Background We have previously proposed that, compared with rhinitis alone, theconstellation of upper and lower airway allergic disease is a manifestation of a more severe form of a syndrome affecting the entire airway. If this is correct, not only the lower, but also the upper airways of patients with asthma and rhinitis should demonstrate more abnormalities compared with patients with rhinitis alone, including higher sensitivity to irritant factors.
Objective To test the hypothesis that, a previously well-studied natural nasal stimulus, cold, dry air (CDA), produces a stronger response in subjects with allergic rhinitis (AR) and asthma compared with subjects with AR alone.
Methods We performed nasal provocation with CDA on 24 individuals with asthma and rhinitis and 17 with rhinitis alone. Prior to and after the challenge, nasal symptoms were recorded using visual analogue scales and nasal lavages were performed to determine histamine and lysozyme levels.
Results The two groups reacted differently to CDA: after the challenge, patients with rhinitis and asthma reported significantly higher scores for nasal congestion, rhinorrhea and lacrimation. Also in this group, significant increases in histamine and in lysozyme levels in nasal lavage fluids were induced by CDA. In subjects with rhinitis alone, CDA failed to increase histamine or lysozyme levels above baseline. The CDA-induced change from baseline in histamine was significantly higher in the patients with rhinitis and asthma, compared with the rhinitis-only group.
Conclusion Patients with AR and asthma have stronger nasal responsiveness to CDA compared with patients with rhinitis alone. This observation is consistent with the notion that compared with rhinitis alone, the presence of asthma and rhinitis signifies a higher degree of functional abnormality of the entire airway.