Abstract
Purpose :
To identify baseline and inter-current factors associated with achievement and maintenance of target intraocular pressure (IOP) with one or more selective laser trabeculoplasty (SLT) treatments in Afro-Caribbean patients with open-angle glaucoma (OAG) washed out of all prior IOP-lowering medications pre-SLT.
Methods :
This is a post hoc analysis of data collected through ≥3 years of follow-up after initial bilateral SLT in 72 subjects from St. Lucia or Dominica participating in the West Indies Glaucoma Laser Study. The 3-year treatment success rate was determined by survival analysis, with success defined as maintenance of target IOP (≥20% reduction from pre-treatment baseline) at last follow-up after 1 or more SLT treatments with no other interventions for IOP reduction (medications or surgery). SLT was repeated as needed when IOP exceeded target IOP on 2 consecutive visits. A multivariable logistic regression model was constructed for each eye to identify baseline and inter-current factors associated with treatment outcomes. Right and left eyes were analyzed separately. Factors included in the models included age, gender, site (St. Lucia vs. Dominica), number of pre-SLT medications before washout, use of a prostaglandin pre-SLT, baseline IOP after washout, central corneal thickness, visual field mean deviation, vertical cup-disc ratio, presence of anterior chamber inflammatory cells 1 week after first SLT, and IOP 6 weeks and 3 months after first SLT. Factors significant in either eye at p=0.2 in bivariate analysis were included in the final multivariable model in both eyes.
Results :
Survival rates through 3 years of follow-up were 70.0% and 74.2% in right eyes (RE) and left eyes (LE), respectively. None of the factors evaluated was significant in the final model for right eyes, and only site was significant in the final model for left eyes (odd ratio 6.3 favoring St. Lucia, 95% confidence interval 1.05-37.9, p=0.0437).
Conclusions :
SLT therapy, repeated as needed, achieved and maintained target IOP for most eyes in the WIGLS cohort. The finding that site was of marginal significance in left eyes and insignificant in right eyes suggests negligible clinical significance of this observation. In the absence of factors related to success or failure of SLT, the procedure has broad applicability in this population.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.