Objective: To evaluate correct correlation between an intermediate rate of wound reduction (40% wound area reduction after 4-weeks treatment) and complete healing at 24 weeks in patients with a venous leg ulcer (VLU).
Method: A retrospective follow-up study of patients completing a multicenter randomised controlled trial (RCT) comparing the number of patients achieving at least 40% healing of their VLU within 4-weeks of treatment with either dehydrated human amnion/chorion membrane (dHACM) allograft or multilayer compression only was conducted. Outcomes assessed were rates of complete healing within 24 weeks of enrolment and days to healing. Data were divided into two groups based on status at RCT completion (healed at least 40% yes or no). Correct correlation with status at 4 weeks and complete healing within 24 weeks was determined. Clinical characteristics were also compared for patients with and without correct correlation between 4-week and 24-week status.
Results: We identified 55 patients at 5 study sites. Some 47 without complete healing during the initial study were eligible. As three patients were lost to follow-up we evaluated 44 records. Of these, 20 (45.4%) had reduced wound size of ≥40% and 24 (55%) had <40% reduction during the initial study. Complete healing occurred in 16/20 (80%) of the ≥40% group at a mean of 46 days, p=0.0027 and 8/24 (33.3%) of the <40% group at a mean of 103.6 days, p=0.0023. Overall, correct correlation of status at 4 weeks and ultimate healing status of VLU occurred in 32/44 patients (73%).
Conclusion: These results confirm that the intermediate outcome used in our initial study is a viable predictor of ultimate VLU healing.
Keywords: amniotic membrane; healing rate; intermediate outcomes; venous leg ulcers.