Association between asthma and rhinitis according to atopic sensitization in a population-based study.
BACKGROUND
Although asthma and rhinitis often occur together, the reason for this common comorbidity is still a matter of debate.


OBJECTIVE
We sought to assess whether the coexistence of asthma and rhinitis could be explained by common risk factors.


METHODS
International cross-sectional study of representative samples of young adults, who completed a detailed questionnaire and underwent lung function tests, bronchoprovocation challenge, IgE measurements, and skin prick tests.


RESULTS
In all countries, asthma and bronchial hyperreactivity were more frequent in subjects with rhinitis than in those without (odds ratio [OR], 6.63; 95% CI, 5.44-8.08; and OR, 3.02 95% CI, 2.66-3.43, respectively). Seventy-four percent to 81% of subjects with asthma reported rhinitis, depending on sensitization to specific allergens. Conversely, the risk of asthma increased from 2.0% in subjects without rhinitis to 6.7% in subjects with rhinitis only when exposed to pollen, 11.9% in subjects with rhinitis when exposed to animals, and 18.8% in subjects with rhinitis either when exposed to pollen or to animals. The association between rhinitis and asthma remained significant after adjustment for total IgE, parental history of asthma, and allergen sensitization (OR, 3.41; 95% CI, 2.75-4.2 suggesting that the coexistence of asthma and rhinitis is not solely due to atopic predisposition to these 2 diseases.


CONCLUSIONS
Although there were some variations in the association between asthma and rhinitis according to sensitization to individual allergens, the strong association between asthma and rhinitis was not fully explained by shared risk factors, including atopy. Our findings are consistent with the hypothesis that rhinitis might increase the risk of asthma.
Leynaert
Bénédicte
B
Inserm Unité 408, Paris, France.
Neukirch
Catherine
C
Kony
Sabine
S
Guénégou
Armelle
A
Bousquet
Jean
J
Aubier
Michel
M
Neukirch
Françoise
F
D000328:Adult; D000485:Allergens / Q000276:immunology; D001249:Asthma / Q000150:complications* / Q000453:epidemiology; D016535:Bronchial Hyperreactivity / Q000150:complications* / Q000453:epidemiology; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood; D008297:Male; D011058:Pollen; D015995:Prevalence; D012129:Respiratory Function Tests; D012221:Rhinitis, Allergic, Perennial / Q000150:complications* / Q000453:epidemiology; D012307:Risk Factors; D012882:Skin Tests; D011795:Surveys and Questionnaires
D000485:Allergens; D007073:Immunoglobulin E