Topical oxygen therapy for diabetes-related foot ulcers: A systematic review and meta-analysis

Topical oxygen therapy (TOT) has been suggested as a treatment for diabetes-related foot ulcer (DFU) but no prior meta-analyses of randomised clinical trials (RCT) have been reported. This systematic review and meta-analysis examined the randomised evidence for the benefit of TOT in healing DFU.

Publicly available databases were searched for RCTs investigating the effect of TOT on wound healing in participants with a DFU. The primary outcome was ulcer healing defined as full epithelialisation. Meta-analyses were performed using random effect models and reported as risk ratios (RR) and 95% confidence intervals (CI). Study quality and publication bias were assessed using a modified version of the Cochrane Collaboration's tool and funnel plots, respectively.

Six RCTs involving 530 participants with a DFU testing TOT were included. Meta-analysis suggested that TOT significantly increased the likelihood of ulcer healing compared to controls (Risk ratio [RR] 1.94; 95% CI 1.19, 3.17; I²  = 57%; NNT = 5.33) and findings were robust in sensitivity analyses. Risk of bias was high, moderate and low in two, one and three studies, respectively. Analysis of the three trials judged to be at low risk of bias suggested that TOT increased the likelihood of ulcer healing compared to controls (RR 2.37; 95% CI 1.52, 3.68; I²  = 0%). Funnel plots suggested the possibility of publication bias. Data on amputation were too limited for meta-analysis.

This meta-analysis suggests that TOT improves the likelihood of DFU healing; however, its effect on amputation and cost-effectiveness are unclear.