EC Ophthalmology

Introduction: Diabetes affects 11.6% of South Texans, leading to disabling conditions including diabetic foot ulcers (DFU) and diabetic retinopathy (DR). Peripheral vasculopathy (PV) and diabetic neuropathy (DN) have been reported as independent risk factors for developing DFU. However, the relationship between systemic parameters of DFU (PV and DN) and ocular outcomes of DR (visual acuity) remain unknown. Therefore, we investigated visual outcomes of diabetic patients with DFU alone compared to patients with additional PV or DN in relation to diabetic retinopathy (DR).

Methods: A retrospective review was done on patients visiting a tertiary center in San Antonio that were diagnosed with DFU and underwent ophthalmic and neurovascular examinations within the past 10 years; 144 diabetic eyes were included. The prevalence of DR with DFU with or without concomitant PV or DN was assessed using visual acuity (Log MAR) as the primary endpoint.

Results: The study group of 144 eyes (72 subjects) had an average age of 59.9 and was 54.2% male. At the final visit, proliferative diabetic retinopathy (PDR) was found in 73.4% of the DFU-only group, 75.0% of the DFU-with-PV group, and 73.4% of the DFU-with-DN group. New onset of PDR was noted in 43.3% of DFU-only, 63.3% of DFU-with-PV, and 54.1% of DFU-with-DN during the follow-up period (p > 0.05). Initial average visual acuity, represented by Log MAR, was 0.627 for the DFU-only, 0.491 for DFU-with-PV, and 0.514 for the DFU-with-DN. Final average visual acuity was 0.429 for DFU-only, 0.515 for DFU-with-PV, and 0.593 for DFU-with- DN. With an average follow-up period of 50.7 months, the DFU-only group demonstrated an average Log MAR change of -0.198 compared to +0.024 in the DFU-with-PV group and +0.078 in the DFU-with-DN group (p = 0.036). Furthermore, diabetic patients with DFU were more likely to require panretinal photocoagulation (PRP) during the follow-up period if they experienced concomitant PV (72.9%) compared to DFU alone (60.9%) or with concomitant DN (29.7%, p = 0.0007).

Conclusion: Most patients with DFU experienced a progression of DR to PDR. DFU patients with DN experienced significant declining visual acuity despite necessary treatment for DR. Those with PV were slightly more likely to develop PDR and were significantly more likely to receive PRP treatment. All patients with DFU should undergo timely retinal examinations and management to prevent premature blindness from DR-in particular those with PV and DN.

 Keywords: Diabetic Retinopathy; Peripheral Vasculopathy; Foot Ulcer; Neuropathy; Diabetes; Proliferative Diabetic Retinopathy

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