West Indies Glaucoma Laser Study (WIGLS)-2: Predictors of Selective Laser Trabeculoplasty Efficacy in Afro-Caribbeans With Glaucoma

J Glaucoma. 2018 Oct;27(10):845-848. doi: 10.1097/IJG.0000000000001018.

Abstract

Purpose: To identify factors associated with intraocular pressure (IOP) reduction following selective laser trabeculoplasty (SLT) in Afro-Caribbean people with primary open-angle glaucoma (POAG).

Design: This was a prospective stepped-wedge study.

Methods: Data were drawn from 72 Afro-Caribbean subjects with POAG participating in the ongoing West Indies Glaucoma Laser Study. Multivariable mixed-model analysis was utilized to develop a predictive model for percent IOP reduction 12 months following SLT. Putative factors (age, sex, site, baseline IOP, prior use of prostaglandin therapy, number of prewashout IOP-lowering medications, central corneal thickness, severity of glaucoma, duration of follow-up, and signs of acute postoperative inflammation) were evaluated in bivariate analysis. Factors significant at P≤0.2 were included in the final model. Right and left eye data were modeled separately.

Results: At month 12 following SLT, mean IOP reductions in the West Indies Glaucoma Laser Study were 6.2 to 6.5 mm Hg (29.7% to 31.0%) in right and left eyes. The only factor significant in both eyes (P=0.0005 in right eyes and P<0.0001 in left eyes) was time, with IOP reductions being greatest at month 3 and declining slightly over time through month 12. Vertical cup-disc ratio (P=0.006) and prior prostaglandin therapy (P=0.004) were significant only in right eyes, and central corneal thickness (P=0.014) was significant only in left eyes. Factors significant only unilaterally did not approach significance in fellow eyes, suggesting the possibility that these represent type 1 errors. Site (St. Lucia vs. Dominica) was not a significant factor, establishing generalizability of these treatment outcomes to a broader population of African-derived people.

Conclusions: This analysis did not identify any subject-specific factors consistently predictive of therapeutic response to SLT. Of note, no factors predicted a suboptimal response. These findings favorably position SLT for broad application as primary therapy in African-derived people with POAG.

Trial registration: ClinicalTrials.gov NCT02375009.

MeSH terms

  • African Continental Ancestry Group / ethnology*
  • Aged
  • Caribbean Region / ethnology
  • Ethnic Groups
  • Female
  • Glaucoma, Open-Angle / ethnology*
  • Glaucoma, Open-Angle / physiopathology
  • Glaucoma, Open-Angle / surgery*
  • Humans
  • Intraocular Pressure / physiology
  • Laser Therapy / methods*
  • Male
  • Middle Aged
  • Prospective Studies
  • Trabeculectomy / methods*
  • Treatment Outcome
  • West Indies / epidemiology

Associated data

  • ClinicalTrials.gov/NCT02375009