Ulcer-free survival days and ulcer healing in patients with diabetic foot ulcers: A prospective cohort study

Healing rates may not give a complete indication of the effectiveness and management of diabetic foot ulcers because of high recurrence rates. The most important outcome for patients is remaining ulcer-free; however, this has hardly been investigated. The aim of our study was to prospectively investigate ulcer-free survival days and ulcer healing in patients with diabetic foot ulcers. This was a prospective cohort study of all referrals to our diabetic foot expertise centre from December 2014 to April 2017. Outcomes were determined after a minimum follow-up period of 12 months. Primary outcomes were ulcer-free survival days and 12-month healing percentages. Predictors for ulcer-free survival days and healing were investigated in multivariate analyses. A total of 158 patients were included. Median ulcer-free survival days in the healed group were 233 days (interquartile range [IQR] 121-312) and 131 days (IQR 0-298) in the overall population. The healing rate at 12-month follow up was 67% (106/158), and the recurrence rate was 31% (33/106). Independent predictors of ulcer-free survival days were duration of diabetes, peripheral artery disease (PAD), cardiovascular disease, end-stage renal disease (ESRD), and infection. Ulcer-free survival days are related to PAD and cardiovascular disease, and ulcer-free survival days should be the main outcome when comparing the effectiveness of management and prevention of the diabetic foot ulcers.