Immunonutrition Is Associated With a Decreased Incidence of Graft-Versus-Host Disease in Bone Marrow Transplant Recipients: A Meta-Analysis
Introduction: Graft-versus-host disease (GVHD) is a serious complication of bone marrow transplantation (BMT), requiring higher doses of glucocorticoids or immunosuppressive therapies and further straining transplant recipients. Immunonutrition, such as vitamins and amino acid supplements, increase immunity and decrease inflammation and oxidative stress. This meta-analysis examines the impact of immunonutrition on the incidence of GVHD and postoperative infections among BMT recipients. Methods: A comprehensive literature search for all published randomized controlled trials was conducted with PubMed, Cochrane Central Registry of Controlled Trials, and Google Scholar (1966–2016). Keywords in the search included variations of terms related to immunonutrition, such as “vitamin,” “glutamine,” and “transplant.” Outcomes included incidence of GVHD and infection. Results: Ten randomized controlled trials involving 681 BMT recipients were analyzed: 332 receiving immunonutrition and 349 receiving standard nutrition. Immunonutrition is correlated with a decreased incidence of GVHD by 19% (relative risk [RR] = 0.810, 95% CI: 0.695–0.945, P = .007). There was no significant difference in the incidence of infections with immunonutrition (RR = 1.016, 95% CI: 0.819–1.261, P = .885). Subgroup analysis of glutamine compared with N-acetylcysteine, selenium, and eicosapentaenoic acid showed no significant difference in the incidence of GVHD or infections (RR = 0.913, 95% CI: 0.732–1.139, P = .419; RR = 0.951, 95% CI: 0.732–1.235; P = .708, respectively). Conclusion: The use of immunonutrition is associated with a reduced risk of GVHD in BMT recipients, potentially as a result of improved immune support and free radical scavenging. Providing immunonutrient supplements is a valuable adjunct in the routine care of BMT recipients, helping to alleviate a common and deadly complication.