Primary biliary cirrhosis, hyperlipidemia, and atherosclerotic risk: a systematic review

Risk of Cardiovascular Events in Patients with Primary Biliary Cholangitis - Systematic Review

Background and Aims: Hypercholesterolemia is a common finding in patients with primary biliary cholangitis (PBC) and is a well-defined risk factor for cardiovascular disease. However, studies have been mixed on whether PBC patients do, in fact, have higher cardiovascular risk. The aim of this study is to review the current literature and provide an evidence-based assessment of cardiovascular risk in PBC patients. Methods: We performed a systematic literature search on PubMed regarding patients with PBC and cardiovascular events from the database inception to July 1, 2017. A total of 33 articles fulfilling our inclusion criteria were found. Results: The majority of the studies evaluated yielded no statistically significant difference in cardiovascular disease in the PBC population compared to the general public. However, some reports found a statistically significantly increase in coronary artery disease. Several studies have looked at the specific lipid profile of patients with PBC with hypocholesteremia. While these lipid abnormalities differ by stage of disease, there is evidence to suggest that the specific lipid profile in PBC may have lower atherogenicity than in patients with hypercholesterolemia without PBC. Studies looking at patients with PBC with other risk factors for cardiovascular disease, such as hypertension and metabolic syndrome, have consistently found a higher risk for cardiovascular disease in these patients. Statin treatment is effective in reducing lipid levels and possibly improving endothelial inflammation in patients with PBC with hypercholesterolemia. Conclusions: There is not enough evidence to suggest an increased risk of cardiovascular disease in patients with PBC with hypercholesterolemia, except for those individuals with concomitant features of metabolic syndrome. In patients with PBC with no additional cardiovascular risk factors, individual risk/benefit discussion on lipid-lowering treatment should be considered.

Extrahepatic Manifestations of Primary Biliary Cholangitis

Primary biliary cholangitis (PBC) is an autoimmune liver disease characterized by progressive destruction of the intrahepatic bile ducts, leading to cholestasis. PBC is known to have both hepatic and extrahepatic manifestations. Extrahepatic manifestations are seen in up to 73% of patients with PBC, with the most common being Sjogren’s syndrome, thyroid dysfunction and systemic sclerosis. It is thought that patients with PBC are at increased risk of developing these extrahepatic manifestations, almost all of which are autoimmune, because patients with autoimmune disease are at higher risk of developing another autoimmune condition. Due to the high prevalence of extrahepatic diseases in patients with PBC, it is important to complete a thorough medical history at the time of diagnosis. Prompt recognition of extrahepatic disease can lead to improved patient outcomes and quality of life. The following review summarizes the most common extrahepatic conditions associated with PBC.

A randomized trial of obeticholic acid monotherapy in patients with primary biliary cholangitis

Obeticholic acid (OCA), a potent farnesoid X receptor agonist, was studied as monotherapy in an international, randomized, double-blind, placebo-controlled phase 2 study in patients with primary biliary cholangitis who were then followed for up to 6 years. The goals of the study were to assess the benefit of OCA in the absence of ursodeoxycholic acid, which is relevant for patients who are intolerant of ursodeoxycholic acid and at higher risk of disease progression. Patients were randomized and dosed with placebo (n = 23), OCA 10 mg (n = 20), or OCA 50 mg (n = 16) given as monotherapy once daily for 3 months (1 randomized patient withdrew prior to dosing). The primary endpoint was the percent change in alkaline phosphatase from baseline to the end of the double-blind phase of the study. Secondary and exploratory endpoints included change from baseline to month 3/early termination in markers of cholestasis, hepatocellular injury, and farnesoid X receptor activation. Efficacy and safety continue to be monitored through an ongoing 6-year open-label extension (N = 28). Alkaline phosphatase was reduced in both OCA groups (median% [Q1, Q3], OCA 10 mg -53.9% [-62.5, -29.3], OCA 50 mg -37.2% [-54.8, -24.6]) compared to placebo (-0.8% [-6.4, 8.7]; P < 0.0001) at the end of the study, with similar reductions observed through 6 years of open-label extension treatment. OCA improved many secondary and exploratory endpoints (including γ-glutamyl transpeptidase, alanine aminotransferase, conjugated bilirubin, and immunoglobulin M). Pruritus was the most common adverse event; 15% (OCA 10 mg) and 38% (OCA 50 mg) discontinued due to pruritus.

CONCLUSION

OCA monotherapy significantly improved alkaline phosphatase and other biochemical markers predictive of improved long-term clinical outcomes. Pruritus increased dose-dependently with OCA treatment. Biochemical improvements were observed through 6 years of open-label extension treatment. (Hepatology 2018;67:1890-1902).

The Use of Statins in Patients With Chronic Liver Disease and Cirrhosis

PURPOSE OF REVIEW

Statins are drugs developed to treat hypercholesterolemia. Its use in patients with liver disease has been limited because one of its potential and most feared side effects is hepatotoxicity. However, there is robust evidence that supports the safety of statins in this population in the absence of severe liver dysfunction. In this review, we will summarize the efficacy and safety of statins in cirrhosis.

RECENT FINDINGS

Statins are effective in the treatment of dyslipidemia in patients with liver disease, because of their pleiotropic properties. These properties are independent of their effect on cholesterol levels, such as improving endothelial dysfunction or having antioxidant, antifibrotic, anti-inflammatory, antiproliferative, antiangiogenic, proapoptotic, or immunomodulation properties. Statins have been studied in other areas such as in treatment of portal hypertension, prevention of hepatocellular carcinoma, and/or protection against ischemia/reperfusion injury. Approved indications for statins in patients with cirrhosis are those of the general population, including dyslipidemia and increased cardiovascular risk. Compensated cirrhosis is not a contraindication. In patients with decompensated cirrhosis, statins should be prescribed with extreme caution at low doses, and with frequent monitoring of creatinine phosphokinase levels in order to detect adverse events in a timely fashion.

Abnormalities of Lipoprotein Levels in Liver Cirrhosis: Clinical Relevance

Progressive lipoprotein impairment occurs in liver cirrhosis and is associated with increased morbidity and mortality. The present review aims to summarize the current evidence regarding the prognostic value of lipoprotein abnormalities in liver cirrhosis and to address the need of a better prognostic stratification of patients, including lipoprotein profile assessment. Low levels of lipoproteins are usual in cirrhosis. Much evidence supports the prognostic role of hypolipidemia in cirrhotic patients. In particular, hypocholesterolemia represents an independent predictor of survival in cirrhosis. In cirrhotic patients, lipoprotein impairment is associated with several complications: infections, malnutrition, adrenal function, and spur cell anemia. Alterations of liver function are associated with modifications of circulating lipids. Decreased levels of lipoproteins significantly impact the survival of cirrhotic patients and play an important role in the pathogenesis of some cirrhosis-related complications.

An Update on the Treatment and Follow-up of Patients with Primary Biliary Cholangitis

Primary biliary cholangitis (PBC) is an autoimmune liver disease characterized by chronic granulomatous lymphocytic cholangitis of the small bile ducts. PBC was a leading indication for liver transplant in the United States; with early diagnosis and treatment, the majority of patients with PBC have a normal life expectancy. Pathogenesis involves inflammatory damage of bile duct epithelium secondary to innate and adaptive immune responses, and toxicity from accumulated bile acids. Cholestasis and disease progression can lead to cirrhosis. Extrahepatic complications include dyslipidemia, metabolic bone disease, and fat-soluble vitamin deficiency. Ursodeoxycholic acid is a well-established therapy. Novel targeted therapeutics are being developed.

Clinical Course and Genetic Susceptibility of Primary Biliary Cirrhosis: Analysis of a Prospective Cohort

BACKGROUND

Natural history of primary biliary cirrhosis (PBC) is partially characterized in patients from the Mediterranean area whose genetic background differs from that of Northern Europeans.

OBJECTIVES

We aimed to describe genetic susceptibility and clinical course of PBC in patients from Southern Italy.

METHODS

Socio-demographic, clinical, biochemical and histological data at diagnosis as well as disease progression of 81 PBC consecutive patients were collected. All subjects were treated with Ursodeoxycholic acid at a dose of 15 mg/kg. HLA class II DRB1 alleles were compared with those of 237 healthy control subjects. IL28B genotyping for IL28B rs12979860 C/T and rs80899917 G/T was performed in a sub-group of patients.

RESULTS

HLA-DRB1*07 (RR 5.3, P = 0.0008) and HLA-DRB1*08 (RR n.c. P = 0.0005) were significantly associated with the risk of PBC development. Patients younger than 45 years had significantly higher alanine aminotransferase (P = 0.038) and alkaline phosphatase levels (P = 0.047) than older cases. In comparison to non-CC rs12979860, patients with CC rs12979860 genotype showed an early histological stage at onset (93.8% vs. 62.5%, P = 0.03). After a mean follow-up of 61 months, three patients died, one underwent liver transplantation and sixteen (21.9%) had progression of the disease. At multivariate analysis, extrahepatic autoimmune disease (P = 0.04), pruritus (P = 0.008) and advanced histological stage (P < 0.0001) were independent risk factors for disease progression.

CONCLUSIONS

HLA-DRB1*07 and HLA-DRB1*08 alleles increase susceptibility to disease development. At onset, higher biochemical activity was observed in younger patients, whereas rs12979860 CC genotype was associated with milder histological stage. Pruritus and coexistence of extrahepatic autoimmune diseases were significantly associated with poorer prognosis.

Lipoprotein-X disease in the setting of severe cholestatic hepatobiliary autoimmune disease

Severe cholestatic disease and hyperlipidemia are both commonly encountered by medical professionals. This article reviews the current pathophysiological model of lipoprotein-X syndrome related to 3 cases from 2 academic medical centers in the United States.

Obeticholic acid for the treatment of primary biliary cholangitis

INTRODUCTION

Primary biliary cholangitis (PBC) is an autoimmune disease of the liver characterized by destruction and inflammation of the intrahepatic bile ducts. The disease affects mainly women. The disease is often discovered through abnormal alkaline phosphatase (ALP) activity, and is confirmed when anti-mitochondrial antibodies (AMA) are present. The etiology of PBC is poorly understood. Cigarette smoking, immune dysregulation, nail polish, urinary tract infections, and low socioeconomic status have been implicated but none have been confirmed. Genome wide association studies (GWAS) have disclosed strong associations between certain human leukocyte antigen (HLA) alleles and PBC. PBC can progress to cirrhosis and end-stage liver disease. Hepatocellular carcinoma (HCC) develops in up to 3.5% of PBC patients. Ursodeoxycholic acid (UDCA) is the only medication approved for the treatment of PBC. The use of UDCA in PBC delays histological progression and extends the transplant-free survival. 40% of PBC patients do not respond adequately to UDCA, and these patients are at high risk for serious complications. Therefore, there is a critical need for more effective therapies for this problematic disease. Multiple other agents have either been or are currently being studied as therapeutic options in UDCA non-responder PBC patients. Six-ethyl chenodeoxycholic acid (6-ECDCA), a potent farnesoid X receptor (FXR) agonist, has shown anti-cholestatic activity in rodent models of cholestasis. Obeticholic acid (OCA, 6-ECDCA, or INT-747), a first-in-class FXR agonist, has been examined in PBC patients with inadequate response to UDCA, and shown promising results. Particularly, initial clinical trials have demonstrated that the use of OCA (in addition to UDCA) in PBC patients with inadequate response to UDCA led to significant reduction of serum alkaline phosphatase (ALP, an important prognostic marker in PBC). More recently, the results of a randomized clinical trial of OCA monotherapy in PBC reported significant reduction of ALP in the treatment group compared to placebo.

AREAS COVERED

This review covers the preclinical and clinical studies of OCA in PBC. In addition, other alternative therapies that are currently being examined in PBC patients will also be discussed in this review. A literature search was carried out using the PubMed database.

EXPERT OPINION

If approved by the U.S. FDA, OCA will likely be an important alternative add-on therapy in PBC patients who have inadequate response to UDCA.

Cholesterol metabolism in cholestatic liver disease and liver transplantation: From molecular mechanisms to clinical implications

The aim of this review is to enlighten the critical roles that the liver plays in cholesterol metabolism. Liver transplantation can serve as gene therapy or a source of gene transmission in certain conditions that affect cholesterol metabolism, such as low-density-lipoprotein (LDL) receptor gene mutations that are associated with familial hypercholesterolemia. On the other hand, cholestatic liver disease often alters cholesterol metabolism. Cholestasis can lead to formation of lipoprotein X (Lp-X), which is frequently mistaken for LDL on routine clinical tests. In contrast to LDL, Lp-X is non-atherogenic, and failure to differentiate between the two can interfere with cardiovascular risk assessment, potentially leading to prescription of futile lipid-lowering therapy. Statins do not effectively lower Lp-X levels, and cholestasis may lead to accumulation of toxic levels of statins. Moreover, severe cholestasis results in poor micellar formation, which reduces cholesterol absorption, potentially impairing the cholesterol-lowering effect of ezetimibe. Apolipoprotein B-100 measurement can help distinguish between atherogenic and non-atherogenic hypercholesterolemia. Furthermore, routine serum cholesterol measurements alone cannot reflect cholesterol absorption and synthesis. Measurements of serum non-cholesterol sterol biomarkers - such as cholesterol precursor sterols, plant sterols, and cholestanol - may help with the comprehensive assessment of cholesterol metabolism. An adequate cholesterol supply is essential for liver-regenerative capacity. Low preoperative and perioperative serum cholesterol levels seem to predict mortality in liver cirrhosis and after liver transplantation. Thus, accurate lipid profile evaluation is highly important in liver disease and after liver transplantation.

Severe hypercholesterolemia and liver disease in a 3-year old

Lipoprotein-X, which is composed of phospholipids and non-esterified cholesterol, is an abnormal lipoprotein with a density range similar to LDL-C. The two most common ways which lipoprotein-X accumulates is from reflux of bile salts into plasma or deficiency in lecithin cholesterol acyltransferase. This is a case of severe hypercholesterolemia and liver disease in a 3- year old male that presented with pruritus, pale stool, scleral ictus, and abdominal distention. He was diagnosed with primary sclerosing cholangitis which was confirmed by liver biopsy. Our patient was treated with steroids and immunomodulator therapy which was associated with significant reduction in cholestasis and LDL-C levels. Lipoprotein-X has several properties that make it anti-atherogenic, which raises the question if treatment for hypercholesterolemia should be initiated.

Statins and the Liver

Lipid lowering, particularly with 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors ("statins"), reduces the risk of cardiovascular disease. Patients with chronic liver disease present challenges to the use of lipid medications. In the case of most liver disorders, the concern has been one of safety. There is evidence that most lipid-lowering medications can be used safely in many situations, although large outcomes trials are lacking. This review examines lipid physiology and cardiovascular risk in specific liver diseases and reviews the evidence for lipid lowering and the use of statins in chronic liver disease.

Risk of cerebrovascular accident in patients with primary biliary cirrhosis: a systematic review and meta-analysis

OBJECTIVE

Dyslipidemia is common among patients with primary biliary cirrhosis (PBC) and might increase the risk of cerebrovascular accident (CVA). However, data from epidemiologic studies remain inconclusive. This study aims to further investigate this association.

MATERIALS AND METHODS

We carried out a systematic review and meta-analysis of observational studies that compared the risk of CVA in patients with PBC versus controls. Pooled risk ratios and 95% confidence intervals were combined using a random-effect, generic inverse variance method of DerSimonian and Laird.

RESULTS

Four studies with 2309 patients with PBC were identified and included in our data analysis. The pooled risk ratio of CVA in patients with PBC was 1.11 (95% confidence interval, 0.81-1.51). The statistical heterogeneity was insignificant, with an I of 14%.

CONCLUSION

A significantly increased risk of CVA among patients with PBC was not observed in this study.

Obeticholic acid for the treatment of primary biliary cirrhosis

Primary biliary cirrhosis (PBC) is characterized by progressive nonsuppurative destruction of small bile ducts, resulting in intrahepatic cholestasis, fibrosis and ultimately end-stage liver disease. Timely intervention with ursodeoxycholic acid is associated with excellent survival, although approximately one-third of all patients fail to achieve biochemical response, signifying a critical need for additional therapeutic strategies. Obeticholic acid (OCA) is a potent ligand of the nuclear hormone receptor farnesoid X receptor (FXR). Activation of FXR inhibits bile acid synthesis and protects against toxic accumulation in models of cholestasis and facilitates hepatic regeneration in preclinical studies. Data from recent Phase II and III controlled trials suggest a therapeutic impact of OCA in PBC biochemical nonresponders, as evidenced by change in proven laboratory surrogates of long-term outcome. Dose-dependent pruritus is a common adverse effect, but may be overcome through dose-titration. Longer term studies are needed with focus on safety and long-term clinical efficacy.

Coronary artery disease in primary biliary cirrhosis: A systematic review and meta-analysis of observational studies

AIM

To investigate the association between primary biliary cirrhosis (PBC) and risk of coronary artery disease (CAD).

METHODS

We conducted a systematic review and meta-analysis of published observational studies that reported relative risks, odd ratios, hazard ratios or standardized incidence ratios with 95% confidence intervals (CI) comparing CAD risk in patients with PBC versus non-PBC controls. Pooled risk ratios and 95% confidence intervals were combined using a random-effect model and generic inverse variance of DerSimonian and Laird methods.

RESULT

Four studies with 3362 patients with PBC were identified and included in our data analysis. The pooled risk ratio of CAD in patients with PBC was 1.57 (95% CI, 1.21-2.06). The statistical heterogeneity was low with an I(2) of 38%.

CONCLUSION

Our study demonstrated a statistically significant increased risk of CAD among patients with PBC.

Primary biliary cirrhosis

Primary biliary cirrhosis is a chronic cholestatic liver disease characterised by destruction of small intrahepatic bile ducts, leading to fibrosis and potential cirrhosis through resulting complications. The serological hallmark of primary biliary cirrhosis is the antimitochondrial antibody, a highly disease-specific antibody identified in about 95% of patients with primary biliary cirrhosis. These patients usually have fatigue and pruritus, both of which occur independently of disease severity. The typical course of primary biliary cirrhosis has changed substantially with the introduöction of ursodeoxycholic acid (UDCA). Several randomised placebo-controlled studies have shown that UDCA improves transplant-free survival in primary biliary cirrhosis. However, about 40% of patients do not have a biochemical response to UDCA and would benefit from new therapies. Liver transplantation is a life-saving surgery with excellent outcomes for those with decompensated cirrhosis. Meanwhile, research on nuclear receptor hormones has led to the development of exciting new potential treatments. This Seminar will review the current understanding of the epidemiology, pathogenesis, and natural history of primary biliary cirrhosis, discuss management of the disease and its sequelae, and introduce research on new therapeutic options.

Efficacy of obeticholic acid in patients with primary biliary cirrhosis and inadequate response to ursodeoxycholic acid

BACKGROUND & AIMS

We evaluated the efficacy and safety of obeticholic acid (OCA, α-ethylchenodeoxycholic acid) in a randomized controlled trial of patients with primary biliary cirrhosis who had an inadequate response to ursodeoxycholic acid therapy.

METHODS

We performed a double-blind study of 165 patients with primary biliary cirrhosis (95% women) and levels of alkaline phosphatase (ALP) 1.5- to 10-fold the upper limit of normal. Patients were randomly assigned to groups given 10 mg, 25 mg, or 50 mg doses of OCA or placebo, once daily for 3 months. Patients maintained their existing dose of ursodeoxycholic acid throughout the study. The primary outcome was change in level of ALP from baseline (day 0) until the end of the study (day 85 or early termination). We also performed an open-label extension of the trial in which 78 patients were enrolled and 61 completed the first year.

RESULTS

OCA was superior to placebo in achieving the primary end point. Subjects given OCA had statistically significant relative reductions in mean ALP from baseline to the end of the study (P < .0001 all OCA groups vs placebo). Levels of ALP decreased 21%-25% on average from baseline in the OCA groups and 3% in the placebo group. Sixty-nine percent (68 of 99) of patients given OCA had at least a 20% reduction in ALP compared with 8% (3 of 37) of patients given placebo (P < .0003). Among secondary end points, levels of γ-glutamyl transpeptidase decreased 48%-63%, on average, among subjects given OCA, vs a 7% decrease in the group given placebo; levels of alanine aminotransferase decreased 21%-35% on average among subjects given OCA vs none of the patients given placebo. Pruritus was the principal adverse event; incidence values in the OCA 10 mg, 25 mg, and 50 mg groups were 47% (not significantly different), 87% (P < .0003), and 80% (P < .006), respectively, vs 50% in the placebo group. In the extension study, levels of ALP continued to decrease to a mean level of 202 ± 11 U/L after 12 months vs 285 ± 15 U/L at baseline.

CONCLUSIONS

Daily doses of OCA, ranging from 10 to 50 mg, significantly reduced levels of ALP, γ-glutamyl transpeptidase, and alanine aminotransferase, compared with placebo, in patients with primary biliary cirrhosis who had inadequate responses to ursodeoxycholic acid. The incidence and severity of pruritus were lowest among patients who received 10 mg/d OCA. Biochemical responses to OCA were maintained in a 12-month open-label extension trial. ClinicalTrials.gov ID: NCT00550862.

Negative feedback loop of cholesterol regulation is impaired in the livers of patients with Alagille syndrome

AIM

To characterize cholesterol regulation in the liver of patients with Alagille syndrome (AGS).

METHODS

Serum total cholesterol (TC) and total bile acid (TBA) levels were measured in 23 AGS patients. The expressions of genes involved in cholesterol regulation, including low-density lipoprotein receptor (LDLR), scavenger receptor class B type I (SR-BI), 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGCR), cholesterol 7α-hydroxylase (CYP7A1), ATP-binding cassette transporter (ABC) A1, and ABCG1/5/8, were measured in liver tissues from five of these patients. Expression of regulators for these genes, including farnesoid X receptor/small heterodimer partner (SHP), liver X receptor α (LXRα) and mature Sterol regulatory element-binding protein 2 (SREBP2) was measured. The expression of mature SREBP2 protein was also examined.

RESULTS

Serum TC and TBA levels were correlated in the AGS patients. Liver cholesterol was also increased compared with controls, and correlated with bile acid contents. LDLR, SR-BI, HMGCR, and ABCGs mRNA expression were upregulated, while CYP7A1 mRNA expression was downregulated in AGS livers. SHP and LXRα mRNA expression was also increased, but maturation of SREBP2 was not suppressed in the patients.

CONCLUSIONS

The major upregulators of liver cholesterol might be increased in AGS patients, indicating an impaired negative feedback mechanism and accelerated liver cholesterol accumulation.

Primary Biliary Cirrhosis and Primary Sclerosing Cholangitis: a Review Featuring a Women's Health Perspective

Primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC) are two major types of chronic cholestatic liver disease. Each disorder has distinguishing features and variable progression, but both may ultimately result in cirrhosis and hepatic failure. The following offers a review of PBC and PSC, beginning with a general overview of disease etiology, pathogenesis, diagnosis, clinical features, natural course, and treatment. In addition to commonly associated manifestations of fatigue, pruritus, and fat-soluble vitamin deficiency, select disease-related topics pertaining to women's health are discussed including metabolic bone disease, hyperlipidemia and cardiovascular risk, and pregnancy-related issues influencing maternal disease course and birth outcomes. This comprehensive review of PBC and PSC highlights some unique clinical considerations in the care of female patients with cholestatic liver disease.

Lipid lowering in liver and chronic kidney disease

Lipid lowering, particularly with HMG CoA reductase inhibitors ("statins"), reduces the risk of cardiovascular disease. Patients with chronic liver and kidney disease present challenges to the use of lipid medications. In the case of most liver disorders, the concern has been one of safety. There is evidence that most lipid-lowering medications can be used safely in many situations, although large outcomes trials are not available. In contrast, in chronic kidney disease, dosing of lipid medications may require substantial modification depending on creatinine clearance. There are significant alterations in lipid metabolism in chronic kidney disease with concomitant increases in cardiovascular risk. Some data are available on cardiovascular outcomes with dyslipidemia treatment in renal patients. This review will examine lipid physiology and cardiovascular risk in specific liver and kidney diseases and review the evidence for lipid lowering and the use of statin and non-statin therapies in chronic liver and kidney disease.

[Effect of biliary obstruction on lipoprotein(a) concentration]

OBJECTIVES

This study was appointed to determine the correlation between the concentration of lipoprotein(a) [Lp(a)], apolipoproteins and lipids with biochemical parameters of liver function in a group of patients with reversible cholestasis. We have also determined the concentration of these parameters once solved the biliary obstruction process.

MATERIAL AND METHODS

Eighteen adults over 17 years with extrahepatic cholestasis were included in the study on a prospective basis, and we determined in them biochemical liver function parameters and lipoprotein metabolism parameters, particularly Lp(a) before and after unblocking.

RESULTS

The concentration of Lp(a) prior to desobstruction was inverse and statistically significantly correlated with the concentration of gamma glutamyl transpeptidase (correlation coefficient [r] = -0.757, P = .018). The concentration of Lp(a) (median = 2.66 mg/dL, interquartile range = 5,62) showed a statistically significant increase (median = 9.72 mg/dL, interquartile range = 28.76, P < .001), once the unblocking was performed. Concentrations of total cholesterol and triglycerides had a statistically significant decrease, and HDL cholesterol and apolipoprotein A-1 showed a statistically significant increase once the unblocking was carried out.

CONCLUSIONS

The concentration of Lp(a) is decreased during cholestasis, although there is a significant simultaneous hypercholesterolemia. Cholestasis has a causal role in lowering Lp(a), because the unblocking of bile duct recovers Lp(a) concentration. Our study supports the concept that bile acids exert a controlling effect on the synthesis of Lp(a) and open a mechanism for the treatment of hyper Lp(a).

Randomized controlled trial assessing the effect of simvastatin in primary biliary cirrhosis

BACKGROUND

This study evaluated the effect of statins in Primary biliary cirrhosis (PBC) on endothelial function, anti-oxidant status and vascular compliance.

METHODS

Primary biliary cirrhosis patients with hypercholesterolaemia were randomized to receive 20 mg simvastatin or placebo in a single blind, randomized controlled trial. Body mass index, blood pressure, glucose, liver function, lipid profile, immunoglobulin levels, serological markers of endothelial function and anti-oxidant status were measured as well as vascular compliance, calculated from pulse wave analysis and velocity, at recruitment and again at 3, 6, 9 and 12 months.

RESULTS

Twenty-one PBC patients (F = 20, mean age = 55) were randomized to simvastatin 20 mg (n = 11) or matched placebo (n = 10). At completion of the trial, serum cholesterol levels in the simvastatin group were significantly lower compared with the placebo group (4.91 mmol/L vs. 6.15 mmol/L, P = 0.01). Low-density lipoprotein (LDL) levels after 12 months were also significantly lower in the simvastatin group (2.33 mmol/L vs. 3.53 mmol/L, P = 0.01). After 12 months of treatment, lipid hydroperoxides were lower (0.49 μmol/L vs. 0.59 μmol/L, P = 0.10) while vitamin C levels were higher (80.54 μmol/L vs. 77.40 μmol/L, P = 0.95) in the simvastatin group. Pulse wave velocity remained similar between treatment groups at 12 months (8.45 m/s vs. 8.80 m/s, P = 0.66). Only one patient discontinued medication owing to side effects. No deterioration in liver transaminases was noted in the simvastatin group.

CONCLUSIONS

Statin therapy in patients with PBC appears safe and effective towards overall reductions in total cholesterol and LDL levels. Our initial study suggests that simvastatin may also confer advantageous effects on endothelial function and antioxidant status.

Liver disease and malnutrition

Patients with hepatic disorders are exceptionally vulnerable to developing malnutrition because of the key role played by the liver in regulating the nutritional state and the energy balance. Moreover, the presence of chronic liver disorders could reduce the appetite and thus influence the nutrient intake. Poor nutritional status has been shown in various patient groups with hepatic disorders, and particularly in patients with alcoholic cirrhosis who are at high nutritional risk. It is well established that malnourished patients with liver diseases generally have a higher risk of developing adverse clinical outcomes and increased healthcare costs. Nutrition screening with the Subjective Global Assessment and anthropometric measurements are an important first step in the early identification of malnutrition and initiates the whole nutrition care process. It is therefore important for appropriate nutrition policies and protocols to be implemented so that all patients with chronic liver diseases are monitored closely from a nutritional standpoint. Early and evidence-based nutritional interventions are eagerly needed to minimize the nutritional decline associated with chronic liver disorders and ultimately improve the prognosis of such patients. This review includes a comprehensive analysis of methods to identify malnutrition in patients with chronic liver diseases as well as the extent and impact of the malnutrition problem in selected patient populations.

Anticholestatic effects of bezafibrate in patients with primary biliary cirrhosis treated with ursodeoxycholic acid

Bezafibrate is a widely used hypolipidemic agent and is known as a ligand of the peroxisome proliferator-activated receptors (PPARs). Recently this agent has come to be recognized as a potential anticholestatic medicine for the treatment of primary biliary cirrhosis (PBC) that does not respond sufficiently to ursodeoxycholic acid (UDCA) monotherapy. The aim of this study was to explore the anticholestatic mechanisms of bezafibrate by analyzing serum lipid biomarkers in PBC patients and by cell-based enzymatic and gene expression assays. Nineteen patients with early-stage PBC and an incomplete biochemical response to UDCA (600 mg/day) monotherapy were treated with the same dose of UDCA plus bezafibrate (400 mg/day) for 3 months. In addition to the significant improvement of serum biliary enzymes, immunoglobulin M (IgM), cholesterol, and triglyceride concentrations in patients treated with bezafibrate, reduction of 7α-hydroxy-4-cholesten-3-one (C4), a marker of bile acid synthesis, and increase of 4β-hydroxycholesterol, a marker of CYP3A4/5 activity, were observed. In vitro experiments using human hepatoma cell lines demonstrated that bezafibrate controlled the target genes of PPARα, as well as those of the pregnane X receptor (PXR); down-regulating CYP7A1, CYP27A1, and sinusoidal Na(+) /taurocholate cotransporting polypeptide (NTCP), and up-regulating CYP3A4, canalicular multidrug resistance protein 3 (MDR3), MDR1, and multidrug resistance-associated protein 2 (MRP2).

CONCLUSION

Bezafibrate is a dual PPARs/PXR agonist with potent anticholestatic efficacy in early-stage PBC patients with an incomplete biochemical response to UDCA monotherapy.

Farnesoid X receptor activation increases cholesteryl ester transfer protein expression in humans and transgenic mice

Cholesteryl ester transfer protein (CETP) activity results in a proatherogenic lipoprotein profile. In cholestatic conditions, farnesoid X receptor (FXR) signaling by bile acids (BA) is activated and plasma HDL cholesterol (HDL-C) levels are low. This study tested the hypothesis that FXR-mediated induction of CETP contributes to this phenotype. Patients with cholestasis and high plasma BA had lower HDL-C levels and higher plasma CETP activity and mass compared with matched controls with low plasma BA (each P < 0.01). BA feeding in APOE3*Leiden transgenic mice expressing the human CETP transgene controlled by its endogenous promoter increased cholesterol within apoB-containing lipoproteins and decreased HDL-C (each P < 0.01), while hepatic CETP mRNA expression and plasma CETP activity and mass increased (each P < 0.01). In vitro studies confirmed that FXR agonists substantially augmented CETP mRNA expression in hepatocytes and macrophages dependent on functional FXR expression (each P < 0.001). These transcriptional effects are likely mediated by an ER8 FXR response element (FXRE) in the first intron. In conclusion, using a translational approach, this study identifies CETP as novel FXR target gene. By increasing CETP expression, FXR activation leads to a proatherogenic lipoprotein profile. These results have clinical relevance, especially when considering FXR agonists as emerging treatment strategy for metabolic disease and atherosclerosis.

Assessment of metabolic syndrome in patients with primary biliary cirrhosis

BACKGROUND

Primary biliary cirrhosis (PBC) is a chronic, progressive liver disease with elevated serum lipids. It remains unclear if hyperlipidemia increases the risk for atherosclerosis in PBC patients. Metabolic syndrome (MS) promotes the development of atherosclerotic cardiovascular disease due to abdominal obesity and insulin resistance.

AIMS

The aim of this study was to assess incidence and parameters of MS, as well as subcutaneous and visceral fat using noninvasive ultrasonographic measurement in patients with PBC in our population.

METHODS

We included 55 patients with PBC and 44 age- and sex-matched healthy controls (CG-control group). Anthropometric measurements (weight, height, and waist circumference), age, sex, and body mass index were recorded for patients and controls. Laboratory tests for assessing MS and liver function tests were analyzed. We used ultrasonography to determine subcutaneous and visceral fat diameter and area (SF, VF and SA, VA, respectively), as well as perirenal fat diameter (PF).

RESULTS

Patients with PBC had significantly higher levels of cholesterol and liver function tests. There were no statistically significant difference in serum insulin and HOMA levels, as well as incidence of MS was diagnosed in 30.9 % (17/55) PBC patients and 43.2 % (19/44) controls. We registered lower amount of VF (PBC:10.92 ± 3.63 mm, CG:16.84 ± 5.51 mm,p < 0.001), VA (PBC:403.64 ± 166.97 mm(2), CG:720.57 ± 272.50 mm(2),p < 0.001), and PF (PBC:7.03 ± 1.82 mm, CG 10.49 ± 2.70 mm,p < 0.001) in patients with PBC.

CONCLUSION

MS is not more frequent in patients with PBC compared with healthy volunteers in our population. Lower amount of VF could be related to lower risk for cardiovascular events in PBC patients.

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.

Ultrasound measurement of visceral fat in patients with primary biliary cirrhosis

Background/Aim. Primary biliary cirrhosis (PBC) is a progressive, chronic liver disease with elevated serum lipids, but it is unclear whether hyperlipidemia in PBC patients is associated with atherosclerosis. Metabolic syndrome promotes development of atherosclerotic cardiovascular disease related to abdominal type obesity and insulin resistance. The aim of our study was to assess abdominal adiposity in patients with PBC. Methods. The study included 40 patients with PBC and 50 healthy controls. Age, sex and anthropometric measurements (weight, height, body mass index and waist circumference) were registered for all patients and controls. We used ultrasonography to measure subcutaneous (SF) and visceral fat (VF) diameter, subcutaneous area (SA) and visceral area (VA), as well as perirenal fat diameter (PF). Results. Values of SF, VF and PF thicknesses in PBC patients were 19.23 ? 5.85 mm, 10.92 ? 3.63 mm, and 7.03 ? 1.82 mm, respectively. In controls these measurements were 22.73 ? 6.70 mm, 16.84 ? 5.51 mm and 10.50 ? 2.70 mm respectively. In PBC patients SA and VA were calculated to 983.64 ? 322.68 mm2 and 403.64 ? 166.97 mm2 and in controls 1124.89 ? 366.01 mm2 and 720.57 ? 272.50 mm2 respectrively. Significant difference was found for VF, VA and RF values. Conclusions. Considering that the amount of visceral fat plays an important role in development of metabolic syndrome and cardiovascular diseases, we concluded that the lower amount of visceral fat in PBC patients could be related to lower incidence of cardiovascular events, despite hyperlipidemia.

Statins in the treatment of dyslipidemia in the presence of elevated liver aminotransferase levels: a therapeutic dilemma

The beneficial role of statins in primary and secondary prevention of coronary heart disease has resulted in their frequent use in clinical practice. However, safety concerns, especially regarding hepatotoxicity, have driven multiple trials, which have demonstrated the low incidence of statin-related hepatic adverse effects. The most commonly reported hepatic adverse effect is the phenomenon known as transaminitis, in which liver enzyme levels are elevated in the absence of proven hepatotoxicity. This class effect is usually asymptomatic, reversible, and dose-related. However, the increasing incidence of chronic liver diseases, including nonalcoholic fatty liver disease and hepatitis C, has created a new challenge when initiating statin treatment in patients with high cardiovascular risk. These diseases result in abnormally high liver biochemistry values, discouraging statin use by clinicians, fostering treatment discontinuation, and leaving a large number of at-risk patients untreated. A PubMed/MEDLINE search of the literature regarding statin safety (January 1, 1994-December 31, 2008) was performed, using the following search terms: statin safety, statin-related hepatotoxicity, and chronic liver disease and statin use, as well as the specific names of different statins and different liver diseases. Relevant clinical trials, review articles, panel discussions, and guideline recommendations were selected. This review supports the use of statin treatment in patients with high cardiovascular risk whose elevated aminotransferase levels have no clinical relevance or are attributable to known stable chronic liver conditions. For each patient, the decision should be based on an individual assessment of risks and benefits.

Use of statins in patients with liver disease

Cardiovascular disease is as common in individuals with chronic liver disease as in the general population. Moreover, recent data suggest that patients with nonalcoholic fatty liver disease (NAFLD) may have a cardiovascular risk greater than that conferred by the conventional risk factors. There is unequivocal evidence that cardiovascular disease is an important cause of morbidity and mortality in this patient population and thus requires consideration of aggressive therapy with lipid-lowering agents such as statins. Because all statins are hepatically cleared and can cause elevations in liver biochemistries, there is a concern that patients with underlying liver disease may be at increased risk for hepatotoxicity. However, recent data, along with an assessment of statin safety by the Liver Expert Panel, suggest that statins are generally well tolerated in patients with chronic liver disease such as NAFLD, primary biliary cirrhosis, and hepatitis C virus. These drugs also appear to be safe in patients with stable/compensated cirrhosis. However, decompensated cirrhosis and acute liver failure should be considered contraindications for lipid-lowering therapy as these patients are unlikely to benefit because of their generally grave prognosis. Although routine hepatic biochemical test monitoring is recommended, the cost-effectiveness of this approach has been questioned. The benefit of statins in patients with underlying liver disease who are otherwise important candidates for statin therapy far outweighs the risk of a very rare event of serious liver injury.

Low-dose atorvastatin improves dyslipidemia and vascular function in patients with primary biliary cirrhosis after one year of treatment

OBJECTIVE

Primary biliary cirrhosis (PBC) is frequently associated with hypercholesterolemia and with an increased cardiovascular morbidity and mortality. Statins lower serum cholesterol levels and may thus improve the cardiovascular risk in PBC patients. The aim of our study was to prospectively examine the efficacy of low-dose atorvastatin on cholestasis as well as cardiovascular risk markers such as dyslipidemia and vascular function in patients with PBC.

METHODS

Nineteen patients with early-stage (biopsy proven and AMA positive) PBC and low-density lipoprotein cholesterol (LDL-C) above 130mg/dL were included in this single-center study and treated with atorvastatin 10mg per day for one year.

RESULTS

Concentrations of total cholesterol, LDL-C, LDL triglycerides, oxLDL, IgG and sVCAM-1 decreased significantly after 48 weeks of atorvastatin treatment. Flow-mediated dilation (FMD) of the brachial artery as an indicator of vascular function significantly increased, while carotid artery intima-media thickness and vascular wall stiffness did not progress under treatment. No statistical differences in liver enzymes were observed except a transient increase of alkaline phosphatase.

CONCLUSION

Treatment with low-dose atorvastatin is safe in early-stage PBC, effectively reduces total cholesterol, LDL-C, LDL triglycerides, oxLDL and sVCAM-1 and improves vascular function as reflected by FMD, without affecting cholestasis progression. Therefore, statin therapy should be considered in PBC patients with additional risk factors for cardiovascular disease.

Primary biliary cirrhosis

Primary biliary cirrhosis (PBC) is an immune-mediated chronic cholestatic liver disease with a slowly progressive course. Without treatment, most patients eventually develop fibrosis and cirrhosis of the liver and may need liver transplantation in the late stage of disease. PBC primarily affects women (female preponderance 9–10:1) with a prevalence of up to 1 in 1,000 women over 40 years of age. Common symptoms of the disease are fatigue and pruritus, but most patients are asymptomatic at first presentation. The diagnosis is based on sustained elevation of serum markers of cholestasis, i.e., alkaline phosphatase and gamma-glutamyl transferase, and the presence of serum antimitochondrial antibodies directed against the E2 subunit of the pyruvate dehydrogenase complex. Histologically, PBC is characterized by florid bile duct lesions with damage to biliary epithelial cells, an often dense portal inflammatory infiltrate and progressive loss of small intrahepatic bile ducts. Although the insight into pathogenetic aspects of PBC has grown enormously during the recent decade and numerous genetic, environmental, and infectious factors have been disclosed which may contribute to the development of PBC, the precise pathogenesis remains enigmatic. Ursodeoxycholic acid (UDCA) is currently the only FDA-approved medical treatment for PBC. When administered at adequate doses of 13–15 mg/kg/day, up to two out of three patients with PBC may have a normal life expectancy without additional therapeutic measures. The mode of action of UDCA is still under discussion, but stimulation of impaired hepatocellular and cholangiocellular secretion, detoxification of bile, and antiapoptotic effects may represent key mechanisms. One out of three patients does not adequately respond to UDCA therapy and may need additional medical therapy and/or liver transplantation. This review summarizes current knowledge on the clinical, diagnostic, pathogenetic, and therapeutic aspects of PBC.

Unstable coronary plaques and cardiac events in myocardial infarction-prone Watanabe heritable hyperlipidemic rabbits: questions and quandaries

PURPOSE OF REVIEW

Use of suitable animal models is essential for investigation of the mechanisms underlying cardiac events and development of the therapeutic strategies; however, ideal animal models that can recapitulate human coronary atherosclerosis and subsequent acute myocardial infarction are still lacking. In this article, we review the insights learned from myocardial infarction-prone Watanabe heritable hyperlipidemic (designated as WHHLMI) rabbits and discuss the possibility of using this model for the study of human acute coronary syndromes.

RECENT FINDINGS

The vulnerable plaques of human coronary arteries are histologically characterized by a large lipid core and a thin fibrous cap with inflammatory cells. Recent studies have revealed that inflammatory cells and inflammatory mediators (such as cytokines and matrix metalloproteinases) play an important role in the plaque rupture.

SUMMARY

We developed the WHHLMI rabbit that shows spontaneous myocardial infarction caused by coronary atherosclerosis. The coronary lesions of WHHLMI rabbits have features of fatty streaks, fibrous plaques, and fibroatheromatous plaques. Some plaques contain a lipid core and a thin fibrous cap similar to human vulnerable plaques. In spite of this, the plaque rupture is not observed in WHHLMI rabbits, suggesting that other additional factors such as mechanical stress are required to trigger the rupture. WHHLMI rabbits may become an important means for elucidating the possible mechanisms of plaque rupture by exposing the plaques to additional risk factors beyond hyperlipidemia.

Risk of cardiovascular and cerebrovascular events in primary biliary cirrhosis: a population-based cohort study

BACKGROUND

Hyperlipidemia is a common finding among patients with primary biliary cirrhosis (PBC). However, whether this results in higher rates of cardiovascular and cerebrovascular events in PBC patients compared with the general population is unclear.

METHODS

We compared the risk of developing myocardial infarction (MI), stroke, and transient ischemic attack (TIA) in a cohort of people with PBC with a general population control cohort matched on age, sex, and general practice (GP). Subjects were selected from the General Practice Research Database (GPRD). Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using Cox regression.

RESULTS

Nine hundred thirty PBC patients (88% female) were compared with 9,202 controls. During a total of about 43,700 person-years of follow-up, 244 MIs, 591 strokes, and 221 TIAs were identified. Incidence rates per 1,000 person-years for MI, stroke, and TIA during the study period were 5.9 (3.9-9.0), 13.8 (10.5-18.2), and 3.5 (2.0-6.0) for PBC cohorts and 5.6 (4.9-6.4), 14.0 (12.9-15.2), and 5.3 (4.6-6.0) for control cohorts, respectively. HRs in PBC cohort compared with the control cohort were for any vascular event 0.99 (95% CI 0.77-1.27) MI 1.04 (95% CI 0.67-1.62), stroke 0.98 (95% CI 0.73-1.31), and TIA 0.66 (95% CI 0.38-1.16). Adjustment for confounders did not change the results substantially.

CONCLUSIONS

PBC was not associated with an increased risk of MI, stroke, or TIA in this cohort. Therefore, strategies for the prevention of vascular events in PBC patients should be similar to those in the general population.