Zinc deficiency predicts overt hepatic encephalopathy and mortality in liver cirrhosis patients with minimal hepatic encephalopathy.

AIM: Minimal hepatic encephalopathy (MHE) is associated with poor outcomes and the development of overt hepatic encephalopathy (OHE) in patients with liver cirrhosis (LC). Zinc plays a key role in the detoxification of ammonia, a risk factor of hepatic encephalopathy. This study aimed to investigate whether zinc deficiency predicts OHE occurrence and mortality in LC patients with MHE.

METHOD: This retrospective study included 100 LC patients with MHE. MHE was diagnosed using a computer-aided neuropsychiatric test. Predictors associated with the development of OHE were analyzed using the Fine-Gray competing risk regression model. Cox proportional hazards regression analysis was carried out to evaluate the risk factors of mortality. Survival rates were analyzed using the Kaplan-Meier method and log-rank test.

RESULTS: Of the 100 LC patients with MHE, 41% had zinc deficiency (<60 μg/dl). Zinc deficiency was observed more frequently in the patients with reduced liver function reserve. During the median follow-up period of 9.9 months, 16% of the patients with MHE developed OHE. The patients with zinc deficiency had a higher risk of OHE than those without zinc deficiency (p = 0.03). Zinc deficiency was also associated with poor survival (p = 0.004). Multivariate analyses showed that zinc predicts the development of OHE (subdistribution hazard ratio [HR], 0.95; 95% confidence interval [CI], 0.92-0.99; p = 0.008) and mortality (HR, 0.96; 95% CI, 0.93-0.99; p = 0.02), independently of liver function reserves.

CONCLUSION: Zinc deficiency is likely to be a predictor of both OHE development and mortality in LC patients with MHE.