Toward a Molecular Approach to Chronotype Assessment.

The aim of the present study was to develop a Polygenic Score-based model for molecular chronotype assessment. Questionnaire-based phenotypical chronotype assessment was used as a reference. In total, 54 extremely morning/morning (MM/M; 35 females, 39.7 ± 3.8 years) and 44 extremely evening/evening (EE/E; 20 females, 27.3 ± 7.7 years) individuals donated a buccal DNA sample for genotyping by sequencing of the entire genetic variability of 19 target genes known to be involved in circadian rhythmicity and/or sleep duration. Targeted genotyping was performed using the single primer enrichment technology and a specifically designed panel of 5526 primers. Among 2868 high-quality polymorphisms, a cross-validation approach lead to the identification of 83 chronotype predictive variants, including previously known and also novel chronotype-associated polymorphisms. A large (35 single-nucleotide polymorphisms [SNPs]) and also a small (13 SNPs) panel were obtained, both with an estimated predictive validity of approximately 80%. Potential mechanistic hypotheses for the role of some of the newly identified variants in modulating chronotype are formulated. Once validated in independent populations encompassing the whole range of chronotypes, the identified panels might become useful within the setting of both circadian public health initiatives and precision medicine.

Hepatic encephalopathy: Novel insights into classification, pathophysiology and therapy.

Hepatic encephalopathy (HE) is a frequent and serious complication of both chronic liver disease and acute liver failure. HE manifests as a wide spectrum of neuropsychiatric abnormalities, from subclinical changes (mild cognitive impairment) to marked disorientation, confusion and coma. The clinical and economic burden of HE is considerable, and it contributes greatly to impaired quality of life, morbidity and mortality. This review will critically discuss the latest classification of HE, as well as the pathogenesis and pathophysiological pathways underlying the neurological decline in patients with end-stage liver disease. In addition, management strategies, diagnostic approaches, currently available therapeutic options and novel treatment strategies are discussed.

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.

Correction: Assessment and Management of Sleep Disturbance in Cirrhosis.

[This corrects the article DOI: 10.1007/s11901-018-0390-1.].

The animal naming test: An easy tool for the assessment of hepatic encephalopathy.

Screening for hepatic encephalopathy (HE) that does not cause obvious disorientation or asterixis (minimal HE [MHE]/grade 1 HE) is important. We examined if the animal naming test (ANT1 ) (maximum number of animals listed in 1 minute) is useful in this context. In total, 208 healthy controls, 40 controls with inflammatory bowel disease, and 327 consecutive patients with cirrhosis underwent the ANT1 . Patients were tested for MHE by the psychometric HE score, and 146 were assessed by electroencephalography; 202 patients were followed up regarding the occurrence of overt HE and death. In the healthy controls, ANT1 was influenced by limited education (<8 years) and advanced age (>80 years, P < 0.001). Using an age and education adjusting procedure, the simplified ANT1 (S-ANT1 ) was obtained. An S-ANT1 of <10 animals was abnormal. Of the patients, 169 were considered unimpaired, 32 as having HE ≥grade 2, and 126 as having MHE/grade 1 HE. This group had lower S-ANT1 than unimpaired patients (12 ± 0.4 versus 16 ± 0.7, P < 0.001) and higher S-ANT1 than those with HE ≥grade 2 (4 ± 0.9). In grade 1 HE the S-ANT1 was lower than in MHE. Following receiver operating characteristic analysis (Youden's index), 15 animals produced the best discrimination between unimpaired and MHE/grade 1 HE patients. Thus, a three-level score (0 for S-ANT1 ≥15, 1 for 10 ≤ S-ANT1 < 15, 2 for S-ANT1 <10) was obtained. This score was correlated both to the psychometric HE score (P < 0.0001) and to electroencephalography (P = 0.007). By sample random split validation, both S-ANT1 and its three-level score showed prognostic value regarding the 1-year risk of overt HE and death. No inflammatory bowel disease control had S-ANT <15. CONCLUSION: The S-ANT1 is an easily obtainable measure useful for the assessment of HE. (Hepatology 2017;66:198-208).

A low-cost, user-friendly electroencephalographic recording system for the assessment of hepatic encephalopathy.

UNLABELLED: Electroencephalography (EEG) is useful to objectively diagnose/grade hepatic encephalopathy (HE) across its spectrum of severity. However, it requires expensive equipment, and hepatogastroenterologists are generally unfamiliar with its acquisition/interpretation. Recent technological advances have led to the development of low-cost, user-friendly EEG systems, allowing EEG acquisition also in settings with limited neurophysiological experience. The aim of this study was to assess the relationship between EEG parameters obtained from a standard-EEG system and from a commercial, low-cost wireless headset (light-EEG) in patients with cirrhosis and varying degrees of HE. Seventy-two patients (58 males, 61 ± 9 years) underwent clinical evaluation, the Psychometric Hepatic Encephalopathy Score (PHES), and EEG recording with both systems. Automated EEG parameters were calculated on two derivations. Strong correlations were observed between automated parameters obtained from the two EEG systems. Bland and Altman analysis indicated that the two systems provided comparable automated parameters, and agreement between classifications (normal versus abnormal EEG) based on standard-EEG and light-EEG was good (0.6 < κ < 0.8). Automated parameters such as the mean dominant frequency obtained from the light-EEG correlated significantly with the Model for End-Stage Liver Disease score (r = -0.39, P < 0.05), fasting venous ammonia levels (r = -0.41, P < 0.01), and PHES (r = -0.49, P < 0.001). Finally, significant differences in light-EEG parameters were observed in patients with varying degrees of HE. CONCLUSION: Reliable EEG parameters for HE diagnosing/grading can be obtained from a cheap, commercial, wireless headset; this may lead to more widespread use of this patient-independent tool both in routine liver practice and in the research setting. (

Where are we going? Translational research in hepatic encephalopathy.

Translational medicine, rather than being a unidirectional clinical utilization of basic research discoveries, should be a bidirectional process of cross-fertilization between basic science, medical knowledge and clinical utilization. While steps and processes differ across these branches of research, clear language and proper definitions are prerequisites for effective interaction of researchers to facilitate knowledge development. With respect to Hepatic Encephalopathy, at first glance the areas which require development are around prevention, both to reduce the risk of relapse following an episode of overt HE and to reduce the risk of the first episode of HE. In addition, shortening the duration of episodes of overt HE may also be relevant. Comparisons of treatments and combinations of treatments, acting by different but potentially synergistic mechanisms, are reasonable targets for both basic and applied research.

Assessment of 6-sulfatoxymelatonin rhythms and melatonin response to light in disease states: lessons from cirrhosis.

Circadian rhythmicity and non-visual sensitivity to light can be assessed, in healthy subjects, by measuring the rhythm of the urinary melatonin metabolite 6-sulphatoxymelatonin (aMT6s) and by determining the response of plasma melatonin to nocturnal retinal light exposure, respectively. However, the validity of these techniques has not been assessed in disease states in which disruption of the circadian rhythm is known or suspected to occur. Thus, the aims of this study were as follows: (i) to assess the reliability of circadian aMT6s profile estimates derived from 36 h versus 56 h urine collections and (ii) to test different models for calculating melatonin suppression in response to light in healthy volunteers and patients with cirrhosis. Twenty patients with biopsy-proven cirrhosis and 10 matched healthy volunteers undertook: (i) separate 36 - and 56-h urine collections, under controlled conditions, for cosinor analysis of the urinary aMT6s profile; (ii) a melatonin suppression test, comprising of a baseline night, during which subjects were woken and asked to sit in front of a switched off light sphere, and an experimental night, identically executed, except that the light sphere was switched on and the subjects were exposed to white light (4.1 × 10(14) photons/cm(2)/s) for 30 min. Alternative approaches to the calculation of melatonin suppression were taken, with/without inclusion of the baseline night. Eighteen patients and eight healthy volunteers had matched analysable 36 - and 56-h urinary samples. Cosinor analysis showed a significant fit in 88% of the remaining 56 h collections, and 48% of the remaining 36-h collections. Thus, eight patients and five healthy volunteers had matched analysable samples for cosinor analysis. In the healthy volunteers, aMT6s profile indices obtained using the 36 - and the 56-h collections did not differ significantly. In contrast, considerably more variability was observed in patients [i.e. the difference in the aMT6s peak time was 0.5 ± 1.7 h (limits of agreement: -3.9; +2.9 h)]. No difficulties were encountered in obtaining suppression estimates by use of the experimental night only. In contrast, suppression estimates obtained by use of both nights were considered inaccurate in one (11%) healthy volunteer and in 5 (28%) patients, primarily because: (i) melatonin concentrations at the beginning of light administration were significantly different on baseline and experimental night; (ii) the rise in melatonin was inconsistent on baseline night; and (iii) the shape of the rising phase of melatonin was different on baseline and experimental night. In conclusion, shorter urine collections lead to a higher number of profiles with no significant cosinor fit, and differences in cosinor indices obtained from the 36 - and 56-h collections were considerable, especially in patients. Thus, 56-h collections are probably advisable. Use of both baseline and experimental nights to calculate melatonin suppression often resulted in increased variation and confounding, due to point oscillations in melatonin concentration and lack of repeatability of the melatonin profiles on the two nights. Thus, use of the experimental night only is probably advisable.

Cost-effectiveness analysis of beta-blockers vs endoscopic surveillance in patients with cirrhosis and small varices.

AIM: To evaluate the most cost-effectiveness strategy for preventing variceal growth and bleeding in patients with cirrhosis and small esophageal varices. METHODS: A stochastic analysis based on decision trees was performed to compare the cost-effectiveness of beta-blockers therapy starting from a diagnosis of small varices (Strategy 1) with that of endoscopic surveillance followed by beta-blockers treatment when large varices are demonstrated (Strategy 2), for preventing variceal growth, bleeding and death in patients with cirrhosis and small esophageal varices. The basic nodes of the tree were gastrointestinal endoscopy, inpatient admission and treatment for bleeding, as required. All estimates were performed using a Monte Carlo microsimulation technique, consisting in simulating observations from known probability distributions depicted in the model. Eight-hundred-thousand simulations were performed to obtain the final estimates. All estimates were then subjected to Monte Carlo Probabilistic sensitivity analysis, to assess the impact of the variability of such estimates on the outcome distributions. RESULTS: The event rate (considered as progression of varices or bleeding or death) in Strategy 1 [24.09% (95%CI: 14.89%-33.29%)] was significantly lower than in Strategy 2 [60.00% (95%CI: 48.91%-71.08%)]. The mean cost (up to the first event) associated with Strategy 1 [823 £ (95%CI: 106 £-2036 £)] was not significantly different from that of Strategy 2 [799 £ (95%CI: 0 £-3498 £)]. The cost-effectiveness ratio with respect to this endpoint was equal to 50.26 £ (95%CI: -504.37 £-604.89 £) per event avoided over the four-year follow-up. When bleeding episodes/deaths in subjects whose varices had grown were included, the mean cost associated with Strategy 1 was 1028 £ (95%CI: 122 £-2581 £), while 1699 £ (95%CI: 171 £-4674 £) in Strategy 2. CONCLUSION: Beta-blocker therapy turn out to be more effective and less expensive than endoscopic surveillance for primary prophylaxis of bleeding in patients with cirrhosis and small varices.

Hepatic venous pressure gradient measurement in clinical hepatology.

Portal hypertension is key to the natural history of cirrhosis and the standard way to assess it is the hepatic venous pressure gradient. Hepatic venous pressure gradient is a strong predictor of variceal bleeding/survival and is the only suitable tool to assess the response of portal hypertension to medical treatment. The clinical applications, indications and timing for hepatic venous pressure gradient measurement, together with measurement principles and costs, are reviewed.