Erythropoiesis-Stimulating Agents and the Risk of Vision-Threatening Diabetic Retinopathy

Animal studies have suggested that Erythropoiesis-Stimulating Agents (ESAs) may increase vascular endothelial growth factor (VEGF)-related retinopathies, but this effect is unclear in humans. This study evaluates the risk of vision-threatening diabetic retinopathy (VTDR), defined as either diabetic macular edema (DME) or proliferative diabetic retinopathy (PDR), in patients exposed to an ESA.

Two analyses were performed. First, a retrospective matched-cohort study was designed using a de-identified commercial and Medicare Advantage medical claims database. The ESA cohort of non-proliferative diabetic retinopathy patients who were new users of an ESA from 2000 to 2022 was matched to controls up to a 3:1 ratio. Exclusion criteria included less than 2 years in the plan, history of VTDR or history of other retinopathy. Multivariable Cox proportional hazards regression with inverse proportional treatment weighting (IPTW) was used to assess the hazard of developing VTDR, DME, and PDR. The second analysis was a self-controlled case series (SCCS) evaluating the incidence rate ratios (IRR) of VTDR during 30-day periods before and after initiating an ESA.

After inclusion of 1502 ESA-exposed patients compared with 2656 controls, IPTW-adjusted hazard ratios found the ESA cohort had an increased hazard of progressing to VTDR (HR = 3.0 95%CI:2.3-3.8;p < .001) and DME (HR = 3.4,95%CI:2.6-4.4,p < .001), but not PDR (HR = 1.0,95%CI:0.5-2.3,p = .95). Similar results were found within the SCCS which demonstrated higher IRRs for VTDR (IRRs = 1.09-1.18;p < .001) and DME (IRRs = 1.16-1.18;p < .001), but not increased IRRs in PDR (IRR = 0.92-0.97,p = .02-0.39).

ESAs are associated with higher risks for VTDR and DME, but not PDR. Those studying ESAs as adjunctive therapy for DR should be cautious of possible unintended effects.