JWC · 2024
Percentage area reduction at week 4 as a prognostic indicator of complete healing in patients treated with standard of care: a post hoc analysis
Serena, T., Yaakov, S., Yaakov, R., King, E., & Driver, V.R.
Journal of Wound Care, 2024 (MA Healthcare)
In brief
This post hoc analysis of the standard-of-care arm of the multicenter Natrox Topical Oxygen Wound Treatment trial evaluated whether wound area reduction at Week 4 could predict complete healing by Week 12 in patients with hard-to-heal diabetic foot ulcers. Among patients whose wounds achieved more than 50% area reduction at Week 4, 65.4% (17/26) achieved complete closure by Week 12. Week-4 area reduction demonstrated strong ability to distinguish wounds likely to heal from those unlikely to heal (area under the receiver operating characteristic curve 0.92; p<0.001). The authors conclude that the results are consistent with earlier studies and support four-week percentage area reduction as a prognostic indicator.
SerenaGroup conducted the topical oxygen trial on which this analysis is based.
Plain-language summary by SerenaGroup. See the full text for complete methods and results.
Abstract
Early indicators of healing provide valuable information on the potential benefit of treatment. In patients with hard-to-heal (chronic) diabetic foot ulcers (DFUs), timely intervention is critical. Ulcers that fail to show measurable progress within four weeks of treatment are considered recalcitrant. These ulcers increase the risk of soft tissue infection, osteomyelitis and lower extremity amputation. A prognostic indicator or surrogate marker allows for rapid evaluation of treatment efficacy and safety. An inverse correlation between a percentage area reduction (PAR) of ≤50% at week 4 and complete healing by week 12 has been previously established; however, the data were derived from a standard of care (SoC) arm of clinical trials that are over a decade old. In this post hoc analysis, data from a large multicentre prospective randomised controlled trial were reviewed to assess PAR at week 4 as a prognostic indicator in patients treated with SoC. Overall, 65.4% (17/26) of patients with PAR >50% at week 4 achieved complete closure at week 12. The receiver operating characteristic (ROC) curve for area reduction by week 4 showed strong discrimination for predicting non-healing (area under the ROC curve: 0.92; p<0.001; positive predictive value: 70.6%; negative predictive value: 87.2%). These findings are consistent with previous studies and support the use of four-week PAR as a prognostic indicator.
Related in Clinical Guidelines and Wound Care Practices
