Factors Associated with Interventions after Laser Peripheral Iridotomy for Primary Angle-Closure Spectrum Diagnoses

Abstract

To assess factors associated with receipt of subsequent medical, laser, or surgical interventions after laser peripheral iridotomy (LPI). Retrospective review. A total of 1271 eyes in 692 subjects with narrow angles (NAs) that were treated with LPI. Demographic and clinical factors associated with primary angle-closure (PAC) or PAC glaucoma (PACG) versus PAC suspect (PACS) diagnosis and use of glaucoma medications at the time of LPI, as well as factors predictive of subsequent addition of glaucoma medications, and receipt of selective laser trabeculoplasty (SLT), cataract surgery, and glaucoma surgery were assessed using logistic regression with generalized estimating equations. Kaplan-Meier curves and Cox proportional-hazards regression analysis were used to assess baseline factors affecting the time to SLT, cataract surgery, or glaucoma surgery. Diagnosis of PAC/PACG and medical, laser, or surgical interventions after LPI. African Americans (odds ratio [OR], 2.12; P < 0.001) were significantly more likely than whites to have PAC/PACG than PACS and to already be taking glaucoma medications (OR, 2.25, P < 0.001) at the time of LPI. In multivariable logistic regression analysis, African Americans were significantly more likely to be prescribed additional glaucoma medications after LPI (OR, 1.73; P= 0.025) and receive glaucoma surgery (OR, 2.7; P= 0.007), but were less likely to receive SLT (OR, 0.37; P= 0.009). In multivariate Cox proportional-hazards regression analysis, African Americans had longer time to SLT than whites (hazard ratio [HR], 0.41; P= 0.022), but a shorter time to glaucoma surgery (HR, 2.57; P= 0.004). There was no significant association between race and the likelihood of cataract surgery or time to cataract surgery (P > 0.10). African Americans were more likely than whites to carry a diagnosis of PAC or PACG at the time of LPI and were significantly more likely to be prescribed additional glaucoma medications and require glaucoma surgery after LPI. Improved screening methods that target African Americans with NAs are needed so that preventive interventions such as LPI can be performed earlier to decrease the risk of progression.