Mortality prediction of hospitalised type 2 diabetic foot ulcers using Wagner classification in Kaifeng, China: a retrospective cohort study

Background: To summarize the clinical characteristics of inpatients with type 2 diabetic foot ulcers (T2DFU) in a grade 3A hospital in China and observe the prediction effects of Wagner grades for the premature death. Methods 309 Han Chinese inpatients who were diagnosed as T2DFU between September 2009 and November 2019 in a grade 3A hospital in Kaifeng, China. The patients were divided into six subgroups according to Wagner classification. The sociodemographic variables, clinical variables and mortality rate among the six subgroups were compared. Adjusted Cox proportional hazard regression models were conducted to estimate hazard ratios (HR) and 95% confidence interval (95% CI) for the six Wagner grade subgroups. Results Of the 309 patients,in comparison with Wagner grade 0, grade 4 and grade 5 showed a significantly higher cumulative mortality, respectively. In the unadjusted regression model of Wagner grades, the HR [95% CI] for Grade 1 ~ 5 subgroups were 0.86 [0.46–1.61], 0.97 [0.54–1.74], 1.42 [0.78–2.58], 2.20 [1.29–3.75], and 5.39 [2.77–10.51] with grade 0 subgroup as reference (P < 0.001); In a multiple regression model adjusted with age, cardiovascular diseases, peripheral neuropathy, and diabetic nephropathy, the HR [95% CI] for Grade 1 ~ 5 subgroups were 0.95 [0.51–1.77], 1.04 [0.57–1.89], 1.56 [0.86–2.86], 2.27 [1.33–3.89], and 6.39 [3.24–12.61] with grade 0 subgroup as reference (P < 0.001). Conclusions Mortality rate of T2DFU patients increased with Wagner grades, mainly from grade 4 through grade 5 in comparison with grade zero in the present study.