Excessive daytime sleepiness and hepatic encephalopathy: it is worth asking

The Sleepiness-Depression Link in Obstructive Sleep Apnea: Preliminary Results on the Mediation of Impulsivity

BACKGROUND

Emotional impulsivity has been found to be relevant in explaining the association between sleep problems and depressive symptoms, suggesting the potential role of impulsivity as a key underlying mechanism of this link. The objective of this study was to take a preliminary step in understanding the mediating role of impulsivity in the relation between excessive daytime sleepiness (EDS) and depression in patients with obstructive sleep apnea syndrome (OSAS) and to compare psychological and demographic characteristics between different levels of daytime sleepiness.

METHODS

A total of 138 patients with OSAS underwent polygraphic cardiorespiratory monitoring and completed a series of questionnaires investigating perceived sleepiness, depression, impulsivity, and other psychological characteristics. A mediational model was tested in order to assess whether impulsivity mediated the relation between sleepiness and depressive symptoms while controlling for the effects of age, sex, BMI, and oxygen saturation parameters.

RESULTS

the mediation model showed that there was a significant indirect effect of impulsivity in the sleepiness-depression link (αβ = 0.084 [0.0243-0.1617]).

CONCLUSIONS

The here-presented results showed that the sleepiness-depression link is not direct as previous studies asserted, but instead it may be better explained by impulsivity. Research and practical implications are discussed.

Primary Prophylaxis of Overt Hepatic Encephalopathy: Is It Time to Consider It?

Hepatic encephalopathy (HE) represents one of the most frequent complications of liver cirrhosis and one of the most debilitating clinical manifestations of liver disease due to the accumulation of toxic substances in the blood and central nervous system [...].

Targets and study design for symptom-focused trials aimed at patients with cirrhosis: An expert consensus

BACKGROUND

Symptom-focused trials are critically needed for patients with cirrhosis. However, this work would benefit from standard processes and validated measures.

METHODS

A writing group was formed among hepatologists, nurses, palliative care providers, pharmacists, and clinical trial experts focused on symptom management in patients with cirrhosis to define the key (1) components of trial design, (2) symptom targets, (3) measurement, and (4) outcomes for each target. From July 2022 to January 2023, panelists participated in an iterative process of developing and arriving at a consensus for each component. The goal was to provide consensus definitions that can be operationalized in future clinical trials, including for patients with cirrhosis.

RESULTS

The panel reached a consensus on key reporting features for clinical trials, along with considerations for study design. Nine key symptom targets (muscle cramps, pruritus, pain, fatigue, sexual dysfunction, sleep disorders, depression and anxiety, nausea/vomiting, and dyspnea/breathlessness) were identified. The panel selected instruments that can be considered for clinical trials based on psychometric validation and previous experience. The panel identified ongoing needs, including instrument validation, safety data, evidence about non-pharmacologic interventions, and comparative effectiveness studies.

CONCLUSION

This expert panel identified key design, reporting, and measurement elements to standardize processes and measures in future symptom-focused clinical trials in the context of cirrhosis.

The Glymphatic System May Play a Vital Role in the Pathogenesis of Hepatic Encephalopathy: A Narrative Review

Hepatic encephalopathy (HE) is a neurological complication of liver disease resulting in cognitive, psychiatric, and motor symptoms. Although hyperammonemia is a key factor in the pathogenesis of HE, several other factors have recently been discovered. Among these, the impairment of a highly organized perivascular network known as the glymphatic pathway seems to be involved in the progression of some neurological complications due to the accumulation of misfolded proteins and waste substances in the brain interstitial fluids (ISF). The glymphatic system plays an important role in the clearance of brain metabolic derivatives and prevents aggregation of neurotoxic agents in the brain ISF. Impairment of it will result in aggravated accumulation of neurotoxic agents in the brain ISF. This could also be the case in patients with liver failure complicated by HE. Indeed, accumulation of some metabolic by-products and agents such as ammonia, glutamine, glutamate, and aromatic amino acids has been reported in the human brain ISF using microdialysis technique is attributed to worsening of HE and correlates with brain edema. Furthermore, it has been reported that the glymphatic system is impaired in the olfactory bulb, prefrontal cortex, and hippocampus in an experimental model of HE. In this review, we discuss different factors that may affect the function of the glymphatic pathways and how these changes may be involved in HE.

Circadian rhythms and the liver

This narrative review briefly describes the mammalian circadian timing system, the specific features of the liver clock, also by comparison with other peripheral clocks, the role of the liver clock in the preparation of food intake, and its relationship with energy metabolism. It then goes on to provide a chronobiological perspective of the pathophysiology and management of several types of liver disease, with a particular focus on metabolic-associated fatty liver disease (MAFLD), decompensated cirrhosis and liver transplantation. Finally, it provides some insight into the potential contribution of circadian principles and circadian hygiene practices in preventing MAFLD, improving the prognosis of advanced liver disease and modulating liver transplantation outcomes.

Systematic Review and Meta-Analysis on the Effects of Lactulose and Rifaximin on Patient-Reported Outcomes in Hepatic Encephalopathy

INTRODUCTION

Patients with hepatic encephalopathy (HE) suffer from significant symptoms and impaired quality of life. Improved understanding on the potential benefits of first-line HE therapies may aid patient-provider discussions regarding expected benefits of HE treatments. We aimed to perform a systematic review to assess the effects of lactulose and rifaximin on patient-reported outcomes (PROs).

METHODS

We searched MEDLINE, EMBASE, and Cochrane Library databases for randomized trials or prospective cohort studies using lactulose and/or rifaximin for the management of HE and assessing changes in PRO using PRO instruments. Physician reviewers independently reviewed titles, abstracts, and full texts and extracted data independently. We performed random-effects meta-analyses to examine the effects of lactulose and rifaximin on PROs.

RESULTS

We identified 16 studies representing 1,376 patients that met inclusion criteria. Most studies assessed treatment of covert HE. In patients with covert HE, lactulose significantly improved overall patient-reported health-related quality of life measured by the Sickness Impact Profile with an estimated pooled mean difference of 6.92 (95% confidence interval: 6.66-7.18) and showed improvements in several subscales. Conversely, rifaximin demonstrated a nonstatistically significant mean difference in the total Sickness Impact Profile of 4.76 (95% confidence interval: -4.23 to 13.76), with strong evidence of heterogeneity between these studies. Studies examining other PRO instruments showed improvements in overall health-related quality of life, social functioning, and sleep from both lactulose and rifaximin.

DISCUSSION

Patients with HE treated with lactulose or rifaximin reported improvements in important PROs. These results may inform provider-patient communication and help manage patient expectations regarding the potential benefits of HE therapies.

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.

Lack of direct association between viral hepatitis and sleep disturbances

Background

Individuals with chronic viral hepatitis are at increased risk of experiencing poor sleep quality and sleep disturbances. However, it remains unclear whether the sleep disorders associated with viral hepatitis are secondary to the comorbidities related to viral hepatitis or the direct effect of hepatitis viruses on sleep. This study investigated the direct impact of viral hepatitis B and C on sleep quality.

Methods

Individuals with viral hepatitis B or C and their healthy counterparts were recruited for the present study, and they were evaluated with the Parkinson's Disease Sleep Scale-2, the Epworth Sleepiness Scale, and the Pittsburgh Sleep Quality Index in the absence of common comorbidities associated with viral hepatitis.

Results

Neither hepatitis B nor hepatitis C was found to cause significant differences in insomnia symptoms or excessive daytime sleepiness. However, individuals with hepatitis C, but not hepatitis B, tended to be less likely to experience restlessness of the legs or arms at night.

Conclusions

This study suggests that hepatitis viruses B and C may not cause a significant impact on sleep quality and related disorders directly. Sleep disturbances in individuals with chronic viral hepatitis may instead be attributable to hepatic decompensation or the comorbid factors associated with viral hepatitis.

The effect of induced hyperammonaemia on sleep and melanopsin-mediated pupillary light response in patients with liver cirrhosis: A single-blinded randomized crossover trial

Background & aims

Sleep disturbances are related to hepatic encephalopathy and hyperammonaemia in patients with cirrhosis. The circadian rhythm is regulated by light stimulation of the retina via melanopsin-containing ganglion cells. The study aimed to investigate whether induced hyperammonaemia affects the pupillary light response and sleep efficiency in patients with cirrhosis.

Methods

The study was a single-blinded crossover trial including nine patients with cirrhosis. Sleep was evaluated by Pittsburgh Sleep Quality Index (PSQI) and monitored for twelve nights with wrist accelerometers and sleep diaries. On two experimental days, separated by one week, patients were randomized to ingest either an oral amino acid challenge (AAC) or an isocaloric glucose solution (GS). We measured pupillary light response, capillary ammonia, the Karolinska Sleepiness Scale (KSS), and two neuropsychological tests on both experimental days.

Results

The patients had poor self-assessed sleep quality. The amino acid challenge led to a significant increase in capillary ammonia and KSS. The time spent in bed sleeping after AAC was longer and with a reduced movement index compared to baseline but not different from GS. We found no difference in the pupillary light response or neuropsychiatric tests when comparing the effect of AAC with GS.

Conclusions

Patients with cirrhosis had impaired sleep quality. Induced hyperammonaemia led to increased sleepiness but had no acute effect on pupillary light response or the neuropsychiatric tests.

Trial registration

Registration number: NCT04771104.

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.

Assessment of Sleep among Patients with Chronic Liver Disease: Association with Quality of Life

The present study aims to assess the sleep characteristics and health-related quality of life (HRQOL) among patients with chronic liver diseases (CLDs), as well as the relationship between them. We conducted a prospective cross-sectional study, over a period of eight months, on patients with CLDs. Sleep was assessed by subjective tools (self-reported validated questionnaires), semi-objective methods (actigraphy), and HRQOL by using the 36-Item Short Form Survey (SF-36) and Chronic Liver Disease Questionnaire (CLDQ). The results indicated that 48.21% of patients with CLDs had a mean Pittsburgh Sleep Quality Index (PSQI) score higher than five, suggestive of poor sleep; 39.29% of patients had a mean Epworth Sleepiness Scale (ESS) score ≥11, indicative of daytime sleepiness. Actigraphy monitoring showed that patients with cirrhosis had significantly more delayed bedtime hours and get-up hours, more awakenings, and more reduced sleep efficacy when compared to pre-cirrhotics. The CLDQ and SF-36 questionnaire scores were significantly lower in cirrhotics compared to pre-cirrhotics within each domain. Moreover, we identified significant correlations between the variables from each questionnaire, referring to HRQOL and sleep parameters. In conclusion, sleep disturbances are commonly encountered among patients with CLDs and are associated with impaired HRQOL. This is the first study in Romania that assesses sleep by actigraphy in a cohort of patients with different stages of CLD.

New Therapies of Liver Diseases: Hepatic Encephalopathy

Hepatic encephalopathy (HE) is a common complication of advanced liver disease which has profound implications in terms of the patients’ ability to fulfil their family and social roles, to drive and to provide for themselves. Recurrent and persistent HE is still a serious management challenge, translating into a significant burden for patients and their families, health services and society at large. The past few years have been characterized by significantly more attention towards HE and its implications; its definition has been refined and a small number of new drugs/alternative management strategies have become available, while others are underway. In this narrative review we summarize them in a pragmatic and hopefully useful fashion.

Rest-activity rhythm disturbance in liver cirrhosis and association with cognitive impairment

Cognitive impairment and disturbed sleep-wake rhythms are disabling complications of liver cirrhosis, yet there is limited understanding of how they are related. We tested the hypothesis that alterations of sleep, rest-activity, and light exposure patterns are associated with worse cognition in cirrhosis. A total of 54 ambulatory adult patients with cirrhosis and 41 age-/gender-matched healthy controls wore wrist actigraphy for rest-activity and light measurements and completed Patient-Reported Outcomes Measurement Information System sleep instruments for self-reported sleep quality. We used standard nonparametric descriptors to characterize rest-activity and light patterns, and wake after sleep onset and sleep efficiency to assess objective sleep quality. The NIH Toolbox cognition battery was used for objective cognitive evaluation using T-scores from a demographically adjusted population reference. Spearman's correlation and multivariable models were used to explore associations between measures of cognition, sleep, rest-activity, and light. Cognition was significantly impaired in cirrhosis patients. Sleep quality was worse in cirrhosis patients by subjective and objective measures compared with controls. Cirrhosis patients exhibited fragmented and dampened rest-activity rhythms, lower daytime and higher nighttime light exposure compared with controls. Worse working memory and processing speed was associated with lower daytime activity level, higher rest-activity fragmentation, lower day-to-day stability, and greater nocturnal light exposure. No association was found between cognition and sleep quality. Rest-activity fragmentation and abnormal light exposure patterns are common in patients with liver disease and are associated with the severity of cognitive impairment. Further research is needed to investigate the effects of timed bright light and exercise intervention on cognitive function in patients with liver disease.

The role of astrocytes in generating circadian rhythmicity in health and disease

Evidence is accumulating that the mammalian circadian clock system is considerably more complex than previously believed, also in terms of the cell types that actually contribute to generating the oscillation within the master clock, in the suprachiasmatic nuclei of the hypothalamus. Here we review the evidence that has lead to the identification of a bona fide astrocytic circadian clock, and that of the potential contribution of such clock to the generation of circadian and seasonal rhythmicity in health and in neurodegenerative disorders. Finally, we speculate on the role of the astrocytic clock in determining some of the clinical features of hepatic encephalopathy, a reversible neuropsychiatric syndrome associated with advanced liver disease, which is characterized by transient, profound morphological and functional astrocytic abnormalities, in the absence of significant, structural neuronal changes.

Comprehensive Overview of Sleep Disorders in Patients with Chronic Liver Disease

The impact of sleep disorders (SDs) on patients with chronic liver diseases (CLD) is tremendous. SDs are frequently encountered among these patients and interfere with their quality of life. This review aims to present the data available so far about the prevalence, phenotypes, and proposed pathophysiological mechanisms of SDs in CLD. Moreover, we proposed to search the literature regarding the most reliable methods to assess SDs and the possible therapeutic options in patients with CLD. The main results of this review show that when it comes to prevalence, the percentages reported vary widely between studies performed among populations from the USA or Europe and those coming from Asian countries. Furthermore, it has been proven that SDs may also be present in the absence of neurocognitive disorders attributable to hepatic encephalopathy (HE), which contradicts traditional suppositions where SDs were considered part of the clinical scenario of HE. Currently, there are no specific recommendations or protocols to assess SDs in CLD patients and data about the therapeutic management are limited. Taking into consideration their impact, a protocol for diagnosing and managing SDs should be developed and included in the daily practice of hepatologists.

Prevalence of and Factors Associated with Sleep-Wake Abnormalities in Patients with Cirrhosis

BACKGROUND & AIMS

Sleep-wake abnormalities [poor nighttime sleep and excessive daytime sleepiness (EDS)] are common in patients with cirrhosis. The aim of this study was to assess the prevalence of sleep-wake abnormalities and clinical factors associated with these abnormalities in a group of patients with cirrhosis.

METHODS

1098 patients with cirrhosis [Child Turcotte Pugh (CTP) class A, 22.2%; CTP class B, 29.2% and CTP class C, 48.6%], with either no ascites or mild ascites controlled on diuretics, and no history of or current overt hepatic encephalopathy were included in the study.

RESULTS

Poor nighttime sleep and EDS were found in 569 (51.8%) and 489 (44.5%) patients respectively. On multivariate analysis, factors associated with poor nighttime sleep were CTP class C (vs. class A), presence of minimal hepatic encephalopathy (MHE), intermediate or evening type of diurnal preference category (vs. morning type), high risk for obstructive sleep apnea (OSA), diuretic use, presence of major depression, and presence of generalized anxiety disorder (GAD). Factors associated with EDS on multivariate analysis were CTP class B and C (vs. class A), intermediate or evening type of diurnal preference category (vs. morning type), high risk for OSA, presence of major depression, and presence of GAD.

CONCLUSIONS

Sleep-wake abnormalities are common in patients with cirrhosis. CTP status, diurnal preference chronotype, risk of OSA, major depression and GAD are associated with both poor nighttime sleep and EDS. MHE and diuretic use are associated with poor nighttime sleep, but not with EDS.

Sleep disorder in patients with chronic liver disease: a narrative review

Sleep disturbance is a common feature of chronic liver disease (CLD) with impact on health-related quality of life; 60-80% of patients with CLD report subjective poor sleep; frequent presentations of sleep disturbance include insomnia, reduced sleep efficiency, increased sleep latency, reduced time in rapid eye movement (REM) sleep, restless leg syndrome and excessive daytime sleepiness (EDS). Key contributors to sleep disturbance include hepatic encephalopathy (HE) and circadian rhythm imbalance due to altered melatonin metabolism. Specific conditions causing CLD, such as non-alcoholic fatty liver disease (NAFLD), chronic viral hepatitis and primary biliary cholangitis (PBC) result in different types of sleep disturbance, and the treatment of these conditions can often also lead to sleep disturbance. There are currently limited management options for sleep disturbance in CLD. Obstructive sleep apnoea (OSA) is a common condition that causes chronic intermittent hypoxia due to airway collapse during sleep. This chronic intermittent hypoxia appears to contribute to the development of NAFLD. The presence of reactive oxygen species and the overexpression of hypoxia inducible factor 1-alpha secondary to hypoxia may be responsible for the second 'hit' of the 'two-hit' hypothesis of NAFLD. Treatment of the intermittent hypoxia with continuous positive airway pressure therapy has limited efficacy against liver dysfunction. There remain many outstanding areas of investigation in the management of sleep disturbance in CLD, and of liver dysfunction in OSA.

Impact of Hepatic Encephalopathy in Cirrhosis on Quality-of-Life Issues

Hepatic encephalopathy (HE) has a major impact on health-related quality of life (HRQOL) in patients, which has clinical and psychosocial consequences. HRQOL in cirrhosis has been measured by generic and liver-specific instruments, with most studies indicating a negative impact of HE. HRQOL abnormalities span daily functioning, sleep–wake cycle changes, and the ability to work. Of these, sleep–wake cycle changes have a major effect on HRQOL, which remains challenging to treat. The personal effect of HRQOL is modulated by the presence of HE, the etiology of cirrhosis, and cognitive reserve. Patients with higher cognitive reserve are able to tolerate HE and its impact on HRQOL better than those with a poor cognitive reserve. The impact of HRQOL impairment is felt by patients (higher mortality and poor daily functioning), as well as by caregivers and families. Caregivers of patients with HE bear a major financial and psychological burden, which may affect their personal health and longevity.

Symptom prevalence and quality of life of patients with end-stage liver disease: A systematic review and meta-analysis

BACKGROUND:

End-stage liver disease is a common cause of morbidity and mortality worldwide, yet little is known about its symptomatology and impact on health-related quality of life.

AIM:

To describe symptom prevalence and health-related quality of life of patients with end-stage liver disease to improve care.

DESIGN:

Systematic review.

DATA SOURCES:

We searched eight electronic databases from January 1980 to June 2018 for studies investigating symptom prevalence or health-related quality of life of adult patients with end-stage liver disease. No language restrictions were applied. Meta-analyses were performed where appropriate.

RESULTS:

We included 80 studies: 35 assessing symptom prevalence, 41 assessing health-related quality of life, and 4 both. The instruments assessing symptoms varied across studies. The most frequently reported symptoms were as follows: pain (prevalence range 30%–79%), breathlessness (20%–88%), muscle cramps (56%–68%), sleep disturbance (insomnia 26%–77%, daytime sleepiness 29.5%–71%), and psychological symptoms (depression 4.5%–64%, anxiety 14%–45%). Erectile dysfunction was prevalent (53%–93%) in men. The health-related quality of life of patients with end-stage liver disease was significantly impaired when compared to healthy controls or patients with chronic liver disease. Compared with compensated cirrhosis, decompensation led to significant worsening of both components of the 36-Item Short Form Survey although to a larger degree for the Physical Component Summary score (decrease from average 6.4 (95% confidence interval: 4.0–8.8); p < 0.001) than for the Mental Component Summary score (4.5 (95% confidence interval: 2.4–6.6); p < 0.001).

CONCLUSION:

The symptom prevalence of patients with end-stage liver disease resembled that of patients with other advanced conditions. Given the diversity of symptoms and significantly impaired health-related quality of life, multidisciplinary approach and timely intervention are crucial.

Sleep disturbances in patients with liver cirrhosis: prevalence, impact, and management challenges

Sleep-wake disturbances are common in liver cirrhosis and associated with impaired quality of life. The most common abnormalities are insomnia (difficulties falling asleep and maintaining sleep, or unrefreshing sleep), excessive daytime sleepiness, and sleep-wake inversion (disturbances of circadian rhythmicity). The underlying pathophysiological mechanisms for sleep disturbances in cirrhosis are complex and may include disturbed metabolism of melatonin and glucose, alterations in thermoregulation, and altered ghrelin secretion profiles. Sleep-wake abnormalities are related to the presence of hepatic encephalopathy (HE) and improvement in sleep parameters can be observed when HE is properly managed. A few non-specific treatments for sleep-wake abnormalities have been tried with encouraging results for hydroxyzine and modafinil. However, due to the potential for medication toxicity in these disabled patients, further studies are needed to address the potential role of non-drug therapies in this population (eg, cognitive behavioral therapy, mindfulness, yoga) that have demonstrated usefulness in insomnia disorders.

Assessment and Management of Sleep Disturbance in Cirrhosis

Purpose of Review

This review presents an in-depth overview of the sleep–wake phenotype of patients with cirrhosis, together with available pharmacological and non-pharmacological treatment strategies. A set of simple, practical recommendations is also provided.

Recent Findings

The understanding of the pathophysiology of sleep disorders in this patient population has improved over the past decade, especially in relation to the interplay between homeostatic and circadian sleep regulation. In addition, new tools have been utilised for both screening and in-depth investigation of the sleep–wake profile of these patients. Finally, a number of studies have evaluated the efficacy of novel treatment strategies, often with encouraging results.

Summary

Since sleep disturbances are common in patients with cirrhosis, more so than in patients with other chronic diseases of similar severity, their assessment should become routine hepatological practice, along with the initiation of adequate treatment.

Abnormalities in the 24-hour rhythm of skin temperature in cirrhosis: Sleep-wake and general clinical implications

BACKGROUND & AIMS

Sleep preparation/onset are associated with peripheral vasodilatation and a decrease in body temperature. The hyperdynamic syndrome exhibited by patients with cirrhosis may impinge on sleep preparation, thus contributing to their difficulties falling asleep. The aim of this study was the assessment of skin temperature, in relation to sleep-wake patterns, in patients with cirrhosis.

METHODS

Fifty-three subjects were initially recruited, and 46 completed the study. Of the final 46, 12 were outpatients with cirrhosis, 13 inpatients with cirrhosis, 11 inpatients without cirrhosis and 10 healthy volunteers. All underwent baseline sleep-wake evaluation and blood sampling for inflammatory markers and morning melatonin levels. Distal/proximal skin temperature and their gradient (DPG) were recorded for 24 hours by a wireless device. Over this period subjects kept a sleep-wake diary.

RESULTS

Inpatients with cirrhosis slept significantly less well than the other groups. Inpatients and outpatients with cirrhosis had higher proximal temperature and blunted rhythmicity compared to the other groups. Inpatients with/without cirrhosis had higher distal temperature values and blunted rhythmicity compared to the other groups. Inpatients and outpatients with cirrhosis had significantly lower DPG values compared to the other groups, and DPG reached near-zero values several hours later. Significant correlations were observed between temperature and sleep-wake variables and inflammatory markers.

CONCLUSIONS

Alterations of distal/proximal skin temperature, their gradient and their time-course were observed in patients with cirrhosis, which may contribute to their sleep disturbances.

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.

Vigilance and wake EEG architecture in simulated hyperammonaemia: a pilot study on the effects of L-Ornithine-L-Aspartate (LOLA) and caffeine

Hyperammonaemia/mild hepatic encephalopathy (HE) can be simulated by the oral administration of a so-called amino acid challenge (AAC). This study sought to assess the effects of the AAC alone and in combination with either ammonia-lowering [L-ornithine-L-aspartate (LOLA)] or vigilance-enhancing medication (caffeine). Six patients with cirrhosis (5 males; 61.3 ± 9.2 years; 5 Child A, 1 Child B) and six healthy volunteers (5 males; 49.8 ± 10.6 years) were studied between 08:00 and 19:00 on Monday of three consecutive weeks. The following indices were obtained: hourly capillary ammonia, hourly subjective sleepiness, paper & pencil/computerized psychometry and wake electroencephalography (EEG) at 12:00, i.e. at the time of the maximum expected effect of the AAC.

RESULTS

On average, patients had worse neuropsychological performance and slower EEG than healthy volunteers in all conditions but differences did not reach significance. In healthy volunteers, the post-AAC increase in capillary ammonia levels was contained by both the administration of LOLA and of caffeine (significant differences between 10:00 and 14:00 h). The administration of caffeine also resulted in a reduction in subjective sleepiness and in the amplitude of the EEG on several frontal/temporal-occipital sites (p < 0.05; paired t-test). Changes in ammonia levels, subjective sleepiness and the EEG in the three conditions were less obvious in patients. In conclusion, both LOLA and caffeine contained the AAC-induced increase in capillary ammonia, especially in healthy volunteers. Caffeine also counteracted the AAC effects on sleepiness/EEG amplitude. The association of ammonia-lowering and vigilance-enhancing medication in the management of HE is worthy of further study.

Managing Sleep Disturbances in Cirrhosis

Sleep disturbances, particularly daytime sleepiness and insomnia, are common problems reported by patients suffering from liver cirrhosis. Poor sleep negatively impacts patients' quality of life and cognitive functions and increases mortality. Although sleep disturbances can be an early sign of hepatic encephalopathy (HE), many patients without HE still complain of poor quality sleep. The pathophysiology of these disturbances is not fully understood but is believed to be linked to impaired hepatic melatonin metabolism. This paper provides an overview for the clinician of common comorbidities contributing to poor sleep in patients with liver disease, mainly restless leg syndrome and obstructive sleep apnea. It discusses nondrug and pharmacologic treatment options in these patients, such as the use of light therapy and histamine (H1) blockers.

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.

Hepatic encephalopathy and sleepiness: an interesting connection?

Sleep-wake abnormalities in patients with cirrhosis have been traditionally associated with hepatic encephalopathy (HE). In recent years, a certain amount of work has been devoted to the study of this relationship. This has lead to a modified picture, with weakening of the association between HE and poor night sleep, and the emergence of stronger links between HE and excessive daytime sleepiness. This brief review focuses on the evidence in favor of the interpretation of HE as a sleepiness syndrome, and on the diagnostic, therapeutic and social implications of such an interpretation.

Acute hyperammonaemia induces a sustained decrease in vigilance, which is modulated by caffeine

Hyperammonaemia is observed after prolonged, intense exercise, or in patients with hepatic failure. In the latter, it is associated with a set of neurological and psychiatric abnormalities termed hepatic encephalopathy.

THE AIMS OF OUR STUDY WERE

1. to measure vigilance in a condition of induced hyperammonaemia; 2. to assess whether caffeine modulates the effects of hyperammonaemia on vigilance, if any. Ten healthy volunteers (28.5 ± 5 years; 5 males) underwent three experimental sessions consisting of two-hourly measurements of capillary ammonia, subjective sleepiness (Karolinska Sleepiness Scale) and vigilance (Psychomotor Vigilance Task, PVT), in relation to the intake of breakfast (+/-coffee), an amino acid mixture which induces hyperammonaemia (amino acid challenge; AAC), and AAC+coffee (only for participants who had coffee with their standard breakfast). The AAC resulted in: 1. the expected increase in capillary ammonia levels, with highest values at approximately 4 h after the administration; 2. a significant increase in subjective sleepiness ratings; 3. a sustained increase in PVT-based reaction times. When caffeine was administered after the AAC, both subjective sleepiness and the slowing in RTs were significantly milder than in the AAC-only condition. In conclusion, acute hyperammonaemia induces an increase in subjective sleepiness and a sustained decrease in vigilance, which are attenuated by the administration of a single espresso coffee.

Prognostic benefit of the addition of a quantitative index of hepatic encephalopathy to the MELD score: the MELD-EEG

BACKGROUND & AIMS

A slowed electroencephalogram (EEG) is indicative of the presence of hepatic encephalopathy (HE). Since HE is not reflected in the MELD score and is an important prognostic parameter, we assess the prognostic benefit of the addition of an EEG-based HE index to the MELD.

METHODS

Three hundred and ninety-two patients with cirrhosis underwent EEG and automated determination of its mean dominant frequency (MDF). MELD was calculated at the time of EEG recording. Patients were monitored for up to 18 months in relation to the occurrence of death/transplantation. The prognostic value of the stand-alone/combined MELD and MDF was calculated using standard survival analysis techniques. Patients transplanted for hepatic decompensation were considered dead on the day of transplantation, those transplanted for hepatocellular carcinoma were censored. The findings were validated using a split-sample technique (reference group: n = 256; test group: n = 136). During the follow-up period, 107 patients died/were transplanted for hepatic decompensation.

RESULTS

Both MELD and MDF predicted mortality on Kaplan-Meier analysis, and both were independent predictors of mortality on a Cox model. Based on Cox regression parameters, a novel prognostic index was devised, as follows: MELD-EEG = 0.087*MELD-0.306*MDF. On ROC curve analysis, MELD-EEG had higher prognostic accuracy in predicting 12- and 18-month mortality compared to MELD (P = 0.016 and P = 0.018, respectively). In addition, it had better sensitivity and reduced the misclassification rate for given levels of specificity. On validation, no significant differences were observed between the reference/test groups.

CONCLUSIONS

The addition of an automatically obtained EEG-based index improves the prognostic accuracy of the MELD score.

Diurnal changes of critical flicker frequency in patients with liver cirrhosis and their relationship with sleep disturbances

BACKGROUND

We aimed to measure the diurnal changes of critical flicker frequency in healthy subjects and cirrhotic patients and to investigate their relationship with sleep disturbance.

METHODS

Cirrhotic patients and healthy volunteers were included. All groups completed the Pittsburgh Sleep Quality Index and a simple sleep questionnaire. Sleep disturbance was defined as a Pittsburgh Sleep Quality Index score of >5. Critical flicker frequency was measured twice a day to detect diurnal abnormalities.

RESULTS

Overall, 59 cirrhotic patients (54.2% males, Mean Age 59 ± 11 years) and 18 controls (39.9% males, Mean Age 58 ± 9 years) were included. Sleep disturbances were more common in cirrhotics (66.1%) than controls (38.9%, p<0.05). In cirrhotics, the critical flicker frequency was not related to decompensation. The nocturnal values were higher than the morning values in cirrhotics (64.4%), but not in controls (p<0.0001). Additionally, sleep disturbances were more common in cirrhotics who had higher nocturnal values (p<0.05).

CONCLUSIONS

Changes in the diurnal critical flicker frequency were observed in cirrhotics but not in controls. Sleep disturbances in cirrhotics appear to be associated with deviations of the diurnal rhythm of critical flicker frequency rather than with clinical parameters such as the clinical stages of cirrhosis and the Model For End-Stage Liver Disease and Child-Pugh scores.

Sleep-wake abnormalities in patients with cirrhosis

A considerable proportion of patients with cirrhosis exhibit insomnia, delayed sleep habits, and excessive daytime sleepiness. These have been variously attributed to hepatic encephalopathy and impaired hepatic melatonin metabolism, but the understanding of their pathophysiology remains limited and their treatment problematic. Sleep is regulated by the interaction of a homeostatic and a circadian process. The homeostatic process determines sleep propensity in relation to sleep-wake history, thus the need to sleep increases with the duration of the waking period. The circadian process, which is marked by the 24-hour rhythm of the hormone melatonin, is responsible for the alternation of high/low sleep propensity in relation to dark/light cues. Circadian sleep regulation has been studied in some depth in patients with cirrhosis, who show delays in the 24-hour melatonin rhythm, most likely in relation to reduced sensitivity to light cues. However, while melatonin abnormalities are associated with delayed sleep habits, they do not seem to offer a comprehensive explanation to the insomnia exhibited by these patients. Fewer data are available on homeostatic sleep control: it has been recently hypothesized that patients with cirrhosis and hepatic encephalopathy might be unable, due to excessive daytime sleepiness, to accumulate the need/ability to produce restorative sleep. This review will describe in some detail the features of sleep-wake disturbances in patients with cirrhosis, their mutual relationships, and those, if any, with hepatic failure/hepatic encephalopathy. A separate section will cover the available information on their pathophysiology. Finally, etiological treatment will be briefly discussed.

Correlation between degree and quality of sleep disturbance and the level of neuropsychiatric impairment in patients with liver cirrhosis

Sleep disturbances are common in patients of cirrhosis and has a significant effect on their health related quality of life (HRQOL). Thus far, no study has demonstrated a systematically studied significant correlation between the sleep disturbance observed and the neuropsychiatric impairment status of patients of cirrhosis. On the basis of PHES, we divided 100 cirrhotics into those having minimal hepatic encephalopathy (MHE) (PHES≤-5) and those not (NMHE). Now, in these MHE (n=46) and NMHE (n=54) patients, sleep disturbance was measured with Pittsburgh Sleep Quality Index (PSQI) and Epworth Sleepiness Scale (ESS) and HRQOL with SF-36(v2) questionnaire. Sixty (60 %) patients were found to be 'poor sleepers' (PSQI>5) while 38 (38 %) patients had excessive daytime sleepiness (ESS≥11). Univariate and multivariate analyses showed MHE has significant effect among 'poor sleepers' (P<0.0001) as well as on those with EDS (P<0.0001). Significant correlation existed between PHES and both the sleep parameters of PSQI (r = -0.518, P <0.0001) as well as ESS (r = -0.383, P <0.0001), implying independently strong correlation between poor cognition and the presence of night time sleep disturbance and excessive daytime sleepiness among cirrhotics. Significant correlation existed between PSQI and ESS and the various scales and component scores of SF-36(v2) signifying the negative impact of sleep disturbance on the HRQOL. In conclusion, both night time sleep disturbance and excessive daytime sleepiness have significant relation with the neuropsychiatric impairment in patients of cirrhosis and are significantly associated with the observed impairment in HRQOL.