Assessment of low-grade hepatic encephalopathy: a critical analysis

Abstract

Background/aims: The value of paper-pencil tests and West-Haven-criteria for assessment of low-grade hepatic encephalopathy under conditions of a randomized, double-blind, placebo-controlled, clinical trial was evaluated in a cohort of 217 cirrhotics.

Methods: Patients were graded at least twice clinically for severity of hepatic encephalopathy and tested concomitantly with a recommended psychometric test battery.

Results: Re-evaluation of the study documentation showed that at study entry 33% and during the study even 50% of the patients were wrongly allocated to minimal or overt hepatic encephalopathy. Despite the participating physicians' training, 31% of the number-connection-tests-A, 20% of the number-connection-tests-B and 28% of the line-tracing-test were in retrospect considered invalid by an independent psychologist. Neither the Portosystemic-Encephalopathy-Syndrome (PSE) test nor the Psychometric-Hepatic-Encephalopathy-Sum (PHES)-score reliably picked up clinical improvement in the individual patient. Although these test scores could statistically differentiate between patients with minimal and overt hepatic encephalopathy, the clinical classification of individual patients into one of the groups will have a high rate of error. The PHES-Score was less balanced than the score derived from the PSE-Syndrome-Test.

Conclusions: Inaccuracies in conducting paper-pencil tests together with the subjectivity and incorrectness of clinical HE-grading question the usefulness of West-Haven-criteria and paper-pencil tests including related scores for quantification of low-grade HE at least in multicenter approaches.