Asthma and allergic rhinitis are thought to be associated, but the exact relationship is not clear. This study investigated the onset of asthma in patients with allergic and non-allergic rhinitis, analysing follow-up data from the European Community Respiratory Health Survey (ECRHS).

Adults were randomly selected from responders to a questionnaire in ECRHS I. These individuals provided a blood sample for IgE measurements, underwent skin prick testing, lung function assessment and bronchial responsiveness challenge tests. A total of 6461 participants free of asthma at baseline constituted the study population in this analysis and were divided into four groups: atopy but no rhinitis (n = 704); non-allergic rhinitis (n = 1377); allergic rhinitis (n = 1217) and control (neither of above) (n = 3163).

During the 8.8 years of follow-up the cumulative incidence of asthma was higher in patients with allergic rhinitis and those with non-allergic rhinitis. The relative risk of asthma was 3.53 for those with allergic rhinitis and 2.71 for patients with non-allergic rhinitis (after controlling for baseline demographics). Associations between allergic rhinitis and asthma incidence were stronger in those sensitised to several allergens, and sensitisation to mites was associated independent of other allergens. Atopic patients without rhinitis did not have a significantly higher risk than controls of developing asthma.

The authors conclude that rhinitis, even in the absence of atopy, is a powerful predictor of adult onset asthma. Prevention of asthma through identification and management of risk factors, particularly in a preclinical phase of the disease, is a priority. This study opens interesting avenues for future investigations as treatment of allergic rhinitis may be effective in reducing the incidence of asthma.

▸ Shaaban R, Zureik M, Soussan D, et al. Rhinitis and onset of asthma: a longitudinal population-based study. Lancet 2008;372:1049–57.