Utility of the EncephalApp Stroop Test for covert hepatic encephalopathy screening in Chinese cirrhotic patients

Chinese Guidelines on the Management of Hepatic Encephalopathy in Cirrhosis (2024)

With progress in basic and clinical research on hepatic encephalopathy in cirrhosis worldwide, the Chinese Society of Hepatology of the Chinese Medical Association has invited experts in relevant fields to revise the 2018 "Chinese Guidelines on the Management of Hepatic Encephalopathy in Cirrhosis." The updated guidelines provide recommendations for the clinical diagnosis, treatment, and both primary and secondary prevention of hepatic encephalopathy in cirrhosis.

External validation of EncephalApp Stroop test to screen minimal hepatic encephalopathy patients with nonalcoholic cirrhosis

BACKGROUND

Neurocognitive impairment, including minimal hepatic encephalopathy (MHE) and overt hepatic encephalopathy, is one of the most common complications of all types of primary liver diseases, such as hepatitis B, biliary cholangitis, and autoimmune hepatitis. The EncephalApp Stroop test is a smartphone application-based test that is time-saving for MHE screening. However, neurocognitive impairment is different between alcoholic cirrhosis patients and nonalcoholic cirrhosis patients, so the cutoff value for MHE diagnosis might be inflated.

AIM

To validate the Stroop test in nonalcoholic cirrhosis patients.

METHODS

This external validation was performed at the National Center for Infectious Diseases (Beijing). Liver cirrhosis patients aged between 18 and 65 years who voluntarily enrolled in the study and provided signed informed consent were included. The Psychometric Hepatic Encephalopathy Score (PHES) test was used as the standard diagnostic criterion for MHE. The EncephalApp Stroop test was then performed on the iPad, including two sessions of tests (“off” and “on”) to measure patients’ ability to differentiate between numbers and letters. We assessed the performance of the EncephalApp Stroop test in terms of the area under the curve (AUC), sensitivity, specificity, positive predictive value, and negative predictive value, with the PHES as the standard criterion.

RESULTS

A total of 160 nonalcoholic cirrhosis patients were included in this validation study, including 87 (54.4%) patients without MHE and 73 (45.6%) patients with MHE. Taking the PHES as the gold standard, the EncephalApp Stroop test performed well for nonalcoholic liver cirrhosis patients in terms of “off” time [AUC: 0.85, 95% confidence interval (CI): 0.79-0.91] and “on + off” time (AUC: 0.85, 95%CI: 0.80-0.91); however, total runs of “off” session (AUC: 0.61, 95%CI: 0.52-0.69), total runs of “on” session (AUC: 0.57, 95%CI: 0.48-0.65), and “on – off” time (AUC: 0.54, 95%CI: 0.44-0.63) were comparatively low. The optimal cutoff points were “off” time > 101.93 seconds and “on + off” time > 205.86 seconds, with sensitivities of 0.84 and 0.90, specificities of 0.77 and 0.71, positive predictive values of 0.75 and 0.72, and false-positive values of 0.85 and 0.89, respectively.

CONCLUSION

Our results suggest that different cutoffs should be used for the EncephalApp Stroop tool for MHE screening between alcoholic and nonalcoholic living patients, which is a critical check before generalization to screen for neurocognitive impairment among the whole population of chronic liver diseases.

Stroop test, Quickstroop, and the 1-min animal naming test for minimal hepatic encephalopathy diagnosis: A multicenter study in Mexico

INTRODUCTION AND OBJECTIVES

Although the Psychometric Hepatic Encephalopathy Score (PHES) remains the gold standard in diagnosing minimal hepatic encephalopathy (MHE), its complexity limits its application in clinical practice. While more convenient tests, such as the Stroop test, Quickstroop, and the 1-min animal naming test (ANT-1), have emerged, they haven't been validated in our setting. Our objective was to validate these tests in our population.

PATIENTS AND METHODS

This multicenter, observational, descriptive, and cross-sectional study was conducted in three hospitals in northeastern Mexico. MHE was defined as a PHES <-4. We included patients with cirrhosis aged >15 years without a history of overt hepatic encephalopathy. Data regarding sex, age, education, Child-Pugh/MELD-Na scores, etiology of cirrhosis, diabetes, hypertension, obesity, ascites, and clinically significant portal hypertension was collected. Fisher's exact test, Mann-Whitney U test, and receiver operating characteristic (ROC) curves were used for statistical analysis.

RESULTS

Of the 121 patients included, 35.5 % were diagnosed with MHE. The presence of MHE was significantly associated with education level, years of study, and scores in the Stroop test, Quickstroop, and ANT-1. The AUROC curves were 77.9 %, 74.6 %, and 72.7 % for the Stroop test, Quickstroop, and ANT-1, respectively. The resulting cut-off points were 218.398 (sensitivity: 74 %; specificity: 74 %), 40.535 (sensitivity: 77 %; specificity: 68 %), and <16 animals (sensitivity: 58 %; specificity: 79 %), respectively.

CONCLUSIONS

These tests are valid diagnostic tools for detecting MHE in our population. Their simpler use and applicability could increase the early diagnosis of MHE and prompt primary prophylaxis initiation for overt hepatic encephalopathy.

Correlation of ammonia and blood laboratory parameters with hepatic encephalopathy: A systematic review and meta-analysis

BACKGROUND AND OBJECTIVES

Emerging research suggests that hyperammonemia may enhance the probability of hepatic encephalopathy (HE), a condition associated with elevated levels of circulating ammonia in patients with cirrhosis. However, some studies indicate that blood ammonia levels may not consistently correlate with the severity of HE, highlighting the complex pathophysiology of this condition.

METHODS

A systematic review and meta-analysis through PubMed, Scopus, Embase, Web of Science, and Virtual Health Library were conducted to address this complexity, analyzing and comparing published data on various laboratory parameters, including circulating ammonia, blood creatinine, albumin, sodium, and inflammation markers in cirrhotic patients, both with and without HE.

RESULTS

This comprehensive review, which included 81 studies from five reputable databases until June 2024, revealed a significant increase in circulating ammonia levels in cirrhotic patients with HE, particularly those with overt HE. Notably, significant alterations were observed in the circulating creatinine, albumin, sodium, interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNFα) in HE patients.

CONCLUSIONS

These findings suggest an association between ammonia and HE and underscore the importance of considering other blood parameters such as creatinine, albumin, sodium, and pro-inflammatory cytokines when devising new treatment strategies for HE.

Detection of minimal hepatic encephalopathy in patients with cirrhosis based on the Stroop-CN model (NCRCID-CHESS 2106): a prospective multicenter study

Minimal hepatic encephalopathy (MHE) has a substantial impact on the clinical outcomes and quality of life (QOL) of patients with cirrhosis. However, timely diagnosis and intervention are challenging due to sophisticated diagnostic methods. In this study, 673 healthy controls and 905 patients with cirrhosis were screened, and 660 healthy controls and 757 patients with cirrhosis, divided into the test (292 patients) and validation (465 patients) cohort, were analyzed after screening. A diagnostic model of the Stroop test (Stroop-CN) was constructed by multivariate linear regression based on the results of healthy controls. The prevalence of MHE and the comparison results with psychometric hepatic encephalopathy score through the Stroop-CN model were stable in the test and validation cohorts. Moreover, the prevalence of MHE remained significantly higher in patients with worse disease conditions marked as high Child-Pugh grades and the Model for End-stage Liver Disease and Sodium (MELD-Na) scores in the test and validation cohort. The EuroQol 5-D questionnaire revealed that patients with MHE had a worse QOL than those without MHE both in the test and validation cohort. In conclusion, an easy and practical Stroop-CN model for MHE diagnosis based on the EncephalApp is established. It is found that a considerable number of Chinese patients with cirrhosis experience MHE, which significantly impacts their QOL.

Covert hepatic encephalopathy is associated with aggressive disease progression and poor survival in patients with cirrhosis

OBJECTIVES

Covert hepatic encephalopathy (CHE) negatively affects the health-related quality of life and increases the risk of overt HE (OHE) in patients with liver cirrhosis. However, the impact of CHE on long-term patient outcomes remains controversial. This study aimed to explore the association between CHE and disease progression and survival among cirrhotic patients.

METHODS

This was a single-center prospective study that enrolled 132 hospitalized patients with cirrhosis, with an average follow-up period of 45.02 ± 23.06 months. CHE was diagnosed using the validated Chinese standardized psychometric hepatic encephalopathy score.

RESULTS

CHE was detected in 35.61% cirrhotic patients. During the follow-up, patients with CHE had a higher risk of developing OHE (log-rank 5.840, P = 0.016), exacerbation of ascites (log-rank 4.789, P = 0.029), and portal vein thrombosis (PVT) (log-rank 8.738, P = 0.003). Cox multivariate regression analyses revealed that CHE was independently associated with the occurrence of OHE, exacerbation of ascites, and PVT. Furthermore, patients with progression of cirrhosis were more likely to be diagnosed as CHE (log-rank 4.462, P = 0.035). At the end of the follow-up, patients with CHE had a lower survival rate compared to those without CHE (log-rank 8.151, P = 0.004). CHE diagnosis (hazard ratio 2.530, P = 0.008), together with elder age and higher Child-Pugh score, were risk factors for impaired survival in cirrhotic patients.

CONCLUSION

CHE is associated with disease progression and poor survival in patients with cirrhosis, indicating that CHE may serve as an independent predictor of poor prognosis among these patients.

EncephalApp Stroop Test for covert hepatic encephalopathy screening in Tunisian cirrhotic patients

Background: Covert hepatic encephalopathy (CHE) is underdiagnosed and is difficult to detect. The EncephalApp Stroop test is validated for its screening. The aim of the study was to define Tunisian norms for the test based on healthy controls norms and to estimate the prevalence of CHE in cirrhotic Tunisian patients. Methods: A prospective, multicenter, cross-sectional study was conducted. Ambulatory or hospitalized cirrhotic patients aged 40 years and over were recruited at 11 centers. Healthy subjects aged 40 years and over were recruited at 8 centers. We used a translated Arabic version of the streamlined EncephalApp Stroop test. The task has two components: "Off" and "On" state depending on the discordance or concordance of the stimuli. Results: 142 patients were included. The mean age was 57.26 years [40-86]. 40 (28.17%) of cirrhotic patients who were included were diagnosed as having a minimal hepatic encephalopathy or CHE. Among the ineligible patients, 22 had overt hepatic encephalopathy. If we consider these patients, the overall prevalence rate of CHE was around 24.39% in cirrhotic patients. It was more frequent in women (34.21% vs 25.96%), and in patients whose level of school education is between 6 and 13 years. Its prevalence does not appear to be affected by gender, MELD score, etiology of cirrhosis and age group of patients, as these variables were independent with respective p according to the chi-square test 0.413; 0.736; 0.663 and 0.1. The stroop times (On / Off and On + Off) correlated significantly with each other, are associated significantly and positively with age (respective Pearson coefficients: 0.578; 0.567 and 0.6). The more the age increases, the more the stroop response times increases (p > 10 -3). Conclusions: EncephalApp Stroop test was an efficient screening tool for CHE in Tunisian cirrhotic patients.

Prediction and prevention of the first episode of overt hepatic encephalopathy in patients with cirrhosis

Hepatic encephalopathy (HE) is one of the most important complications of patients with liver cirrhosis. In addition, HE is associated with a dismal prognosis and has detrimental effects on patients' quality of life. Thus, it is of pivotal importance to identify patients at high risk for overt HE (OHE) in whom primary prophylaxis may be justified. In this narrative review, we aim to provide insight into predictors and prediction tools for a first-time episode of OHE and to scrutinize the current level of evidence of primary prophylaxis. In recent decades, several cognitive tests, composite scores, and blood-based biomarkers have been demonstrated to be predictive of a first-time episode of OHE. Among the best validated are the established tests for minimal HE, such as the Psychometric Hepatic Encephalopathy Score, determination of the critical flicker frequency, Stroop EncephalApp, or the Animal Naming Test. Individualized risk stratification using blood-based biomarkers and cross-sectional imaging (sarcopenia and spontaneous portosystemic shunts) is coming to the fore, but validation in larger multicenter cohorts is often lacking. On the basis of current evidence, a recommendation for primary prophylaxis of a first episode of OHE cannot be made in general. Only 2 studies have investigated the prevention of a first-time OHE episode as the primary endpoint. In this narrative review, we provide a concise overview of the current evidence levels on prediction tools and pharmacological prevention of a first episode of OHE. In addition, we give an outlook on future research targets to improve knowledge on this important topic.

Hepatic Encephalopathy

Hepatic encephalopathy (HE) is brain dysfunction secondary to liver insufficiency or portosystemic shunting. HE is a major burden on patients and caregivers, impairs quality of life and is associated with higher mortality. Overt HE is a clinical diagnosis while Covert HE, needs specialized diagnostic strategies. Mainstay of treatment of HE is nonabsorbable disaccharides such as lactulose as well as rifaximin; however, investigational therapies are discussed in this review. Better tools are needed to prognosticate which patients will go on to develop HE but microbiome and metabolomic-driven strategies are promising. Here we review methods to prevent the HE development and admissions.

QuickStroop, a Shortened Version of EncephalApp, Detects Covert Hepatic Encephalopathy With Similar Accuracy Within One Minute

BACKGROUND & AIMS

Covert hepatic encephalopathy (CHE) is associated with poor outcomes but is often not diagnosed because of the time requirement. Psychometric hepatic encephalopathy score (PHES) is the gold standard against which EncephalApp Stroop has been validated. However, EncephalApp (5 runs each in "Off" and "On" state) can take up to 10 minutes. This study sought to define the smallest number of EncephalApp runs needed for comparable accuracy to the total EncephalApp using CHE on PHES as gold standard.

METHODS

A derivation and a validation cohort of outpatients with cirrhosis who underwent PHES (gold standard) and total EncephalApp was recruited. Data were analyzed for individual runs versus total EncephalApp time versus PHES-CHE. The derivation cohort (n = 398) was split into training (n = 299) and test (n = 99) sets. From the training data set a regression model was created with age, gender, education, and various sums of the "Off" settings. After this, a K-fold cross-validation on the test dataset was performed for both total EncephalApp time and individual Off runs and for the validation cohort.

RESULTS

In both cohorts, Off runs 1 + 2 had statistically similar area under the receiver operating curve and P value to the total EncephalApp for PHES-CHE prediction. The adjusted (age, gender, education) regression formula from the derivation cohort showed an accuracy of 84% to diagnose PHES-CHE in the validation cohort. Time for CHE diagnosis decreased from 203.7 (67.82) to 36.8 (11.25) seconds in the derivation and from 178.2 (46.19) to 32.9 (9.94) seconds in the validation cohort.

CONCLUSIONS

QuickStroop, which is completed within 1 minute, gives an equivalent ability to predict CHE on the gold standard compared with the entire EncephalApp time.

Effects of Low-dose and High-dose Rifaximin in the Treatment of Covert Hepatic Encephalopathy

BACKGROUND AND AIMS

Rifaximin is effective in preventing and treating hepatic encephalopathy (HE). This study aimed to investigate the efficacy and safety of different dosages of rifaximin in the treatment of cirrhotic patients with covert HE (CHE).

METHODS

In this single-center, randomized, controlled, open-label study, CHE was diagnosed using a combination of the psychometric HE score and the EncephalApp Stroop test. Cirrhotic patients with CHE were recruited and randomly assigned to low-dose rifaximin 800 mg/day, high-dose rifaximin (1,200 mg/day), and control groups, and were treated for 8 weeks. The sickness impact profile (SIP) scale was used to evaluate the health-related quality of life (HRQOL) of patients. Forty patients were included in the study, 12 were assigned to the low-dose group, 14 to the high-dose group, and 14 patients to the control group.

RESULTS

The percentage of patients with CHE reversal was significantly higher in both the low-dose (41.67%, 5/12) and high-dose (57.14%, 8/14) groups than in the control group (7.14%, 1/14) at 8 weeks (p=0.037 and p=0.005, respectively). In addition, both doses of rifaximin resulted in significant improvement of the total SIP score compared with the control group. There were no significant differences in the CHE reversal rate, total SIP score improvement, and incidence of adverse event between the low-dose and high-dose groups (p>0.05).

CONCLUSIONS

Low-dose rifaximin reverses CHE and improves HRQOL in cirrhotic patients with comparable effects and safety to high-dose rifaximin.

A shortened Stroop test to identify covert hepatic encephalopathy and predict overt hepatic encephalopathy in patients with cirrhosis

BACKGROUND

Covert hepatic encephalopathy (CHE) adversely affects the clinical outcomes of patients with cirrhosis but remains largely undiagnosed and untreated. Although the Stroop test is a useful method for CHE detection, a faster, simpler, and more accurate test is required to diagnose CHE. This prospective study aimed to develop a new shortened Stroop test that can detect CHE and predict overt hepatic encephalopathy (OHE) in Japanese patients with cirrhosis.

METHODS

Patients who underwent neuropsychological tests (NPT) and the Stroop test between November 2018 and December 2021 were enrolled and followed until OHE occurrence or March 2022. The discriminative ability of various run combinations in the off and on states to detect CHE was evaluated using the area under the receiver-operating characteristic curve (AUC) and compared with that of the total Stroop test time.

RESULTS

Among the 227 eligible patients, the On1-2Time cutoff value of 44.4 s had a comparable discriminative ability with the total Stroop test time to detect CHE, with an AUC of 0.791, a sensitivity of 0.827, and a specificity of 0.685. During a median follow-up period of 16 months, 37 patients developed OHE. On1-2Time ≥ 44.4 s (hazard ratio [HR], 3.93; 95% confidence interval [CI] 1.36-11.36) and serum albumin levels (HR, 0.28; 95% CI 0.11-0.67) were independently associated with OHE occurrence.

CONCLUSIONS

The shortened Stroop test (On1-2Time) is equivalent to the total Stroop test not only for identifying CHE but also for estimating the risk of progression to OHE.

EncephalApp stroop test versus electronic number connection test-A for screening minimal hepatic encephalopathy in patients with liver cirrhosis: a comparative study

OBJECTIVES

Minimal hepatic encephalopathy (MHE) is a common neuropsychiatric complication of liver cirrhosis. Both EncephalApp Stroop test (EncephalApp) and electronic number connection test-A (eNCT-A) are novel computerised psychometric tests for MHE screening. We aimed to compare the efficiency, convenience, accessibility, and acceptability of EncephalApp with that of eNCT-A for MHE screening in cirrhotic patients.

METHODS

Ninety-five patients with hepatitis B-induced liver cirrhosis were included and respectively tested by the psychometric hepatic encephalopathy score (PHES), EncephalApp, and eNCT-A. Using PHES as the gold standard for MHE diagnosis, the efficiency of EncephalApp and eNCT-A for MHE screening were respectively analysed by the receiver operating characteristic (ROC) curve, and the areas under the ROC curve (AUROC) were compared. The convenience, accessibility, and acceptability of PHES, EncephalApp and eNCT-A were respectively evaluated by the 5-point Likert scale.

RESULTS

Fifty-two (55%) of included cirrhotic patients were diagnosed with MHE. The EncephalApp had a sensitivity of 84.6%, a specificity of 74.4%, and an AUROC of 0.836. Meanwhile, the eNCT-A had a sensitivity of 78.8%, a specificity of 83.7%, and an AUROC of 0.845. No significant difference in AUROC was detected between the EncephalApp and eNCT-A (p = .453). Compared with the EncephalApp, the eNCT-A presented better convenience and higher acceptability in cirrhotic patients undergoing MHE screening (p = .019 and p < .001, respectively).

CONCLUSIONS

As with the EncephalApp, the eNCT-A will be a potential home monitoring and point-of-care tool for cirrhotic patients at high risk of MHE.

Validation of EncephalApp_Stroop as screening tool for the detection of minimal hepatic encephalopathy in German patients with liver cirrhosis

BACKGROUND

In contrast to overt hepatic encephalopathy (OHE), the diagnosis of minimal HE (MHE) is challenging in patients with cirrhosis requiring elaborate, specialized testing. The EncephalApp_Stroop is a smartphone-based application established as screening tool for the diagnosis of MHE but has not yet been validated in a German cohort and country specific cut-offs are currently missing.

METHODS

93 patients with cirrhosis were enroled into this study. Psychometric hepatic encephalopathy score (PHES) was used to detect MHE, and a subset of the patients was tested with critical flicker frequency (CFF). All patients underwent testing with EncephalApp_Stroop. Cut-off thresholds for EncephalApp_Stroop were calculated according to Youden's Index and a separate cut-off was determined with focus on sensitivity.

RESULTS

24 (26%) patients had MHE according to PHES. EncephalApp_Stroop had a strong correlation with PHES (r=-0.76, p<0.001), while there was only a modest correlation with CFF (r=-0.51, <0.001). On time as well as on+off time discriminated best between patients with and without MHE with AUROCS of 0.87 for both measures. According to Youden's index, a cut-off of >224.7 s (sec) (on+off time) discriminated best between patients with and without MHE with a sensitivity of 71% and a specificity of 88%. The adjusted cut-off value for on+off time with focus on sensitivity (sensitivity:specificity weighed 2:1) was 185.1 s, yielding an optimized sensitivity of 92% and a negative predictive value of 96%. By using this cut-off as a pre-screening test in a stepwise diagnosis algorithm, elaborate testing with PHES could have been avoided in 49% of all patients.

CONCLUSION

EncephalApp_Stroop may be useful in a stepwise diagnosis algorithm or even as a stand-alone screening tool to detect MHE in German patients with cirrhosis.

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?

The digital transformation of hepatology: The patient is logged in

The rise in innovative digital health technologies has led a paradigm shift in health care toward personalized, patient-centric medicine that is reaching beyond traditional brick-and-mortar facilities into patients' homes and everyday lives. Digital solutions can monitor and detect early changes in physiological data, predict disease progression and health-related outcomes based on individual risk factors, and manage disease intervention with a range of accessible telemedicine and mobile health options. In this review, we discuss the unique transformation underway in the care of patients with liver disease, specifically examining the digital transformation of diagnostics, prediction and clinical decision-making, and management. Additionally, we discuss the general considerations needed to confirm validity and oversight of new technologies, usability and acceptability of digital solutions, and equity and inclusivity of vulnerable populations.

Artificial Intelligence and Its Application to Minimal Hepatic Encephalopathy Diagnosis

Hepatic encephalopathy (HE) is a brain dysfunction caused by liver insufficiency and/or portosystemic shunting. HE manifests as a spectrum of neurological or psychiatric abnormalities. Diagnosis of overt HE (OHE) is based on the typical clinical manifestation, but covert HE (CHE) has only very subtle clinical signs and minimal HE (MHE) is detected only by specialized time-consuming psychometric tests, for which there is still no universally accepted gold standard. Significant progress has been made in artificial intelligence and its application to medicine. In this review, we introduce how artificial intelligence has been used to diagnose minimal hepatic encephalopathy thus far, and we discuss its further potential in analyzing speech and handwriting data, which are probably the most accessible data for evaluating the cognitive state of the patient.

Usefulness of the Stroop Test in Diagnosing Minimal Hepatic Encephalopathy and Predicting Overt Hepatic Encephalopathy

Minimal hepatic encephalopathy (MHE) adversely affects the clinical outcomes of patients with liver cirrhosis. This prospective study aimed to evaluate the utility of the Stroop test in the diagnosis of MHE and prediction of overt hepatic encephalopathy (OHE) in Japanese patients with cirrhosis. We enrolled 152 patients who underwent the Stroop test between November 2018 and February 2020. MHE was diagnosed using a combination of neuropsychological tests as the gold standard. The enrolled patients were followed up prospectively until the occurrence of OHE or August 2020. The optimal cutoff value of the Stroop test measurements was determined by receiver operating characteristic (ROC) curve analysis, and its predictive ability was assessed using the area under the ROC curve (AUC). Among the 139 eligible patients, 50 (36%) were diagnosed with MHE. The OffTime+OnTime cutoff value of 218.3 seconds had the best discriminative ability for MHE diagnosis, with an AUC of 0.77, a sensitivity of 74%, and a specificity of 75%. During a median follow-up of 10.8 months, 6 (4%) patients developed OHE. The OffTime+OnTime cutoff value of 305.6 seconds had the highest predictive ability for OHE, with an AUC of 0.79, a sensitivity of 67%, and a specificity of 92%. This value predicted OHE occurrence independent of liver functional reserve and prior OHE (hazard ratio, 19.8; P = 0.003). These two cutoff values remained statistically significant even when patients with prior OHE were excluded from the analysis. Conclusion: The Stroop test was useful for diagnosing patients with MHE and predicting OHE in Japanese patients with cirrhosis.

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.

Cognition-tracking-based strategies for diagnosis and treatment of minimal hepatic encephalopathy

Minimal hepatic encephalopathy (MHE), which shows mild cognitive impairment, is a subtle complication of cirrhosis that has been shown to affect daily functioning and quality of life. However, until 2014, relevant guidelines do not give much attention to the diagnosis and treatment of MHE, resulting in patients being ignored and denied the benefits of treatment. In this review, we summarize recent cognition-based research about (1) alteration of nerve cells, including astrocytes, microglial cells and neurons, in mild cognitive impairment in MHE; (2) comparison of methods in detecting cognitive impairment in MHE; and (3) comparison of methods for therapy of cognitive impairment in MHE. We hope to provide information about diagnosis and treatment of cognitive impairment in patients with MHE.

Combined Scores from the EncephalApp Stroop Test, Number Connection Test B, and Serial Dotting Test Accurately Identify Patients With Covert Hepatic Encephalopathy

BACKGROUND & AIMS

The EncephalApp Stroop test is a high-sensitivity but low-specificity test that has been used to identify patients with covert hepatic encephalopathy (CHE). We aimed to develop a new strategy to detect CHE, combining EncephalApp Stroop test score with scores from subtests of the psychometric hepatic encephalopathy scoring system (PHES).

METHODS

We performed a survey of 569 adult volunteers (229 men) in 9 communities in Shanghai, China, administering the EncephalApp Stroop test to determine the range of scores in the general population. Data from the standard PHES, including the number connection test-A, number connection test-B (NCT-B), line tracing test, serial dotting test (SDT), and digit symbol test, were used as the reference standard for diagnosis of CHE. A combination of the EncephalApp Stroop with subtests of the PHES was used to establish a new strategy for CHE diagnosis. We validated our findings using data from 160 patients with cirrhosis from 5 centers China.

RESULTS

We determined the range of EncephalApp Stroop test scores for the volunteers of different decades of age, education levels, and sexes. Age, education level, and sex were independently associated with EncephalApp Stroop test scores. A combination of scores from the EncephalApp Stroop test, the NCT-B, and the SDT identified patients with CHE with the highest level of accuracy, when the standard PHES was used as the reference standard. A combination of scores of 187 sec for the EncephalApp Stroop test and below -1 for the NCT-B or below -1 for the SDT identified patients with CHE with an area under the curve (AUC) of 0.86, 81.0% sensitivity, and 91.9% specificity, and 87.5% accuracy. In the validation cohort, these cutoff scores identified patients with CHE with an AUC of 0.88, 97.1% sensitivity, 79.3% specificity, and 86.9% accuracy. The average time to calculate this score was 374±140 sec, compared 424±115 sec for the entire PHES.

CONCLUSION

Scores from the EncephalApp Stroop test, NCT-B, and SDT identify patients with CHE with approximately 87% accuracy, and in a much shorter time than the standard PHES. This score combination could be a valid and convenient method for identifying patients with CHE. chictr.org.cn number, ChiCTR-EDC-17012007, ChiCTR1800019954.