Minimal hepatic encephalopathy is associated with a higher risk of overt hepatic encephalopathy and poorer survival

Background and aims: Minimal hepatic encephalopathy (MHE) is a frequent complication in patients with liver cirrhosis. Its impact on predicting the development of overt hepatic encephalopathy (OHE) and survival has not been studied in large multicenter studies. 

Methods: Data from patients recruited at eight centers across Europe and the United States were analyzed. MHE was detected using the psychometric hepatic encephalopathy score (PHES). A subset was also tested with the simplified animal naming test (S-ANT1). Patients were followed for OHE development and death/liver transplantation (LTx). 

Results: A total of 1462 patients with a median model of end-stage liver disease of 11 were included (Child-Pugh (CP) stages: A 47%/B 41%/C 12%). Median follow-up time was 19 months, during which 336 (23%) patients developed an OHE episode and 464 (32%) reached the composite end point of death/LTx (369 deaths, 95 LTx). In multivariable analyses, MHE (defined by PHES) was associated with the development of OHE (subdistribution hazard ratio 1.74, p < 0.001) and poorer LTx-free survival (hazard ratio 1.53, p < 0.001) in the total cohort as well as in the subgroup of patients without a history of OHE. In subgroup analyses, MHE (defined by PHES) was associated with OHE development in patients with CP B, whereas there was no association in patients with CP A or C. In the subgroup of patients with available S-ANT1, MHE (defined by S-ANT1) was independently associated with OHE development. Combined testing (PHES+S-ANT1) was superior to single testing for predicting OHE and poorer LTx-free survival. Conclusions: This large multicenter study demonstrates that screening for MHE is a useful tool for predicting OHE and poorer survival.