Validation and application of the 2019 International Working Group on the Diabetic Foot risk stratification for...

The purpose of the present study was to evaluate the validation and application of the 2019 International Working Group on the Diabetic Foot (IWGDF) risk stratification system among Chinese patients with diabetes.

A retrospective cohort study was carried out with 254 patients with diabetes, but without an active diabetic foot (DF) ulcer. Patients hospitalized from January to May 2017 were enrolled, and the follow-up period was from January to May 2020. Patients were stratified into four risk groups based on the 2019 IWGDF risk stratification system.

Of the 254 patients, four of 31 patients at risk 1 were diagnosed with DF within 3 years, whereas 12 of 26 patients at risk 2 and 16 of 20 patients at risk 3 developed DF. The area under the curve was 0.919 (P < 0.01, 95% confidence interval 0.893-0.945). Because DF risk 2 and greater (risk 2 + risk 3) was the optimal cut-off point, we simplified the risk stratification system by using two tiers, namely, low risk (risk 0 + 1) and high risk (risk 2 + 3). For the simplified risk stratification system, the sensitivity, specificity, positive likelihood ratio, percent agreement, positive predictive value and negative predictive value were 87.5%, 91.8%, 10.607, 91.3%, 60.8% and 98.1%, respectively. The χ² -test showed that the odds ratio of the high-risk group (risk 2 + 3) was 29.33-fold that of the low-risk group (risk 0 + 1).

The 2019 IWGDF risk stratification system showed high validity and primary screening value in Chinese patients with diabetes. Thus, a simplified, two-tiered IWGDF stratification might be more efficient and cost-effective for predicting DF ulcers.