The role of antioxidants and zinc in minimal hepatic encephalopathy: a randomized trial

Therap Adv Gastroenterol. 2016 Sep;9(5):684-91. doi: 10.1177/1756283X16645049. Epub 2016 May 1.


Background: Minimal hepatic encephalopathy (MHE) has a far-reaching impact on quality and function ability in daily life and may progress to overt hepatic encephalopathy. There is a synergistic effect between systemic oxidative stress and ammonia that is implicated in the pathogenesis of hepatic encephalopathy. The aim of this study is to investigate the effectiveness of oral supplementation of antioxidants and zinc gluconate on MHE versus lactulose.

Methods: Our study included 58 patients with cirrhosis diagnosed as having MHE by neuropsychometric tests, including number connection test part A (NCT-A), digit symbol test (DST) and block design tests (BDTs). Patients were randomized to receive 175 mg zinc gluconate, 50,000 IU vitamin A, 500 mg vitamin C and 100 mg vitamin E once daily plus lactulose, dose 30-60 ml/day for 3 months [group A (n = 31)] or initiated and maintained on lactulose dose 30-60 ml/day for 3 months [group B (n = 27)]. Neuropsychometric tests and laboratory investigations were repeated after 3 months of therapy.

Results: Compared with the baseline neuropsychometric tests, a significant improvement was reported in patients with MHE after 3 months of antioxidant and zinc therapy (group A) versus patients with lactulose therapy (group B) (NCT-A, p <0.001; DST, p = 0.006; BDT, p < 0.001). Antioxidant and zinc supplementation significantly decreased arterial ammonia level, alanine aminotransferase (ALT), aspartate aminotransferase (AST) (p < 0.001) and improved Child-Pugh score in MHE after 3 months of therapy (p= 0.024).

Conclusion: Antioxidant and zinc supplementation can improve MHE in patients with liver cirrhosis.

Keywords: antioxidants; minimal hepatic encephalopathy; zinc.