Co-existence of asthma and allergic rhinitis: a 23-year follow-up study of college students.

The purpose of this study is to examine the co-existence of asthma and allergic rhinitis among former college students who were diagnosed with these diseases either before or after their freshman year. A total of 738 former Brown University students (69% males and 31% females) who were evaluated and underwent skin testing during their freshman year completed a 23-year follow-up questionnaire inquiring of their history of allergies and asthma. The mean age of the participants at the time of the follow-up study was 40 years. In this group, the cumulative incidence of asthma was 11.3% (84/738), hay fever was 41.5% (306/738), and nonseasonal allergic rhinitis was 14.0% (103/738). The cumulative incidence of allergic rhinitis (hay fever) and/or nonseasonal allergic rhinitis (was 45.8% (338/738). Among the 84 individuals with a cumulative incidence of asthma, 63 (75.0%) had a history of hay fever, 27 (32.1%) had a history of nonseasonal allergic rhinitis, and 72 (85.7%) had a history of allergic rhinitis. Among the 306 participants with a cumulative incidence of hay fever, 63 (20.6%) had a history of asthma. Twenty-seven (26.2%) of the 103 individuals with a history of nonseasonal allergic rhinitis had a cumulative incidence of asthma. Among the 338 individuals with a cumulative incidence of allergic rhinitis 72 (21.3%) had a history of asthma. Among the participants with a history of both asthma and hay fever, 44.8% developed hay fever first, 34.5% developed asthma first, and 20.7% developed both diseases at the same time. Among the individuals with a history of asthma and nonseasonal allergic rhinitis, 38.5% developed nonseasonal allergic rhinitis first, 30.8% developed asthma first, and 30.8% developed both diseases at the same time. This study further demonstrates the frequent co-existence of asthma and allergic rhinitis. Among asthmatics, allergic rhinitis occurred in 85.7%. Only 14.3% of asthmatics did not have allergic rhinitis. Among individuals with allergic rhinitis, asthma occurred in 21.3%. Also, allergic rhinitis often precedes or occurs at the same time as asthma.