GLP-1 Levels Predict Mortality in Patients with Critical Illness as Well as End-Stage Renal Disease

Background Glucagon-like peptide 1 (GLP-1) is an incretin hormone, which stimulates glucose-dependent insulin secretion from the pancreas and holds immune-regulatory properties. A marked increase of GLP-1 has been found in critically ill patients. This study was performed to elucidate the underlying mechanism and evaluate its prognostic value. Methods GLP-1 plasma levels were determined in 3 different patient cohorts: 1) critically ill patients admitted to our intensive care unit (n = 215); 2) patients with chronic kidney disease on hemodialysis (n = 173); and 3) a control group (no kidney disease, no acute inflammation, n = 105). In vitro experiments were performed to evaluate GLP-1 secretion in response to human serum samples from the above-described cohorts. Results Critically ill patients presented with 6.35-fold higher GLP-1 plasma level in comparison with the control group. There was a significant correlation of GLP-1 levels with markers for the severity of inflammation, but also kidney function. Patients with end-stage renal disease displayed 4.46-fold higher GLP-1 concentrations in comparison with the control group. In vitro experiments revealed a strong GLP-1-inducing potential of serum from critically ill patients, while serum from hemodialysis patients only modestly increased GLP-1 secretion. GLP-1 levels independently predicted mortality in critically ill patients and patients with end-stage renal disease. Conclusions Chronic and acute inflammatory processes like sepsis or chronic kidney disease increase circulating GLP-1 levels. This most likely reflects a sum effect of increased GLP-1 secretion and decreased GLP-1 clearance. GLP-1 plasma levels independently predict the outcome of critically ill and end-stage renal disease patients.