Overt hepatic encephalopathy impairs learning on the EncephalApp stroop which is reversible after liver transplantation

Hepatic encephalophathy: management and diagnostic therapeutic assistance path of Ligurian Local Health Company 3 (ASL3)

Hepatic encephalophathy (HE) is a neuropsychiatric syndrome with a prevalence in the cirrhotic population ranging from 20 to 80%. HE is a cause of inappropriate hospitalization, caregiver burdening and increased social costs. There is need to create dedicated care pathways to better manage patients and support family caregivers. The data used for the preparation of this diagnostic therapeutic assistance path (DTAP) are based on a detailed analysis of the scientific literature published before June 30, 2022 (PubMed, Web of Science, Scopus, Google Scholar). Furthermore, in the process of developing this work, we consulted in particular the guidelines/ position papers of International Society for Hepatic Encephalopathy and Nitrogen Metabolism (ISHEN), Italian Association for the Study of the Liver (AISF), European Association for the Study of the Liver (EASL), American Association for the Study of Liver Diseases (AASLD), Italian Society on Alcohol (Società Italiana di Alcologia [SIA]) and other relevant papers. DTAP was created based on the most recent recommendations of the international scientific literature. The present DTAP highlight the need for a multidisciplinary activity integrated with territorial medicine in close connection with caregivers. This guarantees improved therapeutic adherence, hospital readmission reduction, improved quality of life for patients and caregivers and a significant reduction in costs.

Evaluating a Novel, Portable, Self-Administrable Device ("Beacon") That Measures Critical Flicker Frequency as a Test for Hepatic Encephalopathy

INTRODUCTION

We compared critical flicker frequency (CFF) thresholds obtained using a novel portable device "Beacon" with thresholds from the commercially available Lafayette Flicker Fusion System (Lafayette-FFS) in patients with cirrhosis.

METHODS

One hundred fifty-three participants with chronic liver disease underwent CFF testing using Beacon and Lafayette-FFS with a method-of-limits and/or forced-choice protocol.

RESULTS

Beacon demonstrated excellent test-retest reliability (intraclass correlation 0.91-0.97) and good correlation with the Lafayette-FFS values (intraclass correlation 0.77-0.84). Forced-choice CFF were on average 4.1 Hz higher than method-of-limits descending CFFs.

DISCUSSION

Beacon can be self-administered by patients with chronic liver disease and cirrhosis to measure CFF, a validated screening test for minimal hepatic encephalopathy.

Cognitive Impairment in Liver Transplant Recipients With a History of Cirrhosis: A Systematic Review

Cognitive impairment is common among patients with cirrhosis and may persist post-transplantation. This systematic review seeks to (1) describe the prevalence of cognitive impairment in liver transplant (LT) recipients with a history of cirrhosis, (2) describe risk factors for this population, and (3) describe associations between post-transplant cognitive impairment and quality outcome measures.

Methods

Studies in PubMed, Embase, Scopus, PsychINFO, and the Cochrane Database of Controlled Trials were included through May 2022. Inclusion criteria included (1) population - LT recipient, age ≥18 y, (2) exposure - history of cirrhosis before transplant, and (3) outcome - cognitive impairment after transplant (per validated cognitive testing). Exclusion criteria included (1) wrong study type, (2) abstract-only publication, (3) full-text unavailable, (4) wrong population, (5) wrong exposure, and (6) wrong outcome. The risk of bias was assessed using the Newcastle-Ottawa Scale and the Appraisal tool for Cross-Sectional Studies. The Grading of Recommendations, Assessment, Development, and Evaluations system was used to assess evidence certainty. Data from individual tests were categorized into six cognitive domains: attention, executive function, working memory, long-term memory, visuospatial, and language.

Results

Twenty-four studies were included covering 847 patients. Follow-up ranged from 1 mo to 1.8 y after LT. Studies had a median of 30 (interquartile range 21.5-50.5) patients. The prevalence of cognitive impairment after LT ranged from 0% to 36%. Forty-three unique cognitive tests were used, the most common being the Psychometric Hepatic Encephalopathy Score. The most frequently assessed cognitive domains were attention (10 studies) and executive function (10 studies).

Conclusions

The prevalence of cognitive impairment after LT varied across studies depending on cognitive tests utilized and follow-up duration. Attention and executive function were most impacted. Generalizability is limited due to small sample size and heterogeneous methodology. Further studies are needed to examine differences in the prevalence of post-LT cognitive impairment by etiology, risk factors, and ideal cognitive measures.

Diagnosis and management of hepatic encephalopathy: The French recommendations

Hepatic encephalopathy (HE) is a frequent and severe complication of liver disease with poor patient outcomes. However, it is a poorly understood complication, with no consensus for diagnosis. Therefore, HE is often underdiagnosed. Differential diagnosis may be cumbersome because of non-specific symptoms, such as confusion, cognitive disorders, the aetiological factors of cirrhosis and comorbidities, which are often observed in cirrhotic patients. Therefore, an overt or covert form of HE should be systematically investigated. Advice is provided to drive patient work-up. Effective treatments are available to prevent or treat HE bouts, but the issue of single or combination therapy has not been resolved. Transjugular intrahepatic portosystemic shunt (TIPS) placement largely improved the prognosis of cirrhotic patients, but HE occurrence of HE is often a fear, even when post-TIPS HE can be avoided by a careful selection of patients and preventive treatment. HE is an indication of liver transplantation. However, its reversibility post-transplantation and the consequences of transplantation in patients with other causes of neurological disorders remain controversial, which supports the performance of an extensive work-up in expert centres for this subset of patients. The present guidelines assist clinicians in the diagnosis of the overt or covert form of HE to implement curative and preventive treatments and clarify which patients require referral to expert centres for consideration for liver transplantation. These guidelines are very clinically oriented and address different frequent clinical issues to help physicians make bedside decisions.

EncephalApp Stroop Test validation for the screening of minimal hepatic encephalopathy in Brazil

INTRODUCTION AND OBJECTIVES

The EncephalApp Stroop Test was developed to more easily diagnose minimal hepatic encephalopathy (MHE). A cut-off of >274.9sec (ONtime+OFFtime) reached a 78% sensitivity and 90% specificity in the validation study, but it has been poorly studied in Brazil. We aim to analyze the usefulness of this diagnostic method and to describe a cut-off value to screen MHE in Brazil.

METHODS

In this cross-sectional and single-center study, three positive psychometric tests defined the diagnosis of MHE as the gold standard. We evaluated gender, age, education, familiarity with smartphones, etiology of cirrhosis, Child-Pugh/MELD scores, and previous hepatic encephalopathy (HE). Healthy controls and patients without HE were compared for the task validation. The Chi-square and Mann-Whitney tests, logistic regression analysis, and ROC curves were used for statistical evaluation.

RESULTS

We included 132 patients with cirrhosis (61% male) and 42 controls (62% male) around 51y. Sixty-three were diagnosed with MHE on psychometric tests and 23 had clinical HE. Viral hepatitis (38%) was the major etiology of cirrhosis. The median MELD was 10 and Child-Pugh A was more frequent (70%). There was no significant difference in test results between controls and patients without HE. There was also no influence of gender, age, education, and familiarity with smartphones in the test results. Child-Pugh A was associated with MHE (p=0.0106). A cut-off of >269.8sec (ONtime+OFFtime) had an 87% sensitivity and 77% specificity to detect MHE (p=0.002).

CONCLUSION

This is a valid and reliable tool for screening MHE. However, optimal cut-off values need to be validated locally.

Psychometric methods for diagnosing and monitoring minimal hepatic encephalopathy -current validation level and practical use

Hepatic encephalopathy (HE) is cerebral dysfunction caused by liver failure and inflicts 30-40% of patients with liver cirrhosis during their disease course. Clinically manifest HE is often preceded by minimal HE (MHE) - a clinically undetectable cognitive disturbance closely associated with loss of quality of life. Accordingly, detecting and treating MHE improve the patients' daily functioning and prevent HE-related hospital admissions. The scope of this review article is to create an overview of the validation level and usage of psychometric tests used to detect MHE: Portosystemic hepatic encephalopathy test, continuous reaction time test, Stroop EncephalApp, animal naming test, critical flicker frequency test, and inhibitory control test. Our work is aimed at the clinician or scientist who is about to decide on which psychometric test would fit best in their clinic, cohort, or study. First, we outline psychometric test validation obstacles and requirements. Then, we systematically approach the literature on each test and select well-conducted studies to answer the following questions:• Which percentage of patients with cirrhosis does the test deem as having MHE?• Is the test able to predict clinically manifest HE?• Is there a well-known test-retest variation and inter-observer variation?• Is the test able to detect a treatment response?• Is the test result affected by age, educational level, gender, or comorbidities?

Hepatic Encephalopathy and Liver Transplantation: The Past, Present, and Future Toward Equitable Access

Cirrhosis is a debilitating chronic disease with high morbidity and mortality, with the only real cure being liver transplantation (LT). Currently, we allocate organs for transplantation based on the Model for End-Stage Liver Disease-Sodium (MELD-Na) score that does not account for hepatic encephalopathy (HE). HE affects patients, families, and the health care system because of high rates of recurrence and major readmission burden. Moreover, HE casts a long shadow even after LT. Accounting for HE and incorporating it into the current allocation system has many proponents, but the framework to do this is currently lacking because of differences in consensus or in operationalization parameters. We review the latest evidence of the burden of HE, management of HE before and after LT, and evaluate pros and cons of several methods of diagnosing HE objectively to ensure early and equitable access to LT in this underserved population.

Cognitive Impairment After Resolution of Hepatic Encephalopathy: A Systematic Review and Meta-Analysis

Hepatic encephalopathy (HE) is one of the most disabling metabolic diseases. It consists of a complication of liver disease through the action of neurotoxins, such as excessive production of ammonia from liver, resulting in impaired brain function. Its prevalence and incidence are not well known, although it has been established that up to 40% of cirrhotic patients may develop HE. Patients with HE episodes display a wide range of neurological disturbances, from subclinical alterations to coma. Recent evidence suggests that the resolution of hepatic encephalopathy does not fully restore cognitive functioning in cirrhotic patients. Therefore, the aim of this review was to evaluate the evidence supporting the presence of lingering cognitive deficits in patients with a history of HE compared to patients without HE history and how liver transplant affects such outcome in these patients. We performed two distinct meta-analysis of continuous outcomes. In both cases the results were pooled using random-effects models. Our results indicate that cirrhotic patients with a history of HE show clear cognitive deficits compared to control cirrhotic patients (Std. Mean Difference (in SDs) = −0.72 [CI 95%: −0.94, −0.50]) and that these differences are not fully restored after liver transplant (Std. Mean Difference (in SDs) = −0.48 [CI 95%: −0.77, −0.19]).

High-Fat Diet Modulates Hepatic Amyloid β and Cerebrosterol Metabolism in the Triple Transgenic Mouse Model of Alzheimer's Disease

Obesity and diabetes are strongly associated not only with fatty liver but also cognitive dysfunction. Moreover, their presence, particularly in midlife, is recognized as a risk factor for Alzheimer's disease (AD). AD, the most common cause of dementia, is increasingly considered as a metabolic disease, although underlying pathogenic mechanisms remain unclear. The liver plays a major role in maintaining glucose and lipid homeostasis, as well as in clearing the AD neuropathogenic factor amyloid-β (Aβ) and in metabolizing cerebrosterol, a cerebral-derived oxysterol proposed as an AD biomarker. We hypothesized that liver impairment induced by obesity contributes to AD pathogenesis. We show that the AD triple transgenic mouse model (3xTg-AD) fed a chow diet presents a hepatic phenotype similar to nontransgenic controls (NTg) at 15 months of age. A high-fat diet (HFD), started at the age of 6 months and continued for 9 months, until sacrifice, induced hepatic steatosis in NTg, but not in 3xTg-AD mice, whereas HFD did not induce changes in hepatic fatty acid oxidation, de novo lipogenesis, and gluconeogenesis. HFD-induced obesity was associated with a reduction of insulin-degrading enzyme, one of the main hepatic enzymes responsible for Aβ clearance. The hepatic rate of cerebrosterol glucuronidation was lower in obese 3xTg-AD than in nonobese controls (P < 0.05) and higher compared with obese NTg (P < 0.05), although circulating levels remained unchanged. Conclusion: Modulation of hepatic lipids, Aβ, and cerebrosterol metabolism in obese 3xTg-AD mice differs from control mice. This study sheds light on the liver-brain axis, showing that the chronic presence of NAFLD and changes in liver function affect peripheral AD features and should be considered during development of biomarkers or AD therapeutic targets.

USE OF THE STROOP ENCEPHALAPP FOR COVERT HEPATIC ENCEPHALOPATHY SCREENING IN CIRRHOTIC PATIENTS IN SOUTHERN BRAZIL

BACKGROUND

Covert hepatic encephalopathy (CHE) is difficult to detect due to the lack of easily applicable screening tools. The Stroop EncephalApp is a smartphone application already validated for CHE screening. However, its applicability to the Brazilian population is not known.

OBJECTIVE

To estimate the prevalence of CHE and evaluate the use of Stroop EncephalApp in a cirrhotic population in Brazil.

METHODS

In this cross-sectional study, we evaluated 99 patients previously diagnosed with liver cirrhosis in a Private Hospital in Curitiba/PR. Patients were initially submitted to the mini mental state examination (MMSE) to exclude individuals with dementia. After, the Psychometric Hepatic Encephalopathy Score (PHES) test was performed and lastly, the Stroop EncephalApp test. Results were adjusted for age, sex and education levels to evaluate the accuracy of the app on detecting the disease, comparing its results with the gold standard method (PHES). Patients with one or more of the following were excluded: dementia, inadequate MMSE score, illiteracy, color blindness, history of drugs/alcohol abuse within the past 3 months and previous or actual episodes of encephalopathy. The statistical analysis was performed by SPSS 2.0 and the significance adopted by 5%.

RESULTS

We included 82 individuals in the final analysis. Among these patients, 29 were diagnosed with CHE by the PHES test (35.36% prevalence) and 28 of those obtained equal diagnosis by the Stroop EncephalApp (96.6% sensitivity). A total of 53 patients obtained negative results for CHE by PHES, while the Stroop test classified 27 of them as having the disease. In the multivariate analysis, high levels of education were associated with better performance during the tests. No significant relationship was observed between age and sex with the probability of diagnosing CHE through the PHES test.

Cognitive Tests and Stool Frequency at Hospital Discharge Do Not Predict Outcomes in Hepatic Encephalopathy

OBJECTIVES

Hepatic encephalopathy (HE) is associated with hospital readmissions and mortality. We sought to determine whether cognitive testing and stool frequency at discharge predicted 30-day readmission or death in cirrhotic patients admitted with overt HE.

METHODS

We approached consecutive inpatients with cirrhosis and overt HE when they were within 48 hours of discharge. Patients underwent cognitive tests, including Psychometric Hepatic Encephalopathy Score (PHES), and stool frequency was documented. Chart review identified Model for End-Stage Liver Disease-sodium (MELD-Na) and the presence of non-HE extrahepatic organ failures. Cox proportional hazards models were used to evaluate predictors of time to the primary composite outcome of hospital readmission for HE or death within 30 days, censoring for liver transplantation.

RESULTS

Of 51 patients consented and enrolled, 14 patients met the primary composite outcome. In unadjusted Cox models, 4 variables predicted HE readmission or death: MELD-Na (hazard ratio [HR] 1.10 [1.01-1.20], P = 0.03), respiratory failure (HR 4.26 [1.47-12.35], P = 0.008), total number of HE extrahepatic organ failures (HR 1.79 [1.12-2.88], P = 0.02), and score on a PHES subtest, Number Connection Test A (per 30 seconds; HR 1.25 [1.06-1.47], P = 0.01). PHES and 24-hour stool frequency did not predict the primary outcome. When controlling for MELD-Na, respiratory failure predicted the primary outcome (HR 3.67 [1.24-10.86], P = 0.02).

CONCLUSION

Cognitive testing and stool frequency at discharge did not predict poor outcomes in patients admitted with HE, while respiratory failure appeared to be a strong predictor.

Cognitive Function in Liver Transplant Recipients Who Survived More Than 6 Months

Introduction:

Current research in the areas of liver transplant and cognitive function has primarily examined cognitive changes from pre- to 1-year posttransplant, resulting in an insufficient understanding of cognitive trajectory beyond early periods of transplant and its impact on self-management. This study aimed (1) to describe global and domain-specific cognitive function in liver transplant recipients who survived more than 6 months after transplant and (2) to describe patient and clinical characteristics of recipients with impaired global and/or domain-specific cognitive function. Further, this study explored the potential relationships between cognitive function and self-management by examining differences in cognitive function by levels of self-management.

Design:

This secondary data analysis included 107 adult liver transplant recipients, who had a functioning transplant for at least 6 months. Data of cognitive function, demographic and clinical characteristics, and self-management were extracted for this study. T tests, Mann-Whitney tests, and Kruskal-Wallis tests were used to examine differences in cognitive function by variables.

Results:

More than half of the recipients had global cognitive impairment. Significant differences were found in global and domain-specific cognitive function. Older, male, married, or deceased donor recipients had lower cognitive test scores than younger, female, single, or living donor recipients. There were no significant differences in global and domain-specific cognitive function by time since transplant and levels of self-management.

Discussion:

Future longitudinal studies should examine the long-term trajectory of cognitive function posttransplant. Other factors such as caregivers’ participation in self-management should be accounted for in future studies when examining the relationship between cognitive function and self-management.