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Pham YL, Beauchamp J. Breath Biomarkers in Diagnostic Applications. Molecules 2021; 26:molecules26185514. [PMID: 34576985 PMCID: PMC8468811 DOI: 10.3390/molecules26185514] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 09/07/2021] [Accepted: 09/08/2021] [Indexed: 02/06/2023] Open
Abstract
The detection of chemical compounds in exhaled human breath presents an opportunity to determine physiological state, diagnose disease or assess environmental exposure. Recent advancements in metabolomics research have led to improved capabilities to explore human metabolic profiles in breath. Despite some notable challenges in sampling and analysis, exhaled breath represents a desirable medium for metabolomics applications, foremost due to its non-invasive, convenient and practically limitless availability. Several breath-based tests that target either endogenous or exogenous gas-phase compounds are currently established and are in practical and/or clinical use. This review outlines the concept of breath analysis in the context of these unique tests and their applications. The respective breath biomarkers targeted in each test are discussed in relation to their physiological production in the human body and the development and implementation of the associated tests. The paper concludes with a brief insight into prospective tests and an outlook of the future direction of breath research.
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Affiliation(s)
- Y Lan Pham
- Department of Sensory Analytics and Technologies, Fraunhofer Institute for Process Engineering and Packaging IVV, Giggenhauser Straße 35, 85354 Freising, Germany;
- Department of Chemistry and Pharmacy, Chair of Aroma and Smell Research, Friedrich-Alexander-Universität Erlangen-Nürnberg, Henkestraße 9, 91054 Erlangen, Germany
| | - Jonathan Beauchamp
- Department of Sensory Analytics and Technologies, Fraunhofer Institute for Process Engineering and Packaging IVV, Giggenhauser Straße 35, 85354 Freising, Germany;
- Correspondence:
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Garcia E, Zhang Y, Rappaport EB, Berhane K, Muchmore P, Silkoff PE, Molshatzki N, Gilliland FD, Eckel SP. Patterns and determinants of exhaled nitric oxide trajectories in schoolchildren over a 7-year period. Eur Respir J 2020; 56:13993003.00011-2020. [PMID: 32299857 DOI: 10.1183/13993003.00011-2020] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Accepted: 03/24/2020] [Indexed: 11/05/2022]
Abstract
Fractional exhaled nitric oxide (F ENO50 ), a marker of allergic airway inflammation, is used in respiratory research and asthma clinical care; however, its trajectory with increasing age during childhood has not been well characterised. We examined F ENO50 longitudinally during a period of important somatic growth to describe trajectories across childhood and adolescence in healthy participants and evaluate clinical factors as potential determinants of trajectories.F ENO50 was collected at six visits over 8 years in a population-based cohort of 1791 schoolchildren without asthma (median age at entry 8.4 years). Smooth sex-specific F ENO50 trajectories were estimated using generalised additive mixed models, with participant-level random effects. We evaluated whether sex-specific trajectories were influenced by race/ethnicity, body mass index (BMI) percentile, allergic rhinitis or puberty.Different F ENO50 patterns were observed by sex in later childhood and several factors were associated with either F ENO50 level or change in F ENO50 as participants aged. F ENO50 -age trajectories were similar by sex until age ∼11.5 years, after which males had greater F ENO50 change than females. This divergence in F ENO50 -age trajectories coincides with puberty. Males with higher starting BMI percentile had attenuated F ENO50 -age slopes. Among males, F ENO50 levels were lower in non-Hispanic white subjects. Among both sexes, participants with rhinitis had higher F ENO50 F ENO50 levels within individuals tracked over time; however, there was considerable variation in F ENO50 patterns across participants.F ENO50 trajectories from longitudinal data provide evidence of sex differences coinciding with puberty, suggesting potential hormone link. Improved understanding of determinants of F ENO50 trajectories is needed to realise the potential for using individualised predicted F ENO50 trajectories.
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Affiliation(s)
- Erika Garcia
- Dept of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Yue Zhang
- Dept of Internal Medicine, University of Utah, Salt Lake City, UT, USA
| | - Edward B Rappaport
- Dept of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Kiros Berhane
- Dept of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Patrick Muchmore
- Dept of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | | | - Noa Molshatzki
- Dept of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Frank D Gilliland
- Dept of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Sandrah P Eckel
- Dept of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
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Heffler E, Carpagnano GE, Favero E, Guida G, Maniscalco M, Motta A, Paoletti G, Rolla G, Baraldi E, Pezzella V, Piacentini G, Nardini S. Fractional Exhaled Nitric Oxide (FENO) in the management of asthma: a position paper of the Italian Respiratory Society (SIP/IRS) and Italian Society of Allergy, Asthma and Clinical Immunology (SIAAIC). Multidiscip Respir Med 2020; 15:36. [PMID: 32269772 PMCID: PMC7137762 DOI: 10.4081/mrm.2020.36] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Accepted: 02/05/2020] [Indexed: 02/08/2023] Open
Abstract
Asthma prevalence in Italy is on the rise and is estimated to be over 6% of the general population. The diagnosis of asthma can be challenging and elusive, especially in children and the last two decades has brought evidences that asthma is not a single disease but consists of various phenotypes. Symptoms can be underestimated by the patient or underreported to the clinician and physical signs can be scanty. Usual objective measures, like spirometry, are necessary but sometimes not significant. Despite proper treatment, asthma can be a very severe condition (even leading to death), however new drugs have recently become available which can be very effective in its control. Since asthma is currently thought to be caused by inflammation, a direct measure of the latter can be of paramount importance. For this purpose, the measurement of Fractional Exhaled Nitric Oxide (FENO) has been used since the early years of the current century as a non-invasive, easy-to-assess tool useful for diagnosing and managing asthma. This SIP-IRS/SIAAIC Position Paper is a narrative review which summarizes the evidence behind the usefulness of FENO in the diagnosis, management and phenotypization of asthma.
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Affiliation(s)
- Enrico Heffler
- Personalized Medicine, Asthma and Allergy, Humanitas Clinical and Research Center IRCCS, Rozzano (MI).,Department of Biomedical Sciences, Humanitas University, Pieve Emanuele (MI)
| | - Giovanna Elisiana Carpagnano
- Department of Medical and Surgical Sciences, University of Foggia; Section of Respiratory Diseases, Hospital d'Avanzo, Foggia
| | - Elisabetta Favero
- Department of Medicine-DIMED, Immunological and Respiratory Rare Disease, Allergologic Clinic Ca' Foncello Hospital, Treviso
| | - Giuseppe Guida
- Allergy and Pneumology Unit, A.O. S. Croce e Carle, Cuneo
| | - Mauro Maniscalco
- Respiratory Rehabilitation Unit, ICS Maugeri, Institute of Telese Terme IRCCS
| | - Andrea Motta
- Institute of Biomolecular Chemistry, National Research Council, Pozzuoli (NA)
| | - Giovanni Paoletti
- Personalized Medicine, Asthma and Allergy, Humanitas Clinical and Research Center IRCCS, Rozzano (MI).,Department of Biomedical Sciences, Humanitas University, Pieve Emanuele (MI)
| | - Giovanni Rolla
- Allergy and Clinical Immunology, University of Turin and A.O. Mauriziano, Turin
| | - Eugenio Baraldi
- Department of Woman's and Child's Health, University Hospital of Padua
| | - Vincenza Pezzella
- Department of Woman, Child and of General and Specialized Surgery, University of Campania "Luigi Vanvitelli", Naples
| | - Giorgio Piacentini
- Paediatric Section, Department of Surgery, Dentistry, Paediatrics and Gynaecology, University of Verona
| | - Stefano Nardini
- Italian Respiratory Society-Società Italiana di Pneumologia, Milan, Italy
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Kalidoss R, Umapathy S. A comparison of online and offline measurement of exhaled breath for diabetes pre-screening by graphene-based sensor; from powder processing to clinical monitoring prototype. J Breath Res 2019; 13:036008. [PMID: 30794992 DOI: 10.1088/1752-7163/ab09ae] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Several breath analysis studies have suggested a correlation between blood glucose (BG) levels and breath acetone, indicating acetone as a primary biomarker in exhaled breath for diabetes diagnosis. Herein, we have (i) fabricated and validated graphene-based chemi-resistive sensors for selective and sensitive detection of acetone, (ii) performed offline breath analysis by a static gas sensing set-up to acquire olfactory signals, and (iii) developed an LED-based portable on/off binary e-nose system for pre-screening diabetes through online analysis. The fabricated sensors showed selective detection for acetone with high sensitivity (5.66 for 1 ppm acetone vapor) and fast response and recovery times (10 s and 12 s) at low concentrations. The sensor responses of end tidal fractional breath (collected in Tedlar bags) in the fasting and postprandial conditions were compared with BG levels and glycated hemoglobin (HbA1c) levels taken at the same time in 30 volunteers (13 healthy and 17 diabetic subjects). The mean sensor responses of the diabetic subjects as obtained by offline analysis were 1.1 times higher than those of the healthy subjects. The optimal regression equation framed with the significant correlating variables for HbA1c estimation achieved an accuracy of 66.67%. The online breath analysis by on/off binary prototype exhibited an accuracy of 60.51%. Though there exists a minimal uncertainty in classification, the on/off type portable prototype is easy to operate, gives a quicker response with a refresh/recovery rate of 19 s and can be used for preliminary diagnosis, and can be used for preliminary diagnosis. This inexpensive sensor technology may revolutionize personalized medicine in the near future and greatly benefit the underprivileged.
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Affiliation(s)
- Ramji Kalidoss
- Department of Biomedical Engineering, SRM Institute of Science & Technology, Tamil Nadu, 603203, India
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Guo H. Comparisons of combined oxidant capacity and redox-weighted oxidant capacity in their association with increasing levels of FeNO. CHEMOSPHERE 2018; 211:584-590. [PMID: 30096571 DOI: 10.1016/j.chemosphere.2018.07.191] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2018] [Revised: 07/04/2018] [Accepted: 07/31/2018] [Indexed: 06/08/2023]
Abstract
BACKGROUND Some ozone (O3) and nitrogen dioxides (NO2) health effects studies use Ox (sum value) as a surrogate. However, little is known about how this related to Oxwt (weighted value). OBJECTIVE We investigated the effects of redox-weighted oxidant capacity (Oxwt) on fractional exhaled nitric oxide (FeNO), a biomarker of airway inflammation, in a set of chronic obstructive pulmonary disease (COPD) patients. We also compare combined oxidant capacity (Ox) and Oxwt in their associations with increasing levels of FeNO. METHODS We measured FeNO values in 600 participants who have COPD at Shanghai Pulmonary Hospital. Ox was calculated directly by the sum of O3 and NO2. The redox-weighted oxidant capacity was calculated by denoting Oxwt as the weighted average of redox potentials. We applied generalized additive models (GAM) to investigate the impacts of Ox and Oxwt on FeNO levels, respectively. We fitted the same models for the influence of O3 and NO2 individually and jointly on FeNO levels to compare the result of Ox and Oxwt. RESULTS Oxwt were significantly linked with FeNO levels. The impact was robustest in current day after exposure, and were closely linked with the adjustment of PM2.5. A 10 μg m-3 increase in average Oxwt concentrations was linked to 0.88 (95% CI: -1.46, 3.28) increase, whereas a 10 μg m-3 increase in average Ox concentration was linked to 0.62 (95% CI: -0.79, 2.07) increase in FeNO. In two-pollutant models, an increase of 10 μg m-3 in average O3 concentrations with adjustment of NO2 was associated with 0.57 (95% CI: -1.26, 2.01) increase in FeNO. The impact estimates of Ox and Oxwt were statistically significant among males, non-smoking and elders who age above 65 years old. CONCLUSIONS This analysis demonstrated that Oxwt is used as a better indicator of atmospheric oxidative capacity as a proxy of O3 and NO2 in further epidemiological studies.
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Affiliation(s)
- Huibin Guo
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200438, China.
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Zhang Y, Salam MT, Berhane K, Eckel SP, Rappaport EB, Linn WS, Habre R, Bastain TM, Gilliland FD. Genetic and epigenetic susceptibility of airway inflammation to PM 2.5 in school children: new insights from quantile regression. Environ Health 2017; 16:88. [PMID: 28821285 PMCID: PMC5563051 DOI: 10.1186/s12940-017-0285-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2017] [Accepted: 07/11/2017] [Indexed: 05/16/2023]
Abstract
BACKGROUND The fractional concentration of exhaled nitric oxide (FeNO) is a biomarker of airway inflammation that has proved to be useful in investigations of genetic and epigenetic airway susceptibility to ambient air pollutants. For example, susceptibility to airway inflammation from exposure to particulate matter with aerodynamic diameter < =2.5 μm (PM2.5) varies by haplotypes and promoter region methylation in inducible nitric oxide synthase (iNOS encoded by NOS2). We hypothesized that PM2.5 susceptibility associated with these epigenetic and genetic variants may be greater in children with high FeNO from inflamed airways. In this study, we investigated genetic and epigenetic susceptibility to airborne particulate matter by examining whether the joint effects of PM2.5, NOS2 haplotypes and iNOS promoter methylation significantly vary across the distribution of FeNO in school children. METHODS The study included 940 school children in the southern California Children's Health Study who provided concurrent buccal samples and FeNO measurements. We used quantile regression to examine susceptibility by estimating the quantile-specific joint effects of PM2.5, NOS2 haplotype and methylation on FeNO. RESULTS We discovered striking differences in susceptibility to PM2.5 in school children. The joint effects of short-term PM2.5 exposure, NOS2 haplotypes and methylation across the FeNO distribution were significantly larger in the upper tail of the FeNO distribution, with little association in its lower tail, especially among children with asthma and Hispanic white children. CONCLUSION School-aged children with higher FeNO have greater genetic and epigenetic susceptibility to PM2.5, highlighting the importance of investigating effects across the entire distribution of FeNO.
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Affiliation(s)
- Yue Zhang
- Division of Epidemiology, Department of Internal Medicine, University of Utah, 295 Chipeta Way, Salt Lake City, UT 84018 USA
- Department of Family and Preventive Medicine, University of Utah, Salt Lake City, UT USA
- Veteran Affairs Salt Lake City Health Care System, Salt Lake City, UT USA
| | - Muhammad T. Salam
- Department of Preventive Medicine, University of Southern California, Los Angeles, CA USA
- Department of Psychiatry, Kern Medical, Bakersfield, CA USA
| | - Kiros Berhane
- Department of Preventive Medicine, University of Southern California, Los Angeles, CA USA
| | - Sandrah P. Eckel
- Department of Preventive Medicine, University of Southern California, Los Angeles, CA USA
| | - Edward B. Rappaport
- Department of Preventive Medicine, University of Southern California, Los Angeles, CA USA
| | - William S. Linn
- Department of Preventive Medicine, University of Southern California, Los Angeles, CA USA
| | - Rima Habre
- Department of Preventive Medicine, University of Southern California, Los Angeles, CA USA
| | - Theresa M. Bastain
- Department of Preventive Medicine, University of Southern California, Los Angeles, CA USA
| | - Frank D. Gilliland
- Department of Preventive Medicine, University of Southern California, Los Angeles, CA USA
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Eckel SP, Zhang Z, Habre R, Rappaport EB, Linn WS, Berhane K, Zhang Y, Bastain TM, Gilliland FD. Traffic-related air pollution and alveolar nitric oxide in southern California children. Eur Respir J 2016; 47:1348-56. [PMID: 26797034 DOI: 10.1183/13993003.01176-2015] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Accepted: 11/22/2015] [Indexed: 11/05/2022]
Abstract
Mechanisms for the adverse respiratory effects of traffic-related air pollution (TRAP) have yet to be established. We evaluated the acute effects of TRAP exposure on proximal and distal airway inflammation by relating indoor nitric oxide (NO), a marker of TRAP exposure in the indoor microenvironment, to airway and alveolar sources of exhaled nitric oxide (FeNO).FeNO was collected online at four flow rates in 1635 schoolchildren (aged 12-15 years) in southern California (USA) breathing NO-free air. Indoor NO was sampled hourly and linearly interpolated to the time of the FeNO test. Estimated parameters quantifying airway wall diffusivity (DawNO) and flux (J'awNO) and alveolar concentration (CANO) sources of FeNO were related to exposure using linear regression to adjust for potential confounders.We found that TRAP exposure indoors was associated with elevated alveolar NO. A 10 ppb higher indoor NO concentration at the time of the FeNO test was associated with 0.10 ppb higher average CANO (95% CI 0.04-0.16) (equivalent to a 7.1% increase from the mean), 4.0% higher J'awNO (95% CI -2.8-11.3) and 0.2% lower DawNO (95% CI -4.8-4.6).These findings are consistent with an airway response to TRAP exposure that was most marked in the distal airways.
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Affiliation(s)
- Sandrah P Eckel
- Dept of Preventive Medicine, University of Southern California, Los Angeles, CA, USA
| | - Zilu Zhang
- Dept of Preventive Medicine, University of Southern California, Los Angeles, CA, USA
| | - Rima Habre
- Dept of Preventive Medicine, University of Southern California, Los Angeles, CA, USA
| | - Edward B Rappaport
- Dept of Preventive Medicine, University of Southern California, Los Angeles, CA, USA
| | - William S Linn
- Dept of Preventive Medicine, University of Southern California, Los Angeles, CA, USA
| | - Kiros Berhane
- Dept of Preventive Medicine, University of Southern California, Los Angeles, CA, USA
| | - Yue Zhang
- Dept of Internal Medicine, University of Utah, Salt Lake City, UT, USA
| | - Theresa M Bastain
- Dept of Preventive Medicine, University of Southern California, Los Angeles, CA, USA
| | - Frank D Gilliland
- Dept of Preventive Medicine, University of Southern California, Los Angeles, CA, USA
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Inducible Nitric Oxide Synthase Promoter Haplotypes and Residential Traffic-Related Air Pollution Jointly Influence Exhaled Nitric Oxide Level in Children. PLoS One 2015; 10:e0145363. [PMID: 26714306 PMCID: PMC4695093 DOI: 10.1371/journal.pone.0145363] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Accepted: 12/01/2015] [Indexed: 01/03/2023] Open
Abstract
BACKGROUND Exhaled nitric oxide (FeNO), a biomarker of airway inflammation, predicts asthma risk in children. We previously found that the promoter haplotypes in inducible nitric oxide synthase (NOS2) and exposure to residential traffic independently influence FeNO level. Because NOS2 is inducible by environmental exposures such as traffic-related exposure, we tested the hypothesis that common NOS2 promoter haplotypes modulate the relationship between residential traffic-related exposure and FeNO level in children. METHODS In a cross-sectional population-based study, subjects (N = 2,457; 7-11 year-old) were Hispanic and non-Hispanic white children who participated in the Southern California Children's Health Study and had FeNO measurements. For residential traffic, lengths of local roads within circular buffers (50m, 100m and 200m radii around homes) around the subjects' homes were estimated using geographic information system (GIS) methods. We interrogated the two most common NOS2 promoter haplotypes that were found to affect FeNO level. RESULTS The relationship between local road lengths within 100m and 200m circular buffers and FeNO level varied significantly by one of the NOS2 promoter haplotypes (P-values for interaction between road length and NOS2 promoter haplotype = 0.02 and 0.03, respectively). In children who had ≤250m of local road lengths within 100m buffer around their homes, those with two copies of the haplotype had significantly lower FeNO (adjusted geometric mean = 11.74ppb; 95% confidence intervals (CI): 9.99 to 13.80) than those with no copies (adjusted geometric mean = 15.28ppb; 95% CI: 14.04 to 16.63) with statistically significant trend of lower FeNO level with increasing number of haplotype copy (P-value for trend = 0.002). In contrast, among children who had >250m of local road lengths within 100m buffer, FeNO level did not significantly differ by the haplotype copy-number (P-value for trend = 0.34). Similar interactive effects of this haplotype and local road lengths within 200m buffer on FeNO were also observed. CONCLUSIONS Higher exposure from residential traffic nullifies the protective effect of one common NOS2 promoter haplotype on FeNO level. Regulation of traffic-related pollution may protect children's respiratory health.
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Chen Z, Salam MT, Eckel SP, Breton CV, Gilliland FD. Chronic effects of air pollution on respiratory health in Southern California children: findings from the Southern California Children's Health Study. J Thorac Dis 2015; 7:46-58. [PMID: 25694817 DOI: 10.3978/j.issn.2072-1439.2014.12.20] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Accepted: 11/20/2014] [Indexed: 01/05/2023]
Abstract
Outdoor air pollution is one of the leading contributors to adverse respiratory health outcomes in urban areas around the world. Children are highly sensitive to the adverse effects of air pollution due to their rapidly growing lungs, incomplete immune and metabolic functions, patterns of ventilation and high levels of outdoor activity. The Children's Health Study (CHS) is a continuing series of longitudinal studies that first began in 1993 and has focused on demonstrating the chronic impacts of air pollution on respiratory illnesses from early childhood through adolescence. A large body of evidence from the CHS has documented that exposures to both regional ambient air and traffic-related pollutants are associated with increased asthma prevalence, new-onset asthma, risk of bronchitis and wheezing, deficits of lung function growth, and airway inflammation. These associations may be modulated by key genes involved in oxidative-nitrosative stress pathways via gene-environment interactions. Despite successful efforts to reduce pollution over the past 40 years, air pollution at the current levels still brings many challenges to public health. To further ameliorate adverse health effects attributable to air pollution, many more toxic pollutants may require regulation and control of motor vehicle emissions and other combustion sources may need to be strengthened. Individual interventions based on personal susceptibility may be needed to protect children's health while control measures are being implemented.
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Affiliation(s)
- Zhanghua Chen
- 1 Department of Preventive Medicine, Division of Environmental Health, 2 Department of Preventive Medicine, Division of Biostatistics, Keck School of Medicine, University of Southern California, Los Angeles, CA 90032, USA
| | - Muhammad T Salam
- 1 Department of Preventive Medicine, Division of Environmental Health, 2 Department of Preventive Medicine, Division of Biostatistics, Keck School of Medicine, University of Southern California, Los Angeles, CA 90032, USA
| | - Sandrah P Eckel
- 1 Department of Preventive Medicine, Division of Environmental Health, 2 Department of Preventive Medicine, Division of Biostatistics, Keck School of Medicine, University of Southern California, Los Angeles, CA 90032, USA
| | - Carrie V Breton
- 1 Department of Preventive Medicine, Division of Environmental Health, 2 Department of Preventive Medicine, Division of Biostatistics, Keck School of Medicine, University of Southern California, Los Angeles, CA 90032, USA
| | - Frank D Gilliland
- 1 Department of Preventive Medicine, Division of Environmental Health, 2 Department of Preventive Medicine, Division of Biostatistics, Keck School of Medicine, University of Southern California, Los Angeles, CA 90032, USA
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Berhane K, Zhang Y, Salam MT, Eckel SP, Linn WS, Rappaport EB, Bastain TM, Lurmann F, Gilliland FD. Longitudinal effects of air pollution on exhaled nitric oxide: the Children's Health Study. Occup Environ Med 2014; 71:507-13. [PMID: 24696513 DOI: 10.1136/oemed-2013-101874] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
OBJECTIVES To assess the effects of long-term variations in ambient air pollutants on longitudinal changes in exhaled nitric oxide (FeNO), a potentially useful biomarker of eosinophilic airway inflammation, based on data from the southern California Children's Health Study. METHODS Based on a cohort of 1211 schoolchildren from eight Southern California communities with FeNO measurements in 2006-2007 and 2007-2008, regression models adjusted for short-term effects of air pollution were fitted to assess the association between changes in annual long-term exposures and changes in FeNO. RESULTS Increases in annual average concentrations of 24-h average NO2 and PM2.5 (scaled to the IQR of 1.8 ppb and 2.4 μg/m(3), respectively) were associated with a 2.29 ppb (CI 0.36 to 4.21; p=0.02) and a 4.94 ppb (CI 1.44 to 8.47; p=0.005) increase in FeNO, respectively, after adjustments for short-term effects of the respective pollutants. In contrast, changes in annual averages of PM10 and O3 were not significantly associated with changes in FeNO. These findings did not differ significantly by asthma status. CONCLUSIONS Changes in annual average exposure to current levels of ambient air pollutants are significantly associated with changes in FeNO levels in children, independent of short-term exposures and asthma status. Use of this biomarker in population-based epidemiological research has great potential for assessing the impact of changing real world mixtures of ambient air pollutants on children's respiratory health.
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Affiliation(s)
- Kiros Berhane
- Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Yue Zhang
- University of Utah, Salt Lake City, Utah, USA
| | - Muhammad T Salam
- Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Sandrah P Eckel
- Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - William S Linn
- Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Edward B Rappaport
- Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Theresa M Bastain
- Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Fred Lurmann
- Sonoma Technology Inc., Petaluma, California, USA
| | - Frank D Gilliland
- Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
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Eckel SP, Linn WS, Berhane K, Rappaport EB, Salam MT, Zhang Y, Gilliland FD. Estimation of parameters in the two-compartment model for exhaled nitric oxide. PLoS One 2014; 9:e85471. [PMID: 24465571 PMCID: PMC3894971 DOI: 10.1371/journal.pone.0085471] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Accepted: 11/27/2013] [Indexed: 01/13/2023] Open
Abstract
The fractional concentration of exhaled nitric oxide (FeNO) is a biomarker of airway inflammation that is being increasingly considered in clinical, occupational, and epidemiological applications ranging from asthma management to the detection of air pollution health effects. FeNO depends strongly on exhalation flow rate. This dependency has allowed for the development of mathematical models whose parameters quantify airway and alveolar compartment contributions to FeNO. Numerous methods have been proposed to estimate these parameters using FeNO measured at multiple flow rates. These methods—which allow for non-invasive assessment of localized airway inflammation—have the potential to provide important insights on inflammatory mechanisms. However, different estimation methods produce different results and a serious barrier to progress in this field is the lack of a single recommended method. With the goal of resolving this methodological problem, we have developed a unifying framework in which to present a comprehensive set of existing and novel statistical methods for estimating parameters in the simple two-compartment model. We compared statistical properties of the estimators in simulation studies and investigated model fit and parameter estimate sensitivity across methods using data from 1507 schoolchildren from the Southern California Children's Health Study, one of the largest multiple flow FeNO studies to date. We recommend a novel nonlinear least squares model with natural log transformation on both sides that produced estimators with good properties, satisfied model assumptions, and fit the Children's Health Study data well.
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Affiliation(s)
- Sandrah P. Eckel
- Department of Preventive Medicine, University of Southern California, Los Angeles, California, United States of America
- * E-mail:
| | - William S. Linn
- Department of Preventive Medicine, University of Southern California, Los Angeles, California, United States of America
| | - Kiros Berhane
- Department of Preventive Medicine, University of Southern California, Los Angeles, California, United States of America
| | - Edward B. Rappaport
- Department of Preventive Medicine, University of Southern California, Los Angeles, California, United States of America
| | - Muhammad T. Salam
- Department of Preventive Medicine, University of Southern California, Los Angeles, California, United States of America
| | - Yue Zhang
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah, United States of America
| | - Frank D. Gilliland
- Department of Preventive Medicine, University of Southern California, Los Angeles, California, United States of America
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van der Valk RJP, Caudri D, Savenije O, Koppelman GH, Smit HA, Wijga AH, Postma DS, Kerkhof M, Brunekreef B, de Jongste JC. Childhood wheezing phenotypes and FeNO in atopic children at age 8. Clin Exp Allergy 2013; 42:1329-36. [PMID: 22925319 DOI: 10.1111/j.1365-2222.2012.04010.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Fractional exhaled Nitric Oxide (FeNO) is a surrogate biomarker of the degree of eosinophilic airway inflammation. Using longitudinal latent class analysis, five wheezing phenotypes have been identified, characterized by different ages of onset and prognosis. OBJECTIVES To assess FeNO measured at 4 and 8 years in children with different phenotypes of wheeze and atopy. METHODS Children participated in the Prevention and Incidence of Asthma and Mite Allergy (PIAMA) study, a prospective birth cohort in the Netherlands. Respiratory health was assessed yearly by questionnaires until the age of 8 years; these data were used to identify five wheezing phenotypes. Associations between FeNO and wheezing phenotypes were investigated using weighted linear regression. RESULTS Data on wheezing phenotypes and FeNO at 4 and 8 years were available in 588 and 973 children respectively. Compared with the phenotype of never and transient wheeze, FeNO at 4 years was higher in intermediate onset and persistent wheeze. FeNO at 8 years of age differed significantly between all phenotypes, with highest FeNO values for persistent, intermediate onset, and late onset wheeze. Rise in FeNO from 4 to 8 years in intermediate and late onset wheezers was significantly higher compared to FeNO rise in never and transient wheezers. Stratified analyses showed that the increase in FeNO in persistent, intermediate, and late onset wheeze was only present in children with allergic sensitization at 8 years. CONCLUSIONS AND CLINICAL RELEVANCE The FeNO measured at 8 years was associated with specific wheezing phenotypes, only among atopic children.
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Affiliation(s)
- R J P van der Valk
- Department of Pediatrics, Erasmus University Medical Center, Sophia Children's Hospital, Rotterdam, The Netherlands
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13
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Yoda Y, Otani N, Hasunuma H, Kanegae H, Shima M. Storage conditions for stability of offline measurement of fractional exhaled nitric oxide after collection for epidemiologic research. BMC Pulm Med 2012; 12:68. [PMID: 23116255 PMCID: PMC3515473 DOI: 10.1186/1471-2466-12-68] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2012] [Accepted: 10/29/2012] [Indexed: 11/18/2022] Open
Abstract
Background The measurement of fractional concentration of nitric oxide in exhaled air (FeNO) is valuable for the assessment of airway inflammation. Offline measurement of FeNO has been used in some epidemiologic studies. However, the time course of the changes in FeNO after collection has not been fully clarified. In this study, the effects of storage conditions on the stability of FeNO measurement in exhaled air after collection for epidemiologic research were examined. Methods Exhaled air samples were collected from 48 healthy adults (mean age 43.4 ± 12.1 years) in Mylar bags. FeNO levels in the bags were measured immediately after collection. The bags were then stored at 4°C or room temperature to measure FeNO levels repeatedly for up to 168 hours. Results In the bags stored at room temperature after collection, FeNO levels were stable for 9 hours, but increased starting at 24 hours. FeNO levels remained stable for a long time at 4°C, and they were 99.7% ± 7.7% and 101.3% ± 15.0% relative to the baseline values at 24 and 96 hours, respectively. When the samples were stored at 4°C, FeNO levels gradually decreased with time among the subjects with FeNO ≥ 51 ppb immediately after collection, although there were almost no changes among the other subjects. FeNO levels among current smokers increased even at 4°C, although the values among ex-smokers decreased gradually, and those among nonsmokers remained stable. The rate of increase was significantly higher among current smokers than among nonsmokers and ex-smokers from 9 hours after collection onwards. Conclusions Storage at 4°C could prolong the stability of FeNO levels after collection. This result suggests that valid measurements can be performed within several days if the samples are stored at 4°C. However, the time course of the changes in FeNO levels differed in relation to initial FeNO values and cigarette smoking.
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Affiliation(s)
- Yoshiko Yoda
- Department of Public Health, Hyogo College of Medicine, Mukogawa-cho, Nishinomiya, Hyogo, Japan
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14
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Cornell AG, Chillrud SN, Mellins RB, Acosta LM, Miller RL, Quinn JW, Yan B, Divjan A, Olmedo OE, Lopez-Pintado S, Kinney PL, Perera FP, Jacobson JS, Goldstein IF, Rundle AG, Perzanowski MS. Domestic airborne black carbon and exhaled nitric oxide in children in NYC. JOURNAL OF EXPOSURE SCIENCE & ENVIRONMENTAL EPIDEMIOLOGY 2012; 22:258-66. [PMID: 22377682 PMCID: PMC3685864 DOI: 10.1038/jes.2012.3] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2011] [Accepted: 09/23/2011] [Indexed: 05/21/2023]
Abstract
Differential exposure to combustion by-products and allergens may partially explain the marked disparity in asthma prevalence (3-18%) among New York City neighborhoods. Subclinical changes in airway inflammation can be measured by fractional exhaled nitric oxide (FeNO). FeNO could be used to test independent effects of these environmental exposures on airway inflammation. Seven- and eight-year-old children from neighborhoods with lower (range 3-9%, n=119) and higher (range 11-18%, n=121) asthma prevalence participated in an asthma case-control study. During home visits, FeNO was measured, and samples of bed dust (allergens) and air (black carbon; BC) were collected. Neighborhood built-environment characteristics were assessed for the 500 m surrounding participants' homes. Airborne BC concentrations in homes correlated with neighborhood asthma prevalence (P<0.001) and neighborhood densities of truck routes (P<0.001) and buildings burning residual oil (P<0.001). FeNO concentrations were higher among asthmatics with than in those without frequent wheeze (≥4 times/year) (P=0.002). FeNO concentrations correlated with domestic BC among children without seroatopy (P=0.012) and with dust mite allergen among children with seroatopy (P=0.020). The association between airborne BC in homes and both neighborhood asthma prevalence and FeNO suggest that further public health interventions on truck emissions standards and residual oil use are warranted.
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Affiliation(s)
- Alexandra G. Cornell
- Department of Pediatrics, Columbia University College of Physicians and Surgeons, New York, NY
| | - Steven N. Chillrud
- Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY
- Columbia Center for Children’s Environmental Health, Columbia University, New York, NY
| | - Robert B. Mellins
- Department of Pediatrics, Columbia University College of Physicians and Surgeons, New York, NY
| | - Luis M. Acosta
- Columbia Center for Children’s Environmental Health, Columbia University, New York, NY
| | - Rachel L. Miller
- Department of Pediatrics, Columbia University College of Physicians and Surgeons, New York, NY
- Columbia Center for Children’s Environmental Health, Columbia University, New York, NY
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, NY
- Division of Pulmonary, Allergy, Critical Care Medicine, Department of Medicine, Columbia University College of Physicians and Surgeons, New York, NY
| | - James W. Quinn
- Institute for Social and Economic Research and Policy, Columbia University, New York, NY
| | - Beizhan Yan
- Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY
| | - Adnan Divjan
- Columbia Center for Children’s Environmental Health, Columbia University, New York, NY
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, NY
| | - Omar E. Olmedo
- Columbia Center for Children’s Environmental Health, Columbia University, New York, NY
| | - Sara Lopez-Pintado
- Department of Biostatistics, Mailman School of Public Health, Columbia University, New York, NY
| | - Patrick L. Kinney
- Columbia Center for Children’s Environmental Health, Columbia University, New York, NY
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, NY
| | - Frederica P. Perera
- Columbia Center for Children’s Environmental Health, Columbia University, New York, NY
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, NY
| | - Judith S. Jacobson
- Department of Epidemiology, Mailman School of Public Health, Columbia University, New York, NY
| | - Inge F. Goldstein
- Columbia Center for Children’s Environmental Health, Columbia University, New York, NY
- Department of Epidemiology, Mailman School of Public Health, Columbia University, New York, NY
| | - Andrew G. Rundle
- Columbia Center for Children’s Environmental Health, Columbia University, New York, NY
- Department of Epidemiology, Mailman School of Public Health, Columbia University, New York, NY
| | - Matthew S. Perzanowski
- Columbia Center for Children’s Environmental Health, Columbia University, New York, NY
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, NY
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15
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Genetic and epigenetic variations in inducible nitric oxide synthase promoter, particulate pollution, and exhaled nitric oxide levels in children. J Allergy Clin Immunol 2011; 129:232-9.e1-7. [PMID: 22055874 DOI: 10.1016/j.jaci.2011.09.037] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2011] [Revised: 08/11/2011] [Accepted: 09/29/2011] [Indexed: 02/07/2023]
Abstract
BACKGROUND Inducible nitric oxide synthase (iNOS; encoded by nitric oxide synthase isoform 2 [NOS2]) is the major enzyme for nitric oxide synthesis in airways. As such, measurement of fractional concentration of exhaled nitric oxide (Feno) provides an in vivo assessment of iNOS activity. Short-term exposure to air pollution, haplotypes, and DNA methylation in the NOS2 promoter has been associated independently with iNOS expression, Feno levels, or both. OBJECTIVE We aimed to examine the effects of ambient air pollutants, NOS2 promoter haplotypes, and NOS2 promoter methylation on Feno levels in children. METHODS We selected 940 participants in the Children's Health Study who provided buccal samples and had undergone Feno measurement on the same day. DNA methylation was measured with a bisulfite-PCR Pyrosequencing assay. Seven single nucleotide polymorphisms captured the haplotype diversity in the NOS2 promoter. Average particulate matter with an aerodynamic diameter of 2.5 μm or less (PM(2.5)) and 10 μm (PM(10)) or less and ozone and nitrogen dioxide levels 7 days before Feno measurement were estimated based on air pollution data obtained at central monitoring sites. RESULTS We found interrelated effects of PM(2.5), NOS2 promoter haplotypes, and iNOS methylation on Feno levels. Increased 7-day average PM(2.5) exposure was associated with lower iNOS methylation (P = .01). NOS2 promoter haplotypes were globally associated with NOS2 promoter methylation (P = 6.2 × 10(-8)). There was interaction among 1 common promoter haplotype, iNOS methylation level, and PM(2.5) exposure on Feno levels (P(interaction) = .00007). CONCLUSION Promoter variants in NOS2 and short-term PM(2.5) exposure affect iNOS methylation. This is one of the first studies showing contributions of genetic and epigenetic variations in air pollution-mediated phenotype expression.
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Eckel SP, Berhane K, Salam MT, Rappaport EB, Linn WS, Bastain TM, Zhang Y, Lurmann F, Avol EL, Gilliland FD. Residential traffic-related pollution exposures and exhaled nitric oxide in the children's health study. ENVIRONMENTAL HEALTH PERSPECTIVES 2011; 119:1472-7. [PMID: 21708511 PMCID: PMC3230449 DOI: 10.1289/ehp.1103516] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2011] [Accepted: 06/27/2011] [Indexed: 05/05/2023]
Abstract
BACKGROUND The fractional concentration of nitric oxide in exhaled air (FeNO) potentially detects airway inflammation related to air pollution exposure. Existing studies have not yet provided conclusive evidence on the association of FeNO with traffic-related pollution (TRP). OBJECTIVES We evaluated the association of FeNO with residential TRP exposure in a large cohort of children. METHODS We related FeNO measured on 2,143 children (ages 7-11 years) who participated in the Southern California Children's Health Study (CHS) to five classes of metrics of residential TRP: distances to freeways and major roads; length of all and local roads within circular buffers around the home; traffic densities within buffers; annual average line source dispersion modeled nitrogen oxides (NOx) from freeways and nonfreeway roads; and predicted annual average nitrogen oxide, nitrogen dioxide, and NOx from a model based on intracommunity sampling in the CHS. RESULTS In children with asthma, length of roads was positively associated with FeNO, with stronger associations in smaller buffers [46.7%; 95% confidence interval (CI), 14.3-88.4], 12.4% (95% CI, -8.8 to 38.4), and 4.1% (95% CI, -14.6 to 26.8) higher FeNO for 100-, 300-, and 1,000-m increases in the length of all roads in 50-, 100-, and 200-m buffers, respectively. Other TRP metrics were not significantly associated with FeNO, even though the study design was powered to detect exposures explaining as little as 0.4% of the variation in natural log-transformed FeNO (R2 = 0.004). CONCLUSION Length of road was the only indicator of residential TRP exposure associated with airway inflammation in children with asthma, as measured by FeNO.
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Affiliation(s)
- Sandrah P Eckel
- University of Southern California, Los Angeles, California, USA.
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17
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Breton CV, Byun HM, Wang X, Salam MT, Siegmund K, Gilliland FD. DNA methylation in the arginase-nitric oxide synthase pathway is associated with exhaled nitric oxide in children with asthma. Am J Respir Crit Care Med 2011; 184:191-7. [PMID: 21512169 DOI: 10.1164/rccm.201012-2029oc] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
RATIONALE Genetic variation in arginase (ARG) and nitric oxide synthase (NOS) has been associated with exhaled nitric oxide (FeNO) levels in children. Little is known about whether epigenetic variation in these genes modulates FeNO. OBJECTIVES To evaluate whether DNA methylation in ARG and NOS genes is associated with FeNO. METHODS A subset of 940 participants in the Children's Health Study were selected for this study. Children were eligible if they had FeNO measurements and buccal cells collected on the same day. CpG loci located in the promoter regions of NOS1, NOS2A, NOS3, ARG1, and ARG2 genes were analyzed. Multiple loci in each gene were evaluated individually and averaged together. DNA methylation was measured using a bisulfite-polymerase chain reaction pyrosequencing assay. Linear regression models were used to investigate the association between DNA methylation and FeNO and whether associations differed by asthma status. MEASUREMENTS AND MAIN RESULTS DNA methylation in ARG2 was significantly associated with FeNO. A 1% increase in average DNA methylation of ARG2 was associated with a 2.3% decrease in FeNO (95% confidence interval, -4 to -0.6). This association was significantly larger in children with asthma (%diff = -8.7%) than in children with no asthma (%diff = -1.6%; p(int) = 0.01). Differences in FeNO by asthma status were also observed for ARG1 (%diff(asthma) = -4.4%; %diff(non-asthma) = 0.3%; p(int) = 0.02). DNA methylation in NOS genes was not associated with FeNO. CONCLUSIONS DNA methylation in ARG1 and ARG2 is associated with FeNO in children with asthma and suggests a possible role for epigenetic regulation of nitric oxide production.
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Affiliation(s)
- Carrie V Breton
- Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA.
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18
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Salam MT, Bastain TM, Rappaport EB, Islam T, Berhane K, Gauderman WJ, Gilliland FD. Genetic variations in nitric oxide synthase and arginase influence exhaled nitric oxide levels in children. Allergy 2011; 66:412-9. [PMID: 21039601 DOI: 10.1111/j.1398-9995.2010.02492.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
BACKGROUND Exhaled nitric oxide (FeNO) is a biomarker of airway inflammation. In the nitric oxide (NO) synthesis pathway, nitric oxide synthases (encoded by NOS1, NOS2A, and NOS3) and arginases (encoded by ARG1 and ARG2) compete for L-arginine. Although FeNO levels are higher in children with asthma/allergy, influence of these conditions on the relationships between variations in these genes and FeNO remains unknown. The aims of the study were to evaluate the role of genetic variations in nitric oxide synthases and arginases on FeNO in children and to assess the influence of asthma and respiratory allergy on these genetic associations. METHODS Among children (6-11 years) who participated in the southern California Children's Health Study, variations in these five genetic loci were characterized by tagSNPs. FeNO was measured in two consecutive years (N = 2298 and 2515 in Years 1 and 2, respectively). Repeated measures analysis of variance was used to evaluate the associations between these genetic variants and FeNO. RESULTS Sequence variations in the NOS2A and ARG2 loci were globally associated with FeNO (P = 0.0002 and 0.01, respectively). The ARG2 association was tagged by intronic variant rs3742879 with stronger association with FeNO in asthmatic children (P-interaction = 0.01). The association of a NOS2A promoter haplotype with FeNO varied significantly by rs3742879 genotypes and by asthma. CONCLUSION Variants in the NO synthesis pathway genes jointly contribute to differences in FeNO concentrations. Some of these genetic influences were stronger in children with asthma. Further studies are required to confirm our findings.
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Affiliation(s)
- M T Salam
- Department of Preventive Medicine, University of Southern California Keck School of Medicine, Los Angeles, CA, USA
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19
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Perzanowski MS, Divjan A, Mellins RB, Canfield SM, Rosa MJ, Chew GL, Rundle A, Goldstein IF, Jacobson JS. Exhaled NO among inner-city children in New York City. J Asthma 2010; 47:1015-21. [PMID: 20936992 DOI: 10.3109/02770903.2010.513075] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND Fractional exhaled nitric oxide (FeNO) has been proposed as a biomarker of airway inflammation for cohort studies of asthma. OBJECTIVES To assess the association between FeNO and asthma symptoms among 7-year-old children living in an inner-city community. To test the association between environmental tobacco smoke (ETS) exposure (previous and current) and FeNO among these children. METHODS As part of a longitudinal study of asthma, children recruited in Head Start centers at age 4 had offline FeNO and lung function testing at age 7. Children with allergen-specific immunoglobulin E (IgE) (≥0.35 IU/mL) at age 7 were considered seroatopic. ETS exposure at ages 4 and 7 was assessed by questionnaire. RESULTS Of 144 participating children, 89 had complete questionnaire data and achieved valid FeNO and lung function tests. Children with reported wheeze in the previous 12 months (n = 19) had higher FeNO than those without wheeze (n = 70) (geometric means 17.0 vs. 11.0 ppb, p = .005). FeNO remained significantly associated with wheeze (p = .031), after adjusting for seroatopy and forced expiratory volume in 1 second (FEV₁) in multivariable regression. FeNO at age 7 was positively associated with domestic ETS exposure at age 4 (29%) (β = 0.36, p = .015) but inversely associated with ETS exposure at age 7 (16%) (β = -0.74, p < .001). CONCLUSIONS Given its association with current wheeze, independent of seroatopy and lung function, FeNO provides a relevant outcome measure for studies in inner-city communities. While compelling, the positive association between ETS exposure at age 4 and a marker of airway inflammation at age 7 should be confirmed in a larger study.
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Affiliation(s)
- Matthew S Perzanowski
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, NY 10032, USA.
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Berhane K, Zhang Y, Linn WS, Rappaport EB, Bastain TM, Salam MT, Islam T, Lurmann F, Gilliland FD. The effect of ambient air pollution on exhaled nitric oxide in the Children's Health Study. Eur Respir J 2010; 37:1029-36. [PMID: 20947676 DOI: 10.1183/09031936.00081410] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
We assessed the effect of daily variations in ambient air pollutants on exhaled nitric oxide fraction (F(eNO)) using data from a cohort of school children with large differences in air pollutant exposures from the Children's Health Study. Based on a cohort of 2,240 school children from 13 Southern Californian communities, cumulative lagged average regression models were fitted to determine the association between F(eNO) and ambient air pollution levels from central site monitors with lags of up to 30 days prior to F(eNO) testing. Daily 24-h cumulative lagged averages of particles with a 50% cut-off aerodynamic diameter of 2.5 µm (PM₂.₅; over 1-8 days) and particles with a 50% cut-off aerodynamic diameter of 10 µm (PM₁₀; over 1-7 days), as well as 10:00-18:00 h cumulative lagged average of O₃ (over 1-23 days) were significantly associated with 17.42% (p<0.01), 9.25% (p<0.05) and 14.25% (p<0.01) higher F(eNO) levels over the interquartile range of 7.5 μg·m⁻³, 12.97 μg·m⁻³ and 15.42 ppb, respectively. The effects of PM₂.₅, PM₁₀ and O₃ were higher in the warm season. The particulate matter effects were robust to adjustments for effects of O₃ and temperature and did not vary by asthma or allergy status. In summary, short-term increases in PM₂.₅, PM₁₀ and O₃ were associated with airway inflammation independent of asthma and allergy status, with PM₁₀ effects significantly higher in the warm season.
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Affiliation(s)
- K Berhane
- Dept of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089-9011, USA.
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Bastain TM, Islam T, Berhane KT, McConnell RS, Rappaport EB, Salam MT, Linn WS, Avol EL, Zhang Y, Gilliland FD. Exhaled nitric oxide, susceptibility and new-onset asthma in the Children's Health Study. Eur Respir J 2010; 37:523-31. [PMID: 20634264 DOI: 10.1183/09031936.00021210] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
A substantial body of evidence suggests an aetiological role of inflammation, and oxidative and nitrosative stress in asthma pathogenesis. Exhaled nitric oxide fraction (F(eNO)) may provide a noninvasive marker of oxidative and nitrosative stress, and aspects of airway inflammation. We examined whether children with elevated F(eNO) are at increased risk for new-onset asthma. We prospectively followed 2,206 asthma-free children (age 7-10 yrs) who participated in the Children's Health Study. We measured F(eNO) and followed these children for 3 yrs to ascertain incident asthma cases. Cox proportional hazard models were fitted to examine the association between F(eNO) and new-onset asthma. We found that F(eNO) was associated with increased risk of new-onset asthma. Children in the highest F(eNO) quartile had more than a two-fold increased risk of new-onset asthma compared to those with the lowest quartile (hazard ratio 2.1, 95% CI 1.3-3.5). This effect did not vary with the child's history of respiratory allergic symptoms. However, the effect of elevated F(eNO) on new-onset asthma was most apparent among those without a parental history of asthma. Our results indicate that children with elevated F(eNO) are at increased risk for new-onset asthma, especially if they have no parental history of asthma.
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Affiliation(s)
- T M Bastain
- Dept of Preventive Medicine, Keck School of Medicine, 1540 Alcazar Street, CHP 236, Los Angeles, CA 90033, USA
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Linn WS, Berhane KT, Rappaport EB, Bastain TM, Avol EL, Gilliland FD. Relationships of online exhaled, offline exhaled, and ambient nitric oxide in an epidemiologic survey of schoolchildren. JOURNAL OF EXPOSURE SCIENCE & ENVIRONMENTAL EPIDEMIOLOGY 2009; 19:674-681. [PMID: 18941479 DOI: 10.1038/jes.2008.64] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2008] [Accepted: 09/15/2008] [Indexed: 05/26/2023]
Abstract
UNLABELLED Field measurements of exhaled nitric oxide (FeNO) and ambient nitric oxide (NO) are useful to assess both respiratory health and short-term air pollution exposure. Online real-time measurement maximizes data quality and comparability with clinical studies, but offline delayed measurement may be more practical for large epidemiological studies. To facilitate cross-comparison in larger studies, we measured FeNO and concurrent ambient NO both online and offline in 362 children at 14 schools in 8 Southern California communities. Offline breath samples were collected in bags at 100 ml/s expiratory flow with deadspace discard; online FeNO was measured at 50 ml/s. Scrubbing of ambient NO from inhaled air appeared to be nearly 100% effective online, but 50-75% effective offline. Offline samples were stored at 2-8 degrees C and analyzed 2-26 h later at a central laboratory. Offline and online FeNO showed a nearly (but not completely) linear relationship (R(2)=0.90); unadjusted means (ranges) were 10 (4-94) and 15 (3-181) p.p.b., respectively. Ambient NO concentration range was 0-212 p.p.b. Offline FeNO was positively related to ambient NO (r=0.30, P<0.0001), unlike online FeNO (r=0.09, P=0.08), indicating that ambient NO artifactually influenced offline measurements. Offline FeNO differed between schools (P<0.001); online FeNO did not (P=0.26), suggesting artifacts related to offline bag storage and transport. Artifact effects were small in comparison with between-subject variance of FeNO. An empirical statistical model predicting individual online FeNO from offline FeNO, ambient NO, and lag time before offline analysis gave R(2)=0.94. Analyses of school or age differences yielded similar results from measured or model-predicted online FeNO. CONCLUSIONS Either online or offline measurement of exhaled NO and concurrent ambient NO can be useful in field epidemiology. Influence of ambient NO on exhaled NO should be examined carefully, particularly for offline measurements.
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Affiliation(s)
- William S Linn
- Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California, USA.
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23
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Exhaled nitric oxide in a population-based study of southern California schoolchildren. Respir Res 2009; 10:28. [PMID: 19379527 PMCID: PMC2678086 DOI: 10.1186/1465-9921-10-28] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2008] [Accepted: 04/21/2009] [Indexed: 12/26/2022] Open
Abstract
Background Determinants of exhaled nitric oxide (FeNO) need to be understood better to maximize the value of FeNO measurement in clinical practice and research. Our aim was to identify significant predictors of FeNO in an initial cross-sectional survey of southern California schoolchildren, part of a larger longitudinal study of asthma incidence. Methods During one school year, we measured FeNO at 100 ml/sec flow, using a validated offline technique, in 2568 children of age 7–10 yr. We estimated online (50 ml/sec flow) FeNO using a prediction equation from a separate smaller study with adjustment for offline measurement artifacts, and analyzed its relationship to clinical and demographic characteristics. Results FeNO was lognormally distributed with geometric means ranging from 11 ppb in children without atopy or asthma to 16 ppb in children with allergic asthma. Although effects of atopy and asthma were highly significant, ranges of FeNO for children with and without those conditions overlapped substantially. FeNO was significantly higher in subjects aged > 9, compared to younger subjects. Asian-American boys showed significantly higher FeNO than children of all other sex/ethnic groups; Hispanics and African-Americans of both sexes averaged slightly higher than non-Hispanic whites. Increasing height-for-age had no significant effect, but increasing weight-for-height was associated with decreasing FeNO. Conclusion FeNO measured offline is a useful biomarker for airway inflammation in large population-based studies. Further investigation of age, ethnicity, body-size, and genetic influences is needed, since they may contribute to substantial variation in FeNO.
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