Fixed topical combinations in glaucomatous patients and ocular discomfort

Assessment of corneal sublayer thickness changes in glaucoma patients using optical coherence tomography and correlation of epithelial layer thinning with dry eye monitoring

BACKGROUND

In this study, we aimed to assess the central corneal epithelial thickness (CET), central corneal stromal thickness (CST), and total central corneal thickness (CCT) thinning relationships with dry eye development monitoring and underestimated measurement of intraocular pressure (IOP) in primary open-angle glaucoma (POAG) patients treated with timolol, dorzolamide, and brimonidine.

METHODS

This longitudinal cohort study included 106 patients with POAG. All patients underwent a detailed ophthalmic examination. In addition, CET, CST, and CCT were measured using anterior segment optical coherence tomography (AS-OCT). Subsequently, the cohort was divided into three groups based on the therapy administered. The Tomec group received monotherapy with benzalkonium chloride (BAK)-preserved timolol + dorzolamide fixed combination. The Alphagan group received monotherapy with purite-preserved brimonidine, and the Combigan group received monotherapy with BAK-preserved timolol + brimonidine fixed combination.

RESULTS

CET, CST, and CCT did not show a statistically significant decrease in the Alphagan group (p>0.05). However, the Tomec and Combigan groups showed significantly reduced measurements, except for stromal thickness (p<0.05). Finally, a significant positive correlation was found between changes in tear break-up time (TBUT) and CET during the follow-up period (r = 0.637, p = 0.001).

CONCLUSIONS

CET and CCT thinning were higher in the Tomec and Combigan groups than in the Alphagan group. Furthermore, although CCT reduction was significant in the Tomec and Combigan groups, its effect on IOP underestimation was approximately 1%. Furthermore, the positive correlation between CET and TBUT suggests that CET measurement with AS-OCT may also be useful in dry eye monitoring.

Brinzolamide/timolol versus dorzolamide/timolol fixed combinations: A hospital-based, prospective, randomized study

PURPOSE

To compare the efficacy and tolerability of brinzolamide/timolol (BT) and dorzolamide/timolol (DT) fixed combinations on intraocular pressure (IOP) reduction.

METHODS

Patients with primary open angle glaucoma or normal tension glaucoma were randomized to receive either BT or DT. IOPs were measured at baseline, 2 weeks, and 1, 2, and 3 months. The primary outcome measures were the mean change in IOP from baseline at each visit. Secondary outcome measures included the tolerability of each fixed combination.

RESULTS

Seventy-three patients (73 eyes) were included; 37 eyes in BT group and 36 eyes in DT group. Baseline mean IOP were 24.14 ± 4.5 and 29.53 ± 6 mmHg for BT and DT, respectively (P < 0.001). Both BT and DT provided statistically significant mean IOP reductions from baseline values within each group at all study visits (P < 0.001). DT provided greater mean IOP reductions from baseline than BT at each visit which was statistically significant at 2 weeks (P = 0.037). Mean percentage of IOP reduction was 24.35% and 46.33% at 2 weeks (P < 0.001), and 24.65% and 47% at 3 months (P < 0.001) for BT and DT, respectively. Patients' tolerability appeared to be better for DT than for BT with complete ocular comfort without any ocular adverse effects in 31 patients (81.1%) in DT group and 11 patients (29.7%) in BT group (P < 0.001).

CONCLUSION

Both drops provide effective IOP reduction which was greater, and patients were more likely to achieve lower target pressures with DT than with BT.

Efficiency, safety, and patient preference of switching from dorzolamide 1%/timolol 0.5% to brinzolamide 1%/timolol 0.5% while maintaining the prostaglandin F2α analog

Background

We investigated the efficiency, safety and patient preference of switching from dorzolamide 1%/timolol 0.5% to brinzolamide 1%/timolol 0.5% while maintaining the prostaglandin F2α analog.

Methods

We initially enrolled 44 eyes from 44 primary open angle glaucoma patients, and a total of 42 patients completed the study. All patients were under treatment with various prostaglandin F2α analogs and dorzolamide 1%/timolol 0.5%. While maintaining the prostaglandin F2α analog, dorzolamide 1%/timolol 0.5% was switched to brinzolamide 1%/timolol 0.5%. Conjunctival hyperemia, superficial punctate keratopathy, and intraocular pressure (IOP) were evaluated at baseline and at 4, 12, and 24 weeks. Adverse events and patient preferences, measured using a questionnaire at study initiation and at 24 weeks, were also noted.

Results

The IOP was 17.7±1.7, 16.8±2.6, 16.7±2.2, and 16.7±2.4 mmHg at baseline and at 4, 12, and 24 weeks, respectively, with no significant differences in IOP values at any time point (P=0.117, one-way analysis of variance). In addition, no significant differences were found in the incidence of conjunctival hyperemia or SPK score at any time point (all P>0.5, by Kruskal–Wallis test). Based on the evaluation of side effects using the questionnaire, stinging/burning was less common (P=0.042), while blurred vision was more common (P=0.003), after switching to brinzolamide 1%/timolol 0.5%. Regarding patient preferences, 13 patients (31%) preferred dorzolamide 1%/timolol 0.5%, 12 patients (29%) preferred brinzolamide 1%/timolol 0.5%, and 17 patients (40%) preferred neither.

Conclusion

When switching from dorzolamide 1%/timolol 0.5% to brinzolamide 1%/timolol 0.5%, the IOP values and incidence of superficial punctate keratopathy and conjunctival hyperemia were sustained throughout the 24-week observation period, and the patient preferences were similar for the two regimens. However, differences were observed in the ocular sensations of stinging/burning with dorzolamide 1%/timolol 0.5% and blurred vision with brinzolamide 1%/timolol 0.5%.

The impact of timolol maleate on the ocular tolerability of fixed-combination glaucoma therapies

Glaucomatous optic atrophy is the second most common cause of blindness worldwide, and lowering intraocular pressure (IOP) is the only proven method to slow or stop the progression of the disease. Approximately 40% of patients with elevated IOP will require more than one medication to obtain a modest 20% reduction in IOP, and as a result, some patients may require two medications, provided in either two separate bottles or in one bottle with the use of fixed-combination therapies. Each therapy has its own unique safety and efficacy profile. Topical beta-blockers have a particularly favorable ocular-tolerability profile, and several studies of fixed-combination medications containing the beta-blocker timolol maleate have shown a lower prevalence of some ocular adverse events for the fixed-combination therapy compared to the non-beta-blocker individual component. In this review, we examined clinical data pertaining to the ocular surface tolerability of fixed-combination medications containing timolol maleate in comparison to the individual components. In particular, preference was given to prospective, randomized, multicenter trials of 3 months in duration or longer that compared a fixed-combination therapy to monotherapy with the individual components. A review of the literature revealed that some fixed-combination therapies can provide a reduced risk of common side effects compared to their individual components, with conjunctival hyperemia and ocular allergy being less frequent in some timolol-containing fixed-combination therapies. This effect appears to be most significant for latanoprost 0.005%, bimatoprost 0.03%, and brimonidine 0.2%.

Effect of dorzolamide/timolol combination on the visual field in glaucoma

PURPOSE

To evaluate the effect of treatment for 3 years with a dorzolamide/timolol (1%/0.5%) fixed combination (DTFC) on visual field progression in patients with open-angle glaucoma.

PARTICIPANTS

A total of 14 consecutive patients were enrolled who had been previously treated with monotherapy or any combination of a beta blocker, carbonic anhydrase inhibitor, and/or prostaglandin analog for primary open-angle glaucoma (POAG; n=4) or normal-tension glaucoma (NTG; n=10).

METHODS

Patients were switched to DTFC from their prior glaucoma therapy. The IOP was measured at intervals of 4-6 weeks, and the visual fields were examined at least twice a year for 3 years. The annual change of mean deviation (MD slope) was used to quantify visual field loss.

RESULTS

The mean MD value was -5.9±5.0 dB at baseline; it was -5.6±4.8 dB at 12 months, -5.9±5.0 dB at 24 months, and -5.6±5.1 dB at 36 months after switching. The mean MD slope was -0.2±0.8 dB/year before switching and 0.3±1.3 dB/year from baseline to 1 year, -0.3±1.1 dB/year from 1-2 years, and 0.3±0.9 dB/year from 2-3 years after switching. The mean MD slope from baseline to 36 months was correlated with the IOP reduction rate at 36 months after switching. Visual field progression was associated with the IOP reduction rate at 12 months after switching.

CONCLUSION

Switching to DTFC from prior glaucoma therapy improved the MD slope for at least 3 years. Reduction of the IOP after switching to DTFC was effective for delaying visual field progression. Although our study was not nonrandomized and was small in scale, the findings suggest that DTFC might have a beneficial effect on the visual fields in patients with open-angle glaucoma.