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Merianos AL, Jandarov RA, Cataletto M, Mahabee-Gittens EM. Tobacco smoke exposure and fractional exhaled nitric oxide levels among U.S. adolescents. Nitric Oxide 2021; 117:53-59. [PMID: 34688860 DOI: 10.1016/j.niox.2021.10.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 03/14/2021] [Accepted: 10/19/2021] [Indexed: 10/20/2022]
Abstract
BACKGROUND Fractional exhaled nitric oxide (FeNO) can objectively guide clinical practice in the assessment, diagnosis, and treatment of eosinophilic airway inflammation. FeNO values may be affected by current smoking, but the role of tobacco smoke exposure (TSE) is understudied. OBJECTIVE This study investigated the associations between biochemically validated and self-reported TSE and FeNO levels among U.S. nonsmoking adolescents without asthma. METHODS National Health and Nutrition Examination Survey 2007-2012 data were used. TSE was assessed via serum cotinine and self-reported measures. We assessed FeNO continuously and using cutpoints of >35 ppb and >50 ppb to indicate likely eosinophilic inflammation in children and adults, respectively. We conducted linear and logistic regression adjusting for potential covariates. RESULTS Overall, 34.0% of adolescents had low cotinine (0.05-2.99 ng/ml), 6.2% had high cotinine (≥3.00 ng/ml), and 11.9% had home TSE. Compared to adolescents with no/minimal cotinine, adolescents with high cotinine were at reduced odds to have FeNO >35 ppb (adjusted odds ratio [aOR] = 0.54, 95%CI = 0.43,0.69). Adolescents with low cotinine had lower FeNO values (β = -2.05, 95%CI = -3.61,-0.49), and were also at decreased odds to have FeNO >35 ppb (aOR = 0.74, 95%CI = 0.66,0.83) and FeNO >50 ppb (aOR = 0.62, 95%CI = 0.53,0.72). Adolescents with home TSE were at reduced odds to have FeNO >50 ppb (aOR = 0.72, 95%CI = 0.57,0.91) than adolescents without home TSE. Adolescents with a higher number of cigarettes/day smoked inside their home were at reduced odds to have FeNO >35 ppb (OR = 0.98, 95%CI = 0.97,0.99) and FeNO >50 ppb (OR = 0.98, 95%CI = 0.96,0.99). CONCLUSIONS TSE was associated with decreased FeNO levels. The addition of TSE may be clinically important when interpreting thresholds for FeNO.
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Affiliation(s)
- Ashley L Merianos
- School of Human Services, University of Cincinnati, Cincinnati, OH, USA.
| | - Roman A Jandarov
- Division of Biostatistics and Bioinformatics, Department of Environmental and Public Health Sciences, College of Medicine, University of Cincinnati, 162 Kettering Lab Building, 160 Panzeca Way, Cincinnati, OH, 45267-0056, USA.
| | - Mary Cataletto
- Department of Pediatrics, NYU Long Island School of Medicine, 222 Station Plaza North, Mineola, NY, 11501, USA.
| | - E Melinda Mahabee-Gittens
- Division of Emergency Medicine, Cincinnati Children's Hospital Medical Center, College of Medicine, University of Cincinnati, 3333 Burnet Avenue, MLC 2008, Cincinnati, OH, 45229, USA.
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Abstract
Asthma is the most common chronic disease among children. It cannot be prevented but can be controlled. Industrialized countries experience high lifetime asthma prevalence that has increased over recent decades. Asthma has a complex interplay of genetic and environmental triggers. Studies have revealed complex interactions of lung structure and function genes with environmental exposures such as environmental tobacco smoke and vitamin D. Home environmental strategies can reduce asthma morbidity in children but should be tailored to specific allergens. Coupled with education and severity-specific asthma therapy, tailored interventions may be the most effective strategy to manage childhood asthma.
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Affiliation(s)
- Jessica P Hollenbach
- Department of Pediatrics, Asthma Center, The Children's Center for Community Research, CT Children's Medical Center, University of Connecticut School of Medicine, 282 Washington Street, Hartford, CT 06106, USA
| | - Michelle M Cloutier
- Department of Pediatrics, Asthma Center, The Children's Center for Community Research, Connecticut Children's Medical Center, University of Connecticut Health Center, 282 Washington Street, Hartford, CT 06106, USA.
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Yang S, Park J, Lee YK, Kim H, Hahn YS. Association of longitudinal fractional exhaled nitric oxide measurements with asthma control in atopic children. Respir Med 2015; 109:572-9. [PMID: 25840483 DOI: 10.1016/j.rmed.2015.03.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2014] [Revised: 02/25/2015] [Accepted: 03/13/2015] [Indexed: 10/23/2022]
Abstract
OBJECTIVES We sought to determine whether longitudinal measurements of FeNO are informative for future loss of asthma control in children with atopic asthma. METHODS One hundred seventy-eight patients aged 8-16 years with atopic asthma were enrolled. FeNO and lung functions were serially monitored 10 times or more over 2 years when subjects were not receiving controller medications. After completion of monitoring, 1-year observation on the occurrence of loss of asthma control was performed and associations of loss of asthma control with spirometric and FeNO measurements were analyzed. RESULTS Loss of asthma control occurred during observation periods in 110 (76%) of 145 patients who completed the study. Of all monitored parameters including airway reactivity, the highest FeNO of serial measurements (H-FeNO) (adjusted odds ratio (aOR), 1.21; 95% CI, 1.08-1.36) and the rate of FeNO levels higher than 21 ppb (R21FeNO) (aOR, 1.06; 95% CI, 1.01-1.11) were the only independent predictors of upcoming control loss in the multiple logistic regression analysis. In receiver-operator characteristic curve analysis, H-FeNO > 37 ppb and R21FeNO > 20% demonstrated 91% and 88% sensitivity for a future loss of asthma control at the cost of low specificity (60% and 65%, respectively). In contrast, H-FeNO > 47 ppb and R21FeNO > 41% gave 96% and 88% specificity, but these sacrificed sensitivity to 70% and 72%, respectively. CONCLUSIONS Our data show that both amount and frequency of a FeNO increase during longitudinal monitoring are helpful in predicting asthma control status.
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Affiliation(s)
- Sohyoung Yang
- Department of Pediatrics, College of Medicine and Medical Research Institute, Chungbuk National University, Cheongju, Republic of Korea
| | - Joohyun Park
- Department of Pediatrics, College of Medicine and Medical Research Institute, Chungbuk National University, Cheongju, Republic of Korea
| | - Youn Kyung Lee
- Department of Pediatrics, College of Medicine and Medical Research Institute, Chungbuk National University, Cheongju, Republic of Korea
| | - Heon Kim
- Department of Preventive Medicine, College of Medicine and Medical Research Institute, Chungbuk National University, Cheongju, Republic of Korea
| | - Youn-Soo Hahn
- Department of Pediatrics, College of Medicine and Medical Research Institute, Chungbuk National University, Cheongju, Republic of Korea.
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Kanchongkittiphon W, Mendell MJ, Gaffin JM, Wang G, Phipatanakul W. Indoor environmental exposures and exacerbation of asthma: an update to the 2000 review by the Institute of Medicine. ENVIRONMENTAL HEALTH PERSPECTIVES 2015; 123:6-20. [PMID: 25303775 PMCID: PMC4286274 DOI: 10.1289/ehp.1307922] [Citation(s) in RCA: 243] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Accepted: 10/09/2014] [Indexed: 05/18/2023]
Abstract
BACKGROUND Previous research has found relationships between specific indoor environmental exposures and exacerbation of asthma. OBJECTIVES In this review we provide an updated summary of knowledge from the scientific literature on indoor exposures and exacerbation of asthma. METHODS Peer-reviewed articles published from 2000 to 2013 on indoor exposures and exacerbation of asthma were identified through PubMed, from reference lists, and from authors' files. Articles that focused on modifiable indoor exposures in relation to frequency or severity of exacerbation of asthma were selected for review. Research findings were reviewed and summarized with consideration of the strength of the evidence. RESULTS Sixty-nine eligible articles were included. Major changed conclusions include a causal relationship with exacerbation for indoor dampness or dampness-related agents (in children); associations with exacerbation for dampness or dampness-related agents (in adults), endotoxin, and environmental tobacco smoke (in preschool children); and limited or suggestive evidence for association with exacerbation for indoor culturable Penicillium or total fungi, nitrogen dioxide, rodents (nonoccupational), feather/down pillows (protective relative to synthetic bedding), and (regardless of specific sensitization) dust mite, cockroach, dog, and dampness-related agents. DISCUSSION This review, incorporating evidence reported since 2000, increases the strength of evidence linking many indoor factors to the exacerbation of asthma. Conclusions should be considered provisional until all available evidence is examined more thoroughly. CONCLUSION Multiple indoor exposures, especially dampness-related agents, merit increased attention to prevent exacerbation of asthma, possibly even in nonsensitized individuals. Additional research to establish causality and evaluate interventions is needed for these and other indoor exposures.
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Park J, Lee YK, Kim H, Hahn YS. Relationships of bronchodilator response with asthma control and fractional exhaled nitric oxide in children with atopic asthma. ALLERGY ASTHMA & RESPIRATORY DISEASE 2015. [DOI: 10.4168/aard.2015.3.1.40] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Joohyun Park
- Department of Pediatrics, Chungbuk National University College of Medicine, Cheongju, Korea
| | - Youn Kyung Lee
- Department of Pediatrics, Chungbuk National University College of Medicine, Cheongju, Korea
| | - Heon Kim
- Department of Preventive Medicine, Chungbuk National University College of Medicine, Cheongju, Korea
| | - Youn-Soo Hahn
- Department of Pediatrics, Chungbuk National University College of Medicine, Cheongju, Korea
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Reference values and factors associated with exhaled nitric oxide: U.S. youth and adults. Respir Med 2013; 107:1682-91. [PMID: 24041745 DOI: 10.1016/j.rmed.2013.07.006] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/16/2012] [Revised: 06/28/2013] [Accepted: 07/04/2013] [Indexed: 01/13/2023]
Abstract
BACKGROUND Normative values for fractional exhaled nitric oxide (FeNO) and the associated co-factors are important in understanding the role of FeNO as a biomarker in airway disease. The objective of this study is to establish reference FeNO values for youth and adult asymptomatic, lifetime nonsmokers in the United States, and to describe the factors affecting these levels. METHODS Cross-sectional analyses of the National Health and Nutrition Examination Survey from 2007 to 2010. The analytic sample consisted of 4718 youth and adults, ages 6-79 years, who were lifelong nonsmokers, and free of asthma, and other respiratory conditions and symptoms. Loge FeNO values were used as dependent variables to test associations of demographic and health related-covariates. Multivariable regression models were used to assess the independent effect and covariate-adjusted contribution of the factors. RESULTS The geometric mean FeNO level was 8.3, 12.1, and 16.2 ppb for males 6-11, 12-19, and 20-79 years, and 8.4, 10.9, and 12.6 ppb for females in the corresponding age groups. Overall, FeNO levels increased with increasing age (p < 0.001), and height (p < 0.001). In all age groups, FeNO levels were positively associated with eosinophil counts, and with testing in the morning. Among youths 6-11 and 12-19 years, non-Hispanics whites had lower FeNO values than non-Hispanic blacks and Hispanic youths. No race-ethnic difference in FeNO levels was evident for adults 20-79 years. Among adolescents and adults, FeNO levels were higher for males than for females, controlling for all other factors. CONCLUSIONS These reference values and associated attributes in youths and adults are useful in evaluating the role of FeNO in airway diseases.
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Johansson E, Reponen T, Vesper S, Levin L, Lockey J, Ryan P, Bernstein DI, Villareal M, Hershey GKK, Schaffer C, LeMasters G. Microbial content of household dust associated with exhaled NO in asthmatic children. ENVIRONMENT INTERNATIONAL 2013; 59:141-147. [PMID: 23807177 PMCID: PMC3759577 DOI: 10.1016/j.envint.2013.05.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2012] [Revised: 05/22/2013] [Accepted: 05/23/2013] [Indexed: 06/02/2023]
Abstract
Exhaled nitric oxide (eNO) is increasingly used as a non-invasive measure of airway inflammation. Despite this, little information exists regarding the potential effects of indoor microbial components on eNO. We determined the influence of microbial contaminants in house dust and other indoor environmental characteristics on eNO levels in seven-year-olds with and without a physician-diagnosis of asthma. The study included 158 children recruited from a birth cohort study, and 32 were physician-diagnosed as asthmatic. The relationship between eNO levels and exposures to home dust streptomycetes, endotoxin, and molds was investigated. Streptomycetes and endotoxin were analyzed both as loads and concentrations in separate models. Dog, cat, and dust mite allergens also were evaluated. In the multivariate exposure models, high streptomycetes loads and concentrations were significantly associated with a decrease in eNO levels in asthmatic (p<0.001) but not in healthy children. The presence of dog allergen, however, was associated with increased levels of eNO (p=0.001). Dust endotoxin was not significant. The relationship between eNO and indoor exposure to common outdoor molds was u-shaped. In non-asthmatic children, none of the exposure variables was significantly associated with eNO levels. To our knowledge, this is the first study demonstrating a significant association between microbial components in the indoor environment and eNO levels in asthmatic children. This study demonstrates the importance of simultaneously assessing multiple home exposures of asthmatic children to better understand opposing effects. Common components of the indoor Streptomyces community may beneficially influence airway inflammation.
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Affiliation(s)
- Elisabet Johansson
- Department of Environmental Health, University of Cincinnati, Box 670056, Cincinnati, OH 45267-0056, USA
| | - Tiina Reponen
- Department of Environmental Health, University of Cincinnati, Box 670056, Cincinnati, OH 45267-0056, USA
| | - Stephen Vesper
- US Environmental Protection Agency, 26 W. M. L. King Drive, Cincinnati, OH 45268, USA
| | - Linda Levin
- Department of Environmental Health, University of Cincinnati, Box 670056, Cincinnati, OH 45267-0056, USA
| | - James Lockey
- Department of Environmental Health, University of Cincinnati, Box 670056, Cincinnati, OH 45267-0056, USA
- Department of Internal Medicine, University of Cincinnati, OH, USA
| | - Patrick Ryan
- Department of Environmental Health, University of Cincinnati, Box 670056, Cincinnati, OH 45267-0056, USA
- Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, USA
| | - David I. Bernstein
- Department of Environmental Health, University of Cincinnati, Box 670056, Cincinnati, OH 45267-0056, USA
- Department of Internal Medicine, University of Cincinnati, OH, USA
| | - Manuel Villareal
- Department of Internal Medicine, University of Cincinnati, OH, USA
| | | | - Chris Schaffer
- Department of Environmental Health, University of Cincinnati, Box 670056, Cincinnati, OH 45267-0056, USA
| | - Grace LeMasters
- Department of Environmental Health, University of Cincinnati, Box 670056, Cincinnati, OH 45267-0056, USA
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Kalliola S, Pelkonen AS, Malmberg LP, Sarna S, Hämäläinen M, Mononen I, Mäkelä MJ. Maternal smoking affects lung function and airway inflammation in young children with multiple-trigger wheeze. J Allergy Clin Immunol 2013; 131:730-5. [PMID: 23380219 DOI: 10.1016/j.jaci.2013.01.005] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2012] [Revised: 01/11/2013] [Accepted: 01/11/2013] [Indexed: 11/17/2022]
Abstract
BACKGROUND Exposure to tobacco smoke is a well-known risk factor for childhood asthma and reduced lung function, but the effect on airway inflammation in preschool-aged children is unclear. OBJECTIVE To examine the effect of parental smoking on lung function and fractional concentration of exhaled nitric oxide (Feno) in relation to both parental reports and children's urine cotinine concentrations in preschool-aged children with multiple-trigger wheeze. METHODS A total of 105 3- to 7-year-old children with multiple-trigger wheeze and lung function abnormalities were recruited. Lung function was assessed by impulse oscillometry, and Feno measurements were performed. Exposure to tobacco smoke was determined by parental reports and measurement of children's urinary cotinine concentrations. RESULTS Forty-three percent of the children were exposed to environmental tobacco smoke according to parental reports. The Feno level was significantly higher in children with a smoking mother (n = 27) than in children with a nonsmoking mother (23.4 vs 12.5 ppb, P = .006). The Feno level expressed as z score and the cotinine level correlated significantly (P = .03). Respiratory resistance at 5 Hz was higher in children exposed to maternal smoking than in others (0.99 vs 0.88 kPas/L, P = .005). Urinary cotinine concentrations reflected well parental reports on their daily smoking and increased relative to the number of cigarettes smoked in the family (P < .01). Atopy was found in 75% of the children, but it was not associated with the Feno value (P = .65). CONCLUSION Maternal smoking was associated with increased Feno value and poorer lung function in steroid-naive preschool children with multiple-trigger wheeze. Larger controlled trials are needed to generalize the results.
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Affiliation(s)
- Satu Kalliola
- Department of Allergy, Helsinki University Central Hospital, Helsinki, Finland.
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Jartti T, Wendelin-Saarenhovi M, Heinonen I, Hartiala J, Vanto T. Childhood asthma management guided by repeated FeNO measurements: a meta-analysis. Paediatr Respir Rev 2012; 13:178-83. [PMID: 22726875 DOI: 10.1016/j.prrv.2011.11.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The fraction of exhaled nitric oxide (FeNO) has gained interest as a non-invasive tool to measure airway inflammation in asthma since it reflects allergic inflammation. Recent controlled clinical studies have, however, questioned its role in the management of asthma in children. To assess the clinical value of FeNO in paediatric asthma management, a meta-analysis was performed on the controlled studies of childhood asthma management guided by repeated FeNO measurements, and relevant publications on the confounders of FeNO were reviewed. The data suggests that utilising FeNO to tailor the dose of inhaled corticosteroids in children cannot be recommended for routine clinical practice since there is a danger of excessive inhaled corticosteroid doses in children without meaningful changes in clinical outcomes. Many disease and non-disease related factors (most importantly atopy, height/age and infection) affect FeNO levels which can easily confound the interpretation.
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Affiliation(s)
- Tuomas Jartti
- The Departments of Paediatrics, Turku University Hospital, Turku, Finland.
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Janahi I, Saadoon A, Tuffaha A, Panneerselvam B. Effects of age, gender, and environmental exposures on exhaled nitric oxide level in healthy 12 to 18 years Qatari children. Ann Thorac Med 2012; 7:98-103. [PMID: 22558015 PMCID: PMC3339211 DOI: 10.4103/1817-1737.94532] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2011] [Accepted: 09/29/2011] [Indexed: 11/06/2022] Open
Abstract
CONTEXT: Fractional exhaled nitric oxide (FENO) is a useful noninvasive diagnostic tool for asthma and some other pediatric respiratory diseases. Factors affecting FENO level are variable in different populations and studies. AIMS: To estimate the normal values of exhaled nitric oxide for Qataris 12 to 18 years of age. Other objectives were to measure the correlation of anthropometric and other potential factors with FENO levels. SETTINGS AND DESIGN: Community-based, cross-sectional study. METHODS: A total of 438 Qatari national school children from both genders were randomly recruited in cross-sectional study. Of them, 203 were non-atopic and hence included in the statistical analysis. Questionnaires including personal data, demographic data, and other factors that may affect FENO level were distributed. STATISTICAL ANALYSIS USED: Comparison of means done using t-test. We performed Spearman's rho test to measure correlations. Data analysis was done using PASW 18.0 Release 18.0.0, 2009. RESULTS: The geometric mean of FENO levels for all subjects was 14.1 ppb (upper level CI 95% - 36.3 ppb). FENO was significantly higher in males (R2 = −0.254, P<0.0001) and was negatively correlated with increasing age for the whole study population (P=0.036). This decline was interrupted by a significant upraise at the age of 15 years (P=0.0462) which seems to be driven by the males (P=0.0244). FENO levels were lower in subjects exposed to cats (P=0.019). We could not find significant correlation between FENO and other factors studied. CONCLUSIONS: Estimated FENO level with 95% CI in Qatari children, which is probably close to those in other Gulf countries, will be helpful clinically. The lower level of FENO with female gender, increasing age, and exposure to cats needs to be further studied to establish the association and to understand the underlying mechanisms.
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Affiliation(s)
- Ibrahim Janahi
- Department of Pediatrics, Hamad Medical Corporation, Qatar
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de la Riva-Velasco E, Krishnan S, Dozor AJ. Relationship between exhaled nitric oxide and exposure to low-level environmental tobacco smoke in children with asthma on inhaled corticosteroids. J Asthma 2012; 49:673-8. [PMID: 22799435 DOI: 10.3109/02770903.2012.701363] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVES The relationship between exhaled nitric oxide (FeNO) and asthma severity or control is inconsistent. Active smoking lowers FeNO, but the relationship between passive smoking and FeNO is less clear. Children may be exposed to low-level environmental tobacco smoke (ETS) or thirdhand smoke, even if parents avoid smoking in the presence of their children. Our hypothesis was that FeNO is lower in children with asthma exposed to low-level ETS when compared with those who are not exposed. METHODS Children with stable asthma, 8-18 years of age, on low- or medium-dose inhaled corticosteroids (ICS) were enrolled. Spirometry, Asthma Control Questionnaire (ACQ), FeNO, exhaled breath condensate pH (EBC pH), and EBC ammonia were compared between children with and without ETS exposure as determined by urinary cotinine. RESULTS Thirty-three subjects were enrolled, of which 10 (30%) had urinary cotinine levels ≥1 ng/ml. There were no significant differences between the two groups in age, sex, BMI percentile, atopy status, FEV(1), EBC pH, or EBC ammonia. Median ACQ was 0.29 (IQR: 0.22-0.57) for those with cotinine levels <1 ng/ml and 0.64 (IQR: 0.57-1.1) for those with cotinine levels of ≥1 ng/ml, p = .02. Median FeNO (ppb) was 23.9 (IQR: 15.2-34.5) for unexposed subjects and 9.6 (IQR: 5.1-15.8) for exposed subjects, p = .008. CONCLUSIONS Children with asthma on low to medium doses of ICS and recent low-level ETS exposure have lower FeNO levels when compared with non-ETS-exposed subjects. Exposure to low-level ETS or thirdhand smoke may be an important variable to consider when interpreting FeNO as a biomarker for airway inflammation.
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Affiliation(s)
- Elizabeth de la Riva-Velasco
- Division of Pediatric Pulmonology, Department of Pediatrics, Maria Fareri Children's Hospital at Westchester Medical Center and New York Medical College, Valhalla, NY 10595, USA.
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Environmental effects on fractional exhaled nitric oxide in allergic children. J Allergy (Cairo) 2011; 2012:916926. [PMID: 22162708 PMCID: PMC3228339 DOI: 10.1155/2012/916926] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2011] [Revised: 07/31/2011] [Accepted: 08/29/2011] [Indexed: 12/21/2022] Open
Abstract
Fractional exhaled nitric oxide (FeNO) is a non-invasive marker of airway inflammation in asthma and respiratory allergy. Environmental factors, especially indoor and outdoor air quality, may play an important role in triggering acute exacerbations of respiratory symptoms. The authors have reviewed the literature reporting effects of outdoor and indoor pollutants on FeNO in children. Although the findings are not consistent, urban and industrial pollution-mainly particles (PM(2.5) and PM(10)), nitrogen dioxide (NO(2)), and sulfur dioxide (SO(2))-as well as formaldehyde and electric baseboard heating have been shown to increase FeNO, whilst ozone (O(3)) tends to decrease it. Among children exposed to Environmental Tobacco Smoke (ETS) with a genetic polymorphisms in nitric oxide synthase genes (NOS), a higher nicotine exposure was associated with lower FeNO levels. Finally, although more studies are needed in order to better investigate the effect of gene and environment interactions which may affect the interpretation of FeNO values in the management of children with asthma, clinicians are recommended to consider environmental exposures when taking medical histories for asthma and respiratory allergy. Further research is also needed to assess the effects of remedial interventions aimed at reducing/abating environmental exposures in asthmatic/allergic patients.
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Sonnappa S, Bastardo CM, Stafler P, Bush A, Aurora P, Stocks J. Ethnic Differences in Fraction of Exhaled Nitric Oxide and Lung Function in Healthy Young Children. Chest 2011; 140:1325-1331. [DOI: 10.1378/chest.10-3280] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
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Grzelewski T, Majak P, Jerzyńska J, Cichalewski L, Krakowiak J, Stelmach W, Stelmach R, Janas A, Grzelewska A, Stelmach I. The association between fractional exhaled nitric oxide (FeNO) and cat dander in asthmatic children. Nitric Oxide 2011; 25:288-93. [PMID: 21621632 DOI: 10.1016/j.niox.2011.05.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2010] [Revised: 05/12/2011] [Accepted: 05/16/2011] [Indexed: 01/12/2023]
Abstract
BACKGROUND The aim of our study was to assess risk factors of increased FeNO in asthmatic children with no cat at home. METHODS It was a retrospective, cross-sectional study. We evaluated data from medical documentation of children with asthma: FeNO results, allergen sensitization, seasonal allergen exposure, FEV(1), allergic rhinitis (AR) diagnosis and cat presence at home. We assessed asthma severity using mean doses of inhaled glucocorticosteroids and a management approach based on control according to the newest guidelines of Global Initiative for Asthma (GINA) throughout the last three months before the measurement of FeNO and spirometry. RESULTS 316 patients (age 6-18) completed the study. Sensitization to cat dander was associated with the highest median value of FeNO concentration compared to other allergens in our patients (28,4ppb) and co-existing sensitization did not affect FeNO level. Median levels of FeNO increased linearly with patient's age. In asthmatics with AR, the levels of FeNO were increased significantly compared to asthmatics without AR (20.8 vs. 16.3, respectively). We showed that in patients without AR, sensitization to cat allergen was associated with more severe asthma in comparison to other perennial allergy (step 4 vs. other steps according to GINA treatment steps). The above relation was not observed in patients with AR. We did not observe correlation between allergy profile and FEV(1) among patients in neither subgroup nor in general population. CONCLUSIONS We revealed that sensitization to cat dander was associated with the highest increase of FeNO concentration compared to other allergens in patients not having any cat at home ever. We also observed that in patients without allergic rhinitis, sensitization to cat allergen, compared to other perennial allergy, was associated with more severe asthma.
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Affiliation(s)
- Tomasz Grzelewski
- Department of Pediatrics and Allergy, Medical University of Lodz, N. Copernicus Hospital, Lodz, Poland
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Spanier AJ, Kahn RS, Hornung R, Lierl M, Lanphear BP. Associations of Fraction of Exhaled Nitric Oxide with Beta Agonist Use in Children with Asthma. PEDIATRIC ALLERGY, IMMUNOLOGY, AND PULMONOLOGY 2011; 24:45-50. [PMID: 22276224 PMCID: PMC3255503 DOI: 10.1089/ped.2010.0047] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2010] [Accepted: 02/10/2011] [Indexed: 12/16/2022]
Abstract
The fraction of exhaled nitric oxide (FeNO), a measure of airway inflammation, is a potential noninvasive tool to guide asthma management in children. It remains unclear, however, if FeNO adds any information beyond clinical assessment of asthma control. We evaluated the associations of FeNO level with short acting beta agonist use and compared it with other clinical asthma assessments. We examined a prospective cohort study of 225 tobacco-smoke-exposed children aged 6-12 years with doctor-diagnosed asthma, including measures of FeNO, reported days of short acting beta agonist use, and unscheduled asthma visits. FeNO was analyzed in relation to current and future (3 months later) short acting beta agonist use. Mean FeNO at baseline, 6, and 12 months was 15.5, 15.7, and 16.8 ppb. In multivariable analyses, higher FeNO level was associated with increased short acting beta agonist use but only among children who were not on inhaled corticosteroids. Among those not on an inhaled steroid, there was a 12% increase in current and 15% increase in future days of short acting beta agonist use for every 10 ppb increase in FeNO level. FeNO levels remained associated with current short acting beta agonist use even after adjusting for unscheduled asthma visits. FeNO levels remained associated with future short acting beta agonist use even after adjusting for current short acting beta agonist use or unscheduled asthma visits. We conclude that FeNO levels are associated with short acting beta agonist use but only among children who are not on an inhaled corticosteroid.
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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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Kalkbrenner AE, Hornung RW, Bernert JT, Hammond SK, Braun JM, Lanphear BP. Determinants of serum cotinine and hair cotinine as biomarkers of childhood secondhand smoke exposure. JOURNAL OF EXPOSURE SCIENCE & ENVIRONMENTAL EPIDEMIOLOGY 2010; 20:615-624. [PMID: 20237497 PMCID: PMC2972673 DOI: 10.1038/jes.2010.7] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2009] [Accepted: 02/02/2010] [Indexed: 05/27/2023]
Abstract
Understanding the determinants of childhood secondhand smoke (SHS) exposure is important in measuring and preventing exposure to this widespread environmental contaminant. We evaluated the ability of a broad set of factors to explain variability in serum cotinine, reflecting recent exposure, and hair cotinine, reflecting longer-term exposure. We included repeated measures from 223 elementary-school-age asthmatic children residing with a smoker. We used a manual model-building approach and likelihood ratio tests to select a model predicting each biomarker, and also compared the predictive ability of determinants using Akaike Information Criteria. Potential determinants included a comprehensive parent questionnaire, household nicotine, home ventilation characteristics, exposure in vehicles and others' homes, child demographics, and family social class. Variables in each of these categories remained in the final model for both serum (R(2) of 0.61) and hair cotinine (R(2) of 0.45). A comprehensive set of factors was required to best predict cotinine. Studies should use biomarkers for the best quantitative assessment of SHS exposure. Hair cotinine may be a problematic measure because it was highly influenced by racial differences that were unexplained by SHS exposure. When biospecimen collection is not possible, a household nicotine measurement is warranted. If only questionnaires are available, multiple questions are required to best characterize exposure, such as number of cigarettes, hours spent in a room with concurrent smoking, maternal smoking, and approximate home size.
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Affiliation(s)
- Amy E Kalkbrenner
- Department of Epidemiology, University of North Carolina, Chapel Hill, North Carolina, USA.
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Effects of the indoor environment on the fraction of exhaled nitric oxide in school-aged children. Can Respir J 2010; 16:e18-23. [PMID: 19557209 DOI: 10.1155/2009/954382] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND The fractional concentration of exhaled nitric oxide (FeNO) appears to be a good marker for airway inflammation in children with asthma. OBJECTIVE To evaluate the effect of environmental exposures on exhaled nitric oxide in a community sample of children. METHODS The relationship among exhaled nitric oxide, underlying disease and home environmental exposures was examined using questionnaire data and measurement of exhaled nitric oxide in a cross-sectional study of 1135 children that included healthy children, and children with allergies and/or asthma who were attending grades 4 through 6 in Windsor, Ontario. RESULTS Among healthy children, there was a positive association between FeNO and occupancy (P<0.02). Compared with forced air and hot water radiant heat, electric baseboard heating was associated with a significant increase of FeNO in healthy children (P=0.007) and children with allergies (P=0.043). FeNO was not associated with environmental tobacco smoke exposure or reported surface mold. The presence of pet dog(s), but not cats, was associated with a significantly lower FeNO in healthy children (P<0.001) and in children with reported allergies (P<0.001). CONCLUSIONS The type of heating system, but not previously reported environmental tobacco smoke or mold exposure appears to affect exhaled nitric oxide in children. Exposure to different types of pets may have disparate effects on airway inflammation.
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White blood cell DNA adducts in a cohort of asthmatic children exposed to environmental tobacco smoke. Int Arch Occup Environ Health 2010; 84:19-27. [PMID: 20336464 PMCID: PMC2922034 DOI: 10.1007/s00420-010-0529-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2009] [Accepted: 03/09/2010] [Indexed: 11/06/2022]
Abstract
Purpose Exposure to environmental tobacco smoke (ETS) leads to molecular damage in the form of DNA adducts. While lung cancer risk is higher among African Americans compared to White Americans, a few studies have tested for racial differences in DNA adducts among children exposed to ETS. The purpose of this study was to test whether African American children have higher DNA adducts levels compared to White children adjusted for ETS exposure. Methods Data and biologic specimens were drawn from an existing cohort of 212 asthmatic children. These subjects participated in a 12-month ETS-reduction trial that employed HEPA air cleaners with active filter cartridges and sham filter cartridges. White blood cell (WBC) DNA was analyzed for DNA adducts using 32P-postlabeling. We assessed ETS exposure using a validated air nicotine dosimeter. We determined the independent relationship between African American race and DNA adduct levels adjusted for ETS exposure and air cleaner use. Results The mean age of the subjects was 8.4 years; 55% were African American. There was no difference in DNA adduct levels between African American and White children (11.8 vs. 11.2 adducts per 109 nucleotides, p = 0.86), despite slightly higher levels of air nicotine exposure (3.4 vs. 2.2 μg/m3, p = 0.14). African American children used their air cleaners less often than White children. We found that the best predictor of DNA adduct levels was the duration of air cleaner use (r = −0.133, p = 0.056). This association was independent of cartridge type. Conclusions We did not see differences in adduct levels by race even after accounting for the level of ETS exposure. However, there was a marginal inverse association between air cleaner use and adducts. Additional research is required to understand this phenomenon.
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Liu HC, Hsu JY, Cheng YW, Chou MC. Exhaled nitric oxide in a Taiwanese population: age and lung function as predicting factors. J Formos Med Assoc 2010; 108:772-7. [PMID: 19864197 DOI: 10.1016/s0929-6646(09)60404-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND/PURPOSE The fractional concentration of exhaled nitric oxide (FE(NO)) has been reported to be elevated in asthma and many other lung diseases. The present study investigated reference values and determinants of FE(NO) in a Taiwanese non-smoking, healthy adult population. METHODS We used a chemiluminescence analyzer according to American Thoracic Society/European Respiratory Society recommendations to measure FE(NO) values in 356 adults who received a health check-up and a detailed respiratory questionnaire at Taichung Veterans General Hospital, Taiwan. Among the volunteers, 249 fulfilled our definition of healthy adults: no history of smoking or physician-diagnosed asthma; no recent upper airway infection; no chronic respiratory symptoms; and no allergic rhinitis and urticaria. RESULTS Among the 249 non-smoking and non-asthmatic adults, the mean (5th to 95th percentile reference range) FE(NO) was 27.9 (12.5-58.0) parts per billion. In multivariate regression analyses, age and lung function (forced vital capacity or forced expiratory volume in 1 second) were associated positively with FE(NO) values. Sex, height, weight, and ambient NO values were not associated significantly with FE(NO) values. CONCLUSION Age and lung function were predictors of FE(NO) in this population, and these factors should be considered for clinical applications of FE(NO) measurements.
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Affiliation(s)
- Hsu-Chung Liu
- Division of Chest Medicine, Department of Internal Medicine, Taichung Veterans General Hospital, Taichung, Taiwan
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Spanier AJ, Kahn RS, Hornung RW, Wang N, Sun G, Lierl MB, Lanphear BP. Environmental exposures, nitric oxide synthase genes, and exhaled nitric oxide in asthmatic children. Pediatr Pulmonol 2009; 44:812-9. [PMID: 19603529 PMCID: PMC2857409 DOI: 10.1002/ppul.21071] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Exhaled nitric oxide (FeNO), a measure of airway inflammation, is being explored as a tool to guide asthma management in children. Investigators have identified associations of genetic polymorphisms in nitric oxide synthase genes (NOS1 and NOS3) with FeNO levels; however, none have explored whether these polymorphisms modify the relationship of environmental exposures with FeNO. The objective of this project was to evaluate the association of NOS polymorphisms and environmental exposures with FeNO levels among children with asthma. We conducted a 12-month prospective cohort study of 225 tobacco-smoke exposed children (6-12 years) with doctor-diagnosed asthma. We assessed environmental exposures (tobacco, indoor allergens, & airborne particulates), polymorphisms in NOS1 (an intronic AAT tandem repeat) and NOS3 (G894T), and FeNO levels. There was no association of NOS1 or NOS3 polymorphisms with FeNO levels. There were no significant interactions of environmental exposures and the NOS1 polymorphism with FeNO levels. In contrast, there was an interaction of the NOS3 polymorphism and airborne nicotine concentration with FeNO levels (P = 0.01). Among GG genotype individuals, nicotine exposure did not affect FeNO levels; however, among individuals with at least one T allele, higher nicotine exposure was associated with lower FeNO levels (approximately 5 ppb decrease from the lowest to the highest quartile). We conclude that genetic differences may explain some of the conflicting results in studies of the effects of tobacco smoke exposure on FeNO levels and may make FeNO interpretation difficult for a subset of children with asthma.
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Affiliation(s)
- Adam J Spanier
- Cincinnati Children's Environmental Health Center, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA.
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Biological matrices for the evaluation of exposure to environmental tobacco smoke during prenatal life and childhood. Anal Bioanal Chem 2009; 396:379-99. [DOI: 10.1007/s00216-009-2831-8] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2009] [Revised: 04/26/2009] [Accepted: 04/30/2009] [Indexed: 10/20/2022]
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The value of FeNO measurement in asthma management: the motion for Yes, it's NO--or, the wrong end of the Stick! Paediatr Respir Rev 2008; 9:127-31. [PMID: 18513673 DOI: 10.1016/j.prrv.2007.12.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The utility of measurements of exhaled nitric oxide (FeNO) will likely depend on context, being most helpful in moderate and severe asthma, rather than mild asthmatics and community based studies. Atopy on its own is a cause of elevation in FeNO. Adult and paediatric studies have clearly established that measurement of some aspect of airway inflammation is part of state of the art management of asthma, but it is as yet unclear which of several techniques is most useful. The relationship between FeNO and sputum eosinophils is relatively loose, but this does not preclude it being a useful test in clinical practice. In fact, there are only poor correlations between sputum, proximal mucosal, and distal eosinophils, and the importance of these different compartments is unclear. A low FeNO in the setting of supposedly poorly controlled asthma should cast doubt on the diagnosis. We certainly cannot treat an isolated elevation in FeNO, which may be due to a simple viral cold, or constitutional. If FeNO is elevated, particularly if asthma is uncontrolled, it suggests an imbalance between anti-inflammatory therapy and pro-inflammatory environmental influences. Inadequate anti-inflammatory therapy may be due to the prescribed dose being too low; the drug delivery device not being used correctly; or the medication not being taken. Adverse pro-inflammatory environmental influences driving up FeNO include IgE and non-IgE mediated allergen sensitivity in the home, and even in the child's school. Novel technology allows home monitoring of FeNO, but the role of these devices is less clear. Although more data is needed properly to define the role of FeNO measurements in clinical practice, there is sufficient data already published to conclude that 'inflammometry' is an important part of asthma management at the more severe end of the spectrum, and that FeNO measurements are probably the most useful at the moment.
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Spanier AJ, Hornung RW, Kahn RS, Lierl MB, Lanphear BP. Seasonal variation and environmental predictors of exhaled nitric oxide in children with asthma. Pediatr Pulmonol 2008; 43:576-83. [PMID: 18429012 PMCID: PMC3483596 DOI: 10.1002/ppul.20816] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The fraction of exhaled nitric oxide (FeNO), a measure of airway inflammation, shows promise as a noninvasive tool to guide asthma management, but there is a paucity of longitudinal data about seasonal variation and environmental predictors of FeNO in children. The objective of this project was to evaluate how environmental factors affect FeNO concentrations over a 12-month study period among children with doctor diagnosed asthma. We conducted a prospective cohort study of 225 tobacco-smoke exposed children age 6-12 years with doctor-diagnosed asthma including measures of FeNO, medication use, settled indoor allergens (dust mite, cat, dog, and cockroach), and tobacco smoke exposure. Baseline geometric mean FeNO was 12.4 ppb (range 1.9-60.9 ppb). In multivariable analyses, higher baseline FeNO levels, atopy, and fall season were associated with increased FeNO levels, measured 6 and 12 months after study initiation, whereas inhaled steroid use, summer season, and increasing nicotine exposure were associated with lower FeNO levels. In secondary analyses of allergen sensitization, only sensitization to dust mite and cat were associated with increased FeNO levels. Our data demonstrate that FeNO levels over a year long period reflected baseline FeNO levels, allergen sensitization, season, and inhaled steroid use in children with asthma. These results indicate that FeNO levels are responsive to common environmental triggers as well as therapy for asthma in children. Clinicians and researchers may need to consider an individual's baseline FeNO levels to manage children with asthma.
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Affiliation(s)
- Adam J Spanier
- Cincinnati Children's Environmental Health Center, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229-3039, USA.
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Martins P, Caires I, Pinto JR, da Mata PL, Torres S, Valente J, Borrego C, Neuparth N. Medição do óxido nítrico no ar exalado: Utilização na avaliação de crianças com história de sibilância. REVISTA PORTUGUESA DE PNEUMOLOGIA 2008. [DOI: 10.1016/s0873-2159(15)30230-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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Fleming L, Wilson N, Bush A. No the evidence: what have measurements of exhaled nitric oxide got to offer? J Pediatr 2006; 149:156-8. [PMID: 16887425 DOI: 10.1016/j.jpeds.2006.05.035] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2006] [Accepted: 05/18/2006] [Indexed: 10/24/2022]
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