Values of glycemic lability index in the prognostic evaluation of critically ill patients in intensive care unit

Abstract

To access the predictive values of glycemic lability index (GLI) as an indicator of glucose variability in the prognosis of critically ill patients. A prospective study of 72 critically ill patients admitted into intensive care unit (ICU) were performed. Capillary glucose was measured on admission and every 2 hrs afterward during the first 24 hrs. GLI, mean amplitude of glycemic excursion (MAGE), largest amplitude of glycemic excursions (LAGE), mean, standard deviation (SD) and coefficient of variability (CV) were calculated respectively. The 30 day mortality was selected as the end-point. Receiver operating curve (ROC) was drawn to explore the association between each indicator of glucose variability and prognosis. The subjects were subsequently divided into 4 subgroups according to the median of mean and GLI. The 30-day mortality was then compared between the subgroups. Thirty-one of 72 patients died with a mortality rate of 43.1%. The area under the curve (AUC) of GLI (0.798 ± 0.051) was superior to that of MAGE (0.785 ± 0.053), LAGE (0.772 ± 0.056), SD (0.761 ± 0.056), CV (0.729 ± 0.059) and mean (0.670 ± 0.065) under the determination of ROC respectively. GLI was significantly correlated with APACHE II (acute physiology and chronic health evaluation II) score assessed during the first 24 hrs after admission (R(2) = 0.787, P < 0.001). With the rise of GLI value, the 30-day mortality also increased gradually. Subgroup analysis demonstrated that the duration of mechanical ventilation, the incidence of multiple organ failure (MOF), the utilization rate of CRRT (continuous renal replacement therapy), the staying length of ICU and the 30 mortality rate was (3.3 ± 4.4) d, 41.6%, 12.5%, (4.6 ± 4.5) d and 16.7% respectively in the low mean +low GLI subgroup. They decreased obviously compared to the low mean +high GLI, high mean +low GLI and high mean +high GLI groups. Therefore the low mean +low GLI subgroup had the best prognosis while the high mean +high GLI subgroup worst. GLI of the first 24 hrs after ICU admission can serve as an indicator of glucose variability. And it is significantly correlated with the patient prognosis.