Airway hyperresponsiveness: a comparative study of methacholine and exercise challenges in seasonal allergic rhinitis with or without asthma.
J Asthma
; 46(5): 486-91, 2009 Jun.
Article
en En
| MEDLINE
| ID: mdl-19544170
ABSTRACT
BACKGROUND:
Asymptomatic airway hyperreactivity in allergic rhinitis is a risk factor for later development of asthma. Although non-specific bronchial hyperresponsiveness (BHR) has been measured by several stimuli, the most appropriate measurement technique still remains unclear.OBJECTIVE:
To investigate whether an exercise challenge can be used to predict BHR in seasonal allergic rhinitis patients with or without asthma and to compare this bronchial reactivity with a methacholine challenge technique.METHODS:
Forty-six consecutive patients with seasonal allergic rhinitis only (n = 31) and with both seasonal allergic rhinitis and asthma (n = 15) were included in the study during the pollination period. Subjects underwent first methacholine (mch) and then exercise challenge testing (ECT). There was a 1-week interval between the tests. ECT was performed on a bicycle ergometer. Positive result was defined as a 15% decrease in forced expiratory volume in 1 second (FEV(1)) post-exercise. A patient's bronchial reactivity to methacholine was considered as hyperresponsive if PC(20) was less than 8 mg/mL.RESULTS:
Mch PC(20) values were significantly lower in patients with both rhinitis and asthma (p < 0.062). Among the 46 patients, mch PC(20) values were significantly different between patients who had positive and negative exercise challenge tests (p = 0.007). All patients with rhinitis alone had a negative ECT and 10 had a positive mch challenge. Change in FEV(1) values after ECT was significantly higher in patients with both rhinitis and asthma compared to those with rhinitis alone (p = 0.009). There was a significant relation between positivity of mch and exercise challenges (p = 0.025). ECT positivity was found to be a significant confounding factor in the diagnosis of asthma (p = 0.001). Specificity and sensitivity values were 100% and 24% for ECT and 68% and 100% for mch, respectively.CONCLUSION:
Exercise challenge presents poor diagnostic value for detecting bronchial responsiveness in individuals with allergic rhinitis alone during the pollen season.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Asma
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Rinitis Alérgica Estacional
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Cloruro de Metacolina
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Hiperreactividad Bronquial
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Prueba de Esfuerzo
Tipo de estudio:
Diagnostic_studies
/
Etiology_studies
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Prognostic_studies
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Risk_factors_studies
Límite:
Adult
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Female
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Humans
/
Male
Idioma:
En
Revista:
J Asthma
Año:
2009
Tipo del documento:
Article
País de afiliación:
Turquía