Fatigue in primary biliary cirrhosis

New insights into the pathogenesis of primary biliary cholangitis asymptomatic stage

Primary biliary cholangitis (PBC) is a chronic cholestatic progressive liver disease and one of the most important progressive cholangiopathies in adults. Damage to cholangiocytes triggers the development of intrahepatic cholestasis, which progresses to cirrhosis in the terminal stage of the disease. Accumulating data indicate that damage to biliary epithelial cells [(BECs), cholangiocytes] is most likely associated with the intracellular accumulation of bile acids, which have potent detergent properties and damaging effects on cell membranes. The mechanisms underlying uncontrolled bile acid intake into BECs in PBC are associated with pH change in the bile duct lumen, which is controlled by the bicarbonate (HCO3-) buffer system "biliary HCO3- umbrella". The impaired production and entry of HCO3- from BECs into the bile duct lumen is due to epigenetic changes in expression of the X-linked microRNA 506. Based on the growing body of knowledge on the molecular mechanisms of cholangiocyte damage in patients with PBC, we propose a hypothesis explaining the pathogenesis of the first morphologic (ductulopenia), immunologic (antimitochondrial autoantibodies) and clinical (weakness, malaise, rapid fatigue) signs of the disease in the asymptomatic stage. This review focuses on the consideration of these mechanisms.

Importance of fatigue and its measurement in chronic liver disease

The mechanisms of fatigue in the group of people with non-alcoholic fatty liver disease and non-alcoholic steatohepatitis are protean. The liver is central in the pathogenesis of fatigue because it uniquely regulates much of the storage, release and production of substrate for energy generation. It is exquisitely sensitive to the feedback controlling the uptake and release of these energy generation substrates. Metabolic contributors to fatigue, beginning with the uptake of substrate from the gut, the passage through the portal system to hepatic storage and release of energy to target organs (muscle and brain) are central to understanding fatigue in patients with chronic liver disease. Inflammation either causing or resulting from chronic liver disease contributes to fatigue, although inflammation has not been demonstrated to be causal. It is this unique combination of factors, the nexus of metabolic abnormality and the inflammatory burden of non-alcoholic fatty liver disease and non-alcoholic steatohepatitis that creates pathways to different types of fatigue. Many use the terms central and peripheral fatigue. Central fatigue is characterized by a lack of self-motivation and can manifest both in physical and mental activities. Peripheral fatigue is classically manifested by neuromuscular dysfunction and muscle weakness. Therefore, the distinction is often seen as a difference between intention (central fatigue) versus ability (peripheral fatigue). New approaches to measuring fatigue include the use of objective measures as well as patient reported outcomes. These measures have improved the precision with which we are able to describe fatigue. The measures of fatigue severity and its impact on usual daily routines in this population have also been improved, and they are more generally accepted as reliable and sensitive. Several approaches to evaluating fatigue and developing endpoints for treatment have relied of biosignatures associated with fatigue. These have been used singly or in combination and include: physical performance measures, cognitive performance measures, mood/behavioral measures, brain imaging and serological measures. Treatment with non-pharmacological agents have been shown to be effective in symptom reduction, whereas pharmacological agents have not been shown effective.

Pharmacotherapies for fatigue in chronic liver disease (CLD): a systematic review and meta-analysis (protocol)

BACKGROUND

This is the protocol for a systematic review (and meta-analysis) of an intervention. The primary objective of this systematic review will be to assess the benefits and harms of pharmacological therapies (pharmacotherapies) for the management of fatigue in adults with CLD of any etiology. The effects of pharmacological therapies on fatigue in CLD will be compared against those of placebo, no intervention, or non-pharmacological interventions. Specifically, this review will examine whether pharmacological therapies improve CLD-associated fatigue, and if they do, what key elements are associated with their effectiveness. The results of this systematic review will assist clinicians, policy-makers, researchers, and people with CLD in decision-making on how best to manage fatigue and its associated symptoms.

METHODS

MEDLINE, SCOPUS, EMBASE, EU Clinical Trials Register, WHO International Clinical Trials Registry Platform, CENTRAL (The Cochrane Library), ClinicalTrials.gov, reference lists of articles and conference proceedings will be searched for relevant studies. No language or date restrictions will be applied. Eligible studies will include adults with CLD of any etiology. Included studies will be randomized controlled trials. From included studies, data on participant characteristics, study design, setting, research ethics compliance, and intervention outcomes will be extracted. Risk of bias in included studies will be assessed using the Cochrane Risk of Bias Tool. A random-effects meta-analysis will be conducted. If substantial or considerable levels of heterogeneity are detected, analysis will be limited to a narrative synthesis.

DISCUSSION

This systematic review will examine the effectiveness of pharmacological therapies on fatigue reduction in people with CLD. Such therapies may be more effective than non-pharmacological interventions in treating fatigue symptoms in CLD. Evidence derived from the findings of this study will guide future practice, policy, and research.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO, CRD42017076957.

Poststroke Fatigue: Emerging Evidence and Approaches to Management: A Scientific Statement for Healthcare Professionals From the American Heart Association

At least half of all stroke survivors experience fatigue; thus, it is a common cause of concern for patients, caregivers, and clinicians after stroke. This scientific statement provides an international perspective on the emerging evidence surrounding the incidence, prevalence, quality of life, and complex pathogenesis of poststroke fatigue. Evidence for pharmacological and nonpharmacological interventions for management are reviewed, as well as the effects of poststroke fatigue on both stroke survivors and caregivers.

A Randomized, Placebo-Controlled Clinical Trial of Efficacy and Safety: Modafinil in the Treatment of Fatigue in Patients With Primary Biliary Cirrhosis

BACKGROUND AND AIMS

Fatigue is a common symptom of primary biliary cirrhosis (PBC), and is associated with an impaired quality of life.

STUDY QUESTION

No studies have assessed the use of modafinil in fatigue related to PBC in a controlled manner.

STUDY DESIGN, MEASURES, AND OUTCOMES

A randomized, double-blind, placebo-controlled study was conducted to determine the safety and efficacy of modafinil for the treatment of fatigue in PBC. Forty patients were randomized to modafinil (n = 20) or placebo (n = 20) for 12 weeks. A verbal report of fatigue for at least 6 months was required for enrollment. Modafinil was administered at 100 mg by mouth once daily; a change by 50 mg every 2 weeks (maximum: 200 mg once daily) was allowed, depending on the subject's response to treatment. The primary outcome was defined as a ≥50% improvement in fatigue severity [quantified by the Fisk Fatigue Impact Scale (FFIS)] after 12 weeks of treatment, compared with baseline values.

RESULTS

Thirty-three PBC patients completed the study. After 12 weeks of therapy, only 5 patients had a ≥50% reduction in FFIS scores: 3 patients (17.6%) in the modafinil arm and 2 (12.5%) in the placebo arm (P = 1.00). Change in median FFIS score was not statistically different between patients in the 2 treatment groups (P = 0.36). Modafinil was associated with minimal adverse events (headaches, diarrhea, and rash).

CONCLUSIONS

In patients with PBC who have fatigue, treatment with modafinil for 12 weeks was safe and fairly well tolerated; however, it did not result in beneficial effects on fatigue compared with patients treated with placebo (CONSORT Table 1). ClinicalTrials.gov identifier NCT00943176.

Inflammation and the Silent Sequelae of Stroke

Depression and fatigue are common after stroke and negatively impact the quality of life of stroke survivors. The biological bases of these symptoms are unknown, but an abundance of data point to a role for inflammation. This review highlights evidence supporting the contribution of inflammation to poststroke depression and poststroke fatigue. Potential treatments for poststroke depression and poststroke fatigue are explored, with a special emphasis on those that modulate the immune response.

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.

Primary biliary cirrhosis: Clinical and laboratory criteria for its diagnosis

Primary biliary cirrhosis (PBC) is a chronic progressive cholestatic granulomatous, and destructive inflammatory lesion of small intralobular and septal bile ducts, which is likely to be caused by an autoimmune mechanism with a the presence of serum antimitochondrial antibodies and a potential tendency to progress to cirrhosis. Despite the fact that the etiology of this disease has been unknown so far, there has been a considerable body of scientific evidence that can reveal the clinical and laboratory signs of PBC and the individual components of its pathogenesis and elaborate diagnostic criteria for the disease and its symptomatic therapy. Deficiencies in autoimmune tolerance are critical factors for the initiation and perpetuation of the disease. The purpose of this review is to summarize the data available in the literature and the author’s findings on clinical and laboratory criteria for the diagnosis of PBC. This review describes the major clinical manifestations of the disease and the mechanisms of its development. It presents the immunological, biochemical, and morphological signs of PBC and their significance for its diagnosis. A great deal of novel scientific evidence for the problem of PBC has been accumulated. However, the inadequate efficiency of therapy for the disease lends impetus to the quest for its etiological factors and to further investigations of its pathogenetic mechanisms and, on this basis, to searches for new methods for its early diagnosis.

Recent advances in the development of farnesoid X receptor agonists

Farnesoid X receptors (FXRs) are nuclear hormone receptors expressed in high amounts in body tissues that participate in bilirubin metabolism including the liver, intestines, and kidneys. Bile acids (BAs) are the natural ligands of the FXRs. FXRs regulate the expression of the gene encoding for cholesterol 7 alpha-hydroxylase, which is the rate-limiting enzyme in BA synthesis. In addition, FXRs play a critical role in carbohydrate and lipid metabolism and regulation of insulin sensitivity. FXRs also modulate live growth and regeneration during liver injury. Preclinical studies have shown that FXR activation protects against cholestasis-induced liver injury. Moreover, FXR activation protects against fatty liver injury in animal models of nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH), and improved hyperlipidemia, glucose intolerance, and insulin sensitivity. Obeticholic acid (OCA), a 6α-ethyl derivative of the natural human BA chenodeoxycholic acid (CDCA) is the first-in-class selective FXR agonist that is ~100-fold more potent than CDCA. Preliminary human clinical trials have shown that OCA is safe and effective. In a phase II clinical trial, administration of OCA was well-tolerated, increased insulin sensitivity and reduced markers of liver inflammation and fibrosis in patients with type II diabetes mellitus and NAFLD. In two clinical trials of OCA in patients with primary biliary cirrhosis (PBC), a progressive cholestatic liver disease, OCA significantly reduced serum alkaline phosphatase (ALP) levels, an important disease marker that correlates well with clinical outcomes of patients with PBC. Together, these studies suggest that FXR agonists could potentially be used as therapeutic tools in patients suffering from nonalcoholic fatty and cholestatic liver diseases. Larger and Longer-term studies are currently ongoing.

Recent advances in the development of farnesoid X receptor agonists

Farnesoid X receptors (FXRs) are nuclear hormone receptors expressed in high amounts in body tissues that participate in bilirubin metabolism including the liver, intestines, and kidneys. Bile acids (BAs) are the natural ligands of the FXRs. FXRs regulate the expression of the gene encoding for cholesterol 7 alpha-hydroxylase, which is the rate-limiting enzyme in BA synthesis. In addition, FXRs play a critical role in carbohydrate and lipid metabolism and regulation of insulin sensitivity. FXRs also modulate live growth and regeneration during liver injury. Preclinical studies have shown that FXR activation protects against cholestasis-induced liver injury. Moreover, FXR activation protects against fatty liver injury in animal models of nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH), and improved hyperlipidemia, glucose intolerance, and insulin sensitivity. Obeticholic acid (OCA), a 6α-ethyl derivative of the natural human BA chenodeoxycholic acid (CDCA) is the first-in-class selective FXR agonist that is ~100-fold more potent than CDCA. Preliminary human clinical trials have shown that OCA is safe and effective. In a phase II clinical trial, administration of OCA was well-tolerated, increased insulin sensitivity and reduced markers of liver inflammation and fibrosis in patients with type II diabetes mellitus and NAFLD. In two clinical trials of OCA in patients with primary biliary cirrhosis (PBC), a progressive cholestatic liver disease, OCA significantly reduced serum alkaline phosphatase (ALP) levels, an important disease marker that correlates well with clinical outcomes of patients with PBC. Together, these studies suggest that FXR agonists could potentially be used as therapeutic tools in patients suffering from nonalcoholic fatty and cholestatic liver diseases. Larger and Longer-term studies are currently ongoing.

Synergistic effects between CA1 mu opioid and dopamine D1-like receptors in impaired passive avoidance performance induced by hepatic encephalopathy in mice

BACKGROUND AND AIM

Numerous investigations have indicated that hepatic encephalopathy (HE) alters the levels of various neurotransmitters. However, comprehensive data regarding the effects of CA1 opioidergic and dopaminergic (DAergic) systems on HE-induced amnesia are still lacking.

METHODS

Following intra-dorsal hippocampal (CA1) injection of mu opioid and dopamine D1- and D2-like receptors antagonists in male mice, one-trial step-down and hole-board paradigms were used to assess memory and exploratory behaviors, respectively.

RESULTS

Our data demonstrated that HE impairs memory 24 days after bile duct ligation (BDL). Furthermore, while the higher dose of DA D1-like receptor antagonist (SCH23390, 0.5 μg/mouse) induced amnesia and anxiogenic-like behaviors, mu receptor antagonist (naloxone: 0.0125, 0.025 and 0.05 μg/mouse) and DA D2-like receptor antagonist (sulpiride: 0.0625, 0.125 and 0.25 μg/mouse) by themselves, could not exert an effect on memory performance in passive avoidance task. On the other hand, pre-test injection of all drugs reversed the HE-induced amnesia 24 days after BDL, while having no effect on exploratory behaviors. Pre-test co-administration of the subthreshold dose SCH23390 (0.25 μg/mouse) and sulpiride (0.0625 μg/mouse) or naloxone (0.0125 μg/mouse) could likewise reverse the BDL-induced amnesia. However, when the subthreshold sulpiride plus naloxone were co-administered, BDL-induced amnesia was not blocked.

CONCLUSIONS

Memory performance is impaired 24 days post BDL and CA1 mu opioid and DA D1-like receptors antagonist synergistic effects are likely involved in this phenomenon.

Approach to a patient with elevated serum alkaline phosphatase

Cholestasis develops either from a defect in bile synthesis, impairment in bile secretion, or obstruction to bile flow, and is characterized by an elevated serum alkaline phosphatase and gamma-glutamyltransferase disproportionate to elevation of aminotransferase enzymes. Key elements to the diagnostic workup include visualization of the biliary tree by cholangiography and evaluation of liver histology. The hope is that recent advances in understanding the genetic factors and immune mechanisms involved in the pathogenesis of cholestasis will lead to newer therapeutic interventions in the treatment of these diseases.

Primary biliary cirrhosis

Primary biliary cirrhosis is a chronic autoimmune inflammatory disease of the liver with a striking female preponderance. It has an insidious onset and typically affects middle-aged women. The disease manifests gradually with symptoms of fatigue, pruritis, and increased alkaline phosphatase levels on laboratory evaluation. The hallmark of the disease is the circulating antimitochondrial antibody. Histology is characterized by inflammation of the bile ducts, destruction of cholangiocytes, and subsequent cholestasis, progressing to biliary cirrhosis. The standard treatment for primary biliary cirrhosis is ursodeoxycholic acid, which improves survival, but the disease can still lead to cirrhosis and liver failure over decades.

Critical flicker frequency fails to disclose brain dysfunction in patients with primary biliary cirrhosis

BACKGROUND

Recent studies suggest that stage-independent symptoms of primary biliary cirrhosis (PBC) such as chronic fatigue are a consequence of structural and functional abnormalities of the brain. Critical flicker frequency (CFF) is a psychophysiological modality analysing function of cerebral cortex.

AIM

To analyse the usefulness of CFF in detection of brain dysfunction in patients with PBC.

METHODS

Fifty-one (37 non-cirrhotic/14 cirrhotic) patients with PBC were included. Control group consisted of 31 matched healthy individuals. Fatigue and health-related quality of life (HRQoL) were assessed using Fatigue Impact Scale (FIS) and questionnaire PBC-40. CFF was analysed with HEPAtonorm Analyzer(®).

RESULTS

When compared to healthy controls all patients with PBC showed significantly impaired HRQoL in majority of PBC-40 domains and increased fatigue level in physical domain of FIS. No differences in HRQoL and PBC-40 domains were seen, when patients with and without cirrhosis where compared. CFF analysis showed no difference between healthy controls and patients with PBC. CFF did not correlate with PBC-40 and FIS domains.

CONCLUSION

CFF fails to determine brain dysfunction in non-encephalopatic patients with PBC, suggesting that functional efficiency of their cerebral cortex remains unaffected and other central mechanisms are responsible for chronic fatigue in these patients.

Primary biliary cirrhosis: a 2010 update

Primary biliary cirrhosis (PBC) is a chronic inflammatory autoimmune disease that mainly targets the cholangiocytes of the interlobular bile ducts in the liver. The condition primarily affects middle-aged women. Without treatment, PBC generally progresses to cirrhosis and eventually liver failure over a period of 10-20 years. PBC is a rare disease with prevalence of less than 1/2000. PBC is thought to result from a combination of multiple genetic factors and superimposed environmental triggers. The contribution of the genetic predisposition is evidenced by the familial clustering. Several risk factors, including exposure to infectious agents and chemical xenobiotics, have been suggested. Ursodeoxycholic acid (UDCA) is currently the only FDA-approved medical treatment for PBC. When administered at doses of 13-15 mg/kg/day, a majority of patients with PBC have a normal life expectancy without additional therapeutic measures. One out of three patients does not adequately respond to UDCA therapy and may need additional medical therapy and/or liver transplantation. This review summarises current knowledge on the epidemiology, ethiopathogenesis, clinical, and therapeutic aspects of PBC.

Fatigue measurements in patients with primary biliary cirrhosis and the risk of mortality during follow-up

BACKGROUND

Fatigue was recently suggested to predict an increased risk of mortality in a primary biliary cirrhosis (PBC) cohort during follow-up.

AIMS

To analyse the impact of fatigue on prognosis in PBC.

METHODS

Patients with PBC who had earlier completed the fatigue impact scale (FIS) were identified. Prognosis in terms of death and liver transplantation (Tx) was determined.

RESULTS

FIS values at baseline were analysed from 208 patients (192 females; median age 59 years (interquartile range 51-67), median follow-up of 5 years. Overall, 181 patients were alive at follow-up, 22 (12%) died and five (2.4%) underwent transplantation. FIS at baseline was 28 (12-47) and FIS at follow-up was 25 (8-64) (P<0.001; r=0.69). Among survivors, FIS at baseline was 27 (12-43), 36 (12-72) in those who died (P=0.059) and 99 (41-102) in those who underwent transplantation (P=0.0008). FIS at baseline was 44 (12-88) in patients with death and/or Tx vs. 27 (12-43) in survivors (P=0.003). Age [hazard ratio (HR) 1.1 (confidence interval (CI) 1.0-1.2)] and aspartate aminotransferase [HR 2.0 (CI 1.3-3.0)] were independently associated with decreased survival on multivariate analysis. FIS scores over 40 [HR 9.6 (CI 2.3-39.7)] and bilirubin [HR 4.8 (CI 2.8-8.2)] were independently associated with a poor outcome in patients who underwent Tx or had a liver-related death.

CONCLUSIONS

Fatigue seems to change little over time in PBC. Fatigue levels were higher at baseline in those who died or underwent Tx. High fatigue levels seem to be a predictor of risk of liver-related mortality and need for transplantation over time but not a predictor of non-liver-related mortality.

Microvascular optical assessment confirms the presence of peripheral autonomic dysfunction in primary biliary cirrhosis

BACKGROUND

Autonomic dysfunction (AD) is a significant problem in primary biliary cirrhosis (PBC) and is equally present in early disease stages. Currently, AD in PBC is considered to be central in origin. The aim of this study was to examine peripheral mechanisms in the pathogenesis of AD in PBC using novel microvascular optical assessments for this patient group.

METHODS

Twenty-four early stage PBC patients and 24 age-matched controls attended for two microvascular optical-based measurement techniques. Firstly, the regulation of microvascular blood volume to the periphery was assessed using multisite photoplethysmography (PPG) by examining the degree of correlation between the right and left sides of the body, with reduced correlation consistent with peripheral AD. Secondly, the peripheral vasomotor reflex response to standing was dynamically tested using laser Doppler flowmetry to quantify the degree of autonomic tone in peripheral vasoconstriction.

RESULTS

PBC patients had a significantly reduced right to left side blood volume multisite PPG correlation compared with controls when corrected for age, body mass index, heart rate and systolic blood pressure [impaired synchronization between pulse wave amplitude between right and left fingers and right and left ears (both P<0.05)]. The veno-arteriolar reflex on standing in PBC patients was significantly lower than for the controls, consistent with poorer autonomic tone for vasoconstriction in PBC (P<0.01).

CONCLUSIONS

This study provides evidence for the presence of peripheral autonomic nervous system involvement in PBC. Prospective studies are now warranted to determine the full clinical potential of microvascular optical assessment in PBC.