Prognostic significance of minimal hepatic encephalopathy in patients with liver cirrhosis in Japan: A propensity score-matching analysis

Background and Aim Minimal hepatic encephalopathy (MHE) represents the mildest form of the hepatic encephalopathy spectrum. This study aimed to clarify the prognostic significance of MHE in cirrhotic patients. Methods This retrospective study evaluated 357 consecutive patients with liver cirrhosis. MHE was diagnosed using a neuropsychiatric test. A propensity score-matching analysis was employed to adjust significant differences in the baseline characteristics between patients with and without MHE. Results Of 269 eligible patients, 56 patients (21%) were diagnosed as having MHE. The Child-Pugh score, model for end-stage liver disease score, and serum ammonia levels were significantly increased, while serum albumin levels were reduced in patients with MHE. By contrast, no significant difference was found between the two groups in matched patients. During the median follow-up period of 13.4 months, 67 patients (24.9%) died. Overall survival rates were significantly lower in patients with MHE (median, 25.4 vs 48.8 months; P < 0.001). Multivariate analysis revealed that male sex (hazard ratio [HR], 1.78; 95% confidence interval [CI], 1.03-3.18; P = 0.038), stage III/IV hepatocellular carcinoma (HR, 6.32; 95% CI, 3.30-12.79; P < 0.001), the Child-Pugh score (HR, 1.35; 95% CI, 1.12-1.62; P = 0.002), and MHE (HR, 1.92; 95% CI, 1.09-3.29; P = 0.024) were independently associated with mortality in all patients as well as in matched patients. Conclusion Minimal hepatic encephalopathy is associated with an increased risk of mortality in patients with liver cirrhosis, independent of hepatocellular carcinoma stage or Child-Pugh score.