Home Air Pollution in Children With Cystic Fibrosis Study (HEROIC-CF)

Cystic Fibrosis (CF) is a devastating chronic pulmonary disease that continues to cause significant morbidity and mortality despite great advances in therapies. Hispanic children with CF have worse outcomes, including higher mortality and more severe pulmonary disease, than non-Hispanic white children with CF. It is not known why Hispanic children with CF have more severe disease as it is not explained by CFTR genetic severity, diagnosis age, or socioeconomic status. The health disparities have worsened, not improved, for Hispanic children with CF since the development of new disease-altering therapeutics, CFTR modulators. It is critical to determine what is contributing to lung disease severity in Hispanic children with CF. Non-genetic factors, including environmental exposures, are estimated to account for 50% of lung disease severity variability in CF. Air pollution exposure during early childhood is associated with lower pulmonary function in healthy children and severe lung disease in children with asthma. However, air pollution exposure is vastly understudied in other chronic pulmonary diseases of childhood, such as CF. Investigating air pollution exposure in CF may provide vital information about the drivers of health disparities in Hispanic children with CF and about the environmental exposures influencing lung disease severity across all children with CF. To investigate air pollution exposure in children with CF, the investigators have assembled a multidisciplinary team of international experts in air pollution exposure, CF lung disease, health disparities, and pulmonary microbiome. The investigators will use two phenomenally rich databases, the CF Foundation Patient Registry and the University of Washington Spatiotemporal Air Pollution Exposure Model, to investigate the first aim: 1A) To determine whether neighborhood-level ambient air pollution exposure during childhood differs between 1500 Hispanic and 8500 non-Hispanic white cwCF in the CF Foundation Patient Registry, and 1B) To determine if neighborhood-level ambient air pollution exposure is associated with lung disease severity in Hispanic and non-Hispanic white cwCF. Across six geographically diverse clinical research CF centers, the investigators will enroll 100 Hispanic and 100 non-Hispanic children with CF to investigate the following aims: 2) To assess differences in residential indoor and ambient air pollution exposures by ethnicity in 200 cwCF, as well as the association between such exposure and pulmonary function by ethnicity, 3) To investigate the association of indoor and ambient air pollution exposure on airway inflammation and microbiome diversity and composition in Hispanic and non-Hispanic white cwCF using metatranscriptomic RNA sequencing. The HEROIC-CF Study is poised to advance the knowledge of the effect of air pollution exposure on not only CF lung disease severity, but may be a model to understand environmental exposures on disease severity in other chronic pulmonary diseases of childhood.

Study Overview

• Status: Not yet recruiting
• Conditions: Cystic Fibrosis (CF)

• Study Type: Observational
• Enrollment (Estimated): 200

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Children with confirmed cystic fibrosis

Description

Inclusion Criteria:

• Age 6 to 18 years old
• Hispanic of any race or non-Hispanic white
• Diagnosed with cystic fibrosis

Exclusion Criteria:

• Cannot perform spirometry
• Planning to move in next 12 months
• Spends <4 nights a week in one residence
• Active smoking in the home

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Indoor Air Pollution	Measurement of PM2.5 indoors via PurpleAir monitors	12 Months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Pulmonary Function	Pulmonary Function Test (PFT) using spirometry: FVC, FEV1, FEV1/FVC, and FEF25%-75%	12 months
Airway inflammation	Airway inflammation will be measured using sequencing of oropharyngeal swabs	12 months
Airway microbiome	Airway microbiome will be measured using sequencing of oropharyngeal swabs	12 months

Collaborators and Investigators

• Sponsor: Seattle Children's Hospital
• Collaborators: National Heart, Lung, and Blood Institute (NHLBI)

Study record dates

Study Major Dates

• Study Start (Estimated): September 1, 2026
• Primary Completion (Estimated): April 30, 2031
• Study Completion (Estimated): April 30, 2031

Study Registration Dates

• First Submitted: June 12, 2026
• First Submitted That Met QC Criteria: June 17, 2026
• First Posted (Actual): June 24, 2026

Study Record Updates

• Last Update Posted (Actual): June 24, 2026
• Last Update Submitted That Met QC Criteria: June 17, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Keywords: cystic fibrosis; air pollution
• Additional Relevant MeSH Terms: Genetic Diseases, Inborn; Respiratory Tract Diseases; Digestive System Diseases; Lung Diseases; Infant, Newborn, Diseases; Pancreatic Diseases; Congenital, Hereditary, and Neonatal Diseases and Abnormalities; Cystic Fibrosis
• Other Study ID Numbers: STUDY00005521

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No