Non–Response to ß–Blocker Topical Application in Normal–Tension–Glaucoma

Abstract

Abstract: : Purpose: This prospective study investigated the intraocular pressure reduction rate(IOP–RR) and responsiveness of four types of topical ß–blocker in normal tension glaucoma(NTG). Methods: Eighty NTG patients (80 eyes, male 29 eyes and female 51 eyes, mean age 60.4±13.4 years old) were divided into four groups, each of which received only one type of ß–blocker for 3 months. The ß–blockers used in this study were carteolol hydrochloride(group A), nipradilol(group B), betaxolol hydrochloride(group C) and timolol maleate(group D). After 1, 2 and 3 months of administration twice a day, IOP–RR and non–responder incidence were examined. Non–responders were defined as those with IOP–RR of 10% or less. The effects among the 4 types of ß–blocker were statistically analyzed . IOP–RR formula was ( baseline IOP–current IOP)/baseline IOP*100. Results: There was no significant difference with age and baseline IOP in all groups. Two, four, one and three patients dropped out in groups A, B, C and D respectively, so statistical analysis was done excluding these patients. Respective IOP–RRs for group A, B, C and D were 7.7±10.1, 10.3±8.3, 8.9±15.2, 12.8±1.8% at 1 month, and 9.2±20.7, 9.5±15.2, 11.2±14.7 and 14.5±14.8% at 3 months. Respective non–responder incidence was 61.1, 37,5, 42.1 and 35.3% at 1 month, and 61.1, 52.9, 47.4 and 41.2% at 3 months. There were no significant differences with IOP–RR (Tukey–Kramer test) and non–responder incidence( Chi–square test) among the 4 groups. Conclusions: Regarding IOP–RR and non–responder incidence among NTG patients, there were no statistically significant differences between 4 types of ß–blockers.

Keywords: intraocular pressure • clinical (human) or epidemiologic studies: prevalence/incidence • clinical (human) or epidemiologic studies: outcomes/complications