Development of a Cognitive Tool for Rapid and Reliable Screening of Minimal Hepatic Encephalopathy: Pilot Study

Overview

The aim of this project is to evaluate the sensitivity and specificity of a cognitive test toward the presence of minimal hepatic encephalopathy (MHE). MHE is a neurological complication due to hepatic dysfunction and/or the presence of porto-systemic shunts defined by the presence of neurocognitive impairments (NI). Other factors of brain injury may cause NI independently from the liver condition making the differential diagnosis difficult using available cognitive tests (ANT Animal Naming Test, PHES Psychometric Hepatic Encephalopathy Score, CFF Critical Flicker Frequency test). The cognitive test evaluated in this project is a construction task using construction blocks, allowing the evaluation of psychomotor speed, executive functions, attention, and episodic memory. The measures will be compared to other cognitive tests validated for the evaluation of the targeted cognitive functions (PHES, Mesulam Cancelling task, Rey-Osterrieth complex figure, Free and Cued Selective Reminding Test) and cognitive tests validated for the diagnosis of MHE (PHES, ANT, CFF). The diagnosis of MHE is based on an adjudication committee including a multimodal assessment of MHE (brain MRI with spectroscopy, EEG, blood sample, neuropsychological assessment), allowing the evaluation of comorbidities such as other factors of brain injury.

Hepatic encephalopathy (HE), corresponding to all the neurocognitive symptoms caused by liver damage and/or the presence of portosystemic shunts. HE can take several forms depending on its intensity, ranging from subtle neuropsychological abnormalities that are difficult to detect during a routine interview ("minimal" HE, MHE) to temporospatial disorientation and confusion that can lead to coma ( "overt" HE, OHE). MHE can significantly impair the quality of life of patients and caregivers; it is associated with a poorer prognosis of liver pathology and a significantly more frequent occurrence of OHE. Detection of MHE is complex, and involves the convergence of a large number of tests recognized as sensitive: venous ammonia level, electroencephalogram, MRI with spectroscopy, complete neuropsychological assessment. Today, there is no unanimously recognized Gold Standard. The objective of this research project is to develop a cognitive test to detect HE sensitively and specifically, in order to detect HE. To do this, the investigators will evaluate the qualities of a rapid and accessible test. It is a test made up of building blocks to assess psychomotor speed, attention, executive functions and episodic memory. If it proves sensitive and specific enough for the diagnosis of MHE, it could be disseminated and allow the screening of MHE. To do this, the investigators will compare the block construction test to other neuropsychological examinations validated in the diagnosis of MHE (PHES: Psychometric Hepatic Encephalopathy Score, CFF: Critical Flicker Frequency test, ANT: Animal Naming Test). These examinations are reference cognitive tests in the diagnosis of MHE, but the results between these tests diverge and do not currently make it possible to replace all of the clinical examinations described above. The investigators will also compare the construction block test to cognitive tests validated for the evaluation of the targeted cognitive functions (ROCF Rey-Osterrieth complex figure, FCSRT Free and Cued Selective Reminding test, MCT Mesulam cancelling task). The diagnosis of MHE is based on an adjudication committee including a multimodal assessment of MHE (brain MRI with spectroscopy, EEG, blood sample, neuropsychological assessment), allowing the evaluation of comorbidities such as other factors of brain injury. Main objective : to evaluate the sensitivity and specificity of the construction test to the presence of MHE. Secondary objectives: 1. Comparison of screening qualities of the construction test to MHE diagnosis validated tests (PHES, CFF, ANT) 2. Evaluate the impact of the presence of comorbidities (factors of brain injury) in the results of the construction test. 3. Evaluate the psychometric qualities of the construction test compared to validated neuropsychological tests.