Author information

¹Department of Neurology, Hannover Medical School, Carl-Neuberg-Straße 1, 30625 Hannover, Germany.

²Department of Gastroenterology, Hepatology, Infectious Diseases and Endocrinology, Hannover Medical School, Carl-Neuberg-Straße 1, 30625 Hannover, Germany.

Abstract

Background aims: Current guidelines recommend the assessment for minimal hepatic encephalopathy (mHE) in patients with liver cirrhosis. Various efforts were made in finding tools that simplify the diagnosis. Here, we compare the six most frequently used tests for their validity and their predictive value for overt hepatic encephalopathy (oHE), rehospitalization and death.

Approach results: 132 cirrhotic patients underwent the PSE-Syndrome-Test yielding the psychometric hepatic encephalopathy score (PHES), Animal Naming Test (ANT), Critical Flicker Frequency (CFF), Inhibitory Control Test (ICT), EncephalApp (Stroop) and Continuous Reaction Time Test (CRT). Patients were monitored for 365 days regarding oHE development, rehospitalization and death. 23 patients showed clinical signs of HE grade 1-2 at baseline. Of the remaining 109 neurologically unimpaired patients, 35.8% had abnormal PHES and 44% abnormal CRT. Percentage of abnormal Stroop (79.8% vs 52.3%), ANT (19.3% vs 51.4%), ICT (28.4% vs 36.7%) and CFF results (18.3% vs 25.7%) changed significantly when adjusted norms were used for evaluation instead of fixed cut-offs. All test results correlated significantly with each other (p<0.05), except of CFF. During follow-up, 24 patients developed oHE, 58 were re-admitted to hospital and 20 died. Abnormal PHES results were linked to oHE development in the multivariable model. No other adjusted test demonstrated predictive value for any of the investigated endpoints.

Conclusions: Where applicable, the diagnosis of mHE should be made based on adjusted norm values for the tests, exclusively. The mHE tests cannot be equated with one another and have an overall limited value in predicting clinical outcomes.