Exogenous Glucagon-Like Peptide-1 for Hyperglycemia in Critically III Patients

OBJECTIVE: To review literature evaluating the safety and efficacy of exogenous glucagon-like peptide-1 (GLP-1) for hyperglycemia in critically ill patients. DATA SOURCES: PubMed was queried (inception to September 3, 2011), using the search term glucagon-like peptide-1. The search was limited to studies published in English and conducted in humans. Regular and late-breaking abstracts from the American Diabetes Association Scientific Sessions in 2009 and 2010 were also searched using the same search term. STUDY SELECTION AND DATA EXTRACTION: All abstracts were screened for eligibility, which consisted of studies reporting the effects of intravenous GLP-1 administration on glycemic control in critically ill patients. Data extracted from eligible trials included study and population characteristics, measures of glycemic efficacy, and safety. DATA SYNTHESIS: Our search resulted in the identification of 2105 potentially relevant articles; of those, 7 were reviewed. All included publications evaluated the use of intravenous GLP-1 (1.2-3.6 pmol/kg/min) compared with insulin or placebo infused for 4.5-72 hours in critically ill patients. The majority (n = 4) of studies included only patients from a surgical intensive care setting, and 71% (n = 5) of trials included those with a history of diabetes. Relative to insulin or placebo, GLP-1 therapy effectively lowered blood glucose concentrations in all trials. Out of 81 total study participants receiving GLP-1, only 4 had documented hypoglycemia (<60 mg/dL), 4 reported nausea, and 2 experienced vomiting. No other serious adverse events were reported. CONCLUSIONS: All trials reviewed suggest that GLP-1 may be a promising agent for the management of hyperglycemia in critically ill patients, regardless of diabetes status. Additional studies in more heterogeneous intensive care settings comparing GLP-1 with insulin, the current standard of care, are necessary. These studies should evaluate long-term safety and effectiveness of GLP-1 therapy on morbidity and mortality outcomes in critically ill populations.