Abstract
Purpose: :
To compare diurnal intraocular pressure (IOP) fluctuation in primary open-angle glaucoma (POAG) patients treated with unfixed-combination latanoprost/timolol, bimatoprost/timolol and travoprost/timolol versus fixed-combination.
Methods: :
A total of 124 eyes of 124 patients with POAG previously treated with unfixed-combination of latanoprost/timolol (n=40), bimatoprost/timolol (n=43) and travoprost/timolol (n=41) for at least 3 months and switched to fixed-combination for compliance reasons were retrospectively evaluated and considered for the analysis. IOP was evaluated during treatment with individual components and 3 month after switch to fixed-combination. IOP was assessed by diurnal curve at 8AM; 11AM; 3PM; 5PM; 8PM. IOP value at any time point was the mean of 2 IOP measurements. Diurnal IOP fluctuation was calculated as highest daily IOP - lowest daily IOP. Fluctuation was also dichotomised: high (> 6 mm Hg), low (< or = 6 mm Hg).
Results: :
Mean diurnal IOP was similar with unfixed and fixed-combination therapy (p > 0.05). For each group diurnal IOP fluctuation was significantly lower in the unfixed-combination compared to fixed-combination (latanoprost/timolol 3.4±1.7 mmHg vs 4.8±2.1 mmHg, bimatoprost/timolol, 3.3±1.4 mmHg vs 4.6±1.9 mmHg, travoprost/timolol 3.3±1.8 mmHg vs 4.9±2.0 mmHg, p < 0.05). The percentage of patients with high diurnal IOP fluctuation increased from 32% to 45% (p < 0.05) after 3 months of fixed-combination therapy.
Conclusions: :
Unfixed-combination of latanoprost/timolol, bimatoprost/timolol or travoprost/timolol resulted in lower diurnal IOP fluctuation and significantly fewer patients with a high fluctuation compared with fixed-combination. Mean IOP showed no difference between concomitant use of individual components and fixed-combination. The unfixed component therapies may have an independent effect on reducing IOP fluctuation in addition to lowering IOP.
Keywords: intraocular pressure