Energy expenditure and substrate metabolism in ethanol-induced liver cirrhosis

Abstract
Energy expenditure and substrate metabolism were investigated in 10 patients with alcoholic liver cirrhosis (EtOH-Ci) and 10 healthy controls (C). Resting metabolic rate (RMR) varied from 1,269 to 2,467 kcal/day in C and from 1,228 to 2,098 kcal/day in EtOH-Ci. RMR was significantly related to fat-free mass (FFM) in both groups, but EtOH-Ci decreased FFM and increased RMR when expressed per kilogram FFM (+33%). Glucose intolerance, hyperinsulinemia, and a decreased C-peptide-to-insulin ratio were observed in EtOH-Ci after a test meal. Concomitantly, nonoxidative glucose metabolism was reduced in association with normal increases in glucose oxidation. EtOH-Ci reduced insulin sensitivity (-59%) and maximal insulin-dependent glucose disposal (-40%) during a sequential two-step glucose clamp protocol (phase 1: 1 mU.kg body wt-1.min-1 insulin infusion rate + euglycemia; phase 2: 4 mU.kg body wt-1.min-1 insulin infusion rate + 165 mg/dl plasma glucose concentration). This was explained by reduced glucose storage (-99%, -51%) in association with normal responses in glucose oxidation rate, plasma lactate concentration, lipid oxidation rate, and rate of lipogenesis. Defective glucose storage was independent of reduced FFM. EtOH-Ci increased glucose-induced thermogenesis by 57%. We conclude that increased resting metabolic rate, enhanced thermogenesis, defective glucose storage, and normal glucose oxidation together result in increased energy needs and favor negative energy balance in patients with alcoholic cirrhosis.