Leukotriene receptor antagonists for allergic rhinitis: a systematic review and meta-analysis

To compare the clinical efficacy of leukotriene receptor antagonists with that of placebo, antihistamines, and nasal corticosteroids in patients with allergic rhinitis or nasal polyposis. We performed a systematic review and meta-analysis of randomized controlled trials of the effectiveness of leukotriene receptor antagonists in patients with rhinitis. Composite daily rhinitis symptom scores (as a percentage of the maximum score) and rhinitis-specific quality of life (unit scores ranging from 0 to 6) were pooled after assessing heterogeneity among studies. The pooled estimates were expressed as weighted mean differences between treatments in a random-effects model. We considered a difference of 10% in nasal score and 0.6 units in quality-of-life score to be clinically relevant. Of the 196 citations, 11 studies on seasonal allergic rhinitis were used in the analysis: eight evaluating leukotriene receptor antagonists alone or in combination with other treatments versus placebo or other treatments (n = 3924) and three evaluating leukotriene receptor antagonists plus an antihistamine (n = 80). Leukotriene receptor antagonists reduced mean daily rhinitis symptom scores (in absolute terms) 5% (95% confidence interval [CI]: 3% to 7%) more than did placebo. However, antihistamines improved the nasal symptoms score 2% (95% CI: 0% to 4%) more than did leukotriene receptor antagonists, and nasal corticosteroids improved the score 12% (95% CI: 5% to 18%) more than did leukotriene antagonists. Leukotriene receptor antagonists significantly improved rhinoconjunctivitis quality of life by 0.3 units (95% CI: 0.24 to 0.36 units) when compared with placebo. There were no randomized controlled trials evaluating the effect of leukotriene receptor antagonists on perennial allergic rhinitis or polyposis. Leukotriene receptor antagonists are modestly better than placebo, as effective as antihistamines, but less effective than nasal corticosteroids in improving symptoms and quality of life in patients with seasonal allergic rhinitis.