Evaluation of neuropsychological function in patients with liver cirrhosis with special reference to their driving ability

The burden of hepatic encephalopathy and the use of albumin as a potential treatment

As a potential sequela of cirrhosis, hepatic encephalopathy (HE) significantly impacts the lives of patients and caregivers and places a substantial burden on the healthcare system. With an increasing incidence over time and a cumulative effect on cognition, HE adversely effects quality of life, morbidity and mortality in patients with cirrhosis. HE can range from minimal or covert (MHE/CHE) to overt and symptomatic (OHE). HE has profound impacts on the health and wellbeing of patients and their families and caregivers. Effective treatments could improve the quality of life for all those affected. In this article, we discuss the existing treatments for HE and focus on the potential role of albumin in the treatment of HE. Currently approved therapies for HE (lactulose and rifaximin) are focused on decreasing the formation of ammonia in the gastrointestinal tract. Among the many agents with alternative mechanisms being investigated for treatment of HE, albumin has been studied in clinical trials with acute (≤ 3 days), short-term (up to 2 weeks) prolonged (> 2 weeks) and long-term administration (months). Current studies indicate that acute or short-term administration of albumin does not provide significant benefit for patients with OHE. However, there is increasing evidence that prolonged or long-term albumin therapy can help improve cognition in OHE and prevent recurrence. Additional studies are needed to substantiate these positive findings for longer term administration of albumin in HE and to increase our comprehension of the pharmacologic basis of the effects of albumin.

Social Impact of Hepatic Encephalopathy

Hepatic encephalopathy is a medical condition that stems from liver dysfunction, leading to the accumulation of toxins in the bloodstream. This can result in cognitive impairments, mood changes, and motor dysfunction. Its social impact includes challenges in employment, relationships, and daily functioning for affected individuals. Stigma and misunderstanding around the condition can further exacerbate the difficulties faced by both patients and their caregivers. Efforts to raise awareness, improve medical management, and provide support systems can help mitigate the social impact of hepatic encephalopathy.

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.

The Assessment of Driving Fitness Using an On-Road Evaluation in Patients With Cirrhosis

INTRODUCTION

The association between cirrhosis and driving performance is of particular clinical relevance because of the life-threatening safety issues both for the driver with cirrhosis and the general public. Study aims were to assess (i) driving competency through the use of an in-office computerized battery and on-road driving assessment (DriveABLE) and (ii) the association between minimal hepatic encephalopathy (MHE), in-office paper-pencil tools, and additional measures (e.g., frailty, depression, cognitive testing) with unsafe driving.

METHODS

Patients were prospectively recruited from 2 tertiary care liver clinics. In-office tests and in-office and on-road assessments of driving competence were completed. The χ 2 test and 1-way analysis of variance were used to analyze differences among those with and without MHE. Logistic regression was used to evaluate predictors of an indeterminate/fail result on the in-office computerized driving assessment battery (DriveABLE Cognitive Assessment Tool [DCAT]).

RESULTS

Eighty patients participated with a mean age of 57 years, 70% male, 75% Child-Pugh B/C, and 36% with a history of overt hepatic encephalopathy. Thirty percent met MHE criteria on both the psychometric hepatic encephalopathy score and the Stroop app tests. Only 2 patients (3%) were categorized as "unfit to drive" in the on-road driving test, one with MHE and the other without. Fifty-eight percent of the patients were scored as indeterminate/fail on the DCAT. This corresponded to a higher mean number of on-road driving errors (5.3 [SD 2.1] vs 4.2 [SD 1.6] in those who passed the DCAT, P = 0.01). Older age (odds ratio 1.3; confidence interval 1.1, 1.5; P = 0.001) and MHE by Stroop/psychometric hepatic encephalopathy score (odds ratio 11.0; confidence interval 2.3, 51.8; P = 0.002) were independently predictive of worse performance on the DCAT.

DISCUSSION

Worse performance in in-office testing was associated with worse scores on a computerized driving assessment battery and more on-road driving errors, but in-office tools were insufficient to predict on-road driving failures. A diagnosis of MHE should not be used alone to restrict driving in patients with cirrhosis. At-risk patients require on-road driving tests under the supervision of driving regulatory agencies. Future studies should continue to refine and evaluate in-office or at-home testing to predict driving performance.

Hepatic encephalopathy

Hepatic encephalopathy (HE) is a prognostically relevant neuropsychiatric syndrome that occurs in the course of acute or chronic liver disease. Besides ascites and variceal bleeding, it is the most serious complication of decompensated liver cirrhosis. Ammonia and inflammation are major triggers for the appearance of HE, which in patients with liver cirrhosis involves pathophysiologically low-grade cerebral oedema with oxidative/nitrosative stress, inflammation and disturbances of oscillatory networks in the brain. Severity classification and diagnostic approaches regarding mild forms of HE are still a matter of debate. Current medical treatment predominantly involves lactulose and rifaximin following rigorous treatment of so-called known HE precipitating factors. New treatments based on an improved pathophysiological understanding are emerging.

Standardization of the psychometric hepatic encephalopathy score in a French population

The Psychometric Hepatic Encephalopathy Score (PHES) has previously been standardized in thirteen countries on three continents, confirming its status of gold standard test to detect minimal hepatic encephalopathy (MHE). In the meantime, performance has also been shown to vary with variables such as age, education, and barely sex. The present study aimed at standardizing the PHES in a French population. One hundred and ninety-six French healthy participants completed a French version of the paper-and-pencil PHES, involving five tests and six measures. Importantly, the balance was perfect between all levels of the three controlled factors, which were sex, age (seven decade-levels from 20–29 to 80–89 years), and education (two levels below or above 12 years of education). Raw measures were transformed to fit the normal distribution. ANOVAs on transformed variables showed no effect of sex, but an effect of age on all measures, and of education on five measures. Multiple or simple regressions were completed to build up normograms. Thorough analysis of variability within each test failed to find outliers that may bias the results. Comparison between French and seminal German data showed that they highly fitted though cultural and cognitive style specificities could be observed. This is the first study to standardize the PHES in a French population and to extensively explore the effects of sex, age and education using perfectly balanced samples. Subtle differences between countries of the same continent emphasize the need to build up normative data in each country to get accurate PHES in patients.

Loss of skeletal muscle mass affects the incidence of minimal hepatic encephalopathy: a case control study

BACKGROUND

Sarcopenia is a syndrome characterized by progressive and systemic decreases in skeletal muscle mass and muscle strength. The influence or prognosis of various liver diseases in this condition have been widely investigated, but little is known about whether sarcopenia and/or muscle mass loss are related to minimal hepatic encephalopathy (MHE).

METHODS

To clarify the relationship between MHE and sarcopenia and/or muscle mass loss in patients with liver cirrhosis.

METHODS

Ninety-nine patients with liver cirrhosis were enrolled. MHE was diagnosed by a neuropsychiatric test. Skeletal mass index (SMI) and Psoas muscle index (PMI) were calculated by dividing skeletal muscle area and psoas muscle area at the third lumbar vertebra by the square of height in meters, respectively, to evaluate muscle volume.

RESULTS

This study enrolled 99 patients (61 males, 38 females). MHE was detected in 48 cases (48.5%) and sarcopenia in 6 cases (6.1%). Patients were divided into two groups, with or without MHE. Comparing groups, no significant differences were seen in serum ammonia concentration or rate of sarcopenia. SMI was smaller in patients with MHE (46.4 cm2/m2) than in those without (51.2 cm2/m2, P = 0.027). Similarly, PMI was smaller in patients with MHE (4.24 cm2/m2) than in those without (5.53 cm2/m2, P = 0.003). Skeletal muscle volume, which is represented by SMI or PMI was a predictive factor related to MHE (SMI ≥ 50 cm2/m2; odds ratio 0.300, P = 0.002, PMI ≥ 4.3 cm2/m2; odds ratio 0.192, P = 0.001).

CONCLUSIONS

Muscle mass loss was related to minimal hepatic encephalopathy, although sarcopenia was not. Measurement of muscle mass loss might be useful to predict MHE.

Social Impact of Hepatic Encephalopathy

Hepatic encephalopathy (HE) is a multifaceted disorder, with effects stretching far beyond office visits and hospitalizations. Patients with HE suffer from varying degrees of altered consciousness, intellectual disability, and personality changes. A large social impact exists for patients with HE. Quality of life and activities of daily living, such as work capacity, driving ability, and sleep quality, have been shown to be affected. Additionally, caregiver and financial burdens are highly prevalent. Multiple tools exist to assess quality of life, including the CLD-Q questionnaire. Common treatments for HE, including rifaximin and lactulose, have been shown to improve overall quality of life.

The psychomotor vigilance task: Role in the diagnosis of hepatic encephalopathy and relationship with driving ability

BACKGROUND & AIMS

Hepatic encephalopathy (HE) is a syndrome of decreased vigilance and has been associated with impaired driving ability. The aim of this study was to evaluate the psychomotor vigilance task (PVT), which is used to assess both vigilance and driving ability, in a group of patients with cirrhosis and varying degrees of HE.

METHODS

A total of 145 patients (120 males, 59 ± 10 years, model for end-stage liver disease [MELD] score 13 ± 5) underwent the PVT; a subgroup of 117 completed a driving questionnaire and a subgroup of 106 underwent the psychometric hepatic encephalopathy score (PHES) and an electroencephalogram (EEG), based on which, plus a clinical evaluation, they were classed as being unimpaired (n = 51), or as having minimal (n = 35), or mild overt HE (n = 20). All patients were followed up for an average of 13 ± 5 months in relation to the occurrence of accidents and/or traffic offences, HE-related hospitalisations and death. Sixty-six healthy volunteers evenly distributed by sex, age and education served as a reference cohort for the PVT.

RESULTS

Patients showed worse PVT performance compared with healthy volunteers, and PVT indices significantly correlated with MELD, ammonia levels, PHES and the EEG results. Significant associations were observed between neuropsychiatric performance/PVT indices and licence/driving status. PVT, PHES and EEG results all predicted HE-related hospitalisations and/or death over the follow-up period; none predicted accidents or traffic offences. However, individuals with the slowest reaction times and most lapses on the PVT were often not driving despite having a licence. When patients who had stopped driving for HE-related reasons (n = 6) were modelled as having an accident or fine over the subsequent 6 and 12 months, PVT was a predictor of accidents and traffic offences, even after correction for MELD and age.

CONCLUSIONS

The PVT is worthy of further study for the purposes of both HE and driving ability assessment.

LAY SUMMARY

Hepatic encephalopathy (HE) is a complication of advanced liver disease that can manifest as excessive sleepiness. Some patients with HE have been shown to have difficulty driving. Herein, we used a test called the Psychomotor Vigilance Task (PVT), which measures sleepiness and can also be used to assess driving competence. We showed that PVT performance is fairly stable in healthy individuals. We also showed that PVT performance parallels performance in tests which are commonly used in cirrhotic patients to measure HE. We suggest that this test is helpful in quantifying HE and identifying dangerous drivers among patients with cirrhosis.

Alcohol and the Law

In the intersection of alcohol ingestion with the law, medical ethics, and public safety, physicians are often unsure about how to proceed. Physicians' primary focus should be on patient education with an ethical and legal duty to warn the patient of the adverse effects of alcohol. Warning third parties of potential harm related to alcohol-related impairment may involve a breach of patient confidentiality; therefore it should only be undertaken after careful analysis suggests that the risk for significant harm exceeds the burden that results to the patient from warning others. The law remains vague in this area.

Canadian regulations and legal ramifications for hepatic encephalopathy: a descriptive analysis

BACKGROUND

Hepatic encephalopathy, a form of brain dysfunction seen in the setting of liver insufficiency, negatively affects driving performance and so is both a patient and public safety issue. We aimed to review the motor vehicle codes in each Canadian province and territory relating to the reporting of patients with hepatic encephalopathy and to search a Canadian legal database for cases of motor vehicle collisions involving patients with hepatic encephalopathy.

METHODS

In this descriptive analysis, the transportation agencies of each Canadian province and territory were contacted via telephone and/or email between April and August 2017. Requirements of physicians to report medical conditions (including liver disease and hepatic encephalopathy) affecting a patient's fitness to drive were assessed. WestlawNext Canada was searched for any Canadian cases on hepatic encephalopathy and driving-related lawsuits from inception to Dec. 31, 2017.

RESULTS

Reporting of medically unfit drivers is a requirement in all Canadian provinces and territories except Alberta, Quebec and Nova Scotia. Hepatic encephalopathy, cirrhosis and advanced liver disease were not specifically identified as reportable medical conditions in any province or territory. Our search did not identify any lawsuits involving a motor vehicle collision in Canada that were made either against physicians caring for patients with hepatic encephalopathy or against such patients themselves.

INTERPRETATION

Although hepatic encephalopathy has a substantial impact on driving performance, it is not specifically identified as a reportable medical condition in Canada. Increasing awareness of the potential impact of hepatic encephalopathy on safe driving for health care providers and the public is critical.

Covert Hepatic Encephalopathy: Can My Patient Drive?

Liver cirrhosis is a public health problem and hepatic encephalopathy is one of its main complications, which can be either overt meaning thereby evident and readily diagnosed, or covert/minimal (covert hepatic encephalopathy-CHE) needing psychometric testing for diagnosis. Patients with CHE hepatic encephalopathy have deficits in multiple domains including visuospatial assessment, attention, response inhibition, working memory, along with psychomotor speed to name a few areas. These patients have poor navigational skills, get fatigued easily, and demonstrate poor insight into their driving deficits. The combination of all these leads them to have poor driving skills leading to traffic violations and crashes as demonstrated not only on the simulation testing but also in real-life driving events. There are multiple psychometric tests for CHE testing but these are not easily available and there is no uniform consensus on the gold standard testing as of yet. It does not automatically connote that all patients who test positive on driving simulation testing are unfit to drive. The physicians are encouraged to take driving history from the patient and the caregivers on every encounter and focus their counseling efforts more on patients with recent history of traffic crashes, with abnormal simulation studies and history of alcohol cessation within last year. As physicians are not trained to determine fitness to drive, their approach toward CHE patients in regards to driving restrictions should be driven by ethical principles while as respecting the local laws.

Association between road accidents and low-grade hepatic encephalopathy among Sri Lankan drivers with cirrhosis: a prospective case control study

Background

Low-grade hepatic encephalopathy (LGHE) comprises minimal hepatic encephalopathy (MHE) and grade 1 hepatic encephalopathy. LGHE has no or minimal recognizable symptoms but has mild cognitive and psychomotor deficits. Studies in Western countries have demonstrated increased road accidents (RA) among patients with MHE. Our objective was to investigate the association between Sri Lankan LGHE phenotype and RA.

Study design and methods

A prospective, case–control study was conducted in the University Medical Unit, North Colombo Teaching Hospital, Ragama Sri Lanka. Patients with cirrhosis of any aetiology, without OHE, who had been driving during previous 1 month were included. A similar number of age matched, healthy control drivers were also enrolled. Both groups were subjected to five pencil-paper based psychometric tests used to detect LGHE in cirrhotics. Self-reported RA during the previous 1 month were recorded: categorized as ‘major’ when resulted in hospitalization of the involved, ‘minor’ when there were injuries, but not serious enough for hospitalization of the involved and ‘other’ when limited to damages to vehicle or environment without injuries.

Results

Among 55 drivers with cirrhosis and LGHE [males, median age 53 years (range 30–60)], 7 (12.7 %) reported RA compared to 6 (10.9 %) among 55 controls [males; median age 51 years (range 30–60)]. There were no ‘major’ accidents in either group. 2/55 (3.6 %) cases and 2/55 (3.6 %) controls reported ‘minor’ accidents.

Conclusion

There was no increased frequency of RA among Sri Lankan drivers with LGHE compared to healthy controls. This is with the limitation of the study based only on self reported RA.

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.

Minimal hepatic encephalopathy: A review

Minimal hepatic encephalopathy (MHE) is the earliest form of hepatic encephalopathy and can affect up to 80% of patients with liver cirrhosis. By definition, MHE is characterized by cognitive function impairment in the domains of attention, vigilance and integrative function, but obvious clinical manifestation are lacking. MHE has been shown to affect daily functioning, quality of life, driving and overall mortality. The diagnosis can be achieved through neuropsychological testing, recently developed computerized psychometric tests, such as the critical flicker frequency and the inhibitory control tests, as well as neurophysiological procedures. Event related potentials can reveal subtle changes in patients with normal neuropsychological performances. Spectral analysis of electroencephalography (EEG) and quantitative analysis of sleep EEG provide early markers of cerebral dysfunction in cirrhotic patients with MHE. Neuroimaging, in particular MRI, also increasingly reveals diffuse abnormalities in intrinsic brain activity and altered organization of functional connectivity networks. Medical treatment for MHE to date has been focused on reducing serum ammonia levels and includes non-absorbable disaccharides, probiotics or rifaximin. Liver transplantation may not reverse the cognitive deficits associated with MHE. We performed here an updated review on epidemiology, burden and quality of life, neuropsychological testing, neuroimaging, neurophysiology and therapy in subjects with MHE.

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.

Driving Performance Among Patients with Cirrhosis Who Drove to Their Outpatient Hepatology Clinic Appointments

BACKGROUND

Minimal hepatic encephalopathy (MHE) may adversely affect driving skills.

AIMS

To compare the driving performance of cirrhotic patients with and without prior HE as well as controls using a driving stimulator and to correlate psychometric testing with driving performance.

METHODS

Adult patients with cirrhosis, who drove to the outpatient clinic for their routine appointments underwent a battery of driving and psychometric tests including number connection tests A & B (NCT-A and NCT-B), digit symbol test (DST) and critical flicker and fusion frequency (CFF) testing.

RESULTS

Cirrhotics had significantly higher NCT-A (39.3 s vs. 31.2 s, P = 0.006) and DST scores (317 s vs. 245 s, P = 0.012), and lower CFF scores Fusion (33 vs. 36 Hz, P = 0.05), Flicker (35 vs. 42 Hz, P = 0.007) than controls. There was no difference in NCT-A, DST and CFF scores between patients with and without HE. Ten (22%) patients, 7 (27%) with prior HE and 3 (15%) without prior HE, had abnormal NCT-A scores (i.e. >control mean ± 2SD), and 12% of patients with prior HE had one or more driving test accidents, while controls and patients without prior HE had none. Patients with cirrhosis were more likely to hit pedestrians compared to controls (P = 0.05). There was no correlation between CFF, DST and NCTB scores with driving performance test results.

CONCLUSIONS

Unlike previous reports, no significant differences were noted between the patients with and without prior HE on psychometric testing, and on the driving simulator, but driving accidents were seen in only those with previous history of HE.

Diagnosing and treating hepatic encephalopathy

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

The Clinical Relevance of Minimal Hepatic Encephalopathy--A Critical Look

Minimal hepatic encephalopathy (mHE) is diagnosed in patients with severe liver disease but no clinical symptoms of encephalopathy if either neuropsychological or neurophysiological tests indicate cerebral dysfunction and other possible causes of brain dysfunction have been excluded. mHE is characterized by deficits in attention, visuospatial orientation, visuoconstructive abilities and motor function. Accordingly, mHE can be expected to interfere with a subject's working ability, especially in those occupations that require handiwork, and driving ability. Indeed, about 60% of blue-collar workers with mHE have been shown to be assessed as unfit for work compared to only 20% of white-collar workers, and about 50% of patients with mHE have been judged unfit to drive a car in several studies. mHE interferes with a patient's quality of life and is associated with an increased risk of developing overt HE as well as increased mortality. Whether mHE is of importance for cognitive function after liver transplantation has still to be clarified.

Using saccades to diagnose covert hepatic encephalopathy

Covert Hepatic Encephalopathy (CHE), previously known as Minimal Hepatic Encephalopathy, is a subtle cognitive defect found in 30-70 % of cirrhosis patients. It has been linked to poor quality of life, impaired fitness to drive, and increased mortality: treatment is possible. Despite its clinical significance, diagnosis relies on psychometric tests that have proved unsuitable for use in a clinical setting. We investigated whether measurement of saccadic latency distributions might be a viable alternative. We collected data on 35 cirrhosis patients at Addenbrooke's Hospital, Cambridge, with no evidence of clinically overt encephalopathy, and 36 age-matched healthy controls. Performance on standard psychometric tests was evaluated to determine those patients with CHE as defined by the World Congress of Gastroenterology. We then compared visually-evoked saccades between those with CHE and those without, as well as reviewing blood test results and correlating saccadic latencies with biochemical parameters and prognostic scores. Cirrhosis patients have significantly longer median saccadic latencies than healthy controls. Those with CHE had significantly prolonged saccadic latencies when compared with those without CHE. Analysis of a cirrhosis patient's saccades can diagnose CHE with a sensitivity of 75 % and a specificity of 75 %. We concluded that analysis of a cirrhosis patient's saccadic latency distributions is a fast and objective measure that can be used as a diagnostic tool for CHE. This improved early diagnosis could direct avoidance of high-risk activities such as driving, and better inform treatment strategies.

Minimal hepatic encephalopathy impairs quality of life

Minimal hepatic encephalopathy (MHE) is the mildest form of the spectrum of neurocognitive impairment in cirrhosis. It is a frequent occurrence in patients of cirrhosis and is detectable only by specialized neurocognitive testing. MHE is a clinically significant disorder which impairs daily functioning, driving performance, work capability and learning ability. It also predisposes to the development of overt hepatic encephalopathy, increased falls and increased mortality. This results in impaired quality of life for the patient as well as significant social and economic burden for health providers and care givers. Early detection and treatment of MHE with ammonia lowering therapy can reverse MHE and improve quality of life.

Concise review of current concepts on nomenclature and pathophysiology of hepatic encephalopathy

Hepatic encephalopathy is a neuropsychiatric complication of liver cirrhosis the symptoms of which may vary from imperceptible to severe, invaliding, and even lethal. Minimal hepatic encephalopathy is also important because of its tendency to impair patients' cognitive functions and quality of life. The polyetiological pathogenesis of hepatic encephalopathy is intensively studied. A general consensus exists that not only excess of ammonia but also inflammatory, oxidative, and other processes are significant in the development of hepatic encephalopathy.

Minimal hepatic encephalopathy

Minimal hepatic encephalopathy (MHE) is the earliest form of hepatic encephalopathy and can affect up to 80% of cirrhotic patients. By definition, it has no obvious clinical manifestation and is characterized by neurocognitive impairment in attention, vigilance and integrative function. Although often not considered to be clinically relevant and, therefore, not diagnosed or treated, MHE has been shown to affect daily functioning, quality of life, driving and overall mortality. The diagnosis of MHE has traditionally been achieved through neuropsychological examination, psychometric tests or the newer critical flicker frequency test. A new smartphone application (EncephalApp Stroop Test) may serve to function as a screening tool for patients requiring further testing. In addition to physician reporting and driving restrictions, medical treatment for MHE includes non-absorbable disaccharides (eg, lactulose), probiotics or rifaximin. Liver transplantation may not result in reversal of the cognitive deficits associated with MHE.

Serum nitrotyrosine and psychometric tests as indicators of impaired fitness to drive in cirrhotic patients with minimal hepatic encephalopathy

BACKGROUND & AIMS

Cirrhotic patients with minimal hepatic encephalopathy (MHE) show impaired driving ability and increased vehicle accidents. The neurological deficits contributing to impair driving and the underlying mechanisms are poorly understood. Early detection of driving impairment would help to reduce traffic accidents in MHE patients. It would be therefore useful to have psychometric or biochemical parameters reflecting driving impairment. The aims of this work were as follows: (i) to shed light on the neurological deficits contributing to impair driving; (ii) to assess whether some psychometric test or biochemical parameter is a good indicator of driving impairment.

METHODS

We assessed in 22 controls, 36 cirrhotic patients without and 15 with MHE, driving performance using a driving simulator (SIMUVEG) and Driver Test. MHE was diagnosed using the psychometric hepatic encephalopathy score (PHES). Psychometric tests assessing different neurological functions (mental processing speed, attention, visuo-spatial and bimanual coordination) were performed. Blood ammonia and parameters related with nitric oxide-cGMP metabolism, IL-6, IL-18 and 3-nitrotyrosine were measured.

RESULTS

Patients with MHE showed impaired driving ability correlating with MHE grade, with impaired vehicle lateral control in spite of reduced driving speed. Patients with MHE show psychomotor slowing, longer reaction times, impaired bimanual and visuo-spatial coordination and concentrated attention and slowed speed of anticipation and increased blood ammonia, cGMP, IL-6, IL-18 and 3-nitrotyrosine.

CONCLUSIONS

Impaired mental processing speed, attention and alterations in visuo-spatial and motor coordination seem main contributors to impaired driving ability in patients with MHE. Increased serum 3-nitrotyrosine is associated with impaired driving ability.

Prevalence of minimal hepatic encephalopathy and quality of life evaluations in hospitalized cirrhotic patients in China

AIM

To investigate the prevalence of minimal hepatic encephalopathy (MHE) and to assess corresponding health-related quality of life (HRQoL) in hospitalized cirrhotic patients in China.

METHODS

This multi-center cross-sectional study included 16 teaching hospitals, which were members of "Hepatobiliary Cooperation Group, Society of Gastroenterology, Chinese Medical Association", from different areas of China carried out between June and October in 2011. All the eligible hospitalized cirrhotic patients (n = 538) were required to complete triplicate number connection tests combined with one digit symbol test for diagnosing MHE. Patients' clinical examination data were complemented by a modified questionnaire assessing HRQoL. Written informed consent was obtained from each patient.

RESULTS

Male was predominant (68.6%) in 519 patients who met the criteria of the study, with a mean age of 49.17 ± 11.02 years. The most common cause of liver cirrhosis was chronic hepatitis B (55.9%). The prevalence of MHE was 39.9% and varied by Child-Pugh-Classification score (CPC-A: 24.8%, CPC-B: 39.4% and CPC-C: 56.1%, P < 0.01). MHE (P < 0.01) and higher CPC scores (P < 0.01) were associated with a high HRQoL scores (reflecting poorer quality of life). The prevalence of MHE was proportionate to CPC (P = 0.01) and high quality of life scores (P = 0.01).

CONCLUSION

Hospitalized cirrhotic patients have a high prevalence of MHE that is proportionate to the degree of liver function and HRQoL impairment.

Serum endotoxin, inflammatory mediators, and magnetic resonance spectroscopy before and after treatment in patients with minimal hepatic encephalopathy

BACKGROUND

Minimal hepatic encephalopathy (MHE) represents the mildest form of hepatic encephalopathy (HE), with abnormal neuropsychologic findings. Inflammatory response may be important in the pathogenesis of MHE. On magnetic resonance spectroscopy (MRS), improvement of metabolic ratios after liver transplantation suggests an important role of myoinositol (mI) and choline (cho) in the development of MHE.

AIMS

To investigate arterial ammonia, tumor necrosis factor alpha (TNF-α), interleukin (IL)-6, IL-18, serum endotoxin, and MRS before and after treatment in MHE.

PATIENTS AND METHODS

Sixty patients of cirrhosis with MHE were randomized to two groups, Gr. MHE-L (n = 30), treated with lactulose for 3 months, and Gr. MHE-NL (n = 30), who did not received lactulose. Arterial ammonia, TNF-α, IL-6, IL-18, serum endotoxin, and MRS were performed in all patients at baseline and at 3 months and 20 patients of cirrhosis without MHE and 20 healthy controls.

RESULTS

After 3 months, median arterial ammonia (69.4 vs 52.7 mcg/dL), TNF-α (26.6 vs 22 pg/mL), IL-6 (17.6 vs 12.4 pg/mL), IL-18 (42.5 vs 29 pg/mL), and serum endotoxin (0.68 vs 0.43 EU/mL) significantly decreased in Gr. MHE-L compared with baseline (P < 0.0001), while no change was seen in Gr. MHE-NL patients. On MRS, compared with patients of cirrhosis without MHE, mI and cho were significantly lower (P < 0.001) and glutamine (Glx) was significantly higher in both MHE groups (P < 0.001). After 3 months, mI and cho increased and Glx decreased significantly in Gr. MHE-L (P < 0.001), without changes in Gr. MHE-NL patients. Psychometric hepatic encephalopathic score (PHES) correlated well with arterial ammonia, TNF-α, IL-6, IL-18, serum endotoxin, and metabolic parameters on MRS.

CONCLUSIONS

Arterial ammonia, inflammatory mediators (TNF-α, IL-6, IL-18), and serum endotoxin reduce and MRS abnormalities improve after treatment with lactulose in patients with MHE.

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.

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.

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.

[Cognitive deterioration after cardiosurgery]

Over 100,000 heart surgeries are performed in Germany annually. Although severe neurological complications like ischaemic strokes have meanwhile become rare occurrences, subtle neuropsychological changes are still frequently recognized after major heart surgeries. The hitherto unsolved problem of postoperative cognitive decline (POCD) is portrayed in this article. Multifactorial aetiologies including microembolism and preoperative risk factors are supposed to play a significant role in POCD. A variety of neuroprotective strategies such as intraoperative microemboli filtration have been suggested to minimize cerebral risks. The utility of neuroprotective methods has recently been verified in randomized studies.

Screening for minimal hepatic encephalopathy in asymptomatic drivers with liver cirrhosis

BACKGROUND AND STUDY AIMS

Minimal hepatic encephalopathy (MHE) represents a part of the spectrum of hepatic encephalopathy (HE). It can have a far-reaching impact on quality and ability to function in daily life and may progress to overt HE. This study was designed to screen for MHE in drivers with liver cirrhosis in Mansoura, a city in the Nile delta in Egypt.

PATIENTS AND METHODS

A total of 174 consecutive drivers with positive serology for viral markers and cirrhosis were screened for MHE. Questionnaires and standard psychometric tests and well-informed consent were performed at the same setting. The diagnosis of MHE was made when one or both symbol digit test (SDT) and number connection test (NCT) appeared abnormal. Beck's inventory and Mini Mental State Examination questionnaires were performed for those diagnosed as MHE. After overnight fasting, venous blood samples were taken for haematologic tests and routine liver function tests by conventional methods. Arterial ammonia was also measured.

RESULTS

A total of 66 patients showed evidence for MHE out of 139 patients who fulfilled the inclusion criteria. No significant differences were present, apart from a significantly elevated arterial ammonia level (p-value <0.001) and a bad self-reported driving history (p<0.05) in the MHE-positive group when compared with the MHE-negative group. Multivariate logistic regression revealed that advanced Child-Pugh grade (p<0.001), hepatitis B virus (HBV)-related aetiology (p<0.001) and smoking are significant risk factors for MHE. MHE is significantly commoner among Child-Pugh C patients (p<0.05) when compared with the other Child-Pugh grades.

CONCLUSION

Our data revealed a high prevalence of MHE (47%) among Egyptian drivers with liver cirrhosis. It is hence recommended to include the driving history as well as regular pencil-paper standard psychometric testing in evaluating those at risk, especially in the outpatient setting, for early detection and proper management.

Rifaximin improves driving simulator performance in a randomized trial of patients with minimal hepatic encephalopathy

BACKGROUND & AIMS

Patients with cirrhosis and minimal hepatic encephalopathy (MHE) have driving difficulties but the effects of therapy on driving performance is unclear. We evaluated whether performance on a driving simulator improves in patients with MHE after treatment with rifaximin.

METHODS

Patients with MHE who were current drivers were randomly assigned to placebo or rifaximin groups and followed up for 8 weeks (n = 42). Patients underwent driving simulation (driving and navigation tasks) at the start (baseline) and end of the study. We evaluated patients' cognitive abilities, quality of life (using the Sickness Impact Profile), serum levels of ammonia, levels of inflammatory cytokines, and model for end-stage-liver disease scores. The primary outcome was the percentage of patients who improved in driving performance, calculated as follows: total driving errors = speeding + illegal turns + collisions.

RESULTS

Over the 8-week study period, patients given rifaximin made significantly greater improvements than those given placebo in avoiding total driving errors (76% vs 31%; P = .013), speeding (81% vs 33%; P = .005), and illegal turns (62% vs 19%; P = .01). Of patients given rifaximin, 91% improved their cognitive performance, compared with 61% of patients given placebo (P = .01); they also made improvements in the psychosocial dimension of the Sickness Impact Profile compared with the placebo group (P = .04). Adherence to the assigned drug averaged 92%. Neither group had changes in ammonia levels or model for end-stage-liver disease scores, but patients in the rifaximin group had increased levels of the anti-inflammatory cytokine interleukin-10.

CONCLUSIONS

Patients with MHE significantly improve driving simulator performance after treatment with rifaximin, compared with placebo.

Legal ramifications for physicians of patients who drive with hepatic encephalopathy

BACKGROUND & AIMS

Hepatic encephalopathy, a spectrum of neuropsychiatric abnormalities that can occur in patients with liver dysfunction, negatively affects driving performance, but no study has examined legal ramifications. We studied state requirements for reporting hepatic encephalopathy and investigated whether lawsuits have been completed against physicians or patients for motor vehicle accidents that were related to hepatic encephalopathy.

METHODS

We contacted motor vehicle departments from all 50 states and examined motor vehicle codes and legal databases to search for hepatic encephalopathy-related lawsuits.

RESULTS

Definitions of a medically impaired driver varied considerably. No state specifically mentioned hepatic encephalopathy or patients with advanced liver disease. Only 6 (12%) of the states had mandatory reporting laws for drivers who have medical impairment, and 25 of the remaining 44 states (57%) provided legal immunity to physicians for reporting such patients. The legal databases did not contain any cases against physicians for failure to warn against driving or diagnose hepatic encephalopathy that resulted in an accident. There were no lawsuits identified against an encephalopathic patient for causing a motor vehicle accident.

CONCLUSIONS

Only 6 states require physicians to report drivers with medical impairments. Hepatic encephalopathy is not specifically addressed in any state vehicle code. There are no completed lawsuits against physicians or patients for motor vehicle accidents associated with driving impairment from hepatic encephalopathy. In the absence of definitive laws, the onus of responsibility for identifying potentially hazardous drivers might still lie with the physician; physicians should carefully evaluate patients for driving abilities.

Hepatoprotective and behavioral effects of jigrine in galactosamine-induced hepatopathy in rats

The hepatoprotective activity of jigrine, a polypharmaceutical herbal formulation, at a dose of 1 mL/kg/day p.o. was evaluated against galactosamine (400 mg/kg b.wt.)-induced hepatopathy in rats. Biochemical parameters such as alanine trasaminase (ALT), alkaline phosphatase (ALP), and bilirubin were estimated to assess liver function. Jigrine was also evaluated for its effect on the possible behavioral alterations secondary to liver damage produced by galactosamine (d-Gal) administration in rats. The d-Gal-induced elevation in serum levels of ALT, ALP, and bilirubin was significantly reduced (p values <0.01, <0.01, and <0.05, respectively) in jigrine- and silymarin-pretreated rats. Jigrine pretreatment also exhibited beneficial effects on d-Gal-induced behavioral abnormalities in rats. Silymarin (25 mg/kg/day p.o.) was used as reference standard. The biochemical observations were supplemented with histopathological examination of rat liver sections. Histopathological evaluation showed marked improvement in the livers of jigrine- and silymarin-treated animals.

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.

Diagnostic and prognostic values of critical flicker frequency determination as new diagnostic tool for objective HE evaluation in patients undergoing TIPS implantation

OBJECTIVES

The diagnostic and prognostic value of critical flicker frequency (CFF) analysis for assessment of severity and dynamics of hepatic encephalopathy (HE) was studied before and after implantation of a transjugular intrahepatic portosystemic shunt (TIPS).

BASIC METHODS

Sixty-three cirrhotic patients were retrospectively analyzed for the consequences of TIPS implantation. Thirty-one cirrhotic patients without TIPS implantation served as age-matched, sex-matched, Child-Pugh-matched controls. CFF and computer psychometric tests as objective test parameters of HE-severity were evaluated for analysis of visual discrimination ability, general arousal and cognitive function. Kaplan-Meier method and Cox proportional hazards regression model were used for analysis of prognostic significances.

MAIN RESULTS

In the control group, HE-severity was stable during the observation period (442+/-428 days) with minimal changes in CFF (-0.1+/-1.9 Hz). In the intervention group, TIPS implantation had no effect on HE-severity in 44% of the patients and CFF shifted by only 0.01+/-1.5 Hz. Thirty-five and 21% of the patients experienced an aggravation or improvement of HE after TIPS implantation, respectively. In HE improvers CFF increased by 3.3+/-2.3 Hz and decreased by 3.5+/-1.5 Hz in those experiencing an aggravation of HE-severity. Univariate analysis showed that overall survival in the study population inversely correlated with HE-severity and serum alkaline phosphatase activity and positively correlated with serum sodium, albumin and CFF. Serum albumin, alkaline phosphatase levels and CFF were independent predictors of survival in a multivariate Cox regression analysis.

CONCLUSION

The data show that pre-TIPS HE does not predict post-TIPS encephalopathy. Otherwise, CFF can reliably pick up the evolution of HE-severity after TIPS implantation. Low pre-TIPS CFF is indicative for a poor prognosis and may help to identify transplant candidates without delay.

Hepatic encephalopathy and fitness to drive

BACKGROUND & AIMS

Low-grade hepatic encephalopathy (HE) may impair fitness to drive. Driving deficits have not yet been characterized, and their relation to psychometric test results is unclear.

METHODS

Fifty-one cirrhotic patients and 48 age-matched controls underwent real driving in a multiple sensor and camera-equipped car, laboratory and "in-car" computer psychometry, and driving instructor's assessment.

RESULTS

Ten cirrhotic patients had no hepatic encephalopathy (HE0); 27 and 14 patients suffered from minimal HE (mHE) and overt HE grade I (oHE), respectively. During real driving, mHE and oHE patients showed significantly more violations of in-lane keeping, reduced break use, prolonged reaction times, and diminished stress tolerance compared with control or cirrhotic HE0 patients. In a self-evaluation questionnaire, mHE and oHE, but not the HE0, patients strongly overestimated their driving abilities. According to the driving instructor's assessment, 75%, 48%, and 39% of the patients with HE0, mHE, and oHE, respectively, were fit to drive, compared with 87% in the control group. Driving deficits in oHE patients were largely due to cognitive defects and prolonged reaction times, whereas, in mHE patients, mistakes and attention deficits predominated. Computer psychometric test results worsened with HE severity and age, whereas real driving was age independent. In 25 out of 94 patients, discordant results for driving fitness were obtained (driving instructor's assessment vs computer psychometry); in mHE and oHE patients, the concordance rates were only 62% and 64%, respectively.

CONCLUSIONS

Despite significant driving deficits, HE patients overestimate their driving abilities. The presence of mHE does not necessarily predict driving unfitness, and computer-based testings cannot reliably predict driving fitness.

Minimal hepatic encephalopathy is associated with motor vehicle crashes: the reality beyond the driving test

Patients with minimal hepatic encephalopathy (MHE) have impaired driving skills, but association of MHE with motor vehicle crashes is unclear. Standard psychometric tests (SPT) or inhibitory control test (ICT) can be used to diagnose MHE. The aim was to determine the association of MHE with crashes and traffic violations over the preceding year and on 1-year follow-up. Patients with cirrhosis were diagnosed with MHE by ICT (MHEICT) and SPT (MHESPT). Self and department-of-transportation (DOT)-reports were used to determine crashes and violations over the preceding year. Agreement between self and DOT-reports was analyzed. Patients then underwent 1-year follow-up for crash/violation occurrence. Crashes in those with/without MHEICT and MHESPT were compared. 167 patients with cirrhosis had DOT-reports, of which 120 also had self-reports. A significantly higher proportion of MHEICT patients with cirrhosis experienced crashes in the preceding year compared to those without MHE by self-report (17% vs 0.0%, P = 0.0004) and DOT-reports (17% vs 3%, P = 0.004, relative risk: 5.77). SPT did not differentiate between those with/without crashes. A significantly higher proportion of patients with crashes had MHEICT compared to MHESPT, both self-reported (100% vs 50%, P = 0.03) and DOT-reported (89% vs 44%, P = 0.01). There was excellent agreement between self and DOT-reports for crashes and violations (Kappa 0.90 and 0.80). 109 patients were followed prospectively. MHEICT patients had a significantly higher future crashes/violations compared to those without (22% vs 7%, P = 0.03) but MHESPT did not. MHEICT (Odds ratio: 4.51) and prior year crash/violation (Odds ratio: 2.96) were significantly associated with future crash/violation occurrence.

CONCLUSION

Patients with cirrhosis and MHEICT have a significantly higher crash rate over the preceding year and on prospective follow-up compared to patients without MHE. ICT, but not SPT performance is significantly associated with prior and future crashes and violations. There was an excellent agreement between self- and DOT-reports.

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.

Hepatic encephalopathy: pathophysiology and emerging therapies

Hepatic encephalopathy is characterized by neuropsychiatric abnormalities in patients with liver failure. Severe hepatic encephalopathy is an indication for liver transplantation as it portends poor outcome. Treatment of hepatic encephalopathy involves correction of precipitating factors such as sepsis, gastrointestinal bleeding, medications, and electrolyte imbalance. Effective therapies include lactulose and antibiotics such as neomycin, metronidazole, and rifaximin.

Neuropsychological assessment of hepatic encephalopathy: ISHEN practice guidelines

Low-grade or minimal hepatic encephalopathy (MHE) is characterised by relatively mild neurocognitive impairments, and occurs in a substantial percentage of patients with liver disease. The presence of MHE is associated with a significant compromise of quality of life, is predictive of the onset of overt hepatic encephalopathy and is associated with a poorer prognosis for outcome. Early identification and treatment of MHE can improve quality of life and may prevent the onset of overt encephalopathy, but to date, there has been little agreement regarding the optimum method for detecting MHE. The International Society on Hepatic Encephalopathy and Nitrogen Metabolism convened a group of experts for the purpose of reviewing available data and making recommendations for a standardised approach for neuropsychological assessment of patients with liver disease who are at risk of MHE. Specific recommendations are presented, along with a proposed methodology for further refining these assessment procedures through prospective research.

Minimal hepatic encephalopathy matters in daily life

Minimal hepatic encephalopathy is a neuro-cognitive dysfunction which occurs in an epidemic proportion of cirrhotic patients, estimated as high as 80% of the population tested. It is characterized by a specific, complex cognitive dysfunction which is independent of sleep dysfunction or problems with overall intelligence. Although named “minimal”, minimal hepatic encephalopathy (MHE) can have a far-reaching impact on quality of life, ability to function in daily life and progression to overt hepatic encephalopathy. Importantly, MHE has a profound negative impact on the ability to drive a car and may be a significant factor behind motor vehicle accidents. A crucial aspect of the clinical care of MHE patients is their driving history, which is often ignored in routine care and can add a vital dimension to the overall disease assessment. Driving history should be an integral part of care in patients with MHE. The lack of specific signs and symptoms, the preserved communication skills and lack of insight make MHE a difficult condition to diagnose. Diagnostic strategies for MHE abound, but are usually limited by financial, normative or time constraints. Recent studies into the inhibitory control and critical flicker frequency tests are encouraging since these tests can increase the rates of MHE diagnosis without requiring a psychologist. Although testing for MHE and subsequent therapy is not standard of care at this time, it is important to consider this in cirrhotics in order to improve their ability to live their life to the fullest.