417-P: Diabetic Foot Ulcer Amputation Increases the Risk of Severe Renal and Retinal Microvascular Complications—A Korean National Health Information Database Study

Diabetic foot ulcer (DFU) and subsequent amputation represents significant health burden associated with diabetes. It is widely recognized that individuals with diabetic end stage kidney disease (ESKD) and proliferative diabetic retinopathy (PDR) face an elevated risk of limb amputation, but vice versa remains unclear. This study aimed to investigate the incidence rate and quantify the risk of ESKD and PDR in people who experienced DFU amputation. Using the database from National Health Insurance Service in South Korea, we included people with diabetes who received national health screening from 2009 to 2012. DFU amputation was defined using International Classification of Diseases 10^th revision codes (ICD-10). Incident cases of ESKD or PDR were defined as diagnoses occurring at least one year following DFU amputation, as determined by the ICD-10 codes. Cox proportional hazard regression analysis was used to estimate the risk of incident ESKD or PDR after DFU amputation adjusting for covariates. Among 1,447,438 individuals enrolled, 1,512 (0.10%) had received DFU amputation at baseline. The incidence rate (IR) of ESKD was significantly higher in people who received DFU amputation compared to those who did not (14.8 vs 1.6 per 1,000 person-years), and adjusted hazard ratio (HR) was 2.46 (95% CI 2.08-2.91). Similar result was observed for PDR; IR was 24.7 vs 6.5 per 1,000 person-years and adjusted HR was 2.08 (95% CI 1.82-2.38). When we performed subgroup analysis based on major vs minor amputation, subjects who received major amputations had higher risk for ESKD (HR 3.13, 95% CI 2.39-4.11) and PDR (HR 2.39, 95% CI 1.87-3.07) compared with subjects who received minor amputations (ESKD: HR 2.17, 95% CI 1.75-2.69; PDR: HR 1.97, 95% CI 1.68-2.31). In summary, using a national health information database, we found that people who received DFU amputation have significantly increased risk of microvascular complications of ESKD or PDR.