Asthma and allergic rhinitis have similar pathophysiologic mechanisms and are most likely forms of the same allergic inflammatory syndrome. The presence of allergic rhinitis usually precedes asthma and is a potential risk factor for developing asthma. Attempts have been made to better understand the connection between allergic rhinitis and asthma. However, few studies have evaluated the impact allergic rhinitis treatment can have on controlling asthma. There are conflicting recommendations by various organizations regarding whether controlling allergic rhinitis is necessary for asthma management. Stelmach and colleagues evaluated the influence that inhaled or topical nasal steroids have on the treatment of patients with rhinitis and asthma.

The trial was a double-blind, parallel, three-group study of patients with mild to moderate persistent asthma and allergic rhinitis. To enroll in the study, each participant must not have undergone corticosteroid treatment for the previous three months. Published guidelines were used to determine mild to moderate persistent asthma and allergic rhinitis diagnoses. Some of the inclusion criteria were a positive skin-prick test for one or more allergens, nonsmokers or former smokers, no respiratory infections within the previous four weeks, and no current use of theophylline or leukotrienes. The three treatment groups included persons who received topical nasal steroids alone, inhaled steroids alone, or both topical nasal and inhaled steroids for a 16-week period. Those who received topical nasal steroids or inhaled steroids only received an inhaled or topical nasal placebo device. The participants were evaluated using symptom scores, pulmonary function testing, and bronchial hyperresponsiveness at baseline, four weeks, and 16 weeks.

Of the 59 participants in the study, 21 received topical nasal steroids, 18 received inhaled steroids, and 20 received both. In all three groups there was a significant decline in nasal and pulmonary symptoms at four weeks, and an even greater improvement at 16 weeks. Improvements also were noted in the pulmonary function tests and bronchial hyperresponsiveness in all three groups throughout the study. In all three groups, absence from work, nighttime cough, and emergency department visits significantly decreased when compared with baseline.

The authors conclude that the treatment of allergic rhinitis is an important component of asthma management and that failure to treat allergic rhinitis may have a negative impact on asthma control. They add that, in some patients, asthma control may be obtained by treating allergic rhinitis with topical nasal steroids without the need for inhaled steroids.