Efficacy of Proactive Topical Antihistamine Use in Patients with Seasonal Allergic Conjunctivitis.

INTRODUCTION: Topical antihistamines are often instilled symptomatically to control patients' eye allergy symptoms. The purpose of this study was to evaluate the effectiveness of proactive and as-needed use of antihistamine eye drops in controlling symptoms and to examine whether proactive use may improve quality of life (QOL). METHODS: This was a prospective, multicenter, cohort study in Japan. We classified 418 patients who had developed certain symptoms and used antihistamine eye drops for 2 weeks into two groups: those who used the drops at the required frequency at a fixed time (proactive use) and those who used them as-needed. The Japanese Allergic and Conjunctival Diseases Quality of Life Questionnaire (JACQLQ) and Ten-Item Personality Inventory were used to evaluate QOL and personality. Participants' QOL was evaluated using JACQLQ scores after matching of baseline characteristics using propensity score analysis. RESULTS: After propensity score matching, 115 "proactive" and 115 "as-needed" patients were analyzed. After treatment, in "as-needed" patients, the overall QOL scale was 1.66 (95% CI 1.55-1.78); in "proactive" patients, the overall QOL scale was 1.34 (95% CI 1.23-1.46) and was significantly improved compared with the "as-needed" patients (analysis of covariance, P = 0.002). Furthermore, proactive use significantly alleviated depression (P = 0.03). This improvement of QOL was independent of improvement of the clinical sign scores. CONCLUSION: Proactive use of topical antihistamine may serve as an effective means for improving QOL of patients with seasonal allergic conjunctivitis. TRIAL REGISTRATION: University Hospital Medical Information Network (UMIN) 000039554.