Abstract
Abstract: :
Purpose: To assess the frequency of preservatives ocular toxicity in patients treated with non selective beta-blockers. Methods: A prospective, cross-over, double-masked, randomised clinical study was conducted on 20 primary open angle glaucoma or ocular hypertension patients treated with timolol maleate 0.5%. After 3 weeks of wash-out, patients were randomly divided in two groups: group 1 started therapy with preservatives free timolol 0.5% and group 2 with preserved timolol 0.5% eye drops. After 60 days of treatment and 3 more weeks of wash-out, each group switched to the other therapy. Intraocular pressure, interleukine 1-ß tears concentration and ocular signs and symptoms were evaluated before beginning each therapy and after 30 and 60 days of treatment. Wilcoxon signed ranks test and Mann-Whitney U test were used to analyse data. Results: either after 30 or after 60 days of therapy, in both groups, a significant higher interleukine 1-ß tears concentration was found in patients treated with preserved timolol 0.5% therapy if compared with patients treated with preservatives free eye drops (30 days. group1: 402.8±253.2 pg/ml and 672.9±471 pg/ml, p=0.04. Group 2: 1163.5±522.7 pg/ml and 376.7±149.9 pg/ml, p=0.005) (60 days. group1: 329.5±135.5 pg/ml and 1446.7±494.7 pg/ml, p=0.005. Group 2: 1138.6±552.1 pg/ml and 279.9±155.6 pg/ml, p=0.005). Between signs and symptoms considered burning, foreign body sensation and reduced break up time were significantly more prevalent after 30 days of therapy during preserved timolol 0.5% treatment in both groups. The same signs plus ocular hyperemia and blepharitis in both groups and superficial punctuate keratitis only in group 2 were more prevalent after 60 days of therapy during preserved timolol 0.5% treatment. Both treatments were equally effective on intraocular pressure reduction during the study. Conclusions:The use of preservative free timolol is associated with lower tears levels of interleukine 1-ß and allows to reduce the occurrence of signs and symptoms of ocular inflammation during the long-term pharmacological glaucoma therapy.
Keywords: cornea: tears/tear film/dry eye • cytokines/chemokines • drug toxicity/drug effects