[The clinical efficacy of glutamine dipeptides on postoperative patients: an updated systematic review of randomized controlled trials from Europe and Asia (1997 - 2005)].

Objective: To examine the effects of parenteral supplementation of glutamine dipeptide on the outcomes of surgical patients.

Methods: The relevant data 1997 to March or May 2005 were retrieved from SCI, Medline, EMBASE, Chinese Cochrane Centre databases. The bibliographies of the retrieved papers and the personal file were searched as well. All the patients in the retrieved papers received parenteral nutrition, whether alanyl-glutamine dipeptide (Ala-Gln) was added was the only difference between the intervention and control groups. Methodological quality assessment was based on the Cochrane Reviewers' Handbook and Jadad's Score Scale. Statistical software RevMan4.2 was used for meta-analysis. The data were treated by intention-to-treat method.

Results: A total of 1074 relevant papers were screened. Thirteen prospective randomized controlled clinical trials (RCTs) from European & Asian studies met the inclusion criteria. Ten RCTs reported 355 cases of infectious complications showed that Ala-Gln administration significantly reduced the prevalence of infectious complications with a pooled relative risk (RR) of 0.42 (95% CI 0.24 - 0.72; P = 0.002). Eight studies with 273 cases reported the postoperative length of stay (LOS) and showed that Ala-Gln significantly reduced the postoperative LOS by 3.25 days (95% CI = -4.87 to -1.62; P = 0.00009). There was no significant effect of Ala-Gln on cost of hospitalization, though there was a trend to reduction (2 studies, pooled n = 52, P = 0.2).

Conclusion: Parenteral Ala-Gln significantly reduces the post-operative infectious morbidity and LOS among surgical patients.