Trends in worldwide asthma prevalence

Cost-effectiveness analysis of house dust mite allergen immunotherapy in children with allergic asthma

BACKGROUND

Cost-effectiveness studies evaluating allergen immunotherapy (AIT) in children are limited but needed to drive clinical and policy-making decisions such as reimbursement of new interventions. In this study, we compared the cost effectiveness of subcutaneous (SCIT) and sublingual immunotherapy (SLIT) tablets to the standard of care (SOC) treatment in children with house dust mite-driven (HDM) allergic asthma.

METHODS

We developed a hypothetical Markov model based on the Global Initiative for Asthma (GINA) severity steps to compare the three strategies over a 10-year horizon divided by cycles of 6 months. SOC was used as a reference to calculate the incremental cost-effectiveness ratio (ICER). Deterministic and probabilistic sensitivity analyses were used to assess models' uncertainty. Other scenarios were evaluated to strengthen the presentation of results.

RESULTS

The ICER for SCIT and SLIT tablets was 1281€ and 7717€, respectively. The cost-effectiveness threshold for Portugal was 18,482.80€; both treatment approaches were below this limit. The major contributors to these results were the AIT effects on reducing moderate and severe exacerbations and asthma controller medication. In the sensitivity analysis, SCIT revealed a higher probability of cost-effectiveness than SLIT. When including allergic rhinitis as comorbidity, ICER values reduced markedly, especially for SCIT intervention.

CONCLUSIONS

AIT was cost effective in children with HDM-driven allergic asthma, especially when given by the subcutaneous route. The high probability of cost effectiveness, especially for SCIT, may drive future policy decisions and AIT-prescribing habits. AIT adherence greatly influenced the results highlighting the value of implementing strategies to promote adherence rates.

Blockade of Mbd2 by siRNA-loaded liposomes protects mice against OVA-induced allergic airway inflammation via repressing M2 macrophage production

Objective

To address the role of methyl-CpG-binding domain 2 (MBD2) in the pathogenesis of asthma and its potential as a target for the asthmatic therapy.

Methods

Studies were conducted in asthmatic patients and macrophage-specific Mbd2 knockout mice to dissect the role of MBD2 in asthma pathogenesis. Additionally, RNAi-based therapy with Mbd2 siRNA-loaded liposomes was conducted in an ovalbumin (OVA)-induced allergic airway inflammation mouse model.

Results

Asthmatic patients and mice challenged with OVA exhibited upregulated MBD2 expression in macrophages, especially in alternatively activated (M2) macrophages. In particular, macrophage-specific knockout of Mbd2 protected mice from OVA-induced allergic airway inflammation and suppressed the M2 program. Notably, intratracheal administration of liposomes carrying Mbd2 siRNA decreased the expression of Mbd2 and prevented OVA-induced allergic airway inflammation in mice, as indicated by the attenuated airway inflammation and mucus production.

Conclusions

The above data indicate that Mbd2 implicates in the pathogenesis of asthma predominantly by regulating the polarization of M2 macrophages, which supports that Mbd2 could be a viable target for treatment of asthma in clinical settings.

Anti-inflammatory activities of Qingfei oral liquid and its influence on respiratory microbiota in mice with ovalbumin-induced asthma

Dysbiosis of respiratory microbiota is closely related to the pathophysiological processes of asthma, including airway inflammation. Previous studies have shown that Qingfei oral liquid (QF) can alleviate airway inflammation and airway hyper-responsiveness in respiratory syncytial virus-infected asthmatic mice, but its effect on the respiratory microbiota is unknown. We therefore aimed to observe the effects of QF on airway inflammation and respiratory microbiota in ovalbumin (OVA)-induced asthmatic mice. We also explored the potential mechanism of QF in reducing airway inflammation by regulating respiratory microbiota. Hematoxylin and eosin as well as periodic acid-Schiff staining were performed to observe the effects of QF on lung pathology in asthmatic mice. Cytokine levels in bronchoalveolar lavage fluid (BALF) specimens were also measured. Changes in respiratory microbiota were analyzed using 16S rRNA gene sequencing, followed by taxonomical analysis. In order to verify the metagenomic function prediction results, the expression of key proteins related to the MAPK and NOD-like receptor signaling pathways in the lung tissues were detected by immunohistochemistry. The current study found that QF had a significant anti-inflammatory effect in the airways of asthmatic mice. This is mainly attributed to a reduction in lung pathology changes and regulating cytokine levels in BALF. Analysis of the respiratory microbiota in asthmatic mice showed that the abundance of Proteobacteria at the phylum level and Pseudomonas at the genus level increased significantly and QF could significantly regulate the dysbiosis of respiratory microbiota in asthmatic mice. Metagenomic functional prediction showed that QF can downregulate the MAPK and Nod-like receptor signaling pathways. Immunohistochemical results showed that QF could downregulate the expression of p-JNK, p-P38, NLRP3, Caspase-1, and IL-1β, which are all key proteins in the signaling pathway of lung tissue. Our study therefore concluded that QF may reduce airway inflammation in asthmatic mice by regulating respiratory microbiota, and to the possibly downregulate MAPK and Nod-like receptor signaling pathways as its underlying mechanism.

Protective role of zinc in the pathogenesis of respiratory diseases

Respiratory diseases remain a major cause of morbidity and mortality worldwide. An imbalance of zinc, an essential trace element, is associated with a variety of lung diseases. We reviewed and summarized recent research (human subjects, animal studies, in vitro studies) on zinc in respiratory diseases to explore the protective mechanism of zinc from the perspective of regulation of oxidative stress, inflammation, lipid metabolism, and apoptosis. In the lungs, zinc has anti-inflammatory, antioxidant, and antiviral effects; can inhibit cancer cell migration; can regulate lipid metabolism and immune cells; and exerts other protective effects. Our comprehensive evaluation highlights the clinical and experimental effects of zinc in the pathogenesis of respiratory diseases. Our analysis also provides insight into the clinical application of zinc-targeted therapy for respiratory diseases.

Cost utility of Vitamin D supplementation in adults with mild to moderate asthma

IntroductionUncontrolled asthma significantly impairs health-related quality of life and work productivity. Some add-on therapies, such as vitamin D supplements, safely reduce the rate of asthma exacerbation. The purpose of this study was to assess the cost-utility of vitamin D supplementation in adults with mild to moderate persistent asthma in Colombia.MethodsA Markov model was created to estimate the cost and quality-adjusted life-years (QALYs) of patients with severe asthma in Colombia. Total costs and QALYs of two therapy strategies, vitamin D supplementation plus ICS versus ICS alone, were calculated over a one-year time horizon. Deterministic and probability sensitivity analyses were conducted, and cost-effectiveness was evaluated at a willingness-to-pay value of $5,180 per QALY gained.ResultsThe base-case analysis showed that compared with no supplementation, vitamin D supplementation was associated with higher costs and higher QALYs. The expected annual cost per patient with vitamin D supplementation was US$1338 and without this supplementation it was US$1095. The QALYs per person estimated with vitamin D supplementation was 0,80, and without this supplementation it was 0,63. The estimated incremental cost-effectiveness ratio (ICER) was US$1583 per QALY.ConclusionAdd-on vitamin D supplement was cost-effective when added to the usual care in patients with mild to moderate persistent asthma. Our study provides evidence that should be used by decision-makers to improve clinical practice guidelines.

Impact of yoga breathing and relaxation as an add-on therapy on quality of life, anxiety, depression and pulmonary function in young adults with bronchial asthma: A randomized controlled trial

BACKGROUND

The impact of combinations of yogic practices on bronchial asthma have been studied. Such yoga modules tend to be too lengthy for comfortable practice long-term, giving high dropouts. Returning to conventional medicine despite improvement is common. This study tested a shorter, easier yoga routine to improve asthma condition.

MATERIAL AND METHODS

Sixty young adults aged 18-30 years diagnosed with bronchial asthma of mild to moderate severity were randomly assigned to the Yoga Group, add-on yoga therapy and continuing prescribed medication, or the Control Group, continuing prescribed medication only. Measurements on days 0 and 90, included Asthma Quality of Life Questionnaire, Hamilton Anxiety Rating Scale, Beck's Depression Inventory and Pulmonary Function Tests. The yoga therapy module, practised 30 mins daily, included four kinds of yoga breathing practices, and ended with guided relaxation.

RESULTS

All Asthma Quality of Life subdomains improved greatly for the Yoga Group as did Hamilton Anxiety and Becks Depression Inventory scores, t statistics were high (40 -75), all p<.0001. Pulmonary Function also improved greatly in all variables, with smaller t statistics from 2 to 14. The Control Group showed some small improvements. Differences observed in scores were highly significant, with large effect sizes. Finally, no dropouts occurred.

DISCUSSION

Zero dropouts represents an unprecedented result. The yoga module was completely acceptable to participants, Yoga Group improvements were highly significant. The study indicates that the new yoga module effectively improves quality of life, levels of anxiety, depression and pulmonary function in young adults with above-stated bronchial asthma.

Maternal exposure to PM2.5/BC during pregnancy predisposes children to allergic rhinitis which varies by regions and exclusive breastfeeding

BACKGROUND

Increasing prevalence of childhood allergic rhinitis(AR) needs a deeper understanding on the potential adverse effects of early life exposure to air pollution.

OBJECTIVES

The main aim was to evaluate the effects of maternal exposure to PM_2.5 and chemical constituents during pregnancy on preschool children's AR, and further to explore the modification effects of regions and exclusive breastfeeding.

METHODS

A multi-center population-based study was performed in 6 cities from 3 regions of China in 2011-2012. Maternal exposure to ambient PM_2.5 and main chemical constituents(BC, OM, SO₄^2-, NO₃^-, NH₄⁺) during pregnancy was assessed and a longitudinal prospective analysis was applied on preschool children's AR. The modification effects of regions and exclusive breastfeeding were investigated.

RESULTS

A total of 8.8% and 9.8% of children reported doctor-diagnosed allergic rhinitis(DDAR) and current hay fever, respectively, and 48.6% had less than 6 months of exclusive breastfeeding. The means of PM_2.5 during pregnancy were 52.7 μg/m³, 70.3 μg/m³ and 76.4 μg/m³ in the east, north and central south of China, respectively. Multilevel log-binomial model regression showed that each interquartile range(IQR) increase of PM_2.5 during pregnancy was associated with an average increase in prevalence ratio (PR) of DDAR by 1.43(95% confidence interval(CI): 1.11, 1.84) and current hay fever by 1.79(95% CI: 1.26, 2.55), respectively. Among chemical constituents, black carbon (BC) had the strongest associations. Across 3 regions, the eastern cities had the highest associations, followed by those in the central south and the north. For those equal to or longer than 6 months of exclusive breastfeeding, the associations were significantly reduced.

CONCLUSIONS

Children in east of China had the highest risks of developing AR per unit increase of maternal exposure to PM_2.5 during pregnancy, especially BC constituent. Remarkable decline was found in association with an increase in breastfeeding for ≥6 months, in particular in east of China.

The Dynamic Contribution of Neutrophils in the Chronic Respiratory Diseases

Asthma, chronic obstructive pulmonary disease, and idiopathic pulmonary fibrosis are representative chronic respiratory diseases (CRDs). Although they differ in terms of disease presentation, they are all thought to arise from unresolved inflammation. Neutrophils are not only the first responders to acute inflammation, but they also help resolve the inflammation. Notably, emerging clinical studies show that CRDs are associated with systemic and local elevation of neutrophils. Moreover, murine studies suggest that airway-infiltrating neutrophils not only help initiate airway inflammation but also prolong the inflammation. Given this background, this review describes neutrophil-mediated immune responses in CRDs and summarizes the completed, ongoing, and potential clinical trials that test the therapeutic value of targeting neutrophils in CRDs. The review also clarifies the importance of understanding how neutrophils interact with other immune cells and how these interactions contribute to chronic inflammation in specific CRDs. This information may help identify future therapeutic strategies for CRDs.

Global, regional, and national prevalence of asthma in 2019: a systematic analysis and modelling study

Background

Asthma has a significant impact on people of all ages, particularly children. A lack of universally accepted case definition and confirmatory tests and a poor understanding of major risks interfere with a global response. We aimed to provide global estimates of asthma prevalence and cases in 2019 across four main epidemiological case definitions - current wheezing, ever wheezing, current asthma, and ever asthma. We further investigated major associated factors to determine regional and national distributions of prevalence and cases for current wheezing and ever asthma.

Methods

We identified relevant population-based studies published between January 1, 1990, and December 31, 2019. Using a multilevel multivariable mixed-effects meta-regression model, we assessed the age- and sex-adjusted associations of asthma with study-level variables, including year, setting, region and socio-demographic index (SDI). Using a random-effects meta-analysis, we then identified risk factors for current wheezing and asthma. From a "risk factor-based model", which included current smoking, and biomass exposure for current wheezing, and rural setting, current smoking, biomass exposure, and SDI for ever asthma, we estimated case numbers and prevalence across regions and 201 countries and territories in 2019.

Results

220 population-based studies conducted in 88 countries were retained. In 2019, the global prevalence estimates of asthma in people aged 5-69 years by various definitions, namely current wheezing, ever wheezing, current asthma, and ever asthma were 11.5% (95% confidence interval (CI) = 9.1-14.3), 17.9% (95% CI = 14.2-22.3), 5.4% (95% CI = 3.2-9.0) and 9.8% (95% CI = 7.8-12.2), respectively. These translated to 754.6 million (95% CI = 599. 7-943.4), 1181.3 million (95% CI = 938.0-1,471.0), 357.4 million (95% CI = 213.0-590.8), 645.2 million (95% CI = 513.1-806.2) cases, respectively. The overall prevalence of current wheezing among people aged 5-69 years was the highest in the African Region at 13.2% (95% CI = 10.5-16.5), and the lowest in the Americas Region at 10.0% (95% CI = 8.0-12.5). For ever asthma, the estimated prevalence in those aged 5-69 years was also the highest in the African Region at 11.3% (95% CI = 9.0-14.1), but the lowest in South-East Asia Region (8.8, 95% CI = 7.0-11.0).

Conclusions

Although varying approaches to case identification in different settings make epidemiological estimates of asthma very difficult, this analysis reaffirms asthma as a common global respiratory condition before the COVID-19 pandemic in 2019, with higher prevalence than previously reported in many world settings.

Levels of indoor particulate matter and association with asthma in children in Benin City, Nigeria

The relationship between indoor particulate matter and asthma in children was assessed in this study. Forty-five (45) locations were randomly selected across the five local government areas in Benin City, Edo State, for air quality assessment. Indoor and outdoor particulates (PM_1.0, PM_2.5, and PM₁₀) were monitored monthly using a handheld BLATN particulate sampler (Br-Smart-126S series). Reported clinical cases of asthma in children from 2008 to 2017 were collected from two major hospitals in the metropolis. The data obtained were analysed with SPSS for Windows version 21.0. The average concentrations of indoor and ambient PM ranged between 10.7-26.2 and 19.0-49.4 µg/m³ (PM_1.0), 27.4-59.6 and 45.6-93.0 µg/m³ (PM_2.5), and 33.5-67.9 and 60.9-106.1 µg/m³ (PM₁₀) in the wet and dry seasons. PM_2.5 and PM₁₀ concentrations were observed above the WHO standards. Indoor particulate concentration was significantly (p = 0.001-0.012) higher in the dry season across the locations. Outdoor PM correlated positively (R = 0.568-0.855, p < 0.05; R² = 0.322-0.724, p < 0.001) with their corresponding indoor PM concentration. The hazard ratio (HR) values of PM_2.5 and PM₁₀ exceeded 1 in all the sampling locations during the dry season, while the mean total hazard ratio (THR) of both PM metrics was considerably higher during the dry season than in the wet season. Indoor PM concentrations showed a significant positive correlation with reported cases of asthma (R = 0.498-0.542, p < 0.001) and accounted for 40.6% of the asthma cases during the dry season. The study showed that children in the selected households are at risk of increased asthma exacerbation due to exposure to particulate matter pollution.

Allergic disease, sleep problems and psychological distress in children recruited from the general community

BACKGROUND

It is unclear which allergic disease is most strongly related to which sleep problem and whether sleep problems may mediate the association between allergic disease and psychological distress. There is also a need for more community-based studies using non-referred samples.

OBJECTIVE

To examine the association between individual allergic diseases and sleep problems and test whether the association between allergic disease and psychological distress is mediated through sleep problems.

METHODS

Parents of 1449 Australian children aged 6-10y recruited from the general community completed measures of sleep problems (Pediatric Sleep Survey Instrument), psychological distress (Strengths and Difficulties Questionnaire), and frequency of allergic disease.

RESULTS

Sleep and psychological distress scores were in the normal range. After controlling for co-existing allergic diseases: allergic rhinitis was associated with sleep routine problems, morning tiredness, night arousals, sleep disordered breathing and restless sleep; asthma with sleep routine problems, sleep disordered breathing and restless sleep; and eczema with restless sleep. Path analyses revealed that sleep problems mediated the association between asthma and allergic rhinitis but not eczema with psychological distress.

CONCLUSION

In this non-referred community sample, the frequency of sleep problems and psychological distress was lower than that typically reported in children referred to specialized centres. However, allergic rhinitis was associated with a broad range of sleep problems and to a lesser extent in children with asthma and least in children with eczema. Path analysis revealed that the association between allergic disease and psychological distress was mediated through sleep problems highlighting the importance of assessing sleep health in children with allergic disease.

Effectiveness and safety of a microcrystalline tyrosine‐adjuvanted Dermatophagoides pteronyssinus allergoid immunotherapy in adult patients with allergic asthma and rhinitis: A real‐life prospective observational study

Introduction

Although clinical trials have shown the efficacy and safety of allergen‐specific immunotherapy (AIT) in the treatment of allergic asthma, there is a need for real‐life studies. We aimed to assess the effectiveness and safety of a microcrystalline tyrosine‐adjuvanted Dermatophagoides pteronyssinus allergoid (Acarovac Plus®) in patients with house dust mite (HDM)‐induced allergic asthma in a real‐life study.

Methods

A subanalysis of a multicenter, prospective, observational, real‐life study. Patients with rhinitis and allergic asthma caused by HDMs were assessed before AIT with Acarovac Plus® and at 6 and 12 months after this treatment. Assessment parameters were percentage of days with asthma symptoms, percentage of days on asthma medication, classification of asthma according to Spanish guidelines for the management of asthma, asthma‐related quality of life (quality of life in adults with asthma questionnaire [QLAAQ]), perception of symptoms (visual analog scale [VAS]), and treatment satisfaction (treatment satisfaction questionnaire for medication [TSQM]). Safety was assessed by the number and severity of adverse reactions.

Results

This subanalysis included 55 patients. Treatment with Acarovac Plus® showed significant differences in the analyzed variables when the baseline visit was compared with the 12‐month visit: reduction of the mean (SD) percentage of days with asthma symptoms (23.9 [9.2] vs. 5.1 [12.8]; p = .002), of the mean [SD] percentage of days on asthma medication (67.6 [42.9] vs. 45.1 [46.8]; p = .002), and of the percentage of patients with persistent asthma (78.2% vs. 38.9%; p = .009). Acarovac Plus® significantly improved asthma‐related quality of life, as shown by a decrease of 1.39 points in QLAAQ score at 12 months (p < .001), and in the subjective perception of symptoms on the VAS (−3.50, p < .0001). Patients showed high treatment satisfaction according to the TSQM, and it was well tolerated. No serious adverse events were reported.

Conclusions

Acarovac Plus® was effective and safe for the treatment of patients with HDM‐induced allergic asthma in a real‐life study.

Mediterranean-Type Diets as a Protective Factor for Asthma and Atopy

We are currently riding the second wave of the allergy epidemic, which is ongoing in affluent societies, but now also affecting developing countries. This increase in the prevalence of atopy/asthma in the Western world has coincided with a rapid improvement in living conditions and radical changes in lifestyle, suggesting that this upward trend in allergic manifestations may be associated with cultural and environmental factors. Diet is a prominent environmental exposure that has undergone major changes, with a substantial increase in the consumption of processed foods, all across the globe. On this basis, the potential effects of dietary habits on atopy and asthma have been researched rigorously, but even with a considerable body of evidence, clear associations are far from established. Many factors converge to obscure the potential relationship, including methodological, pathophysiological and cultural differences. To date, the most commonly researched, and highly promising, candidate for exerting a protective effect is the so-called Mediterranean diet (MedDi). This dietary pattern has been the subject of investigation since the mid twentieth century, and the evidence regarding its beneficial health effects is overwhelming, although data on a correlation between MedDi and the incidence and severity of asthma and atopy are inconclusive. As the prevalence of asthma appears to be lower in some Mediterranean populations, it can be speculated that the MedDi dietary pattern could indeed have a place in a preventive strategy for asthma/atopy. This is a review of the current evidence of the associations between the constituents of the MedDi and asthma/atopy, with emphasis on the pathophysiological links between MedDi and disease outcomes and the research pitfalls and methodological caveats which may hinder identification of causality. MedDi, as a dietary pattern, rather than short-term supplementation or excessive focus on single nutrient effects, may be a rational option for preventive intervention against atopy and asthma.

Preventing allergies through the skin

OBJECTIVE

To inform readers of the current and forthcoming skin barrier interventions that have clinically relevant implications in the prevention of allergic sensitization and atopic diseases.

DATA SOURCES

Peer-reviewed journal articles indexed on PubMed and clinical trials referenced on clinicaltrials.gov were analyzed.

STUDY SELECTIONS

Literature searches from PubMed and clinicaltrials.gov were performed using combinations of the following search terms: prevention, allergy, atopy, skin, cutaneous, microbiome, microbiota, Staphylococcus aureus, atopic dermatitis, eczema, food allergy, and asthma.

RESULTS

The skin barrier represents an entry point for allergic sensitization and T_H2-mediated allergic disorders. Results from clinical trials designed to improve microbiome complexity and reduce S aureus colonization, provide skin barrier enhancement, and deliver epicutaneous immunotherapy are summarized and discussed in the context of primary, secondary, and tertiary prevention of allergic disease.

CONCLUSION

The skin barrier is a promising target for prevention of allergic disease, though clinical trial results thus far have been mixed, at best.

Concentrations of indoor gaseous air pollutants and risk factors associated with childhood asthma in Benin City, Nigeria

Pollutants from various indoor sources account for indoor air pollution mostly in developing countries and pose health risks to children. This study assessed the levels of indoor gaseous pollutants and environmental risk factors associated with asthma in children. A cross-sectional household survey was conducted among 304 children between the ages of 1 and 17 years. Indoor pollution at home was investigated using a modified international survey on asthma and allergies in childhood (ISAAC) questionnaire. Concentrations of indoor gaseous pollutants (CO, SO2 and NO2) were measured in two hundred and twenty-five randomly selected households using a MultiRae lite gas meter. The data obtained were analysed using SPSS for windows version 21.0. The risk factors for childhood asthma were obtained as odds ratios (ORs) using multivariate logistic regression. Mean concentrations of indoor gaseous pollutants ranged between 2.34-3.14 and 2.21-2.61 mg/m³ (CO), 0.02-0.05 and < 0.002-0.03 mg/m³ (NO2) and < 0.002-0.03 and < 0.002-0.02 mg/m³ (SO2) in the wet and dry seasons. The mean values of pollutants were within the WHO permissible limits. The morbidity rates of clinical asthma, physician-diagnosed asthma and recurrent wheeze in the past 12 months among the respondents were 5.6%, 2.6% and 11.8% respectively. There was no association between asthma prevalence and air pollutant exposures except with CO (R = 0.130). However, the number of occupants, family history of asthma, current smoking, use of kerosene and proximity of residence to the highway with significant (p < 0.05) odds ratios (12.4, 3.51, 2.51, 7.20 and 3.46) were independent contributors to current asthma in children. The study showed that exposure to household risk factors contributed to increased asthma among children in the study locations.

Asthma in the Americas: An Update: A Joint Perspective from the Brazilian Thoracic Society, Canadian Thoracic Society, Latin American Thoracic Society, and American Thoracic Society

Asthma affects a large number of people living in the Americas, a vast and diverse geographic region comprising 35 nations in the Caribbean and North, Central, and South America. The marked variability in the prevalence, morbidity, and mortality from asthma across and within nations in the Americas offers a unique opportunity to improve our understanding of the risk factors and management of asthma phenotypes and endotypes in children and adults. Moreover, a better assessment of the causes and treatment of asthma in less economically developed regions in the Americas would help diagnose and treat individuals migrating from those areas to Canada and the United States. In this focused review, we first assess the epidemiology of asthma, review known and potential risk factors, and examine commonalities and differences in asthma management across the Americas. We then discuss future directions in research and health policies to improve the prevention, diagnosis, and management of pediatric and adult asthma in the Americas, including standardized and periodic assessment of asthma burden across the region; large-scale longitudinal studies including omics and comprehensive environmental data on racially and ethnically diverse populations; and dissemination and implementation of guidelines for asthma management across the spectrum of disease severity. New initiatives should recognize differences in socioeconomic development and health care systems across the region while paying particular attention to novel or more impactful risk factors for asthma in the Americas, including indoor pollutants such as biomass fuel, tobacco use, infectious agents and the microbiome, and psychosocial stressor and chronic stress.

Fermented Food in Asthma and Respiratory Allergies—Chance or Failure?

In the last few decades, a dramatic increase in the global prevalence of allergic diseases and asthma was observed. It was hypothesized that diet may be an important immunomodulatory factor influencing susceptibility to allergic diseases. Fermented food, a natural source of living microorganisms and bioactive compounds, has been demonstrated to possess health-promoting potentials and seems to be a promising strategy to reduce the risk of various immune-related diseases, such as allergic diseases and asthma. The exact mechanisms by which allergic diseases and asthma can be alleviated or prevented by fermented food are not well understood; however, its potential to exert an effect through modulating the immune response and influencing the gut microbiota has been recently studied. In this review, we provide the current knowledge on the role of diet, including fermented foods, in preventing or treating allergic diseases and asthma.

Influence of Maternal Fish Oil Supplementation on the Risk of Asthma or Wheeze in Children: A Meta-Analysis of Randomized Controlled Trials

Background

Previous studies evaluating the influences of maternal fish oil supplementation on the risk of asthma or wheeze in children showed inconsistent results. We performed a meta-analysis or randomized controlled trials (RCTs) to systematically evaluate the efficacy of maternal fish oil supplementation for asthma or wheeze.

Methods

Relevant RCTs were obtained by search of PubMed, Embase, and Cochrane's Library databases. A random-effects model incorporating the potential publication bias was used to pool the results.

Results

Ten RCTs with 3,676 infants were included. Compared to control, maternal supplementation with fish oil was not associated with a reduced risk of asthma or wheeze [odds ratio (OR): 0.91, 95% confidence interval (CI): 0.72-1.14, P = 0.40] with mild heterogeneity (I 2 = 28%). Subgroup analyses showed that maternal fish oil supplementation significantly reduced the risk of asthma (OR: 0.56, 95% CI: 0.35-0.91, P = 0.02; I 2 = 0%), but not the risk of wheeze (OR: 1.12, 95% CI: 0.90-1.41, P = 0.32; I 2 = 0%). In addition, maternal fish oil supplementation was associated with reduced risk of asthma or wheeze in high-dose studies (≥1,200 mg/d, OR: 0.65, 95% CI: 0.48-0.87, P = 0.003; I 2 = 0%), but not in low-dose studies (<1,200 mg/d, OR: 1.10, 95% CI: 0.88-1.38, P = 0.39; I 2 = 0%, P for subgroup difference = 0.005). Study characteristics such as the risk of the infants, timing of supplementation, and follow-up duration did not significantly affect the results.

Conclusions

Maternal fish oil supplementation may reduce the risk of clinically diagnosed asthma in children, particularly with high-dose fish oil.

Involvement and therapeutic implications of airway epithelial barrier dysfunction in type 2 inflammation of asthma

Type 2 inflammation is a complex immune response and primary mechanism for several common allergic diseases including allergic rhinitis, allergic asthma, atopic dermatitis, and chronic rhinosinusitis with nasal polyps. It is the predominant type of immune response against helminths to prevent their tissue infiltration and induce their expulsion. Recent studies suggest that epithelial barrier dysfunction contributes to the development of type 2 inflammation in asthma, which may partly explain the increasing prevalence of asthma in China and around the globe. The epithelial barrier hypothesis has recently been proposed and has received great interest from the scientific community. The development of leaky epithelial barriers leads to microbial dysbiosis and the translocation of bacteria to inter- and sub-epithelial areas and the development of epithelial tissue inflammation. Accordingly, preventing the impairment and promoting the restoration of a deteriorated airway epithelial barrier represents a promising strategy for the treatment of asthma. This review introduces the interaction between type 2 inflammation and the airway epithelial barrier in asthma, the structure and molecular composition of the airway epithelial barrier, and the assessment of epithelial barrier integrity. The role of airway epithelial barrier disruption in the pathogenesis of asthma will be discussed. In addition, the possible mechanisms underlying the airway epithelial barrier dysfunction induced by allergens and environmental pollutants, and current treatments to restore the airway epithelial barrier are reviewed.

Development and Content Validation of a Comprehensive Health Literacy Survey Instrument for Use in Individuals with Asthma during the COVID-19 Pandemic

Individuals with chronic conditions have been faced with many additional challenges during the COVID-19 pandemic. Individual health literacy (HL) as the ability to access, understand, evaluate, and apply pandemic-related information has thus become ever more important in these populations. The purpose of this study was to develop and content-validate a comprehensive HL survey instrument for people with asthma based on an integrated framework, and on previous surveys and other instruments for use in the general population and vulnerable groups. Beside HL, assumed determinants, mediators, and health outcomes were embraced in the framework. A mixed-method design was used. A comprehensive examination of the available literature yielded an initial pool of 398 single items within 20 categories. Based on content validity indices (CVI) of expert ratings (n = 11) and the content analysis of cognitive interviews with participants (n = 9), the item pool was reduced, and individual items/scales refined or modified. The instrument showed appropriate comprehensibility (98.0%), was judged relevant, and had an acceptable CVI at scale level (S-CVI/Ave = 0.91). The final version comprises 14 categories measured by 38 questions consisting of 116 single items. In terms of content, the instrument appears a valid representation of behavioural and psychosocial constructs pertaining to a broad HL understanding and relevant to individuals with asthma during the COVID-19 pandemic. Regular monitoring of these behavioural and psychosocial constructs during the course of the pandemic can help identify needs as well as changes during the course of the pandemic, which is particularly important in chronic disease populations.

Prevalence, Deaths, and Disability-Adjusted Life-Years Due to Asthma and Its Attributable Risk Factors in 204 Countries and Territories, 1990-2019

BACKGROUND

Understanding global trends in the point prevalence, deaths, and disability-adjusted life-years (DALYs) for asthma will facilitate evidence-based decision-making.

RESEARCH QUESTION

What are the global, regional, and national burdens of asthma in 204 countries and territories between 1990 and 2019 by age, sex, and sociodemographic index (SDI)?

STUDY DESIGN AND METHODS

Publicly available data from the Global Burden of Disease study from 1990 through 2019 were used. All estimates were presented as counts and age-standardized rates per 100,000, along with their associated uncertainty intervals.

RESULTS

In 2019, the global age-standardized point prevalence and death rates for asthma were 3,415.5 and 5.8 per 100,000, which represent a 24% and 51.3% decrease since 1990, respectively. Moreover, in 2019, the global age-standardized DALY rate was 273.6 and the global point prevalence of asthma was highest in the group 5 to 9 years of age. Also in 2019, the United States (10,399.3) showed the highest age-standardized point prevalence rate of asthma. Generally, the burden of asthma decreased with increasing SDI. Globally, high BMI (16.9%), smoking (9.9%), and occupational asthmagens (8.8%) contributed to the 2019 asthma DALYs.

INTERPRETATION

Asthma remains an important public health issue, particularly in regions with low socioeconomic development. Future research is needed to examine thoroughly the associations asthma has with its risk factors and the factors impeding optimal self-management. Further research also is needed to understand and implement better the interventions that have reduced the burden of asthma.

Precision medicine in the allergy clinic: the application of component resolved diagnosis

INTRODUCTION

A precise diagnosis is key for the optimal management of allergic diseases and asthma. In vivo or in vitro diagnostic methods that use allergen extracts often fail to identify the molecules eliciting the allergic reactions.

AREAS COVERED

Component-resolved diagnosis (CRD) has solved most of the limitations of extract-based diagnostic procedures and is currently valuable tool for the precision diagnosis in the allergy clinic, for venom and food allergy, asthma, allergic rhinitis, and atopic dermatitis. Its implementation in daily practice facilitates: a) the distinction between genuine multiple sensitizations and cross-reactive sensitization in polysensitized patients; b) the prediction of a severe, systemic reaction in food or insect venom allergy; c) the optimal selection of allergen immunotherapy based on the patient sensitization profile. This paper describes its main advantages and disadvantages, cost-effectiveness and future perspectives.

EXPERT OPINION

The diagnostic strategy based on CRD is part of the new concept of precision immunology, which aims to improve the management of allergic diseases.

The Effect of Vitamin D Supplementation in Children With Asthma: A Meta-Analysis

BACKGROUND

An increasing number of studies have suggested that vitamin D can be used to treat childhood asthma, but its clinical effects are still unclear. We conducted this meta-analysis to examine the latest estimates of the effectiveness and safety of using vitamin D to treat childhood asthma.

METHODS

The PubMed, The Cochrane Library, ScienceDirect, Embase, Scopus, Ovid MEDLINE, Web of Science, and Google Scholar databases were searched for randomized controlled trials (RCTs) describing vitamin D supplementation interventions for asthmatic children. Asthma exacerbation, vitamin D levels, the predicted percentage of forced expiratory volume in the first second (FEV1%) and adverse effects (AEs) were analyzed as the main outcome measures.

RESULTS

After screening, eight RCTs with 738 children were included. Compared with placebos, vitamin D supplementation had a stronger effect on serum vitamin D levels [mean difference (MD) = 13.51 (4.24, 22.79), p = 0.004]. The pooled results indicated that no significant changes were found between the groups in asthma control, as measured by adopting the following indicators: asthma exacerbation [risk ratio (RR) = 0.92 (0.68, 1.25), p = 0.60]; Childhood Asthma Control Test (CACT) scores [MD = 0.15 (-0.43, 0.74), p = 0.61]; hospitalizations for asthma exacerbation [RR = 1.20 (0.48, 2.96), p = 0.70]; acute care visits [RR = 1.13 (0.77, 1.65), p = 0.63]; steroid use [RR = 1.03 (0.41, 2.57), p = 0.95]; and fractional exhaled nitric oxide (FeNO) [MD =-3.95 (-22.87, 14.97), p = 0.68]. However, vitamin D supplementation might reduce the FEV1% [MD = -4.77 (-9.35, -0.19), p = 0.04] and the percentage of predicted forced vital capacity (FVC%) [MD =-5.01 (-9.99, -0.02), p = 0.05] in patients. Subgroup analysis revealed no difference in AEs between the two groups.

CONCLUSIONS

Vitamin D supplementation significantly increased patients' serum vitamin D levels, but it had no benefit for asthma control. However, vitamin D supplementation might reduce patients' lung function. It is essential to systemically search for more large-scale, rigorous, and well-designed RCTs to fully confirm these conclusions.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021288838, PROSPERO CRD42021288838.

The Burden of Childhood Asthma by Age Group, 1990-2019: A Systematic Analysis of Global Burden of Disease 2019 Data

BACKGROUND

Asthma is a common respiratory disease in children. We aimed to update information about the incidence and mortality and disability-adjusted life years (DALYs) of childhood asthma and provide evidence-based recommendations for childhood asthma prevention.

METHODS

Data were obtained from the Global Burden of Disease (GBD) study, which was conducted from 1990 to 2019 in 204 countries. First, we estimated incidence, mortality and DALY rates of childhood asthma using a Bayesian meta-regression model. Second, we analyzed the relationship between the sociodemographic index (SDI) and DALYs in different age groups. Third, we studied changes in trends of the age-standardized DALY rate between 1990 and 2019 based on age group, SDI, and risk factors.

RESULTS

Globally, the number of deaths due to childhood asthma and the incidence and DALY rates were 12.9 thousand (95% UI 10.6 to 15.7), 22 million (95% UI 15 to 31), and 5.1 million (95% UI 3.4 to 7.5) in 2019, decreasing by 65.1% (95% UI 47.6 to 72.4), 5.3% (95% UI 2.6 to 8.8) and 30% (95% UI 18 to 41) from those in 1990, respectively. With the exception of high-SDI regions, the age-standardized DALY rate in all age groups in all SDI regions declined. In 2019, the age-standardized DALY rate in 1- to 4-year-old individuals was highest in low-SDI regions and that of 5- to 19-year-old individuals was highest in high-SDI regions. In contrast to low-SDI regions, individuals in high-SDI regions had a higher risk of DALYs due to asthma, except in those aged 1 to 4 years. A high body mass index (BMI) was a stronger risk factor than occupational asthmagens for childhood asthma.

CONCLUSION

Our findings provide insight into asthma prevention and treatment through the identification of key factors related to childhood asthma. Based on the data available, different risk factors according to age group and region/country suggest different prevention strategies, which is key for preventing childhood asthma.

Prevalence of Asthma and Its Associating Environmental Factors among 6-12-Year-Old Schoolchildren in a Metropolitan Environment-A Cross-Sectional, Questionnaire-Based Study

We aimed to evaluate the prevalence of asthma and its associating environmental factors within a 6–12-year-old population. A cross-sectional, questionnaire-based study was conducted in primary schools located in the capital of Hungary; 3836 eligible parent-reported questionnaires were evaluated. Besides the International Study of Asthma and Allergies in Childhood (ISAAC) phase three core questions for asthma, the survey also assessed various potential risk factors. We introduced the umbrella term cumulative asthma as the union of physician-diagnosed asthma and current wheezing to estimate the lifetime prevalence of asthma. Current wheezing and physician-diagnosed asthma showed a frequency of 9.5% and 6.3%, respectively. They contributed to a cumulative asthma prevalence of 12.6% among the sampled population, with a girl-boy percentage of 37.4% to 62.6%. Air-pollution and weedy areas were associated with greater risk for asthma, while a suburban residence showed lesser odds. Indoor smoking, visible mold, and keeping a dog were defined as risk factors for asthma, while the presence of plants in the bedroom and pet rodents were associated with lower odds ratios. The consumption of fast food, beverages containing additives and margarine were significantly higher in asthmatics, while we found frequent sport activity and cereal intake associated with lower odds ratios for asthma. In this urban environment, we identified an increased asthma prevalence compared to some previously published studies, but the cross-sectional design and the different methodology did not permit us to draw timeframe-dependent conclusions.

Cost-utility analysis of dupilumab add on therapy versus standard therapy in adolescents and adults for severe asthma in Colombia

INTRODUCTION

Dupilumab is a recombinant human IgG4 monoclonal antibody that inhibits IL-4 and IL-13 signaling. This drug raises concerns about the economic impact in scenarios with constrained resources. This study aimed to estimate the cost-utility of dupilumab plus standard care (SoC) vs SoC alone in adolescents and adults with severe asthma and eosinophilic phenotype.

METHODS

A probabilistic Markov model was created to estimate the cost and quality-adjusted life-years (QALYs) of patients with uncontrolled allergic asthma in Colombia. Total costs and QALYs of standard therapy (ICS + LABA), add-on therapy with dupilumab, were calculated over a lifetime horizon. Multiple sensitivity analyses were conducted. Cost-effectiveness was evaluated at a willingness-to-pay (WTP) value of $19,000.

RESULTS

The base-case analysis showed dupilumab was associated with higher annual annual per-patient costs (US$5,719 for dupilumab and US$1,214 for standard therapy) and higher QALYs than standard therapy (fe  4.06 QALYs vs 3.97 QALYs, respectively). . The incremental cost-effectiveness ratio estimated was US$50,160 per QALY gained.

CONCLUSION

Dupilumab is not cost-effective using a WTP of US$19000 per QALY threshold in Colombia. Our study provides evidence that should be used by decision-makers to improve clinical practice guidelines and should be replicated to validate their results in other middle-income countries.

Cost-utility of as-needed combination low-dose budesonide-formoterol in adolescents mild asthma

BACKGROUND

Previously evidence has demonstrated that as-needed combination low-dose budesonide-formoterol reduced the risk of severe exacerbations compared with short-acting β2-agonist (SABA) reliever therapy in an adolescent with mild asthma. Concerns as if the extra benefit offered by this drug outweighs the additional cost. This study aimed to evaluate the cost-effectiveness of as-needed combination low-dose budesonide-formoterol compared with short-acting β2-agonist (SABA) reliever therapy in adolescents with mild asthma in Colombia.

METHODS

A probabilistic Markov model was created to estimate the cost and quality-adjusted life-years (QALYs) of patients with mild asthma in Colombia. Total costs and QALYs of low-dose budesonide-formoterol compared with short-acting β2-agonist (SABA) were calculated over a lifetime horizon. Multiple sensitivity analyses were conducted. Cost-effectiveness was evaluated at a willingness-to-pay value of $19,000.

RESULTS

The model suggests a potential gain of 0.03 QALYs and per patient per year on low-dose budesonide-formoterol. The cost difference per person was US$-4 per patient per year in favor of budesonide- formoterol. The position of dominance negates the need to calculate an incremental cost-effectiveness ratio. In the one-way and probabilistic sensitivity analyses, our base-case results were robust to variations of all assumptions and parameters.

CONCLUSION

In conclusion, low-dose budesonide-formoterol as a reliever was found to be cost-effective when added to usual care in adolescents with mild asthma. This evidence should promote economic evaluations in developed and developing countries for the inclusion of new drugs in health insurance plans.

Prenatal low-dose antibiotic exposure and children allergic diseases at 4 years of age: A prospective birth cohort study

BACKGROUND

Based on a medical record or questionnaire survey approach, previous epidemiological studies have investigated associations between maternal antibiotic exposure during pregnancy and childhood allergic diseases. However, biomonitoring studies on the prenatal low-dose antibiotic exposure, mainly from the environment and contaminated food, and in relation to children allergic diseases, are missing.

OBJECTIVES

This research aimed to examine the associations between prenatal low-dose antibiotic exposure measured at multiple time points and children current allergic diseases at 4 years of age.

METHODS

The current study including 2453 mother-child pairs was based on the Ma'anshan Birth Cohort study. Selected 41 antibiotics and their two metabolites, which including human antibiotics (HAs), preferred as human antibiotics (PHAs), veterinary antibiotics (VAs) and preferred as veterinary antibiotics (PVAs), in urine samples from 2453 pregnant women were biomonitored through liquid chromatography-triple quadrupole tandem mass spectrometry. Information on children current allergic diseases were collected via validated questionnaires. Generalized estimating equation were used to explore the associations between the repeated measurements of maternal urinary antibiotic over three trimesters and current allergic diseases in children.

RESULTS

The detection rates of nine individual antibiotics in the three trimester during pregnancy are greater than 10%, and the 90th percentile concentration of the detected antibiotics ranges from 0.07 to 22.34 µg/g, and the 95th percentile concentration ranges from 0.17 to 59.57 µg/g. Among the participants, each one-unit concentration increment of sulfamethazine (adjusted OR=1.28, 95% CI: 1.10, 1.49, P-_FDR=0.014) in the first trimester and ciprofloxacin (adjusted OR=1.17, 95% CI: 1.07, 1.28, P-_FDR=0.008) in the second trimester were associated with an increased risk of current eczema in children. In the third trimester, each one-unit concentration increment of oxytetracycline (adjusted OR=1.90, 95% CI: 1.30, 2.78, P-_FDR=0.014) was associated with an increased risk of current asthma in children. Gender-stratified analyses demonstrated that no gender differences were observed in the associations between prenatal antibiotic exposure and current allergic diseases in children.

CONCLUSIONS

Maternal exposure to certain specific VAs or PVAs (sulfamethazine, ciprofloxacin and oxytetracycline) in different trimesters was associated with an increased risk of current asthma and current eczema in 4-year-old children. No gender differences were found in these associations. Further studies are warranted to confirm our findings and explore the potential mechanisms.

Association Between Asthma and Migraine: A Systematic Review and Meta-Analysis of Observational Studies

Objectives: The purpose of this study was to determine the association between asthma and migraine and assess the risk for migraine in patients with asthma. Methods: We systematically searched the Cochrane Library, PubMed, Medical Literature Analysis and Retrieval System Online (MEDLINE), and Excerpta Medica dataBASE (EMBASE) databases from inception to September 26, 2021, for indexed observational studies that examined either the odds or risk of migraine in subjects with asthma. The qualities of the included studies were evaluated using the Newcastle-Ottawa Scale. A random-effects meta-analysis was performed to calculate the odds ratio for case-control and cross-sectional studies and the risk ratio for cohort studies. Results: Seven observational studies (four cross-sectional and three cohort studies) with a total of 549,534 study subjects were included in this systematic review and meta-analysis and selected for data extraction. Four articles were considered to be of moderate quality; other studies were considered to be of high quality. Asthma was associated with increased odds (OR, 1.85; 95%CI, 1.39-2.45) and risk of migraine (RR, 1.70; 95%CI, 1.52-1.90). Conclusions: The available evidence that supports the existence of an association between asthma and migraine is limited. Clinicians should be aware that patients with asthma show both increased prevalence and incidence of migraine. Further studies are warranted to further clarify the relationship between asthma and migraine. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=185881, identifier: CRD42020185881.

Differential Regulation of the Asthmatic Phenotype by the Aryl Hydrocarbon Receptor

The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that regulates the metabolism of xenobiotics. There is growing evidence that the AhR is implicated in physiological processes such proliferation, differentiation, and immune responses. Recently, a role of the AhR in regulating allergic asthma has been suggested, but whether the AhR also regulates other type of asthma, particularly occupational/irritant-induced asthma, remains unknown. Using AhR-deficient (Ahr^−/−) mice, we compared the function of the AhR in the response to ovalbumin (OVA; allergic asthma) vs. chlorine (Cl₂; irritant-induced asthma) exposure. Lung inflammation and airway hyperresponsiveness were assessed 24h after exposure to Cl₂ or OVA challenge in Ahr^−/− and heterozygous (Ahr^+/−) mice. After OVA challenge, absence of AhR was associated with significantly enhanced eosinophilia and lymphocyte influx into the airways of Ahr^−/− mice. There were also increased levels of interleukin-4 (IL-4) and IL-5 in the airways. However, OVA-induced airway hyperresponsiveness was not affected. In the irritant-induced asthma model caused by exposure to Cl₂, the AhR did not regulate the inflammatory response. However, absence of AhR reduced Cl₂-induced airway hyperresponsiveness. Collectively, these results support a differential role for the AhR in regulating asthma outcomes in response to diverse etiological agents.

Worldwide trends in the burden of asthma symptoms in school-aged children: Global Asthma Network Phase I cross-sectional study

BACKGROUND

Asthma is the most common chronic disease in children globally. The Global Asthma Network (GAN) Phase I study aimed to determine if the worldwide burden of asthma symptoms is changing.

METHODS

This updated cross-sectional study used the same methods as the International study of Asthma and Allergies in Childhood (ISAAC) Phase III. Asthma symptoms were assessed from centres that completed GAN Phase I and ISAAC Phase I (1993-95), ISAAC Phase III (2001-03), or both. We included individuals from two age groups (children aged 6-7 years and adolescents aged 13-14 years) who self-completed written questionnaires at school. We estimated the 10-year rate of change in prevalence of current wheeze, severe asthma symptoms, ever having asthma, exercise wheeze, and night cough (defined by core questions in the questionnaire) for each centre, and we estimated trends across world regions and income levels using mixed-effects linear regression models with region and country income level as confounders.

FINDINGS

Overall, 119 795 participants from 27 centres in 14 countries were included: 74 361 adolescents (response rate 90%) and 45 434 children (response rate 79%). About one in ten individuals of both age groups had wheeze in the preceding year, of whom almost half had severe symptoms. Most centres showed a change in prevalence of 2 SE or more between ISAAC Phase III to GAN Phase I. Over the 27-year period (1993-2020), adolescents showed a significant decrease in percentage point prevalence per decade in severe asthma symptoms (-0·37, 95% CI -0·69 to -0·04) and an increase in ever having asthma (1·25, 0·67 to 1·83) and night cough (4·25, 3·06 to 5·44), which was also found in children (3·21, 1·80 to 4·62). The prevalence of current wheeze decreased in low-income countries (-1·37, -2·47 to -0·27], in children and -1·67, -2·70 to -0·64, in adolescents) and increased in lower-middle-income countries (1·99, 0·33 to 3·66, in children and 1·69, 0·13 to 3·25, in adolescents), but it was stable in upper-middle-income and high-income countries.

INTERPRETATION

Trends in prevalence and severity of asthma symptoms over the past three decades varied by age group, country income, region, and centre. The high worldwide burden of severe asthma symptoms would be mitigated by enabling access to effective therapies for asthma.

FUNDING

International Union Against Tuberculosis and Lung Disease, Boehringer Ingelheim New Zealand, AstraZeneca Educational Grant, National Institute for Health Research, UK Medical Research Council, European Research Council, and Instituto de Salud Carlos III.

Nutrition, Obesity and Asthma Inception in Children. The Role of Lung Function

Obesity is an important public health problem. WHO estimates that about 39 million children younger than 5 years of age are overweighted or obese. On the other hand, asthma is the most prevalent chronic disease in childhood, and thus, many children share those two conditions. In the present paper we review the epidemiology of children with asthma and obesity, as well as the consequences of being obese on the respiratory system. On the one hand obesity produces an underlying T-helper 2 (TH2) low inflammation state in which numerous cytokines, which could have an impact in the respiratory system play, a role. On the other hand, some respiratory changes have been described in obese children and, specially, the development of the so called “dysanapsis” (the disproportionate scaling of airway dimensions to lung volume) which seems to be common during the first stages of life, probably related to the early development of this condition. Finally, this review deals with the role of adipokines and insulin resistance in the inception and worsening of asthma in the obese child.

Tyrosol improves ovalbumin (OVA)-induced asthma in rat model through prevention of airway inflammation

Asthma is an inflammatory disease that affects many people around the world, especially persons at paediatric age group. The effectiveness of tyrosol, a natural phenolic compound, was examined in the asthma model induced by ovalbumin (OVA). For this purpose, four groups, each consisting of eight rats, were arranged. For 21 days, physiological saline solution was treated to the control group and OVA was treated to the groups of OVA, OVA + dexamethasone (Dexa) and OVA + tyrosol groups, intraperitoneally and through inhalation. Additionally, 0.25 mg/kg Dexa was treated to the OVA + Dexa group and 20 mg/kg tyrosol to the OVA + tyrosol group by oral gavage. Serum, blood, bronchoalveolar lavage fluid (BALF) and lung tissues of the rats were examined. It was observed that MDA level decreased, GSH level and GPx activity increased, and there was no change in CAT activity in lung tissues of the tyrosol treatment groups. It was also observed that NF-κB, TNF-α, IL-4, IL-5, IL-13, IFN-γ and IgE levels decreased compared to the OVA group in lung tissue and serum samples except for serum NF-κB and IL-4. However, no effect on IL-1 β level was observed. In addition, it was determined that tyrosol treatment increased the IL-10 level on both tissue samples. The results of the histopathological investigation of lung tissue showed that tyrosol significantly ameliorated OVA-induced histopathological lesions. Additionally, PAS staining showed that mucus hypersecretion was significantly reduced with the use of tyrosol. In addition, it was determined that the number of eosinophils decreased significantly in blood and BALF samples. The obtained results showed that tyrosol possessed antioxidant and anti-inflammatory features on OVA-induced rats and preserved tissue architecture.

Short-acting β2-agonist prescriptions are associated with poor clinical outcomes of asthma: the multi-country, cross-sectional SABINA III study

Background

To gain a global perspective on short-acting β₂-agonist (SABA) prescriptions and associated asthma-related clinical outcomes in patients with asthma, we assessed primary health data across 24 countries in five continents.

Methods

SABINA III was a cross-sectional study that employed electronic case report forms at a study visit (in primary or specialist care) to record prescribed medication(s), over-the-counter (OTC) SABA purchases and clinical outcomes in asthma patients (≥12 years old) during the past 12 months. In patients with ≥1 SABA prescriptions, associations of SABA with asthma symptom control and severe exacerbations were analysed using multivariable regression models.

Results

Of 8351 patients recruited (n=6872, specialists; n=1440, primary care), 76.5% had moderate-to-severe asthma and 45.4% experienced ≥1 severe exacerbations in the past 12 months. 38% of patients were prescribed ≥3 SABA canisters; 18.0% purchased OTC SABA, of whom 76.8% also received SABA prescriptions. Prescriptions of 3–5, 6–9, 10–12 and ≥13 SABA canisters (versus 1–2) were associated with increasingly lower odds of controlled or partly controlled asthma (adjusted OR 0.64 (95% CI 0.53–0.78), 0.49 (95% CI 0.39–0.61), 0.42 (95% CI 0.34–0.51) and 0.33 (95% CI 0.25–0.45), respectively; n=4597) and higher severe exacerbation rates (adjusted incidence rate ratio 1.40 (95% CI 1.24–1.58), 1.52 (95% CI 1.33–1.74), 1.78 (95% CI 1.57–2.02) and 1.92 (95% CI 1.61–2.29), respectively; n=4612).

Conclusions

This study indicates an association between high SABA prescriptions and poor clinical outcomes across a broad range of countries, healthcare settings and asthma severities, providing support for initiatives to improve asthma morbidity by reducing SABA overreliance.

Findings from SABINA III, which included 8351 patients from 24 countries, indicate that across treatment steps and clinical care settings, high SABA prescriptions were associated with higher rates of severe exacerbations and poorer asthma controlhttps://bit.ly/2VHBISg

Cost-utility of azithromycin in patients with severe asthma

BACKGROUND

An important proportion of asthma patients remain uncontrolled despite the use of inhaled corticosteroids and long-acting beta-agonists. Some add-on therapies, like azithromycin, have been recommended for this subgroup of patients. The purpose of this study was to assess the cost-effectiveness of azithromycin as an add-on therapy to ICS + LABA for patients with severe asthma.

METHODS

A probabilistic Markov model was created to estimate the cost and quality-adjusted life-years (QALYs) of patients with severe asthma in Colombia. The total costs and QALYS of two interventions, including standard therapy (ICS + LABA), and add-on therapy with azithromycin, were calculated over a lifetime horizon. Multiple sensitivity analyses were conducted. Cost-effectiveness was evaluated at a willingness-to-pay value of $19,000.

RESULTS

The model suggests a potential gain of 0.037 QALYs per patient per year on azithromycin, with a difference of US $718 in favor of azithromycin, showing dominance with respect to SOC. A position of dominance negates the need to calculate an incremental cost-effectiveness ratio. In the deterministic sensitivity analyses, our base-case results were robust to variations in all assumptions and parameters.

CONCLUSION

Add-on therapy with azithromycin was found to be cost-effective when added to usual care in patients who remain uncontrolled despite treatment with medium or high-dose ICS/LABA.

Physicians' Knowledge and Practices Regarding Asthma in Jordan: A Cross-Sectional Study

Objectives: Asthma is a chronic non-communicable disease that causes significant morbidity and mortality and requires ongoing clinical care. Appropriate knowledge by physicians is vital in the management of asthma. Therefore, this study aims to explore and identify the gaps in physicians' knowledge and practices concerning the management of asthma.

Methods: A cross-sectional study using an online survey was conducted in Jordan to understand the gap in knowledge and practices in the management of asthma among physicians. A previously validated questionnaire was employed, the Physicians' Practice Assessment Questionnaire (PPAQ). The knowledge questions based on the Global Initiative for Asthma (GINA) guidelines were used to assess knowledge and practice among the study's participants. Predictors of good practice were identified using logistic regression.

Results: A total of 271 physicians participated in this survey. The overall knowledge among physicians scored above 78%. However, gaps were pertinent to identifying the signs of asthma attacks that accounted for 61.9% of the participants, whereas only 67.6% of the physicians knew the drugs used for the management of asthma. The study revealed alarming results when practices were assessed, with the overall percentage of physicians applying the required practices did not exceed 57.1 ± 25.7%. Logistic regression analysis to determine predictors of good practice showed that out of several independent variables, physicians who see 6–10 asthma patients per day are five times more likely to follow the guidelines' recommendations in their practice; senior physicians (>50 years old) and those who see 1–5 asthma patients daily are around two times more likely to follow the guidelines (p 0.001).

Conclusions: The findings of this study identified the need to transform knowledge into practice. This could be achieved through professional education and constant reminders to physicians in a simple form, as well as a clinical audit of practice. There is a need for novel knowledge transfer approaches to induce behavioral and practice change toward the management of asthma.

Protection against allergies: Microbes, immunity, and the farming effect

The prevalence of asthma and other allergic diseases has rapidly increased in "Westernized" countries over recent decades. This rapid increase suggests the involvement of environmental factors, behavioral changes or lifestyle, rather than genetic drift. It has become increasingly clear that the microbiome plays a key role in educating the host immune system and, thus, regulation of disease susceptibility. This review will focus on recent advances uncovering immunological and microbial mechanisms that protect against allergies, in particular, within the context of a farming environment. A whole body of epidemiological data disclosed the nature of the protective exposures in a farm. Current evidence points toward an important role of the host microbiome in setting an immunological equilibrium that determines progression toward, or protection against allergic diseases. Conclusive mechanistic insights on how microbial exposures prevent from developing allergic diseases in humans are still lacking but findings from experimental models reveal plausible immunological mechanisms. Gathering further knowledge on these mechanisms and confirming their relevance in humans is of great importance to develop preventive strategies for children at risk of developing allergies.

Association between Parental Cotinine-verified Smoking Status and Childhood Asthma: a Population-based Nationally Representative Analysis

BACKGROUND

Environmental tobacco smoke exposure due to parents is a modifiable risk factor for childhood asthma, but many studies have evaluated parental smoking using self-reported data. Therefore, we aimed to analyze the relationship between parental cotinine-verified smoking status and asthma in their children.

METHODS

This population-based cross-sectional study used data from the Korean National Health and Nutrition Examination Survey from 2014 to 2017. Participants aged 0 to 18 years with complete self-reported physician-diagnosed childhood asthma and measurement of their parental urinary cotinine levels were included. Parental urinary cotinine-verified smoking status was defined using both urinary cotinine levels and self-report, as active, passive, and non-smoker. Sample weights were applied to all statistical analyses because of a complex, multistage and clustered survey design. Logistic regression model was used to analyze the relationship between childhood asthma and parental smoking.

RESULTS

A total of 5,264 subjects aged < 19 years were included. The prevalence of asthma was 3.4%. The proportions of paternal and maternal urinary cotinine-verified active smokers during the study period were 50.4% and 16.9%, respectively. When parental urinary cotinine level increased, the proportion of parental low household income was increased (P < 0.001). There was no significant association between the parental urinary cotinine-verified smoking group and childhood asthma group. However, the adjusted odds ratios of childhood asthma in the middle and highest tertile of paternal urinary cotinine levels compared with those in lowest tertile were 1.95 (95% confidence interval [CI], 0.98-3.89) and 2.34 (95% CI, 1.21-4.54), respectively.

CONCLUSION

There seems to be a dose-related association between paternal urinary cotinine levels and the risk of childhood asthma. Because of the high rate of paternal smoking, further studies are needed to develop a targeted strategy to reduce parental smoking for childhood asthma.

PM2.5 and water-soluble components induce airway fibrosis through TGF-β1/Smad3 signaling pathway in asthmatic rats

Epidemiological studies have suggested that fine particulate matter (PM_2.5) and asthma have been independently associated with pulmonary fibrosis but rarely studied together. Furthermore, it is unknown whether airway fibrosis in asthma is more attributable to water-soluble ions of PM_2.5. Our current study was to explore the potential mechanism of PM_2.5 and water-soluble components on airway fibrosis in ovalbumin (OVA)-sensitized asthmatic rats. Rats were intratracheally instilled with PM_2.5 and water-soluble components every 3 days for 4 times or 8 times. Histopathological examination demonstrated that lung inflammatory and airway fibrosis were induced after PM_2.5 and water-soluble components exposure. Meanwhile, PM_2.5, in particular water-soluble extracts, increased expression of collagen 1 (COL-1), connective tissue growth factor (CTGF), interleukin-6 (IL-6), transforming growth factor-β1 (TGF-β1), Smad family member 3 (Smad3), and p-Smad3, whereas decreased secretion of heme oxygenase-1 (HO-1). However, pretreating asthmatic rats with SB432542, the inhibitor of TGF-β1, and SIS3 HCl, the antagonist of Smad3, both reversed the activation of airway fibrosis induced by water-soluble extracts. Therefore, TGF-β1/Smad3 signaling pathway may be responsible for the pathological process of airway fibrosis in asthmatic rats following PM_2.5 and water-soluble components exposure.

Psychological burden of asthma in adolescents and their parents

INTRODUCTION

Asthma, a common chronic disease in adolescents is impacted by factors affecting quality of life. This study aimed to determine the psychosocial factors of adolescents with asthma and their parents.

METHODS

The study included 122 adolescents with asthma, 82 healthy controls, and their parents who completed the Asthma Control Test (ACT), Pediatric Asthma Quality of Life Questionnaire (PAQLQ) and the Brief Symptom Inventory (BSI).

RESULTS

The mean age was 14.2 ± 1.9 years. ACT score was high and depression was low in patients with good treatment compliance. As the age of the first asthma symptoms/diagnosis increased, somatization, anxiety, hostility and general psychopathology scores increased, as did the somatization score of parents. Parental anxiety score was not related with adolescent BSI scores in the controls but in the study group when it was higher, the anxiety, depression, somatization, and general psychopathology scores were higher. PAQLQ showed that anxiety, negative self-esteem, somatization, depression, and general psychopathology were higher in patients concerned about asthma. Depression and somatization scores were higher in the parents of patients who perceived that "Treatment does not contribute to asthma control." Somatization scores were higher among parents of patients who noted: "Asthma will not pass in the long-term" and "I cannot control asthma."

CONCLUSION

Higher scores of asthma patients who were anxious about the disease and families who were despondent about treatment demonstrate that health care providers should spend more time informing patients and caregivers. Increasing patient treatment compliance during early adolescence will lessen the psychological burden of the disease.

A comparison of efficacy and safety of complementary and alternative therapies for children with asthma: A protocol for systematic review and meta analysis

BACKGROUND

Bronchial Asthma is a chronic, hyperreactive inflammation of the airway that involves a variety of inflammatory cells. Due to the persistence of airway hyperresponsiveness, lung function is progressively damaged, making asthma more stubborn and difficult to heal. In recent years, the prevalence of childhood asthma is still on an increasing trend. Repeated asthma attacks not only affect children's life and learning, but also bring greater economic and mental burden to children's families, and even threaten children's lives. Traditional treatment methods such as oral western medicine, atomization therapy has obvious limitations, and the complementary and alternative therapy is an effective method to treat asthma in children. This study will evaluate the efficacy and safety of various complementary and alternative therapies for children with asthma by means of mesh meta-analysis. In order to provide the basis for clinical rational use.

METHODS

Use the computer to search the self-built database until January 2021, the China National Knowledge Infrastructure, Wanfang Database, Chinese Scientific Journals Database, China Biomedical Literature Database, PubMed, Cochrance Library, EMBASE, Web of Science, Clinical Trials and other electronic databases to collect RCT studies on complementary and alternative therapies for for children with asthma. We will screen the relevant literature included in the systematic review/meta analysis. At the same time, Revman 5.3 software will be used for meta-analysis, and grade will be used to grade the quality of evidence in the network meta-analysis.

RESULTS

This study will compare the efficacy and safety of different complementary and alternative therapies to treat childhood asthma, and evaluate and rank different interventions.

CONCLUSION

The combined use of complementary and alternative therapies for childhood asthma on the basis of conventional basic treatment can improve clinical efficacy, reduce the occurrence of adverse reactions, improve the quality of life of children, and provide strong support for the rational use of clinicians.

INPLASY REGISTRATION NUMBER

INPLASY202120005.

Global Asthma Network Phase I Surveillance: Geographical Coverage and Response Rates

Background—The Global Asthma Network (GAN) Phase I is surveying school pupils in high-income and low- or middle-income countries using the International Study of Asthma and Allergies in Childhood (ISAAC) methodology. Methods—Cross-sectional surveys of participants in two age groups in randomly selected schools within each centre (2015–2020). The compulsory age group is 13–14 years (adolescents), optionally including parents or guardians. Six to seven years (children) and their parents are also optional. Adolescents completed questionnaires at school, and took home adult questionnaires for parent/guardian completion. Children took home questionnaires for parent/guardian completion about the child and also adult questionnaires. Questions related to symptoms and risk factors for asthma and allergy, asthma management, school/work absence and hospitalisation. Results—53 centres in 20 countries completed quality checks by 31 May 2020. These included 21 centres that previously participated in ISAAC. There were 132,748 adolescents (average response rate 88.8%), 91,802 children (average response rate 79.1%), and 177,622 adults, with >97% answering risk factor questions and >98% answering questions on asthma management, school/work absence and hospitalisation. Conclusion—The high response rates achieved in ISAAC have generally been maintained in GAN. GAN Phase I surveys, partially overlapping with ISAAC centres, will allow within-centre analyses of time-trends in prevalence.