Rifaximin improves psychometric performance and health-related quality of life in patients with minimal hepatic encephalopathy (the RIME Trial)

Meta-analysis: The diagnostic accuracy of critical flicker frequency in minimal hepatic encephalopathy

BACKGROUND

Minimal hepatic encephalopathy (MHE) reduces quality of life, increases the risk of road traffic incidents and predicts progression to overt hepatic encephalopathy and death. Current psychometry-based diagnostic methods are effective, but time-consuming and a universal 'gold standard' test has yet to be agreed upon. Critical Flicker Frequency (CFF) is a proposed language-independent diagnostic tool for MHE, but its accuracy has yet to be confirmed.

AIM

To assess the diagnostic accuracy of CFF for MHE by performing a systematic review and meta-analysis of all studies, which report on the diagnostic accuracy of this test.

METHODS

A systematic literature search was performed to locate all publications reporting on the diagnostic accuracy of CFF for MHE. Data were extracted from 2 × 2 tables or calculated from reported accuracy data. Collated data were meta-analysed for sensitivity, specificity, diagnostic odds ratio (DOR) and summary receiver operator curve (sROC) analysis. Prespecified subgroup analysis and meta-regression were also performed.

RESULTS

Nine studies with data for 622 patients were included. Summary sensitivity was 61% (95% CI: 55-67), specificity 79% (95% CI: 75-83) and DOR 10.9 (95% CI: 4.2-28.3). A symmetrical sROC gave an area under the receiver operator curve of 0.84 (SE = 0.06). The heterogeneity of the DOR was 74%.

CONCLUSIONS

Critical Flicker Frequency has a high specificity and moderate sensitivity for diagnosing minimal hepatic encephalopathy. Given the advantages of language independence and being both simple to perform and interpret, we suggest the use of critical flicker frequency as an adjunct (but not replacement) to psychometric testing.

Treatment with a potassium-iron-phosphate-citrate complex improves PSE scores and quality of life in patients with minimal hepatic encephalopathy: a multicenter, randomized, placebo-controlled, double-blind clinical trial

OBJECTIVE

Minimal hepatic encephalopathy (MHE) is one of the possible complications of liver cirrhosis. In this study, a potassium-iron-phosphate-citrate complex was analyzed for its efficacy and safety in the treatment of MHE, as this complex is supposed to bind to the major pathogenic factor of MHE: intestinal ammonia.

MATERIALS AND METHODS

In this placebo-controlled, double-blind clinical trial, 51 patients with MHE were randomized into two groups at a ratio of 1 : 1 and treated for 4 weeks either with a potassium-iron-phosphate-citrate complex or a placebo. The efficacy of treatment was assessed according to changes in the portosystemic encephalopathy (PSE) score. Further assessments included alterations in quality of life and safety evaluations.

RESULTS

Significantly more patients showed improvements in the PSE syndrome test from pathological to nonpathological PSE scores in the potassium-iron-phosphate-citrate-treated group (72.0%) than in the placebo group (26.9%; P=0.0014). Furthermore, quality of life improved at a higher grade in the verum group (by 0.7 ± 0.6 U) compared with the placebo group (by 0.2 ± 0.6 U; P=0.0036). Adverse events occurring in 28.0% of potassium-iron-phosphate-citrate-treated patients were generally mild or moderate and affected mainly the gastrointestinal tract.

CONCLUSION

Treatment with potassium-iron-phosphate-citrate significantly improved PSE scores and quality of life in patients with MHE. The potassium-iron-phosphate-citrate complex is a well-tolerated treatment option in MHE.

The conservative and interventional treatment of the complications of liver cirrhosis: Part 2 of a series on liver cirrhosis

BACKGROUND

It is estimated that 1 million persons in Germany suffer from hepatic cirrhosis, which is the final stage of chronic inflammation of the liver. Cirrhosis has multiple causes, all of which lead to structural changes of the liver and to portal hypertension. The main complications of cirrhosis arise in turn: These include bleeding from collateral veins, ascites, hepatocellular carcinoma, encephalopathy, and infection leading to organ failure.

METHODS

We present the treatment of the main complications of liver cirrhosis with reference to the relevant literature (phase II and III trials, meta-analyses, and reviews).

RESULTS

Endoscopic treatment (ligation) is used for the primary and secondary prophylaxis of variceal bleeding. Drugs to lower portal pressure (e.g., beta-blockers) are an established means of preventing initial or recurrent variceal bleeding over the long term. Vasoconstrictors such as terlipressin are mainly used to treat acute hemorrhage and type 1 hepatorenal syndrome. The main treatment of ascites is with spironolactone, in combination with a loop diuretic where indicated. A shunt (TIPS) is used to treat severe or repeat variceal hemorrhage or refractory ascites. Antibiotics play a well-established role in the treatment of acute hemorrhage, in the treatment and prevention of spontaneous bacterial peritonitis, and in the treatment of encephalopathy. The treatment of hepatocellular carcinoma depends on its extent of spread and on the degree of decompensation of cirrhosis.

CONCLUSION

For most of the main complications of liver cirrhosis, there are treatments that have been well-tested in randomized trials. Liver transplantation should also be considered in every case.

Altered effective connectivity network of the basal ganglia in low-grade hepatic encephalopathy: a resting-state fMRI study with Granger causality analysis

Background

The basal ganglia often show abnormal metabolism and intracranial hemodynamics in cirrhotic patients with hepatic encephalopathy (HE). Little is known about how the basal ganglia affect other brain system and is affected by other brain regions in HE. The purpose of this study was to investigate whether the effective connectivity network associated with the basal ganglia is disturbed in HE patients by using resting-state functional magnetic resonance imaging (rs-fMRI).

Methodology/Principal Findings

Thirty five low-grade HE patients and thirty five age- and gender- matched healthy controls participated in the rs-fMRI scans. The effective connectivity networks associated with the globus pallidus, the primarily affected region within basal ganglia in HE, were characterized by using the Granger causality analysis and compared between HE patients and healthy controls. Pearson correlation analysis was performed between the abnormal effective connectivity and venous blood ammonia levels and neuropsychological performances of all HE patients. Compared with the healthy controls, patients with low-grade HE demonstrated mutually decreased influence between the globus pallidus and the anterior cingulate cortex (ACC), cuneus, bi-directionally increased influence between the globus pallidus and the precuneus, and either decreased or increased influence from and to the globus pallidus in many other frontal, temporal, parietal gyri, and cerebellum. Pearson correlation analyses revealed that the blood ammonia levels in HE patients negatively correlated with effective connectivity from the globus pallidus to ACC, and positively correlated with that from the globus pallidus to precuneus; and the number connectivity test scores in patients negatively correlated with the effective connectivity from the globus pallidus to ACC, and from superior frontal gyrus to globus pallidus.

Conclusions/Significance

Low-grade HE patients had disrupted effective connectivity network of basal ganglia. Our findings may help to understand the neurophysiological mechanisms underlying the HE.

Pathological bacterial translocation in cirrhosis: pathophysiology, diagnosis and clinical implications

Bacterial translocation (BT) is defined by the passage of viable indigenous bacteria from the intestinal lumen to mesenteric lymph nodes (MLNs) and other territories, and its diagnostic criteria rely on the isolation of viable bacteria in MLNs. Small intestinal overgrowth, increased intestinal permeability and immunological alterations are the main factors involved in its pathogenesis. BT is obviously difficult to identify in patients with cirrhosis, and alternative methods have been proposed instead. Bacterial DNA detection and species identification in serum or ascitic fluid has been proposed as a reliable marker of BT. Bacterial products, such as endotoxin, or bacterial DNA can translocate to extra-intestinal sites and promote an immunological response similar to that produced by viable bacteria. Therefore, pathological BT plays an important role in the pathogenesis of the complications of cirrhosis, not only in infections, but by exerting a profound inflammatory state and exacerbating the haemodynamic derangement. This may promote in turn the development of hepatorenal syndrome, hepatic encephalopathy and other portal hypertension-related complications. Therapeutic approaches for the prevention of BT in experimental and human cirrhosis are summarized. Finally, new investigations are needed to better understand the pathogenesis and consequences of translocation by viable bacteria (able to grow in culture), or non-viable BT (detection of bacterial fragments with negative culture) and open new therapeutic avenues in patients with cirrhosis.

Impact of pretransplant hepatic encephalopathy on liver posttransplantation outcomes

Patients with cirrhosis commonly experience hepatic encephalopathy (HE), a condition associated with alterations in behavior, cognitive function, consciousness, and neuromuscular function of varying severity. HE occurring before liver transplant can have a substantial negative impact on posttransplant outcomes, and preoperative history of HE may be a predictor of posttransplant neurologic complications. Even with resolution of previous episodes of overt or minimal HE, some patients continue to experience cognitive deficits after transplant. Because HE is one of the most frequent pretransplant complications, improving patient HE status before transplant may improve outcomes. Current pharmacologic therapies for HE, whether for the treatment of minimal or overt HE or for prevention of HE relapse, are primarily directed at reducing cerebral exposure to systemic levels of gut-derived toxins (e.g., ammonia). The current mainstays of HE therapy are nonabsorbable disaccharides and antibiotics. The various impacts of adverse effects (such as diarrhea, abdominal distention, and dehydration) on patient's health and nutritional status should be taken into consideration when deciding the most appropriate HE management strategy in patients awaiting liver transplant. This paper reviews the potential consequences of pretransplant HE on posttransplant outcomes and therapeutic strategies for the pretransplant management of HE.

The intestinal microbiota in chronic liver disease

Recent evidence indicates that the intestinal microflora plays a critical role in physiological and pathological processes; in particular, it is now considered a key determinant of immune pathologies and metabolic syndrome. Receiving the majority of its blood supply from the portal vein, the liver represents the first line of defense against food antigens, toxins, microbial-derived products, and microorganisms. Moreover, the liver is critically positioned to integrate metabolic outcomes with nutrient intake. To accomplish this function, the liver is equipped with a broad array of immune networks. It is now evident that, during pathological processes associated with obesity, alcohol-intake, or autoimmunity, the interaction between these immune cell populations and the intestinal microbiota promotes chronic liver disease progression and therefore they represent a novel therapeutic target. Herein, we highlight recent studies that have shed new light on the relationship between the microbiome, the innate immune system, and chronic liver disease progression.

Prevention and treatment of hepatic encephalopathy: focusing on gut microbiota

The gut flora plays an important role in the pathogenesis of the complications of cirrhosis. Hepatic encephalopathy (HE) represents a broad continuum of neuropsychological dysfunction in patients with acute or chronic liver disease and/or porto-systemic shunting of blood flow and it manifests with progressive deterioration of the superior neurological functions. The pathophysiology of this disease is complex, as it involves overproduction and reduced metabolism of various neurotoxins, particularly ammonia. Management of HE is diversified and requires several steps: elimination of precipitating factors, removal of toxins, proper nutritional support, modulation of resident fecal flora and downregulation of systemic and gut-derived inflammation. This review will provide an overview of gut barrier function and the influence of gut-derived factors on HE, focusing on the role of gut microbiota in the pathogenesis of HE and the recent literature findings on its therapeutic manipulation.

Factors related to quality of life in patients with cirrhosis and ascites: relevance of serum sodium concentration and leg edema

BACKGROUND & AIMS

Hyponatremia is common in patients with cirrhosis and ascites and is associated with significant neurological disturbances. However, its potential effect on health-related quality of life (HRQL) in cirrhosis has not been investigated. We aimed at assessing the relationship between serum sodium concentration and other clinical and analytical parameters on HRQL in cirrhosis with ascites.

METHODS

A total of 523 patients with cirrhosis and ascites were prospectively investigated. Assessment of HRQL was done with the Medical Outcomes Study Short-Form 36 (SF-36) questionnaire, which is divided into 8 domains, summarized in two components: physical component score (PCS) and mental component score (MCS). Demographic, clinical, and analytical data at baseline were analyzed for their relationship with HRQL.

RESULTS

In multivariate analysis, independent predictive factors associated with an impaired PCS were non-alcoholic etiology of cirrhosis, severe ascites, history of previous episodes of hepatic encephalopathy and falls, presence of leg edema, and low serum sodium concentration. With respect to MCS, only two factors were associated with the independent predictive value: low serum sodium concentration and treatment with lactulose or lactitol. In both components, the scores decreased in parallel with the reduction in serum sodium concentration. Variables more commonly associated with the independent predictive value in the individual 8 domains of PCS and MCS were presence of leg edema and serum sodium concentration, 7 and 6 domains, respectively.

CONCLUSIONS

Serum sodium concentration and presence of leg edema are major factors of the impaired HRQL in patients with cirrhosis and ascites.

Gender and age effects on the continuous reaction times method in volunteers and patients with cirrhosis

Minimal hepatic encephalopathy (MHE) is a metabolic brain disorder occurring in patients with liver cirrhosis. MHE lessens a patient's quality of life, but is treatable when identified. The continuous reaction times (CRT) method is used in screening for MHE. Gender and age effects on the CRT method are unknown and may confound the results. The aim of this study was to standardise the CRT method outcomes for age and gender effects. We studied 121 volunteers without known disease and 181 patients with cirrhosis by a CRT test. Reaction time to an auditory signal was measured 100 times, the 10th, 50th, and 90th reaction time percentiles were recorded, and the CRT index was calculated as the 50th percentile/(90th percentile-10th percentile), as a measure of intra-individual stability in reaction times. In volunteers, men reacted faster than women and their reaction times slowed with age. However, neither the gender nor the age effect was present regarding the CRT index. The patients with cirrhosis reacted slower and with a higher degree of instability than volunteers. Male patients reacted faster than female patients, and reaction times tended to slow with age. As among the volunteers, there was no gender or age effect on CRT index for the patients with cirrhosis. Age and gender influenced reaction times of both volunteers and patients with cirrhosis. The CRT index, however, was independent of age and gender in both groups. Screening of patients with cirrhosis using the CRT index, therefore, identifies brain dysfunction rather than effects of gender and age.

Inhibitory control test for the detection of minimal hepatic encephalopathy in patients with cirrhosis of liver

BACKGROUND & AIMS

Minimal hepatic encephalopathy (MHE) has significant impact on future clinical outcomes, such as occurrence of overt HE (OHE) and survival in patients of cirrhosis. In the absence of a 'gold standard', psychometric hepatic encephalopathy score (PHES) is widely used for the diagnosis of MHE. This cross-sectional and prospective study was carried out to determine the usefulness of inhibitory control test (ICT) for the diagnosis of MHE.

METHODS

One hundred and two patients with cirrhosis and without a history of OHE were enrolled in to the study and were subjected to PHES and ICT. MHE was diagnosed when the PHES was ≤ -5. ICT was considered abnormal when the numbers of ICT lures were more than 14.

RESULTS

Forty-one (40.2%) patients had MHE. There were 40 patients with normal PHES and ICT, 32 with abnormal PHES and ICT, 9 with abnormal PHES and normal ICT, and 21 with abnormal ICT and normal PHES score. ICT had 78% sensitivity and 65.6% specificity and an area-under-the-curve value of 0.735 (95% CI = 0.632-0.830) for the diagnosis of MHE. In patients with cirrhosis, ICT did not correlate with severity of liver disease as measured by CTP score (r = 0.044, P = 0.658) and MELD score (r = 0.176, P = 0.077). ICT did not predict survival as well as PHES; while 6 (11.3%) patients died among those who had altered ICT compared to 4 (8.2%) patients who did not have altered ICT (P = 0.74), 8 (19.5%) patients died among those who had altered PHES compared to 2 (3.3%) patients who did not have altered PHES (P = 0.013).

CONCLUSION

ICT is not as useful as PHES in diagnosing MHE in patients with cirrhosis of the liver. It does not correlate with disease severity and predict survival as well as PHES.

New therapeutic paradigm for patients with cirrhosis

Cirrhosis is a major health problem, being the 5th cause of death in the U.K. and 12th in the U.S., but 4th in the 45 to 54 age group. Until recently cirrhosis was considered a single and terminal disease stage, with an inevitably poor prognosis. However, it is now clear that 1-year mortality can range from 1% in early cirrhosis to 57% in decompensated disease. As the only treatment for advanced cirrhosis is liver transplantation, what is urgently needed is strategies to prevent transition to decompensated stages. The evidence we present in this review clearly demonstrates that management of patients with cirrhosis should change from an expectant algorithm that treats complications as they occur, to preventing the advent of all complications while in the compensated phase. This requires maintaining patients in an asymptomatic phase and not significantly affecting their quality of life with minimal impairment due to the therapies themselves. This could be achieved with lifestyle changes and combinations of already licensed and low-cost drugs, similar to the paradigm of treating risk factors for cardiovascular disease. The drugs are propranolol, simvastatin, norfloxacin, and warfarin, which in combination would cost £128/patient annually-equivalent to U.S. $196/year. This treatment strategy requires randomized controlled trials to establish improvements in outcomes. In the 21st century, cirrhosis should be regarded as a potentially treatable disease with currently available and inexpensive therapies.

Covert hepatic encephalopathy: not as minimal as you might think

Hepatic encephalopathy (HE) is a serious neuropsychiatric and neurocognitive complication of acute and chronic liver disease. Symptoms are often overt (confusion, disorientation, ataxia, or coma) but can also be subtle (difficulty with cognitive abilities such as executive decision-making and psychomotor speed). There is consensus that HE is characterized as a spectrum of neuropsychiatric symptoms in the absence of brain disease, ranging from overt HE (OHE) to minimal HE (MHE). The West Haven Criteria are most often used to grade HE, with scores ranging from 0-4 (4 being coma). However, it is a challenge to diagnose patients with MHE or grade 1 HE; it might be practical to combine these entities and name them covert HE for clinical use. The severity of HE is associated with the stage of liver disease. Although the pathologic mechanisms of HE are not well understood, they are believed to involve increased levels of ammonia and inflammation, which lead to low-grade cerebral edema. A diagnosis of MHE requires dedicated psychometric tests and neurophysiological techniques rather than a simple clinical assessment. Although these tests can be difficult to perform in practice, they are cost effective and important; the disorder affects patients' quality of life, socioeconomic status, and driving ability and increases their risk for falls and the development of OHE. Patients with MHE are first managed by excluding other causes of neurocognitive dysfunction. Therapy with gut-specific agents might be effective. We review management strategies and important areas of research for MHE and covert HE.

Rifaximin therapy and hepatic encephalopathy: Pros and cons

Hepatic encephalopathy (HE) is the second most common major complication in cirrhotics and it significantly impacts quality of life. Therapeutic approaches for HE treatment and prevention mainly continue to rely on ammonia-lowering strategies and non-absorbable disaccharides are currently considered the cornerstone therapy. Non-absorbable antibiotics, such as neomycin and paramomycin, are effective in treatment of acute HE episodes but their prolonged use for recurrence prevention is hampered by possible side-effects. To overcome these limitations, rifaximin use has been proposed. Rifaximin has been shown to be not superior to non-absorbable disaccharides for either HE treatment or prevention, with a similar incidence of side-effects. Cirrhosis significantly increases rifaximin absorption and this could be a cause for concern. Following long-term rifaximin therapy, Clostridium difficile colitis has been observed and Candida albicans has been isolated from 20% of patients. In addition, selection of resistant mutants of both Gram-negative and -positive bacteria in the gastrointestinal tract cannot be definitely ruled out. Electrolyte alterations (sodium and potassium) have been reported during rifaximin therapy, a warning for its long-term use in cirrhotics. Moreover, a potential interference with vitamin K production should be considered which could further impair the already altered clotting status of these patients. The therapeutic cost of rifaximin is markedly higher than non-absorbable disaccharides. While waiting for further safety data, caution should be used to limit the use of rifaximin therapy for a very short-term period in selected HE cirrhotics not responding to non-absorbable disaccharides.

Structural and functional abnormalities of default mode network in minimal hepatic encephalopathy: a study combining DTI and fMRI

Background and Purpose

Live failure can cause brain edema and aberrant brain function in cirrhotic patients. In particular, decreased functional connectivity within the brain default-mode network (DMN) has been recently reported in overt hepatic encephalopathy (HE) patients. However, so far, little is known about the connectivity among the DMN in the minimal HE (MHE), the mildest form of HE. Here, we combined diffusion tensor imaging (DTI) and resting-state functional MRI (rs-fMRI) to test our hypothesis that both structural and functional connectivity within the DMN were disturbed in MHE.

Materials and Methods

Twenty MHE patients and 20 healthy controls participated in the study. We explored the changes of structural (path length, tracts count, fractional anisotropy [FA] and mean diffusivity [MD] derived from DTI tractography) and functional (temporal correlation coefficient derived from rs-fMRI) connectivity of the DMN in MHE patients. Pearson correlation analysis was performed between the structural/functional indices and venous blood ammonia levels/neuropsychological tests scores of patients. All thresholds were set at P<0.05, Bonferroni corrected.

Results

Compared to the healthy controls, MHE patients showed both decreased FA and increased MD in the tract connecting the posterior cingulate cortex/precuneus (PCC/PCUN) to left parahippocampal gyrus (PHG), and decreased functional connectivity between the PCC/PCUN and left PHG, and medial prefrontal cortex (MPFC). MD values of the tract connecting PCC/PCUN to the left PHG positively correlated to the ammonia levels, the temporal correlation coefficients between the PCC/PCUN and the MPFC showed positive correlation to the digital symbol tests scores of patients.

Conclusion

MHE patients have both disturbed structural and functional connectivity within the DMN. The decreased functional connectivity was also detected between some regions without abnormal structural connectivity, suggesting that the former may be more sensitive in detecting the early abnormalities of MHE. This study extends our understanding of the pathophysiology of MHE.

Brain perfusion single photon emission computed tomography abnormalities in patients with minimal hepatic encephalopathy

BACKGROUND

Minimal hepatic encephalopathy (MHE) is the mildest form of hepatic encephalopathy (HE). Minimal hepatic encephalopathy patients do not demonstrate clinically overt symptoms of HE but present with abnormal neuropsychological and/or neurophysiological tests indicative of cerebral dysfunction. This study was performed in such patients to identify regions of abnormal cerebral perfusion and to correlate regional cerebral blood flow (rCBF) changes with psychometric hepatic encephalopathy score (PHES), Child-Turcotte-Pugh's score (CTP), and model for end-stage liver disease (MELD) score. We also compared abnormal patterns of rCBF in cirrhotic patients of alcoholic etiology with non-alcoholic etiology.

METHODS

This prospective study was performed to evaluate rCBF in 50 cirrhotic patients and 13 controls using technetium-99m ethyl cysteinate dimer (Tc-99m ECD) brain single photon emission computed tomography. All the patients underwent a battery of psychometry tests, PHES. Minimal hepatic encephalopathy was diagnosed if PHES was ≤-5. The rCBF changes were evaluated using region of interest (ROI) based semi-quantitative method of region/cerebellum and region/cortex ratios in 16 regions of the brain.

RESULTS

Cirrhotic patients with MHE showed impaired perfusion in the superior prefrontal cortex and increased perfusion in the thalamus, brain-stem, medial temporal cortex, and the hippocampus when compared with the controls. Cerebral perfusion in superior prefrontal cortex correlated negatively with MELD score (r=-0.323, P=0.022). We found significant positive correlation between PHES score and rCBF values in the left superior prefrontal cortex (r=0.385, P=0.006). Cirrhotic patients with alcohol etiology showed significantly decreased rCBF in right inferior prefrontal cortex, right superior prefrontal cortex, and the anterior cingulate cortex while increased rCBF was noted in the right medial temporal cortex and hippocampus.

CONCLUSION

Our results suggest that alterations in cognition in cirrhotic patients with MHE may be associated with impaired abnormalities of rCBF.

Hepatic encephalopathy

Hepatic encephalopathy (HE) represents a continuum of transient and reversible neurologic and psychiatric dysfunction. It is a reversible state of impaired cognitive function or altered consciousness in patients with liver disease or portosystemic shunting. Over the last several years, high-quality studies have been conducted on various pharmacologic therapies for HE; as more data emerge, it is hoped that HE will become a more easily treated complication of decompensated liver disease. In the interim, it is important that physicians continue to screen for minimal HE and treat patients early in addition to continuing to provide current treatments of overt HE.

Diagnosis and treatment of minimal hepatic encephalopathy to prevent motor vehicle accidents: a cost-effectiveness analysis

Minimal hepatic encephalopathy (MHE) in cirrhosis is associated with impaired driving skills and increased risk of motor vehicle accidents (MVAs). Detection and treatment of MHE has the potential to reduce costs and morbidity associated with MVAs. We conducted a cost-effectiveness analysis to assess the benefits of different strategies of MHE diagnosis and treatment for reducing MVA-related societal costs. The analyses compared five MHE management strategies: (1) presumptive treatment of all cirrhosis patients; (2) diagnosis by neuropsychological exam (NPE) with treatment; (3) diagnosis by standard psychometric tests (SPTs) with treatment; (4) diagnosis by rapid screening using inhibitory control test (ICT) with treatment; and (5) no MHE diagnosis or treatment (status quo). Treatments considered were lactulose or rifaximin, which were assumed to reduce the MVA rate to the level of similarly aged noncirrhosis patients with benefit adjusted for treatment compliance. A Markov model followed a simulated cohort of 1,000 cirrhosis patients without overt hepatic encephalopathy (OHE), from entry into treatment, through MHE development, and later OHE, when they exited the modeled cohort. Follow-up was for 5 years and included biannual MHE testing. The societal cost of a single MVA was estimated at $42,100. All four strategies with lactulose were cost-saving compared with the status quo. Diagnosis with ICT and lactulose was the most cost-effective approach (cost/MVA prevented: $24,454 ICT; $25,470 SPT; $30,469 presumptive treatment and $33,742 NPE). Net program savings over 5 years ranged from $1.7 to 3.6 million depending on the strategy. Rifaximin therapy was not cost-saving at current prices but would become so at a monthly cost of <$353.

CONCLUSION

Detection of MHE, especially using the ICT, and subsequent treatment with lactulose could substantially reduce societal costs by preventing MVAs.

The diagnosis and treatment of minimal hepatic encephalopathy

BACKGROUND

The subtype of hepatic encephalopathy (HE) called minimal hepatic encephalopathy (MHE) is highly prevalent (22-74%) among patients with liver dysfunction. MEH is defined as HE without grossly evident neurologic abnormalities, but with cognitive deficits that can be revealed by psychometric testing.

METHODS

This article is based on relevant original publications and reviews in English and German (1970-2011) that were retrieved by a selective key-word-based search in the Medline and PubMed databases.

RESULTS

Despite its mild manifestations, MHE impairs patients' quality of life and their ability to work. It impairs driving ability and is associated with a higher rate of motor vehicle accidents. Furthermore, patients with MHE fall more often and are more likely to undergo progression to overt HE. The main pathophysiological mechanism of MHE is hyperammonemia leading to astrocyte dysfunction. Psychometric tests are the standard instruments for establishing the diagnosis; further, supportive diagnostic tools include neurophysiological tests and imaging studies. Recent randomized and controlled trials have revealed that treatment with lactulose or rifaximin therapy improves the quality of life of patients with MHE. Rifaximin was also found to improve driving performance in a simulator. A combination of these two drugs prevents the recurrence of episodic HE over a 6-months follow-up period. Moreover, small-scale trials have revealed that some dietary supplements can improve the cognitive deficits of MHE.

CONCLUSION

Clinical trials have shown that patients with MHE and patients who have had an episode of overt HE in the past can benefit from drug treatment.

Management of covert hepatic encephalopathy

Employability, driving capacity, and many domains of health-related quality of life are reduced in patients with minimal hepatic encephalopathy (HE). Moreover, once minimal HE is identified, more than 50% of patients develop overt HE within 30 months. Now that minimal HE has been shown to be associated with consequences, more studies are needed to assess the cost effectiveness to treat it. This article discusses the issues regarding diagnosis and management of minimal HE, now called "Covert HE."

Driving simulation can improve insight into impaired driving skills in cirrhosis

BACKGROUND

Minimal hepatic encephalopathy (MHE) is associated with poor driving skills and insight. Increasing insight may improve receptiveness for therapy or driving restrictions.

AIM

To evaluate the change in the self-assessment of driving skills (SADS) using a driving simulator.

METHODS

Cirrhotic patients and age/education-matched controls underwent MHE testing with inhibitory control (ICT) and the psychometric hepatic encephalopathy score (PHES). SADS, a Likert scale from 0 to 10, was administered just before and after a standardized driving simulation comprising testing and navigation tasks. The percentage SADS change from baseline was compared within/between groups.

RESULTS

A total of 84 patients (60% men, age 55 years) and 12 controls were included. Controls were significantly better than cirrhotics on cognitive/simulator testing. The baseline SADS was similar between the groups. The baseline patient SADS was only correlated with ICT lures (r = -0.4, P = 0.001). Post-simulation, 60% of patients improved their insight, i.e., reduced SADS (from 8 to 6.5, P = 0.0001) compared to 25% of controls (P = 0.02). The mean percentage SADS reduction was also higher in cirrhotics (18% vs. 8%, P = 0.03). MHE on ICT patients had a significantly higher SADS improvement (P = 0.004) compared to the other patients; no difference was seen in those with/without MHE due to the PHES. The percentage SADS reduction in patients was correlated with getting lost (r = 0.468, P < 0.0001), crashes (P = 0.002), and centerline/road-edge excursions (P = 0.01). There was a significantly higher percentage SADS reduction in cirrhotics who got lost (25%) compared to those who did not get lost (12%) and controls (8%, P = 0.014).

CONCLUSIONS

Insight into driving skills in cirrhosis improves after driving simulation and is highest in those with navigation errors and MHE on ICT. Driving simulator-associated insight improvement may be the first step towards the cognitive rehabilitation of driving skills in cirrhosis.

Hepatic encephalopathy and health-related quality of life

The impact of overt hepatic encephalopathy on health-related quality of life is well defined, but it remains to be demonstrated how much the presence of minimal hepatic encephalopathy (MHE) might impair patients' perceived health status. MHE reduces cognitive abilities, with specific impairment in manual abilities, which can lead to a depressed mood that impairs perceived health status. Therefore, all subjects with cirrhosis should be systematically screened for MHE by validated tools. Early detection and treatment is mandatory to improve the quality of life of patients with advanced cirrhosis, their social isolation, and their daily lives.

Rifaximin in the treatment of hepatic encephalopathy

Hepatic encephalopathy is a challenging complication in patients with advanced liver disease. It can be defined as a neuropsychiatric syndrome caused by portosystemic venous shunting, ranging from minimal to overt hepatic encephalopathy or coma. Its pathophysiology is still unclear, although increased levels of ammonia play a key role. Diagnosis of hepatic encephalopathy is currently based on specific tests evaluating the neuropsychiatric state of patients and their quality of life; the severity of hepatic encephalopathy is measured by the West Haven criteria. Treatment of hepatic encephalopathy consists of pharmacological and corrective measures, as well as nutritional interventions. Rifaximin received approval for the treatment of hepatic encephalopathy in 2010 because of its few side effects and pharmacological benefits. The aim of this work is to review the use and efficacy of rifaximin both in acute and long-term management of hepatic encephalopathy. Treatment of overt hepatic encephalopathy involves management of the acute episode as well as maintenance of remission in those patients who have previously experienced an episode, in order to improve their quality of life. The positive effect of rifaximin in reducing health care costs is also discussed.

Previous overt hepatic encephalopathy rather than minimal hepatic encephalopathy impairs health-related quality of life in cirrhotic patients

BACKGROUND

It has been observed that overt hepatic encephalopathy (HE) is accompanied by a persistent cognitive defect, suggesting that HE may not be fully reversible. The health-related quality-of-life (HRQoL) has been shown to be impaired by cirrhosis, and, according to some reports, influenced by minimal HE. Little is known about the effect of previous HE on HRQoL.

AIM

To investigate the relative impact of previous HE and minimal HE on HRQoL in a group of consecutively hospitalized cirrhotic patients.

PATIENTS/METHODS

Seventy five consecutive cirrhotic patients were evaluated using the Psychometric HE Score (PHES) and simplified Psychometric HE Score (SPHES) to detect the presence of minimal HE and using SF-36 to assess the HRQoL, both corrected for age and education. Eighteen of them had previous bouts of overt HE.

RESULTS

Minimal HE was significantly more frequent in patients with previous HE than in those without (p < 0.001), independently on the method used for the diagnosis (PHES or SPHES). A deeper impairment in several domains of SF-36 was observed in patients with previous bouts of overt HE, in those with ascites, as well as in those with decompensated cirrhosis. At multivariate analysis, ascites, MELD score and previous HE were independently related to the mental-component-summary (MCS) of SF-36, whereas ascites was the only variable independently associated with the physical-component-summary (PCS) of SF-36. Minimal HE (independently on the method used for its diagnosis) impaired only one domain of SF-36.

CONCLUSIONS

These data suggest that previous bouts of HE, despite their complete clinical resolution, play an independent role in producing a persistent impairment in HRQoL of cirrhotics.

PROMIS computerised adaptive tests are dynamic instruments to measure health-related quality of life in patients with cirrhosis

BACKGROUND

Cirrhotic patients have an impaired health-related quality of life (HRQOL), which is usually analysed using static paper-pencil questionnaires. The Patient Reported Outcomes Measurement Information System (PROMIS) computerised adaptive testing (CAT) are flexible, freely available, noncopyrighted, HRQOL instruments with US-based norms across 11 domains. CAT presents five to seven questions/domain depending on the patient's response, from large validated question banks. This provides brevity and precision equivalent to the entire question bank.

AIM

To evaluate PROMIS CAT tools against 'legacy instruments' for cirrhotics and their informal caregivers.

METHODS

A total of 200 subjects: 100 cirrhotics (70 men, 53% decompensated) and 100 caregivers were administered the PROMIS and legacy instruments [Sickness Impact Profile (SIP), Beck depression/anxiety inventories, Pittsburgh Sleep-Quality Index (PSQI) and Epworth Sleepiness scale (ESS)] concurrently. Both legacy and PROMIS results for patients were compared with caregivers and US norms. These were also compared between compensated and decompensated patients. Preference for SIP or PROMIS was inquired of a selected group (n = 70, 50% patients). Test - retest reliability was assessed in another group of 20 patients.

RESULTS

Patients had significant impairment on all PROMIS domains apart from anger and anxiety compared with caregivers and US norms (P < 0.02 to <0.0001). Decompensated patients had significantly worse sleep, pain, social and physical function scores compared with compensated ones, similar to legacy instruments. There was a statistically significant correlation between PROMIS and their corresponding legacy instruments. The majority (71%) preferred PROMIS over SIP. PROMIS tools had significant test - retest reliability (ICC range 0.759-0.985) when administered 12 ± 6 days apart.

CONCLUSION

PROMIS computerised adaptive testing tools had significant concurrent and discriminant validity, test - retest reliability and subject preference for assessing HRQOL in cirrhotic patients.

Randomised clinical trial: rifaximin improves health-related quality of life in cirrhotic patients with hepatic encephalopathy - a double-blind placebo-controlled study

BACKGROUND

Hepatic encephalopathy (HE) is a brain disorder that often results from cirrhosis due to viral hepatitis, metabolic and alcohol-related liver disease, and is characterised by cognitive, psychiatric and motor impairments. Recurrent bouts of overt HE negatively impact daily functioning and quality of life.

AIM

To evaluate the effect of rifaximin on health-related quality of life (HRQL) in cirrhotic patients with HE.

METHODS

Patients with cirrhosis in remission from HE (Conn score = 0 or 1) and a documented history of recurrent HE episodes (≥2 within 6 months of screening) were randomised to rifaximin 550 mg twice daily (N = 101) or placebo (N = 118) for 6 months. Concomitant lactulose was permitted during the study. The Chronic Liver Disease Questionnaire (CLDQ) was administered every 4 weeks, and time for occurrence of HE breakthrough was recorded. A longitudinal analysis using time-weighted averages of the CLDQ scores normalised by days on study therapy was used to evaluate the effect of treatment on HRQL, and between HE outcomes (HE recurrence, yes/no) irrespective of treatment.

RESULTS

The time-weighted averages of the overall CLDQ score and each domain score were significantly higher in the rifaximin group vs. placebo (P-values ranged from 0.0087 to 0.0436); and were significantly lower in patients who experienced HE breakthrough compared to those who remained in remission (P-values were <0.0001).

CONCLUSION

Rifaximin significantly improved HRQL in patients with cirrhosis and recurrent hepatic encephalopathy. A lower HRQL may predict recurrence of hepatic encephalopathy.

Pathogenesis, diagnosis, and treatment of hepatic encephalopathy

Hepatic encephalopathy (HE) is a neuropsychiatric disorder seen in patients with advanced liver disease or porto-systemic shunts. Based on etiology and severity of HE, the World Congress of Gastroenterology has divided HE into categories and sub-categories. Many user-friendly computer-based neuropsychiatric tests are being validated for diagnosing covert HE. Currently, emphasis is being given to view HE deficits as a continuous spectrum rather than distinct stages. Ammonia is believed to play crucial role in pathogenesis of HE via astrocyte swelling and cerebral edema. However, evidence has been building up which supports the synergistic role of oxidative stress, inflammation and neurosteroids in pathogenesis of HE. At present, treatment of HE aims at decreasing the production and intestinal absorption of ammonia. But as the role of new pathogenetic mechanisms becomes clear, many potential new treatment strategies may become available for clinician.