The Annual September Peak in Asthma Exacerbation Rates. Still a Reality?

Asthma as a Risk Factor for Hospitalization in Children and Youth With COVID-19: A Retrospective Cohort Study

BACKGROUND

Studies examining the association between asthma and hospitalization among children and youth with coronavirus disease 2019 (COVID-19) have yielded mixed results. Both asthma and COVID-19 hospitalization are characterized by racial, ethnic and socioeconomic disparities which also pattern geographically, yet no studies to date have adjusted for neighborhood context in the assessment of this association.

METHODS

Mixed effects logistic regression was used to estimate the association between asthma and hospitalization due to COVID-19 in a sample of 28,997 children and youth diagnosed with COVID-19 in Milwaukee County, Wisconsin, from March 1, 2020, to May 31, 2022. Models adjusted for individual-level sociodemographic factors (age, gender, race, ethnicity and city/suburb residence) and season of diagnosis were examined as moderators. Random intercepts by census tract accounted for geographic variation in neighborhood factors and census tract-level measures of education, health and environment, and social and economic factors were assessed via childhood opportunity indices.

RESULTS

Asthma history was statistically significantly associated with hospitalization due to COVID-19 among children and youth. Hospitalization rates varied statistically significantly by census tract, and results were unchanged after accounting for childhood opportunity indices and census tract. Season of diagnosis was not found to moderate the effect of asthma history on COVID-19 hospitalization.

CONCLUSION

Our study suggests that asthma history is a risk factor for hospitalization in the context of COVID-19 infection among children and youth, warranting observation and follow-up of children with asthma as well as continued measures to prevent COVID-19 in this population.

The acute care burden of asthma in children was profoundly reduced during the COVID-19 pandemic: A multi-centre Canadian retrospective study

Objectives

Asthma is a chronic lung condition that can be exacerbated when triggered by viruses. Pandemic public health restrictions aimed to reduce COVID-19 transmission indirectly effected other circulating viruses. This study assessed the impact of the pandemic and associated public health measures on acute paediatric asthma across four tertiary sites in three Canadian provinces. We queried whether pandemic-related changes would impair preventive care and delay presentation to care, increasing asthma exacerbation severity.

Methods

This retrospective study compared the frequency of acute care access and severity of presentation to emergency departments (ED) for acute asthma to four tertiary care children's hospitals during the COVID-19 pandemic (from March 17, 2020 to June 30, 2021) to a pre-lockdown control period (July 1, 2018 to March 16, 2020). Data was subjected to interrupted time series and Chi-square analysis.

Results

Our study included 26,316 acute asthma visits to ED. Sites experienced a 63% to 89% reduction in acute asthma visits during the pandemic, compared with pre-lockdown controls, and a 17% to 85% reduction in asthma, that is out of proportion as a fraction of all-cause ED visits. For asthma, there was no difference in severity measured by rate of ward admission or rate of Paediatric Intensive Care Unit (PICU) admission.

Conclusions

Public health measures appear to have resulted in a specific protective association on acute asthma with reduced acute care utilization over and above the reduction in all-cause presentations, without an increase in severity upon presentation. Our study indicates an importance to antiviral public health and engineering strategies to reduce viral transmission and thereby asthma morbidity.

Allergen Immunotherapy for Asthma

Allergen immunotherapy is a disease-modifying treatment for IgE-mediated allergies reducing disease burden and symptoms in patients with allergic rhinitis, with or without asthma. The growing evidence that allergen immunotherapy also has the potential to facilitate achieving asthma control in patients with allergic asthma resulted in its acknowledgment by international bodies (Global Initiative for Asthma and European Academy of Allergy and Clinical Immunology) as add-on treatment for mild/moderate asthma. Although there have been promising developments in biomarkers for patient selection and for allergen immunotherapy efficacy evaluation in patients with asthma, a lot more data are still required.

Prediction of Asthma Exacerbations in Children

Asthma exacerbations are common in asthmatic children, even among those with good disease control. Asthma attacks result in the children and their parents missing school and work days; limit the patient's social and physical activities; and lead to emergency department visits, hospital admissions, or even fatal events. Thus, the prompt identification of asthmatic children at risk for exacerbation is crucial, as it may allow for proactive measures that could prevent these episodes. Children prone to asthma exacerbation are a heterogeneous group; various demographic factors such as younger age, ethnic group, low family income, clinical parameters (history of an exacerbation in the past 12 months, poor asthma control, poor adherence to treatment, comorbidities), Th2 inflammation, and environmental exposures (pollutants, stress, viral and bacterial pathogens) determine the risk of a future exacerbation and should be carefully considered. This paper aims to review the existing evidence regarding the predictors of asthma exacerbations in children and offer practical monitoring guidance for promptly recognizing patients at risk.

Tezepelumab reduces exacerbations across all seasons in patients with severe, uncontrolled asthma (NAVIGATOR)

BACKGROUND

Asthma exacerbation frequencies vary throughout the year owing to seasonal triggers. Tezepelumab is a human monoclonal antibody that targets thymic stromal lymphopoietin. In the phase 3 NAVIGATOR study (NCT03347279), tezepelumab significantly reduced the annualized asthma exacerbation rate (AAER) vs placebo in patients with severe, uncontrolled asthma.

OBJECTIVE

To evaluate the effect of tezepelumab on asthma exacerbations across all seasons in NAVIGATOR patients (post hoc).

METHODS

NAVIGATOR was a multicenter, randomized, double-blind, placebo-controlled study. Patients (12-80 years old) were randomized 1:1 to tezepelumab 210 mg or placebo subcutaneously every 4 weeks for 52 weeks. AAER over 52 weeks was assessed by season. Data from patients in the Southern Hemisphere were transformed to align with Northern Hemisphere seasons.

RESULTS

Tezepelumab reduced the AAER vs placebo by 63% (95% confidence interval [CI], 52-72) in winter, 46% (95% CI, 26-61) in spring, 62% (95% CI, 48-73) in summer, and 54% (95% CI, 41-64) in fall. In matched climates, during the spring allergy season (March 1 to June 15) and ragweed allergy season (September), tezepelumab reduced the AAER vs placebo in patients with seasonal allergy by 59% (95% CI, 29-77) and 70% (95% CI, 33-87), respectively. In patients with perennial allergy and in those with seasonal allergy, tezepelumab reduced the AAER vs placebo across all seasons.

CONCLUSION

Tezepelumab reduced exacerbations across all seasons vs placebo in patients with severe, uncontrolled asthma, including patients with seasonal and perennial allergies. These data further support the efficacy of tezepelumab in a broad population of patients with severe, uncontrolled asthma.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03347279 (https://clinicaltrials.gov/ct2/show/NCT03347279).

Effect of lockdowns on the epidemiology of pediatric respiratory disease-A retrospective analysis of the 2021 summer epidemic

BACKGROUND

The imposition of lockdowns during the severe acute respiratory syndrome coronavirus-2 pandemic led to a significant decrease in pediatric care utilization in 2020. After restrictions were loosened, a surge in pediatric respiratory disease was observed in pediatric wards. The aim of this study was to quantify the effect of the lockdown(s) on the incidence of pediatric respiratory disease.

METHODS

For this multicenter retrospective study, emergency department (ED) visit and admission data between January 2017 and September 2021 was collected from eight general hospitals in the Netherlands. Clinical diagnoses were extracted and categorized in groups ("communicable infectious disease," "all respiratory infections," "upper respiratory tract infection," "lower respiratory tract infection," and "asthma/preschool wheezing"). The incidence of admissions and ED visits during 2020 and 2021 was compared to the incidence in 2017-2019.

RESULTS

Successive lockdowns resulted in a maximum decrease of 61% and 57% in ED visits and admissions, respectively. After loosening restrictions during the summer of 2021, a 48% overall increase in ED visits and 31% overall increase in admission numbers was observed in July compared to the average July in 2017-2019. This was explained by a 381% increase in ED visits and a 528% increase in ward admissions due to overall respiratory infections, mainly due to lower respiratory tract infections.

CONCLUSIONS

Successive lockdowns in the spring and winter of 2020 and 2021 led to a decreased incidence of communicable infections, especially respiratory tract infections. The resulting lack of pediatric immunity resulted in an off-season surge in care utilization at an unexpected moment.

Impacts of Wildfire Smoke and Air Pollution on a Pediatric Population with Asthma: A Population-Based Study

Wildfires are increasing yearly in number and severity as a part of the evolving climate crisis. These fires are a significant source of air pollution, a common driver of flares in cardiorespiratory disease, including asthma, which is the most common chronic disease of childhood. Poorly controlled asthma leads to significant societal costs through morbidity, mortality, lost school and work time and healthcare utilization. This retrospective cohort study set in Calgary, Canada evaluates the relationship between asthma exacerbations during wildfire smoke events and equivalent low-pollution periods in a pediatric asthma population. Air pollution was based on daily average levels of PM_2.5. Wildfire smoke events were determined by combining information from provincial databases and local monitors. Exposures were assumed using postal codes in the health record at the time of emergency department visits. Provincial claims data identified 27,501 asthma exacerbations in 57,375 children with asthma between 2010 to 2021. Wildfire smoke days demonstrated an increase in asthma exacerbations over the baseline (incidence rate ratio: 1.13; 95% CI: 1.02-1.24); this was not seen with air pollution in general. Increased rates of asthma exacerbations were also noted yearly in September. Asthma exacerbations were significantly decreased during periods of COVID-19 healthcare precautions.

The effect of the COVID-19 pandemic on pediatric asthma-related emergency department visits and hospital admissions in Montréal, Quebec: a retrospective cohort study

BACKGROUND

Asthma is a chronic respiratory condition that affects 10% of Canadian children and is often exacerbated by viral respiratory infections, prompting concerns about the severity of SARS-CoV-2 disease in children with asthma. We compared sociodemographic and clinical characteristics of children presenting to the emergency department and the incidence of these visits, before and during the pandemic.

METHODS

We included children aged 0 to 17 years presenting with asthma to 2 tertiary pediatric emergency departments in Montréal, Quebec, between the prepandemic (Jan. 1, 2017, to Mar. 31, 2020) and pandemic (Apr. 1, 2020, to June 30, 2021) periods. We compared the number of emergency department visits and hospital admissions with an interrupted time series analysis and compared the sociodemographic characteristics based on the Canadian Index of Multiple Deprivation (CIMD) and clinical characteristics (including triage level, intensive care admissions, etc.) with Mann-Whitney and χ² tests.

RESULTS

We examined 22 746 asthma-related emergency department visits. During the pandemic, a greater proportion of patients presented a triage level 1 or 2 (19.3% v. 14.7%) and were admitted to the intensive care unit (2.5% v. 1.3%). The patients' CIMD quintile distributions did not differ between the 2 periods. We found a 47% decrease (relative risk [RR] 0.53, 95% confidence interval [CI] 0.37 to 0.76) in emergency department visits and a 49% decrease (RR 0.51, 95% CI 0.34 to 0.76) in hospital admissions during the pandemic.

INTERPRETATION

The decrease in asthma-related emergency department visits was observed through the third wave of the pandemic, but children presented with a higher acuity and with no identified sociodemographic changes. Future studies are required to understand individual behaviours that may have led to the increased acuity at presentation observed in this study.

The Impact of Coronavirus Disease 2019 on Pediatric Asthma in the United States

The coronavirus disease 2019 (COVID-19) pandemic has caused severe economic and health impacts in the United States, and the impact is disproportionately more in socially disadvantages areas. The available data, albeit limited in children, suggest that the initial concerns of the potential of serious impact of COVID-19 illness in children with asthma are unproven so far. The reduction in asthma morbidities is due to improved adherence, COVID-19 control measures, school closures, and decreased exposure to allergens and viral infections in children. During the pandemic, asthma guidelines were updated to guide physicians in asthma care. In the face of unprecedented time, it is important to be vigilant, adhere to treatment guidelines, and implement preventive measures to eradicate the virus and improve outcomes in children with asthma.

Comparison of childhood asthma incidence in 3 neighbouring cities in southwestern Ontario: a 25-year longitudinal cohort study

BACKGROUND

Air pollution is a known trigger for exacerbations among individuals with asthma, but its role in the development of new-onset asthma is unclear. We compared the rate of new asthma cases in Sarnia, a city with high pollution levels, with the rates in 2 neighbouring regions in southwestern Ontario, Canada.

METHODS

Using a population-based birth cohort design and linked health administrative data, we compared the hazard of incident asthma among children 0 to 10 years of age between those born in Lambton (Sarnia) and those born in Windsor and London-Middlesex, for the period Apr. 1, 1993, to Mar. 31, 2009. We used Cox proportional hazards models to adjust for year of birth and exposure to air pollutants (nitrogen dioxide, sulphur dioxide [SO₂], ozone and small particulate matter [PM_2.5]), as well as maternal, geographic and socioeconomic factors.

RESULTS

Among 114 427 children, the highest incidence of asthma was in Lambton, followed by Windsor and London-Middlesex (30.3, 24.4 and 19.8 per 1000 person-years, respectively; p < 0.001). Relative to Lambton, the hazard of asthma, adjusted for socioeconomic and perinatal factors, was lower in Windsor (hazard ratio [HR] 0.72, 95% confidence interval [CI] 0.67-0.77) and London-Middlesex (HR 0.65, 95% CI 0.61-0.69). Inclusion of air pollutants attenuated this relative difference in both Windsor (HR 0.79, 95% CI 0.62-1.01) and London-Middlesex (HR 0.89, 95% CI 0.64-1.24).

INTERPRETATION

We identified a higher incidence of asthma among children born in Lambton (Sarnia) relative to 2 other regions in southwestern Ontario. Higher levels of air pollution (particularly SO₂ and PM_2.5) in this region, as experienced by children in their first year of life, may be contributory.

Emergency department visits and hospitalisations for asthma, COPD and respiratory tract infections: what is the role of respiratory viruses, and return to school in September, January and March?

Background

Asthma exacerbations increase in September coinciding with children returning to school. The aim of this study was to investigate whether this occurs 1) for COPD and respiratory tract infections (RTIs); 2) after school resumes in January and March; and 3) identify which viruses may be responsible.

Methods

Emergency department (ED) visits and admissions for asthma, COPD and RTIs and the prevalence of viruses in Ontario, Canada were analysed daily between 2003 and 2013. ED visits and admissions were provided by the Canadian Institute for Health Information. Viral prevalence was obtained from the Centre for Immunisation and Respiratory Infectious Diseases.

Results

ED visits and admissions rates demonstrated a biphasic pattern. Lowest rates occurred in July and August and the highest rates in September for asthma, and after December for COPD and RTI. The increase in rates for 30 days before and after school return in September was greatest for children with asthma <15 years (2.4–2.6×). Event rates fell after school return in January for all three conditions ranging from 10–25%, and no change followed March break for asthma and COPD. Human rhinovirus was prevalent in summer with a modest relationship to asthma rates in September. The prevalence of respiratory syncytial virus, influenza A and coronavirus was associated with sustained event rates for COPD and RTIs.

Conclusions

Asthma, COPD and RTIs increase in September but do not occur after return to school in January and March. Human rhinovirus is associated with ED visits and admissions only in September.

Asthma, COPD and RTIs increase in September but do not occur after return to school in January and March. Human RV is associated with ED visits and admissions only in September.https://bit.ly/3jEy168

Impact of season and geography on CompEx Asthma: a composite end-point for exacerbations

Background

CompEx Asthma, a novel composite end-point combining severe exacerbations (SevEx) with asthma-worsening events, was recently developed. Further characterisation of CompEx Asthma is needed to illustrate the applicability of this end-point. The objective was to evaluate CompEx Asthma as a rate end-point to determine how seasonal and geographical factors impact this novel outcome.

Methods

Seven 24–56-week randomised controlled trials of budesonide/formoterol (BUD/FORM) and benralizumab were analysed. Annualised event rates (AERs) and treatment effects (hazard ratio (HR)) were analysed with Poisson and Andersen–Gill models, respectively. Seasonality was analysed by month and five geographical regions were evaluated.

Results

The studies included 10 815 patients (63% female, mean age 42–49 years). CompEx Asthma AER mirrored seasonal variations in SevEx AER. CompEx Asthma AERs were higher versus SevEx in BUD/FORM and benralizumab trials (range 2.7–4.5-fold and 1.3–2.0-fold increase, respectively) and were less variable versus SevEx between regions (ratios of greatest:smallest AERs: 1.36 for CompEx versus 2.28 for SevEx (BUD/FORM); 1.81 for CompEx versus 2.22 for SevEx (benralizumab)). Treatment effects for CompEx Asthma and SevEx were generally similar across regions and months. However, in Eastern Europe, where SevEx rates were lowest, treatment effect was greater with CompEx Asthma versus SevEx, reaching statistical significance in the benralizumab studies (HR (95% CI): 0.67 (0.53–0.85) versus 0.87 (0.65–1.15)).

Conclusion

This study confirmed the reliability of CompEx Asthma as a rate end-point and allowed detection of variations in seasonal SevEx rates, reduction of variation in rates across regions and potential greater sensitivity to treatment effects.

CompEx Asthma is a valid end-point that reflects the treatment efficacy observed on SevEx when studying recurrent events and may enable smaller, 3-month clinical trials factoring in seasonal variationhttps://bit.ly/3jPI894

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

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

School-Based Telemedicine Interventions for Asthma: A Systematic Review

BACKGROUND

School health systems are increasingly investing in telemedicine platforms to address acute and chronic illnesses. Asthma, the most common chronic illness in childhood, is of particular interest given its high burden on school absenteeism.

OBJECTIVE

Conduct a systematic review evaluating impact of school-based telemedicine programs on improving asthma-related outcomes.

DATA SOURCES

PubMed, Cochrane CENTRAL, CINAHL, ERIC, PsycINFO, Embase, and Google Scholar.

STUDY ELIGIBILITY CRITERIA

Original research, including quasi-experimental studies, without restriction on the type of telemedicine.

PARTICIPANTS

School-aged pediatric patients with asthma and their families.

INTERVENTIONS

School-based telemedicine.

STUDY APPRAISAL AND SYNTHESIS METHODS

Two authors independently screened each abstract, conducted full-text review, assessed study quality, and extracted information. A third author resolved disagreements.

RESULTS

Of 371 articles identified, 7 were included for the review. Outcomes of interest were asthma symptom-free days, asthma symptom frequency, quality of life, health care utilization, school absences, and spirometry. Four of 7 studies reported significant increases in symptom-free days and/or decrease in symptom frequency. Five of 6 reported increases in at least one quality-of-life metric, 2 of 7 reported a decrease in at least 1 health care utilization metric, 1 of 3 showed reductions in school absences, and 1 of 2 reported improvements in spirometry measures.

LIMITATIONS

Variability in intervention designs and outcome measures make comparisons and quantitative analyses across studies difficult. Only 2 of 7 studies were randomized controlled trials.

CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS

High-quality evidence supporting the use of school-based telemedicine programs to improve patient outcomes is limited. While available evidence suggests benefit, only 2 comparative trials were identified, and the contribution of telemedicine to these studies' results is unclear.

Estimating age-specific influenza-associated asthma morbidity in Ontario, Canada

BACKGROUND

There is a need to quantify the potential benefits of influenza-focused interventions in reducing asthma morbidity at a population level. This study aims to estimate age-specific annual excess asthma morbidity attributable to influenza in Ontario, Canada.

METHODS

Weekly counts of hospitalizations, emergency department (ED) visits and outpatient physician office visits for asthma were obtained from health administrative data in Ontario from 2010 to 2015, for ages 0-14, 15-59 and 60+. Asthma morbidity was modelled as a function of influenza A and B activity using linear regression, controlling for seasonal and long-term trend, mean temperature and respiratory syncytial virus. Excess asthma morbidity attributable to influenza was calculated as the difference between full model predictions and model predictions with influenza A and B variables set to 0.

RESULTS

Annually, influenza was associated with the following rates of excess asthma morbidity, per 100,000 people with prevalent asthma: 12.5 hospitalizations for ages 15-59 (95% confidence interval (CI): 1.1-23.5); 35.7 hospitalizations for ages 60+ (95% CI: 3.3-67.1); 114.1 ED visits for ages 15-59 (95% CI: 46.9-181.6); 154.6 ED visits for ages 60+ (95% CI: 86.7-223.3); and 1025.7 outpatient physician office visits for ages 60+ (95% CI: 79.0-1877.3).

CONCLUSIONS

Influenza was associated with excess asthma hospitalizations and ED visits for ages 15-59 and 60+ and outpatient physician office visits for ages 60+. Individuals with asthma aged 15-59 and 60+ might be important targets for influenza-focused interventions, to reduce asthma morbidity at the population level.

Asthma progression and mortality: the role of inhaled corticosteroids

Overall, asthma mortality rates have declined dramatically in the last 30 years, due to improved diagnosis and to better treatment, particularly in the 1990s following the more widespread use of inhaled corticosteroids (ICSs). The impact of ICS on other long-term outcomes, such as lung function decline, is less certain, in part because the factors associated with these outcomes are incompletely understood. The purpose of this review is to evaluate the effect of pharmacological interventions, particularly ICS, on asthma progression and mortality. Furthermore, we review the potential mechanisms of action of pharmacotherapy on asthma progression and mortality, the effects of ICS on long-term changes in lung function, and the role of ICS in various asthma phenotypes.Overall, there is compelling evidence of the value of ICS in improving asthma control, as measured by improved symptoms, pulmonary function and reduced exacerbations. There is, however, less convincing evidence that ICS prevents the decline in pulmonary function that occurs in some, although not all, patients with asthma. Severe exacerbations are associated with a more rapid decline in pulmonary function, and by reducing the risk of severe exacerbations, it is likely that ICS will, at least partially, prevent this decline. Studies using administrative databases also support an important role for ICS in reducing asthma mortality, but the fact that asthma mortality is, fortunately, an uncommon event makes it highly improbable that this will be demonstrated in prospective trials.

Seasonal variation in asthma exacerbations in the AUSTRI and VESTRI studies

Seasonal peaks in asthma exacerbations are well described, as is the age-dependent nature of the magnitude of these peaks [1]. Children with asthma experience seasonal peaks in exacerbation frequency, which vary according to geographical location and climate [1–3]. Previous studies have examined the effect of season on the efficacy of pharmacological interventions. The anti-immunoglobulin-E monoclonal antibody omalizumab showed an increase in treatment benefits compared with placebo in the autumn and spring versus summer months in children, adolescents and young adults with allergic asthma in the USA [4]. In contrast, the anti-interleukin-5 monoclonal antibody mepolizumab showed no effect of seasonal differences in adolescents and adults with severe eosinophilic asthma [5].

Seasonal variation in the benefit of LABA/ICS versus ICS on asthma exacerbation rate is observed in children.http://ow.ly/pcZF30o8hHk

Asthma exacerbation prediction: recent insights

PURPOSE OF REVIEW

Asthma attacks are frequent in children with asthma and can lead to significant adverse outcomes including time off school, hospital admission and death. Identifying children at risk of an asthma attack affords the opportunity to prevent attacks and improve outcomes.

RECENT FINDINGS

Clinical features, patient behaviours and characteristics, physiological factors, environmental data and biomarkers are all associated with asthma attacks and can be used in asthma exacerbation prediction models. Recent studies have better characterized children at risk of an attack: history of a severe exacerbation in the previous 12 months, poor adherence and current poor control are important features which should alert healthcare professionals to the need for remedial action. There is increasing interest in the use of biomarkers. A number of novel biomarkers, including patterns of volatile organic compounds in exhaled breath, show promise. Biomarkers are likely to be of greatest utility if measured frequently and combined with other measures. To date, most prediction models are based on epidemiological data and population-based risk. The use of digital technology affords the opportunity to collect large amounts of real-time data, including clinical and physiological measurements and combine these with environmental data to develop personal risk scores. These developments need to be matched by changes in clinical guidelines away from a focus on current asthma control and stepwise escalation in drug therapy towards inclusion of personal risk scores and tailored management strategies including nonpharmacological approaches.

SUMMARY

There have been significant steps towards personalized prediction models of asthma attacks. The utility of such models needs to be tested in the ability not only to predict attacks but also to reduce them.

Chronic lifestyle diseases display seasonal sensitive comorbid trend in human population evidence from Google Trends

Seasonal and human physiological changes are important factors in the development of many diseases. But, the study of genuine seasonal impact on these diseases is difficult to measure due to many other environment and lifestyle factors which directly affect these diseases. However, several clinical studies have been conducted in different parts of the world, and it has clearly indicated that certain groups of population are highly subjected to seasonal changes, and their maladaptation can possibly lead to several disorders/diseases. Thus, it is crucial to study the significant seasonal sensitive diseases spread across the human population. To narrow down these disorders/diseases, the study hypothesized that high altitude (HA) associated diseases and disorders are of the strong variants of seasonal physiologic changes. It is because, HA is the only geographical condition for which humans can develop very efficient physiological adaptation mechanism called acclimatization. To study this hypothesis, PubMed was used to collect the HA associated symptoms and disorders. Disease Ontology based semantic similarity network (DSN) and disease-drug networks were constructed to narrow down the benchmark diseases and disorders of HA. The DSN which was further subjected to different community structure analysis uncovered the highly associated or possible comorbid diseases of HA. The predicted 12 lifestyle diseases were assumed to be “seasonal (sensitive) comorbid lifestyle diseases (SCLD)”. A time series analyses on Google Search data of the world from 2004–2016 was conducted to investigate whether the 12 lifestyle diseases have seasonal patterns. Because, the trends were sensitive to the term used as benchmark; the temporal relationships among the 12 disease search volumes and their temporal sequences similarity by dynamic time warping analyses was used to predict the comorbid diseases. Among the 12 lifestyle diseases, the study provides an indirect evidence in the existence of severe seasonal comorbidity among hypertension, obesity, asthma and fibrosis diseases, which is widespread in the world population. Thus, the present study has successfully addressed this issue by predicting the SCLD, and indirectly verified them among the world population using Google Search Trend. Furthermore, based on the SCLD seasonal trend, the study also classified them as severe, moderate, and mild. Interestingly, seasonal trends of the severe seasonal comorbid diseases displayed an inverse pattern between USA (Northern hemisphere) and New Zealand (Southern hemisphere). Further, knowledge in the so called “seasonal sensitive populations” physiological response to seasonal triggers such as winter, summer, spring, and autumn become crucial to modulate disease incidence, disease course, or clinical prevention.

Nasopharyngeal isolates and their clinical impact on young children with asthma: a pilot study

Introduction

Respiratory infections have significant effects on childhood asthma. Viral respiratory infections, such as rhinovirus and respiratory syncytial virus are likely to be important in the development and exacerbation of asthma. In this study, we investigated the nasopharyngeal colonization in children with asthma to determine the prevalence of pathogens and their contribution to respiratory symptoms and airway resistance during winter.

Methods

From December 2016 to March 2017, 50 nasopharyngeal specimens were collected from 18 patients (age, 5.0±1.1 years) with asthma and 9 specimens from 9 control children (age, 4.9±1.0 years). Samples were tested for 19 viruses and 7 bacteria, using multiplex real-time PCR. Respiratory disease markers included the Global Asthma Network Questionnaire, the Common-Cold Questionnaire, the Global Initiative for Asthma assessment of asthma control, and the airway resistance at 5 Hz by forced-oscillation technique.

Results

The most commonly isolated organisms in both groups (patients and controls) were Streptococcus pneumoniae, Haemophilus influenzae, and rhinovirus. Most patients had multiple isolates (median, 3.5; range, 1-5), which changed during the study period. Types of isolates were 4 bacteria (S. pneumoniae, H. influenzae, Bordetella pertussis, and Bordetella parapertussis) and 6 viruses (rhinovirus, enterovirus, metapneumovirus, adenovirus, coronaviruses, and parainfluenza viruses). Similar isolates, including influenza A-H3 virus and bocavirus, were detected in the controls. Of the 9 patients with "wheezing disturbing sleep ≥1 per week", 6 had rhinovirus, 2 coronaviruses, and 1 no detectable viruses. Patients with mild common cold symptoms had significantly higher airway resistance at 5 Hz z-score (P=0.025).

Conclusion

Multiple respiratory pathogens were isolated from many patients with asthma, which appeared to contribute to disease symptoms and airway resistance. Minimizing children's exposure to respiratory pathogens might be beneficial, especially during winter.

Contribution of repeated infections in asthma persistence from preschool to school age: Design and characteristics of the PreDicta cohort

BACKGROUND

The PreDicta cohort was designed to prospectively evaluate wheeze/asthma persistence in preschoolers in association with viral/microbial exposures and immunological responses. We present the cohort design and demographic/disease characteristics and evaluate unsupervised and predefined phenotypic subgroups at inclusion.

METHODS

PreDicta is a 2-year prospective study conducted in five European regions, including children 4-6 years with a diagnosis of asthma as cases and healthy age-matched controls. At baseline, detailed information on demographics, asthma and allergy-related disease activity, exposures, and lifestyle were recorded. Lung function, airway inflammation, and immune responses were also assessed. Power analysis confirmed that the cohort is adequate to answer the initial hypothesis.

RESULTS

A total of 167 asthmatic children (102 males) and 66 healthy controls (30 males) were included. Groups were homogeneous in respect to most baseline characteristics, with the exception of male gender in cases (61%) and exposure to tobacco smoke. Comorbidities and number and duration of infections were significantly higher in asthmatics than controls. 55.7% of asthmatic children had at least one positive skin prick test to aeroallergens (controls: 33.3%, P = .002). Spirometric and exhaled nitric oxide values were within normal limits; only baseline FEV_0.5 and FEV₁ reversibility values were significantly different between groups. Viral infections were the most common triggers (89.2%) independent of severity, control, or atopy; however, overlapping phenotypes were also common. Severity and control clustered together in an unsupervised analysis, separating moderate from mild disease.

CONCLUSIONS

The PreDicta cohort presented no differences in non-asthma related measures; however, it is well balanced regarding key phenotypic characteristics representative of "preschool asthma".

Asthma among adult patients presenting with dyspnea to the emergency department: An observational study

INTRODUCTION

Shortness of breath is a common presenting symptom to the emergency department (ED) that can arise from a myriad of possible diagnoses. Asthma is one of the major causes.

OBJECTIVE

The aim of this study was to describe the demographic features, clinical characteristics, management and outcomes of adults with an ED diagnosis of asthma who presented to an ED in the Asia Pacific region with a principal symptom of dyspnea.

METHODS

Planned sub-study of patients with an ED diagnosis of asthma identified in the Asia, Australia and New Zealand Dyspnoea in Emergency Departments (AANZDEM) study. AANZDEM was a prospective cohort study conducted in 46 EDs in Australia, New Zealand, Singapore, Hong Kong and Malaysia over three 72 hour periods in May, August and October 2014. Primary outcomes were patient epidemiology, clinical features, treatment and outcomes (hospital length of stay (LOS) and mortality).

RESULTS

Of the 3044 patients with dyspnea, 387 (12.7%) patients had an ED diagnosis of asthma. The median age was 45 years, 60.1% were female, 16.1% were active or recent smokers and 30.4% arrived by ambulance. Inhaled bronchodilator therapy was initiated in 88.1% of patients, and 66.9% received both inhaled bronchodilators and systemic corticosteroids. After treatment in the ED, 65.4% were discharged. No death was reported.

CONCLUSION

Asthma is common among patients presenting with a principal symptom of dyspnea in the ED of the Asia Pacific region. There was a suboptimal adherence to international guidelines on investigations and treatments of acute asthma exacerbations presenting an opportunity to improve the efficiency of care.

Integrating Smart Health in the US Health Care System: Infodemiology Study of Asthma Monitoring in the Google Era

BACKGROUND

With the internet's penetration and use constantly expanding, this vast amount of information can be employed in order to better assess issues in the US health care system. Google Trends, a popular tool in big data analytics, has been widely used in the past to examine interest in various medical and health-related topics and has shown great potential in forecastings, predictions, and nowcastings. As empirical relationships between online queries and human behavior have been shown to exist, a new opportunity to explore the behavior toward asthma-a common respiratory disease-is present.

OBJECTIVE

This study aimed at forecasting the online behavior toward asthma and examined the correlations between queries and reported cases in order to explore the possibility of nowcasting asthma prevalence in the United States using online search traffic data.

METHODS

Applying Holt-Winters exponential smoothing to Google Trends time series from 2004 to 2015 for the term "asthma," forecasts for online queries at state and national levels are estimated from 2016 to 2020 and validated against available Google query data from January 2016 to June 2017. Correlations among yearly Google queries and between Google queries and reported asthma cases are examined.

RESULTS

Our analysis shows that search queries exhibit seasonality within each year and the relationships between each 2 years' queries are statistically significant (P<.05). Estimated forecasting models for a 5-year period (2016 through 2020) for Google queries are robust and validated against available data from January 2016 to June 2017. Significant correlations were found between (1) online queries and National Health Interview Survey lifetime asthma (r=-.82, P=.001) and current asthma (r=-.77, P=.004) rates from 2004 to 2015 and (2) between online queries and Behavioral Risk Factor Surveillance System lifetime (r=-.78, P=.003) and current asthma (r=-.79, P=.002) rates from 2004 to 2014. The correlations are negative, but lag analysis to identify the period of response cannot be employed until short-interval data on asthma prevalence are made available.

CONCLUSIONS

Online behavior toward asthma can be accurately predicted, and significant correlations between online queries and reported cases exist. This method of forecasting Google queries can be used by health care officials to nowcast asthma prevalence by city, state, or nationally, subject to future availability of daily, weekly, or monthly data on reported cases. This method could therefore be used for improved monitoring and assessment of the needs surrounding the current population of patients with asthma.

Interventions for autumn exacerbations of asthma in children

BACKGROUND

Asthma exacerbations in school-aged children peak in autumn, shortly after children return to school following the summer holiday. This might reflect a combination of risk factors, including poor treatment adherence, increased allergen and viral exposure, and altered immune tolerance. Since this peak is predictable, interventions targeting modifiable risk factors might reduce exacerbation-associated morbidity and strain upon health resources. The peak occurs in September in the Northern Hemisphere and in February in the Southern Hemisphere.

OBJECTIVES

To assess the effects of pharmacotherapy and behavioural interventions enacted in anticipation of school return during autumn that are designed to reduce asthma exacerbations in children during this period.

SEARCH METHODS

We searched the Cochrane Airways Group Trials Register, ClinicalTrials.gov, the World Health Organization International Clinical Trials Registry Platform, reference lists of primary studies and existing reviews, and manufacturers' trial registries (Merck, Novartis and Ono Parmaceuticals). We searched databases from their inception to 1 December 2017, and imposed no restriction on language of publication.

SELECTION CRITERIA

We included all randomised controlled trials comparing interventions aimed specifically at reducing autumn exacerbations with usual care, (no systematic change in management in preparation for school return). We included studies providing data on children aged 18 years or younger.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Two review authors independently screened records identified by the search and then extracted data and assessed bias for trials meeting the inclusion criteria. A third review author checked for accuracy and mediated consensus on disagreements. The primary outcome was proportion of children experiencing one or more asthma exacerbations requiring hospitalisation or oral corticosteroids during the autumn period.

MAIN RESULTS

Our searches returned 546 trials, of which five met our inclusion criteria. These studies randomised 14,252 children to receive either an intervention or usual care. All studies were conducted in the Northern Hemisphere. Three interventions used a leukotriene receptor antagonist, one used omalizumab or a boost of inhaled corticosteroids, and the largest study, (12,179 children), used a medication reminder letter. Whilst the risk of bias within individual studies was generally low, we downgraded the evidence quality due to imprecision associated with low participant numbers, poor consistency between studies, and indirect outcome ascertainment.A US study of 513 children with mild/severe asthma and allergic sensitisation was the only study to provide data for our primary outcome. In this study, the proportion of participants experiencing an exacerbation requiring oral corticosteroids or hospital admission in the 90 days after school return was significantly reduced to 11.3% in those receiving omalizumab compared to 21.0% in those receiving placebo (odds ratio 0.48, 95% confidence interval 0.25 to 0.92, moderate-quality evidence). The remaining studies used alternative exacerbation definitions. When data from two leukotriene receptor antagonist studies with comparable outcomes were combined in a random-effects model, there was no evidence of an effect upon exacerbations. There was no evidence that a seasonal medication reminder letter decreased unscheduled contacts for a respiratory diagnosis between September and December.Four studies recorded adverse events. There was no evidence that the proportion of participants experiencing at least one adverse event differed between intervention and usual care groups. Lack of data prevented planned subgroup and sensitivity analyses.

AUTHORS' CONCLUSIONS

Seasonal omalizumab treatment from four to six weeks before school return might reduce autumn asthma exacerbations. We found no evidence that this strategy is associated with increased adverse effects other than injection site pain, but it is costly. There were no data upon which to judge the effect of this or other seasonal interventions on asthma control, quality of life, or asthma-related death. In future studies definitions of exacerbations should be provided, and standardised where possible. To investigate possible differential effects according to subgroup, participants in future trials should be well characterised with respect to baseline asthma severity and exacerbation history in addition to age and gender.

Acute Asthma in the Pediatric Emergency Department: Infections Are the Main Triggers of Exacerbations

Background

Asthma exacerbations are a common reason for Emergency Department (ED) visits in children.

Aim

To analyze differences among age groups in terms of triggering factors and seasonality and to identify those with higher risk of severe exacerbations.

Methods

We retrospectively revised the files of children admitted for acute asthma in 2016 in our Pediatric ED.

Results

Visits for acute asthma were 603/23197 (2.6%). 76% of the patients were <6 years old and 24% ≥6. Infections were the main trigger of exacerbations in both groups; 33% of the school-aged children had a triggering allergic condition (versus 3% in <6 years; p < .01). 191 patients had a previous history of asthma; among them, 95 were ≥6 years, 67% of whom were not using any controller medication, showing a higher risk of a moderate-to-severe exacerbation than those under long-term therapy (p < .01). Exacerbations peaked in autumn and winter in preschoolers and in spring and early autumn in the school-aged children.

Conclusions

Infections are the main trigger of acute asthma in children of any age, followed by allergy in the school-aged children. Efforts for an improved management of patients affected by chronic asthma might go through individualized action plans and possibly vaccinations and allergen-avoidance measures.

Seasonal Cycle and Relationship of Seasonal Rhino- and Influenza Virus Epidemics With Episodes of Asthma Exacerbation in Different Age Groups

Purpose

Seasonal variations in asthma exacerbation (AE) are associated with respiratory virus outbreaks and the return of children to school after vacation. This study aims to elucidate the period, phase, and amplitude of seasonal cycles of AE in 5 different age groups with regard to rhino- and influenza virus epidemics in Korea.

Methods

The number of daily emergency department (ED) visits for AE in all age groups of Korea and the nationwide weekly incidence of rhino- and influenza virus, were obtained for 2008-2012. Fourier regression was used to model rhythmicity, and the Cosinor method was used to determine the amplitude and phase of the cycles in each age group. The cross-correlation function (CCF) between AE and the rhino- and influenza virus epidemics was also calculated.

Results

There were 157,559 events of AE (0.62 events/1,000 individuals/year) during the study period. There were spring and fall peaks of AE in children and adults, but only 1 winter peak in the elderly. The amplitude of the AE peak in infants was higher in spring than in fall (9.16 vs 3.04, P<0.010), and the fall peak was approximately 1 month later in infants than in school children (October 11 vs November 13, P<0.010). The association between AE and rhinovirus was greatest in school children (rho=0.331), and the association between AE and influenza virus was greatest in those aged ≥60 years (rho=0.682).

Conclusions

The rhythmicity, amplitude, and phase of the annual cycle of AE differed among different age groups. The patterns of AE were related to the annual rhino- and influenza virus epidemics.