Relationship between interleukin-6 and ammonia in patients with minimal hepatic encephalopathy due to liver cirrhosis.
OBJECTIVE
Previous studies have shown significantly elevated levels of interleukin (IL)-6 in cirrhotic patients with minimal hepatic encephalopathy (MHE), but the relationship between circulating levels of IL-6 and ammonia is unclear. The aim of this study is to investigate the relationship between both variables in cirrhotic patients with MHE.


METHODS
Psychometric tests including number connection test part A (NCT-A) and digit symbol test (DST) were performed to diagnose MHE in 85 cirrhotic patients. Simultaneously, circulating levels of IL-6 and ammonia were measured.


RESULTS
Thirty-two (37.6%) cirrhotic patients were diagnosed with MHE. IL-6 and ammonia were the independent predictors of the presence of MHE (P < 0.05 for both variables). Circulating levels of IL-6 and ammonia correlated with the severity of MHE represented by results of NCT-A (r = 0.56, P < 0.05 and r = 0.39, P < 0.05, respectively) and DST (r = -0.48, P < 0.05 and r = -0.47, P < 0.05, respectively). Moreover, there was a significant correlation between circulating levels of IL-6 and those of ammonia in patients with MHE (r = 0.61, P < 0.05), and a positive additive interaction was found between IL-6 and ammonia on the presence of MHE, with a significant synergy index of 1.51 (95% confidence interval = 1.12-3.46).


CONCLUSIONS
The present study demonstrates a significant correlation and a positive additive interaction between IL-6 and ammonia in cirrhotic patients with MHE, suggesting that IL-6 may have a potential synergistic relationship with ammonia in the induction of MHE.
Graduate School, Tianjin Medical University             Graduate School, Tianjin University of Traditional Chinese Medicine             Tianjin Liver Disease Institute, Tianjin Infectious Disease Hospital, Tianjin, China.
Ming
M
Luo
Lei
L
Li
Er-Na
EN
Yang
Wu-Kui
WK
Cao