High Burden of Diabetic Retinopathy in Individuals with Diabetic Foot Ulcers: A Prospective Comparative Study

Abstract

Purpose

Diabetic foot ulcer (DFU) and diabetic retinopathy (DR) are severe complications of diabetes mellitus reflecting advanced vascular injury. While DR has been extensively studied as a predictor of DFU, data on the burden and determinants of DR among individuals with DFUs remain limited. This study aimed to evaluate the prevalence, severity, and clinical correlates of DR in individuals with DFUs.

Methods

This observational study included 85 individuals with DFUs and 81 individuals with type 2 diabetes mellitus without DFUs. All participants underwent comprehensive ophthalmologic examination for DR classification. Demographic characteristics, comorbidities, and laboratory parameters were recorded. Unadjusted and adjusted odds ratios (UORs and AORs) with 95% confidence intervals were calculated.

Results

DR was significantly more prevalent in individuals with DFUs than in controls (85.9% vs 51.9%; UOR 5.65, 95% CI 2.67-11.96; p < .001). Proliferative DR was approximately threefold more frequent in the DFU group (33.0% vs 11.1%; UOR 3.93, 95% CI 1.72-8.99; p = .002). Higher Wagner ulcer grades were associated with increased DR prevalence (p = .005). In multivariate analysis, longer duration of diabetes and proteinuria remained independently associated with DR, while HbA1c showed a modest independent association. Among DFU patients, DR was also associated with hypertension, proteinuria, and coronary artery disease.

Conclusion

Individuals with DFUs carry a markedly increased burden of DR, particularly proliferative disease, indicating advanced systemic microvascular involvement. DFU should be regarded as a clinical red flag for severe retinopathy, warranting prompt and comprehensive ophthalmologic screening alongside integrated renal and cardiovascular assessment.