Interactions between rhinitis and asthma

Allergic rhinitis is present in up to 75% of patients with asthma, and in longitudinal follow-up, patients with allergic rhinitis are three times more likely to develop asthma as compared with subjects without allergic rhinitis. In experimental nasal challenges with allergen followed by nasal biopsies at 24 hours, there is positive staining for interleukin-5, eotaxin, intracellular adhesion molecule 1, vascular cell adhesion molecule 1, and E-selectin. Concurrently obtained bronchial biopsy specimens show eosinophils and intracellular adhesion molecule 1, vascular cell adhesion molecule 1, and E-selectin. There is increasing evidence for bone marrow stimulation by either seasonal or experimental allergen exposure resulting in an increase in bone marrow and peripheral blood progenitors for eosinophils/basophils. These cells then could populate the nose and lungs. From a therapeutic perspective, intranasal beclomethasone dipropionate and flunisolide have been reported to reduce the symptoms of asthma in patients with ragweed-induced allergic rhinitis. Conversely, high-dose orally inhaled budesonide has been shown to reduce some of the symptoms of allergic rhinitis. Finally, first reported in 1968 and then not until 1997, there is evidence that allergen vaccine immunotherapy, when administered to children with allergic rhinitis, may prevent the development of asthma or at least reduce its likelihood of occurring.