title: Obesity disproportionately impacts lung volumes, airflow and exhaled nitric oxide in children.
abstract: BACKGROUND
  The current literature focusing on the effect of obesity and overweight on lung function and fraction of exhaled nitric oxide (FeNO) in children, particularly among healthy children of non-European descent, remains controversial. Furthermore, whether the relationship of obesity and overweight with lung function and FeNO in children is modified by atopy is unclear. The objective of this study was to examine the effect of excess weight on lung function parameters and FeNO among Asian children, with a particular focus on exploring the potential effect modification by atopy.
  
  
  METHODS
  We investigated the effect of excess weight on lung function and FeNO in a population sample of 1,717 children aged 5 to 18 years and explored the potential modifying effect of atopy.
  
  
  RESULTS
  There were positive associations of body mass index (BMI) z-score with forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), peak expiratory flow (PEF), and forced expiratory flow at 25-75% (FEF25-75) (all P<0.001), after controlling for confounders. The beta coefficient for FEV1 (0.084) was smaller than that for FVC (0.111). In contrast, a negative association was found between BMI z-score and FEV1/FVC ratio (P<0.001) and FeNO (P = 0.03). A consistent pattern of association for lung function variables was observed when stratifying by atopy. There was a negative association of BMI z-score with FeNO in atopic subjects (P = 0.006), but not in non-atopic subjects (P = 0.46).
  
  
  CONCLUSIONS
  Excess weight disproportionately impacts lung volumes and airflow in children from the general population, independent of atopic status. Excess weight inversely affects FeNO in atopic but not in non-atopic children.
authors.affiliation: Division of Allergy, Asthma, and Rheumatology, Department of Pediatrics, Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Taoyuan, Taiwan.|Chang Gung Immunology Consortium, Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Taoyuan, Taiwan.|Community Medicine Research Center, Chang Gung Memorial Hospital at Keelung, Keelung, Taiwan.
authors.forename: Tsung-Chieh
authors.initials: TC
authors.lastname: Yao
authors.affiliation: Division of Biostatistics and Bioinformatics, Institutes of Population Health Sciences, National Health Research Institutes, Miaoli, Taiwan.|Department of Pediatrics, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America.|Allergy and Clinical Immunology Research Center, National Cheng Kung University, Tainan, Taiwan.
authors.forename: Hui-Ju
authors.initials: HJ
authors.lastname: Tsai
authors.affiliation: Division of Allergy, Asthma, and Rheumatology, Department of Pediatrics, Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Taoyuan, Taiwan.|Clinical Informatics and Medical Statistics Research Center, Chang Gung University College of Medicine, Taoyuan, Taiwan.
authors.forename: Su-Wei
authors.initials: SW
authors.lastname: Chang
authors.affiliation: Division of Biostatistics and Bioinformatics, Institutes of Population Health Sciences, National Health Research Institutes, Miaoli, Taiwan.
authors.forename: Ren-Hua
authors.initials: RH
authors.lastname: Chung
authors.affiliation: Division of Allergy, Asthma, and Rheumatology, Department of Pediatrics, Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Taoyuan, Taiwan.|Community Medicine Research Center, Chang Gung Memorial Hospital at Keelung, Keelung, Taiwan.
authors.forename: Jing-Ya
authors.initials: JY
authors.lastname: Hsu
authors.affiliation: Community Medicine Research Center, Chang Gung Memorial Hospital at Keelung, Keelung, Taiwan.|Department of Pediatrics, Chang Gung Memorial Hospital at Keelung, Keelung, Taiwan.
authors.forename: Ming-Han
authors.initials: MH
authors.lastname: Tsai
authors.affiliation: Community Medicine Research Center, Chang Gung Memorial Hospital at Keelung, Keelung, Taiwan.|Department of Pediatrics, Chang Gung Memorial Hospital at Keelung, Keelung, Taiwan.
authors.forename: Sui-Ling
authors.initials: SL
authors.lastname: Liao
authors.affiliation: Community Medicine Research Center, Chang Gung Memorial Hospital at Keelung, Keelung, Taiwan.|Department of Pediatrics, Chang Gung Memorial Hospital at Keelung, Keelung, Taiwan.
authors.forename: Man-Chin
authors.initials: MC
authors.lastname: Hua
authors.affiliation: Community Medicine Research Center, Chang Gung Memorial Hospital at Keelung, Keelung, Taiwan.|Division of Pediatric Pulmonology, Department of Pediatrics, Chang Gung Memorial Hospital, Taoyuan, Taiwan.
authors.forename: Shen-Hao
authors.initials: SH
authors.lastname: Lai
authors.affiliation: Division of Allergy, Asthma, and Rheumatology, Department of Pediatrics, Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Taoyuan, Taiwan.|Community Medicine Research Center, Chang Gung Memorial Hospital at Keelung, Keelung, Taiwan.
authors.forename: Li-Chen
authors.initials: LC
authors.lastname: Chen
authors.affiliation: Division of Allergy, Asthma, and Rheumatology, Department of Pediatrics, Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Taoyuan, Taiwan.|Community Medicine Research Center, Chang Gung Memorial Hospital at Keelung, Keelung, Taiwan.
authors.forename: Kuo-Wei
authors.initials: KW
authors.lastname: Yeh
authors.affiliation: Division of Allergy, Asthma, and Rheumatology, Department of Pediatrics, Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Taoyuan, Taiwan.|Community Medicine Research Center, Chang Gung Memorial Hospital at Keelung, Keelung, Taiwan.
authors.forename: Yu-Lun
authors.initials: YL
authors.lastname: Tseng
authors.affiliation: Division of Allergy, Asthma, and Rheumatology, Department of Pediatrics, Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Taoyuan, Taiwan.|Community Medicine Research Center, Chang Gung Memorial Hospital at Keelung, Keelung, Taiwan.
authors.forename: Wan-Chen
authors.initials: WC
authors.lastname: Lin
authors.affiliation: Division of Allergy, Asthma, and Rheumatology, Department of Pediatrics, Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Taoyuan, Taiwan.|Community Medicine Research Center, Chang Gung Memorial Hospital at Keelung, Keelung, Taiwan.
authors.forename: Su-Ching
authors.initials: SC
authors.lastname: Chang
authors.affiliation: Division of Allergy, Asthma, and Rheumatology, Department of Pediatrics, Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Taoyuan, Taiwan.|Community Medicine Research Center, Chang Gung Memorial Hospital at Keelung, Keelung, Taiwan.
authors.forename: Jing-Long
authors.initials: JL
authors.lastname: Huang
mesh_terms: D000293:Adolescent; D015992:Body Mass Index; D002648:Child; D002675:Child, Preschool; D045853:Exhalation / Q000502:physiology; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000150:complications / Q000503:physiopathology; D008168:Lung / Q000503:physiopathology*; D008297:Male; D008450:Maximal Midexpiratory Flow Rate; D009569:Nitric Oxide / Q000502:physiology*; D009765:Obesity / Q000150:complications / Q000473:pathology / Q000503:physiopathology*; D010366:Peak Expiratory Flow Rate; D012123:Pulmonary Ventilation; D012129:Respiratory Function Tests; D014797:Vital Capacity
chemical_list: D009569:Nitric Oxide