Pharmaconutrition: how has this concept evolved in the last two decades?

Glutamine supplementation in acute pancreatitis: a meta-analysis of randomized controlled trials

BACKGROUND

There is emerging evidence that glutamine supplementation should be considered in patients with acute and critical illness associated with a catabolic response. There are reports of glutamine supplementation in acute pancreatitis but the results of these studies are conflicting. The aim of this study was to systematically review the randomised controlled trials (RCT) of glutamine in patients with acute pancreatitis.

METHODS

The Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, SCOPUS and 3 major Chinese databases were searched. The outcomes studied were mortality, total infectious complications, and length of hospital stay. A random effects model was used for meta-analysis of the outcomes in the included trials. A number of pre-specified subgroup analyses were also conducted. The summary estimates were reported as risk ratio (RR) for categorical variables and mean difference (MD) for continuous variables together with the corresponding 95% confidence interval.

RESULTS

Twelve RCT that enrolled 505 patients with acute pancreatitis were included in the final analysis. Overall, glutamine supplementation resulted in a significantly reduced risk of mortality (RR 0.30; 95% CI, 0.15 to 0.60; P < 0.001) and total infectious complications (RR 0.58; 95% CI, 0.39 to 0.87; P = 0.009) but not length of hospital stay (MD -1.35; 95% CI, -3.25 to 0.56, P = 0.17). In the subgroup analyses, only patients who received parenteral nutrition and those who received glutamine in combination with other immunonutrients demonstrated a statistically significant benefit in terms of all the studied outcomes.

CONCLUSIONS

This meta-analysis demonstrates a clear advantage for glutamine supplementation in patients with acute pancreatitis who receive total parenteral nutrition. Patients with acute pancreatitis who receive enteral nutrition do not require glutamine supplementation. Further studies are warranted to determine whether patients who receive combined enteral and parenteral nutrition need glutamine supplementation.

Effect of parenteral selenium supplementation in critically ill patients: a systematic review and meta-analysis

BACKGROUND

It is currently unclear whether parenteral selenium supplementation should be recommended in the management of critically ill patients. Here we conducted a systematic review and meta-analysis to assess the efficacy of parenteral selenium supplementation on clinical outcomes.

METHODS/PRINCIPAL FINDINGS

Randomized trials investigating parenteral selenium supplementation administered in addition to standard of care to critically ill patients were included. CENTRAL, Medline, EMBASE, the Science Citation Index, and CINAHL were searched with complementary manual searches. The primary outcome was all-cause mortality. Trials published in any language were included. Two authors independently extracted data and assessed trial quality. A third author was consulted to resolve disagreements and for quality assurance. Twelve trials were included and meta-analysis was performed on nine trials that recruited critically ill septic patients. These comprised 965 participants in total. Of these, 148 patients (30.7%) in the treatment groups, and 180 patients (37.3%) in control groups died. Parenteral selenium treatment significantly reduced all-cause mortality in critically ill patients with sepsis (relative risk [RR] 0.83, 95% CI 0.70-0.99, p = 0.04, I(2) = 0%). Subgroup analyses demonstrated that the administration schedule employing longer duration (RR 0.77, 95% CI 0.63-0.94, p = 0.01, I(2) = 0%), loading boluses (RR 0.73, 95% CI 0.58-0.94, p = 0.01, I(2) = 0%) or high-dose selenium treatment (RR 0.77, 95% CI 0.61-0.99, p = 0.04, I(2) = 0%) might be associated with a lower mortality risk. There was no evidence of adverse events.

CONCLUSIONS/SIGNIFICANCE

Parenteral selenium supplementation reduces risk of mortality among critically ill patients with sepsis. Owing to the varied methodological quality of the studies, future high-quality randomized trials that directly focus on the effect of adequate-duration of parenteral selenium supplementation for severe septic patients are needed to confirm our results. Clinicians should consider these findings when treating this high-risk population.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO 2011; CRD42011001768.