Geographic Disparities in Glaucoma Surgical Care: An Intelligent Research in Sight (IRIS) Registry Analysis

Abstract

Purpose : To quantify differences in glaucoma surgeries based on geography and practice/provider characteristics.

Methods : IRIS Registry data from 2013 – 2020 were included. Cases of micro-invasive glaucoma surgery (MIGS, i.e., iStent microstent, endocyclophotocoagulation, XEN Gel Stent, goniotomy or ab interno trabeculotomy or Trabectome, and canaloplasty) and filtering glaucoma surgery (glaucoma drainage device [GDD] and trabeculectomy) associated with glaucoma diagnosis (with severity stratified by the International Classification of Diseases, Ninth and Tenth Revisions) were selected based on Current Procedure Terminology codes. Urbanization of practice zip codes was classified using Rural-Urban Commuting Area Codes from the United States (US) Department of Agriculture. Associations between procedure counts and practice, provider, and geographic characteristics were assessed using chi-square tests and multivariate logistic regression adjusted for patient demographics (age, gender, and race), glaucoma severity, the interaction between glaucoma severity and urban location, and, as provided by the US Census, zip code population density. Statistical significance was set at p < 0.05.

Results : Most glaucoma surgeries were performed in ophthalmology group practices (55.2%) and urban locations (90.8%). Glaucoma subspecialists performed 72.9% of GDD surgeries, 63.4% of XEN Gel stent surgeries, and 69.0% of trabeculectomies (Table 1). Figure 1 shows the geographic distribution of glaucoma procedures in the mainland US. Urban practice location was associated with a lower likelihood of receiving an iStent (odds ratio [OR] = 0.43, p < 0.0001) and higher odds of receiving endocyclophotocoagulation (OR = 2.23), goniotomy or canaloplasty (OR = 1.57), GDD (OR = 1.85), and trabeculectomy (OR = 1.59) (p < 0.0001). No significant association was found between urban practice location and the likelihood of XEN Gel stent.

Conclusions : Ophthalmology group practices and practices in urban areas account for most glaucoma surgeries. Glaucoma subspecialists performed most filtering glaucoma surgeries. Urban practice location is a significant predictor of receiving most types of MIGS and filtering glaucoma surgery, which may represent barriers to accessing complex surgical glaucoma care for patients outside urban areas.

This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.

 

Table 1

 

Figure 1