Systematic review with meta-analysis: effectiveness of hyperbaric oxygenation therapy for ulcerative colitis

BACKGROUND AND AIMS: Hyperbaric oxygenation therapy has been used in the treatment of ulcerative colitis in the past few years. However, its efficacy still remains unclear. The aim of the study was to investigate the efficacy of hyperbaric oxygen combination therapy in patients with ulcerative colitis. METHODS: We conducted a comprehensive study search up to September 2020, from the online databases Embase, PubMed, Cochrane Library, China National Knowledge Infrastructure, WanFang and VIP. RESULTS: Thirteen studies comprising 780 patients were included. We found that compared with conventional therapy, hyperbaric oxygen combination therapy was superior in reaching clinical remission [risk ratio (RR)=1.62; 95% confidence interval (CI) 1.42 to 1.84; p < 0.001] and clinical response (RR=1.29; 95% CI 1.21 to 1.38; p < 0.001), with lower disease activity scores [standard mean difference (SMD)= −1.19; 95%CI −1.74 to −0.65; p < 0.001]. An obvious reduction of serum levels of tumor necrosis factor-α (SMD= −1.96; 95%CI −2.50 to −1.41; p < 0.001) and interleukin (IL)-6 (SMD= −2.49; 95% CI −2.84 to −2.15; p < 0.001), and elevation of IL-10 level (SMD=2.40; 95% CI 0.68 to 4.12; p = 0.006) were also observed. CONCLUSION: Hyperbaric oxygen combination therapy was effective in patients with ulcerative colitis, and has potential as a complementary method for its treatment.