Impact of allergic rhinitis on asthma: effects on bronchial hyperreactivity.
BACKGROUND
Remarkable relationship exists between upper and lower airways. Bronchial hyperreactivity (BHR) is a paramount feature of asthma and may be considered a strong risk factor for the onset of asthma in patients with allergic rhinitis.


OBJECTIVE
This study is aimed at evaluating the presence of BHR in a large group of patients with moderate-severe persistent allergic rhinitis alone, and at investigating possible risk factors related to severe BHR.


METHODS
Three hundred and forty-two patients with moderate-severe persistent allergic rhinitis were prospectively and consecutively evaluated. Clinical examination, skin prick test, spirometry and bronchial methacholine (MCH) test were performed in all patients.


RESULTS
Twenty-two (6.4%) patients had severe BHR, 74 (21.6%) patients had mild BHR and 192 (56.2%) had borderline BHR; 54 (15.8%) patients had a negative MCH test. The logistic regression analysis evidenced that trees and house dust mites sensitization (ORAdj: 8.1), rhinitis duration > 5 years (ORAdj: 5.4) and FEV1 < or = 86% of predicted (ORAdj: 4.0) were significantly associated with severe BHR. The discriminative ability of this model is appreciably satisfactory, being the AUC = 0.90.


CONCLUSIONS
This study highlights the close link between upper and lower airways and the role of some risk factors, such as tree and mite sensitization, > 5-year duration, and < or = 86% FEV1 values, as risk factors for severe BHR in patients with moderate-severe persistent allergic rhinitis alone. Therefore, BHR is frequently present in patients with chronic rhinitis and should be suspected in the presence of defined risk factors.
Cirillo
I
I
Navy Medical Service, La Spezia, Italy.
Pistorio
A
A
Tosca
M
M
Ciprandi
G
G
D000328:Adult; D001249:Asthma / Q000150:complications* / Q000503:physiopathology*; D016535:Bronchial Hyperreactivity / Q000150:complications* / Q000503:physiopathology*; D001985:Bronchial Provocation Tests; D005260:Female; D006801:Humans; D008297:Male; D012220:Rhinitis / Q000150:complications*; D012307:Risk Factors; D012882:Skin Tests