Allergic rhinitis and onset of bronchial hyperresponsiveness -: A population-based study

Rationale Patients with allergic rhinitis have more frequent bronchial hyperresponsiveness (BHR) in cross-sectional studies. Objectives: To estimate the changes in BHR in nonasthmatic subjects with and without allergic rhinitis during a 9-year period. Methods: BHR onset was studied in 3,719 subjects without BHR at baseline, who participated in the follow-up of the European Community Respiratory Health Survey. Measurements and Main Results: BHR was defined as a >= 20% decrease in FEV1 for a maximum dose of 1 mg of methacholine. Allergic rhinitis was defined as having a history of nasal allergy and positive specific IgE (>= 0.35 IU/ml) to pollen, cat, mites, or Cladosporium. The cumulative incidence of BHR was 9.7% in subjects with allergic rhinitis and 7.0% in subjects with atopy but no rhinitis, compared with 5.5% in subjects without allergic rhinitis and atopy (respective odds ratios [OR] and their 95% confidence intervals [95% CI] for BHR onset, 2.44 [1.73-3.45]; and 1.35 [0.86-2.11], after adjustment for potential confounders including sex, smoking, body mass index and FEV1). Subjects with rhinitis sensitized exclusively to cat or to mites were particularly at increased risk of developing BHR (ORs [95% CI], 7.90 [3.48-17.93] and 2.84 [1.36-5.93], respectively). Conversely, in subjects with BHR at baseline (n = 372), 35.3% of those with allergic rhinitis, compared with 51.8% of those without rhinitis had no more BHR at follow-up (OR [95% CI], 0.51 [0.33-0.781). BHR remission was more frequent in patients with rhinitis treated by nasal steroids than in those not treated (OR [95% CI], 0.33 [0.14-0.75]). Conclusions: Allergic rhinitis was associated with increased onset of BHR, and less chance for remission except in those treated for rhinitis.