Lactulose improves psychometric testing in cirrhotic patients with subclinical encephalopathy

Efficacy and Safety of Variable Treatment Options in the Prevention of Hepatic Encephalopathy: A Systematic Review and Network Meta-Analysis

There are no guidelines for the most effective medication to reduce hepatic encephalopathy (HE) or the associated mortality. The purpose of this study is to determine the most effective possible treatment among the single treatment options or the combined treatment options for decreasing the morbidity and mortality of HE. We evaluated the outcomes by various parameters such as the quality of life, reduction in ammonia, all causes of mortality, adverse events, reversal of minimal HE, and development of overt HE. We systematically searched PubMed, Cochrane, Web of Science, and Scopus till the 19th of January 2023 for studies that assess various treatment options for HE. Data were extracted from eligible studies and pooled in a frequentist network meta-analysis as standardized mean difference (SMD) and their 95% confidence interval (CI) using the MetaInsight web-based tool. The Cochrane Tool was used to assess the randomized controlled trials' quality (RCT), while the NIH tool was used to assess the quality of the included cohort studies. Utilizing the R software, the network meta-analysis was conducted. In addition to a significant variation in cases of (Lactulose and Rifaximin) compared with Rifaximin (RR= 0.39, 95% CI [0.17; 0.89]), the results demonstrated a significantly lower incidence of overt HE in (Lactulose and Rifaximin) compared with placebo (RR=0.19, 95% CI [0.09; 0.40]). Most arms demonstrated a statistically significant reduction in the incidence of overt HE compared to albumin and placebo. The results also demonstrated a significant reduction in ammonia between L-ornithine-L-aspartate (LOLA) and probiotics (MD= -19.17, 95% CI [-38.01; -0.32]), as well as a significant difference in the incidence of LOLA compared to placebo (MD= -22.62, 95% CI [-39.16; -6.07]). This network meta-analysis has significant data for managing subclinical HE in people without a history of overt HE. Our analysis showed that (Lactulose and Rifaximin), followed by (Rifaximin and L-carnitine), followed by (Lactulose and Rifaximin with zinc) were the best combinations regarding overt HE. LOLA reduced ammonia best, followed by Nitazoxanide and finally Lactulose. (Lactulose and Nitazoxanide) have the least adverse effects, followed by (Rifaximin and L-carnitine), then Probiotics. Yet, all mortality outcomes and quality of life changes yielded no useful findings. Future studies like RCTs must be done to compare our therapies directly.

Nutritional therapy for persistent cognitive impairment after resolution of overt hepatic encephalopathy in patients with cirrhosis: A double-blind randomized controlled trial

BACKGROUND AND AIM

Minimal hepatic encephalopathy (MHE) reflects cognitive impairment in patients with liver cirrhosis and is associated with poor prognosis. We assessed the effects of nutritional therapy on cognitive functions, health-related quality of life (HRQOL), anthropometry, endotoxins, and inflammatory markers in cirrhotic patients with MHE.

METHODS

In a double-blind randomized controlled trial, cirrhotic patients with MHE were randomized to nutritional therapy (group I: 30-35 kcal/kg/day and 1.0-1.5 g of protein/kg/day) and no nutritional therapy (group II: diet as patients were taking before) for 6 months. MHE was diagnosed based on psychometric hepatic encephalopathy score (PHES). Anthropometry, ammonia, endotoxins, inflammatory markers, myostatin, and HRQOL were assessed at baseline and after 6 months. Primary endpoints were improvement or worsening in MHE and HRQOL.

RESULTS

A total of 150 patients were randomized to group I (n = 75, age 46.3 ± 12.5 years, 58 men) and group II (n = 75, age 45.2 ± 9.3 years, 56 men). Baseline PHES (-8.16 ± 1.42 vs -8.24 ± 1.43; P = 0.54) was comparable in both groups. Reversal of MHE was higher in group I (73.2% vs 21.4%; P = 0.001) than group II. Improvement in PHES (Δ PHES 4.0 ± 0.60 vs -4.18 ± 0.40; P = 0.001), HRQOL (Δ Sickness Impact Profile 3.24 ± 3.63 vs 0.54 ± 3.58; P = 0.001), anthropometry, ammonia, endotoxins, cytokines, and myostatin levels was also significantly higher in group I than group II. Overt hepatic encephalopathy developed in 6 patients in group I and 13 in group II (P = 0.04).

CONCLUSIONS

Nutritional therapy is effective in treatment of MHE and associated with improvement in nutritional status, HRQOL, ammonia, endotoxins, inflammatory markers, and myostatin levels.

Minimal Hepatic Encephalopathy Affects Daily Life of Cirrhotic Patients: A Viewpoint on Clinical Consequences and Therapeutic Opportunities

Minimal hepatic encephalopathy (MHE) is a frequent complication of hepatic encephalopathy (HE) and can affect up to 80% of patients with liver cirrhosis. It is characterized by the lack of obvious clinical signs and the presence of alterations detectable using psychometric or electrophysiological testing focused on attention, working memory, psychomotor speed and visuospatial ability. Ideally, each patient should be tested for this condition because, despite the absence of symptoms, it has severe repercussions on daily life activities. It may be responsible for an inability to drive, sleep disturbances, risk of falls and inability to work. Some studies have highlighted its prognostically unfavorable role on mortality and risk of "overt" HE (OHE). Finally, MHE severely affects the lives of patients and caregivers, altering their quality of life and their socioeconomic status. Several treatments have been proposed for MHE treatment, including non-absorbable disaccharides, poorly absorbable antibiotics, such as rifaximin, probiotics and branched-chain amino acids, with promising results. For this reason, early diagnosis and intervention with appropriate measures is essential, with the aim of improving both performance on psychometric tests, as well as clinical aspects related to this condition.

Heretical thoughts into hepatic encephalopathy

Clinical progress in the development of new diagnostic modalities and therapeutic strategies for the management of patients with hepatic encephalopathy has lagged behind the vast knowledge that has been generated from basic studies. In this article, we critically assess matters that should be revisited, such as definition, classification, diagnosis and grading of hepatic encephalopathy, which are difficult to apply reproducibly using the current criteria. Many lines of investigation have confirmed that hepatic encephalopathy is irreversible in many patients and suggest the need for further studies focussing on mechanisms of neuronal injury and death, to guide future drug development for these patients. The clinical evidence behind using lactulose for all severities of hepatic encephalopathy, which is currently considered the standard of care, is poor and placebo-controlled trials for hepatic encephalopathy should be considered ethically sound. This expert opinion identifies current challenges in hepatic encephalopathy and highlights areas which require further debate and investigation in order to help advance the field both scientifically and clinically.

Current approach to treatment of minimal hepatic encephalopathy in patients with liver cirrhosis

Minimal hepatic encephalopathy (MHE) corresponds to the earliest stage of hepatic encephalopathy (HE). MHE does not present clinically detectable neurological-psychiatric abnormalities but is characterized by imperceptible neurocognitive alterations detected during routine clinical examination via neuropsychological or psychometrical tests. MHE may affect daily activities and reduce job performance and quality of life. MHE can increase the risk of accidents and may develop into overt encephalopathy, worsening the prognosis of patients with liver cirrhosis. Despite a lack of consensus on the therapeutic indication, interest in finding novel strategies for prevention or reversion has led to numerous clinical trials; their results are the main objective of this review. Many studies address the treatment of MHE, which is mainly based on the strategies and previous management of overt HE. Current alternatives for the management of MHE include measures to maintain nutritional status while avoiding sarcopenia, and manipulation of intestinal microbiota with non-absorbable disaccharides such as lactulose, antibiotics such as rifaximin, and administration of different probiotics. This review analyzes the results of clinical studies that evaluated the effects of different treatments for MHE.

Hepatic Encephalopathy: Diagnosis and Management

Type C hepatic encephalopathy (HE) is a brain dysfunction caused by severe hepatocellular failure or presence of portal-systemic shunts in patients with liver cirrhosis. In its subclinical form, called “minimal hepatic encephalopathy (MHE), only psychometric tests or electrophysiological evaluation can reveal alterations in attention, working memory, psychomotor speed and visuospatial ability, while clinical neurological signs are lacking. The term “covert” (CHE) has been recently used to unify MHE and Grade I HE in order to refer to a condition that is not unapparent but also non overt. “Overt” HE (OHE) is characterized by personality changes, progressive disorientation in time and space, acute confusional state, stupor and coma. Based on its time course, OHE can be divided in Episodic, Recurrent or Persistent. Episodic HE is generally triggered by one or more precipitant factors that should be found and treated. Unlike MHE, clinical examination and clinical decision are crucial for OHE diagnosis and West Haven criteria are widely used to assess the severity of neurological dysfunction. Primary prophylaxis of OHE is indicated only in the patient with gastrointestinal bleeding using non-absorbable antibiotics (Rifaximin) or non-absorbable disaccharides (Lactulose). Treatment of OHE is based on the identification and correction of precipitating factors and starting empirical ammonia-lowering treatment with Rifaximin and Lactulose (per os and enemas). The latter should be used for secondary prophylaxis, adding Rifaximin if HE becomes recurrent. In recurrent/persistent HE, the treatment options include fecal transplantation, TIPS revision and closure of eventual splenorenal shunts. Treatment of MHE should be individualized on a case-by-case basis.

Important Unresolved Questions in the Management of Hepatic Encephalopathy: An ISHEN Consensus

Management of hepatic encephalopathy (HE) remains challenging from a medical and psychosocial perspective. Members of the International Society for Hepatic Encephalopathy and Nitrogen Metabolism recognized 5 key unresolved questions in HE management focused on (i) driving, (ii) ammonia levels in clinical practice, (iii) testing strategies for covert or minimal HE, (iv) therapeutic options, and (v) nutrition and patient-reported outcomes. The consensus document addresses these topical issues with a succinct review of the literature and statements that critically evaluate the current science and practice, laying the groundwork for future investigations.

Low-Value Levels: Ammonia Testing Does Not Improve the Outcomes of Overt Hepatic Encephalopathy

Hepatic encephalopathy is a clinical diagnosis. However, many clinicians measure ammonia levels in hospitalized patients presenting with hepatic encephalopathy. In this editorial, we review the results of an important study by Haj and Rockey. The authors examined the management decisions effected affected by and outcomes associated with (i) ordering an ammonia level and (ii) knowing the ammonia level. They found that ammonia level determination did not impact affect clinical decision-making or patient outcomes. These persuasive data demonstrate the limited clinical utility of ammonia levels and highlight the need for testing stewardship to dissuade unnecessary use through educational efforts and decision supports.

Comparative Efficacy of Treatment Options for Minimal Hepatic Encephalopathy: A Systematic Review and Network Meta-Analysis

BACKGROUND & AIMS

We aimed to synthesize evidence for most effective treatments for minimal hepatic encephalopathy (HE) and prevention of overt HE in patients with cirrhosis.

METHODS

We performed a systematic search of the PubMed, EMBASE, OvidSP, and Cochrane Central Register of Controlled Trials databases through July 26, 2018, for randomized controlled trials evaluating treatments for minimal HE in patients with cirrhosis, with primary outcomes of reversal of minimal HE or prevention of overt HE. We conducted a meta-analysis and then used network meta-analysis and surface under cumulated ranking (SUCRA) to pool the direct and indirect estimates and rank the different treatments. We appraised study quality using the Grading of Recommendations Assessment, Development and Evaluation system.

RESULTS

Our meta-analysis and network meta-analysis included 25 trials, comprising 1563 participants. Agents found to be effective in reversing minimal HE compared with placebo or no treatment included rifaximin (odds ratio [OR], 7.53; 95% predictive interval [PrI], 4.45-12.73; SUCRA, 89.2%; moderate quality), lactulose (OR, 5.39; 95% PrI, 3.60-8.0; SUCRA, 67.2%; moderate quality), the combination of probiotics and lactulose (OR, 4.66; 95% PrI, 1.90-11.39; SUCRA, 52.4%; low quality), L-ornithine L-aspartate (OR, 4.45; 95% PrI, 2.67-7.42; SUCRA, 47.2%; low moderate quality), and probiotics (OR, 3.89; 95% PrI, 2.52-6.02; SUCRA, 34.1%; low quality). Agents found to be effective in preventing episodes of overt HE compared with placebo or no treatment included L-ornithine L-aspartate (OR, 0.19; 95% PrI, 0.04-0.91; SUCRA, 75.1%; high moderate quality), lactulose (OR, 0.22; 95% PrI, 0.09-0.52; SUCRA, 73.9%; moderate quality), and probiotics (OR, 0.27; 95% PrI, 0.11-0.62; SUCRA, 59.6%; low quality).

CONCLUSIONS

In a meta-analysis of data from 25 trials, we found rifaximin and lactulose to be most effective for reversal of minimal HE in patients with cirrhosis. L-ornithine L-aspartate and lactulose are most effective in the prevention of overt HE. Lactulose was the only agent that was effective in reversing minimal HE, preventing overt HE, reducing ammonia, and improving quality of life, with tolerable adverse effects. International prospective register of systematic reviews ID: 107003.

The Efficacy of Lactulose for the Treatment of Hyperammonemic Encephalopathy Due to Severe Heart Failure

Hyperammonemic encephalopathy secondary to heart failure is rare and there had been little reports about effective treatment. Organ hypoperfusion or congestion by heart failure may lead to various organ dysfunctions, and liver and intestinal circulatory impairment might cause ammonia metabolic failure. Here, we report on the case of a patient with hyperammonemic encephalopathy that was secondary to heart failure, which was effectively treated by lactulose.

Pathophysiology of hepatic encephalopathy and future treatment options

Understanding of the pathophysiology of hepatic encephalopathy has conditioned new treatment options. Ammonia detoxification in hepatic encephalopathy is regulated by two enzymes: glutaminase or glutamine synthetase. The first produces ammonia and the second detoxifies the ammonia, which is why treatments are aimed at glutaminase inhibition or glutamine synthetase activation. At present, we know that both enzymes are found not only in the liver, but also in the muscle, intestine, kidney, and brain. Therefore, current treatments can be directed at each enzyme at different sites. Awareness of those potential treatment sites makes different options of approach possible in the patient with hepatic encephalopathy, and each approach should be personalized.

Hepatic encephalopathy 2018: A clinical practice guideline by the Italian Association for the Study of the Liver (AISF)

Hepatic encephalopathy (HE) is a common, worrisome and sometimes difficult to manage complication of end-stage liver disease. HE is often recurrent, requiring multiple hospital admissions. It can have serious implications in terms of a patient's ability to perform complex tasks (for example driving), their earning capacity, their social and family roles. This guideline reviews current knowledge on HE definition, pathophysiology, diagnosis and treatment, both by general principles and by way of a summary of available drugs and treatment strategies. The quality of the published, pertinent evidence is graded, and practical recommendations are made. Where possible, these are placed within the Italian health service context, with reference to local diagnosis and management experience.

How to Design a Multicenter Clinical Trial in Hepatic Encephalopathy

The design of clinical trials on Hepatic Encephalopathy (HE) is not an easy task, in fact there are several issues related to the performance of clinical trials in HE that have impeded progress in the field, mainly because most of the studies on HE therapy were performed before the era of rigorous Randomized Controlled Trials (RCTs). In this review we discuss the major problems affecting previously published trials on HE treatments aiming to provide evidences, suggestions and indications to prepare well designed RCTs in three different settings: (1) management of hospitalized patients with episodic HE; (2) secondary prophylaxis in patients following an episode of HE; and (3) management of minimal/covert HE.

The burden of minimal hepatic encephalopathy: from diagnosis to therapeutic strategies

Minimal hepatic encephalopathy (MHE) is the mildest form of hepatic encephalopathy (HE). It affects the performance of psychometric tests focused on attention, working memory, psychomotor speed, and visuospatial ability, as well as electrophysiological and other functional brain measures. MHE is a frequent complication of liver disease, affecting up to 80% of tested patients. By being related to falls, an impairment in fitness to drive and the development of overt HE, MHE severely affects the lives of patients and caregivers by altering their quality of life and their socioeconomic status. MHE is detected in clinically asymptomatic patients using appropriate psychometric tests and neurophysiological methods that highlight neuropsychological alterations, such as video-spatial orientation deficits, attention disorders, memory, reaction times, electroencephalogram slowing, prolongation of latency-evoked cognitive potentials, and reduction in the critical flicker frequency. Several treatments have been proposed for MHE treatment, including non-absorbable disaccharides, poorly absorbable antibiotics such as rifaximin, probiotics and branched-chain amino acids. However, because of the multiple diagnosis methods, the various endpoints of treatment trials and the variety of agents used in trials, the treatment of MHE is not currently recommended as routine, but only on a case-by-case basis.

Sleep disturbances in patients of liver cirrhosis with minimal hepatic encephalopathy before and after lactulose therapy

Sleep disturbances are common in patients of cirrhosis with minimal hepatic encephalopathy (MHE) and affect health related quality of life (HRQOL). No study has evaluated effect of lactulose on sleep disturbances and correlation with HRQOL in patients with MHE. We assessed sleep disturbances in cirrhosis with MHE and effect of lactulose on sleep disturbances and HRQOL. One hundred patients of cirrhosis [MHE; (n = 50, age 45.3 ± 11.2 years, 45 males) no-MHE (n = 50, age 46.3 ± 10.4 years, 44 males)] were included. MHE was diagnosed with psychometric hepatic encephalopathy score (PHES) ≤ -5. All patients underwent laboratory parameters including arterial ammonia and critical flicker frequency (CFF) Sleep disturbances were measured with Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS) and polysomnography. HRQOL was measured with SF-36(v2) questionnaire. Patients with MHE were given lactulose therapy for 3 months and all the parameters were repeated. Poor quality of sleep and excessive day time sleepiness were more common in patients with MHE, compared to without MHE. With lactulose therapy there was improvement in MHE in 21 patients and arterial ammonia levels (93.74 ± 14.8 vs. 71.44 ± 18.8 μmol/L: p < 0.001), CFF (34.83 ± 3.54 vs. 39.44 ± 4.95 Hz: p < 0.001), PHES (-7.64 ± 2.1 vs. -5.58 ± 2.09: p < 0.001), PSQI (8.6 ± 3.3 vs. 5.2 ± 1.5: p < 0.001), ESS (12.52 ± 3.01 vs. 9.24 ± 2.27: p < 0.001) and HRQOL (p = 0.01). Excessive day time sleepiness and impaired sleep quality are common in patients with MHE and correlate with neuropsychiatric impairment. Improvement in MHE with lactulose also leads to improvement in sleep disturbances and HRQOL.

Minimal hepatic encephalopathy in cirrhosis- how long to treat?

INTRODUCTION

Minimal hepatic encephalopathy (MHE) can reverse after short-term treatment. However, relapse rate of MHE after stopping treatment has not been studied so far. We aimed to evaluate long-term (9 months) efficacy of a short-term (3 months) treatment of MHE with lactulose/rifaximin, for maintenance of remission from MHE.

MATERIAL AND METHODS

In this prospective study, consecutive patients with cirrhosis and MHE were treated with lactulose/rifaximin for 3 months. After treatment, they were followed up for 6 months. Psychometric testing for diagnosis of MHE was performed at baseline, 3 months and 9 months.

RESULTS

Of the 527 patients screened, 351 were found eligible and tested for MHE. Out of these, 112 (31.9%) patients had MHE (mean age 55.3 years; 75% males). They were randomized to receive Rifaximin (n = 57; 1,200 mg/day) or Lactulose (n = 55; 30-120 mL/day) for three months. At 3 months, 73.7% (42/57) patients in Rifaximin group experienced MHE reversal compared to 69.1% (38/55) in Lactulose group (p = 0.677). Six months after stopping treatment, 47.6% (20/42) in rifaximin group and 42.1% (16/38) patients in lactulose group experienced MHE relapse (p = 0.274). The overt hepatic encephalopathy development rate (7.1% vs. 7.9%) and mortality rate (0.23% vs. 0%) were similar in both groups. The Child-Turcotte-Pugh score and model for end stage liver disease (MELD) scores of patients who had MHE relapse were higher compared to those who didn't. On multivariate regression analysis, MELD score was an independent predictor of MHE relapse.

CONCLUSION

Of the patients who became MHE negative after short-term (3 months) treatment with rifaximin/lactulose, almost 50% had a relapse of MHE at 6 months follow-up.

Recent developments in the diagnosis and treatment of covert/minimal hepatic encephalopathy

The terms minimal hepatic encephalopathy and covert hepatic encephalopathy are defined. Clinical assessment is unreliable and both require the use of diagnostic tools. Of these, psychometric tests are the most widely used. They require proper standardization and may be biased by patient cooperation or lack thereof. The measure of the critical flicker frequency and of the electroencephalogram, possibly quantified, are also useful. The alteration of any of them is not strictly parallel in size and may vary from patient to patient. When possible, the use of multiple measures might increase diagnostic reliability. These functional measures should be interpreted within the clinical/biochemical profile of the patient to exclude other disorders. A flow chart for treatment is proposed on the basis of current knowledge.

Nonabsorbable disaccharides for hepatic encephalopathy: A systematic review and meta-analysis

Nonabsorbable disaccharides (NADs) have been used to treat hepatic encephalopathy (HE) since 1966. However, a Cochrane Review, published in 2004, found insufficient evidence to recommend their use in this context. This updated systematic review evaluates the effects of the NADs, lactulose and lactitol, for the treatment and prevention of HE in patients with cirrhosis. Thirty-eight randomized controlled trials, involving 1,828 patients, were identified through electronic and manual searches; 31 randomized controlled trials looked at the treatment of HE, while seven looked at its primary/secondary prevention. Random-effects meta-analyses showed that, compared to placebo/no intervention, NADs had a beneficial effect on HE (relative risk [RR] = 0.63, 95% confidence interval [CI] 0.53-0.74, number needed to treat [NNT] = 4) and serious liver-related adverse events such as liver failure, variceal bleeding, serious infections, spontaneous bacterial peritonitis, and hepatorenal syndrome (RR = 0.42, 95% CI 0.26-0.69, NNT = 50). Treatment was also associated with a reduction in mortality in patients with overt HE (RR = 0.36, 95% CI 0.14-0.94, NNT = 20), although not in patients with minimal HE. Meta-analyses of the prevention randomized controlled trials showed that NADs prevented the development of HE (RR = 0.47, 95% CI 0.33-0.68, NNT = 6), the risk of developing serious liver-related adverse events (RR = 0.48, 95% CI 0.33-0.70, NNT = 6), and reduced mortality (RR = 0.63, 95% CI 0.40-0.98, NNT = 20). Use of NADs was associated with nonserious gastrointestinal adverse events. There were no differences in the efficacy or safety of lactulose and lactitol.

CONCLUSIONS

NADs have beneficial effects in the treatment and prevention of HE; their use, in this context, confers additional benefits including a reduction in serious liver-related morbidities and all-cause mortality. (Hepatology 2016;64:908-922).

Spectral electroencephalogram in liver cirrhosis with minimal hepatic encephalopathy before and after lactulose therapy

BACKGROUND AND AIM

Minimal hepatic encephalopathy (MHE) represents the mildest form of hepatic encephalopathy. Spectral electroencephalogram (sEEG) analysis improves the recognition of MHE by decreasing inter-operator variability and providing quantitative parameters of brain dysfunction. We compared sEEG in patients with cirrhosis with and without MHE and the effects of lactulose on sEEG in patients with MHE.

METHODS

One hundred patients with cirrhosis (50 with and 50 without MHE) were enrolled. Diagnosis of MHE was based on psychometric hepatic encephalopathy score (PHES) of ≤ -5. Critical flicker frequency, model of end-stage liver disease score, and sEEG were performed at baseline in all patients. The spectral variables considered were the mean dominant frequency (MDF) and relative power in beta, alpha, theta, and delta bands. Patients with MHE were given 3 months of lactulose, and all parameters were repeated.

RESULTS

Spectral electroencephalogram analysis showed lower MDF (7.8 ± 1.7 vs 8.7 ± 1.3 Hz, P < 0.05) and higher theta relative power (34.29 ± 4.8 vs 24 ± 6.7%, P = 001) while lower alpha relative power (28.6 ± 4.0 vs 33.5 ± 5.3%, P = .001) in patients with MHE than in patients without MHE. With theta relative power, sensitivity 96%, specificity 84%, and accuracy of 90% were obtained for diagnosis of MHE. After lactulose treatment, MHE improved in 21 patients, and significant changes were seen in MDF (7.8 ± 0.5 vs 8.5 ± 0.6), theta (34.2 ± 4.8 vs 23.3 ± 4.1%), alpha (28.6 ± 4.0 vs 35.5 ± 4.5%), and delta relative power (13.7 ± 3.5 vs 17.0 ± 3.3%) after treatment (P ≤ 0.05).

CONCLUSIONS

Spectral EEG is a useful objective and quantitative tool for diagnosis and to assess the response to treatment in patients with cirrhosis with MHE.

Non-absorbable disaccharides versus placebo/no intervention and lactulose versus lactitol for the prevention and treatment of hepatic encephalopathy in people with cirrhosis

BACKGROUND

Non-absorbable disaccharides (lactulose and lactitol) are recommended as first-line treatment for hepatic encephalopathy. The previous (second) version of this review included 10 randomised clinical trials (RCTs) evaluating non-absorbable disaccharides versus placebo/no intervention and eight RCTs evaluating lactulose versus lactitol for people with cirrhosis and hepatic encephalopathy. The review found no evidence to either support or refute the use of the non-absorbable disaccharides and no differences between lactulose versus lactitol.

OBJECTIVES

To assess the beneficial and harmful effects of i) non-absorbable disaccharides versus placebo/no intervention and ii) lactulose versus lactitol in people with cirrhosis and hepatic encephalopathy.

SEARCH METHODS

We carried out electronic searches of the Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL 2015, Issue 10), MEDLINE, EMBASE, and Science Citation Index Expanded to 19 October 2015; manual searches of meetings and conference proceedings; checks of bibliographies; and correspondence with investigators and pharmaceutical companies.

SELECTION CRITERIA

We included RCTs, irrespective of publication status, language, or blinding.

DATA COLLECTION AND ANALYSIS

Two review authors, working independently, retrieved data from published reports and correspondence with investigators. The primary outcomes were mortality, hepatic encephalopathy, and serious adverse events. We presented the results of meta-analyses as risk ratios (RR) and mean differences (MD) with 95% confidence intervals (CI). We assessed the quality of the evidence using 'Grading of Recommendations Assessment Development and Evaluation' (GRADE) and bias control using the Cochrane Hepato-Biliary Group domains. Our analyses included regression analyses of publication bias and other small study effects, Trial Sequential Analyses to detect type 1 and type 2 errors, and subgroup and sensitivity analyses.

MAIN RESULTS

We included 38 RCTs with a total of 1828 participants. Eight RCTs had a low risk of bias in the assessment of mortality. All trials had a high risk of bias in the assessment of the remaining outcomes. Random-effects meta-analysis showed a beneficial effect of non-absorbable disaccharides versus placebo/no intervention on mortality when including all RCTs with extractable data (RR 0.59, 95% CI 0.40 to 0.87; 1487 participants; 24 RCTs; I(2) = 0%; moderate quality evidence) and in the eight RCTs with a low risk of bias (RR 0.63, 95% CI 0.41 to 0.97; 705 participants). The Trial Sequential Analysis with the relative risk reduction (RRR) reduced to 30% confirmed the findings when including all RCTs, but not when including only RCTs with a low risk of bias or when we reduced the RRR to 22%. Compared with placebo/no intervention, the non-absorbable disaccharides were associated with beneficial effects on hepatic encephalopathy (RR 0.58, 95% CI 0.50 to 0.69; 1415 participants; 22 RCTs; I(2) = 32%; moderate quality evidence). Additional analyses showed that non-absorbable disaccharides can help to reduce serious adverse events associated with the underlying liver disease including liver failure, hepatorenal syndrome, and variceal bleeding (RR 0.47, 95% CI 0.36 to 0.60; 1487 participants; 24 RCTs; I(2) = 0%; moderate quality evidence). We confirmed the results in Trial Sequential Analysis. Tests for subgroup differences showed no statistical differences between RCTs evaluating prevention, overt, or minimal hepatic encephalopathy. The evaluation of secondary outcomes showed a potential beneficial effect of the non-absorbable disaccharides on quality of life, but we were not able to include the data in an overall meta-analysis (very low quality evidence). Non-absorbable disaccharides were associated with non-serious (mainly gastrointestinal) adverse events (very low quality evidence). None of the RCTs comparing lactulose versus lactitol evaluated quality of life. The review found no differences between lactulose and lactitol for the remaining outcomes (very low quality evidence).

AUTHORS' CONCLUSIONS

This review includes a large number of RCTs evaluating the prevention or treatment of hepatic encephalopathy. The analyses found evidence that non-absorbable disaccharides may be associated with a beneficial effect on clinically relevant outcomes compared with placebo/no intervention.

Non-absorbable disaccharides versus placebo/no intervention and lactulose versus lactitol for the prevention and treatment of hepatic encephalopathy in people with cirrhosis

BACKGROUND

Non-absorbable disaccharides (lactulose and lactitol) are recommended as first-line treatment for hepatic encephalopathy. The previous (second) version of this review included 10 randomised clinical trials (RCTs) evaluating non-absorbable disaccharides versus placebo/no intervention and eight RCTs evaluating lactulose versus lactitol for people with cirrhosis and hepatic encephalopathy. The review found no evidence to either support or refute the use of the non-absorbable disaccharides and no differences between lactulose versus lactitol.

OBJECTIVES

To assess the beneficial and harmful effects of i) non-absorbable disaccharides versus placebo/no intervention and ii) lactulose versus lactitol in people with cirrhosis and hepatic encephalopathy.

SEARCH METHODS

We carried out electronic searches of the Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL 2015, Issue 10), MEDLINE, EMBASE, and Science Citation Index Expanded to 19 October 2015; manual searches of meetings and conference proceedings; checks of bibliographies; and correspondence with investigators and pharmaceutical companies.

SELECTION CRITERIA

We included RCTs, irrespective of publication status, language, or blinding.

DATA COLLECTION AND ANALYSIS

Two review authors, working independently, retrieved data from published reports and correspondence with investigators. The primary outcomes were mortality, hepatic encephalopathy, and serious adverse events. We presented the results of meta-analyses as risk ratios (RR) and mean differences (MD) with 95% confidence intervals (CI). We assessed the quality of the evidence using 'Grading of Recommendations Assessment Development and Evaluation' (GRADE) and bias control using the Cochrane Hepato-Biliary Group domains. Our analyses included regression analyses of publication bias and other small study effects, Trial Sequential Analyses to detect type 1 and type 2 errors, and subgroup and sensitivity analyses.

MAIN RESULTS

We included 38 RCTs with a total of 1828 participants. Eight RCTs had a low risk of bias in the assessment of mortality. All trials had a high risk of bias in the assessment of the remaining outcomes. Random-effects meta-analysis showed a beneficial effect of non-absorbable disaccharides versus placebo/no intervention on mortality when including all RCTs with extractable data (RR 0.59, 95% CI 0.40 to 0.87; 1487 participants; 24 RCTs; I(2) = 0%; moderate quality evidence) and in the eight RCTs with a low risk of bias (RR 0.63, 95% CI 0.41 to 0.97; 705 participants). The Trial Sequential Analysis with the relative risk reduction (RRR) reduced to 30% confirmed the findings when including all RCTs, but not when including only RCTs with a low risk of bias or when we reduced the RRR to 22%. Compared with placebo/no intervention, the non-absorbable disaccharides were associated with beneficial effects on hepatic encephalopathy (RR 0.58, 95% CI 0.50 to 0.69; 1415 participants; 22 RCTs; I(2) = 32%; moderate quality evidence). Additional analyses showed that non-absorbable disaccharides can help to reduce serious adverse events associated with the underlying liver disease including liver failure, hepatorenal syndrome, and variceal bleeding (RR 0.47, 95% CI 0.36 to 0.60; 1487 participants; 24 RCTs; I(2) = 0%; moderate quality evidence). We confirmed the results in Trial Sequential Analysis. Tests for subgroup differences showed no statistical differences between RCTs evaluating prevention, overt, or minimal hepatic encephalopathy. The evaluation of secondary outcomes showed a potential beneficial effect of the non-absorbable disaccharides on quality of life, but we were not able to include the data in an overall meta-analysis (very low quality evidence). Non-absorbable disaccharides were associated with non-serious (mainly gastrointestinal) adverse events (very low quality evidence). None of the RCTs comparing lactulose versus lactitol evaluated quality of life. The review found no differences between lactulose and lactitol for the remaining outcomes (very low quality evidence).

AUTHORS' CONCLUSIONS

This review includes a large number of RCTs evaluating the prevention or treatment of hepatic encephalopathy. The analyses found evidence that non-absorbable disaccharides may be associated with a beneficial effect on clinically relevant outcomes compared with placebo/no intervention.

Efficacy of Nutritional Therapy for Patients With Cirrhosis and Minimal Hepatic Encephalopathy in a Randomized Trial

BACKGROUND & AIMS

Minimal hepatic encephalopathy (MHE) impairs health-related quality of life (HRQOL), leads to the development of overt HE, and is associated with poor outcome. We performed a randomized controlled trial to assess the effects of nutritional therapy on cognitive functions and HRQOL in patients with cirrhosis with MHE.

METHODS

In a tertiary care setting in New Delhi, India, patients with cirrhosis with MHE were assigned randomly to groups given nutritional therapy (30-35 kcal/kg/d, 1.0-1.5 g vegetable protein/kg/d; n = 60; age, 42.1 ± 10.3 y; 48 men) or no nutritional therapy (patients continued on their same diet; n = 60; age, 42.4 ± 9.6 y; 47 men) for 6 months in 2014. MHE was diagnosed based on their psychometry hepatic encephalopathy score (PHES). HRQOL was assessed by a sickness impact profile (SIP) questionnaire. Primary end points were improvement or worsening in MHE and improvement in HRQOL.

RESULTS

There was no significant difference in baseline PHES (-8.12 ± 1.32 vs -8.53 ± 1.38; P = .08) or SIP (14.25 ± 5.8 vs 15.44 ± 5.03; P = .85) scores. After the 6-month study period, a higher proportion of patients in the nutritional therapy group had reversal of MHE (71.1% vs 22.8%; P = .001). Patients in the nutritional therapy group also had larger increases in PHES (3.86 ± 3.58 vs 0.52 ± 4.09; P = .001) and HRQOL (improvement in SIP score of 3.24 ± 3.63 vs 0.54 ± 3.58; P = .001). Overt HE developed in 10% of patients in the nutritional therapy group vs 21.7% of the control group (P = .04).

CONCLUSIONS

Based on a randomized controlled trial performed in India, nutritional therapy is effective in the treatment of MHE and is associated with improvement in HRQOL. Clinical Trial Registry-India registration no: CTRI/2013/07/003851.

Covert and Overt Hepatic Encephalopathy: Diagnosis and Management

Hepatic encephalopathy (HE) is part of a spectrum of neurocognitive changes in cirrhosis. HE is divided into 2 broad categories based on severity: covert hepatic encephalopathy (CHE) and overt hepatic encephalopathy (OHE). CHE has a significant impact on a patient's quality of life, driving performance, and recently has been associated with increased hospitalizations and death. Likewise, OHE is associated with increased rates of hospitalizations and mortality, and poor quality of life. Given its significant burden on patients, care takers, and the health care system, early diagnosis and management are imperative. In addition, focus also should be directed on patient and family member education on the disease progression and adherence to medications. Treatment strategies include the use of nonabsorbable disaccharides, antibiotics (ie, rifaximin), and, potentially, probiotics. Other therapies currently under further investigation include L-ornithine-L-aspartate, ornithine phenylacetate, glycerol phenylbutyrate, molecular adsorbent recirculating system, and albumin infusion.

Clinical and pathophysiological consequences of alterations in the microbiome in cirrhosis

Cirrhosis is a major cause of mortality worldwide. Exponential rises in prevalence have been observed secondary to increases in obesity and alcohol consumption. Multiple lines of evidence implicate gut-derived bacteria and bacterial ligands as a central driver of pathogenesis. Recent developments in culture-independent techniques have facilitated a more accurate description of microbiome composition in cirrhosis and led to the description of measures of dysbiosis shown to be associated with disease. More importantly, metagenomic studies are adding to an understanding of the functional contribution of the microbiota and may prove to be a more clinically relevant biomarker than phylogenetic studies. Much like other dysbiotic states such as inflammatory bowel disease, the microbiota in cirrhosis is characterized by a low microbial and genetic diversity. Therapeutic strategies to diminish this process are currently limited to selective intestinal decontamination with antibiotics. This review summarizes the available data and develops a framework for the use of current and future treatment strategies to diminish the consequences of dysbiosis in cirrhosis. Interventional strategies to bind bacterial products in the gut lumen and blood, and modulate the magnitude of host sensing mechanisms remain an unmet clinical need. A greater understanding of the host-microbiota interaction in cirrhosis is of key importance to inform future interventional strategies to diminish the currently escalating burden of the disease.

Covert Hepatic Encephalopathy: Who Should Be Tested and Treated?

Covert hepatic encephalopathy is a common problem in cirrhosis, affecting up to 80% of patients. It is defined as test-dependent brain dysfunction with clinical consequences in the setting of cirrhosis in patients who are not disoriented. Because it is not apparent clinically, and diagnostic testing has not been standardized, the issue has often been ignored in clinical practice. Yet, the clinical consequences are notable, including impaired quality of life, diminished work productivity, and poor driving skills.

Management of covert hepatic encephalopathy

Hepatic encephalopathy is a reversible progressive neuropsychiatric disorder that encompasses a wide clinical spectrum. Covert hepatic encephalopathy is defined as patients with minimal hepatic encephalopathy and Grade I encephalopathy by West-Haven Criteria. Terminology such as "sub-clinical", "latent", and "minimal" appear to trivialize the disease and have been replaced by the term covert. The lack of clinical signs means that covert hepatic encephalopathy is rarely recognized or treated outside of clinical trials with options for therapy based on patients with episodic hepatic encephalopathy. This review discusses the current available options for therapy in covert hepatic encephalopathy and focuses on non-absorbable disacharides (lactulose or lactitol), antibiotics (rifaximin), probiotics/synbiotics and l-ornithine-l-aspartate.

Treatment options for covert hepatic encephalopathy

OPINION STATEMENT

The main issue with treating covert hepatic encephalopathy (HE) is to establish whether it is cost effective to reverse the neuropsychiatric abnormalities that define this mild form of HE. Until fairly recently, covert HE was rarely diagnosed, but advances in computerized psychometric testing have greatly simplified its detection. The many consequences of covert HE are now being identified, and most have been shown to be reversible with standard HE treatment. Perhaps the most enticing possibility will be the potential that standard HE therapies will postpone the onset of overt HE. This will require further evaluation with large placebo-controlled randomized trials.

Disaccharides in the treatment of hepatic encephalopathy

Management of hepatic encephalopathy (HE) primarily involves avoidance of precipitating factors and administration of various ammonia-lowering therapies such as nonabsorbable disaccharides and antimicrobial agents like rifaximin. The nonabsorbable disaccharides which include lactulose and lactitol are considered the first-line therapy for the treatment of HE and minimal hepatic encephalopathy (MHE). Lactulose significantly improves cognitive function and health-related quality of life in patients with MHE. Lactitol is comparable to lactulose in the treatment of HE with fewer side effects. Lactulose has also shown to be effective in primary and secondary prophylaxis of HE. Disaccharides were found to be comparable to rifaximin in recent systemic reviews in the treatment of HE however conclusion was based on inclusion of some poor quality trials. Combination therapy of disaccharides either with rifaximin, L-ornithine L-aspartate,probiotics for the treatment of HE needs further validation in large studies.

Gut microbiota and hepatic encephalopathy

There is a strong relationship between liver and gut; while the portal venous system receives blood from the gut, and its contents may affect liver functions, liver in turn, affects intestinal functions through bile secretion. There is robust evidence that the pathogenesis of hepatic encephalopathy (HE) is linked to alterations in gut microbiota and their by-products such as ammonia, indoles, oxindoles, endotoxins, etc. In the setting of intestinal barrier and immune dysfunction, these by-products are involved in the pathogenesis of complications of liver cirrhosis including HE and systemic inflammation plays an important role. Prebiotics, probiotics and synbiotics may exhibit efficacy in the treatment of HE by modulating the gut flora. They improve derangement in flora by decreasing the counts of pathogenic bacteria and thus improving the endotoxemia, HE and the liver disease. Current evidence suggest that the trials evaluating the role of probiotics in the treatment of HE are of not high quality and all trials had high risk of bias and high risk of random errors. Therefore, the use of probiotics for patients with HE cannot be currently recommended. Further RCTs are required. This review summarizes the main literature findings about the relationships between gut flora and HE, both in terms of the pathogenesis and the treatment of HE.

Motor vehicle accidents: How should cirrhotic patients be managed?

Motor vehicle accidents (MVAs) are serious social issues worldwide and driver illness is an important cause of MVAs. Minimal hepatic encephalopathy (MHE) is a complex cognitive dysfunction with attention deficit, which frequently occurs in cirrhotic patients independent of severity of liver disease. Although MHE is known as a risk factor for MVAs, the impact of diagnosis and treatment of MHE on MVA-related societal costs is largely unknown. Recently, Bajaj et al demonstrated valuable findings that the diagnosis of MHE by rapid screening using the inhibitory control test (ICT), and subsequent treatment with lactulose could substantially reduce the societal costs by preventing MVAs. Besides the ICT and lactulose, there are various diagnostic tools and therapeutic strategies for MHE. In this commentary, we discussed a current issue of diagnostic tools for MHE, including neuropsychological tests. We also discussed the advantages of the other therapeutic strategies for MHE, such as intake of a regular breakfast and coffee, and supplementation with zinc and branched chain amino acids, on the MVA-related societal costs.

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.

Treatment options for hepatic encephalopathy

Few formal treatment guidelines exist for managing hepatic encephalopathy. The nonabsorbable disaccharide, lactulose, is considered the first-line therapeutic agent for treating hepatic encephalopathy. Acidification of the gastrointestinal tract is the principal mechanism by which the drug inhibits production of ammonia by coliform bacteria. Elevated ammonia levels are seen in more than 80% of patients with hepatic encephalopathy. Systemic antibiotics, primarily neomycin, have also been employed to reduce bacterial production of ammonia, but associated adverse events limit their use in patients with hepatic encephalopathy. The semisynthetic, nonsystemic antibiotic, rifaximin, was approved in March 2010 by the United States Food and Drug Administration for the treatment of overt hepatic encephalopathy. Rifaximin decreases intestinal production and absorption of ammonia by altering gastrointestinal flora and is almost completely excreted unchanged in the feces. Rifaximin has been effective in improving behavioral, laboratory, mental, and intellectual abnormalities in patients with hepatic encephalopathy. The drug was compared with lactulose in well-designed clinical studies in patients with hepatic encephalopathy. Rifaximin was generally found to be equal or superior to lactulose in these studies. Although dosages have varied, most medical centers use a dosage of rifaximin 400 mg 3 times/day for hepatic encephalopathy. Recent clinical trials have used 550 mg twice/day in order to improve patient compliance. Additional clinical trials are being undertaken to further define the efficacy and safety of rifaximin in hepatic encephalopathy.

Clinical efficacy and safety of lactulose for minimal hepatic encephalopathy: a meta-analysis

OBJECTIVE

To evaluate the clinical efficacy of lactulose in patients with minimal hepatic encephalopathy (MHE).

METHODS

Randomized controlled trials (RCTs) comparing lactulose with placebo or with no intervention in the management of MHE that were conducted from January 1990 to July 2011 were searched from MEDLINE, EMBASE, SCI, Cochrane Controlled Trials Register, and China Biological Medicine Database. Studies with a Jadad score higher than 3 were included in the meta-analysis and evaluated using RevMan5.0 software for relative risk (RR) or weighted mean difference (WMD) with 95% confidence intervals (95% CI). Sensitivity analysis was performed on the ethnical differences and quality of the trials. Publication bias was observed using an inverted funnel plot.

RESULTS

Nine studies with 434 patients were included in the meta-analysis. Compared with placebo or no intervention, lactulose significantly reduced the risk of no improvement in neuropsychological tests (RR: 0.52, 95% CI: 0.44-0.62, P<0.00001), the time required for the completion of the number connection test-A (WMD: -26.95, 95% CI: -37.81 to -16.10, P<0.00001), and the mean number of abnormal neuropsychological tests (WMD: -1.76, 95% CI: -1.96 to -1.56, P<0.00001). Furthermore, the meta-analysis also showed that lactulose prevented the progression to overt hepatic encephalopathy (RR: 0.17, 95% CI: 0.06-0.52, P=0.002), reduced blood ammonia levels (WMD: -9.89 µmol/l, 95% CI: -11.01 to -8.77 µmol/l, P<0.00001), and improve health-related quality of life (WMD: -6.05, 95% CI: -6.30 to -5.20, P<0.00001). However, no significant difference was observed in the mortality of patients with MHE (RR: 0.75, 95% CI: 0.21-2.72, P=0.66), and lactulose significantly increased the incidence of diarrhea (RR: 4.38, 95% CI: 1.35-14.25, P=0.01).

CONCLUSION

Lactulose has significant beneficial effects for patients with MHE compared with placebo or no intervention.

A randomized controlled trial comparing lactulose, probiotics, and L-ornithine L-aspartate in treatment of minimal hepatic encephalopathy

BACKGROUND

Minimal hepatic encephalopathy (MHE) impairs daily functioning and health-related quality of life (HRQoL). The modalities of treatment of MHE have not been adequately studied.

AIMS

To compare lactulose, probiotics, and L-ornithine L-aspartate (LOLA) in treatment of MHE and effect on HRQoL by Sickness Impact Profile questionnaire.

METHODS

Consecutive patients with cirrhosis were screened for MHE. MHE was diagnosed by two or more abnormal psychometric tests (number/figure connection tests A and B, block design test, picture completion test). Patients were randomized to no treatment (GpA), lactulose 30-60 ml/twice per day (GpB), probiotics 110 billion colony forming units twice in a day (GpC), LOLA 6 g three times per day (GpD) for 3 months. Arterial ammonia and HRQoL assessment using SIP questionnaire was done at baseline and at 3 months.

RESULTS

One hundred and sixty (49.69%) of 322 patients with cirrhosis had MHE. After 3 months, MHE recovered in GpA four (10%), GpB 19 (47.5%), GpC 14 (35%), and GpD 14 (35%). MHE improved significantly in all three treatment groups (GpB, GpC, GpD) compared with no treatment (GpA) (P=0.006). Overt hepatic encephalopathy developed in nine (5.6%) of 160 patients; GpA four (10%), GpB one (2.5%), GpC two (5%), and GpD two (5%), respectively. There was significant improvement in SIP score in GpB (6.98±4.1), GpC (6.24±3.4), and GpD (7.33±3.8) versus GpA (1.05±2.6), P value of less than 0.001. The decrease in SIP score correlated with an improvement in MHE on multivariate analysis but there was no correlation with the type of intervention offered. There was no significant change in arterial ammonia level after therapy in GpA (-0.52±7.8 μmol/l). Arterial ammonia level in GpB (-8.47±5.8 μmol/l), GpC (-7.31±7.9 μmol/l), and GpD (-9.61±9.3 μmol/l) were significantly more than GpA (P<0.0001).

CONCLUSION

Lactulose, probiotics, and LOLA significantly improve MHE and HRQoL in patients with chronic liver disease.

Meta-analysis: the effects of gut flora modulation using prebiotics, probiotics and synbiotics on minimal hepatic encephalopathy

BACKGROUND

Minimal hepatic encephalopathy (MHE) is characterised by subtle neurocognitive deficits without overt clinical manifestations. Although several trials have individually evaluated the role of prebiotics, probiotics and synbiotics, there is yet no consensus on the management of MHE.

AIM

To estimate the efficacy of prebiotics, probiotics and synbiotics in MHE in randomised controlled trials.

METHODS

MEDLINE, EMBASE, CINAHL and the Cochrane Database of Systematic Reviews were searched for published studies in all languages. Inclusion and exclusion criteria were defined a priori. Pooled relative risk and heterogeneity were estimated as the measures of association.

RESULTS

Nine studies met our inclusion criteria. Use of prebiotics, probiotics and synbiotics significantly reduced the pooled relative risk (RR) of no improvement of MHE (RR 0.40, 95% CI 0.32-0.50; P<0.001). Upon subgroup analysis, five studies with lactulose showed significant reduction of risk of no improvement of MHE (RR 0.34, 95% CI 0.24-0.47; P<0.0001) with no inter-trial heterogeneity. In two trials each of probiotics and synbiotics, their use was associated with significant beneficial effects (RR 0.41, 95% CI 0.26-0.65; P<0.0001 and RR of 0.51, 95% CI 0.32-0.80; P=0.004 respectively). There were no major adverse events though probiotics and synbiotics were better tolerated than lactulose.

CONCLUSIONS

The use of prebiotics, probiotics and synbiotics was associated with significant improvement in minimal hepatic encephalopathy. Among individual agents, lactulose appears to have the most beneficial effect, followed closely by probiotics and synbiotics.

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

OBJECTIVES

Cirrhotics with minimal hepatic encephalopathy (MHE) have a poor health-related quality of life (HRQOL). Treatment of MHE is still evolving. The aim of this double-blind randomized pilot study was to assess the efficacy of rifaximin in improving neuropsychometric (NP) test performance and HRQOL in patients with MHE.

METHODS

MHE was diagnosed if any two NP tests (number and figure connection tests, picture completion, digit symbol, and block design tests) were deranged beyond 2 s.d. of normal. HRQOL was assessed using the sickness impact profile (SIP) questionnaire.

RESULTS

A total of 486 patients with cirrhosis were screened and 284 were found eligible. Out of these 115 (40.9%) had MHE, of which 21 refused consent and 94 were randomized to receive placebo (n=45) and rifaximin (n=49; 1200 mg/day) for 8 weeks. At the end of treatment, significantly more number of patients in rifaximin group showed reversal of MHE (75.5% (37/49) vs. 20% (9/45) in placebo group; P<0.0001). Rifaximin group also showed significant reduction in mean number of abnormal NP tests (baseline, 2.35 (95% confidence interval (CI), 2.17-2.53); 2 weeks, 1.29 (95% CI, 1.02-1.56), P=0.002; 8 weeks, 0.81 (95% CI, 0.61-1.02), P=0.000), compared with placebo group (baseline, 2.31 (95% CI, 2.03-2.59); 2 weeks, 2.03 (95% CI, 1.74-2.31); 8 weeks, 1.97 (95% CI, 1.69-2.25), P>0.05). The mean total SIP score also improved significantly in rifaximin group (baseline, 11.67 (95% CI, 10.31-13.03); 8 weeks, 6.45 (95% CI, 5.59-7.30); P=0.000) compared with placebo group (baseline, 9.86 (95% CI, 8.66-11.06); 8 weeks, 8.51 (95% CI, 7.35-9.67); P=0.82). Improvement in HRQOL correlated with improvement in NP tests. Rifaximin was well tolerated.

CONCLUSIONS

Rifaximin significantly improves both cognitive functions and HRQOL in patients with MHE.

Rifaximin for the treatment of hepatic encephalopathy

Hepatic encephalopathy (HE) is a complication of cirrhosis, the severity of which can range from subtle, neurocognitive dysfunction (minimal HE) to more apparent and severe cognitive and motor manifestations with increasing grades of the condition (overt HE). Current treatment options are targeted at reducing the levels of ammonia and other gut-derived toxins, the purported culprits behind the pathogenesis of HE. One of these therapeutic options, the nonsystemic antibiotic rifaximin, is efficacious for the treatment of minimal and overt HE. However, HE may be a cyclic condition in which patients with overt HE enter remission following treatment and then relapse. Thus, safe, effective and well-tolerated treatments are needed to maintain HE remission. Rifaximin maintained HE remission more effectively than placebo in a large, randomized controlled trial. Rifaximin is safe and well-tolerated for the treatment of minimal and overt HE and for the maintenance of HE remission.

Minimal hepatic encephalopathy: consensus statement of a working party of the Indian National Association for Study of the Liver

Hepatic encephalopathy (HE) is a major complication that develops in some form and at some stage in a majority of patients with liver cirrhosis. Overt HE occurs in approximately 30-45% of cirrhotic patients. Minimal HE (MHE), the mildest form of HE, is characterized by subtle motor and cognitive deficits and impairs health-related quality of life. The Indian National Association for Study of the Liver (INASL) set up a Working Party on MHE in 2008 with a mandate to develop consensus guidelines on various aspects of MHE relevant to clinical practice. Questions related to the definition of MHE, its prevalence, diagnosis, clinical characteristics, pathogenesis, natural history and treatment were addressed by the members of the Working Party.

Predictors of nonresponse to lactulose for minimal hepatic encephalopathy in patients with cirrhosis

BACKGROUND/AIMS

Minimal hepatic encephalopathy (MHE) impairs health-related quality of life and predicts overt hepatic encephalopathy (HE) in cirrhotic patients. Lactulose is effective in the treatment of MHE. However, not all patients respond to lactulose. We evaluated predictors of nonresponse to lactulose.

PATIENTS AND METHODS

Consecutive 110 cirrhotic patients without HE were evaluated for MHE by psychometry, P300 auditory event-related potential (P300ERP), venous ammonia and critical flicker frequency (CFF). MHE was diagnosed by abnormal psychometry and P300ERP (>2 SD). MHE patients were treated with lactulose for 1 month. Response was defined by normalization of the abnormal test parameters (both psychometric tests and P300ERP).

RESULTS

Sixty patients (54.5%) were diagnosed as having MHE: 17/39 (44%) in Child's A, 21/42 (50%) Child's B and 22/29 (76%) in Child's C. There was a significant difference between Child's C's vs Child's A's and B's (P<0.05). Abnormal psychometric tests and abnormal P300ERP were seen in 74 (67%) and 74 (67%) patients respectively. Of 60 patients with MHE, after treatment, psychometry remained abnormal in 22 (36.6%) and P300ERP in 21 (35%) patients. CFF was<38 Hz in 34 (57%) and 11 (18%) patients, respectively, before and after treatment in MHE patients. There was a significant difference between the baseline serum sodium level (134.7+/-2.6 vs 131.1+/-2.2 mmol/L, P=0.001) and the venous ammonia level (76.6+/-20.7 vs 113.4+/-22.8 micromol/L, P=0.001) between responders vs nonresponders. Receiver operating characteristic analysis was performed to identify the cutoff for venous ammonia [cutoff 93.5 mmol/L, area under the curve (AUC) 0.892 (0.814-0.970)] and for the serum sodium level [cutoff 132.5 mmol/L, AUC 0.874 (0.779-0.998)]. Taking a cutoff of 93.5 mmol/L for ammonia patient had a sensitivity of 88.5% and a specificity of 79.4%, respectively, and a cutoff of 132.5 mmol/L for serum sodium patient had a sensitivity of 76.5% and a specificity of 88.5% for nonresponse to lactulose. On univariate analysis and multivariate analysis, serum sodium and venous ammonia were the only two parameters associated with nonresponse to lactulose.

CONCLUSION

The prevalence of MHE was 55% and MHE improved in 57% patients with lactulose. Baseline low serum sodium and high venous ammonia were highly predictive of nonresponse to lactulose therapy.

Minimal hepatic encephalopathy

Minimal hepatic encephalopathy (MHE) is the mildest form of spectrum of hepatic encephalopathy (HE). Patients with MHE have no recognizable clinical symptoms of HE but have mild cognitive and psychomotor deficits. The prevalence of MHE is high in patients with cirrhosis of liver and varies between 30% and 84%; it is higher in patients with poor liver function. The diagnostic criteria for MHE have not been standardized but rest on careful patient history and physical examination, normal mental status examination, demonstration of abnormalities in cognition and/or neurophysiological function, and exclusion of concomitant neurological disorders. MHE is associated with impaired health-related quality of life, predicts the development of overt HE and is associated with poor survival. Hence, screening all patients with cirrhosis for MHE using psychometric tests, and treatment of those patients diagnosed to have MHE has been recommended. Ammonia plays a key role in the pathogenesis of MHE, which is thought to be similar to that of overt HE. Thus, ammonia-lowering agents such as lactulose and probiotics have been tried. These agents have been shown to improve cognitive and psychometric deficits, and have good safety profile. Future studies will better define the role of other drugs, such as rifaximin, acetyl L-carnitine and L-ornithine L-aspartate.

Treatment of minimal hepatic encephalopathy

Several reports, conducted as a placebo-controlled, double-blind study, presented a favorable result in treating MHE. They included branched chain aminoacid, fluzazenil-a benzodiazepin receptor antagonist, lactulose, lactitol, and L-ornithin-L-aspartate. Lactulose and lactitol have been shown to be effective in MHE. It improved psychomotor tests and lowered ammonia levels as well as quality of life. Branched chain amino acids (BCAAs) were reported to improve nitrogen metabolism, blood ammonia level, and psychomotor tests. Flumazenil, an antagonist of benzodiazepine receptor, has not been associated with established consensus on the effectiveness in MHE. L-ornithine-L-aspartate (OA) exerts its ammonia-lowering action in the kidney, skeletal muscles, brain, as well as in the liver. OA administered per orally improved number connection test, ammonia levels, and mental state. OA may be a promising therapy for patients with MHE. A shunt-closure manipulation with balloon occluded retrograde transvenous obliteration (BRTO) has been shown to be effective for hepatic encephalopathy and its efficacy in MHE has not been elucidated. Synbiotic modulation of gut flora. was shown to increase fecal content of non-urease-producing Lactobacillus species and this change was associated with a reversal of MHE. In conclusion, there are no definitive conclusion on the treatment of MHE because of difficulties in diagnosis and evaluation. Therapeutic strategy should be planned specifically for each patient depending on the etiological factors.

The cost-effectiveness and budget impact of competing therapies in hepatic encephalopathy - a decision analysis

BACKGROUND

Treatment options for hepatic encephalopathy have disparate risks and benefits. Non-absorbable disaccharides and neomycin are limited by uncertain efficacy and common dose-limiting side effects. In contrast, rifaximin is safe and effective in hepatic encephalopathy, but is more expensive.

METHODS

We conducted a decision analysis to calculate the cost-effectiveness of six strategies in hepatic encephalopathy: (i) no hepatic encephalopathy treatment, (ii) lactulose monotherapy, (iii) lactitol monotherapy, (iv) neomycin monotherapy, (v) rifaximin monotherapy and (vi) up-front lactulose with crossover to rifaximin if poor response or intolerance of lactulose ('rifaximin salvage'). The primary outcome was cost per quality-adjusted life-year gained.

RESULTS

Under base-case conditions, 'do nothing' was least effective and rifaximin salvage was most effective. Lactulose monotherapy was least expensive, and rifaximin monotherapy was most expensive. When balancing cost and effectiveness, lactulose monotherapy and rifaximin salvage dominated alternative strategies. Compared to lactulose monotherapy, rifaximin salvage cost an incremental US$2315 per quality-adjusted life-year-gained. The cost of rifaximin had to fall below US$1.03/tab in order for rifaximin monotherapy to dominate lactulose monotherapy.

CONCLUSIONS

Rifaximin monotherapy is not cost-effective in the treatment of chronic hepatic encephalopathy at current average wholesale prices. However, a hybrid salvage strategy, reserving rifaximin for lactulose-refractory patients, may be highly cost-effective.

Critical flicker frequency: diagnostic tool for minimal hepatic encephalopathy

BACKGROUND/AIMS

Minimal hepatic encephalopathy (MHE) is associated with poorer quality of life and increased work disability. Diagnosis requires cumbersome psychometric and neurophysiological tests. We evaluated critical flicker frequency (CFF) to diagnose MHE.

METHODS

156 cirrhotic patients (age 41+/-12.5 yr) without overt encephalopathy (Child A 63, Child B 56, Child C 37) were evaluated by psychometric (number connection tests A, B or figure connection tests A, B), P300 auditory event related potential (ERP) and CFF. MHE was diagnosed by abnormal psychometric and/or P300 auditory event related potential.

RESULTS

Prevalence of MHE was 53% with 27 (43%) in Child's A, 33 (59%) in Child's B and 23 (62%) in Child's C cirrhosis (p=NS). Of 83 patients, 72 (87%) had abnormal psychometry, 64 (77%) had abnormal P300 auditory event related potential (ERP) (380.6+/-28.8 ms) and in 66 (80%) CFF was below 39 Hz. 60 (83%) patients with abnormal psychometry and 51 (80%) with abnormal P300 auditory event related potential had CFF below 39 Hz. CFF sensitivity (96%), specificity (77%) and positive predictive value (68%), negative predictive value (98%) and diagnosis accuracy was 83.3% when compared to patients with both abnormal psychometry and P300ERP.

CONCLUSIONS

Critical flicker frequency is a simple, reliable and accurate test without any age or literacy dependence for the diagnosis of MHE.