Two-Year Visual Field Outcomes of the Treatment of Advanced Glaucoma Study (TAGS)

Evaluating Primary Treatment for People with Advanced Glaucoma: Five-Year Results of the Treatment of Advanced Glaucoma Study

PURPOSE

To determine whether primary trabeculectomy or medical treatment produces better outcomes in terms of quality of life (QoL), clinical effectiveness, and safety in patients with advanced glaucoma.

DESIGN

Multicenter randomized controlled trial.

PARTICIPANTS

Between June 3, 2014, and May 31, 2017, 453 adults with newly diagnosed advanced open-angle glaucoma in at least 1 eye (Hodapp classification) were recruited from 27 secondary care glaucoma departments in the United Kingdom. Two hundred twenty-seven were allocated to trabeculectomy, and 226 were allocated medical management.

METHODS

Participants were randomized on a 1:1 basis to have either mitomycin C-augmented trabeculectomy or escalating medical management with intraocular pressure (IOP)-reducing drops as the primary intervention and were followed up for 5 years.

MAIN OUTCOME MEASURES

The primary outcome was vision-specific QoL measured with the 25-item Visual Function Questionnaire (VFQ-25) at 5 years. Secondary outcomes were general health status, glaucoma-related QoL, clinical effectiveness (IOP, visual field, and visual acuity), and safety.

RESULTS

At 5 years, the mean ± standard deviation VFQ-25 scores in the trabeculectomy and medication arms were 83.3 ± 15.5 and 81.3 ± 17.5, respectively, and the mean difference was 1.01 (95% confidence interval [CI], -1.99 to 4.00; P = 0.51). The mean IOPs were 12.07 ± 5.18 mmHg and 14.76 ± 4.14 mmHg, respectively, and the mean difference was -2.56 (95% CI, -3.80 to -1.32; P < 0.001). Glaucoma severity measured with visual field mean deviation were -14.30 ± 7.14 dB and -16.74 ± 6.78 dB, respectively, with a mean difference of 1.87 (95% CI, 0.87-2.87 dB; P < 0.001). Safety events occurred in 115 (52.2%) of patients in the trabeculectomy arm and 124 (57.9%) of patients in the medication arm (relative risk, 0.92; 95% CI, 0.72-1.19; P = 0.54). Serious adverse events were rare.

CONCLUSIONS

At 5 years, the Treatment of Advanced Glaucoma Study demonstrated that primary trabeculectomy surgery is more effective in lowering IOP and preventing disease progression than primary medical treatment in patients with advanced disease and has a similar safety profile.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Estimating the Distribution of True Rates of Visual Field Progression in Glaucoma

Purpose

The purpose of this study was to estimate the distribution of the true rates of progression (RoP) of visual field (VF) loss.

Methods

We analyzed the progression of mean deviation over time in series of ≥ 10 tests from 3352 eyes (one per patient) from 5 glaucoma clinics, using a novel Bayesian hierarchical Linear Mixed Model (LMM); this modeled the random-effect distribution of RoPs as the sum of 2 independent processes following, respectively, a negative exponential distribution (the "true" distribution of RoPs) and a Gaussian distribution (the "noise"), resulting in a skewed exGaussian distribution. The exGaussian-LMM was compared to a standard Gaussian-LMM using the Watanabe-Akaike Information Criterion (WAIC). The random-effect distributions were compared to the empirical cumulative distribution function (eCDF) of linear regression RoPs using a Kolmogorov-Smirnov test.

Results

The WAIC indicated a better fit with the exGaussian-LMM (estimate [standard error]: 192174.4 [721.2]) than with the Gaussian-LMM (192595 [697.4], with a difference of 157.2 [22.6]). There was a significant difference between the eCDF and the Gaussian-LMM distribution (P < 0.0001), but not with the exGaussian-LMM distribution (P = 0.108). The estimated mean (95% credible intervals, CIs) "true" RoP (-0.377, 95% CI = -0.396 to -0.359 dB/year) was more negative than the observed mean RoP (-0.283, 95% CI = -0.299 to -0.268 dB/year), indicating a bias likely due to learning in standard LMMs.

Conclusions

The distribution of "true" RoPs can be estimated with an exGaussian-LMM, improving model accuracy.

Translational Relevance

We used these results to develop a fast and accurate analytical approximation for sample-size calculations in clinical trials using standard LMMs, which was integrated in a freely available web application.

Longitudinal evaluation of advanced glaucoma: ten year follow-up cohort study

This study focused on patients with advanced open-angle glaucoma (OAG) and aimed to identify key factors for monitoring them. We included 127 such patients who were followed for seven years or more, undergoing annual ophthalmic examinations. Glaucoma progression was defined as a deterioration in either structure or function. The progression rates and risk factors were evaluated. The patients were divided into upper- and lower-half subgroups based on the reduction in intraocular pressure (IOP) from the baseline. Over an 11-year period, glaucoma progression was detected in 59 eyes (46.5%). The rate of change in mean deviation (MD) was - 0.43 dB/year for the entire population; - 0.67 dB/year for progressors; and - 0.20 dB/year for non-progressors. Hypertension and disc hemorrhage (DH) were more common in progressors compared to non-progressors (45.8 vs. 23.5%, 11.9 vs. 1.5%; P = 0.008 and P = 0.016). Multivariate Cox's proportional hazard model revealed that the presence of DH and a better baseline MD were associated with glaucoma progression. Additionally, patients with a higher percentage reduction in IOP (> 20.94%) had a lower risk of progression compared to those with less reduction. Inadequate IOP reduction, better baseline MD, presence of DH, and lower central corneal thickness were identified as risk factors for progression in advanced OAG patients.

[Real-world outcomes of glaucoma surgical procedures for open-angle glaucoma]

This article provides an overview of real-world outcomes in glaucoma surgical procedures. While randomized clinical trials provide valuable insights, they do not fully reflect real-world clinical practice. Real-world studies enable the evaluation of outcomes in uncontrolled settings and play a crucial role in counselling and decision-making for glaucoma treatment. By examining real-world data the article aims to identify rare adverse events that may go unnoticed in controlled clinical trials. The focus is on assessing the effectiveness and safety of glaucoma surgical procedures beyond the controlled trial setting.

Long-term Impact of Immediate Versus Delayed Treatment of Early Glaucoma: Results From the Early Manifest Glaucoma Trial

PURPOSE

To compare long-term visual outcomes in the 2 arms of the Early Manifest Glaucoma Trial (EMGT) and determine if delayed treatment was associated with a penalty in terms of visual function.

DESIGN

Long-term follow-up of a prospective, randomized controlled clinical trial.

METHODS

EMGT was carried out at 2 centers in Sweden; 255 subjects with newly detected, untreated glaucoma were randomized to immediate treatment with topical betaxolol and argon laser trabeculoplasty or to no initial treatment as long as no progression was detected. Subjects were followed prospectively with standard automated perimetry, visual acuity measurements, and tonometry for up to 21 years. Outcomes included vision impairment (VI), the perimetric mean deviation (MD) index and rate of progression, and visual acuity.

RESULTS

At study end, percentages of eyes with VI or blindness were slightly higher in the treated group than in the untreated control group, 12.1% vs 11.0%, and 9.4.% vs 6.1% respectively, as were subjects with VI in at least one eye, 19.5% vs 18.7%. The differences were not statistically significant, nor were cumulative incidences of VI in at least one eye. The control group had more field loss than the treatment group, with median MD in the worse eye of -14.73 dB vs -12.85 dB, and rate of progression of -0.74 vs -0.60 dB/y, which was not statistically significant. Differences in visual acuity were minimal.

CONCLUSIONS

Delaying treatment did not result in serious penalties. VI occurred at similar proportions in both treatment arms with a slight preponderance in the treatment group, whereas visual field damage was slightly higher in the control group.

Five-Year Visual Field Outcomes of the HORIZON Trial

PURPOSE

To compare visual field (VF) progression between glaucoma patients receiving cataract surgery alone (CS) or with a Hydrus microstent (CS-HMS).

DESIGN

Post hoc analysis of VF data from the HORIZON multicenter randomized controlled trial.

METHODS

A total of 556 patients with glaucoma and cataract were randomized 2:1 to either CS-HMS (369) or CS (187) and followed up for 5 years. VF was performed at 6 months and then every year after surgery. We analyzed data for all participants with at least 3 reliable VFs (false positives < 15%). Average between-group difference in rate of progression (RoP) was tested using a Bayesian mixed model and a 2-sided Bayesian P value <.05 (main outcome). A multivariable model measured the effect of intraocular pressure (IOP). A survival analysis compared the probability of global VF sensitivity dropping by predefined cutoffs (2.5, 3.5, 4.5, and 5.5 dB) from baseline.

RESULTS

Data from 352 eyes in the CS-HMS arm and 165 in the CS arm were analyzed (2966 VFs). The mean RoP was -0.26 dB/y (95% credible interval -0.36, -0.16) for CS-HMS and -0.49 dB/y (95% credible interval -0.63, -0.34) for CS. This difference was significant (P = .0138). The difference in IOP only explained 17% of the effect (P < .0001). Five-year survival analysis showed an increased probability of VF worsening by 5.5 dB (P = .0170), indicating a greater proportion of fast progressors in the CS arm.

CONCLUSIONS

CS-HMS has a significant effect on VF preservation in glaucoma patients compared with CS alone, reducing the proportion of fast progressors.