Psychiatric aspects of liver disease

Stress increases hepatic release of lipocalin 2 which contributes to anxiety-like behavior in mice

Chronic stress induces anxiety disorders via both neural pathways and circulating factors. Although many studies have elucidated the neural circuits involved in stress-coping behaviors, the origin and regulatory mechanism of peripheral cytokines in behavioural regulation under stress conditions are not fully understood. Here, we identified a serum cytokine, lipocalin 2 (LCN2), that was upregulated in participants with anxiety disorders. Using a mouse model of chronic restraint stress (CRS), circulating LCN2 was found to be related to stress-induced anxiety-like behaviour via modulation of neural activity in the medial prefrontal cortex (mPFC). These results suggest that stress increases hepatic LCN2 via a neural pathway, leading to disrupted cortical functions and behaviour.

A comprehensive gene-centric pleiotropic association analysis for 14 psychiatric disorders with GWAS summary statistics

BACKGROUND

Recent genome-wide association studies (GWASs) have revealed the polygenic nature of psychiatric disorders and discovered a few of single-nucleotide polymorphisms (SNPs) associated with multiple psychiatric disorders. However, the extent and pattern of pleiotropy among distinct psychiatric disorders remain not completely clear.

METHODS

We analyzed 14 psychiatric disorders using summary statistics available from the largest GWASs by far. We first applied the cross-trait linkage disequilibrium score regression (LDSC) to estimate genetic correlation between disorders. Then, we performed a gene-based pleiotropy analysis by first aggregating a set of SNP-level associations into a single gene-level association signal using MAGMA. From a methodological perspective, we viewed the identification of pleiotropic associations across the entire genome as a high-dimensional problem of composite null hypothesis testing and utilized a novel method called PLACO for pleiotropy mapping. We ultimately implemented functional analysis for identified pleiotropic genes and used Mendelian randomization for detecting causal association between these disorders.

RESULTS

We confirmed extensive genetic correlation among psychiatric disorders, based on which these disorders can be grouped into three diverse categories. We detected a large number of pleiotropic genes including 5884 associations and 2424 unique genes and found that differentially expressed pleiotropic genes were significantly enriched in pancreas, liver, heart, and brain, and that the biological process of these genes was remarkably enriched in regulating neurodevelopment, neurogenesis, and neuron differentiation, offering substantial evidence supporting the validity of identified pleiotropic loci. We further demonstrated that among all the identified pleiotropic genes there were 342 unique ones linked with 6353 drugs with drug-gene interaction which can be classified into distinct types including inhibitor, agonist, blocker, antagonist, and modulator. We also revealed causal associations among psychiatric disorders, indicating that genetic overlap and causality commonly drove the observed co-existence of these disorders.

CONCLUSIONS

Our study is among the first large-scale effort to characterize gene-level pleiotropy among a greatly expanded set of psychiatric disorders and provides important insight into shared genetic etiology underlying these disorders. The findings would inform psychiatric nosology, identify potential neurobiological mechanisms predisposing to specific clinical presentations, and pave the way to effective drug targets for clinical treatment.

Identifying pleiotropic genes for complex phenotypes with summary statistics from a perspective of composite null hypothesis testing

Pleiotropy has important implication on genetic connection among complex phenotypes and facilitates our understanding of disease etiology. Genome-wide association studies provide an unprecedented opportunity to detect pleiotropic associations; however, efficient pleiotropy test methods are still lacking. We here consider pleiotropy identification from a methodological perspective of high-dimensional composite null hypothesis and propose a powerful gene-based method called MAIUP. MAIUP is constructed based on the traditional intersection-union test with two sets of independent P-values as input and follows a novel idea that was originally proposed under the high-dimensional mediation analysis framework. The key improvement of MAIUP is that it takes the composite null nature of pleiotropy test into account by fitting a three-component mixture null distribution, which can ultimately generate well-calibrated P-values for effective control of family-wise error rate and false discover rate. Another attractive advantage of MAIUP is its ability to effectively address the issue of overlapping subjects commonly encountered in association studies. Simulation studies demonstrate that compared with other methods, only MAIUP can maintain correct type I error control and has higher power across a wide range of scenarios. We apply MAIUP to detect shared associated genes among 14 psychiatric disorders with summary statistics and discover many new pleiotropic genes that are otherwise not identified if failing to account for the issue of composite null hypothesis testing. Functional and enrichment analyses offer additional evidence supporting the validity of these identified pleiotropic genes associated with psychiatric disorders. Overall, MAIUP represents an efficient method for pleiotropy identification.

Proteomic Studies of Psychiatric Disorders

Many diseases result from programming effects in utero. This chapter describes recent advances in proteomic studies which have improved our understanding of the underlying pathophysiological pathways in the major psychiatric disorders, resulting in the development of potential novel biomarker tests. Such tests should be based on measurement of blood-based proteins given the ease of accessibility of this medium and the known connections between the periphery and the central nervous system. Most importantly, emerging biomarker tests should be developed on lab-on-a-chip and other handheld devices to enable point-of-care use. This should help to identify individuals with psychiatric disorders much sooner than ever before, which will allow more rapid treatment options for the best possible patient outcomes.

Proteomic Biomarker Identification in Cerebrospinal Fluid for Leptomeningeal Metastases with Neurological Complications

Leptomeningeal metastases (LM) from solid tumours, lymphoma and leukaemia are characterized by multifocal neurological deficits with a high mortality rate. Early diagnosis and initiation of treatment are essential to kerb neurological deterioration. However, this is not always possible as 25% of cerebrospinal fluid samples produce false-negative results at first cytological examination. The identification of biomarkers that allow stratification of individuals according to risk for developing LM would be a major benefit. Proteomic-based approaches are now in increasing use for this purpose, and these are reviewed in this chapter with a focus on cerebrospinal fluid (CSF) analyses. The construction of a CSF proteome disease database would also facilitate analysis of other neurological disorders.

Applications of blood-based protein biomarker strategies in the study of psychiatric disorders

Major psychiatric disorders such as schizophrenia, major depressive and bipolar disorders are severe, chronic and debilitating, and are associated with high disease burden and healthcare costs. Currently, diagnoses of these disorders rely on interview-based assessments of subjective self-reported symptoms. Early diagnosis is difficult, misdiagnosis is a frequent occurrence and there are no objective tests that aid in the prediction of individual responses to treatment. Consequently, validated biomarkers are urgently needed to help address these unmet clinical needs. Historically, psychiatric disorders are viewed as brain disorders and consequently only a few researchers have as yet evaluated systemic changes in psychiatric patients. However, promising research has begun to challenge this concept and there is an increasing awareness that disease-related changes can be traced in the peripheral system which may even be involved in the precipitation of disease onset and course. Converging evidence from molecular profiling analysis of blood serum/plasma have revealed robust molecular changes in psychiatric patients, suggesting that these disorders may be detectable in other systems of the body such as the circulating blood. In this review, we discuss the current clinical needs in psychiatry, highlight the importance of biomarkers in the field, and review a representative selection of biomarker studies to highlight opportunities for the implementation of personalized medicine approaches in the field of psychiatry. It is anticipated that the implementation of validated biomarker tests will not only improve the diagnosis and more effective treatment of psychiatric patients, but also improve prognosis and disease outcome.

Development of a High-Throughput Human HepG2 Dual Luciferase Assay for Detection of Metabolically Activated Hepatotoxicants and Genotoxicants

Hepatic toxicity remains a major concern for drug failure; therefore, a thorough examination of chemically induced liver toxicity is essential for a robust safety evaluation. Current hypotheses suggest that the metabolic activation of a drug to a reactive intermediate is an important process. In this article, we describe a new high-throughput GADD45β reporter assay developed for assessing potential liver toxicity. Most importantly, this assay utilizes a human cell line and incorporates metabolic activation and thus provides significant advantage over other comparable assays used to determine hepatotoxicity. Our assay has low compound requirement and relies upon 2 reporter genes cotransfected into the HepG2 cells. The gene encoding Renilla luciferase is fused to the CMV promoter and provides a control for cell numbers. The firefly luciferase gene is fused to the GADD45β promoter and used to report an increase in DNA damage. A dual luciferase assay is performed by measuring the firefly and Renilla luciferase activities in the same sample. Results are expressed as the ratio of the 2 luciferase activities; increases over the control are interpreted as evidence of stress responses. This mammalian dual luciferase reporter has been characterized with, and without, metabolic activation using positive and negative control agents. Our data demonstrate that this assay provides for an assessment of potential toxic metabolites, is adaptable to a high-throughput platform, and yields data that accurately and reproducibly detect hepatotoxicants.

Predictors of psychological morbidity in liver transplant assessment candidates: is alcohol abuse or dependence a factor?

Orthotopic liver transplantation candidates with depressive and other symptoms report poorer perceived quality of life when compared with nondepressed patients, and are also significantly more likely to die while awaiting transplantation. Alcohol abuse and dependence have been associated with increased levels of psychological co-morbidity. This article presents data about psychological morbidity from a prospective study of patients being assessed for liver transplantation in Birmingham, UK, and explores whether those with a diagnosis of alcohol abuse or dependence are at increased risk of psychological symptoms. Of 399 consecutive patients assessed for liver transplantation between July 2004 and July 2005, a sample of 155 was included in the study. Eighty-three (53.5%) patients were identified as having general psychological distress that merited referral for specialist assessment using the Symptom Checklist-90-Revised instrument. The alcohol-dependent group achieved the highest overall 'caseness' rates, with 72% (n = 26) compared with 52% (n = 12) of the alcohol-abuse group and 47% (n = 45) of those with no alcohol-related diagnosis. However, alcohol abuse or dependence was not the significant predictor of psychological symptoms in the final regression model. Higher rates of psychological distress were associated with greater severity of liver disease, being unemployed, and being a tobacco smoker. Possible reasons for these findings and potential future management strategies are discussed.

What are the nursing implications when using paliperidone prolonged release for people with schizophrenia

Paliperidone prolonged release (PR) is a new product licensed for the treatment of schizophrenia. It is the active metabolite of risperidone, a drug that has been successfully used in the treatment of schizophrenia and mood disorder. Paliperidone PR has a unique pharmacological delivery mechanism that may incur benefits for particular patients diagnosed with schizophrenia. Studies investigating paliperidone PR are reviewed along with implications for its use by nurse prescribers and those nurses who monitor the use of medication for people with psychosis.

Multidimensional assessment of neuro-psychiatric symptoms in patients with low-grade hepatic encephalopathy: A clinical rating scale

AIM: To evaluate the feasibility of a new clinical rating scale for a standardized assessment of cirrhosis-associated neuro-psychiatric symptoms.

METHODS: Forty patients with liver cirrhosis (LC, with or without low-grade hepatic encephalopathy) were invest-igated using a clinical neuro-psychiatric rating scale based on a comprehensive list of neurological, psychomotor, cognitive, affective, behavioral symptoms, and symptoms of disturbed bioregulation.

RESULTS: The analysis revealed that the majority of cirrhotic patients showed, besides characteristic neurological symptoms of hepatic encephalopathy, various psychomotor, affective and bioregulatory symptoms (disturbed sleep and sexual dysfunction). Patients were impaired in the following subscales: sleep and biorhythm disorder (75.0% of patients), Parkinsonoid symptoms (25.0%), affective symptoms (17.5%), and psychomotor retardation (12.5%). The increase of total neuro-psychiatric clinical score was significantly associated with the degree of hepatic enceph-alopathy.

CONCLUSION: This study suggests that a substantial number of patients with LC and low-grade hepatic encephalopathy manifest various clinical neuro-psychiatric symptoms. The use of a rating scale, which explores clinical dimensions of hepatic encephalopathy, would improve the management of patients with LC.

Predictors of psychiatric disorders in liver transplantation candidates: logistic regression models

This study has two goals. The first goal is to assess the prevalence of psychiatric disorders in orthotopic liver transplantation (OLT) candidates by means of standardized procedures because there has been little research concerning psychiatric problems of potential OLT candidates using standardized instruments. The second goal focuses on identifying predictors of these psychiatric disorders. One hundred sixty-five elective OLT candidates were assessed by our unit. Psychiatric diagnoses were based on the Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition. Patients also were assessed using the Hamilton Depression Rating Scale (HDRS) and the Spielberger Anxiety Index, State and Trait forms (STAI-X1 and STAI-X2). Severity of cirrhosis was assessed by applying Child-Pugh score criteria. Chi-squared and general linear model analysis of variance were used to test the univariate association between patient characteristics and both clinical psychiatric diagnoses and severity of psychiatric diseases. Variables with P less than.10 in univariate analyses were included in multiple regression models. Forty-three percent of patients presented at least one psychiatric diagnosis. Child-Pugh score and previous psychiatric diagnoses were independent significant predictors of depressive disorders. Severity of psychiatric symptoms measured by psychometric scales (HDRS, STAI-X1, and STAI-X2) was associated with Child-Pugh score in the multiple regression model. Our data suggest a high rate of psychiatric disorders, particularly adjustment disorders, in our sample of OLT candidates. Severity of liver disease emerges as the most important variable in predicting severity of psychiatric disorders in these patients.

Specific psychiatric morbidity in liver cirrhosis in a Nigerian general hospital setting

The purpose of this investigation was to explore the psychiatric complications of liver cirrhosis in a Nigerian general hospital setting. The mental state of 31 consecutive patients with liver cirrhosis seen in a gastroenterology unit, from July 1996 to August 1998, was assessed using the 30-item General Health Questionnaire (GHQ-30) and Present State Examination (PSE) and compared with those of 20 hypertensive patients and 20 apparently healthy controls. The socio-demographic characteristics of patients with liver cirrhosis who developed psychiatric complications were compared with those without such complications. The mental status of the cirrhosis patients in the present study was also compared with those of Chronic Obstructive Pulmonary Disease (COPD) and hemodialysis patients in earlier studies. About fifty-five percent of all the liver cirrhosis patients developed diagnosable psychiatric morbidity. This was significantly higher than that of the hypertensive patients (15%) or healthy controls (5%) (P=0.0001). The psychiatric conditions were depressive episode, generalized anxiety disorder, delirium and adjustment disorder. No socio-demographic parameter had a significant effect on the mental state of the patients with liver cirrhosis. The same proportion (55%) of hemodialysis and a lower proportion (30%) of COPD patients compared with cirrhosis patients had psychiatric morbidity. We found a high rate of psychiatric morbidity in the patients with liver cirrhosis compared with those of hypertension and normal subjects. None of the socio-demographic variables considered was found to be associated with psychiatric complications in the liver cirrhosis patients. Poor medical conditions seem to be associated with high levels of psychiatric morbidity.

Cytochrome oxidase activity of the suprachiasmatic nucleus and pineal gland in rats with portacaval shunt

Rhythmic behavioral and biochemical changes have been observed in both human and animal models with hepatic insufficiency. The basis of all these alterations is the principal endogenous pacemaker, the suprachiasmatic nucleus. The aim of this work, therefore, is to determine cytochrome c oxidase activity, a marker of neuronal activity and oxidative metabolism, in this nucleus in rats with portacaval shunt. In order to do this, this enzyme was histochemically marked and quantified by computer-assisted optical densitometry. Results show a reduced cytochrome oxidase activity in the suprachiasmatic nucleus in animals with portacaval shunts and, inversely, an increase in oxidative metabolism in the pineal gland, another circadian structure. However, the activity measured in a noncircadian brain structure, the hippocampus, which served as a control, showed no changes with surgery. Additionally, locomotor activity was assessed by actimeters and revealed a clearly reduced activity in animals with portacaval shunt. We conclude that the suprachiasmatic nucleus is possibly involved in the rhythmic changes associated with hepatic insufficiency.

Personality change as defensive responses of patients evaluated for liver transplant

Patients affected by endstage liver disease and awaiting liver transplant suffer very stressful conditions. The aim of this study was to evaluate the person ality and behavioral responses of a group of liver transplant candidates, 95 men (M age 50 yr.) and of a group of 18 normal men (M age 49 yr.). The 16 Personality Factor Questionnaire of Cattell, and the PSY Inventory for Behavioral Assessment were administered to assess personality and behavior. On the 16PF Questionnaire, patients had significantly different mean scores from normal subjects on Scale B- (low mental capacity), G (conformity), N (shrewdness), and Q1- (conservatism). They also showed a somewhat lower but not a statistically significant mean on Scale E (submissiveness). In addition, on the four second-order factors of the 16PF (Anxiety, Control, Pathemia, and Extraversion) patients had a significantly higher mean on Control. With respect to PSY Inventors factors, patients showed impairment in energy, sleep, sexual disturbances, and obsessive behaviors. It appears these patients with endstage liver disease, who were evaluated for liver transplant, showed psychological regressive functioning, i.e., high control and dependency on medical staff, submissiveness, which are interpretable as defensive responses to upcoming transplant.

The enzymatic formation of novel bile acid primary amides

Bifunctional peptidylglycine alpha-amidating monooxygenase (PAM) catalyzes the copper-, ascorbate-, and O(2)-dependent cleavage of C-terminal glycine-extended peptides and N-acylglycines to the corresponding amides and glyoxylate. The alpha-amidated peptides and the long-chain acylamides are hormones in humans and other mammals. Bile acid glycine conjugates are also substrates for PAM leading to the formation of bile acid amides. The (V(MAX)/K(m))(app) values for the bile acid glycine conjugates are comparable to other known PAM substrates. The highest (V(MAX)/K(m))(app) value, 3.1 +/- 0.12 x 10(5) M(-1) s(-1) for 3-sulfolithocholylglycine, is 6.7-fold higher than that for d-Tyr-Val-Gly, a representative peptide substrate. The time course for O(2) consumption and glyoxylate production indicates that bile acid glycine conjugate amidation is a two-step reaction. The bile acid glycine conjugate is first converted to an N-bile acyl-alpha-hydroxyglycine intermediate which is ultimately dealkylated to the bile acid amide and glyoxylate. The enzymatically produced bile acid amides and the carbinolamide intermediates were characterized by mass spectrometry and two-dimensional (1)H-(13)C heteronuclear multiple quantum coherence NMR.

Psychiatric aspects of portal-systemic encephalopathy

This paper focuses on psychiatric aspects of portal-systemic encephalopathy (PSE) due to chronic liver disease and/or portal-systemic shunting. Clinical syndromes of PSE are discussed from the point of view of biological psychiatry, but, psychological consequences of concomitant cognitive disorders are also addressed. Psychiatric symptoms of early PSE and sleep disorders in patients with chronic liver disease are of specific interest.

Psychological distress in patients with chronic, nonalcoholic, uncomplicated liver disease

To study whether the presence of significant disease in a major organ, possibly with minimal or no clinical symptoms, would be associated with psychological disturbance, 80 subjects suffering from chronic hepatitis or cirrhosis, of nonalcoholic etiology were interviewed. Of these, 64 had either minimal or no physical symptoms. Patients completed the Brief Symptom Inventory (BSI) and the Impact of Event Scale (IES), questionnaires, which measure symptoms of psychological distress. It was found that 50% of the liver subjects were defined as cases by the BSI criteria including 15% who were defined as severe cases. There were no gender differences. Forty-five percent of asymptomatic liver subjects were defined as cases. Psychological distress was significantly pronounced in subjects with less than 12 years of education. This study points to a significant incidence of psychological distress, even in clinically asymptomatic subjects, suffering from chronic, nonalcoholic, uncomplicated liver disease.

Transcending chronic liver disease: a qualitative study

This study explores and describes experiences of chronic liver disease from the patient's perspective. No qualitative research studies appear to have examined the experiences of these patients. In-depth focused interviews and grounded theory data collection and data analysis methods were used. A two-stage theoretical framework (becoming ill, and not living) of the experience of transcending chronic liver disease is presented. Sociological and psychological literature on common sense models of health and illness are briefly reviewed. Several suggestions for further research are made. The way in which this qualitative research study is leading to a quantitative and qualitative appraisal of the psychological adjustment in end-stage chronic liver disease patients is outlined.

Psychiatric and social outcome of liver transplantation

BACKGROUND

This study measures psychiatric morbidity, quality of life, and cognitive function after liver transplantation.

METHOD

We undertook a cross-sectional study, with a longitudinal subgroup. The setting was a tertiary referral centre for liver transplantation. The subjects were 30 post-liver-transplantation patients, including 11 also interviewed before the operation. The main outcome measures were the Clinical Interview Schedule (CIS), the General Health Questionnaire (GHQ), the Nottingham Health Profile (NHP), and the Mini-Mental State Examination (MMSE).

RESULTS

Of the patients, 8/30 were CIS cases, and 7/30 were GHQ cases. NHP scores were higher than a previous postal study indicated, with less impairment after than before transplant. MMSE scores were 24-30. Median GHQ was 7.0 before operation and 1.0 after operation (P = 0.03), with no significant change in CIS score.

CONCLUSION

Liver transplantation improves quality of life, but not to the level of the general population; post-transplantation patients have a prevalence of psychiatric morbidity comparable with that of general medical patients.

The psychiatric assessment of liver transplant patients with alcoholic liver disease: a review

Patients with severe alcoholic liver disease are receiving liver transplants in increasing numbers. Alcoholic liver transplant patients appear to have a good prognosis, yet alcoholic candidates may be rejected on psychiatric grounds alone. The role of the psychiatrist in the multidisciplinary assessment is discussed and the use of a number of predictors of outcome for alcoholic candidates considered. Studies examining these variables have many methodological limitations and it is therefore very difficult to draw any firm conclusions on their validity or reliability. Long-term prospective studies using appropriate measures of outcome should enable the liaison psychiatrist to provide more useful advice on the psychosocial outcome and treatment requirements of this growing group of patients.