Ashapurna Borgohain1 , Soumyadeep Majumdar2 , Soumya Swarup Chatterjee3
BACKGROUND Glaucoma is the leading cause of irreversible blindness in India with around 12 million being affected. Primary Open Angle Glaucoma accounts for majority of these patients. With the choice of drugs to reduce intraocular pressure being plenty, confusion persists on which therapy is best for the patients. Our study aims to compare the efficacy of Fixed-Dose Combination of Brimonidine 0.2% and Timolol 0.5% vs. Monotherapy Brimonidine or Timolol with respect to lowering of intraocular pressure and also its effect on vertical cup disc ratio, mean deviation in automated perimetry, retinal nerve fibre layer thickness and their side effect profile. METHODS This is a prospective, parallel group, open label, randomized intervention trial conducted over 16 months among 180 patients with primary open angle glaucoma attending the glaucoma clinic of the Regional Institute of Ophthalmology, Kolkata. The patients were randomized into three groups 1) Brimonidine 0.2% and Timolol 0.5% fixed-dose combination, twice daily 2) Brimonidine monotherapy, thrice daily and 3) Timolol monotherapy, twice daily and followed up at 1, 3 and 6 months. RESULTS The mean reduction in intra ocular pressure was higher in the fixed-dose combination group (mean reduction - 9.3 ± 2.9) compared to the other two groups (mean change in Timolol group - 5.0 ± 2.0 and mean change in Brimonidine group - 4.5 ± 1.8) at 6 months follow up. The mean loss of retinal nerve fibre layer thickness was significant in the timolol group but not in the other two groups at 6 months. The changes in mean deviation from baseline to 6 months in Humphrey field analysis was not statistically significant in any of the groups. There was statistically significant progression of vertical cup disc ratio from baseline to 6 months in the timolol and brimonidine monotherapy groups. CONCLUSIONS Fixed-Dose Combination of Brimonidine and Timolol had superior efficacy in intraocular pressure reduction in patients with primary open angle glaucoma compared to the monotherapy with brimonidine or timolol. Fixed-Dose combination also decreased the progression of glaucoma compared to the other groups
