Objective: Observe the changes of small airway function in patients with rhinitis but without asthma and/or lower airway symptoms.
Method: Between June 2008 and December 2012, we recruited 903 subjects, including 377 with allergic rhinitis (AR), 262 with non-allergic rhinitis (NAR) and 264 healthy subjects. All subjects underwent meticulous history taking, nasal examination, allergen skin prick test, blood routine test, serum total immunoglobin E assay, pulmonary ventilation function test and bronchial challenge test.
Result: The indices of FEV1/FVC%, MEF25pred% and MMEFpred% were lower in AR group than in the control group (P < 0.05). The indices of FEV1/FVC, MMEFpred%, MEF25pred% and MEF50pred% were also lower in NAR group than in the control group (P < 0.05). According to the FVCpred% and FEV1pred%, there were no differences between rhinitis group and the control group (P > 0.05). The positive rate of airway hyperresponsiveness(AHR) in AR group and in NAR group was 12.2%, 6.1% respectively. Indices of small airway function were all lower in the AHR group than NAHR group in rhinitis.
Conclusion: Compared with healthy controls, small airway function in patients with rhinitis has apparent changes, part of rhinitis patients has AHR, and is associated with small airway function changes.