The BREATHE Study: Bronchiolitis Recovery and Use of HEPA Filters

Study Summary: Lay Summary for Participant Families

The BREATHE Study: Bronchiolitis Recovery and Use of HEPA Filters

Author(s): The BREATHE Study Team

Why was this study conducted?

Bronchiolitis is an infection that affects the airways of a child. Babies with bronchiolitis may need hospital treatment. These babies may still have breathing problems, such as coughing and wheezing, after they go home.

Many things can affect a person’s ability to breathe. One of those things is the level of very small particles in the air. These particles are called PM2.5, which are particulate matter that is less than 2.5 micrometers across. That size is smaller than the size of most pollen and mold. The level of these very small particles in the air in someone’s home can be lowered by special air filters called high efficiency particulate air (HEPA) filters.

The BREATHE study was done to find out if HEPA filters used in a baby’s house can help them breathe better than if no filter is used in their house. Specifically, the study looked at how many days infants, who previously had bronchiolitis, had specific breathing problems such as coughing, wheezing, or other breathing problems.

What was done?

Babies chosen for this study were less than 12 months old and had been hospitalized for bronchiolitis for the first time. Babies were selected from 17 hospitals, each in a different state. A total of 228 families were given either 2 HEPA units or 2 control units (identical units but with filters removed). One unit was to be used in the baby’s sleep space and the other unit in a common room of the home. Families did not know which types of units they were given. Air quality monitors measured the level of very small particles (PM2.5) in their homes. Families reported the number of days that their babies had breathing troubles. These reports were done weekly for 6 months. At the end of the study, families learned whether they had been using HEPA units or control units. All families were then given new HEPA filters. They also received individual reports about the PM2.5 levels in their home.

What was found?

The number of days babies had breathing problems were counted. The number of problem days for the babies living in homes with HEPA filters were compared to the number of problem days for the babies living in homes that had control units. Generally, babies in homes with working HEPA units had fewer breathing problems than babies in homes with the control units. Babies in homes with HEPA units had an average of 5 fewer days with breathing problems than did babies in homes with the control units. However, because the difference between the 2 groups is quite small, it is not clear if the breathing improvement was related to HEPA filter use or due to chance. This does not mean that the HEPA filters were not useful. It only means that it could not be proven with this study.

Compared to those with control units, babies who had HEPA filter units in their home had a 9% lower chance of unscheduled healthcare visits, such as hospitalizations, emergency room visits, and doctor’s office visits for breathing problems, but the difference between the 2 groups is small and may be due to chance. Babies who had HEPA filter units running most of the time during the study had a 25% lower chance of unscheduled doctor’s office visits for breathing problems.

On average, homes with working HEPA units had average common room PM2.5 equal to 11 micrograms per cubic meter (μg/m3). On average, levels were higher in the common room of homes with control units (15 μg/m3). The difference was even bigger in the infant’s sleep space. On average, homes with HEPA units had sleep space PM2.5 equal to 11 μg/m3. On average, homes with control units had sleep space PM2.5 equal to 21 μg/m3.

What do the results mean?

Filtering air with a HEPA unit may help infants who have been in the hospital for bronchiolitis. Infants in houses with HEPA units may have fewer days of breathing trouble than infants in houses without HEPA units. However, we would need to do a larger study to know for sure.

Who sponsored the study?

This research was supported by the Environmental influences on Child Health Outcomes (ECHO) program, the Office of the Director, National Institutes of Health.

Appreciation

The authors appreciate the children and families whose participation made the research possible.

The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

Lay Summary for the BREATHE Study (for participant distribution)
cIRB # 274137 V-01 (27-October-2025)

Living in Low-income-low-food-access Neighborhoods Linked to Higher Risk of Childhood Asthma

Posted on July 31, 2025July 31, 2025 by Jodi Snare

Living in a low-income neighborhood with low food access was associated with higher risks of developing asthma, according to a recent ECHO Cohort study led by Veronica A. Wang, PhD, Antonella Zanobetti, PhD, and Diane Gold, MD of Harvard T. H. Chan School of Public Health and Rima Habre, ScD of the University of Southern California.

Asthma is characterized by chronic inflammation in the lungs, and prior research shows that a nutritious diet can reduce airway inflammation. However, access to affordable and healthy foods is often difficult for many communities that have limited access to supermarkets or grocery stores. In this study, the researchers wanted to learn whether living in a low-income-low-food access neighborhood was associated with childhood asthma and whether this association was modified by sociodemographic factors.

The study included 16,012 children from 35 ECHO Cohort study sites across the U.S., and the investigators used low-income-low-food-access (LILA) neighborhood metrics from the U.S. Department of Agriculture’s Food Access Research Atlas to evaluate each child’s neighborhood food access.

Key Takeaways include:

Living in a low-income neighborhood with low food access was associated with higher risks of developing asthma for both cumulative early (age 0-5 years) and cumulative middle (age 0-11 years) childhood, which stronger associations observed for cumulative early childhood.
The increased risk of asthma was more noticeable among girls, Hispanic children, and children whose mothers had less than a high school education.
The findings suggest that food access in the immediate vicinity of residence and that vehicle access may be important and may contribute to disparities in childhood asthma development.

This collaborative research, titled “Residing in a low-income-low-food-access neighbourhood and asthma in early and middle childhood in the Environmental influences on Child Health Outcomes (ECHO) program: a multisite cohort study,” is published in BMJ Open.

Upper and Lower Airway

Breathing

ECHO researchers use data from more than 64,000 diverse children and their families across the U.S. to examine associations between environmental influences—such as neighborhood conditions, air pollution, or chemical exposures-a child's health history, family health history and circumstances, and airway health outcomes. In addition, the ECHO IDeA States Pediatric Clinical Trials Network (ISPCTN) conducts clinical trials focused on airway health.

ECHO Discovery
Webinar Recording

Christine Loftus, MS, MPH, Ph.D: Where there’s smoke… there’s action? What ECHO can do to protect children from wildfire smoke

Upper and Lower
Airway Resources

CDC: Learn How to Control Asthma
Provides information, facts, and articles from the CDC on asthma in children and adults.

MedlinePlus: Asthma in Children
Gives an overview of asthma in children, including information on preventing, identifying, treating, and living with childhood asthma.

U.S. Food and Drug Administration: Allergy Relief for Your Child
Describes allergies in children and treatments that may help.

QUESTIONS

For more information, please email the NIH at NIHKidsandEnvironment@od.nih.gov.
For media inquiries or to request an interview, contact Rebekah Yeager at rebekah.yeager@nih.gov.

How ECHO Advances Research on Upper and Lower Airway Health

In the U.S., asthma affects an estimated 5 million children—with higher rates for children living in poverty (11%), boys ages 5-14 (11%), and Black children (14%). Each year, children with poorly managed asthma experience more than 10 million missed school days, 74,000 hospital stays, and 767,000 trips to the emergency room.

Many factors can affect a child's airway health and disease and whether a child might develop breathing problems or respiratory diseases such as asthma. Research by the ECHO Program explores the social, physical, and behavioral factors that affect children's airway health. The focus is on understanding the early stages of airway health and disease, which may start during fetal development. It can also help to explain how a child's airway function might affect other areas of their health and well-being during childhood and adolescence. This research can help inform programs, policies, and practices that address health differences from the beginning, promoting a lifetime of good health that continues for generations.

What We're Learning

Since its launch, the ECHO Program has published more than 2,000 research articles on a wide range of child health topics. Within this body of work, many studies have examined upper and lower airway health.

Here are some research highlights:

The BREATHE Study: Bronchiolitis Recovery and Use of HEPA Filters
October 2025
In an ISPCTN study, infants living in homes with HEPA air filters had slightly fewer breathing problems and lower indoor air pollution than those in homes with control units.

ECHO Study Observes Health Disparities in Air Pollution-associated Risk of Childhood Asthma
August 2025
Children with higher early-life exposure to fine particulate matter, nitrogen dioxide, or ground-level ozone were more likely to develop asthma by age 10.

Children Living in Low-income Neighborhoods with Low Food Access at Higher Risk of Developing Asthma, ECHO Study Finds
June 2025
Children growing up in low-income neighborhoods with limited food access faced a higher asthma risk.

Children Born in Lower-Opportunity Neighborhoods Had Higher Rates of Asthma with Recurrent Exacerbations
March 2025
Children born in neighborhoods with low community opportunity had a much higher incidence rate of asthma with recurrent exacerbations (ARE) compared to those from other neighborhoods.

No Significant Associations Observed Between Prenatal Antibiotic Use and Wheezing Symptoms in Infants
February 2025
Prenatal antibiotic use was generally not linked to infant wheezing or hospital visits in the first 18 months, though it was associated with increased medication use for wheeze or cough.

ECHO Researchers Find Different Rhinoviruses Can Provide Limited Protection Against Each Other

Posted on October 20, 2023April 1, 2025 by Jodi Snare

Collaborative ECHO research led by Yury Bochkov, PhD and James Gern, PhD of the University of Wisconsin at Madison investigates similarities and differences in the immune responses to two types of rhinovirus—RV-A and RV-C. This research, titled “Rhinoviruses A and C elicit long-lasting antibody responses with limited cross-neutralization,” is published in the Journal of Medical Virology.

Of the three species of rhinoviruses (A, B, and C) that can cause upper respiratory illnesses, RV-A and RV-C are more likely to cause wheezing illnesses in preschoolers and in children and adults who have asthma. No specific vaccines for these viruses exist yet, in part because the large range of rhinovirus strains makes vaccine development difficult. The goal of this study was to test whether RV-C infections are more likely than RV-A infections to induce long-lasting antibodies that can protect against other RV-C strains.

Over 4,000 children ages 0 to 19 were enrolled in 14 independent studies across Australia, Finland, and the United States. The studies included healthy participants as well as those with asthma and RV illnesses of varying severity. Researchers found that while protective antibody responses to RV-C last for several years, they have only modest cross-species protection that is limited to genetically similar viruses.

“These findings suggest that vaccines against RV-C might need to include many of the most common RV-C types to offer broad protection,” Dr. Bochkov said.

Researchers would also like to determine why RV-C infections occur so frequently, and why they are more likely to cause wheezing illnesses. The ultimate goal of these studies is to help researchers design a practical RV-C vaccine that could protect high-risk children.

Read the research summary.

How Much Vitamin D do Children with Asthma and Increased Body Weight Need to Correct Low Vitamin D Levels?

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How much vitamin D do children with asthma and increased body weight need to correct low vitamin D levels?

Study title: Pharmacokinetics of Oral Vitamin D in Children with Obesity and Asthma

Author(s): Jason E. Lang, Rodrigo Gonzalez Ramirez, Stephen Balevic, Brian O’Sullivan, Scott Bickel, Christoph P. Hornik, J. Marc Majure, Saranya Venkatachalam, Jessica Snowden, Laura James

Why was this study conducted?

Among children with asthma, children who also have increased body weight for their height (body mass index (BMI) of ≥85 percentile) tend to have more severe asthma symptoms than their healthy weight peers. Children with asthma and increased body weight also tend to have lower vitamin D levels than other children. Helping children with asthma and increased body weight reach higher vitamin D levels may help their asthma symptoms by lowering inflammation in the lungs. However, there is not enough information on how much vitamin D children with asthma and increased body weight should take to safely raise their vitamin D levels.

What was done?

ECHO ISPCTN research teams in 15 states enrolled children ages 6‑18 years with asthma and increased body weight in a clinical trial. The children took vitamin D capsules for 16 weeks and gave blood samples every month so researchers could check their vitamin D levels. The goal of the study was to find a vitamin D dose that helped children raise their vitamin D levels in their blood to 40 ng/mL, a level that might lower inflammation.

There were two parts of the study. In the first part, children were split into four groups that each took one of four different doses of vitamin D to find a dose that raised children’s vitamin D levels over 16 weeks without causing side effects. All four dosing options were higher than what is usually recommended to raise vitamin D levels. Then, researchers compared the vitamin D dose from part 1 that raised vitamin D levels quickly and safely to the usually recommended daily vitamin D dose to confirm that the higher dose could safely help children reach vitamin D levels that may decrease inflammation. This study was approved by the Institutional Review Board and all participants consented to participate in the study.

What was found?

The first part of the study found that taking a 50,000 international units (IU) vitamin D dose on the first day of treatment and then an 8,000 IU vitamin D dose every day for 16 weeks was most effective at raising vitamin D levels safely. In the second part of the study, researchers confirmed that using this approach raised vitamin D levels in most children to the recommended level while avoiding undesired higher levels. In contrast, no children who followed the current standard-of-care dosing of 600 IU each day achieved the target vitamin D level sufficient to potentially reduce inflammation.

What do the results mean?

Most children with asthma and increased body weight who take vitamin D the vitamin D dose used in this study (50,000 IU vitamin D on day one, then 8,000 IU each day) can safely raise their vitamin D level in a short period of time. The newly determined dose is much greater than the typically recommended dose. This study shows how important it is that children and adolescents with increased body weight get enough vitamin D in their diet or in vitamin supplements every day since the higher the body weight, the faster vitamin D was processed and removed from the body. The results of this study may help children with asthma or other illnesses if having enough Vitamin D lowers inflammation.

Who sponsored the study?

This research was supported by the Environmental influences on Child Health Outcomes (ECHO) program, Office of The Director, National Institutes of Health.

Appreciation

All of the families in ECHO ISPCTN trials help study teams across the country learn more every day about how to bring rural and underserved families into research studies. This is critical to ensure that families that are not near large academic centers still get the benefits of research and that the “answers” research studies find are meaningful for children and families across all parts of the country, not just those who live in large cities.

You may learn more about this publication here: https://link.springer.com/article/10.1007/s40262-023-01285-9

The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

Published: August 30, 2023

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How much vitamin D do children with asthma and increased body weight need to correct low vitamin D levels?

Read Related Research Summaries

What Are factors That Affect the Incidence Rate of Asthma With Recurrent Exacerbations in Children?

Authors: Rachel L. Miller; Christine C. Johnson, et al.

A Nationwide Study on How Childhood Asthma Relates to Obesity Development

Authors: Nikos Stratakis and Erika Garcia

General health and life satisfaction in children with chronic illness

Author(s): Courtney K. Blackwell, et al

ECHO Study Suggests Neighborhood Conditions Throughout Childhood May Shape Risk of Developing Asthma

Authors: Izzuddin Aris, et al.

Study Shows Association Between Better Neighborhood Conditions and Lower Childhood Asthma Rates

Posted on August 28, 2023August 27, 2025 by Jodi Snare

FOR IMMEDIATE RELEASE

Living in a neighborhood with better access to resources such as high-quality housing, healthy food, parks and playgrounds, and clean air during the early stages of childhood was associated with lower asthma incidence in a new study from NIH’s Environmental influences on Child Health Outcomes (ECHO) Program.

Children born in high-opportunity neighborhoods had an asthma incidence rate of 23.3 cases per 1,000 children, while those born in very low and low-opportunity neighborhoods had rates of 35.3 per 1,000 and 27 per 1,000, respectively.

“Understanding neighborhood conditions could help researchers identify vulnerable children who are at high risk for developing asthma,” said study author Izzuddin Aris, PhD, of Harvard Medical School. “This information can also inform efforts by policymakers, researchers, and community groups to improve children's health and foster equity across neighborhoods.”

Researchers in this study measured neighborhood conditions using the Child Opportunity Index and the Social Vulnerability Index, which link residential addresses at birth, infancy (age 0.5‒1.5 years), and early childhood (age 2.0‒4.8 years) to census-tract data about the opportunities and resources available in the surrounding neighborhood. Only the Child Opportunity Index, which measures neighborhood resources and conditions deemed essential for healthy child development, showed significant associations with childhood asthma incidence. The Social Vulnerability Index measures factors that make a community more vulnerable in the aftermath of natural or human-caused disasters.

This study used data from 10,516 children at 46 research sites participating in ECHO, each having at least one residential address from birth and a parent or caregiver report of a physician’s diagnosis of asthma. These differences in the incidence of asthma persisted even after controlling for sociodemographic characteristics, parental asthma history, and the number of births a mother had.

“These findings emphasize the importance of investigating whether investing in early-life health and environmental or social and economic resources can promote health equity in pediatric asthma,” said Dr. Aris.

Dr. Aris led this collaborative research published in JAMA Pediatrics. An embargoed copy of the study is available upon request.

###

About ECHO:

Launched in 2016, the Environmental influences on Child Health Outcomes (ECHO) Program is a research program in the Office of the Director at the NIH with the mission to enhance the health of children for generations to come. ECHO investigators study the effects of a broad range of early environmental influences on child health and development. For more information, visit echochildren.org.

About the NIH: NIH, the nation’s medical research agency, includes 27 Institutes and Centers and is a component of the U.S. Department of Health and Human Services. NIH is the primary federal agency conducting and supporting basic, clinical, and translational medical research, and is investigating the causes, treatments, and cures for both common and rare diseases. For more information, visit www.nih.gov.

Media Contacts

For information or to request an interview, contact Rebekah Yeager, rebekah.yeager@nih.gov.

If you are not a member of the media, but have a general inquiry, please contact NIHKidsandEnvironment@od.nih.gov.

Connect With Us

Check out the recent issues of our bi-monthly newsletter, the ECHO Connector, for program news and the latest research findings.

To receive the ECHO Connector through email, subscribe here.

Follow @ECHOChildHealth for the latest ECHO Program updates on Twitter.

Can Neighborhood Conditions Throughout Childhood Shape the Risk of Developing Asthma?

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ECHO Study Suggests Neighborhood Conditions Throughout Childhood May Shape Risk of Developing Asthma

Authors: Izzuddin Aris, et al.

Who sponsored this study?

The Environmental influences on Child Health Outcomes (ECHO) Program, Office of the Director, National Institutes of Health supported this research.

Why was this study needed?

Neighborhood conditions, such as access to housing, healthy food, transportation, and education centers, can contribute to the development of childhood asthma. Researchers often measure these conditions using the Child Opportunity Index and the Social Vulnerability Index, which link residential addresses at birth, infancy (age 0.5‒1.5 years), and early childhood (age 2.0‒4.8 years) to census-tract data about the opportunities and resources available in the surrounding neighborhood. Previous studies looking into this topic lacked geographic diversity or considered only specific socioeconomic aspects of neighborhood disadvantage, which may not fully capture the role of early-life experiences on health outcomes. This study examines the association of conditions and resources available in neighborhoods during different developmental stages with childhood asthma incidence.

What were the study results?

Living in a neighborhood with higher opportunity at birth, infancy, or early childhood was associated with lower asthma incidence when compared to living in a neighborhood with lower opportunity. Differences in sociodemographic characteristics, parental asthma history, or the number of births a mother had did not explain this effect.

Footnote: Results reported here are for a single study. Other or future studies may provide new information or different results. You should not make changes to your health without first consulting your healthcare professional.

What was the impact?

Neighborhood conditions could help researchers identify vulnerable children who are at high risk for developing asthma. Policymakers, researchers, and community groups can use this information to guide decisions and interventions to improve the health of children and promote equitable opportunities across neighborhoods.

Who was involved?

This study used data from 10,516 children at 46 research sites participating in ECHO. The participants have at least one residential address from birth and a parent or caregiver report of a physician’s diagnosis of asthma.

What happened during the study?

Researchers linked participants’ residential addresses to the Child Opportunity Index and Social Vulnerability Index. They estimated asthma incidence rates associated with Child Opportunity Index or Social Vulnerability Index data for a child’s neighborhood at each life stage, adjusting for sociodemographic characteristics, maternal and paternal history of asthma, and the number of births a mother had.

What happens next?

Future studies can explore the impact of investing in early life health and environmental, social, and economic resources on improving health outcomes for children in disadvantaged neighborhoods. Follow-up studies can also focus on how these neighborhood-level factors are affecting asthma rates and how moving may alter asthma development.

Where can I learn more?

Access the full journal article, titled “Associations of Neighborhood Opportunity and Vulnerability with Incident Asthma Among U.S. Children in the ECHO cohorts,” in JAMA Pediatrics.

The content is the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

Published August 28, 2023

Access the associated article.

Download this summary

ECHO Study Suggests Neighborhood Conditions Throughout Childhood May Shape Risk of Developing Asthma

ECHO Researchers Investigate Link Between Neighborhood Conditions During Childhood and Asthma Incidence

Posted on August 28, 2023August 28, 2023 by Jodi Snare

Collaborative ECHO research led by Izzuddin Aris, PhD, of Harvard Medical School examined the association of conditions and resources available in neighborhoods during different development stages with childhood asthma incidence.

Neighborhood conditions, such as access to housing, healthy food, transportation, and education centers, can influence the development of childhood asthma. Researchers often measure these conditions using the Child Opportunity Index and the Social Vulnerability Index, which link residential addresses at birth, infancy (age 0.5‒1.5 years), and early childhood (age 2.0‒4.8 years) to census-tract data about the opportunities and resources available in the surrounding neighborhood.

ECHO researchers used data from 10,516 children at 46 research sites participating in the ECHO Program. The participants had at least one residential address from birth and a parent or caregiver report of a physician’s diagnosis of asthma.

Children born in high-opportunity neighborhoods had an asthma incidence rate of 23.3 cases per 1,000 children, while those born in very low and low-opportunity neighborhoods had rates of 35.3 per 1,000 and 27 per 1,000, respectively.

“Neighborhood conditions could help researchers identify vulnerable children who are at high risk for developing asthma,” said Dr. Aris. “This information can also guide policymakers, researchers, and community groups to improve children’s health and foster equity across neighborhoods.”

Future studies can explore the impact of investing in early life health and environmental, social, and economic resources on improving health outcomes for children in disadvantaged neighborhoods. Follow-up studies can also focus on how these neighborhood-level factors are affecting asthma rates and how moving may alter asthma development.

This research, titled “Associations of Neighborhood Opportunity and Vulnerability with Incident Asthma Among U.S. Children in the ECHO cohorts,” is published in JAMA Pediatrics.

Read the research summary.

Specific Social, Environmental Factors May Influence Incidence Rates of Childhood Asthma with Recurrent Exacerbations

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Specific Social, Environmental Factors May Influence Incidence Rates of Childhood Asthma with Recurrent Exacerbations

Authors: Rachel L. Miller; Christine C. Johnson, et al.

Who sponsored this study?

This research was supported by the Environmental influences on Child Health Outcomes (ECHO) Program, Office of The Director, National Institutes of Health.

Why was this study needed?

While the prevalence of asthma has been reported widely in the United States and elsewhere, studies on childhood asthma incidence rates within specific populations and across various types of asthma and age ranges have been relatively sparse. Describing the incidence rates of ARE across various pediatric populations is a critical first step for identifying potential risk factors and causes.

What were the study results?

In this study, investigators wanted to gather more information about factors that influence the rates of childhood asthma with recurrent exacerbations (ARE)—a subtype of asthma where children experience frequent, severe episodes of asthma.

ARE incidence rates were highest among children ages 2-4 years old, and among non-Hispanic Black and Hispanic Black children. ARE rates were also higher among children living in the Northeast and Midwest compared to those living in the West. Children with a parental history of asthma had ARE rates 2.9 times greater compared to those with no parental history.

Footnote: Results reported here are for a single study. Other or future studies may provide new information or different results. You should not make changes to your health without first consulting your healthcare professional.

What was the impact?

Higher incidence rates of ARE among young children, non-Hispanic Black and Hispanic Black children, and children living in the Northeast and Midwest suggest that differential environmental exposures may play a significant role in the onset of recurring asthma issues in children. ARE rates are consistently higher among children with a parental history of asthma, especially for young children, which may be due to a combination of genetic, environmental, and family lifestyle factors.

Who was involved?

The research team leveraged data from 17,246 children born between 1990 and 2017 who were enrolled in 60 ECHO research sites in the U.S. and Puerto Rico. Child participants or their caregivers reported whether and when the child had an asthma diagnosis and any oral corticosteroids prescribed from a health care provider. Incidence rates of ARE were based on reports of systemic (not inhaled) corticosteroid use.

Of the 4,114 children diagnosed with asthma during this study, there were 2,061 children with at least one asthma episode when they used oral steroid medication; 734 of these children had 2 or more asthma episodes with steroid medication use and met the conditions for ARE.

What happened during the study?

The researchers calculated the incidence rates of ARE for the study population as a whole, along with the rates for subsets of the population defined by the year of ARE diagnosis, the decade they were born, their age and sex, their race and ethnicity, their residence at birth, and their parents’ history of asthma. The researchers followed the children from birth until they developed ARE, reached the age of 20 years or the study period ended. The study identified children who developed ARE based on at least two reports of systemic steroid medication use at any time during the entire follow-up period. Children who received asthma diagnoses before age 5 years were required to have confirmation after 5 years, either by a parent or caregiver, adolescent self-report of asthma symptoms, hospitalization, emergency department or urgent care visit for asthma, provider visits due to asthma, or asthma medication use.

What happens next?

ECHO researchers are planning new studies that examine key early environmental exposures that could contribute to ARE, including viral respiratory tract infections, indoor allergens, environmental tobacco smoke, air pollution, stress, socioeconomic status, and where children live.

Where can I learn more?

Access the full journal article, titled “Incidence Rates of Childhood Asthma with Recurrent Exacerbations in the U.S. Environmental influences on Child Health Outcomes (ECHO) Program,” in The Journal of Allergy and Clinical Immunology.

The content is the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

Published March 25, 2023

Access the associated article.

Download this summary

Specific Social, Environmental Factors May Influence Incidence Rates of Childhood Asthma with Recurrent Exacerbations

ECHO Researchers Examine Incidence Rates for Childhood Asthma With Recurrent Exacerbations and Suggest Possible Social and Environmental Risk Factors

Posted on May 10, 2023December 4, 2023 by Jodi Snare

Collaborative ECHO research led by Rachel L. Miller, MD of Icahn School of Medicine at Mount Sinai and Christine C. Johnson, PhD, MPH of Henry Ford Health System investigates the factors that influence the rates of childhood asthma with recurrent exacerbations (ARE)—a subtype of asthma where children experience frequent, severe episodes of asthma. The researchers leveraged data from over 17,000 children born between 1990 and 2017 and found that children ages 2-4 years old, non-Hispanic Black and Hispanic Black children, and children who lived in the Northeast and Midwest had the highest incidence rates of ARE. Additionally, children with a parental history of asthma had ARE rates almost 3 times greater compared to those with no parental history. This research, titled “Incidence Rates of Childhood Asthma with Recurrent Exacerbations in the U.S. Environmental influences on Child Health Outcomes (ECHO) Program,” is published in The Journal of Allergy and Child Immunology.

While the prevalence of asthma has been reported widely in the United States and elsewhere, studies on childhood asthma incidence rates within specific populations and across various types of asthma and age ranges have been limited. “Describing the incidence rates of ARE across a large, diverse population of children is a critical first step for identifying potential risk factors and causes,” explained Dr. Johnson.

To conduct this research, the research team leveraged data from children enrolled in 60 ECHO cohorts across the U.S. and Puerto Rico. Child participants or their caregivers reported whether and when the child had an asthma diagnosis and any corticosteroids prescribed over time from their health care providers. Recurrent exacerbations of asthma were based on reports of systemic (not inhaled) corticosteroid use. The researchers calculated incidence rates of ARE for the study population overall, along with rates for subsets of the population defined by the years the ARE were diagnosed, the decade children were born, their age and sex, their race and ethnicity, their residence at birth, and their parents’ history of asthma.

“While children with ARE are all different, these findings suggest that we should examine in the future key elements of the early environment, including viral respiratory tract infections, indoor allergens, environmental tobacco smoke, air pollution, stress, and socioeconomic status, which could contribute to ARE,” said Dr. Miller. “Understanding these causes will help researchers determine how to best prevent ARE and associated asthma outcomes.”

Read the research summary.

Study Summary: Lay Summary for Participant Families