Clinical Performance of the IWGDF Risk Stratification System for Diabetic Foot Ulceration: A Gender-Disaggregated Study of 713 Patients

INTRODUCTION: Diabetic foot ulceration (DFU) is a major complication of diabetes and is a leading cause of lower-extremity amputation. This study evaluated the cross-sectional discriminative performance of the International Working Group on the Diabetic Foot (IWGDF) risk classification for prevalent active DFU, described gender-disaggregated ulcer prevalence, and identified factors independently associated with moderate/high IWGDF risk in a specialist diabetes center. METHODS: In this retrospective cross-sectional study, 713 adults with diabetes mellitus who attended the diabetic foot service of a university diabetes center were classified according to the IWGDF risk system. The prevalence of active DFU was compared across risk categories using the Cochran-Armitage trend test. Multivariable logistic regression was used to identify factors associated with moderate/high IWGDF risk and active DFU. RESULTS: Active DFU was present in 21 patients (2.9%), with no significant difference between men (3.8%) and women (2.1%). Overall, 17.3% of the patients were classified as having moderate or high risk. Ulcer prevalence increased progressively across the IWGDF categories, from 0.0% in the very-low-risk group to 38.5% in the high-risk group (p < 0.001). The IWGDF classification showed excellent cross-sectional discrimination for prevalent active DFU (c-statistic 0.938), with 90.5% sensitivity and 99.7% negative predictive value at the moderate/high-risk threshold. Older age and higher glycated hemoglobin (HbA1c) levels were independently associated with moderate/high IWGDF risk, whereas gender was not. CONCLUSION: The IWGDF classification showed excellent cross-sectional discrimination for prevalent active DFU. Older age and poorer glycemic control, but not gender, were independently associated with moderate/high IWGDF risk. These findings support routine IWGDF-guided risk stratification in specialist diabetes care, although prospective studies are required to establish its performance in predicting future ulceration.