Leukotriene receptor antagonists in allergic eye disease: a systematic review and meta-analysis

Allergic eye diseases are common and cause significant morbidity. Leukotrienes are implicated in the pathogenesis of seasonal and perennial allergic conjunctivitis (AC), commonly seen in conjunction with allergic rhinitis, and in vernal keratoconjunctivitis and atopic keratoconjunctivitis.

To assess the available evidence for an effect of leukotriene receptor antagonists (LTRAs) on the ocular symptoms of allergic eye diseases.

Selected studies, identified with systematic review search methods, were single/double-blind, randomized, controlled trials that compared LTRAs with other common treatments.

Eighteen trials, using the LTRA montelukast (in AC only), were identified. Six studies were suitable for meta-analysis, in patients with seasonal AC [treated over a 2-week period, symptoms scored 0 (mild) to 3 (severe)]. These trials were at low risk of bias without significant heterogeneity. Six trials were analyzed and showed that montelukast improved patients' ocular symptoms to a greater extent than placebo, with a difference in mean change-from-baseline score of -0.10 (95% CI, -0.14 to -0.07; P < .00001). Three trials compared montelukast with oral antihistamine. The difference in mean change-from-baseline score was 0.08 (95% CI, 0.02 to 0.14; P = .007), in favor of antihistamines. Two trials compared montelukast and oral antihistamine with placebo. The difference in mean change-from-baseline score was -0.30 (95% CI, -0.38 to -0.21; P < .00001), in favor of combination treatment.

In seasonal AC LTRAs are more efficacious than placebo but less efficacious than oral antihistamines in adult patients. Clinical trials should be conducted to determine whether combination treatment with LTRA and oral antihistamine has a synergistic effect. Further research is required to clarify the role of LTRAs in other allergic eye diseases.