Effectiveness of glutamine in the management of oral mucositis in cancer patients: a meta-analysis of randomized controlled trials.

Objective The aim of this meta-analysis was to evaluate the effectiveness of glutamine for preventing or treating moderate-to-severe oral mucositis induced by chemotherapy or radiation therapy in patients with cancer. Methods PubMed, Cochrane Library, and Embase were searched for eligible randomized controlled trials (RCTs) up to June 2020. The outcomes analyzed were oral mucositis (at all levels of severity). Data were pooled using the random-effects model and are expressed as risk ratios (RRs) and corresponding 95% confidence intervals (CIs). Heterogeneity was assessed and quantified using I2. Results Sixteen RCTs were included in this review. In this meta-analysis, compared with placebo, glutamine significantly reduced the incidence of grade 3 and 4 oral mucositis induced by chemotherapy or radiation therapy (RR, 0.53; 95% CI, 0.32-0.88). In subgroup analysis, oral glutamine administration (RR, 0.56; 95% CI, 0.34-0.92) and a medium or low daily dose of glutamine (RR, 0.58; 95% CI, 0.44-0.77; RR, 0.53; 95% CI, 0.28-0.94; respectively) decreased risk. Glutamine caused a borderline significant reduction in the risk of grade 3 and 4 oral mucositis induced by radiotherapy (RR, 0.75; 95% CI, 0.58-0.99) and especially in its prevention (RR, 0.51; 95% CI, 0.28-0.94). Conclusions Glutamine significantly reduces the risk of oral mucositis during chemotherapy or radiation therapy. Furthermore, large prospective trials are required to support these findings.