Evaluation of the effects of combination therapy with branched-chain amino acid and zinc supplements on nitrogen metabolism in liver cirrhosis.

Aim: Disorders of protein metabolism in liver cirrhosis can affect prognosis or cause complications. Treatment with branched-chain amino acid (BCAA) and zinc supplements has been shown to be effective against abnormal nitrogen metabolism in liver cirrhosis. There are, however, few studies on the effects of combining these supplements. In this study, the effect of combining BCAA and zinc treatment in cirrhosis was investigated. Methods: Forty patients with liver cirrhosis who had blood albumin levels of 3.5 g/dL or less and blood zinc levels of 70 mu g/dL or less were randomized to receive either BCAA alone or a combination of BCAA and zinc supplements. Blood albumin, the Fischer ratio, and ammonia levels were compared over 5-6 months of treatment. Results: in the combination group, the post/pre treatment change ratio in blood ammonia levels decreased significantly (0.87 +/- 0.26 vs. 1.22 +/- 0.38, P = 0.0033), and the change ratio in the Fischer ratio increased significantly (1.22 +/- 0.29 vs. 1.08 +/- 0.16, P=0.01.65) in comparison with the BCAA monotherapy group. The change ratio in blood albumin levels showed no significant difference between the groups (1.01 +/- 0.07 vs. 1.03 +/- 0.08, P = 0.4646). Conclusions: More improvement in disorders of nitrogen metabolism in liver cirrhosis occurred after administration of BCAA with zinc than after BCAA alone over 5-6 months of treatment. Further investigation is necessary to determine mechanisms of the action and longer-term clinical efficacy.