Asthma Admissions In Children Research Articles

Short-Term Nitrogen Dioxide Exposure and Emergency Hospital Admissions for Asthma in Children: A Case-Crossover Analysis in England.

There is an increasing body of evidence associating short-term ambient nitrogen dioxide (NO2) exposure with asthma-related hospital admissions in children. However, most studies have relied on temporally resolved exposure information, potentially ignoring the spatial variability of NO2. We aimed to investigate how daily NO2 estimates from a highly resolved spatio-temporal model are associated with the risk of emergency hospital admission for asthma in children in England. We conducted a time-stratified case-crossover study including 111,766 emergency hospital admissions for asthma in children (aged 0-14 years) between 1st January 2011 and 31st December 2015 in England. Daily NO2 levels were predicted at the patients' place of residence using spatio-temporal models by combining land use data and chemical transport model estimates. Conditional logistic regression models were used to obtain the odds ratios (OR) and confidence intervals (CI) after adjusting for temperature, relative humidity, bank holidays, and influenza rates. The effect modifications by age, sex, season, area-level income deprivation, and region were explored in stratified analyses. For each 10 µg/m³ increase in NO2 exposure, we observed an 8% increase in asthma-related emergency admissions using a five-day moving NO2 average (mean lag 0-4) (OR 1.08, 95% CI 1.06-1.10). In the stratified analysis, we found larger effect sizes for male (OR 1.10, 95% CI 1.07-1.12) and during the cold season (OR 1.10, 95% CI 1.08-1.12). The effect estimates varied slightly by age group, area-level income deprivation, and region. Short-term exposure to NO2 was significantly associated with an increased risk of asthma emergency admissions among children in England. Future guidance and policies need to consider reflecting certain proven modifications, such as using season-specific countermeasures for air pollution control, to protect the at-risk population.

Increased Risk of Hospital Admission for Asthma in Children From Short-Term Exposure to Air Pollution: Case-Crossover Evidence From Northern China

Background: Previous studies suggested that exposure to air pollution could increase risk of asthma attacks in children. The aim of this study is to investigate the short-term effects of exposure to ambient air pollution on asthma hospital admissions in children in Beijing, a city with serious air pollution and high-quality medical care at the same time.Methods: We collected hospital admission data of asthma patients aged ≤ 18 years old from 56 hospitals from 2013 to 2016 in Beijing, China. Time-stratified case-crossover design and conditional Poisson regression were applied to explore the association between risk of asthma admission in children and the daily concentration of six air pollutants [particulate matter ≤ 2.5 μm (PM2.5), particulate matter ≤ 10 μm (PM10), sulfur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO), and ozone (O3)], adjusting for meteorological factors and other pollutants. Additionally, stratified analyses were performed by age, gender, and season.Results: In the single-pollutant models, higher levels of PM2.5, SO2, and NO2 were significantly associated with increased risk of hospital admission for asthma in children. The strongest effect was observed in NO2 at lag06 (RR = 1.25, 95%CI: 1.06-1.48), followed by SO2 at lag05 (RR = 1.17, 95%CI: 1.05–1.31). The robustness of effects of SO2 and NO2 were shown in two-pollutant models. Stratified analyses further indicated that pre-school children (aged ≤ 6 years) were more susceptible to SO2. The effects of SO2 were stronger in the cold season, while the effects of NO2 were stronger in the warm season. No significant sex-specific differences were observed.Conclusions: These results suggested that high levels of air pollution had an adverse effect on childhood asthma, even in a region with high-quality healthcare. Therefore, it will be significant to decrease hospital admissions for asthma in children by controlling air pollution emission and avoiding exposure to air pollution.

Impacts of exposure to humidex on the risk of childhood asthma hospitalizations in Hefei, China: Effect modification by gender and age.

With global climate change, there is growing concern about the effects of temperature changes on childhood asthma. However, current research only focuses on the effects of temperature, while ignoring the adverse effects of humidity on children. Our study aimed to quantify the impact of humidex on childhood asthma hospitalizations, which combined temperature and humidity, and further to assess how the effect is modified by individual-factors, such as age and gender. Poisson generalized linear models combined with distributed lag nonlinear models were used to estimate the association between daily childhood asthma hospitalizations and humidex from 2013 to 2016. Air pollutions (CO, O3, and NO2) and wind velocity were modelled simultaneously using DLNM, as well as day of week, seasonality and long-term trend. Low humidex was associated with an increased risk of admissions for asthma in children. The adverse effect appeared on the 4th day, with the RR of 1.045 (95%CI: 1.007-1.084) and lasted until the 7th day (RR: 1.045, 95%CI: 1.006-1.085). Compared with the male, there was an immediate effect on female exposed to low humidex. And the female seems to be more sensitive to low humidex. Besides, the significant effects of humidex on children asthma were detected in the children with preschool and school-age, whereas not for the subgroup of infants. And the school-age children are most sensitive to low humidex. Low humidex was associated with the increased risk of admissions for childhood asthma in Hefei. Children suffering from asthma should avoid exposure to the low humidex environment, especially in female and school-age children. In addition, the index of humidex was more significant for disease prevention and public health than the average temperature. These findings may provide epidemiology evidence for formulating precaution guidelines to reduce the risk of childhood asthma hospitalizations.

The short-term association between air pollution and childhood asthma hospital admissions in urban areas of Hefei City in China: A time-series study

BackgroundThe impacts of air pollution on asthma attacks have become a hotspot. Previous studies mainly focused on the developed countries or cities. There have been very limited studies in less-developed region to quantify the effects of air pollutants on asthma admissions in children. This study aims to assess the short-term impact of air pollutants on asthma hospital admissions for children in Hefei, China. MethodsPoisson generalized linear regression combined with distributed lag non-linear model (DLNM) were applied to investigate the effects of air pollutants on daily childhood hospital admissions of asthma from 2015 to 2016, controlling for meteorological factors. Subgroup analyses by sex and age were performed. ResultsThere were a total of 17,227 asthma admissions during 2015–2016. We found positive correlations between childhood asthma hospital visits and concentrations of NO2, O3, PM10 and PM2.5. Significantly, NO2 exhibited robust positive correlations with cumulative effects 1.551 (95% CI: 1.306–1.841, lag0–3 days) in single-pollutant model and 1.580 (95% CI: 1.315–1.899, lag0–3 days) in multiple-pollutant model. ConclusionsAir pollutants had adverse effects on childhood asthma. NO2 presented the greatest effect, followed by PM2.5. Results will be important for health authority and guardians to realize the severity of air pollution on the increased risk of asthma, so as to develop relevant strategies and health interventions to meet the challenges of childhood asthma and reduce air pollution.

High ambient levels of grass, weed and other pollen are associated with asthma admissions in children and adolescents: A large 5‐year case‐crossover study

Pollen is an important aeroallergen that triggers asthma exacerbations in children, but we know little about the impact of different pollen types in cities with varying climatic conditions and pollen seasons. We aimed to assess the role of ambient level of different types of pollen on a large time series of child and adolescent asthma hospitalizations in Sydney, Australia. Childhood asthma hospitalization and the daily ambient pollen concentrations of different species were collected in South-West Sydney. With a bidirectional case-crossover design, we fitted conditional logistic regression models to measure the associations between instantaneous and up to 3days lagged effects of pollen concentrations on asthma hospitalizations after controlling for potential confounders and testing for interactions. A total of 2098 children, more boys (59.7%) and 2-5years old (62.6%), were hospitalized due to asthma. The geometric mean concentration of Cupressus, 7.88 [5.02] grains/m3 , was the highest during the study period. The increase from 75th to 90th percentile of grass (OR=1.037, 95% CI 1.005-1.070), weed other than Plantago species (OR=1.053, 95% CI 1.009-1.098) and unclassified pollen (OR=1.034, 95% CI 1.010-1.058) were significantly associated with the odds of asthma hospitalizations. Boys were at greater risk of asthma exacerbations associated with grass (OR=1.046, 95% CI 1.003-1.090) and unclassified pollen (OR=1.041, 95% CI 1.010-1.073). There was evidence of effect modification by age groups for Cupressus, conifer, total tree and total pollen. Although boys are more vulnerable to grass pollen, weed, and other pollen are also important triggers of asthma exacerbations in all children and adolescents. These findings are important for urban green space planning and the development of pollen monitoring systems for families with children at risk of asthma exacerbations during peak pollen seasons.

Les hospitalisations pour asthme chez l’enfant en France, 2002–2010

Most hospital admissions for asthma exacerbation are avoidable with adequate disease management. The objective of this study was to describe admissions for asthma in children in France using data from the French nationwide hospital database. We selected admissions having either a main diagnosis of asthma or a main diagnosis of acute respiratory failure (ARF) with asthma as an associated diagnosis, occurring in children (age<15years) between 2002 and 2010 in France (excluding French Guyana). In 2010, 35,004asthma admissions and 1381cases of asthma-related ARF were recorded (crude admission rate, 30.1/10,000 children); the mean length of stay was 2days. The in-hospital lethality rate ranged from 0.01% to 0.03% depending on the year. The annual age-standardized admission rate increased between 2002 and 2010 (+2.5% per year on average in metropolitan France). In 2010, 11.8% of children admitted for asthma or asthma-related ARF were readmitted for asthma or asthma-related ARF at least once within the same calendar year, and 1.3% were readmitted within the week following admission. The proportion of children aged less than 5 years who were readmitted within the same calendar year increased between 2002 and 2010. The increase in admission and readmission rates indicates non-optimal management of asthma in children in France.

Paediatric asthma hospital utilization varies by demographic factors and area socio-economic status

Associations of emergency department (ED) visits and hospital admissions for asthma in children with demographics and area socio-economic status (SES) were examined to evaluate long-term trends and identify vulnerable populations. Retrospective population-based trend and cross-sectional analyses. Asthma hospital admissions (2000-2007) and ED visits (2005-2007) for children aged 0-14 years living in Orange County, California were linked with zip-code-level SES data (2000 US Census). Annual population estimates were obtained to calculate age-specific admissions and ED visit rates. Average annual percentage changes (AAPC) were calculated with joinpoint analyses. The risks of ED visits and hospital admissions were estimated from SES indicators with negative binomial regression. Rates of asthma hospital admissions and ED visits were highest among children aged 0-4 years, males and African Americans, and lowest among Asian/Pacific Islanders. African Americans and Hispanics/Latinos were more likely to be uninsured. Asthma admissions decreased significantly for all age groups over the study period. The greatest declines per 100,000 were among children aged 0-4 years (AAPC: -15.3%, 95% confidence interval -17.0% to -13.4%). Rates of hospital admissions and ED visits were significantly higher in low-SES groups. Hospital admission rates were 30-60% higher and ED visits were 80-90% higher in zip codes in the lowest tertile of median household income compared with the highest tertile of median household income. Paediatric asthma hospitalizations and ED visit rates are declining in Orange County. However, certain groups are disproportionately affected, including those living in areas with low SES. This information will help in targeting intervention strategies to children at highest risk for severe asthma episodes.

Coarse and fine particles but not ultrafine particles in urban air trigger hospital admission for asthma in children

BackgroundShort-term exposure to air pollution can trigger hospital admissions for asthma in children, but it is not known which components of air pollution are most important. There are no available...

News and Notes

News and Notes

Hospitalizações por causas respiratórias e cardiovasculares associadas à contaminação atmosférica no Município de São Paulo, Brasil

The recognition that current air pollution levels cause harmful health effects makes the definition of the air quality regulatory process imperative. This study examines the association between exposure to air pollution and hospital admissions in the city of São Paulo, aiming to support the development of measures to reduce such health risks. The authors conducted an ecological time series study of hospital admissions for respiratory and cardiovascular diseases in children and the elderly in relation to daily air pollution levels, using generalized additive Poisson regression models. All air pollutants except ozone showed a statistically significant association with admissions for respiratory and cardiovascular diseases. An increase of 10 microg/m3 in fine particulate matter was associated with a 4.6% increase in asthma admissions in children and a 4.3% increase in admissions for chronic obstructive pulmonary disease and 1.5% for ischemic heart disease in the elderly. These associations are consistent with a large body of literature in this area and indicate that the current air pollution levels in São Paulo have an important negative impact on the population's health.

Childhood asthma and return to school in Sydney, Australia

To describe the seasonal pattern of hospital admissions for childhood asthma in Sydney, Australia and investigate the relationship between these admissions and time of return to school. Time-series analysis of daily hospital admissions for childhood asthma in Sydney from 1994 to 2000. We defined the time series of all asthma-related hospital admissions in Sydney between 1994 and 2000 for age groups 1-4 and 5-14 years. We analysed the time series for each age group using a generalized additive model with a log-link function, an offset term and quasi-likelihood estimation. Daily admissions were modelled using penalised regression splines adjusting for long term trends, school terms and holidays, weekday and influenza epidemics. After adjusting for potential confounding, the risk of asthma admission increased to a peak between 2 and 4 weeks after the first day of school in each term and varied between 1.5 and 3 times the risk prior to return to school for both age groups. The largest increase in asthma risk occurring in term one after the long summer holiday. The increase in admission risk began soon after the first day of school of each term for school age children 5-14 years, but not in pre-school age children 1-4 years. Returning to school after term holidays is strongly associated with increased risk of hospital admissions for asthma in children, especially following the long summer holiday. Preventive measures focused on return to school have the potential to substantially decrease admissions for asthma in children.

Risk factors for hospital admission for asthma from childhood to young adulthood: a longitudinal population study.

Predictors of hospital admissions for asthma in children and young adults in a general population are not well defined, because most studies have used selected subpopulations. The purpose of this investigation was to determine risk factors for single and multiple hospital admissions for asthma. The members of a population-based, unselected birth cohort of 1037 New Zealanders answered questionnaires and underwent lung function, airway responsiveness, and allergy testing on 7 occasions to the age of 26 years. Among the 766 study members (74% of the cohort) who reported wheezing symptoms ever by the age of 26 years, 136 hospitalizations were reported by 62 individuals (8.3% of those at risk, 6.2% of the total cohort). Only 55 of these 136 admissions involved children less than 9 years of age; admissions continued to occur between the ages of 9 and 18 years (40 admissions) and at >18 years (41 admissions). Those admitted were predominantly male, had earlier ages of onset of symptoms, were more atopic, and had more airway hyperresponsiveness to methacholine than those not admitted. Frequent symptoms and low lung function were evident among the 45 study members with single admissions and even more evident among the 17 study members with multiple (2-10) admissions. A surprisingly large fraction of this unselected population experienced hospitalization for asthma during the 26-year follow-up, many being admitted in later childhood, adolescence, and early adulthood. Clinical characteristics and markers of severity, including frequent respiratory symptoms, airway hyperresponsiveness, atopy, and low lung function, identify those at high risk for hospitalization for asthma, particularly with respect to multiple admissions.

Proximity to coke works and hospital admissions for respiratory and cardiovascular disease in England and Wales

BACKGROUNDThe incidence of hospital admissions for respiratory and cardiovascular diseases in areas close to operating coke works in England and Wales was investigated.METHODSA small area study using distance from source...

Personal exposure to nitrogen dioxide and risk of airflow obstruction in asthmatic children with upper respiratory infection

BACKGROUNDSeveral studies have linked air pollution by nitrogen dioxide (NO2) with increased hospital admissions for asthma in children. Exacerbations of asthma in children are often precipitated by upper respiratory infections....

Asthma and respiratory syncytial virus infection in infancy: is there a link?

Asthma and respiratory syncytial virus infection in infancy: is there a link?

The relationship between upper respiratory infections and hospital admissions for asthma: a time-trend analysis.

We have shown that viruses are associated with 80 to 85% of asthma exacerbations in school-age children in the community. We hypothesize that viral infections are also associated with severe attacks of asthma precipitating hospital admissions. To investigate this, we conducted a time-trend analysis, comparing the seasonal patterns of respiratory infections and hospital admissions for asthma in adults and children. During a 1-yr study in the Southampton area of the United Kingdom, 108 school-age children monitored upper and lower respiratory symptoms and took peak expiratory flow rate (PEFR) recordings. From children reporting a symptomatic episode or a decrease in PEFR, samples were taken for detection of viruses and atypical bacteria. A total of 232 respiratory viruses and four atypical bacteria were detected. The half-monthly rates of upper respiratory infection were compared with the half-monthly rates for hospital admissions for asthma (International Classification of Diseases [ICD] code 493) for the same time period for the hospitals serving the areas from which the cohort of schoolchildren was drawn. The relationships of upper respiratory infections and hospital admissions for asthma with school attendance were studied. Strong correlations were found between the seasonal patterns of upper respiratory infections and hospital admissions for asthma (r = 0.72; p < 0.0001). This relationship was stronger for pediatric (r = 0.68; p < 0.0001) than for adult admissions (r = 0.53; p < 0.01). Upper respiratory infections and admissions for asthma were more frequent during periods of school attendance (87% of pediatric and 84% of total admissions), than during school holiday periods (p < 0.001). These relationships remained significant when allowance was made for linear trend and seasonal variation using multiple regression analysis (p < 0.01). Not surprisingly, school attendance, because it is a major factor in respiratory virus transmission, was found to be a major confounding variable in children. This study demonstrates that upper respiratory viral infections are strongly associated in time with hospital admissions for asthma in children and adults. Rhinoviruses were the major pathogen implicated, and the majority of viral infections and asthma admissions occurred during school attendance.

Management of asthma

Despite recent advances in the understanding and treatment of asthma, it remains an important cause of illness in children. It causes recurrent absence from school, restriction of activities, and much anxiety and unhappiness for children and parents. Hospital admissions for asthma in children in the O-4 years age group increased almost seven-fold between 1970 and 1986 and admissions for children in the 5-14 age group tripled.’ Asthma is responsible for a fifth of all admissions to paediatric wards in the 5-14 age group.’ Consultations with General Practitioners for asthma have doubled in the last decade. Whether these changes represent a real increase in prevalence, or whether they simply reflect changes in referral, management, or diagnosis, is unclear.2 What is clear, is that despite having safe, effective treatment there is no decrease in asthma morbidity. Why is this so?