Relationships of methacholine and adenosine 5'-monophosphate (AMP) responsiveness to the postbronchodilator FEV1/FVC ratio in children with asthma.
J Asthma
; 48(4): 345-50, 2011 May.
Article
em En
| MEDLINE
| ID: mdl-21504349
ABSTRACT
BACKGROUND:
Airway remodeling has been assumed to cause bronchial hyperresponsiveness (BHR). A low postbronchodilator FEV1/FVC ratio has been suggested to be a functional surrogate marker of airway remodeling in asthma. BHR is commonly assessed by bronchial challenges using direct or indirect stimuli.OBJECTIVE:
The aim of this study was to compare BHR to methacholine and adenosine 5'-monophosphate (AMP) with regard to their relationship with a marker of airway remodeling in children with asthma.METHODS:
Methacholine and AMP challenge tests were performed in 129 children with asthma, aged 12 years, and a provocative concentration causing a 20% fall in FEV1 (PC20) was calculated for each challenge. All subjects also underwent pre- and postbronchodilator spirometry. A postbronchodilator FEV1/FVC ratio below the lower limits of normal was used as a marker of airway remodeling.RESULTS:
A low postbronchodilator FEV1/FVC ratio was found in 17 subjects (13.2%). These subjects had a significantly lower methacholine PC20 (geometric mean 0.63 mg/mL, range of 1 SD 0.17-2.29) than those (n = 112) with a normal postbronchodilator FEV1/FVC ratio (2.42 mg/mL, 0.57-10.32, p = .000), whereas AMP PC20 was similar between the two groups (22.1 mg/mL, 3.9-125.9 vs. 27.7 mg/mL, 4.2-183.5, p = .231). In the whole group of subjects, methacholine PC20, but not AMP PC20, correlated significantly with the postbronchodilator FEV1/FVC ratio (r = 0.340, p = .000, and r = 0.056, p = .526, respectively).CONCLUSIONS:
Our results provide evidence, though indirect, that BHR to methacholine is related to airway remodeling in children with asthma and suggest that BHR to methacholine may be a better marker of airway remodeling than BHR to AMP.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Asma
/
Broncodilatadores
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Monofosfato de Adenosina
/
Capacidade Vital
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Volume Expiratório Forçado
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Broncoconstritores
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Cloreto de Metacolina
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Hiper-Reatividade Brônquica
Limite:
Child
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Female
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Humans
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Male
Idioma:
En
Ano de publicação:
2011
Tipo de documento:
Article