Exhaled nitric oxide may predict bronchial hyperreactivity in patients with allergic rhinitis.
BACKGROUND
Nowadays it is possible to assess airway inflammation by measuring the fractional concentration of exhaled nitric oxide (FeNO) during an office visit and there is international consensus on the testing methodology. The aim of this study was to evaluate whether FeNO measurement may be a predictor of bronchial hyperreactivity (BHR) in patients with allergic rhinitis (AR).


METHODS
Two hundred eleven patients (196 males, median age 28.5 years) suffering from persistent AR were evaluated. Values for bronchial function (FVC, FEV(1), and FEF(25-75)), bronchial provocation tests (methacholine), exhaled nitric oxide (FeNO), a visual analogue scale for nasal and bronchial symptoms, and sensitization were assessed.


RESULTS
A strong and inverse correlation between FeNO levels and BHR severity was found (r = -0.58). FeNO was a predictive factor for BHR, and 37 ppb was found to be the best cutoff (area under the curve 0.90) to define the presence of BHR in patients with AR.


CONCLUSIONS
This study highlights the relevance of FeNO as a possible predictive marker for BHR in AR patients and underlines the close link between upper and lower airways. Thus, FeNO measurement could be a useful screening tool in identifying subjects with rhinitis at risk of developing asthma.
Navy Medical Service, La Spezia, Italy.
Ignazio
I
Cirillo
Fabio Luigi Massimo
FL
Ricciardolo
Gianmarco
G
Medusei
Alessio
A
Signori
Giorgio
G
Ciprandi
D000328:Adult; D015415:Biomarkers / Q000378:metabolism*; D001944:Breath Tests / Q000379:methods*; D016535:Bronchial Hyperreactivity / Q000150:complications / Q000175:diagnosis*; D001985:Bronchial Provocation Tests; D018450:Disease Progression; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D008297:Male; D009569:Nitric Oxide / Q000378:metabolism*; D011237:Predictive Value of Tests; D011379:Prognosis; D012221:Rhinitis, Allergic, Perennial / Q000150:complications / Q000175:diagnosis*; D012306:Risk
D015415:Biomarkers; D009569:Nitric Oxide