Expression of LINC00847 in Peripheral Blood Mononuclear Cells of Children with Asthma and Its Prediction between Asthma Exacerbation and Remission

Objective. Asthma is defined as a heterogeneous disease that is usually characterized by chronic airway inflammation. Long noncoding RNAs play important roles in various biological processes including inflammation. To know more about the relationships between lncRNAs and asthma, we sought to the role of LINC00847 in peripheral blood mononuclear cells (PBMCs) of children with asthma exacerbation or asthma remission. Methods. Microarray analysis was performed on GSE143192 and GSE165934 datasets to screen differentially expressed lncRNAs (DElncRNAs) in human PBMCs between asthma patients and normal controls. LINC00847 was selected from DElncRNAs in human PBMCs between asthma patients and normal controls for further investigation. The expression levels of LINC00847 were quantified in PBMCs collected from 54 children with asthma exacerbation, 54 children with asthma remission, and 54 healthy children by real-time qPCR. The forced expiratory volume in the first second in percent predicted values (FEV1%), ratio of forced expiratory volume in 1 second to forced vital capacity (FEV1/FVC), and peak expiratory flow rate (PEF%) were tested for evaluation of lung function. The concentration of immunoglobulin E (IgE) and eosinophil count was examined. The serum levels of interleukin-4 (IL-4), interferon-γ (IFN-γ), and IL-17A were determined by the ELISA method. Results. The expression level of LINC00847 in PBMCs of asthma exacerbation children was remarkably higher than that in PBMCs of asthma remission children and healthy children ( $p<0.001$ ); the expression level of LINC00847 in PBMCs of asthma remission children was notably higher than that in PBMCs of healthy children ( $p<0.001$ ). Pearson correlation analysis revealed that the expression levels of LINC00847 in PBMCs of asthma children were negatively correlated with FEV1% (r = −0.489), FEV1/FVC (r = −0.436), PEF% (r = −0.626), and IFN-γ level (r = −0.614) of asthma children, but positively correlated with IgE concentration (r = 0.680), eosinophil count (r = 0.780), IL-4 (r = 0.524), and IL-17A (r = 0.622) levels. When LINC00847 expression was used to distinguish asthma exacerbation from asthma remission, a 0.871 AUC (95% CI: 0.805–0.936) was yielded with sensitivity of 79.63% and specificity of 77.78%. Conclusion. The study demonstrates that increased LINC00847 expression may be associated with the development and progression of asthma, possibly serving as a novel biomarker for predicting asthma exacerbation from asthma remission.

Does machine learning have a role in the prediction of asthma in children?

Asthma is the most common chronic lung disease in childhood. There has been a significant worldwide effort to develop tools/methods to identify children's risk for asthma as early as possible for preventative and early management strategies. Unfortunately, most childhood asthma prediction tools using conventional statistical models have modest accuracy, sensitivity, and positive predictive value. Machine learning is an approach that may improve on conventional models by finding patterns and trends from large and complex datasets. Thus far, few studies have utilized machine learning to predict asthma in children. This review aims to critically assess these studies, describe their limitations, and discuss future directions to move from proof-of-concept to clinical application.

Paediatric hospitalisations due to COVID-19 during the first SARS-CoV-2 omicron (B.1.1.529) variant wave in South Africa: a multicentre observational study

Background

South Africa reported a notable increase in COVID-19 cases from mid-November, 2021, onwards, starting in Tshwane District, which coincided with the rapid community spread of the SARS-CoV-2 omicron (B.1.1.529) variant. This increased infection rate coincided with a rapid increase in paediatric COVID-19-associated admissions to hospital (hereafter referred to as hospitalisations).

Methods

The Tshwane Maternal-Child COVID-19 study is a multicentre observational study in which we investigated the clinical manifestations and outcomes of paediatric patients (aged ≤19 years) who had tested positive for SARS-CoV-2 and were admitted to hospital for any reason in Tshwane District during a 6-week period at the beginning of the fourth wave of the COVID-19 epidemic in South Africa. We used five data sources, which were: (1) COVID-19 line lists; (2) collated SARS-CoV-2 testing data; (3) SARS-CoV-2 genomic sequencing data; (4) COVID-19 hospitalisation surveillance; and (5) clinical data of public sector COVID-19-associated hospitalisations among children aged 13 years and younger.

Findings

Between Oct 31 and Dec 11, 2021, 6287 children and adolescents in Tshwane District were recorded as having COVID-19. During this period, 2550 people with COVID-19 were hospitalised, of whom 462 (18%) were aged 19 years or younger. The number of paediatric cases was higher than in the three previous SARS-CoV-2 waves, uncharacteristically increasing ahead of adult hospitalisations. 75 viral samples from adults and children in the district were sequenced, of which 74 (99%) were of the omicron variant. Detailed clinical notes were available for 138 (75%) of 183 children aged ≤13 years with COVID-19 who were hospitalised. 87 (63%) of 138 children were aged 0–4 years. In 61 (44%) of 138 cases COVID-19 was the primary diagnosis, among whom symptoms included fever (37 [61%] of 61), cough (35 [57%]), shortness of breath (19 [31%]), seizures (19 [31%]), vomiting (16 [26%]), and diarrhoea (15 [25%]). Median length of hospital stay was 2 days [IQR 1–3]). 122 (88%) of 138 children with available data needed standard ward care and 27 (20%) needed oxygen therapy. Seven (5%) of 138 children were ventilated and four (3%) died during the study period, all related to complex underlying copathologies. All children and 77 (92%) of 84 parents or guardians with available data were unvaccinated to COVID-19.

Interpretation

Rapid increases in paediatric COVID-19 cases and hospitalisations mirror high community transmission of the SARS-CoV-2 omicron variant in Tshwane District, South Africa. Continued monitoring is needed to understand the long-term effect of the omicron variant on children and adolescents.

Funding

South African Medical Research Council, South African Department of Science & Innovation, G7 Global Health Fund.

Evaluating Children and Adolescents with Suspected Exercise Induced Asthma: Real Life Data

OBJECTIVE

Exercise-induced bronchoconstriction (EIB) occurs frequently in children and adolescents and may be a sign of insufficient asthma control. EIB is often evaluated by respiratory symptoms, spirometry, eNO measurement and methacholine testing (MCT) instead of time consuming exercise test. Aim of this study was to analyse the amount of patients for which an exercise challenge in a cold chamber (ECC) was needed for a clear EIB diagnosis, to characterize EIB phenotypes and the incidence of exercise induced laryngeal obstruction (EILO) in a large cohort of patients with EIB.

METHODS

A retrospective analysis was performed in 595 children and adolescents (mean age 12.1 years) with suspected EIB from January 2014 to December 2018. Complete data sets of skin prick test, spirometry, eNO and MCT were available from 336 patients.

RESULTS

An ECC to confirm the EIB diagnosis was performed in 125 (37.2%) of patients. Three EIB phenotypes were detected: group 1: EIB without allergic sensitization (n=159); group 2: EIB with other than house dust mite (HDM) sensitization (n=87) and group 3: EIB with HDM sensitization (n=90). MCT and eNO showed significant differences between the subgroups: An eNO>46 ppb and/or a MCT<0.1 mg was found in 23.9% vs. 50.6% vs. 57.8% in group 1-3, respectively. Significantly more patients suffered from EILO in group 1 compared to group 2 and 3 (n=13 vs. n=1).

CONCLUSION

EIB without sensitization is as often as EIB with sensitization. In patients without sensitization, EILO has to be considered as a possible cause of symptoms during exercise.

Late Pre-term Infants with Severe Bronchiolitis and Risk of Asthma by Age 5 Years

In a prospective, multicenter cohort of infants hospitalized with bronchiolitis, we found infants born late pre-term (ie, gestational age of 34-36.9 weeks) had 35% higher odds of having asthma by age 5 years compared with infants born at full-term.

A multicenter retrospective study of clinical features, laboratory characteristics, and outcomes of 166 hospitalized children with coronavirus disease 2019 (COVID-19): A preliminary report from Iranian Network for Research in Viral Diseases (INRVD)

BACKGROUND

The objectives of this study were to analyze the clinical features and laboratory profiles and risk factors associated with critical illness of children with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

METHODS

One hundred and sixty-six coronavirus disease 2019 (COVID-19) Iranian pediatric patients were recruited through a collaborative research network between March and May 2020. Demographics, clinical, laboratory, and radiological results were obtained from patient files.

RESULTS

Of 166 patients, 102 (61%) and 64 (39%) were males and females, respectively. Ninety-six (57.8%) and 70 (42.2%), had moderate and severe conditions, respectively. Thirty (18%) of patients died. The common symptoms were fever (73%), cough (54%), and shortness of breath, headache decrease in neutrophil and platelet counts; increase values in lactate dehydrogenase, decrease in the blood pH and HCO3 were significantly associated with the disease severity. 54% and 56% of patients showed abnormal radiographic appearance in Chest X-ray and in chest computed tomography scan, respectively. Sixty-one (36.7%) of patients were referred to intensive care unit (ICU). The coexistence of comorbidity was the main factor associated with ICU admission, shock, arrhythmia, acute kidney injury, acute respiratory distress syndrome, acute cardiac injury, and death.

CONCLUSIONS

We describe a higher than previously recognized rate of COVID-19 mortality in Iranian pediatric patients. Epidemiological factors, such as the relatively high case fatality rate in the country and the presence of underlying diseases were the main factors for the high death rate.

Difficult-to-Treat Asthma Management in School-Age Children

The World Health Organization divides severe asthma into three categories: untreated severe asthma; difficult-to-treat severe asthma; and severe, therapy-resistant asthma. The apparent frequency of severe asthma in the general population of asthmatic children is probably around 5%. Upon referral of these children, it is important to evaluate the diagnosis of asthma carefully before modifying management and applying a long-term monitoring plan. Identification of pathophysiologic phenotypes using objective biomarkers is essential in our routine assessments of severe asthma. Although conventional pharmacologic approaches should be attempted first, there is growing recognition that children with difficult-to-treat asthma may have unique clinical phenotypes that may necessitate alternative treatment approaches including asthma biologics. These new medications, especially those with effects on multiple pathologic features of asthma, raise the hope that new treatment strategies could induce remission. Besides introducing new medications, the opportunity for closer monitoring is feasible with advances in digital health. Therefore, we have the opportunity to improve response to medications, individualize treatment, and monitor response along with potential steps to prevent severe asthma.

Severe pediatric asthma with a poor response to omalizumab: a report of three cases and three-dimensional bronchial wall analysis

Omalizumab is used for the treatment of persistent severe allergic asthma in adults and children. However, some patients remain symptomatic even after omalizumab treatment. In bronchial asthma, chronic inflammation of the bronchial wall causes thickening of the airway wall, resulting from irreversible airway remodeling. Progression of airway remodeling causes airflow obstruction, leading to treatment resistance. We report three Japanese children with severe asthma who had a poor response to omalizumab treatment. They had a long period of inadequate management of asthma before initiating omalizumab. Even after omalizumab treatment, their symptoms persisted, and the parameters of spirometry tests did not improve. We hypothesized that omalizumab was less effective in these patients because airway wall remodeling had already progressed. We retrospectively evaluated the bronchial wall thickness using a three-dimensional bronchial wall analysis with chest computed tomography. The bronchial wall thickness was increased in these cases compared with six responders. Progressed airway wall thickness caused by airway remodeling may be associated with a poor response to omalizumab in children with severe asthma.

High Infection Secondary Attack Rates of Severe Acute Respiratory Syndrome Coronavirus 2 in Dutch Households Revealed by Dense Sampling

BACKGROUND

Indoor environments are considered one of the main settings for transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Households in particular represent a close-contact environment with high probability of transmission between persons of different ages and roles in society.

METHODS

Households with a laboratory-confirmed SARS-CoV-2 positive case in the Netherlands (March-May 2020) were included. At least 3 home visits were performed during 4-6 weeks of follow-up, collecting naso- and oropharyngeal swabs, oral fluid, feces and blood samples from all household members for molecular and serological analyses. Symptoms were recorded from 2 weeks before the first visit through to the final visit. Infection secondary attack rates (SAR) were estimated with logistic regression. A transmission model was used to assess household transmission routes.

RESULTS

A total of 55 households with 187 household contacts were included. In 17 households no transmission took place; in 11 households all persons were infected. Estimated infection SARs were high, ranging from 35% (95% confidence interval [CI], 24%-46%) in children to 51% (95% CI, 39%-63%) in adults. Estimated transmission rates in the household were high, with reduced susceptibility of children compared with adolescents and adults (0.67; 95% CI, .40-1.1).

CONCLUSION

Estimated infection SARs were higher than reported in earlier household studies, presumably owing to our dense sampling protocol. Children were shown to be less susceptible than adults, but the estimated infection SAR in children was still high. Our results reinforce the role of households as one of the main multipliers of SARS-CoV-2 infection in the population.

Severe Pediatric Asthma Therapy: Mepolizumab

There is a growing need for advanced treatment in children with persistent and severe asthma symptoms. As a matter of fact, between 2 and 5% of asthmatic children experience repeated hospitalizations and poor quality of life despite optimized treatment with inhaled glucocorticoid plus a second controller. In this scenario, mepolizumab, a humanized monoclonal antibody, has proven to be effective in controlling eosinophil proliferation by targeting interleukin-5 (IL-5), a key mediator of eosinophil activation pathways. Mepolizumab is approved since 2015 for adults at a monthly dose of 100 mg subcutaneously and it has been approved for patients ≥ 6 years of age in 2019. Especially in children aged 6 to 11 years, mepolizumab showed a greater bioavailability, with comparable pharmacodynamics parameters as in the adult population. The recommended dose of 40 mg every 4 weeks for children aged 6 through 11 years, and 100 mg for patients ≥ 12 years provides appropriate concentration and proved similar therapeutic effects as in the adult study group. A marked reduction in eosinophil counts clinically reflects a significant improvement in asthma control as demonstrated by validated questionnaires, reduction of exacerbation rates, and the number of hospitalizations. Finally, mepolizumab provides a safety and tolerability profile similar to that observed in adults with adverse events mostly of mild or moderate severity. The most common adverse events were headache and injection-site reaction. In conclusion, mepolizumab can be considered a safe and targeted step-up therapy for severe asthma with an eosinophilic phenotype in children and adolescents.

Lung clearance index predicts persistence of preschool wheeze

BACKGROUND

The lung clearance index (LCI) is a measure of pulmonary function. Variable feasibility (50->80%) in preschool children has been reported. There are limited studies exploring its relationship to respiratory symptoms and how it predicts persistent wheeze. We aimed to assess the association with respiratory symptoms in preschool-aged children with LCI and determine its utility in predicting persistent wheeze.

METHODS

LCI was measured in a subcohort of the CHILD Cohort Study at age 3 years using SF₆  multiple breath washout test mass spectrometry. Respiratory symptom phenotypes at age 3 were derived from children's respiratory symptoms reported by their parents. Responses were used to categorize children into 4 symptom groups: recurrent wheeze (3RW), recurrent cough (3RC), infrequent symptoms (IS), and no current symptoms (NCS). At age 5 years, these children were seen by a specialist clinician and assessed for persistent wheeze (PW).

RESULTS

At age 3 years, 69% (234/340) had feasible LCI. Excluding two children with missing data, 232 participants were categorized as follows: 33 (14%) 3RW; 28 (12%) 3RC; 17 (7%) IS; and 154 (66%) NCS. LCI z-score at age 3 years was highest in children with 3RW compared to 3RC (mean (SD): 1.14 (1.56) vs. 0.09 (0.95), p < .01), IS (mean (SD): -0.14 (0.59), p < .01), and NCS (mean (SD): -0.08 (1.06), p < .01). LCI z-score at age 3 was predictive of persistent wheeze at age 5 (PW) (AUROC: 0.87).

CONCLUSIONS

LCI at age 3 was strongly associated with recurrent wheeze at age 3, and predictive of its persistence to age 5.

The relationship of domestic pet ownership with the risk of childhood asthma: A systematic review and meta-analysis

BACKGROUND AND OBJECTIVE

The relationship between pet ownership and childhood asthma remains controversial. In recent years, there have been increasing studies with large sample size. Therefore, we conducted this systematic review and meta-analysis to evaluate the relationship between pet ownership and childhood asthma.

METHOD

Relevant research was retrieved from PubMed, Cochrane, EMBASE, and Web of science. The retrieval was as of October 1, 2021. The Newcastle-Ottawa Scale (NOS) was used to assess the quality of the included studies. Stata 15.0 was used to conduct the meta-analysis.

RESULTS

A total of 60 studies with large sample size published between 1995 and 2021 were included in this systematic review and meta-analysis, which included 18 cohort studies and 42 case-control studies covering 27 countries and 1,871,295 children. As shown by meta-analysis results, cat ownership (OR = 1.18, 95%CI: 1.05∼1.33) and dog ownership (OR = 1.12, 95%CI: 1.0 0∼1.24) have a significant bearing on the occurrence of childhood asthma. Pet ownership was also positively correlated with the occurrence of severe childhood asthma (OR = 1.15, 95%CI: 1.11∼1.20).

CONCLUSION

Pet ownership, especially cats and dogs, is associated with the occurrence of asthma in children.

Early Bronchiolitis Contributes to Preschool Asthma

This study aims to analyze whether bronchiolitis in children younger than one-year-old contributes to subsequent asthma. Medical data were retrieved from the National Health Insurance Research Database of Taiwan. Participants were divided into study (N = 65,559) and control (N = 49,656) groups, depending on whether they had early bronchiolitis. Incidences of asthma, potential comorbidities, and associated medical conditions were compared. The incidence of childhood asthma was significantly higher in the study group (aHR = 1.127, 95% CI: 1.063-1.195). Children with bronchiolitis hospitalization displayed higher asthma risk in the period between two and four years of age. The risk diminished as the children grew up. No relevant synergistic effects were found between bronchiolitis and atopic dermatitis. In conclusion, bronchiolitis before one year of age exhibits predictive value for development of preschool asthma, especially in children with bronchiolitis hospitalizations.

Focus on Early COPD: Definition and Early Lung Development

Chronic obstructive pulmonary disease (COPD) is a disease with high incidence rate and mortality rates worldwide. It is the third leading cause of death in the world. Nevertheless, little progress has been made in treating and preventing the disease. Under these circumstances, the concept of “early COPD” was proposed. Although this concept is not new, most health-care workers do not fully understand early COPD and tend to confuse it with mild COPD. In this review, we mainly discuss the definition of early COPD and the developmental trajectory of lung function. Although patients with early COPD have no symptoms, their lung function is already lower than that of normal people. A relatively complete definition is needed to identify this group of people. Reduced lung function is the diagnostic criterion for COPD, but lung development is a long-term dynamic process. In addition to smoking and air pollution, we should pay more attention to prenatal and childhood risk factors, for example, parents smoking, birth weight, preterm birth, mode of delivery, childhood respiratory infections and childhood asthma. Health-care workers need to be fully aware of early COPD, to reduce the morbidity of COPD and take effective measures to prevent these risk factors.

Impact of early life exposures on respiratory disease

The antecedents of asthma and chronic obstructive pulmonary disease (COPD) lie before school age. Adverse effects are transgenerational, antenatal and in the preschool years. Antenatal adverse effects impair spirometry by causing low birth weight, altered lung structure and immune function, and sensitizing the foetus to later insults. The key stages of normal lung health are lung function at birth, lung growth to a plateau age 20-25 years, and the phase of decline thereafter; contrary to perceived wisdom, accelerated decline is not related to smoking. There are different trajectories of lung function. Lung function usually tracks from preschool to late middle age. Asthma is driven by antenatal and early life influences. The airflow obstruction, emphysema and multi-morbidity of COPD all start early. Failure to reach a normal plateau and accelerated decline in lung function are risk factors for COPD. Airway disease cannot be prevented in adult life; prevention must start early.

Impact of prenatal and early life environmental exposures on normal human development

The global burden and pattern of disease has changed in recent decades, with fewer early childhood deaths and longer lives complicated by chronic disease. Disruption of normal human growth and development by adverse environmental exposures, especially during foetal development and early postnatal life increase life-long risk of chronic disease. The developmental timing and method of adverse exposure determines the likely impact on health and development. While many organ systems are structurally and functionally mature at birth, the CNS, respiratory and immune systems are not and undergo prolonged periods of postnatal growth and development. As such, these organ systems are vulnerable to adverse effects of both prenatal and postnatal environmental exposures. While the precise mechanisms underlying chronic disease are unknown, epigenetic mechanisms and the induction of oxidative stress are likely to be involved. An understanding of these processes is necessary to develop mitigation strategies aimed at reducing chronic disease prevalence.

Wheezing in preterm infants and children

Wheezing is a common outcome of preterm birth. This article will review the mechanisms, epidemiology, and treatment of wheezing in preterm children with and without a history of bronchopulmonary dysplasia.

Autoinflammatory Diseases and Cytokine Storms-Imbalances of Innate and Adaptative Immunity

Innate and adaptive immune responses have a well-known link and represent the distinctive origins of several diseases, many of which may be the consequence of the loss of balance between these two responses. Indeed, autoinflammation and autoimmunity represent the two extremes of a continuous spectrum of pathologic conditions with numerous overlaps in different pathologies. A common characteristic of these dysregulations is represented by hyperinflammation, which is an exaggerated response of the immune system, especially involving white blood cells, macrophages, and inflammasome activation with the hyperproduction of cytokines in response to various triggering stimuli. Moreover, hyperinflammation is of great interest, as it is one of the main manifestations of COVID-19 infection, and the cytokine storm and its most important components are the targets of the pharmacological treatments used to combat COVID-19 damage. In this context, the purpose of our review is to provide a focus on the pathogenesis of autoinflammation and, in particular, of hyperinflammation in order to generate insights for the identification of new therapeutic targets and strategies.

Delineating phenotypes of Kawasaki disease and SARS-CoV-2-related inflammatory multisystem syndrome: a French study and literature review

Objective

To better define the clinical distinctions between the new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-related paediatric inflammatory multisystem syndrome (PIMS) and Kawasaki disease (KD).

Methods

We compared three groups of patients: group 1, cases from our national historic KD database (KD-HIS), before the SARS-CoV-2 pandemic; group 2, patients with KD admitted to an intensive care unit (KD-ICU) from both our original cohort and the literature, before the SARS-CoV-2 pandemic; and group 3, patients with PIMS from the literature.

Results

KD-HIS included 425 patients [male:female ratio 1.3, mean age 2.8 years (s.d. 2.4)], KD-ICU 176 patients [male:female ratio 1.3, mean age 3.5 years (s.d. 3.1)] and PIMS 404 patients [male:female ratio 1.4, mean age 8.8 years (s.d. 3.7)]. As compared with KD-HIS patients, KD-ICU and PIMS patients had a higher proportion of cardiac failure, digestive and neurological signs. KD-ICU and PIMS patients also had a lower frequency of typical KD-mucocutaneous signs, lower platelet count, higher CRP and lower sodium level. As compared with KD-HIS and KD-ICU patients, PIMS patients were older and more frequently had myocarditis; they also had fewer coronary abnormalities and lower sodium levels. Unresponsiveness to IVIG was more frequent in KD-ICU than KD-HIS and PIMS patients.

Conclusion

On clinical grounds, KD-HIS, KD-ICU and PIMS might belong to a common spectrum of non-specific pathogen-triggered hyperinflammatory states. The causes of increasing inflammation severity within the three entities and the different effects on the heart remain to be determined.

The predictive role of small airway dysfunction and airway inflammation biomarkers for asthma in preschool and school-age children: a study protocol for a prospective cohort study

BACKGROUND

Preschool children are at a high risk of developing asthma. Asthma in preschool children could remit in most cases, but could persist into school age, adolescence, or even adulthood in some cases. However, it is difficult to predict which children with preschool asthma will develop into school-age asthma. We present a cohort study protocol to explore the predictive role of small airway dysfunction and airway inflammation biomarkers of asthma in preschool and school-age children.

METHODS

A prospective cohort study will be conducted with at least 205 children with preschool asthma. All patients will be recruited when they consult a pediatric pulmonologist at the Children's Hospital of Chongqing Medical University and will be followed up to 6 years of age. Initially, patients' demographic information, medical history, physical findings, and questionnaire information will be collected, and baseline small airway function and inflammation biomarkers will be detected. During the follow-up period, medical history, physical findings, and the questionnaire results will be collected every 3 months, and small airway function will be tested by impulse oscillometry (IOS) every 6 months. At the final visit, a definite diagnosis of school-age asthma will be made by a pediatric pulmonologist based on the criteria of the Global Initiative for Asthma 2020.

DISCUSSION

The study will be the first to be conducted in preschool children assessing whether small airway dysfunction combined with airway eosinophilic biomarkers and club cell secretory protein is associated with school-age asthma. This study may provide new promising predictors of persistent asthma from preschool to school age.

TRIAL REGISTRATION

The study has been registered at the Chinese Clinical Trial Registry (ChiCTR2000039583). Registered on November 1, 2020. Protocol version: version 1.0, August 16, 2021.

Influence of Childhood Exposure to a Farming Environment on Age at Asthma Diagnosis in a Population-Based Study

Purpose

Asthma is a heterogeneous disease, and factors associated with different asthma phenotypes are poorly understood. Given the higher prevalence of farming exposure and late diagnosis of asthma in more rural Western Finland as compared with the capital of Helsinki, we investigated the relationship between childhood farming environment and age at asthma diagnosis.

Methods

A cross-sectional population-based study was carried out with subjects aged 20–69 years in Western Finland. The response rate was 52.5%. We included 3864 participants, 416 of whom had physician-diagnosed asthma at a known age and with data on the childhood environment. The main finding was confirmed in a similar sample from Helsinki. Participants were classified as follows with respect to asthma diagnosis: early diagnosis (0–11 years), intermediate diagnosis (12–39 years), and late diagnosis (40–69 years).

Results

The prevalence of asthma was similar both without and with childhood exposure to a farming environment (11.7% vs 11.3%). Allergic rhinitis, family history of asthma, ex-smoker, occupational exposure, and BMI ≥ 30 kg/m² were associated with a higher likelihood of asthma. Childhood exposure to a farming environment did not increase the odds of having asthma (aOR, 1.10; 95% CI, 0.87–1.40). It did increase the odds of late diagnosis (aOR, 2.30; 95% CI, 1.12–4.69), but the odds were lower for early (aOR, 0.49; 95% CI, 0.30–0.80) and intermediate diagnosis of asthma (aOR, 0.75; 95% CI, 0.47–1.18).

Conclusion

Odds were lower for early diagnosis of asthma and higher for late diagnosis of asthma in a childhood farming environment. This suggests a new hypothesis concerning the etiology of asthma when it is diagnosed late.

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Allergy-related diseases in childhood and risk for abdominal pain-related functional gastrointestinal disorders at 16 years-a birth cohort study

BACKGROUND

Studies on allergy-related diseases in relation to abdominal pain-related functional gastrointestinal disorders (AP-FGIDs) in children are few and results are contradictory. We examined the associations between childhood allergy-related diseases and adolescent AP-FGIDs in general and irritable bowel syndrome (IBS) in particular.

METHOD

Prospective population-based birth cohort study of 4089 children born in Sweden 1994-1996. We analysed data from 2949 children with complete follow-up at 16 years (y) and no diagnosis of inflammatory bowel disease or coeliac disease at 12y or 16y. Asthma, rhinitis, eczema, and food hypersensitivity (FH) were assessed through questionnaires at 1-2y, 4y, 8y, 12y, and 16y. AP-FGIDs and IBS were assessed through questionnaires at 16y and defined according to the Rome III criteria. Associations between childhood allergy-related diseases and any AP-FGID and IBS and 16y respectively were examined using binomial generalized linear models with a log link function and described as relative risk with 95% confidence intervals.

RESULTS

The prevalence of any AP-FGID and IBS at 16y were 12.0% and 6.0% respectively. Eczema at 1-2y, 4y, and 8y, and FH at 12y and 16y were associated with an increased risk for any AP-FGID at 16y. Asthma and FH at 12y and 16y were associated with an increased risk for IBS at 16y. The relative risk for IBS at 16y increased with increasing number of concurrent allergy-related diseases at 16y, but linear trend for relative risk was only borderline statistically significant (P for trend = 0.05).

CONCLUSIONS

This prospective population-based study demonstrated positive associations between childhood allergy-related diseases and adolescent AP-FGIDs, including IBS, implicating shared pathophysiology among these disorders.

Airway Sensory Nerve Plasticity in Asthma and Chronic Cough

Airway sensory nerves detect a wide variety of chemical and mechanical stimuli, and relay signals to circuits within the brainstem that regulate breathing, cough, and bronchoconstriction. Recent advances in histological methods, single cell PCR analysis and transgenic mouse models have illuminated a remarkable degree of sensory nerve heterogeneity and have enabled an unprecedented ability to test the functional role of specific neuronal populations in healthy and diseased lungs. This review focuses on how neuronal plasticity contributes to development of two of the most common airway diseases, asthma and chronic cough, and discusses the therapeutic implications of emerging treatments that target airway sensory nerves.

Hypertensive disorders in pregnancy and risk of asthma in offspring: a systematic review and meta-analysis

OBJECTIVES

The association between hypertensive disorders in pregnancy (HDP) and an increased risk of asthma in offspring remains controversial. No systematic review of this topic has been performed. The aim of this systematic review was to summarise the available evidence regarding the association between HDP and the risk of asthma in offspring.

DESIGN

Systematic review and meta-analysis.

METHODS

On the basis of a prepared protocol, a systematic search of PubMed, EMBASE, the Cochrane Library and Web of Science was performed using a detailed search strategy from the database inception to 17 January 2020. Cohort, case-control and cross-sectional studies published in English reporting the diagnoses of maternal HDP and asthma in offspring were included. The Meta-analysis of Observational Studies in Epidemiology guidelines were followed throughout the study. The estimated pooled ORs of HDP and asthma in offspring were calculated from the studies, and the meta-analysis was performed using random-effects models.

RESULTS

Ten cohort studies involving a total of 6 270 430 participants were included. According to the Newcastle-Ottawa Scale, the overall methodological quality was good since 8 studies were of high quality and 2 studies were of moderate quality. After controlling for potential confounders, HDP was associated with a possible increased risk of asthma in offspring, with a pooled adjusted OR (aOR) of 1.19 (95% CI 1.12 to 1.26). The subgroup analyses according to HDP subgroups, sibling design, study quality, study location, offspring ages, singleton status, exposure assessment, outcome assessment and adjusted factors showed similar results.

CONCLUSIONS

Exposure to HDP may be associated with an increased risk of asthma in offspring. Further research is needed to verify the results and determine whether the observed relationship is causal.

PROSPERO REGISTRATION NUMBER

CRD42020148250.

Biologicals in childhood severe asthma: the European PERMEABLE survey on the status quo

Introduction

Severe asthma is a rare disease in children, for which three biologicals, anti-immunoglobulin E, anti-interleukin-5 and anti-IL4RA antibodies, are available in European countries. While global guidelines exist on who should receive biologicals, knowledge is lacking on how those guidelines are implemented in real life and which unmet needs exist in the field. In this survey, we aimed to investigate the status quo and identify open questions in biological therapy of childhood asthma across Europe.

Methods

Structured interviews regarding experience with biologicals, regulations on access to the different treatment options, drug selection, therapy success and discontinuation of therapy were performed. Content analysis was used to analyse data.

Results

We interviewed 37 experts from 25 European countries and Turkey and found a considerable range in the number of children treated with biologicals per centre. All participating countries provide public access to at least one biological. Most countries allow different medical disciplines to prescribe biologicals to children with asthma, and only a few restrict therapy to specialised centres. We observed significant variation in the time point at which treatment success is assessed, in therapy duration and in the success rate of discontinuation. Most participating centres intend to apply a personalised medicine approach in the future to match patients a priori to available biologicals.

Conclusion

Substantial differences exist in the management of childhood severe asthma across Europe, and the need for further studies on biomarkers supporting selection of biologicals, on criteria to assess therapy response and on how/when to end therapy in stable patients is evident.

This study reveals enormous differences in therapy with biologicals for childhood severe asthma across Europe, and demonstrates the urgent need for harmonisation in medication choice, definition of therapy success and how/when to discontinue treatmenthttps://bit.ly/3tnJMTY

Changes in Pediatric ICU Utilization and Clinical Trends During the Coronavirus Pandemic

BACKGROUND

Children have been less affected by the COVID-19 pandemic, but its repercussions on pediatric illnesses may have been significant. This study examines the indirect impact of the pandemic on a population of critically ill children in the United States.

RESEARCH QUESTION

Were there significantly fewer critically ill children admitted to PICUs during the second quarter of 2020, and were there significant changes in the types of diseases admitted?

STUDY DESIGN AND METHODS

This retrospective observational cohort study used the Virtual Pediatric Systems database. Participants were 160,295 children admitted to the PICU at 77 sites in the United States during quarters 1 (Q1) and 2 (Q2) of 2017 to 2019 (pre-COVID-19) and 2020 (COVID-19).

RESULTS

The average number of admissions was similar between pre-COVID-19 Q1 and COVID-19 Q1 but decreased by 32% from pre-COVID-19 Q2 to COVID-19 Q2 (20,157 to 13,627 admissions per quarter). The largest decreases were in respiratory conditions, including asthma (1,327 subjects in pre-COVID-19 Q2 (6.6% of patients) vs 241 subjects in COVID-19 Q2 (1.8%; P < .001) and bronchiolitis (1,299 [6.5%] vs 121 [0.9%]; P < .001). The percentage of trauma admissions increased, although the raw number of trauma admissions decreased. Admissions for diabetes mellitus and poisoning/ingestion also increased. In the multivariable model, illness severity-adjusted odds of ICU mortality for PICU patients during COVID-19 Q2 increased compared with pre-COVID-19 Q2 (OR, 1.165; 95% CI, 1.00-1.357; P = .049).

INTERPRETATION

Pediatric critical illness admissions decreased substantially during the second quarter of 2020, with significant changes in the types of diseases seen in PICUs in the United States. There was an increase in mortality in children admitted to the PICU during this period.

Asthma, bronchial hyperresponsiveness, allergy and lung function development until early adulthood: A systematic literature review

BACKGROUND

It is unclear in which periods of life lung function deficits develop, and whether these are affected by risk factors such as asthma, bronchial hyper-responsiveness (BHR) and allergic comorbidity. The goal of this systematic review was to identify temporal associations of asthma, BHR and allergic comorbidity with large and small lung function development from birth until peak function in early adulthood.

METHODS

We searched MEDLINE, EMBASE, Web of Science and CINAHL for papers published before 01.01.2020 on risk factors and lung function measurements of large and small airways. Studies were required to report lung function at any time point or interval from birth until peak lung function (age 21-26) and include at least one candidate risk factor.

RESULTS

Of the 45 papers identified, 44 investigated cohorts and one was a clinical trial with follow-up. Asthma, wheezing, BHR and allergic sensitization early in life and to multiple allergens were associated with a lower lung function growth of large and small airways during early childhood compared with the control populations. Lung function development after childhood in subjects with asthma or persistent wheeze, although continuing to grow at a lower level, largely tracked parallel to non-affected individuals until peak function was attained.

CLINICAL IMPLICATIONS AND FUTURE RESEARCH

Deficits in lung function growth develop in early childhood, and children with asthma, BHR and early-life IgE (poly)sensitization are at risk. This period is possibly a critical window of opportunity to identify at-risk subjects and provide treatment aimed at preventing long-term sequelae of lung function.

Cord blood group 2 innate lymphoid cells are associated with lung function at 6 weeks of age

Objective

Offspring born to mothers with asthma in pregnancy are known to have lower lung function which tracks with age. Human group 2 innate lymphoid cells (ILC2) accumulate in foetal lungs, at 10‐fold higher levels compared to adult lungs. However, there are no data on foetal ILC2 numbers and the association with respiratory health outcomes such as lung function in early life. We aimed to investigate cord blood immune cell populations from babies born to mothers with asthma in pregnancy.

Methods

Cord blood from babies born to asthmatic mothers was collected, and cells were stained in whole cord blood. Analyses were done using traditional gating approaches and computational methodologies (t‐distributed stochastic neighbour embedding and PhenoGraph algorithms). At 6 weeks of age, the time to peak tidal expiratory flow as a percentage of total expiratory flow time (tPTEF/tE%) was determined as well as Lung Clearance Index (LCI), during quiet natural sleep.

Results

Of 110 eligible infants (March 2017 to November 2019), 91 were successfully immunophenotyped (82.7%). Lung function was attempted in 61 infants (67.0%), and 43 of those infants (70.5% of attempted) had technically acceptable tPTEF/tE% measurements. Thirty‐four infants (55.7% of attempted) had acceptable LCI measurements. Foetal ILC2 numbers with increased expression of chemoattractant receptor‐homologous molecule (CRTh2), characterised by two distinct analysis methodologies, were associated with poorer infant lung function at 6 weeks of age.”

Conclusion

Foetal immune responses may be a surrogate variable for or directly influence lung function outcomes in early life.

Association between lung function and future risks of diabetes, asthma, myocardial infarction, hypertension and all-cause mortality

BACKGROUND

While forced expiratory volume in 1 s (FEV1) is a hallmark of disease progression in chronic obstructive lung diseases, little is known about the relationship between baseline FEV1 and future risks of other medical conditions.

OBJECTIVE

The aim of this study was to investigate the association between baseline FEV1 and future risks of diabetes, asthma, myocardial infarction, hypertension and all-cause mortality.

METHODS

We used data from the National Health and Nutrition Examination Survey and its Epidemiological Follow-Up Study. Our data provided longitudinal follow-up of the original cohort for up to 12 years. We used two competing risks approaches, the cause-specific hazard model and the Fine-Gray sub-distribution hazard model, to measure the associations between baseline FEV1 and future risks of the outcomes of interest. All models were adjusted for major confounding factors.

RESULTS

The final sample included 3020 participants (mean±sd baseline age 44.64±13.44 years). In the cause-specific hazard model, for every per cent increase in the baseline per cent predicted FEV1, the hazard of the event reduced by 2.5% (HR 0.975; 95% CI 0.958-0.994) for diabetes, 4.3% (HR 0.957; 95% CI 0.932-0.983) for asthma and 1.8% (HR 0.982; 95% CI 0.971-0.992) for all-cause mortality. There was no statistically significant association between baseline per cent predicted FEV1 and future risks of myocardial infarction (HR 0.987; 95% CI 0.970-1.004) and hypertension (HR 0.998; 95% CI 0.992-1.005). Consistent results were observed for the Fine-Gray sub-distribution hazard model.

CONCLUSION

Our data suggest that lower per cent predicted FEV1 values at baseline were significantly associated with higher future risks of diabetes, asthma and all-cause mortality.

Low gestational vitamin D level and childhood asthma are related to impaired lung function in high-risk children

BACKGROUND

Lung function impairment in early life often persists into adulthood. Therefore, identifying risk factors for low childhood lung function is crucial.

OBJECTIVE

We examined the effect of 25-hydroxyvitamin D (25[OH]D) level and childhood asthma phenotype on childhood lung function in the Vitamin D Antenatal Asthma Reduction Trial (VDAART).

METHODS

The 25(OH)D level was measured at set time points in mothers during pregnancy and in children during early life. On the basis of parental reports, children were categorized into 3 clinical phenotypes: asymptomatic/infrequent wheeze, early transient wheeze, and asthma at age 6 years. Lung function was assessed with impulse oscillometry at ages 4, 5, and 6 years and with spirometry at ages 5 and 6 years.

RESULTS

A total of 570 mother-child pairs were included in this post hoc analysis. Mean gestational 25(OH)D-level quartiles were negatively associated with child respiratory resistance at 5 Hz (R5) from age 4 to 6 years (β, -0.021 kPa/L/s; 95% CI, -0.035 to -0.007; P = .003) and positively associated with FEV1 (β, 0.018 L; 95% CI, 0.005-0.031; P = .008) and forced vital capacity (β, 0.022 L; 95% CI, 0.009-0.036; P = .002) from age 5 to 6 years. Children with asthma at age 6 years had lower lung function from age 4 to 6 years than the asymptomatic/infrequent wheeze group (β, 0.065 kPa/L/s; 95% CI, 0.028 to 0.102; P < .001 for R5 and β, -0.063 L; 95% CI, -0.099 to -0.028; P < .001 for FEV1).

CONCLUSIONS

Low gestational 25(OH)D level and childhood asthma are important risk factors for decreased lung function in early childhood.

FEF25-75% Is a More Sensitive Measure Reflecting Airway Dysfunction in Patients with Asthma: A Comparison Study Using FEF25-75% and FEV1

BACKGROUND

Reduced forced expiratory flow between 25% and 75% of vital capacity percent predicted (FEF_25-75%) representing small airway dysfunction (SAD) was associated with asthma development and progression.

OBJECTIVE

To investigate whether FEF_25-75% was superior to forced expiratory volume in 1 second in predicted (FEV₁%) in reflecting asthma features in adult patients.

METHODS

A retrospective spirometry dataset comprising 1801 adult patients with confirmed asthma and a subgroup of 332 patients having detailed clinical data were used to explore the association of FEF_25-75% and/or FEV₁% with clinical features of asthma.

RESULTS

Of the 1801 subjects, FEV₁% and FEF_25-75% ranged from 136.8% to 10.2% and 127.3% to 3.1%, respectively. FEF_25-75% < 65% was present in 1,478 (82.07%) of patients. FEF_25-75% was strongly correlated with matched FEV₁% (r = 0.900, P < .001). FEF_25-75% and FEV₁% were both correlated with airway hyperresponsiveness (r = 0.436, P < .001; r = 0.367, P < .001), asthma control test score (r = 0.329, P < .001; r = 0.335, P < .001), and sputum eosinophil count (r = -0.306, P < .001; r = -0.307, P < .001). Receiver-operating characteristic curves showed that FEF_25-75% had greater value in predicting severe asthma (area under the curve: 0.84 vs 0.81, P = .018), airflow obstruction (0.97 vs 0.89, P < .001), and severe bronchial hyperresponsiveness (0.74 vs 0.69, P = .012) as compared with FEV₁%. Patients with SAD (FEF_25-75% < 65%) in the presence of normal FEV₁% exhibited higher sputum eosinophil counts and had an increased dosage of daily inhaled corticosteroids (P < .001 and P = .010) than patients with normal lung function and their FEF_25-75% values correlated with sputum eosinophil count (r = -0.419, P = .015), but not FEV₁%.

CONCLUSION

FEF_25-75% represented small airway function and was more sensitive at reflecting airway hyperresponsiveness, inflammation, and disease severity as compared with FEV₁% in patients with asthma. Our data suggest further assessment of FEF_25-75% in asthma management, particularly for those with SAD who present normal FEV₁%.

Early Life Wheeze and Risk Factors for Asthma-A Revisit at Age 7 in the GEWAC-Cohort

One third of all toddlers are in need of medical care because of acute wheeze and many of these children have persistent asthma at school age. Our aims were to assess risk factors for and the prevalence of asthma at age 7 in a cohort of children suffering from an acute wheezing episode as toddlers. A total of 113 children, included during an acute wheezing episode (cases), and 54 healthy controls were followed prospectively from early pre-school age to 7 years. The protocol included questionnaires, ACT, FeNO, nasopharyngeal virus samples, blood sampling for cell count, vitamin D levels, and IgE to food and airborne allergens. The prevalence of asthma at age 7 was 70.8% among cases and 1.9% among controls (p < 0.001). Acute wheeze caused by rhinovirus (RV) infection at inclusion was more common among cases with asthma at age 7 compared to cases without asthma (p = 0.011) and this association remained significant following adjustment for infection with other viruses (OR 3.8, 95% CI 1.4–10.5). Cases with asthma at age 7 had been admitted to hospital more often (p = 0.024) and spent more days admitted (p = 0.01) during the year following inclusion compared to cases without asthma. RV infection stands out as the main associated factor for wheeze evolving to persistent asthma. Cases who developed asthma also had an increased need of hospital time and care for wheeze during the year after inclusion.

Nasal upregulation of CST1 in dog-sensitised children with severe allergic airway disease

Background

The clinical presentation of children sensitised to dog dander varies from asymptomatic to severe allergic airway disease, but the genetic mechanisms underlying these differences are not clear. The objective of the present study was to investigate nasal transcriptomic profiles associated with dog dander sensitisation in school children and to reveal clinical symptoms related with these profiles.

Methods

RNA was extracted from nasal epithelial cell brushings of children sensitised to dog dander and healthy controls. Blood sample analyses included IgE against dog dander, dog allergen molecules, other airborne and food allergens, basophil activation and white blood cell counts. Clinical history of asthma and rhinitis was recorded, and lung function was assessed (spirometry, methacholine provocation and exhaled nitric oxide fraction).

Results

The most overexpressed gene in children sensitised to dog dander compared to healthy controls was CST1, coding for Cystatin 1. A cluster of these children with enhanced CST1 expression showed lower forced expiratory volume in 1 s, increased bronchial hyperreactivity, pronounced eosinophilia and higher basophil allergen threshold sensitivity compared with other children sensitised to dog dander. In addition, multi-sensitisation to lipocalins was more common in this group.

Conclusions

Overexpression of CST1 is associated with more severe allergic airway disease in children sensitised to dog dander. CST1 is thus a possible biomarker of the severity of allergic airway disease and a possible therapeutic target for the future treatment of airborne allergy.

Initiation and Pathogenesis of Severe Asthma with Fungal Sensitization

Fungi represent one of the most diverse and abundant eukaryotes on earth, and their ubiquity and small proteolytically active products make them pervasive allergens that affect humans and other mammals. The immunologic parameters surrounding fungal allergies are still not fully elucidated despite their importance given that a large proportion of severe asthmatics are sensitized to fungal allergens. Herein, we explore fungal allergic asthma with emphasis on mouse models that recapitulate the characteristics of human disease, and the main leukocyte players in the pathogenesis of fungal allergies. The endogenous mycobiome may also contribute to fungal asthma, a phenomenon that we discuss only superficially, as much remains to be discovered.

Association of early life and acute pollen exposure with lung function and exhaled nitric oxide (FeNO). A prospective study up to adolescence in the GINIplus and LISA cohort

BACKGROUND

Pollen exposure has both acute and chronic detrimental effects on allergic asthma, but little is known about its wider effects on respiratory health. This is increasingly important knowledge as ambient pollen levels are changing with the changing global climate.

OBJECTIVE

To assess associations of pollen exposure with lung function and fractional exhaled nitric oxide (FeNO) at age 15 in two prospective German birth cohorts, GINIplus and LISA.

METHODS

Background city-specific pollen exposure was measured in infancy (during the first three months of life), and contemporary (on the day of and 7 days prior to lung function measurement). Greenness levels within circular buffers (100-3000 m) around the birth and 15-year home addresses were calculated using the satellite-derived Normalized Difference Vegetation Index. Regression models were used to assess the associations of grass and birch pollen with lung function and FeNO, and the modifying effects of residential greenness were explored.

RESULTS

Cumulative early life exposure to grass pollen was associated with reduced lung function in adolescence (FEV₁: -4.9 mL 95%CI: -9.2, -0.6 and FVC: -5.2 mL 95%CI: -9.8, -0.5 per doubling of pollen count). Acute grass pollen exposure was associated with increased airway inflammation in all children, with higher FeNO increases in children living in green areas. In contrast acute birch pollen exposure was associated with reduced lung function only in children sensitised to birch allergens.

CONCLUSION

This study provides suggestive evidence that early pollen exposure has a negative effect on later lung function, which is in turn influenced by acute pollen exposures.

Lung function testing and inflammation markers for wheezing preschool children: A systematic review for the EAACI Clinical Practice Recommendations on Diagnostics of Preschool Wheeze

BACKGROUND

Preschool wheeze is highly prevalent; 30%-50% of children have wheezed at least once before age six. Wheezing is not a disorder; it is a symptom of obstruction in the airways, and it is essential to identify the correct diagnosis behind this symptom. An increasing number of studies provide evidence for novel diagnostic tools for monitoring and predicting asthma in the pediatric population. Several techniques are available to measure airway obstruction and airway inflammation, including spirometry, impulse oscillometry, whole-body plethysmography, bronchial hyperresponsiveness test, multiple breath washout test, measurements of exhaled NO, and analyses of various other biomarkers.

METHODS

We systematically reviewed all the existing techniques available for measuring lung function and airway inflammation in preschool children to assess their potential and clinical value in the routine diagnostics and monitoring of airway obstruction.

RESULTS

If applicable, measuring FEV1 using spirometry is considered useful. For those unable to perform spirometry, whole-body plethysmography and IOS may be useful. Bronchial reversibility to beta2-agonist and hyperresponsiveness test with running exercise challenge may improve the sensitivity of these tests.

CONCLUSIONS

The difficulty of measuring lung function and the lack of large randomized controlled trials makes it difficult to establish guidelines for monitoring asthma in preschool children.

COVID-19: Why does disease severity vary among individuals?

The novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is responsible for the current pandemic, coronavirus disease 2019 (COVID-19). While all people are susceptible to the SARS-CoV-2 infection, the nature and severity of the disease vary significantly among individuals and populations. Importantly, reported disease burdens and case fatality rates differ considerably from country to country. There are, however, still uncertainties about the severity of the disease among individuals or the reason behind a more severe disease in some cases. There is a strong possibility that the severity of this disease depends on a complicated interaction between the host, virus, and environment, which leads to different clinical outcomes. The objective of this article is to point out the essential influential factors related to the host, virus, and environment affecting the clinical outcome of COVID-19.

Severe acute respiratory syndrome coronavirus 2 prevalence in 1170 asymptomatic Norwegian conscripts

BACKGROUND

Accurate estimates of SARS-CoV-2 infection in different population groups are important for the health authorities. In Norway, public infection control measures have successfully curbed the pandemic. However, military training and service are incompatible with these measures; therefore extended infection control measures were implemented in the Norwegian Armed Forces. We aimed to describe these measures, discuss their value, and investigate the polymerase chain reaction (PCR) prevalence and seroprevalence of SARS-CoV-2, as well as changes in antibody titer levels over the 6-week military training period in a young, asymptomatic population of conscripts.

METHODS

In April 2020, 1170 healthy conscripts (median age 20 years) enrolled in military training. Extended infection control measures included a pre-enrollment telephone interview, self-imposed quarantine, questionnaires, and serial SARS-CoV-2 testing. At enrollment, questionnaires were used to collect information on symptoms, and SARS-CoV-2 rapid antibody testing was conducted. Serial SARS-CoV-2 PCR and serology testing were used to estimate the prevalence of confirmed SARS-CoV-2 and monitor titer levels at enrollment, and 3 and 6 weeks thereafter.

RESULTS

At enrollment, only 0.2% of conscripts were SARS-CoV-2 PCR-positive, and seroprevalence was 0.6%. Serological titer levels increased nearly 5-fold over the 6-week observation period. Eighteen conscripts reported mild respiratory symptoms during the 2 weeks prior to enrollment (all were PCR-negative; one was serology-positive), whereas 17 conscripts reported respiratory symptoms and nine had fever at enrollment (all were PCR- and serology-negative).

CONCLUSIONS

The prevalence of SARS-CoV-2 was less than 1% in our sample of healthy Norwegian conscripts. Testing of asymptomatic conscripts seems of no value in times of low COVID-19 prevalence. SARS-CoV-2 antibody titer levels increased substantially over time in conscripts with mild symptoms.

A systematic review of asthma case definitions in 67 birth cohort studies

BACKGROUND

Birth cohort studies are a valuable source of information about potential risk factors for childhood asthma. To better understand similarities and variations in findings between birth cohort studies, the methodologies used to measure asthma require consideration.

OBJECTIVE

To review and appraise the definitions of "asthma" used in birth cohort studies.

METHODS

A literature search, conducted in December 2017 in the MEDLINE database and birth cohort repositories, identified 1721 citations published since 1990. Information extracted included: study name, year of publication, sample size, sample age, prevalence of asthma (%), study region, source of information about asthma, measured outcome, and asthma case definition. A meta-analysis evaluated whether asthma prevalence in cohorts from Europe and North America varied by the studies' definition of asthma and by their data sources.

RESULTS

The final review included 67 birth cohorts, of which 48 (72%) were from Europe, 14 (21%) from North America, 3 (5%) from Oceania, 1 (1%) from Asia and 1 (1%) from South America. We identified three measured outcomes: "asthma ever", "current asthma", and "asthma" without further specification. Definitions of "asthma ever" were primarily based upon an affirmative parental response to the question whether the child had ever been diagnosed with asthma by a physician. The most frequently used definition of "current asthma" was "asthma ever" and either asthma symptoms or asthma medications in the last 12 months. This definition of "current asthma" was used in 16 cohorts. There was no statistically significant difference in the pooled asthma prevalence in European and North American cohorts that used questionnaire alone versus other data sources to classify asthma.

CONCLUSION

There is substantial heterogeneity in childhood asthma definitions in birth cohort studies. Standardisation of asthma case definitions will improve the comparability and utility of future cohort studies and enable meta-analyses.

Maternal asthma is associated with reduced lung function in male infants in a combined analysis of the BLT and BILD cohorts

RATIONALE

Asthma in pregnancy is associated with respiratory diseases in the offspring.

OBJECTIVE

To investigate if maternal asthma is associated with lung function in early life.

METHODS

Data on lung function measured at 5-6 weeks of age were combined from two large birth cohorts: the Bern Infant Lung Development (BILD) and the Australian Breathing for Life Trial (BLT) birth cohorts conducted at three study sites (Bern, Switzerland; Newcastle and Sydney, Australia). The main outcome variable was time to reach peak tidal expiratory flow as a percentage of total expiratory time(tPTEF:tE%). Bayesian linear hierarchical regression analyses controlling for study site as random effect were performed to estimate the effect of maternal asthma on the main outcome, adjusting for sex, birth order, breast feeding, weight gain and gestational age. In separate adjusted Bayesian models an interaction between maternal asthma and sex was investigated by including an interaction term.

MEASUREMENTS AND MAIN RESULTS

All 406 BLT infants were born to mothers with asthma in pregnancy, while 193 of the 213 (91%) BILD infants were born to mothers without asthma. A significant interaction between maternal asthma and male sex was negatively associated with tPTEF:tE% (intercept 37.5; estimate: -3.5; 95% credible interval -6.8 to -0.1). Comparing the model posterior probabilities provided decisive evidence in favour of an interaction between maternal asthma and male sex (Bayes factor 33.5).

CONCLUSIONS

Maternal asthma is associated with lower lung function in male babies, which may have lifelong implications on their lung function trajectories and future risk of wheezing and asthma.

Factors Associated with the Development of Childhood Asthma in Japan: A Nationwide Longitudinal Study

INTRODUCTION

Many environmental factors are related to the development of asthma. However, the key factors of childhood asthma onset have not been sufficiently elucidated. Further, low-weight births have increased in Japan. The aim of this study was to examine the risk factors for the incidence of childhood asthma and to evaluate whether these risk factors differ according to birth weight in Japan.

METHODS

We used the National Longitudinal Survey from 2001 to 2010. Multiple logistic regression analyses were conducted to determine the effects of gender, birth weight, single vs. multiple births, birth order, nutrition, keeping pets in the home, place of residence, annual household income, and parent ages, smoking behaviors, and educational backgrounds on asthma-related hospital visits.

RESULTS

Overall, 45,060 children were analyzed. The rate of cumulative hospital visits until age 10 was 18.9%. Birth weight < 2500 g (adjusted odds ratio [AOR] = 1.14, 95% confidence interval [CI] 1.03-1.26), being a boy (AOR = 1.27, 95% CI 1.21-1.33), having older siblings (AOR = 1.07, 95% CI 1.02-1.14), parental smoking behavior, mother`s age, and low household income (AOR = 1.17, 95% CI 1.10-1.24) were associated with asthma-related hospital visits.

DISCUSSION

Parental smoking behavior is a key risk factor for the development of asthma. Among low birth weight infants, being a boy, having older siblings, and father`s smoking behavior were predictive factors for the development of asthma. However, low birth weight was not associated with the development of asthma after 6 years of age.

Parameters of cardiac symptoms in young athletes using the Heartbytes database

Introduction: To determine clinical parameters that are related to abnormal cardiac symptoms in physically active youth. Methods: We used Simon's Heart Heartbytes National Youth Cardiac Registry to collect data from adolescent athletes in southeastern Pennsylvania. We collected age, race/ethnicity, abnormal cardiac symptoms, medical history, medication use, caffeine intake, and family history. We obtained height, weight, blood pressure, cardiac murmur findings, and ECGs. Echocardiogram was obtained if necessary. Binary logistic regression analysis was performed to identify independent associations between abnormal cardiac symptoms and collected variables. The odds ratio (OR), 95% confidence interval (95% CI), and p-values were used as statistical values. Results: Of the 887 athletes (543 males and 344 females, age = 16.9 ± 2.1 years, height = 166.9 ± 11.4 cm, weight = 62.0 ± 16.0 kg), 186 (21%) had abnormal cardiac symptoms including chest pain, passing out, difficulty breathing, extreme fatigue, and heart race. There was an independent association between abnormal symptoms and a past medical history (OR: 4.77, 95%CI: 3.18, 7.17, p = 0.001) and medication use (OR: 1.74, 95%CI: 1.08, 2.79, p = 0.022). In medical history, young athletes with asthma showed a greater propensity of abnormal cardiac symptoms (48.9%) compared to young athletes without (14.0%, p = 0.001). Additionally, young athletes with anxiety or depression demonstrated a higher proportion of abnormal cardiac symptoms (48.9%) than those without (19.5%, p = 0.001). Although the association between the presence of abnormal symptoms and African-American race (OR: 2.04, 95%CI: 0.96, 4.35, p = 0.065) and average daily consumption of at least 2 caffeine drinks (OR: 2.08, 95%CI: 0.86, 5.02, p = 0.103) were not significant, there was a trend to reach the a priori significance level. Conclusions: This study identified several clinical parameters that are associated with symptoms suggestive of abnormal cardiac conditions. Larger studies need to be done to better sort out the clinical history that may contribute to false positives to further reduce false positives at heart screenings.

Impact of the COVID-19 pandemic on the Emergency Department of a tertiary children's hospital

BACKGROUND

Italy was the first country in Europe affected by COVID-19: the emergency started on February 20, 2020, culminating with national lockdown on March 11, which terminated on May 4, 2020. We describe how the pandemic affected Emergency Department (ED) accesses in a tertiary children's hospital, composed by two different pediatric centers, one located in Rome's city center and the second, Palidoro (regional COVID-19 center), in its surrounding metropolitan area, both in the Lazio region, analyzing the profile of admitted patients during the pandemic period in terms of their general characteristics (at presentation in the ED's) and urgent hospitalizations compared to prepandemic period.

METHODS

The study compare the period between the 21st of February and the 30th of April 2020, covering the three phases of the national responses (this period will be referred to as the pandemic period) with the same period of 2019 (prepandemic period). The study analyzes the number of ED visits and urgent hospitalizations and their distribution according to selected characteristics.

RESULTS

The reduction of ED visits was 56 and 62%, respectively in Rome and Palidoro centers. The higher relative decline was encountered for Diseases of Respiratory System, and for Diseases of the Nervous System and Sense Organs. A doubling of the relative frequency of hospitalizations was observed, going from 14.2 to 24.4% in Rome and from 6.4 to 10.3% in Palidoro. In terms of absolute daily numbers the decrease of urgent hospitalizations was less sharp than ED visits. For pathologies such as peritonitis, tumors or other possible life-treathening conditions we did not observe a significative increase due to delayed access.

CONCLUSIONS

In the pandemic period there was a general reduction in the number of children referred to ED, such reduction was greater in low-acuity levels. The reduction for respiratory tract infections and other communicable diseases during school closure and the national lockdown must make us reflect on the possible impact that these conditions may have on the health system, in particular the ED, at the reopening of schools. The major problem remains the fear for possible diagnostic delays in life-threatening or crippling diseases; our study doesn't demonstrate an increase in number or significant delay in some serious conditions such as tumors, peritonitis, diabetic ketoacidosis, ileo-colic intussusception and testis/ovary torsion. A continuous, deep re-organizational process step by step of the ED is nececessary in the present and upcoming pandemic situation.

Precision medicine in severe pediatric asthma: opportunities and challenges

Purpose of review

Severe pediatric asthma exerts a substantial burden on patients, their families and society. This review provides an update on the latest insights and needs regarding the implementation of precision medicine in severe pediatric asthma.

Recent findings

Biologicals targeting underlying inflammatory pathways are increasingly available to treat children with severe asthma, holding the promise to enable precision medicine in this heterogeneous patient population with high unmet clinical needs. However, the current understanding of which child would benefit from which type or combination of biologicals is still limited, as most evidence comes from adult studies and might not be generalizable to the pediatric population. Studies in pediatric severe asthma are scarce due to the time-consuming effort to diagnose severe asthma and the challenge to recruit sufficient study participants. The application of innovative systems medicine approaches in international consortia might provide novel leads for – preferably noninvasive – new biomarkers to guide precision medicine in severe pediatric asthma.

Summary

Despite the increased availability of targeted treatments for severe pediatric asthma, clinical decision-making tools to guide these therapies are still lacking for the individual pediatric patient.

Tidal breath in healthy term newborns: An analysis from the 2nd to the 30th days of life

BACKGROUND

Few data are available concerning normative lung function parameters measured in unsedated neonates.

AIM

To evaluate lung function changes in neonates.

METHODS

In this prospective cohort study, tidal breath parameters were measured using the MasterScreen PAED system and standardized protocols. Measurements were performed on 60 (30 male) term, healthy, unsedated neonates on the postnatal 2nd and 30th days.

RESULTS

Expiratory time (TE; p < .001; Cohen's d = 0.561), exhaled volume to peak tidal expiratory flow (VPTEF; p < .001; Cohen's d = 0.789), minute ventilation (p < .001; Cohen's d = 0.926), tidal volume (VT; p < .001; Cohen's d = 1.835), expiratory flow when 75%, 50%, and 25% of tidal volume remaining in the lungs (TEF75 [p < .001; Cohen's d = 1.070], TEF50 [p < .001; Cohen's d = 0.824], TEF25 [p < .001; Cohen's d = 0.568]), and inspiratory time (Ti; p < .001; Cohen's d = 0.654) were higher on Day 30 compared to Day 2, while time to reach peak tidal expiratory flow to total expiratory time (TPTEF/TE; p = .006; Cohen's d = 0.371), the volume until peak tidal expiratory flow to total expiratory volume (VPTEF/VE; p = .001; Cohen's d = 0.447), and respiration rate (RR; p = .001; Cohen's d = 0.432) were lower, and Ti/TE was unchanged. Positive correlation was observed between length and VT (r = .347; p = .008) on Day 2 and (r = .338; p = .008) on Day 30.

CONCLUSIONS

The present study reveals the physiological changes occurring in lung functions in healthy term neonates during the neonatal period.