Differentiating diabetic foot ulcers that are unlikely to heal by 12 weeks following achieving 50% percent area reduction at 4 weeks

This retrospective analysis included intent-to-treat control patient data from two published, randomised, diabetic foot ulcer (DFU) trials in an effort to differentiate ulcers that are unlikely to heal by 12 weeks despite early healing progress [>= 50% percent area reduction (PAR) at 4 weeks]. Predicted and actual wound area trajectories in DFUs that achieved early healing progress were analysed from weeks 5 to 12 and compared for ulcers that did and did not heal at 12 weeks. In 120 patients who achieved >= 50% PAR by week 4, 62 (52%) failed to heal by 12 weeks. Deviations from the predicted healing course were evident by 6 weeks for non healing ulcers. A 2-week delay in healing significantly lowered healing rates (P = 0.001). For DFUs with >= 50% PAR at 4 weeks, those achieving >= 90% versus <90% PAR at 8 weeks had a 2.7-fold higher healing rate at 12 weeks (P = 0.001). A PAR of <90% at 8 weeks provided a negative predictive value for DFU healing at 12 weeks of 82%. For ulcers that fail to progress or worsen from weeks 4 to 6, and those that fail to achieve 90% PAR at 8 weeks, reevaluation of the wound and its treatment is recommended.