Diagnosis of sub-clinical hepatic encephalopathy by Neuropsychological Tests (NP-tests)

A simple covert hepatic encephalopathy screening model based on blood biochemical parameters in patients with cirrhosis

AIM

Covert hepatic encephalopathy (CHE) adversely affects clinical outcomes in patients with liver cirrhosis, although its diagnosis is difficult. This study aimed to establish a simple CHE screening model based on blood-related biochemical parameters.

METHODS

This retrospective study enrolled 439 patients who were assessed for CHE using a neuropsychiatric test between January 2011 and June 2019. A simple CHE (sCHE) score was calculated with hypoalbuminemia (≤ 3.5 g/dL) and hyperammonemia (≥ 80 μg/dL) as 1 point each. The association between sCHE score and CHE or overt hepatic encephalopathy (OHE) was assessed using logistic regression and Fine-Gray competing risk regression models.

RESULTS

Of 381 eligible patients, 79 (21%) were diagnosed with CHE. The distribution of sCHE scores was 48% with 0 point, 33% with 1 point, and 19% with 2 points. Patients with sCHE score ≥ 1 point had a higher prevalence of CHE than those with sCHE score of 0 (27% vs. 14%, P = 0.002). A cut-off value of 1 point showed high discriminative ability for identifying CHE, with a sensitivity of 0.67, specificity of 0.56, positive predictive value of 0.27, and negative predictive value of 0.86. During the median follow-up period of 2.2 years, 58 (15%) patients developed OHE. Multivariate analysis showed that sCHE score ≥ 1 (sub-distribution hazard ratio [SHR], 2.69; 95% confidence interval [CI], 1.41-5.15) and CHE (SHR, 2.17; 95% CI, 1.26-3.73) independently predicted OHE.

CONCLUSIONS

The sCHE score is a useful screening model for identifying patients with CHE and for predicting OHE occurrence.

Hydrogen-producing small intestinal bacterial overgrowth is associated with hepatic encephalopathy and liver function

Overt hepatic encephalopathy (HE) is one of the complications of liver cirrhosis (LC), which negatively affects the prognosis and quality of life of patients. Small intestinal bacterial overgrowth (SIBO) is significantly associated with LC and its complications, including HE. We investigated the relationship between SIBO and LC, and the difference between hydrogen-producing and methane-producing SIBO (H-SIBO and M-SIBO, respectively). This is a prospective cohort study of 107 cases. Breath measurements of hydrogen and methane concentrations were performed for the diagnosis of SIBO. The study cohort included 81 males with a median age of 70 (40–86) years, and SIBO was detected in 31 cases (29.0%). There were no significant differences between the SIBO positive and SIBO negative groups. Reclassification into H-SIBO (16 cases) and others (91 cases) was performed, and the Child-Pugh score was only derived in the multivariate logistic analysis (P = 0.028, odds ratio 1.39, 95% confidence interval 1.04–1.85). Furthermore, H-SIBO was significantly associated with covert HE in chi-square test (50.0% vs. 24.2%, P = 0.034). In addition, we evaluated the therapeutic response on SIBO of rifaximin in eight covert HE patients. 20% patients with M-SIBO and 67% patients with H-SIBO showed an improvement of the breath test. In conclusion, H-SIBO, but not M-SIBO, is significantly associated with liver function, and rifaximin might be more effective for covert HE with H-SIBO. Therefore, the diagnosis of SIBO, including the classification as H-SIBO and M-SIBO, might help to determine the choice of treatment for HE.

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.

Impaired brain function improved by L-carnitine in patients with cirrhosis: evaluation using near-infrared spectroscopy

To evaluate the effects of l-carnitine on impaired brain function in patients with liver cirrhosis. We conducted a retrospective cohort study that included sequential 80 liver cirrhosis patients with impaired brain function evaluated using near-infrared spectroscopy (NIRS). Among them, l-carnitine was administered to 48 patients. The NIRS data and blood ammonia level at baseline and after 8 weeks of treatment were compared between patients administered with l-carnitine (l-carnitine group) and those who were not (control group). The NIRS data at baseline were similar between the l-carnitine and control groups (0.04 ± 0.04 vs. 0.04 ± 0.05 mMmm, p = n.s), whereas those in the l-carnitine group (n = 48) were significantly better than that of the control group at 8 weeks of treatment (n = 32) (0.103 ± 0.081 vs. 0.040 ± 0.048 mMmm, p < 0.001). In the l-carnitine group, 35.4% (17/48) of patients had hyperammonemia. The NIRS data of the l-carnitine group at 8 weeks of treatment were significantly improved than that of the control group, irrespective of baseline ammonia levels (0.11 ± 0.09 vs. 0.04 ± 0.05 mMmm, p = 0.005, and 0.10 ± 0.06 vs. 0.02 ± 0.03 mMmm, p = 0.003, for normal baseline ammonia and elevated ammonia levels, respectively). In the multivariate analysis, l-carnitine administration (odds ratio [OR] 3.51, 95% confidence interval [CI] 1.23–9.99, p = 0.019) and baseline NIRS data of ≤ 0.07 mMmm (OR 5.21, 95% CI 1.69–16.0, p = 0.0041) were found as independent significant factors. l-carnitine improves impaired brain function in patients with liver cirrhosis.

Prognostic significance of minimal hepatic encephalopathy in patients with liver cirrhosis in Japan: A propensity score-matching analysis

BACKGROUND AND AIM

Minimal hepatic encephalopathy (MHE) represents the mildest form of the hepatic encephalopathy spectrum. This study aimed to clarify the prognostic significance of MHE in cirrhotic patients.

METHODS

This retrospective study evaluated 357 consecutive patients with liver cirrhosis. MHE was diagnosed using a neuropsychiatric test. A propensity score-matching analysis was employed to adjust significant differences in the baseline characteristics between patients with and without MHE.

RESULTS

Of 269 eligible patients, 56 patients (21%) were diagnosed as having MHE. The Child-Pugh score, model for end-stage liver disease score, and serum ammonia levels were significantly increased, while serum albumin levels were reduced in patients with MHE. By contrast, no significant difference was found between the two groups in matched patients. During the median follow-up period of 13.4 months, 67 patients (24.9%) died. Overall survival rates were significantly lower in patients with MHE (median, 25.4 vs 48.8 months; P < 0.001). Multivariate analysis revealed that male sex (hazard ratio [HR], 1.78; 95% confidence interval [CI], 1.03-3.18; P = 0.038), stage III/IV hepatocellular carcinoma (HR, 6.32; 95% CI, 3.30-12.79; P < 0.001), the Child-Pugh score (HR, 1.35; 95% CI, 1.12-1.62; P = 0.002), and MHE (HR, 1.92; 95% CI, 1.09-3.29; P = 0.024) were independently associated with mortality in all patients as well as in matched patients.

CONCLUSION

Minimal hepatic encephalopathy is associated with an increased risk of mortality in patients with liver cirrhosis, independent of hepatocellular carcinoma stage or Child-Pugh score.

Sarcopenia predicts minimal hepatic encephalopathy in patients with liver cirrhosis

AIM

Minimal hepatic encephalopathy (MHE) and sarcopenia impair the health-related quality of life and prognosis of patients with liver cirrhosis; however, the relationship between MHE and sarcopenia remains unclear. The aim of this study was to investigate their relationship and to identify the predictors of MHE in cirrhotic patients.

METHODS

This retrospective study evaluated 120 cirrhotic patients who were tested for MHE and sarcopenia. Minimal hepatic encephalopathy was diagnosed by using the computer-aided neuropsychiatric test. Sarcopenia was diagnosed based on the assessment criteria recommended by the Japan Society of Hepatology. Muscle mass and muscle strength were measured by using bio-impedance analysis and digital grip strength dynamometer. Univariate and multivariate logistic regression analyses were carried out to identify the predictors of MHE.

RESULTS

Of the 120 cirrhotic patients, 28 (23%) and 32 (27%) were diagnosed with MHE and sarcopenia, respectively. The prevalence of MHE was higher in patients with sarcopenia than in those without sarcopenia (P = 0.01). By the univariate analysis, MHE was significantly complicated with sarcopenia (P < 0.01). In the multivariate analysis, sarcopenia (odds ratio = 3.31, 95% confidence interval = 1.19-9.42; P = 0.02) and serum branched-chain amino acids levels <327 nmol/mL (odds ratio = 2.98, 95% confidence interval = 1.08-8.34; P = 0.03) were found to be associated with MHE.

CONCLUSIONS

Sarcopenia and serum branched-chain amino acids levels were predictors of MHE. The amelioration of sarcopenia and/or amino acids imbalance may improve MHE in patients with liver cirrhosis.

Screening for minimal hepatic encephalopathy in patients with cirrhosis by cirrhosis-related symptoms and a history of overt hepatic encephalopathy

The diagnosis of minimal hepatic encephalopathy (MHE) is more difficult in comparison to the diagnosis of overt hepatic encephalopathy (OHE), as patients with MHE do not exhibit overt neurological deficits and must be diagnosed using specialized equipment. However, identifying MHE is critical for patients with cirrhosis, and a simple screening test is required. The present study aimed to evaluate the associations between MHE, clinical characteristics and questionnaire items regarding sleep disturbances and cirrhosis-related symptom score (CSS). A total of 91 patients who had cirrhosis without OHE were evaluated using various questionnaires [i.e., CSS, Epworth Sleepiness Scale, the Japanese version of the Pittsburgh Sleep Quality Index (PSQI) and the Japanese 36-item short-form health survey (SF-36)]. MHE was diagnosed using the neuropsychological test. MHE was associated with severe liver damage, which was indicated by liver damage markers and a history of OHE. In addition, MHE was associated with the CSS, PSQI and SF-36 results. The multivariate analyses revealed that a history of OHE was the factor that was the most strongly associated with MHE. Among patients without a history of OHE, MHE was most strongly associated with CSS, although it was also associated with severe liver damage and platelet counts. A prediction score (calculated using a history of OHE and CSS) provided an area under the receiver operating characteristic curve of 0.738 and a sensitivity of 0.671 for identifying MHE. In conclusion, a history of OHE and CSS may be useful for identifying MHE in patients with cirrhosis.

Diagnosing and treating hepatic encephalopathy

Hepatic encephalopathy is a complex condition. This article considers the efficacy of the methods used in its diagnosis and management and discusses the impact of minimal hepatic encephalopathy on patients and the ethics of its treatment.

Impaired brain activity in cirrhotic patients with minimal hepatic encephalopathy: Evaluation by near-infrared spectroscopy

AIM

Near-infrared spectroscopy (NIRS) is a tool that could non-invasively measure the regional cerebral oxygenated hemoglobin (oxy-Hb) concentration with high time resolution. The aim of the present study is to reveal the time-dependent regional cerebral oxy-Hb concentration change coupled with brain activity during task performance in patients with minimal hepatic encephalopathy (MHE).

METHODS

Cerebral oxy-Hb concentration was measured by using NIRS in 29 cirrhotic patients without overt hepatic encephalopathy (HE). Of those, 16 patients who had abnormal electroencephalography findings were defined as having MHE. Responsive increase in oxy-Hb during a word-fluency task was compared between MHE and non-MHE patients.

RESULTS

There was no difference in the maximum value of oxy-Hb increase between patients with and without MHE (0.26 ± 0.12 vs 0.32 ± 0.22 mM·mm, P = 0.37). However, the pattern of the time course changes of oxy-Hb was different between the two groups. The MHE group was characterized by a gradual increase of oxy-Hb throughout the task compared to steep and repetitive increase in the non-MHE group. Increase in oxy-Hb concentration at 5 s after starting the task was significantly small in the MHE group compared to the non-MHE (0.03 ± 0.05 vs 0.11 ± 0.09 mM·mm, P = 0.006).

CONCLUSION

The cerebral oxygen concentration is poorly reactive in response to tasks among cirrhotic patients without overt HE but having abnormal electroencephalography findings. These impaired responses in regional cerebral oxy-Hb concentration may be related to the latent impairment of brain activity seen in MHE.

Effects of oral branched-chain amino acids on hepatic encephalopathy and outcome in patients with liver cirrhosis

Branched-chain amino acids (BCAAs) constituting of valine, leucine, and isoleucine act as both substrates of proteins and as key regulators for various nutrient metabolisms. Patients with liver cirrhosis frequently lack sufficient BCAAs and therefore suffer from various metabolic disorders. Hepatic encephalopathy (HE) is a severe metabolic disorder with neurologic manifestations such as flapping tremors and coma in patients with liver cirrhosis. In addition, a mild form of HE known as minimal HE (MHE) is an important social issue because it occurs in up to 80% of patients with chronic liver disease and affects prognosis and activities of daily living, possibly resulting in falls and motor vehicle accidents. Although HE/MHE can be caused by various pathological conditions, including in an accumulation of mercaptans, short-chain fatty acids, and alterations in the gut flora, hyperammonemia has also been implicated in an important pathogenesis of HE/MHE. Besides urea cycle of liver, ammonia can be detoxified in the skeletal muscles by the amidation process for glutamine synthesis using BCAAs. Thus, BCAA supplementation may enhance detoxification of ammonia in skeletal muscle and may be a possible therapeutic strategy for HE/MHE. In this review, we summarize the clinical impacts of BCAA supplementation on HE/MHE and discuss possible mechanisms for a BCAA-induced improvement of HE/MHE. Furthermore, we present some modifications of oral BCAA therapy for improvement of efficacy in HE treatment. We also briefly describe pleiotropic benefits of BCAAs on life-threatening events and overall prognosis in patients with liver cirrhosis.

Lipid profile is associated with the incidence of cognitive dysfunction in viral cirrhotic patients: A data-mining analysis

AIM

  Cognitive dysfunction (CD) is frequently observed in cirrhotic patients. However, the biochemical profiles associated with CD remain unclear. We investigated the biochemical profiles associated with the incidence of CD in cirrhotic patients by using multivariate analyses, including a decision-tree algorithm.

METHODS

  In this study, 27 viral cirrhotic patients were enrolled. All subjects underwent neuropsychiatric tests; two or more abnormal results were defined as CD. A logistic regression model was used for multivariate stepwise analysis. A decision-tree algorithm was constructed, and the categorical differences based on the decision-tree model were analyzed by χ(2) -tests.

RESULTS

  Multivariate stepwise analysis showed the levels of total bilirubin, triglycerides and free fatty acids (FFA) as independent bioparameters associated with the incidence of CD in cirrhotic patients. The decision-tree algorithm showed that among patients with FFA of 514 mEq/L or more, 77.8% had CD. Meanwhile, among patients with FFA of less than 514 mEq/L and triglycerides of 106 mg/dL or more, 20.0% had CD. The sensitivity, specificity and accuracy for the incidence of CD using the lipid profile (FFA >514 mEq/L or triglycerides <106 mg/dL) were 85.7% (12/14), 61.5% (8/13) and 74.1% (20/27), respectively.

CONCLUSION

  The levels of total bilirubin, FFA and triglycerides are independently associated with the incidence of CD in cirrhotic patients. In addition, a decision-tree algorithm revealed that FFA of more than 514 mEq/L or triglycerides of less than 106 mg/dL is a profile associated with the incidence of CD. Thus, this lipid profile could be a possible screening bioparameter for CD in cirrhotic patients.