Nocturnal branched-chain amino acid administration improves protein metabolism in patients with liver cirrhosis: comparison with daytime administration.

Background: In an attempt to optimize oral branched-chain amino acid (BCAA) administration to improve serum albumin in cirrhotic patients, we compared the effects of nocturnal and daytime BCAA administration on protein metabolism in cirrhotic patients.

Methods: Twelve cirrhotic patients were enrolled in a short-term study. Patients were administered either conventional daytime BCAA granule or nocturnal BCAA for a week, and metabolic analyses were performed, followed by a crossover study in the next week. Another 12 patients, who showed no improvement of serum albumin level with previous daytime BCAA administration, were randomly assigned to either a nocturnal or a daytime BCAA administration group in a long-term study.

Results: Low Fischer's ratio, reduced respiratory quotient, and low serum albumin were observed at entry in cirrhotic patients. Whereas daytime BCAA administration improved nitrogen balance and Fischer's ratio, these 2 were further significantly improved after nocturnal BCAA administration. There were no changes in parameters of energy metabolism throughout the study. In the 3-month follow-up, a significant increase in serum albumin was observed in patients administered nocturnal BCAA but not in those administered daytime BCAA.

Conclusions: Nocturnal BCAA administration improved serum albumin in cirrhotic patients who showed no improvement in serum albumin level with daytime BCAA administration. This effect could be partly caused by the improved protein sparing with this administration method.