Diagnosis of minimal hepatic encephalopathy in patients with cirrhosis: Should we bury psychometric tests?
Authors: Dominique Thabut, Kiyoka Kinugawa, Nicolas Weiss
Journal: Hepatology (2013)

We read with great interest the article by Berlioux et al.1 In an elegant study, the authors showed that critical flicker frequency (CFF) was able to accurately predict the occurrence of overt hepatic encephalopathy (OHE) after transjugular intrahepatic portosystemic shunt (TIPS) placement in patients with cirrhosis. They concluded that minimal HE (MHE) was a condition favoring the development of OHE. However, in this study, psychometric hepatic encephalopathy sum score (PHES), which is usually recommended for the diagnosis of MHE, was not able to predict the development of OHE. We wanted to outline that PHES performances were probably underestimated in the present study, because it has never been validated in France. This synthetic score is generated from a battery of five tests.2 In our country, only two out of the five tests (NCT-A and NCT-B) have been standardized, meaning that their normal values are well defined for controls; for two tests, guidelines were not even translated into French. PHES was validated in Spain, Germany, India, Italy, and Korea. There are discrepancies between countries regarding variables considered and ways of computing results of each test. A Korean study compared three ways of scoring, and found significant differences in the proportion of MHE with each method.3 Hence, PHES should be standardized in France before using it for French subjects. The authors used the Spanish algorithm, including education-adjusted values which proved to be reliable in Latin countries with similar distribution of educational level and schooling system.4 Whereas this way of testing is reliable in France it remains to be proven. We aimed to assess MHE in cirrhosis patients using the same algorithm as Berlioux et al., as well as other tests validated for the diagnosis of cognitive impairment (Mini-Mental State Examination [MMSE] and Montreal Cognitive Assessment [MOCA]). Out of 45 cirrhosis patients (Child-Pugh score = 7.6 ± 3.0 and MELD score = 12.5 ± 3.1), 14 presented with abnormal MMSE or MOCA (MMSE = 24 ± 1, MOCA = 23 ± 2), but no MHE at PHES (PHES = 0.52 ± 2.2)). As other causes of cognitive impairment were ruled out, it is probable that MHE was underdiagnosed by PHES in those patients. Therefore, our findings, added to those of Berlioux et al., require a validation of PHES in each country before assessing performances of this score in a pathological setting. Dominique Thabut, M.D., Ph.D.1,2 Kiyoka Kinugawa, M.D., Ph.D.1,3,4 Nicolas Weiss, M.D., Ph.D.1,5 1Assistance Publique – Hôpitaux de Paris Brain Liver Pitié-Salpêtrière (B-LIPS) study group Groupement Hospitalier Pitié-Salpêtrière-Charles Foix Paris, France 2Assistance Publique – Hôpitaux de Paris UF de Soins Intensifs d'Hépato-gastroentérologie Groupement Hospitalier Pitié-Salpêtrière-Charles Foix Paris, France 3Institut Hospitalo-Universitaire-A (IHU-A) Assistance Publique – Hôpitaux de Paris,Unité d'Explorations Fonctionnelles du Sujet Agé Groupement Hospitalier Pitié-Salpêtrière-Charles Foix Paris, France 4Université Pierre et Marie Curie et CNRS Institut de la LongévitéUMR 7102 Neurobiologie des Processus Adaptatifs Ivry-sur-Seine, France 5Institut Hospitalo-Universitaire-A (IHU-A)Assistance Publique – Hôpitaux de Paris Unité de réanimation neurologique Groupement Hospitalier Pitié-Salpêtrière-Charles Foix Paris, France