Efficacy of glutamine-enriched enteral feeding formulae in critically ill patients: a systematic review and meta-analysis of randomized controlled trials.

Critically ill patients usually suffer from catabolic stress that could lead to malnutrition and nutritional support therefore is essential to maintain lean body mass, improve metabolic and immune response and decrease rate of mortality and comorbidity in these patients. This meta-analysis was aimed to evaluate effect of glutamineenriched enteral nutrition in critically ill patients. In order to obtain randomized clinical trial studies (RCTs), international databases including MEDLINE and Google scholar and also electronic resources in Iran, including IRAN MEDEX, IRAN DOC, SID, Magiran were systematically searched without language and publication restriction before December 2014. The final included number of studies for meta-analysis was 10. The methodological quality of eligible studies was assessed by four investigators using the Jadad 5-point scale, a scale containing three items describing randomization, blinding and fate of participants. We analyzed data from the included studies using STATA version 12.0, and calculated a pooled odds ratio for dichotomous data and mean differences for continuous data with 95% confidence intervals (CIs). There was no significant difference in mortality in elevated pooled odds ratios (p-value=0.070). A funnel plot was drawn for evaluation of publication bias, but none was found. The fixed effect model shows significant reduction in gut permeability in who received enteral feeding enriched with glutamine (-0.84, 95% CI=-1.25 to -0.44), moreover the funnel plot did not show publication bias. Based on the available data, our meta-analysis showed that enteral glutamine (Gln) supplementation increased mortality rate, though non-significantly, but decreased gut permeability significantly.