Original Articles: Asthma Lower Airway DiseasesExhaled nitric oxide as a predictor of exacerbation in children with moderate-to-severe asthma: a prospective, 5-month study
Section snippets
INTRODUCTION
Although inhaled corticosteroids (ICSs) are the recommended first-line treatment for asthma in children,1, 2, 3 long-term use can lead to systemic effects,4, 5 and, therefore, the lowest dose needed to maintain good asthma control should be used. Because of the great variability of the dose required both between children and within individual children, safe methods to guide titration are highly desirable. Once a patient has achieved control over a period, the health care provider can carefully
Study Population
We examined all 104 children aged 7 to 14 years who met the criteria for moderate-to-severe asthma1 (based on current history, stability of disease in the previous year, rates of exacerbation, medication needs, and pulmonary function) and, as of the start of the study protocol in October 2004, had been receiving care from us at the outpatient clinic of Hospital Infantil Darcy Vargas, Sao Paulo, Brazil, for at least 12 months. From this group, we excluded 72 children: 34 who had not been
RESULTS
Of the 32 children who began the study, 27 completed all 7 follow-up visits after the initiation of tapering; the other 5 completed all but the last follow-up visit. All are included in the analysis. Study participants averaged 10.3 years of age, and 66% were male (Table 1).
At the beginning of tapering, the average FEV1 was 90.0% of the predicted value and the average ENO level was 38 ppb. As expected, the clinical indicators were worse for the 14 children with severe asthma compared with the
DISCUSSION
Our results showed that ENO measurements were not a predictor of future exacerbation in children with atopic, moderate-to-severe asthma undergoing a period of steroid tapering.
Prior studies addressing the utility of ENO as a predictor of asthma exacerbations have shown conflicting results. Several studies failed to prove that ENO was a good predictor of loss of control or future exacerbation in adult9, 22, 37 patients while tapering the ICS dose. More recently, Menzies et al22 evaluated the
ACKNOWLEDGMENTS
We acknowledge the contribution of the American Thoracic Society’s Methods in Epidemiologic, Clinical and Operations Research course in the development of this article.
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2014, ChestCitation Excerpt :Some pediatric patients may have difficulty verbalizing respiratory symptoms, whereas others may have difficulty perceiving a change in their respiratory status.51 Objective parameters to predict loss of asthma control, including traditional spirometry and exhaled nitric oxide levels, do not appear to accurately reflect a decline in asthma control.52–54 In a recent study, Shi et al50 demonstrated that children with controlled asthma who have increased peripheral airway IOS indexes are at risk for losing asthma control, which suggests that monitoring small airway function by IOS can be useful in identifying patients who are at risk for losing asthma control and in assisting with clinical decisions and treatment plans.
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2014, Allergologia et ImmunopathologiaCitation Excerpt :Although one might expect that frequent assessments of eNO would increase the usefulness of this index as a factor predictive of exacerbation, Dutch researchers have observed only a statistically insignificant trend towards reduction in the number of exacerbations, while monitoring the treatment by daily home-based monitoring of eNO levels.25 In addition, in the recent study by Cabral, eNO assessed every two weeks was not a clinically useful predictive factor of future exacerbations.26 The final analysis of clinical outcomes in patients who completed the 12-week study did not show significant worsening of the parameters.
Guideline-recommended fractional exhaled nitric oxide is a poor predictor of health-care use among inner-city children and adolescents receiving usual asthma care
2013, ChestCitation Excerpt :In addition, these studies do not shed light on the potential application of Feno testing at regular intervals that might approximate real-time use of testing in clinical settings. While studies in adults might be slightly more encouraging,10,24,30 studies in school-age children have not strongly supported the use of Feno data in asthma management.1,20,24,31–33 A large clinical trial of inner-city adolescents with asthma found that adding Feno level as an indicator of asthma control resulted in higher doses of ICS without clinical benefit.1
Peripheral airway impairment measured by oscillometry predicts loss of asthma control in children
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Disclosures: Authors have nothing to disclose.
Funding Sources: This study was supported by the following Brazilian scientific agencies: Fundação de Amparo à Pesquisa do Estado de São Paulo and Conselho Nacional de Desenvolvimento Científico e Tecnológico.
Previous Presentation: Presented in part at the International Meeting of the American Thoracic Society; San Francisco, California; May 22, 2007.