Abstract Objective To evaluate racial and ethnic disparities in progression from non-proliferative diabetic retinopathy (NPDR) to treatment-warranted diabetic eye disease (TW-DED), and the influence of microvascular diabetic complications, including nephropathy (DN) and foot ulcers (DFU). Methods We conducted a retrospective cohort study using a federated electronic health records network (2005–2025) of adults ≥40 years with type 2 diabetes and NPDR, excluding those with prior TW-DED. Participants were stratified by race/ethnicity (White, Hispanic, Black, Asian, Other) and by DN and/or DFU status. Propensity score matching (1:1) balanced baseline characteristics. The primary outcome was progression to TW-DED, defined as proliferative diabetic retinopathy, macular oedema, vitreous haemorrhage, or need for retinopathy-related treatment, assessed over 10 years. Risk ratios (RR) and hazard ratios (HR) with 95% confidence intervals (CI) were reported. Results Among 130,002 patients with NPDR, Hispanic (RR 1.40, 95% CI 1.32–1.48), Black (RR 1.15, 95% CI 1.10–1.20), and Other (RR 1.13, 95% CI 1.04–1.24) patients demonstrated higher risks of TW-DED progression than White patients. In multivariable analysis, race/ethnicity was no longer significant, whereas DFU (HR 1.08, 95% CI 1.02–1.15) and DN (HR 1.06, 95% CI 1.01–1.12) remained independently associated with TW-DED. Stratified analysis revealed DFU consistently conferred greater risk than DN (Hispanic HR 1.39; Other HR 1.32; Black HR 1.27; White HR 1.22). Conclusion Hispanic, Black, and Other groups had higher risk of TW-DED progression, but differences diminished after comorbidity adjustment. DFU and DN independently predicted progression, with DFU posing greater risk, suggesting microvascular disease burden and management differences may underlie racial differences.
Hong et al. (Mon,) studied this question.