Risk of Cystoid Macular Edema after Cataract Surgery in Retinitis Pigmentosa: An Analysis of United States Claims from 2010 to 2018

Abstract

Cataract surgery is commonly performed to improve vision in patients with retinitis pigmentosa (RP). However, the risk of postoperative cystoid macular edema (CME) in RP remains unclear. Here, we leveraged a large multiyear claims database to estimate the risk of CME after cataract surgery in patients with and without RP. Retrospective multicenter cohort. Patients aged 18 to 65 years who underwent single-phase cataract surgery between January 1, 2020, and December 31, 2018. Identified using the IBM MarketScan claims database. We evaluated the baseline characteristics and outcomes and estimated the hazard ratio (HR) using a multivariable mixed-effects approach. The eyes of patients with RP were categorized as group R1, and those without diagnoses of RP by the time of surgery were categorized as group R0. Incident postoperative CME in the same eye that underwent cataract extraction within 12 months of the procedure. We included 468 123 patients and 615 645 eyes. This included 124 eyes with RP (R1) and 615 521 without RP (R0). The mean ages were 50.5 ± 9.8 years in R1 and 57.9 ± 6.1 years in R0. The cumulative incidence of CME at 12 months was 5.8% (95% confidence interval [CI] 1.2%-10.3%) in R1, and it was 1.1% (95% CI 1.1%-1.2%) in R0. On average, CME was reported in R1 subjects 3.9 weeks later than in R0 subjects (95% CI 2.04-6.5 weeks; P <0.001). The subjects in R1 had 4.83 (95% CI 2.13-10.93, P <0.001) times the risk of CME compared to the subjects in R0. A stratified analysis showed that epiretinal membrane (ERM) decreased the risk of CME in R1 (HR 0.12 [95% CI 0.48-0.97; P= 0.004]) but increased it in R0 (HR, 4.32 [95% CI 3.13-5.95; P<0.001]). The cataract surgery-related risk of CME among patients with RP may be >4 times that among people without RP. Men and individuals aged 18 to 34 and 55 to 65 years may be at the greatest risk, whereas ERM may lower the risk. Further study is warranted to stratify the risk by RP genotype and phenotype and illuminate the natural history, angiographic features, and functional consequences of postoperative CME.