated for: demographics (gender, age, age of asthma onset), comorbidities (allergic rhinitis (AR), chronic rhinosinusitis (CRS), chronic rhinosinusitis with nasal polyposis (CRSwNP), obesity), blood biomarkers (total serum Immunoglobulin E (IgE), peripheral eosinophils), and sensitization to inhalants allergens.

RESULTS

A total of 169 patients were candidates for biological treatment. Patients were divided in two groups based on level of total IgE as a "low" group with IgE<160 IU/ml (n = 55) and "high" group with IgE≥ 160 IU/ml (n = 114). Both groups were further divided in subgroups, "low" and "high", based on absolute number of eosinophils (Eos) in peripheral blood with <300 cells/μl or ≥ 300 cells/μl. Only 10% of patients were in low IgE/low Eos while majority (46%) were in the high IgE/high Eos group. Mean age of patients was 44.1 year with domination of females (n = 123). Majority of patients were obese. AR, CRS and CRSwNP were more common in group with IgE ≥160 IU/ml, while CRS and CRSwNP in group with Eos ≥300 cells/μl.

CONCLUSION

The majority of severe asthma patients in Kuwait are obese females with adult-onset asthma (>18 years of age) who were allergic with comorbid conditions including AR, CRS and CRSwNP, which correlates well with the level of Eos.

The Role of Atopy in COPD and Asthma

Common to several allergic diseases is the generation of immunoglobulin E (IgE) by plasma cells, when exposed to an innocuous antigen. Asthma and chronic obstructive pulmonary disease (COPD) are two prevalent chronic airway inflammatory diseases. Asthma is mediated in some patients through eosinophilic inflammatory mechanisms that include allergic sensitization and Th2-mediated immune airway response. COPD, on the other hand is mainly considered a Th1-mediated inflammatory process with neutrophilic predominance or a non-Th2 inflammation, occasionally associated with the presence of airway bacteria or viruses. IgE production appears to play an important role in the development of both COPD and asthma, as it has been associated to respiratory symptoms, lung function, bacterial and viral infections, airway remodeling and bronchial hyperreactivity in both diseases. The aim of this review is to summarize all current data concerning the role of specific and total IgE in COPD and asthma and to highlight similarities and differences in view of possible therapeutic interventions.

Determinants of blood eosinophilia in moderate and severe asthmatic patients during childhood: Evidence from the severe asthma molecular phenotype (SAMP) cohort

BACKGROUND

Asthma is a heterogeneous disease in which the interaction between genetic and environmental factors plays a major role. The significance of blood eosinophil is unclear. The aim of the study was to determine the significance of blood eosinophil count in moderate-to-severe asthmatic children of preschool age and school age.

METHODS

This was a prospective cross-sectional study performed from 2011 to 2015 including children from the severe asthma molecular phenotype (SAMP) cohort at Trousseau Hospital (Paris, France). We included children with severe and moderate asthma, or severe and moderate recurrent wheeze, aged from 1 to 15 years at the time of exploration.

RESULTS

We analyzed data from 402 children: 248 of preschool age and 154 of school age. Blood eosinophil count third quartile thresholds were 322 and 600 cells/μL for the preschool- and school-age groups, respectively. In multivariate analysis, a blood eosinophil count over this threshold was associated with elevated total IgE (OR = 5.33, P < .01), multiple hospitalizations for asthma attacks (OR = 4.96, P = .03), and a maternal history of asthma (OR = 4.91, P = .01) in preschool children; and with staphylococcal toxin-specific IgE (OR = 2.75, P = .03) in children of school age. Random forest analysis reinforced these results.

CONCLUSION

High blood eosinophil count is linked to both atopic features and control of asthma with different parameters associated with these features depending on age.

Risk factors for severe adult-onset asthma: a multi-factor approach

BACKGROUND

The aim was to identify risk factors for severe adult-onset asthma.

METHODS

We used data from a population-based sample (Adult Asthma in Finland) of 1350 patients with adult-onset asthma (age range 31-93 years) from Finnish national registers. Severe asthma was defined as self-reported severe asthma and asthma symptoms causing much harm and regular impairment and ≥ 1 oral corticosteroid course/year or regular oral corticosteroids or waking up in the night due to asthma symptoms/wheezing ≥ a few times/month. Sixteen covariates covering several domains (personal characteristics, education, lifestyle, early-life factors, asthma characteristics and multiple morbidities) were selected based on the literature and were studied in association with severe asthma using logistic regressions.

RESULTS

The study population included 100 (7.4%) individuals with severe asthma. In a univariate analysis, severe asthma was associated with male sex, age, a low education level, no professional training, ever smoking, ≥ 2 siblings, ≥ 1 chronic comorbidity and non-steroidal anti-inflammatory drug (NSAID)-exacerbated respiratory disease (NERD) (p < 0.05), and trends for association (p < 0.2) were observed for severe childhood infection, the presence of chronic rhinosinusitis with nasal polyps, and being the 1st child. The 10 variables (being a 1st child was removed due to multicollinearity) were thus entered in a multivariate regression model, and severe asthma was significantly associated with male sex (OR [95% CI] = 1.96 [1.16-3.30]), ever smoking (1.98 [1.11-3.52]), chronic comorbidities (2.68 [1.35-5.31]), NERD (3.29 [1.75-6.19]), and ≥ 2 siblings (2.51 [1.17-5.41]). There was a dose-response effect of the total sum of these five factors on severe asthma (OR [95% CI] = 2.30 [1.81-2.93] for each one-unit increase in the score).

CONCLUSIONS

Male sex, smoking, NERD, comorbidities, and ≥ 2 siblings were independent risk factors for self-reported severe asthma. The effects of these factors seem to be cumulative; each additional risk factor gradually increases the risk of severe asthma.

Dual biologic therapy in a patient with severe asthma and other allergic disorders

Severe asthma is very difficult to manage in many individuals, and systemic corticosteroids are often used to prevent or manage acute exacerbations. Furthermore, comorbid allergic conditions may render standard therapies inadequate. A 51-year-old man presented with severe eosinophilic asthma requiring nearly constant oral corticosteroid usage despite using high-dose inhaled corticosteroids and secondary asthma controllers. His condition was complicated by aspirin-exacerbated respiratory disease, including severe nasal polyposis, chronic rhinosinusitis, as well as chronic idiopathic urticaria. Mepolizumab was initiated and led to dramatic improvement of asthma over 6 months. However, he continued to experience exacerbations of chronic idiopathic urticaria not responsive to H1-antihistamines. Omalizumab was added, and the patient's urticaria attained marked improvement with only an occasional breakthrough rash. Dual biologic therapies can be a unique and useful steroid-sparing treatment option for patients with uncontrolled severe asthma and chronic idiopathic urticaria.

Asthma Across the Ages: Adults

Asthma is a common disease affecting approximately 300 million people worldwide, across all age ranges. Despite advances in asthma outcomes of the last few decades, there remains room for improvement in asthma management and for patient outcomes, particularly in older patients. The heterogeneity of asthma is now well recognized, and is known to complicate response to treatment and patient behavior and impact health outcomes. Asthma and its heterogeneity change according to age. Asthma affects people differently across the life span. In adults, prevalence is highest among those in middle age; however, mortality is greater in the older age group. In this clinical commentary, we describe how age impacts asthma prevalence and incidence, outcomes, disease expression, and approach to management in adulthood and in older patients.

Dupilumab improves upper and lower airway disease control in chronic rhinosinusitis with nasal polyps and asthma

BACKGROUND

Chronic rhinosinusitis with nasal polyps (CRSwNP) and type 2 asthma share the same inflammatory pathophysiology and are frequent comorbidities. Dupilumab, a fully human monoclonal antibody, blocks the shared receptor component for interleukin 4 and interleukin 13, which are key and central drivers of type 2 inflammation.

OBJECTIVE

We report the effect of dupilumab vs placebo on outcome measures of the upper and lower airways and health-related quality of life (HRQoL) in the pooled population of patients with CRSwNP and comorbid asthma from the phase 3 SINUS-24 (NCT02912468) and SINUS-52 (NCT02898454) studies.

METHODS

In these randomized, double-blind, placebo-controlled trials, patients received subcutaneous dupilumab 300 mg (n = 438) or placebo (n = 286) every 2 weeks on a background of mometasone furoate nasal spray. Changes from baseline at week 24 in the upper and lower airway outcome measures are reported.

RESULTS

Of the 724 patients randomized, 428 (59.1%) had comorbid asthma. In patients with asthma at week 24, dupilumab vs placebo improved the nasal polyp score (-2.04), patient-reported nasal congestion score (-1.04), Lund-Mackay computed tomography scan score (-6.43), peak nasal inspiratory flow (46.15 L/min), and 22-item sinonasal outcome test score (-21.42; all P < .001). The forced expiratory volume in 1 second and 6-item asthma control questionnaire scores were also markedly improved with dupilumab vs placebo. The most common adverse events (nasopharyngitis, headache, injection-site erythema, worsening of nasal polyposis, and asthma) were more frequent with placebo than dupilumab.

CONCLUSION

Dupilumab improved upper and lower airway outcome measures and HRQoL in patients with severe CRSwNP and comorbid asthma and was well tolerated.

TRIAL REGISTRATION

ClinicalTrials.gov Identifiers: NCT02912468 (SINUS-24) and NCT02898454 (SINUS-52).

Molecular analysis of phenotypic interactions of asthma

INTRODUCTION

Asthma is a heterogeneous disease characterized by multiples respiratory symptoms; this is a polygenic entity that involves a complex interaction of environmental factors and inherent to the individual. To understand the development of asthma, some phenotypes have been proposed.

OBJECTIVE

This work's purpose was to explore different molecules related to asthma development and to define each phenotype's specific characteristics.

MATERIAL AND METHODS

96 adult patients diagnosed with asthma before any treatment were enrolled in the protocol. Spirometric parameters, circulating leukocytes, serum IgE, body mass index, exhaled nitric oxide (FENO), and leukotrienes (LTB4) in urine were determined in each patient. The presence of asthma phenotypes proposed by the Global Initiative for Asthma (GINA) were explored: A) Allergic asthma, B) Non-allergic asthma, C) Late-onset asthma, D) Asthma with persistent airflow limitation, and E) Asthma with overweight and obesity.

RESULTS

In the cohort analyzed, we found four of phenotypes proposed by GINA; however, these phenotypes overlapped, due to this, 4 groups were integrated with allergic, non-allergic and obese patients, which were the main phenotypes. The main overlap was that of patients not-obese allergic, and was characterized by earlier onset, elevated levels of IgE, LTB4 and inflammasome related cytokines. Non-allergic patients had a significant association between interleukin (IL)-18 and IL-18 binding protein (BP) with narrow ratio between these cytokines. Finally, LTB4 had remarkable capacity to discriminate between allergic and not allergic patients.

CONCLUSIONS

Asthmatic phenotypes exist as interrelated characteristics and not as discrete entities. High levels of leukotrienes and IgE are hallmarks in the allergic phenotype of asthma.

Nasal polyp eosinophilia and FeNO may predict asthma symptoms development after endoscopic sinus surgery in CRS patients without asthma

BACKGROUND

Asthma is a significant comorbidity of eosinophilic chronic rhinosinusitis (CRS). Type2-driven biomarkers such as sinus tissue eosinophilia and fractional nitric oxide (FeNO) may be utilized to detect high risk patients who develop asthma symptoms after endoscopic sinus surgery (ESS) in CRS patients.

METHODS

Thirty-six CRS patients without asthma who agreed to undergo ESS between October 2015 and December 2017 were prospectively observed for 12 months following ESS. They were monitored for the development of typical asthma symptoms including dyspnea, wheezes, and cough which responded to anti-asthma medication. Biomarkers were compared between patients who developed asthma symptoms after ESS (asthma symptoms group) and those who did not (non-asthma group). Biomarker changes following ESS intervention were also evaluated.

RESULTS

Six patients were lost to follow after ESS. Thus, 30 CRS patients [16 with nasal polyps (NPs) proved by surgery] were followed. Seven (23%) newly complained of asthma symptoms during follow-up. Levels of FeNO and the prevalence of eosinophilic NPs (eosinophils ≥ 70/high power fields) were significantly higher in the asthma symptom group than in non-asthma group [50.7 ppb vs 22.4 ppb for FeNO levels, and 100% (n = 3) vs 23% (n = 3) for eosinophilic NP prevalence, both p < 0.05]. Levels of sputum periostin decreased significantly by ESS in the non-asthma group. However, changes of biomarkers after ESS were comparable between the two groups.

CONCLUSIONS

Eosinophils in NPs (≥70/high power fields) and preoperative FeNO may be significant biomarkers for predicting the development of asthma symptoms after ESS.

The Nose as a Route for Therapy: Part 1. Pharmacotherapy

This article reviews nasal structure and function in the light of intranasal pharmacotherapy. The nose provides an accessible, fast route for local treatment of nose and sinus diseases, with lower doses than are necessary systemically and few adverse effects. It can also be used for other medications as it has sufficient surface area protected from local damage by mucociliary clearance, absence of digestive enzymes, responsive blood flow, and provides a rapid route to the central nervous system.

Eosinophilic granulomatosis with polyangiitis: understanding the disease and its management

Eosinophilic granulomatosis with polyangiitis is characterized by asthma, blood and tissue eosinophilia and small-vessel vasculitis. The clinical presentation is variable, but two main clinic-pathologic subsets can be distinguished: one hallmarked by positive ANCA and predominant 'vasculitic' manifestations (e.g. glomerulonephritis, purpura and mononeuritis multiplex) and the other by negative ANCA and prominent 'eosinophilic' manifestations (e.g. lung infiltrates and cardiomyopathy). The pathogenesis is not fully understood but probably results from the interplay between T and B cells and eosinophils. Eosinophilic granulomatosis with polyangiitis must be differentiated from several conditions, including hypereosinophilic syndromes and other small-vessel vasculitides. The overall survival is good; however, patients frequently relapse and have persistent symptoms. The recently developed monoclonal antibodies targeting B cells and eosinophilopoietic cytokines such as IL-5 are emerging as valid alternatives to conventional immunosuppressive therapies. In this review, we discuss the essential features of eosinophilic granulomatosis with polyangiitis, with particular respect to the most relevant issues concerning clinical presentation and management.

[Type-2 Asthma: Leaving Behind the Perspective of the Seventies]

Type-2 Asthma: Leaving Behind the Perspective of the Seventies Abstract. The diagnosis 'bronchial asthma' spans different phenotypes of this disease like an umbrella. The differentiation of these phenotypes and their overlaps is becoming increasingly important, as the phenotype-specific treatment approaches of today are not effective with every form of asthma. These approaches include the strategy of allergen avoidance, allergen immunotherapy and, most importantly, the newly available biologics for asthma. Treatable disease patterns, so-called 'treatable traits', require targeted diagnostics. The knowledge necessary to identify these traits still needs to be established in practice.

Are We Meeting the Promise of Endotypes and Precision Medicine in Asthma?

While the term asthma has long been known to describe heterogeneous groupings of patients, only recently have data evolved which enable a molecular understanding of the clinical differences. The evolution of transcriptomics (and other 'omics platforms) and improved statistical analyses in combination with large clinical cohorts opened the door for molecular characterization of pathobiologic processes associated with a range of asthma patients. When linked with data from animal models and clinical trials of targeted biologic therapies, emerging distinctions arose between patients with and without elevations in type 2 immune and inflammatory pathways, leading to the confirmation of a broad categorization of type 2-Hi asthma. Differences in the ratios, sources, and location of type 2 cytokines and their relation to additional immune pathway activation appear to distinguish several different (sub)molecular phenotypes, and perhaps endotypes of type 2-Hi asthma, which respond differently to broad and targeted anti-inflammatory therapies. Asthma in the absence of type 2 inflammation is much less well defined, without clear biomarkers, but is generally linked with poor responses to corticosteroids. Integration of "big data" from large cohorts, over time, using machine learning approaches, combined with validation and iterative learning in animal (and human) model systems is needed to identify the biomarkers and tightly defined molecular phenotypes/endotypes required to fulfill the promise of precision medicine.

Airway Remodeling in Asthma

Asthma is an inflammatory disease of the airways that may result from exposure to allergens or other environmental irritants, resulting in bronchoconstriction, wheezing, and shortness of breath. The structural changes of the airways associated with asthma, broadly referred to as airway remodeling, is a pathological feature of chronic asthma that contributes to the clinical manifestations of the disease. Airway remodeling in asthma constitutes cellular and extracellular matrix changes in the large and small airways, epithelial cell apoptosis, airway smooth muscle cell proliferation, and fibroblast activation. These pathological changes in the airway are orchestrated by crosstalk of different cell types within the airway wall and submucosa. Environmental exposures to dust, chemicals, and cigarette smoke can initiate the cascade of pro-inflammatory responses that trigger airway remodeling through paracrine signaling and mechanostimulatory cues that drive airway remodeling. In this review, we explore three integrated and dynamic processes in airway remodeling: (1) initiation by epithelial cells; (2) amplification by immune cells; and (3) mesenchymal effector functions. Furthermore, we explore the role of inflammaging in the dysregulated and persistent inflammatory response that perpetuates airway remodeling in elderly asthmatics.

In patients with severe asthma with eosinophilia in reslizumab clinical trials, high peripheral blood eosinophil levels are associated with low FEV1 reversibility

Background

A post hoc analysis of two randomized, placebo-controlled, Phase 3 trials of intravenous reslizumab, an anti-interleukin-5 (IL-5) biologic for severe eosinophilic asthma.

Methods

Relationships between baseline blood eosinophil levels (EOS), forced expiratory volume in 1 s (FEV₁) reversibility to β₂-agonists and treatment outcomes were assessed.

Results

Mean baseline FEV₁ reversibility was numerically lower among patients with high (≥ 400 cells/µL) versus low baseline EOS. Reslizumab produced clinically significant improvement in FEV₁, exacerbation rates and patient-reported outcomes after 52 weeks, including in patients with high EOS and low FEV₁ reversibility (≤ 14%) to β₂-agonists at baseline.

Conclusions

Clinical trial eligibility criteria stipulating minimum FEV₁ reversibility to β₂-agonists of ≥ 12% might exclude patients who would benefit from treatment with anti-IL-5 biologics.

Assessment of diagnostic accuracy of lung function indices and FeNO for a positive methacholine challenge

Demonstration of bronchial hyperresponsiveness is a key feature in asthma diagnosis. Methacholine challenge has proved to be a highly sensitive test to diagnose asthma in patients with chronic respiratory symptoms and preserved baseline lung function (FEV1 > 70% pred.) but is time consuming and may sometimes reveal unpleasant to the patient. We conducted a retrospective study on 270 patients recruited from the University Asthma Clinic of Liege. We have compared the values of several lung function indices and fractional exhaled nitric oxide (FeNO) in predicting a provocative methacholine concentration ≤16 mg/ml on a discovery cohort of 129 patients (57 already on ICS) and on a validation cohort of 141 patients (66 already on ICS). In the discovery study (n = 129), 85 patients (66%) had a positive methacholine challenge with PC20M ≤ 16 mg/ml. Those patients had lower baseline % predicted FEV1 (92% vs. 100%; p < 0.01), lower FEV1/FVC ratio (79% vs. 82%; p < 0.05), higher RV/TLC ratio (114% vs. 100%; p < 0,0001), lower SGaw (specific conductance) (0.76 vs. 0.95; p < 0,001) and higher FeNO (29 ppb vs. 19 ppb; p < 0,01). When performing ROC curve the RV/TLC ratio provided the greatest AUC (0.74, p < 0.001), sGAW had intermediate AUC of 0.69 (p < 0.001) while FeNO, FEV1 and FEV1/FVC ratio were modestly predictive (AUC of 0.65 (p < 0.05), 0,67 (p < 0.001) and 0,63 (p < 0.001). These results were confirmed in the validation study (n = 141). Based on a logistic regression analysis, significant variables associated with positive methacholine challenge were FeNO and RV/TLC (% Pred). A combined application of FeNO and RV/TLC (% Pred) for predicting the PC20M had a specificity of 85%, a sensitivity of 59% and an AUC of 0.79. In the validation study, three variables (RV/TLC, FeNO and FEV1) were independently associated with positive methacholine challenge and the combination of these three variables yielded a specificity of 77%, a sensitivity of 39% and an AUC of 0.77. The RV/TLC ratio combined to FeNO may be of interest to predict significant methacholine bronchial hyperresponsiveness.

Efficacy of mepolizumab treatment in oral corticosteroid-dependent severe eosinophilic asthma patients with chronic rhinosinusitis with nasal polyps: single center, real life study

Background/aim

Oral corticosteroid (OCS)-dependent severe eosinophilic asthma with chronic rhinosinusitis with nasal polyps (SEA-CRSwNP) would be a suitable phenotype for mepolizumab treatment. This study evaluated the short-term efficacy of mepolizumab treatment in OCS-dependent SEA-CRSwNP.

Materials and methods

Baseline and 24th week results [daily OCS doses, asthma exacerbation frequency, asthma control test (ACT) scores, blood eosinophil levels, FEV1 values, and numerical analog scale (NAS) of CRSwNP symptoms] of patients who were treated for at least 24 weeks with mepolizumab were retrospectively evaluated and compared.

Results

A total of 16 patients were enrolled in the study. Mepolizumab was discontinued in one patient due to side effects. The daily OCS dosage was reduced from baseline in all patients, and at week 24 OCS was discontinued in 40% of the patients (baseline mean steroid dose: 9.2 ± 5.2 mg, 24th week: 1.3 ± 1.4 mg; P < 0.001). The number of asthma exacerbations within 24 weeks significantly decreased after beginning mepolizumab treatment (2.1 ± 2.7 vs. 0.07 ± 0.26; P = 0.012), and a significant increase in ACT scores (baseline mean ACT: 18 ± 5.7; 24th week mean ACT: 23.3 ± 3; P = 0.006) was observed despite the decrease in daily OCS dosages. There was no significant difference in FEV1 values between baseline and week 24. Evaluation of the general symptoms of CRSwNP, as per NAS, revealed that the baseline mean NAS was 5.6 ± 4.4, and the 24th week mean NAS was 3.2 ± 3.2 (P = 0.021).

Conclusion

This is the first real-life study evaluating the short-term efficacy of mepolizumab treatment on OCS-dependent SEA-CRSwNP. This study demonstrates that mepolizumab is an effective and safe biologic for the treatment of this severe asthma subphenotype.

Increased CD69 expression on activated eosinophils in eosinophilic chronic rhinosinusitis correlates with clinical findings

BACKGROUND

Eosinophilic chronic rhinosinusitis (ECRS) is a subtype of chronic rhinosinusitis associated with asthma. CD69 is an important marker of activation for eosinophils. But, whether a correlation exist between the CD69 expression on eosinophils and clinical findings is unclear.

METHODS

We performed quantitative PCR and/or flow cytometry using tissue and purified eosinophils from the blood and nasal polyps of 12 patients with ECRS and from 8 patients without ECRS (controls). We assessed clinical findings including nasal polyp (NP) scores, sinus CT findings, and pulmonary function test results, and examined their possible association with the CD69 expression. We also performed CD69 cross-linking experiments in mouse eosinophils to investigate the functional role of CD69.

RESULTS

Levels of cytokine mRNAs (IL-4, -5, -10, and -13) were significantly higher in purified NP eosinophils and tissues from patients with ECRS than the levels of those in controls. The expressions of major basic protein (MBP), eosinophilic cationic protein (ECP), eosinophilic-derived neurotoxin (EDN), eosinophil peroxidase (EPX) in cytotoxic granules, and CD69 mRNA were significantly higher in purified eosinophils from NPs than in those from blood. We also found a correlation between expression of CD69 and clinical findings. Moreover, we found EPX release from mouse eosinophils following CD69 cross-linking.

CONCLUSIONS

These data suggest that increased CD69 expression by eosinophils is not only a biomarker for nasal obstruction and pulmonary dysfunction, but also a potential therapeutic target for patients with ECRS and asthma.

Three Major Efforts to Phenotype Asthma: Severe Asthma Research Program, Asthma Disease Endotyping for Personalized Therapeutics, and Unbiased Biomarkers for the Prediction of Respiratory Disease Outcome

The SARP, ADEPT, and U-BIOPRED programs are all significant efforts in characterizing asthma and reporting clusters that will assist in designing personalized therapies for asthma, and especially severe asthma. Key aspects of the design of these programs are summarized and major findings are reported in this review.

Mechanisms and Management of Asthma Exacerbations

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

Risk Factors for Acute Exacerbations in Elderly Asthma: What Makes Asthma in Older Adults Distinctive?

Purpose

Asthma in the elderly (EA; ≥ 65 years of age) is increasing, adding a heavy socioeconomic burden to the healthcare system. However, little is known about risk factors associated with acute exacerbations in EA patients. The objective of this study was to investigate risk factors for acute exacerbation in EA compared to non-elderly asthma (NEA).

Methods

We combined data from 3 adult asthma cohorts under a unified protocol and database. Asthmatic patients with regular follow-up during a 1-year period were selected from the cohorts to identify the risk factors predicting acute exacerbations in EA compared to NEA.

Results

We selected a total of 1,086 patients from the merged cohort. During the observation period, 503 and 583 patients were assigned to the EA and NEA groups, respectively. The exacerbation rate was 31.0% in the EA and 33.2% in the NEA group. Multivariate logistic regression analysis revealed fixed airway obstruction, chronic rhinosinusitis (CRS), and male sex as independent risk factors for exacerbation in the EA group. In the NEA group, exacerbation increased along with an increase in eosinophil count. Bayesian analysis of the interactions among clinical factors revealed that forced expiratory volume in 1 second/forced vital capacity was directly related to exacerbation in the EA group, and eosinophil count was related to exacerbation in the NEA group.

Conclusions

We suggest that fixed airway obstruction and CRS as the important clinical factors predicting acute exacerbations in EA, whereas in NEA, eosinophil count was the strong predictor of exacerbation.

The Intriguing Role of Interleukin 13 in the Pathophysiology of Asthma

Approximately 5–10% of asthmatic patients worldwide suffer from severe asthma. Experimental and clinical studies have demonstrated that IL-13 is an important cytokine in chronic airways inflammation. IL-13 is involved in Th2 inflammation and has been identified as a possible therapeutic target in the treatment of asthma. Two different human monoclonal antibodies (mAbs) anti-IL-13 (tralokinumab and lebrikizumab) block binding and signaling of IL-13 to its receptors, IL-13Rα1 and IL-13Rα2. Several randomized, double-blind, placebo-controlled multicenter studies have evaluated the safety and efficacy of tralokinumab and lebrikizumab in the treatment of adult patients with severe asthma, but all have failed to meet their primary endpoints. No serious adverse events related to the treatment with these anti-IL-13 mAbs have been reported in these studies. These negative clinical results contrast with positive findings from blocking IL-13 signaling in experimental models of asthma, raising doubts about the transferrable value of some models. Interestingly, dupilumab, a mAb which blocks both IL-4 and IL-13 signaling reduces exacerbation rates and improves lung function in severe asthmatics. These results suggest that IL-4 and IL-13 share some, but not all functional activities in airway inflammation. Tralokinumab might show efficacy in a highly selected cohort of asthmatics characterized by overexpression of IL-13.