It has been suggested for nearly twenty years that nasal sprays containing corticosteroids might improve asthma outcomes in people suffering from both asthma and rhinitis. Intranasal corticosteroids had few side effects in people with mild asthma, but the improvements in symptoms scores and lung function could have arisen by chance. Intranasal corticosteroids may be a promising alternative treatment for patients with rhinitis and mild asthma. More research is needed before considering changing the current practice of prescribing corticosteroids delivered by oral inhalers for asthma, and by nasal sprays for rhinitis.
Vollständige Zusammenfassung lesen
Allergic rhinitis and asthma are mediated by similar allergic mechanisms. They may represent two manifestations of the same united airway disease and therefore intranasal corticosteroids (INCS) could improve asthma. Nevertheless none of the asthma guidelines have advocated intranasal corticosteroids for asthma.
Zielsetzungen
To assess the efficacy of intranasal corticosteroids on asthma outcomes in people with rhinitis and asthma.
Suchstrategie
We searched the Cochrane Airways Group trials register, the Cochrane Central Register of Controlled Trials (Issue 1, 2003), MEDLINE and reference lists of articles. We also contacted researchers in the field. The last search was conducted in March 2004.
Auswahlkriterien
Randomised controlled trials comparing intranasal corticosteroids to intranasal placebo or to other traditional asthma treatments were included. Intrabronchial corticosteroids were not allowed but a device combining intranasal and intrabronchial corticosteroid was considered as being a primary INCS technique and was therefore also compared to placebo.
Datensammlung und ‐analyse
Two reviewers independently assessed trial quality and extracted data. Study authors were contacted for additional information. Quality assessment for the 14 eligible studies was performed using the Jadad score and by ranking allocation concealment. Statistical analysis for continuous data was done by weighted mean difference or standardised mean difference.
Hauptergebnisse
Fourteen trials involving 477 people were included. Meta-analysis for asthma outcomes failed to show a statistically significant benefit of INCS in asthma. However, for symptom scores and forced expiratory volume in one second, the trend favoured a beneficial effect of INCS. For asthma symptom scores (two parallel studies), the standardised mean difference was 0.61 (95% confidence interval (CI) -0.04 to 1.26). Meta-analysis for forced expiratory volume in one second (five parallel studies) gave a standardised mean difference of 0.31 (95% CI -0.04 to 0.65). In the parallel studies, meta-analysis of peak expiratory flow gave a standardised mean difference of -0.10 Litres/min (95% CI -0.55 to 0.35) for mean peak flow (three studies). Meta-analysis for methacholine airway responsiveness (three parallel studies) showed a standardised mean difference of -0.20 (-95% CI 0.64 to 0.24).
Schlussfolgerungen der Autoren
Intranasal corticosteroids were well tolerated. While INCS tended to improve asthma symptoms and forced expiratory volume in one second, the results did not reach significance. The combination of intranasal plus intrabronchial corticosteroids should remain the current clinical practice until more research is done.
