Two-Year Visual Field Outcomes of the Treatment of Advanced Glaucoma Study (TAGS)
Giovanni Montesano, Giovanni Ometto, Anthony King, David F. Garway‐Heath, David P. Crabb
Abstract
Purposeto compare visual field (VF) progression between the 2 arms of the Treatment of Advanced Glaucoma Study (TAGS).DesignPost hoc analysis of VF data from a 2-arm, multicenter, randomized controlled clinical trial.MethodsA total of 453 patients with newly diagnosed advanced open-angle glaucoma in at least 1 eye from 27 centers in the United Kingdom were randomized to either trabeculectomy (n = 227) or medication in their index eye (n = 226) and followed-up for 2 years with 2 24-2 VF tests at baseline, 4, 12, and 24 months. Data were analyzed for participants with a reliable VF (false positive rate < 15%) at baseline and at least 2 other time points. Average difference in rate of progression (RoP) was analyzed using a hierarchical Bayesian model. Time for each eye to progress from baseline beyond specific cut-offs (0.5, 1, 1.5, and 2 dB) was compared using survival analysis.ResultsThis study analyzed 211 eyes in the trabeculectomy first arm and 203 eyes in the medication first arm. The average RoP (estimate [95% credible intervals]) was –0.59 [–0.88, –0.31] dB/year in the medication first arm and –0.40 [–0.67, –0.13] dB/year in the trabeculectomy first arm. The difference was not significant (Bayesian P-value = .353). More eyes progressed in the medication first arm, but this difference was not significant.ConclusionsThere was no significant difference in the average RoP at 2 years. to compare visual field (VF) progression between the 2 arms of the Treatment of Advanced Glaucoma Study (TAGS). Post hoc analysis of VF data from a 2-arm, multicenter, randomized controlled clinical trial. A total of 453 patients with newly diagnosed advanced open-angle glaucoma in at least 1 eye from 27 centers in the United Kingdom were randomized to either trabeculectomy (n = 227) or medication in their index eye (n = 226) and followed-up for 2 years with 2 24-2 VF tests at baseline, 4, 12, and 24 months. Data were analyzed for participants with a reliable VF (false positive rate < 15%) at baseline and at least 2 other time points. Average difference in rate of progression (RoP) was analyzed using a hierarchical Bayesian model. Time for each eye to progress from baseline beyond specific cut-offs (0.5, 1, 1.5, and 2 dB) was compared using survival analysis. This study analyzed 211 eyes in the trabeculectomy first arm and 203 eyes in the medication first arm. The average RoP (estimate [95% credible intervals]) was –0.59 [–0.88, –0.31] dB/year in the medication first arm and –0.40 [–0.67, –0.13] dB/year in the trabeculectomy first arm. The difference was not significant (Bayesian P-value = .353). More eyes progressed in the medication first arm, but this difference was not significant. There was no significant difference in the average RoP at 2 years.