Admission hyperglycemia: Is it a predictor of the outcome of ICU patients?

ABSTRACT

This study was designed to investigate the association between admission random blood glucose [RBG] concentrations and serum levels of interleukin-6 [IL-6] and tumor necrosis factor-Alpha [TNF-Alpha] and is correlation to mortality rate in ICU patients. The study included 80 patients [56 males and 24 females; with mean age of 65.8 +/- 10.5 years] admitted to ICU and receiving mechanical ventilation. Twelve patients were diabetics and 68 patients were non-diabetic. The study also included 10 healthy non-diabetic volunteers as control group. At admission, demographic and clinical information were obtained, scores were calculated the Acute physiology and Chronic Health Evaluation [APACHE II] and the simplified Therapeutic Intervention Scoring System [TISS-28] and blood samples were withdrawn; hyperglycemia was considered if RBG level was >200mg/di. All patients had significantly [p<0.05] higher RBG levels in comparison to control; 47 patients [58.7%] were normoglycemic while 33 patients [41.3%] were hyperglycemic with significantly [p<0.05] higher RBG levels. All patients had significantly [p<0.05] higher serum IL-6 and TNF-Alpha in comparison to control levels and hyperglycemic patients had a significantly [p<0.05] higher levels compared to normoglycemic patients with a positive significant correlation between RBG levels and serum level of IL-6, [r=0.716, p<0.001] and serum levels of TNF-Alpha, [r=0.559, p<0.001]. Total morality was 22.5% [12.8% in normoglycemics and 36.4% in hyperglycemic patients]. Non-survivors had a significantly [p<0.05] increased RBG and serum IL-6 levels compared to survivors with a negative significant correlation between survival and RBG levels, [r=-0.312, p=0.005] and serum level of IL -6, [r=-0.294, p=0.008]. Using multivariate regression analysis revealed that at admission RBG level, [BETA=0.322, p=0.003], followed by at admission serum level of IL-6, [BETA=0.228, p=0.033] and lastly patients' age, [BETA=0.202, p=0.041] are the factors that most significantly affect survival rate. Using the receiver operating characteristic [ROC] curve analysis judged by the are under the curve [AUC] revealed that at admission RBG level, [AUC=0.470] had near equal sensitivity and specificity as a predictor for survival, while serum level of IL-6, [AUC=0.349] and patients' age, [AUC=0.294], both factors showed higher sensitivity and were less specific predictors of survival. It could be concluded that elevated random glucose concentrations estimated at admission to ICU are associated with increased intensive care unit mortality rate especially in non-diabetic patients and is statistically correlated with disturbed immune functions in the form of increased production of pro-inflammatory cytokines