Real-World Outcomes of Selective Laser Trabeculoplasty in the United Kingdom

Abstract

Selective laser trabeculoplasty (SLT) is a common treatment option for managing glaucoma and ocular hypertension. We assessed the real-world effectiveness of SLT and baseline factors associated with treatment success in the United Kingdom. Retrospective observational study of de-identified electronic medical records (Medisoft Glaucoma module [Medisoft Ltd, Leeds, UK]) from 5 UK ophthalmology teaching centers. Adult patients undergoing their first recorded SLT. For bilateral SLT (same day), analyses included 1 randomly selected eye. Patient demographics, procedure details, and clinical outcomes data were extracted. Factors associated with treatment success were assessed using multivariable Cox regression. Change from baseline in intraocular pressure (IOP) and glaucoma medication use at 12 to 18 and 24 to 36 months post-SLT. A Kaplan-Meier survival analysis was also conducted. Failure of SLT was defined as any further glaucoma procedure post-SLT or any of the following at 2 consecutive visits: IOP >21 mmHg, IOP reduction <20% from baseline, or increase in glaucoma medications from baseline. A total of 831 SLT-treated eyes (mean baseline IOP 22.0 mmHg) of 831 patients were analyzed. At 12 to 18 and 24 to 36 months post-SLT, respectively, significant reductions in IOP (-4.2 [95% confidence interval {CI},-4.7 to-3.7] and-3.4 [95% CI,-4.1 to-2.7] mmHg; both P < 0.0001) and significant increases in the number of glaucoma medications (0.13 [95% CI, 0.04-0.23], P= 0.007, and 0.20 [95% CI, 0.06-0.33], P= 0.005) were observed. Survival analysis demonstrated treatment success in 70%, 45%, and 27% of eyes at 6, 12, and 24 months post-SLT, respectively. Higher baseline IOP was strongly associated with treatment success (hazard ratio [HR], 0.67 for baseline IOP >21 mmHg vs. ≤21 mmHg, 95% CI, 0.57-0.80; P < 0.001). Selective laser trabeculoplasty success was not significantly associated with age (P= 0.78), baseline visual field mean deviation (P= 1.00), or concurrent use of IOP-lowering medication (P= 0.52). Most patients initially responded to SLT, but the majority failed within 1 year. Efficacy of SLT was better in patients with higher baseline IOP but did not differ by glaucoma severity or concurrent use of IOP-lowering medication. These findings may help inform which patients are suitable for SLT therapy.