{"doi":"10.1101/2021.03.01.21252712","title":"Long-term Exposures to Air Pollutants Affect FeNO in Children: A Longitudinal Study","abstract":"ABSTRACT Fractional exhaled nitric oxide (FeNO) is a marker of airway inflammation shown to be responsive to short-term air pollution exposures; however, effects of long-term exposures are uncertain. Using longitudinal assessments of FeNO and air pollutant exposures, we aimed to determine whether FeNO is a marker for chronic effects of air pollution exposures after accounting for short-term exposures effects. FeNO was assessed up to six times 2004-2012 in 3607 schoolchildren from 12 communities in the Southern California Children’s Health Study. Within-community long-term ambient air pollution exposures (PM 2.5 , PM 10 , NO 2 , O 3 ) were represented by differences between community-specific annual averages and the eight-year average spanning the study period. Linear mixed-effect models estimated within-participant associations of annual average air pollution with current FeNO, controlling for previous FeNO, prior seven-day average pollution, potential confounders, and community-level random intercepts. We considered effect modification by sex, ethnicity, asthma, and allergy at baseline. We found FeNO was positively associated with annual average air pollution, after accounting for short-term exposures. One standard deviation higher annual PM 2.5 and NO 2 exposures (PM 2.5: 2.0 μg/m 3 ; NO 2 :2.7 ppb) were associated, respectively, with 4.6% (95%CI:2.3%-6.8%) and 6.5% (95%CI:4.1%-8.9%) higher FeNO. These associations were larger among females. We found little evidence supporting association with PM 10 or O 3 . Annual average PM 2.5 and NO 2 levels were associated with FeNO in schoolchildren, adding new evidence that long-term exposure affects FeNO beyond the well-documented short-term effects. Longitudinal FeNO measurements may be useful as an early marker of chronic respiratory effects of long-term PM 2.5 and NO 2 exposures in children. Key messages We show strong evidence that long-term exposures to air pollutants affect FeNO, independent of the well-documented associations with short-term exposures to air pollution Longitudinal FeNO measurements may be useful as an early marker of chronic respiratory effects of long-term air pollution exposures in children. Capsule summary Annual average PM 2.5 and NO 2 were associated with FeNO in schoolchildren, adding new evidence that long-term exposure affects FeNO beyond the well-documented short-term effects.","journal":"medRxiv","year":2021,"id":217228,"datarank":0.20794415416798362,"base_score":1.3862943611198906,"endowment":1.3862943611198906,"self_citation_contribution":0.20794415416798362,"citation_network_contribution":0.0,"self_endowment_contribution":0.20794415416798362,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":3,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9516,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2021-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":307227,"name":"Sandrah P. Eckel","orcid":"0000-0001-6050-7880","position":1,"is_corresponding":false},{"id":261785,"name":"Kiros Berhane","orcid":"0000-0003-2303-8493","position":2,"is_corresponding":false},{"id":471366,"name":"Erika Garcia","orcid":"0000-0003-1540-9805","position":3,"is_corresponding":false},{"id":814666,"name":"Patrick Muchmore","orcid":null,"position":4,"is_corresponding":false},{"id":814667,"name":"Noa Molshatzki","orcid":null,"position":5,"is_corresponding":false},{"id":814038,"name":"Edward B. Rappaport","orcid":"0000-0002-7044-3515","position":6,"is_corresponding":false},{"id":595377,"name":"William S. Linn","orcid":null,"position":7,"is_corresponding":false},{"id":285019,"name":"Rima Habre","orcid":"0000-0003-2103-1706","position":8,"is_corresponding":false},{"id":75356,"name":"Frank D. Gilliland","orcid":"0000-0002-9033-7269","position":9,"is_corresponding":false},{"id":424143,"name":"Yue Zhang","orcid":"0000-0002-4124-4816","position":0,"is_corresponding":true}],"reference_count":35,"raw_metadata":{"citation_network_status":"fetched"},"created_at":"2026-07-18T23:53:20.374789Z","pmid":null,"pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}