Resting Energy Expenditure and Substrate Metabolism in Patients With Acute-on-chronic Hepatitis B Liver Failure

Goals: This study was designed to characterize the energy metabolism in the patients with acute-on-chronic liver failure (ACLF). Background: Protein-energy malnutrition usually occurs in the patients with chronic liver disease and is exacerbated during the progression of liver failure. Unfortunately, there is limited study to fully elucidate the energy metabolism in the patients with ACLF. Study: A retrospective cohort was designed with a total of 282 patients (100 patients with ACLF, 100 with liver cirrhosis, and 82 with chronic hepatitis B). Resting energy expenditure and the oxidation rates of glucose, lipid, and protein were assessed by indirect heat measurement using the critical care monitor and desktop analysis system, nutritive metabolic investigation system. Survival rate was estimated with the Kaplan-Meier method. Results: There was no significant difference in resting energy expenditure among the patients with ACLF, the liver cirrhosis, and the chronic hepatitis (1402.05 +/- 480.07 kcal/d in patients with ACLF, 1274.27 +/- 316.36 kcal/d in patients with liver cirrhosis, and 1396.77 +/- 384.80 kcal/d in patients with chronic hepatitis). Respiratory quotient (RQ) was significantly lower in the patients with ACLF than those in the liver cirrhosis and the chronic hepatitis B (P=0.000). In patients with ACLF, RQ of the nonsurvival group was significantly lower than the survival group (P=0.000). It is identified from receiver operating characteristic curve analysis that a RQ cutoff value of 0.83 (area under the receiver operating characteristic curve, 0.760) is favorable to predict good prognosis in patients with liver failure, which has a sensitivity of 73.68%, a specificity of 74.42%, and positive predictive value of 79.2% and negative predictive value of 68.1%. Conclusions: In patients with ACLF, RQ was significantly lower in the nonsurvival group than the survival group, thus suggesting that RQ may be used as an indicator of prognosis of liver failure.