Genotype-specific interactions of insulin resistance, steatosis, and fibrosis in chronic hepatitis C

Effect of achieving sustained virological response with direct-acting antiviral agents on glycemic control in diabetic patients with chronic hepatitis C infection

Background

Hepatitis C virus (HCV) is a significant cause of chronic hepatitis, cirrhosis, and hepatocellular carcinoma worldwide. Liver disease is not the only problem caused by chronic HCV infection; many extrahepatic complications, such as insulin resistance, can be associated with HCV infection. The aim of this study was to assess the effect of achieving a sustained virological response after treatment with directly acting antiviral drugs on insulin resistance in patients with chronic HCV infection.

Results

This prospective study was conducted on 46 HCV patients with type 2 diabetes mellitus who received directly acting antiviral drugs for HCV infections. Fasting insulin, fasting blood glucose, and lipid profiles were assessed in all patients at three time points: before treatment, at the end of treatment, and 12 weeks after the end of treatment. Despite using three different directly acting antiviral drug regimens, all patients achieved a sustained viral response, regardless of the regimen used. the Homeostatic Model Assessment for Insulin Resistance decreased significantly at the end of treatment; however, when recalculated at week 12 after end of treatment, the reduction of the Homeostatic Model Assessment for Insulin Resistance was not significant compared to the baseline levels. Total cholesterol and low-density lipoproteins increased at the end of treatment and continued to increase for 12 weeks after the end of treatment.

Conclusions

Improvements in insulin resistance and glycemic control were noted in HCV patients at the end of treatment with directly acting antiviral drugs; this effect was also apparent after 12 weeks. An increase in the levels of total cholesterol and low-density lipoprotein can be expected after treatment with directly acting antiviral drugs.

Higher dietary insulinaemic potential is associated with increased risk of liver steatosis and fibrosis

BACKGROUND AND AIMS

Hyperinsulinaemia and insulin resistance play a central role in the progression of hepatic steatosis and fibrosis, and diet can modulate insulin response. We thus hypothesised that diet with higher insulinaemic potential is associated with an increased risk of these conditions.

METHODS

Two empirically dietary indices for hyperinsulinaemia (EDIH) and insulin resistance (EDIR) were derived to identify food groups most predictive of fasting concentrations of C-peptide and insulin and homeostatic model assessment for insulin resistance respectively. Hepatic steatosis and fibrosis were defined by controlled attenuation parameter and liver stiffness measurement using transient elastography (TE). Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated by logistic regression.

RESULTS

Of the 4171 participants with TE examination, 1436 (age-standardised prevalence, 33.8%) were diagnosed with steatosis, 255 (5.6%) with advanced fibrosis and 101 (2.2%) with cirrhosis. The multivariable-adjusted ORs for participants comparing the highest to the lowest EDIH tertile were 1.17 (95% CI: 0.99-1.39, P_trend  = .005) for steatosis, 1.74 (95% CI: 1.24-2.44, P_trend  = .001) for advanced fibrosis and 2.05 (95% CI: 1.21-3.46, P_trend  = .004) for cirrhosis. Similar associations were observed for EDIR with ORs of 1.32 (95% CI: 1.11-1.55, P_trend  < .001) for steatosis and 1.43 (95% CI: 1.03-1.99, P_trend  = .006) for advance fibrosis. These positive associations remained among never drinkers and individuals who were free of hepatitis B and/or C.

CONCLUSIONS

Our findings suggest that hyperinsulinaemia and insulin resistance may partially underlie the influence of diet on hepatic steatosis and fibrosis, and highlight the importance of reducing or avoiding insulinaemic dietary pattern.

High blood glucose levels are associated with fibrosis/cirrhosis progression in chronic hepatitis C

Chronic hepatitis C (CHC) leads eventually to liver fibrosis, advanced hepatic disease and related deaths. Therefore, it is very important to assess clinical risk factors associated with rapid CHC and hepatic fibrosis progression. Former studies reported diabetes mellitus synergistic interactions with other host factors to fibrosis progression. Here, we aimed to evaluate the association between elevated blood glucose levels and CHC progression according to METAVIR system in patients chronically infected with HCV-genotype 4 and to evaluate the correlation between elevated glucose levels and liver- and viral-related biochemical parameters. A total of 160 patients with CHC (80 with liver fibrosis and 80 with cirrhosis) and 40 healthy volunteers, negative for HCV, were included. Our results revealed that cirrhotic patients had high (P = .0001) fasting (169.1 ± 50.2 mg/dL), postprandial (208 (123-320) mg/dL), and random (176.8 ± 51 mg/dL) glucose levels compared to patients with liver fibrosis (105.0 ± 32, 120 (105-135), and 113.5 ± 35 mg/dL, respectively). Mean serum fasting, postprandial and random glucose levels were significantly (P = .0001) increased with an increase in fibrosis stages, F1< F2< F3< F4. Blood glucose levels were also significantly (P < .05) correlated with liver disease related biological parameters and HCV-Ab titer. In conclusion, our results highlighted the fibrogenic impact of elevated glucose levels on CHC patients.

Insulin resistance in children with chronic hepatitis C and its association with response to IFN-alpha and ribavirin

OBJECTIVE

The aim of our study was to evaluate the association between insulin resistance and the response to IFN-alpha and ribavirin in pediatric patients with chronic hepatitis C.

METHODS

Twenty-six patients with chronic hepatitis C (mean age: 12.5 ± 1.96 years, M/F:3.33) were included in the study. Fasting glucose, insulin, and C-peptide levels, together with HOMA-IR, HOMA-B, and QUICKI values, were assessed. The association between those parameters and treatment response was determined.

RESULTS

Five (19.2%) of the 26 patients analyzed (2 [21.4%] with treatment response and 3 [16.6%] with no treatment response) had insulin resistance (p=1.00). There were no significant differences between the patients with and without treatment response with respect to fasting glucose, insulin, and C-peptide levels or HOMA-IR, HOMA-B, and QUICKI values (p>0.05).

CONCLUSIONS

No significant association was establihed between insulin resistance and response to IFN-alpha and ribavirin, in children with chronic hepatitis C.

Hepatitis C virus genotypes 1-3 infections regulate lipogenic signaling and suppress cholesterol biosynthesis in hepatocytes

BACKGROUND

Patients with different hepatitis C virus (HCV) genotype infections are associated with varying metabolic disorders. Although alteration of lipid metabolism has been confirmed as a virus-induced metabolic derangement in chronic hepatitis C patients, the impact of various HCV genotypes on hepatic cholesterol metabolism remains elusive. In this study, we thus investigated the HCV genotype-specific lipogenic and cholesterol metabolism profiles in an in vitro cell culture system.

METHODS

We first conducted HCV cell culture system (HCVcc) assays by infecting Huh7.5.1 cells with multiple infection-competent HCV strains, including the genotype 2a JFH1 and JFH1-based intergenotypic recombinants 1b and 3a. We then examined the expression levels of various lipid and cholesterol-related genes.

RESULTS

The data showed that infection with individual HCV genotypes exerted unique gene expression regulatory effects on lipoproteins and cholesterol metabolism genes. Of note, all HCV strains suppressed cholesterol biosynthesis in hepatocytes through downregulating the expression of HMG-CoA reductase (HMGCR) and farnesyl-diphosphate farnesyltransferase 1 (FDFT1) - two essential enzymes for cholesterol biosynthesis. These HCV-mediated inhibitory effects could be reversed by treatment with sofosbuvir, a pangenotypic NS5B inhibitor. In addition, overexpression of HCV genotype 1b, 2a or 3a core protein significantly suppressed HMGCR mRNA transcription and translation, thus diminished cellular cholesterol biosynthesis. Nonetheless, the core protein had no effect on FDFT1 expression.

CONCLUSION

Although HCV infection regulates host lipid metabolism in a genotype-specific manner, its inhibition on hepatocellular cholesterogenic gene expression and total cholesterol biosynthesis is a common effect among HCV genotype 1b, 2a and 3a.

Association Between Visceral Abdominal Fat Accumulation and Severity of Liver Fibrosis in Nondiabetic Individuals Coinfected by Human Immunodeficiency Virus and Hepatitis C Virus

Our primary objective was to assess the independent association between liver fibrosis (LF) and abdominal fat accumulation (AFA) and fatty liver disease (FLD). We also aimed to determine the diagnostic accuracy of AFA and FLD for the prediction of cirrhosis measured using unenhanced low-dose computed tomography (CT). This is a cross-sectional study in stable human immunodeficiency virus (HIV)/hepatitis C virus (HCV)-coinfected patients with active HCV replication. CT was used to quantify fat content in segments III and VI of the liver and AFA. Transient elastometry was used to stage LF. Multivariate logistic regression, receiver operating characteristic curve analysis, and linear mixed model analysis were applied. One hundred fifteen HIV/HCV-coinfected patients were included. Cirrhosis was detected in 20.8% (24 patients). There was a high correlation between anthropometric characteristics and radiological variables. The factors independently associated with cirrhosis were albumin concentration [odds ratio (OR), 0.69; 95% confidence interval (CI), 0.58-0.83; p < .0001] and visceral fat accumulation (OR, 1.02; 95% CI, 1.01-1.04; p = .0003). Multinomial analysis showed that visceral fat area (VFA) was the factor independently associated with stage F2 (OR, 1.02; 95% CI, 1.0-1.03; p < .005) and albumin concentration with stage F3 (OR, 0.75; 95% CI, 0.64-0.89; p < .001). VFA was the only radiological variable with an area under the curve >0.7 for the prediction of cirrhosis. There was no inter- or intraobserver variability in the measurement of AFA; however, high interobserver variability was recorded in the measurement of FLD. The association of VFA with cirrhosis, the high reproducibility of CT for the measurement of VFA, and the ability of VFA to predict cirrhosis make CT a suitable technique for identifying HIV/HCV-coinfected patients for closer surveillance.

Diabetes Mellitus and Risk of Hepatic Fibrosis/Cirrhosis

Development of cirrhosis is two- to threefold greater in patients with diabetes mellitus (DM), and in this setting, the prevalence of cirrhosis is surging worldwide. The present review served to examine clinical ties between DM and liver fibrosis and hepatic cirrhosis and explore related biologic mechanisms. Pathways contributing to various etiologies of cirrhosis in conjunction with DM were key investigative targets.

PNPLA3 gene predicts clinical recovery after sustained virological response in decompensated hepatitis C cirrhosis

Background

Patients with decompensated hepatitis C virus (HCV) cirrhosis experience various outcomes after sustained virological response (SVR), ranging from clinical recovery to further deterioration. We hypothesised that the genetic risk for steatosis, namely the polymorphisms rs738409 of Patatin-like Phospholipase Domain-Containing 3 (PNPLA3), rs58542926 of Transmembrane-6-Superfamily-2 (TM6SF2), and rs641738 of Membrane-bound O-acyltransferase Domain-Containing 7 (MBOAT7), is predictive of recovery.

Methods

We prospectively enrolled 56 patients with Child-Pugh (CPT) B/C cirrhosis who underwent antiviral therapy. The primary outcome was change in CPT score at 12, 24, and 48 weeks after SVR. We used a linear mixed-effects model for analysis.

Results

Forty-five patients (PNPLA3: 21 CC, 19 CG, 5 GG) survived to the first endpoint without liver transplantation. The mean change in CPT score at 12, 24, and 48 weeks was −1.57 (SE=0.30), –1.76 (SE=0.32), and −2.0 (SE=0.36), respectively, among the patients with the PNPLA3 CC genotype and −0.50 (SE=0.20), –0.41 (SE=0.25), and −0.24 (SE=0.27), respectively, among the other 24 patients. After adjustment for baseline characteristics, the PNPLA3 CG/GG genotypes were associated with a 1.29 (SE=0.30, p<0.0001) point higher CPT score. Most of the difference came from differences in hepatic encephalopathy and bilirubin. The results for rs58542926 and rs641738 were not significant.

Conclusion

The PNPLA3 CG/GG genotypes could identify a subgroup of patients with decompensated HCV cirrhosis that had suboptimal clinical recovery despite SVR. An understanding of the genetic factors that influence clinical outcomes will help target patients for liver transplant based on individual genetic risk factors and provide insight leading to new therapeutic approaches.

Elbasvir/grazoprevir and sofosbuvir for hepatitis C virus genotype 3 infection with compensated cirrhosis: A randomized trial

Many direct-acting antiviral regimens have reduced activity in people with hepatitis C virus (HCV) genotype (GT) 3 infection and cirrhosis. The C-ISLE study assessed the efficacy and safety of elbasvir/grazoprevir (EBR/GZR) plus sofosbuvir (SOF) with and without ribavirin (RBV) in compensated cirrhotic participants with GT3 infection. This was a phase 2, randomized, open-label study. Treatment-naive participants received EBR/GZR + SOF + RBV for 8 weeks or EBR/GZR + SOF for 12 weeks, and peginterferon/RBV treatment-experienced participants received EBR/GZR + SOF ± RBV for 12 weeks or EBR/GZR + SOF for 16 weeks. The primary endpoint was HCV RNA <15 IU/mL 12 weeks after the end of treatment (sustained virologic response at 12 weeks [SVR12]). Among treatment-naive participants, SVR12 was 91% (21/23) in those treated with RBV for 8 weeks and 96% (23/24) in those treated for 12 weeks. Among treatment-experienced participants, SVR12 was 94% (17/18) and 100% (17/17) in the 12-week arm, with and without RBV, respectively, and 94% (17/18) in the 16-week arm. Five participants failed to achieve SVR: 2 relapsed (both in the 8-week arm), 1 discontinued due to vomiting/cellulitis (16-week arm), and 2 discontinued (consent withdrawn/lost to follow-up). SVR12 was not affected by the presence of resistance-associated substitutions (RASs). There was no consistent change in insulin resistance, and 5 participants reported serious adverse events (pneumonia, chest pain, opiate overdose, cellulitis, decreased creatinine). High efficacy was demonstrated in participants with HCV GT3 infection and cirrhosis. Treatment beyond 12 weeks was not required, and efficacy was maintained regardless of baseline RASs.

CONCLUSION

Data from this study support the use of EBR/GZR plus SOF for 12 weeks without RBV for treatment-naive and peginterferon/RBV-experienced people with GT3 infection and cirrhosis (ClinicalTrials.gov NCT02601573). (Hepatology 2018;67:2113-2126).

Hepatitis C Virus Infection Increases Risk of Gallstone Disease in Elderly Chinese Patients with Chronic Liver Disease

We investigated possible links between the etiology of liver disease and gallstone risk in Chinese patients with chronic liver disease (CLD). We compared the outcomes of 267 Chinese CLD patients with gallstones and those of a control group of 1,015 CLD patients without gallstones. Logistic regression analyses adjusting for demographic features and other gallstone risk factors revealed that liver cirrhosis increased the risk of gallstone development twofold [adjusted odds ratio (AOR); 95% confidence interval (95% CI): 2.343 (1.710–3.211)]. HCV infection increased gallstone risk 1–2-fold [AOR; 95% CI: 1.582 (1.066–2.347)] higher than did HBV infection. Multivariate analyses of the risk of developing gallstones in patients with liver cirrhosis after an HCV or HBV infection yielded an estimated AOR (95% CI) of 1.601 (1.063–2.413) in patients with an HCV infection. In elderly patients with CLD (≥60 years of age), gallstone risk also increased significantly after an HCV infection [AOR (95% CI): 2.394 (1.066–5.375)]. HCV infection, older age, and liver cirrhosis significantly correlate with an increased risk of gallstone development in Chinese patients with CLD. HCV infection further increases this risk in both patients with liver cirrhosis and in elderly CLD patients (≥60 years of age).

The effect of the TM6SF2 E167K variant on liver steatosis and fibrosis in patients with chronic hepatitis C: a meta-analysis

The impact of Transmembrane 6 superfamily member 2 (TM6SF2) E167K variant, which causes hepatocellular fat retention by altering lipoprotein secretion, on liver damage and metabolic traits in chronic hepatitis C patients is still debated. We performed a systematic review and meta-analysis to clarify this relationship. Four studies with a total of 4325 patients were included. The risk of histologically-determined advanced steatosis, fibrosis, and cirrhosis (but not of severe inflammation) were increased in carriers of the TM6SF2 variant (P < 0.05). Unlike the inconsistent association with steatosis severity, due to the confounding effect of infection by the genotype-3 hepatitis C virus, the TM6SF2 variant was robustly associated with advanced fibrosis (OR = 1.07; 95% confidence interval [CI] = 1.01–1.14) and in particular with cirrhosis (OR = 2.05; 95% CI = 1.39–3.02). Regarding metabolic features, individuals positive for the TM6SF2 variant exhibited 5.8–12.0% lower levels of circulating triglycerides and non-HDL cholesterol (P < 0.05). Carriers of the variant were leaner, but there was high heterogeneity across studies (I² = 97.2%). No significant association was observed between the TM6SF2 variant and insulin resistance or hepatitis C viral load (both P > 0.05). In conclusion, the TM6SF2 E167K variant promotes the development of steatosis, fibrosis and cirrhosis in patients with chronic hepatitis C. Conversely, this variant reduces circulating atherogenic lipid fractions.

Risk Factors for Cholelithiasis

Gallstone disease is one of the most common public health problems in the United States. Approximately 10%-20% of the national adult populations currently carry gallstones, and gallstone prevalence is rising. In addition, nearly 750,000 cholecystectomies are performed annually in the United States; direct and indirect costs of gallbladder surgery are estimated to be $6.5 billion. Cholelithiasis is also strongly associated with gallbladder, pancreatic, and colorectal cancer occurrence. Moreover, the National Institutes of Health estimates that almost 3,000 deaths (0.12% of all deaths) per year are attributed to complications of cholelithiasis and gallbladder disease. Although extensive research has tried to identify risk factors for cholelithiasis, several studies indicate that definitive findings still remain elusive. In this review, predisposing factors for cholelithiasis are identified, the pathophysiology of gallstone disease is described, and nonsurgical preventive options are discussed. Understanding the risk factors for cholelithiasis may not only be useful in assisting nurses to provide resources and education for patients who are diagnosed with gallstones, but also in developing novel preventive measures for the disease.

Diabetes mellitus, insulin resistance and hepatitis C virus infection: A contemporary review

AIM

To summarise the literature data on hepatitis C virus (HCV)-infected patients concerning the prevalence of glucose abnormalities and associated risk.

METHODS

We conducted a PubMed search and selected all studies found with the key words "HCV" or "hepatitis C virus" and "diabetes" or "insulin resistance". We included only comparative studies written in English or in French, published from January 2000 to April 2015. We collected the literature data on HCV-infected patients concerning the prevalence of glucose abnormalities [diabetes mellitus (DM) and insulin resistance (IR)] and associated risk [i.e., severe liver fibrosis, response to antivirals, and the occurrence of hepatocellular carcinoma (HCC)].

RESULTS

HCV infection is significantly associated with DM/IR compared with healthy volunteers and patients with hepatitis B virus infection. Glucose abnormalities were associated with advanced liver fibrosis, lack of sustained virologic response to interferon alfa-based treatment and with a higher risk of HCC development. As new antiviral therapies may offer a cure for HCV infection, such data should be taken into account, from a therapeutic and preventive point of view, for liver and non-liver consequences of HCV disease. The efficacy of antidiabetic treatment in improving the response to antiviral treatment and in decreasing the risk of HCC has been reported by some studies but not by others. Thus, the effects of glucose abnormalities correction in reducing liver events need further studies.

CONCLUSION

Glucose abnormalities are strongly associated with HCV infection and show a negative impact on the main liver related outcomes.

Diabetes Mellitus is Associated With Higher Risk of Developing Decompensated Cirrhosis in Chronic Hepatitis C Patients

GOALS

To investigate the association of diabetes with risk of decompensated cirrhosis in patients with chronic hepatitis C (CHC).

BACKGROUND

Direct-acting antivirals are highly effective in treating CHC but very expensive. CHC patients at high risk of progression to symptomatic liver disease may benefit most from early treatment.

STUDY

We conducted a retrospective cohort study using the 2006 to 2013 Truven Health Analytics MarketScan Commercial Claims and Encounters database including inpatient, outpatient, and pharmacy claims from private insurers. CHC and cirrhosis were identified using ICD-9-CM diagnosis codes; baseline diabetes was identified by diagnosis codes or antidiabetic medications. CHC patients were followed to identify decompensated cirrhosis. Multivariable Cox proportional hazards regression was used to model the risk of decompensated cirrhosis by baseline cirrhosis.

RESULTS

There were 75,805 CHC patients with median 1.9 years follow-up. A total of 10,317 (13.6%) of the CHC population had diabetes. The rates of decompensated cirrhosis per 1000 person-years were: 185.5 for persons with baseline cirrhosis and diabetes, 119.8 for persons with cirrhosis and no diabetes, 35.3 for persons with no cirrhosis and diabetes, and 17.1 for persons with no cirrhosis and no diabetes. Diabetes was associated with increased risk of decompensated cirrhosis in persons with baseline cirrhosis (adjusted hazard ratio=1.4; 95% confidence interval, 1.3-1.6) and in persons without baseline cirrhosis (adjusted hazard ratio=1.9; 95% confidence interval, 1.7-2.1).

CONCLUSIONS

In a privately insured US population with CHC, the adjusted risk of decompensated cirrhosis was higher in diabetic compared with nondiabetic patients. Diabetes status should be included in prioritization of antiviral treatment.

Fibrosis in Chronic Hepatitis C: Correlation between Immunohistochemically-Assessed Virus Load with Steatosis and Cellular Iron Content

AIM

We aimed study impact of hepatocytic viral load, steatosis, and iron load on fibrosis in chronic hepatitis C and role of VEGF and VEGFR overexpression in cirrhotic cases in evolving HCC.

MATERIAL AND METHODS

Total of 120 cases were included from TBRI and Beaujon Hospital as chronic hepatitis C (CHC), post-hepatitis C cirrhosis, and HCC. Cases of CHC were stained for Sirius red, Prussian blue and immunohistochemically (IHC) for HCV-NS3/NS4. HCC were stained IHC for VEGF and by FISH.

RESULTS

Stage of fibrosis was significantly correlated with inflammation in CHC (P < 0.01). Noticed iron load did not correlate with fibrosis. Steatosis was associated with higher inflammation and fibrosis. The cellular viral load did not correlate with inflammation, steatosis or fibrosis. VEGF by IHC was significantly higher in cases of HCC when compared to cirrhotic group (P < 0.001). Amplification of VEGFR2 was confirmed in 40% of cases of HCC. Scoring of VEGF by IHC was the good indicator of VEGFR2 amplification by FISH (P < 0.005).

CONCLUSION

Grade of inflammation is the factor affecting fibrosis in CHC. The degree of liver damage is not related to cellular viral load or iron load. Steatosis is associated with higher inflammation and fibrosis. VEGF by IHC is correlated with overexpression of VEGFR2 by FISH.

The association between chronic hepatitis C infection and cardiovascular risk

BACKGROUND

Vascular disease is a common cause of death in patients with chronic hepatitis C (CHC) infection; however, the association between CHC and atherosclerosis is unclear.

AIMS

To determine whether patients with CHC have increased subclinical vascular disease and whether genotype or antiviral treatment modifies this risk.

METHODS

Fifty CHC patients and 22 age-matched and sex-matched healthy controls underwent clinical and biochemical assessment for vascular risk factors. In addition, vascular risk was assessed by measuring arterial stiffness (aortic augmentation index and carotid-femoral pulse wave velocity (PWV)), endothelial dysfunction (brachial artery flow-mediated dilatation (FMD) and dilatation post-glycerol trinitrate administration) and carotid intima-media thickness (CIMT). Assessment was repeated in subset of CHC patients (n = 12) undergoing antiviral treatment 18 months after initiation of treatment.

RESULTS

Baseline vascular risk factors and measures of arterial stiffness, endothelial dysfunction and CIMT were not different between cases and controls (P > 0.2 for all). Genotype 1 CHC patients had greater endothelial dysfunction with lower FMD (8.2 ± 3.5% vs 10.9 ± 5.2%, P = 0.03) and higher right CIMT (0.6 ± 0.1 mm vs 0.5 ± 0.07 mm, P = 0.04) compared with non-genotype 1. Patients who achieved sustained virological response (7/12) showed significant improvement in insulin resistance (homeostasis model of assessment of insulin resistance 2.3 ± 1.2 vs 1.8 ± 0.8, P = 0.02) and arterial stiffness (PWV 7.4 ± 1.1 m/s vs 6.5 ± 0.6 m/s, P = 0.04).

CONCLUSIONS

Subclinical vascular disease is not greater in CHC subjects compared with controls. However, among CHC subjects, genotype 1 infection is associated with greater endothelial dysfunction and increased carotid-intima medial thickness compared with non-genotype 1 infection. Successful viral eradication may improve insulin resistance and arterial stiffness.

Hepatitis C Virus, Insulin Resistance, and Steatosis

Hepatitis C virus (HCV) is one of the main causes of liver disease worldwide. Liver steatosis is a common finding in many hepatic and extrahepatic disorders, the most common being metabolic syndrome (MS). Over time, it has been shown that the frequent coexistence of these two conditions is not coincidental, since many epidemiological, clinical, and experimental studies have indicated HCV to be strongly associated with liver steatosis and numerous metabolic derangements. Here, we present an overview of publications that provide clinical evidence of the metabolic effects of HCV and summarize the available data on the pathogenetic mechanisms of this association. It has been shown that HCV infection can induce insulin resistance (IR) in the liver and peripheral tissues through multiple mechanisms. Substantial research has suggested that HCV interferes with insulin signaling both directly and indirectly, inducing the production of several proinflammatory cytokines. HCV replication, assembly, and release from hepatocytes require close interactions with lipid droplets and host lipoproteins. This modulation of lipid metabolism in host cells can induce hepatic steatosis, which is more pronounced in patients with HCV genotype 3. The risk of steatosis depends on several viral factors (including genotype, viral load, and gene mutations) and host features (visceral obesity, type 2 diabetes mellitus, genetic predisposition, medication use, and alcohol consumption). HCV-related IR and steatosis have been shown to have a remarkable clinical impact on the prognosis of HCV infection and quality of life, due to their association with resistance to antiviral therapy, progression of hepatic fibrosis, and development of hepatocellular carcinoma. Finally, HCV-induced IR, oxidative stress, and changes in lipid and iron metabolism lead to glucose intolerance, arterial hypertension, hyperuricemia, and atherosclerosis, resulting in increased cardiovascular mortality.

A "systems medicine" approach to the study of non-alcoholic fatty liver disease

The prevalence of fatty liver (steatosis) in the general population is rapidly increasing worldwide. The progress of knowledge in the physiopathology of fatty liver is based on the systems biology approach to studying the complex interactions among different physiological systems. Similarly, translational and clinical research should address the complex interplay between these systems impacting on fatty liver. The clinical needs drive the applications of systems medicine to re-define clinical phenotypes, assessing the multiple nature of disease susceptibility and progression (e.g. the definition of risk, prognosis, diagnosis criteria, and new endpoints of clinical trials). Based on this premise and in light of recent findings, the complex mechanisms involved in the pathology of fatty liver and their impact on the short- and long-term clinical outcomes of cardiovascular, metabolic liver diseases associated with steatosis are presented in this review using a new "systems medicine" approach. A new data set is proposed for studying the impairments of different physiological systems that have an impact on fatty liver in different subsets of subjects and patients.

Treatment of type 2 diabetes mellitus by viral eradication in chronic hepatitis C: Myth or reality?

Chronic hepatitis C is a systemic disease inducing metabolic alterations leading to extrahepatic consequences. In particular, hepatitis C virus (HCV) infection seems to increase the risk of incident type 2 diabetes mellitus in predisposed individuals, independently of liver disease stage. The mechanisms through which hepatitis C induces T2DM involve direct viral effects, insulin resistance, pro-inflammatory cytokines and other immune-mediated processes. Many studies have reported the clinical consequences of type 2 diabetes mellitus on hepatitis C outcome, but very few studies have addressed the issue of microangiopathic complications among patients with hepatitis C only, who develop type 2 diabetes mellitus. Moreover, clinical trials in HCV-positive patients have reported improvement in glucose metabolism after antiviral treatment; recent studies have suggested that this metabolic amelioration might have a clinical impact on type 2 diabetes mellitus-related complications. These observations raise the question as to whether the HCV eradication may also have an impact on the future morbidity and mortality due to type 2 diabetes mellitus. The scope of this review is to summarise the current evidence linking successful antiviral treatment and the prevention of type 2 diabetes mellitus and its complications in hepatitis C-infected patients.

Insulin Resistance is Associated With Significant Liver Fibrosis in Chronic Hepatitis C Patients: A Systemic Review and Meta-Analysis

BACKGROUND

The role of insulin resistance (IR) on fibrosis progression in hepatitis C virus (HCV) patients has not been systematically evaluated. Therefore, this systemic review aimed to summarize the available epidemiologic evidence to evaluate the strength of association between IR and advanced liver fibrosis in these patients.

METHODS

We performed a systemic literature search in PubMed, OvidSP, and MEDLINE from January 1990 to April 2015 without language restriction using the following search terms: insulin resistance, liver fibrosis, cirrhosis, diabetes mellitus, and chronic hepatitis C. Publication bias was assessed using the Begg and Egger tests and with a visual inspection of funnel plot. All analyses were performed using Comprehensive Meta-Analysis, version 2 software.

RESULTS

A total of 3659 participants with HCV infection from 14 studies were included in the analysis. After adjusting for publication bias, the relative risk (RR) for significant hepatic fibrosis among HCV subjects with IR was 1.63 [95% confidence interval (CI), 1.34-2.01]. Subgroup analysis by genotypes showed RR of 2.16 (95% CI, 1.52-3.06) for genotype 1; however, the association was no longer significant when we analyzed the data for HCV genotype 3; RR=1.40 (95% CI, 0.8-2.45).

CONCLUSION

Our study showed significant association between IR and significant hepatic fibrosis in patients with HCV genotype 1 infection.

Evaluation of Dual Therapy in Real Life Setting in Treatment-Naïve Turkish Patients with HCV Infection: A Multicenter, Retrospective Study

BACKGROUND

Before the introduction of direct-acting antivirals in the treatment of chronic hepatitis C patients, the combination of peginterferon alpha and ribavirin was the standard therapy. Observational studies that investigated sustained virological response (SVR) rates by these drugs yielded different outcomes.

AIMS

The goal of the study was to demonstrate real life data concerning SVR rate achieved by peginterferon alpha plus ribavirin in patients who were treatment-naïve.

STUDY DESIGN

A multicenter, retrospective observational study.

METHODS

The study was conducted retrospectively on 1214 treatment naïve-patients, being treated with peginterferon alpha-2a or 2b plus ribavirin in respect of the current guidelines between 2005 and 2013. The patients' data were collected from 22 centers via a standard form, which has been prepared for this study. The data included demographic and clinical characteristics (gender, age, body weight, initial Hepatitis C virus RNA (HCV RNA) level, disease staging) as well as course of treatment (duration of treatment, outcomes, discontinuations and adverse events). Renal insufficiency, decompensated liver disease, history of transplantation, immunosuppressive therapy or autoimmune liver disease were exclusion criteria for the study. Treatment efficacy was assessed according to the patient's demographic characteristics, baseline viral load, genotype, and fibrosis scores.

RESULTS

The mean age of the patients was 50.74 (±0.64) years. Most of them were infected with genotype 1 (91.8%). SVR was achieved in 761 (62.7%) patients. SVR rate was 59.1% in genotype 1, 89.4% in genotype 2, 93.8% in genotype 3, and 33.3% in genotype 4 patients. Patients with lower viral load yielded higher SVR (65.8% vs. 58.4%, p=0.09). SVR rates according to histologic severity were found to be 69.3%, 66.3%, 59.9%, 47.3%, and 45.5% in patients with fibrosis stage 0, 1, 2, 3 and 4, respectively. The predictors of SVR were male gender, genotype 2/3, age less than 45 years, low fibrosis stage, low baseline viral load and presence of early virological response. SVR rates to each peginterferon were found to be similar in genotype 1/4 although SVR rates were found to be higher for peginterferon alpha-2b in patients with genotype 2/3. The number of patients who failed to complete treatment due to adverse effects was 33 (2.7%). The number of patients failed to complete treatment due to adverse effects was 33 (2.7%).

CONCLUSION

Our findings showed that the rate of SVR to dual therapy was higher in treatment-naïve Turkish patients than that reported in randomized controlled trials. Also peginterferon alpha-2a and alpha-2b were found to be similar in terms of SVR in genotype 1 patients.

Association between IL28B polymorphism, TNFα and biomarkers of insulin resistance in chronic hepatitis C-related insulin resistance

TNFα has been shown to play a role in hepatitis C virus (HCV)-induced insulin resistance (IR). Polymorphism of the IL28B gene that encodes IFN-lambda 3 may be associated with IR through modulation of TNFα. The aim of this study was to investigate the relationship between IL28B rs12979860 genotype, the level of TNFα activation and the degree of IR in patients with chronic hepatitis C. One hundred and thirty-three nondiabetic genotype 1 HCV-infected patients with biopsy proven noncirrhotic hepatitis C were investigated for IR (using HOMA index), IL28B rs12979860 genotype and fasting circulating levels of soluble receptor 1 of TNFα (sTNFR1) and adipokines: leptin, adiponectin and IL-6. The HOMA-IR was positively correlated with serum levels of leptin (r = 0.35, P < 0.0001) and sTNFR1 (r = 0.35, P < 0.0001) but not with IL-6 or adiponectin. IL28B rs12979860 CC genotype was observed in 35% patients. Genotype CC and nongenotype CC patients were similar in terms of HOMA-IR (means 1.6 ± 0.9 vs 1.7 ± 1.4) and had similar circulating levels of sTNFR1 and adipokines. Independent factors associated with IR were ferritin (OR = 1.002, P = 0.02), leptin (OR = 1.06, P = 0.02) and sTNFR1 (OR = 7.9, P = 0.04). This study suggests that in nondiabetic, noncirrhotic, HCV genotype 1-infected patients, there is no relationship between IL28B rs12979860 genotype and HOMA-IR or sTNFR1 level. HCV-related IR may be mediated through TNFα independent of IL28B genotype.

Advanced hepatic fibrosis and steatosis are associated with persistent alanine aminotransferase elevation in chronic hepatitis C patients negative for hepatitis C virus RNA during pegylated interferon plus ribavirin therapy

BACKGROUND

Clinical implications of persistent alanine aminotransferase (ALT) elevation and associated factors in chronic hepatitis C (CHC) patients who achieved undetectable hepatitis C virus (HCV) RNA during pegylated interferon plus ribavirin (peg-IFN/RBV) therapy remain unknown.

METHODS

A total of 1113 CHC patients with undetectable HCV RNA during peg-IFN/RBV therapy were enrolled. Baseline characteristics associated with persistent on-treatment ALT elevation (POAE), and its impact on treatment outcomes, were investigated.

RESULTS

Of 1113 CHC patients, 254 (22.8%) had POAE. Among patients with HCV genotype 1 (HCV-1) who had complete early virologic response (EVR) and received 48 weeks of therapy, patients with POAE had a lower rate of sustained virologic response (SVR) than those without POAE (44.1% vs 74.0%; P = .0002). Multivariate analyses showed that body mass index ≥ 27 kg/m(2), ALT level ≥3 times the upper limit of normal, aspartate aminotransferase to platelet ratio index score ≥1.5, hepatic fibrosis ≥F3, and hepatic steatosis ≥S2 were independent factors associated with POAE after viral clearance.

CONCLUSIONS

POAE is common in CHC patients during therapy. HCV-1 patients with POAE have a lower SVR rate to 48-week therapy if they achieve complete EVR. Advanced hepatic fibrosis, obesity, and steatosis are factors associated with POAE in these patients.

Pathogenesis and significance of hepatitis C virus steatosis: An update on survival strategy of a successful pathogen

Hepatitis C virus (HCV) is a successful pathogen on the grounds that it exploits its host’s metabolism to build up viral particles; moreover it favours its own survival by inducing chronic disease and the development of specific anatomic changes in the infected organ. Steatosis, therefore, is associated with HCV infection by necessity rather than by chance alone. Approximately 6% of HCV patients have steatohepatitis. Interestingly, HCV steatosis occurs in the setting of multiple metabolic abnormalities (hyperuricemia, reversible hypocholesterolemia, insulin resistance, arterial hypertension and expansion of visceral adipose tissue) collectively referred to as “hepatitis C-associated dysmetabolic syndrome” (HCADS). General, nonalcoholic fatty liver disease (NAFLD)-like, mechanisms of steatogenesis (including increased availability of lipogenic substrates and de novo lipogenesis; decreased oxidation of fatty substrates and export of fatty substrates) are shared by all HCV genotypes. However, genotype 3 seemingly amplifies such steatogenic molecular mechanisms reported to occur in NAFLD via more profound changes in microsomal triglyceride transfer protein; peroxisome proliferator-activated receptor alpha; sterol regulatory element-binding proteins and phosphatase and tensin homologue. HCV steatosis has a remarkable clinical impact in as much as it is an acknowledged risk factor for accelerated fibrogenesis; for impaired treatment response to interferon and ribavirin; and development of hepatocellular carcinoma. Recent data, moreover, suggest that HCV-steatosis contributes to premature atherogenesis via both direct and indirect mechanisms. In conclusion, HCV steatosis fulfills all expected requirements necessary to perpetuate the HCV life cycle. A better understanding of the physiology of HCADS will likely result in a more successful handling of disease with improved antiviral success rates.

Review article: genetic factors that modify the outcome of viral hepatitis

BACKGROUND

Genetic factors can play an important role for treatment response and disease progression in chronic viral hepatitis.

AIM

To review the influence of host genetic factors on the clinical course as well as on treatment response in patients with viral hepatitis.

METHODS

Review of the literature.

RESULTS

A landmark genome-wide association study (GWAS) identified polymorphisms in the IL28B gene on chromosome 19 (19q13.13) associated with response to therapy with pegylated interferon-α (PEG-IFN) and ribavirin (RBV) and spontaneous viral clearance in acute hepatitis C. Furthermore, IL28B genotype is associated with changes of lipid metabolism and insulin resistance. A further GWAS demonstrated that ITPA genetic variants protect HCV genotype 1 patients from RBV-induced anaemia. Another polymorphism in the patatin-like phospholipase domain containing 3 (PNPLA3) is associated with hepatic steatosis. Difficult-to-treat hepatitis C patients homozygous for GG had an up to five-fold lower chance of viral clearance on PEG/RBV than non-GG patients. In chronic hepatitis B patients treated with PEG-IFN several retrospective analyses of IL28B rs12980275 and rs12979860 genotypes yielded conflicting results which can be explained by the heterogeneity between the study populations. Some variants of the HLA-DP locus (HLA-DPA1 A allele and HLA-DPB1) protect against progression of chronic hepatitis B infection.

CONCLUSIONS

The determination of IL28B polymorphisms may be useful to individualise treatment options when using PEG/RBV based therapies for chronic hepatitis C infection. In contrast, so far identified genetic factors play only a minor role in chronic hepatitis B infection.

A novel fibrosis index comprising a non-cholesterol sterol accurately predicts HCV-related liver cirrhosis

Diagnosis of liver cirrhosis is essential in the management of chronic hepatitis C virus (HCV) infection. Liver biopsy is invasive and thus entails a risk of complications as well as a potential risk of sampling error. Therefore, non-invasive diagnostic tools are preferential. The aim of the present study was to create a model for accurate prediction of liver cirrhosis based on patient characteristics and biomarkers of liver fibrosis, including a panel of non-cholesterol sterols reflecting cholesterol synthesis and absorption and secretion. We evaluated variables with potential predictive significance for liver fibrosis in 278 patients originally included in a multicenter phase III treatment trial for chronic HCV infection. A stepwise multivariate logistic model selection was performed with liver cirrhosis, defined as Ishak fibrosis stage 5–6, as the outcome variable. A new index, referred to as Nordic Liver Index (NoLI) in the paper, was based on the model: Log-odds (predicting cirrhosis) = −12.17+ (age×0.11) + (BMI (kg/m²)×0.23) + (D₇-lathosterol (μg/100 mg cholesterol)×(−0.013)) + (Platelet count (x10⁹/L)×(−0.018)) + (Prothrombin-INR×3.69). The area under the ROC curve (AUROC) for prediction of cirrhosis was 0.91 (95% CI 0.86–0.96). The index was validated in a separate cohort of 83 patients and the AUROC for this cohort was similar (0.90; 95% CI: 0.82–0.98). In conclusion, the new index may complement other methods in diagnosing cirrhosis in patients with chronic HCV infection.

Interaction between hepatitis C virus and metabolic factors

Hepatitis C virus (HCV) infection disrupts the normal metabolism processes, but is also influenced by several of the host’s metabolic factors. An obvious and significantly detrimental pathophysiological feature of HCV infection is insulin resistance in hepatic and peripheral tissues. Substantial research efforts have been put forth recently to elucidate the molecular mechanism of HCV-induced insulin resistance, and several cytokines, such as tumor necrosis factor-α, have been identified as important contributors to the development of insulin resistance in the distant peripheral tissues of HCV-infected patients and animal models. The demonstrated etiologies of HCV-induced whole-body insulin resistance include oxidative stress, lipid metabolism abnormalities, hepatic steatosis and iron overload. In addition, myriad effects of this condition have been characterized, including glucose intolerance, resistance to antiviral therapy, progression of hepatic fibrosis, development of hepatocellular carcinoma, and general decrease in quality of life. Metabolic-related conditions and disorders, such as visceral obesity and diabetes mellitus, have been shown to synergistically enhance HCV-induced metabolic disturbance, and are associated with worse prognosis. Yet, the molecular interactions between HCV-induced metabolic disturbance and host-associated metabolic factors remain largely unknown. The diet and lifestyle recommendations for chronic hepatitis C are basically the same as those for obesity, diabetes, and metabolic syndrome. Specifically, patients are suggested to restrict their dietary iron intake, abstain from alcohol and tobacco, and increase their intake of green tea and coffee (to attain the beneficial effects of caffeine and polyphenols). While successful clinical management of HCV-infected patients with metabolic disorders has also been achieved with some anti-diabetic (i.e., metformin) and anti-lipid (i.e., statins) medications, it is recommended that sulfonylurea and insulin be avoided.

Sustained virological response following chronic hepatitis C treatment is associated with improvement in insulin resistance

BACKGROUND

Insulin resistance (IR) is a key factor in the development of hepatic steatosis and fibrosis in chronic hepatitis C virus infection. Little is known about the impact of viral clearance on IR.

AIM

The aim of this study was to determine the impact of viral clearance on IR.

METHODS

Eighty-six patients treated according to standard clinical practice at an Australian teaching hospital between 2003 and 2007 were prospectively studied. Demographic, biochemical and histological data were collected.

RESULTS

The mean pretreatment homeostatic model assessment-IR (HOMA-IR) was similar in the sustained virological response (SVR) and non-SVR groups (2.7 ± 0.5 and 2.8 ± 0.4, respectively), and both values were consistent with significant IR. There was a significant improvement in HOMA-IR (from 3.0 ± 1.0 to 2.2 ± 0.5, P = 0.04) at the end of treatment in the SVR group only. This trended towards significance at 6 months post-treatment. Multiple regression analysis found improvement in both gamma-glutamyl transpeptidase and alanine aminotransferase predicted improvement in HOMA-IR when controlled for other potential factors (P = 0.01).

CONCLUSIONS

Hepatitis C virus clearance is associated with improvement in IR. Although baseline hepatic fibrosis is a predictor of IR, changes in IR appear to be independent of changes in liver fibrosis. Treatment-related improvement in gamma-glutamyl transpeptidase and alanine aminotransferase seen with improved IR may be a possible marker of reduction of hepatic oxidative stress.

Serum levels of apoptosis inhibitor of macrophage are associated with hepatic fibrosis in patients with chronic hepatitis C

Background

Apoptosis inhibitor of macrophage (AIM) and adipocytokines are involved in the metabolic syndrome, which has been putatively associated with the progression of chronic hepatitis C (CHC). However, the association between these cytokines and CHC is not fully elucidated. The aim of this study is to test whether serum levels of AIM and adipocytokines are associated with histological features, homeostasis model assessment-insulin resistance index (HOMA-IR), or whole body insulin sensitivity index (WBISI) in CHC patients.

Methods

Serum samples were obtained from 77 patients with biopsy-proven CHC. In 39 patients without overt diabetes mellitus, a 75 g oral glucose tolerance test (OGTT) was performed and HOMA-IR and WBISI were calculated.

Results

A serum AIM level of ≥1.2 μg/ml was independently associated with advanced hepatic fibrosis (F2 or F3) (odds ratio [OR], 5.612; 95% confidence interval [CI], 1.103–28.563; P = 0.038) based on a multivariate analysis, but there was no significant association between AIM and hepatic steatosis or inflammation. Furthermore, a serum leptin level of ≥8.6 ng/ml was independently associated with the presence of hepatic steatosis (≥5%) (OR, 6.195; 95% CI, 1.409–27.240; P = 0.016), but not hepatic fibrosis or inflammation. No relationship was observed between levels of adiponectin or resistin and hepatic histological parameters based on a multivariate analysis. Although serum levels of leptin, resistin, and adiponectin were significantly correlated with HOMA-IR and WBISI, there was no significant relationship between serum AIM levels and HOMA-IR or WBISI, respectively.

Conclusion

High serum levels of AIM in CHC patients are potentially related to advanced hepatic fibrosis. AIM and adipocytokines are possibly associated with pathological changes via a different mechanism.

Association between insulin resistance and sustained virologic response in hepatitis C treatment, genotypes 1 versus 2 and 3: systematic literature review and meta-analysis

Background/aims

Controversial results have been found in literature for the association between insulin resistance and sustained virologic response to standard chronic hepatitis C treatment. This study aims to provide a systematic literature review with meta-analysis, in order to evaluate if insulin resistance interferes with sustained virologic response in patients infected by the HCV genotype 1 versus HCV genotypes 2 and 3, undergoing treatment with interferon and ribavirin or pegylated interferon and ribavarin.

Methods

Systematic search was performed on main electronic databases until May 2012. Primary outcome was sustained virologic response, defined as undetectable levels of HCV-RNA six months after the end of treatment. Meta-analytic measure was estimated using Dersimonian and Laird's method, using Stata software.

Results

Thirteen studies involving 2238 infected patients were included. There was a statistically significant association between insulin resistance and lower sustained virologic response rate, and this difference occurred in HCV genotype G1 (OR: 2.23; 95% CI: 1.59–3.13) and G2/G3 (OR: 4.45; 95% CI: 1.59–12.49). In addition, a difference was seen in the cut-offs used for defining insulin resistance by Homeostasis Model Assessment of Insulin Resistance. To minimize this limitation, sub-analysis that excluded the studies that did not use 2 as a cut-off value was performed and the results still demonstrated association between insulin resistance and sustained virologic response, for both genotypic groups.

Conclusion

This meta-analysis provides evidence that elevated Homeostasis Model Assessment of Insulin Resistance is associated with a lower sustained virologic response rate in patients with hepatitis C treated with interferon and ribavirin or pegylated interferon and ribavarin, regardless of their genotype.

Metabolic factors and chronic hepatitis C: a complex interplay

In the last years, several lines of evidence showed how metabolic factors may influence the natural history of patients with chronic hepatitis C. Chronic HCV infection is able to perturb the metabolic homeostasis of the host, in a context of complex interactions where pre-existent metabolic status and genetic background play an important role, allowing us to state that HCV infection is a systemic disease. In this review, we discuss the most recent lines of evidence on the main metabolic factors that are known to be associated with CHC, namely, insulin resistance/type 2 diabetes, steatosis, visceral obesity, atherosclerosis, vitamin D, menopause, fructose and coffee intake, lipoproteins, methylenetetrahydrofolate reductase status, and hyperuricaemia. In particular, we focus on the pathophysiological mechanisms underlying the correlation between HCV infection and metabolic disorders, the impact of metabolic factors on the progression of liver and non-liver-related diseases, and, on the contrary, the possible influence of chronic HCV infection on metabolic features. In this setting, the importance of a multifaceted evaluation of CHC patients and a prompt correction of modifiable metabolic risk factors should be emphasized.

Prevalence of type 2 diabetes mellitus in hepatitis C virus infected population: a Southeast Asian study

PURPOSE

The study was aimed to investigate the frequency of diabetes mellitus type 2 in patients infected with chronic hepatitis C virus and its association with cirrhosis.

PATIENTS AND METHODS

This prospective case series was conducted at Section of Gastroenterology and Hepatology, Isra University Hospital, Hyderabad, over a period of 4 months from June 2009 to October 2009. Hepatitis C virus seropositive patients who were older than 18 years, diabetic or nondiabetic, were included. Basic demographic data collected by questionnaire and laboratory investigations including fasting blood glucose levels, serum cholesterol, and liver function tests were done. A logistic regression model was used to explore the association between diabetic and nondiabetic HCV seropositives and type 2 diabetes mellitus with cirrhosis.

RESULTS

A total of 361 patients with hepatitis C were analyzed; the prevalence of type 2 diabetes mellitus in HCV patients was 31.5%. Out of the total number of the participants, 58.4% (n = 211) were cirrhotics, while 41.6% (n = 150) were noncirrhotic HCV seropositives. In multivariate analysis, cirrhotic patients appeared significantly more likely (P = 0.01) to be diabetic as compared with noncirrhotic patients (OR = 2.005, 95% CI: 1.15, 3.43).

CONCLUSION

Advancing age, increased weight, and HCV genotype 3 are independent predictors of type 2 diabetes in HCV seropositive patients, and there is a statistically significant association of cirrhosis observed with type 2 diabetes mellitus.

Host factors determining the efficacy of hepatitis C treatment

Combination therapy with pegylated interferon and ribavirin is the standard of care (SOC) for the treatment of chronic hepatitis C (CHC). Treating CHC with SOC may show a sustained virological response (SVR) in approximately 50-70 % of genotype 1 CHC patients and an SVR in 70-90 % of genotype 2 CHC patients. The genotype, baseline viral load, and viral kinetics (i.e., rapid virologic response and early virologic response) can be used as predictors of response-guided therapy. Nonetheless, host factors, e.g. age, ethnicity, insulin resistance, and genetic variations, may also play important roles in the SVR in CHC patients treated with SOC. Recent genome-wide association studies have demonstrated that single-nucleotide polymorphisms near the interleukin 28B gene (IL28B) were associated with SVR to treatment with SOC in CHC patients. The IL28B polymorphisms may contribute to the viral kinetics during treatment. Asian people have favorable IL28B polymorphisms. This factor may at least partly explain the high eradication rate of hepatitis C by SOC in Asia. Combination therapy with direct-acting antivirals (DAAs) and SOC can increase the SVR rates both in treatment-naïve and treatment-experienced patients. Although the IL28B polymorphisms also affect the SVR of triple therapy with SOC and first-generation protease inhibitors, pilot studies have demonstrated that potent DAAs might overcome the influence of IL28B polymorphisms. Thus, the treatment of hepatitis C virus infection could be simplified in the near future.

Oxidative stress is closely associated with insulin resistance in genotypes 1 and 3 chronic hepatitis C

BACKGROUND

Chronic hepatitis C (CHC) infection is associated with insulin resistance and with oxidative stress, but the relationship between the two has not been thoroughly examined.

PURPOSE

To evaluate the association between insulin resistance and oxidative stress in CHC patients.

METHOD

In 115 CHC patients (68 with genotype 1 and 47 with genotype 3), the relationship between the serum concentration of malondialdehyde (MDA), a marker of oxidative stress and insulin resistance as defined by the homeostasis model (HOMA-IR) was examined.

RESULTS

There was no significant difference in MDA levels between genotype 1- and genotype 3-infected subjects (12.882 vs. 12.426 ng/mL, p = 0.2). By univariate analysis, factors associated with HOMA-IR in both genotypes were oxidative stress as measured by MDA (p = 0.002), body mass index (BMI), portal activity, and fibrosis. Genotype-specific differences in HOMA-IR association were steatosis and triglycerides (TG) for genotype 1, and age and glutathione (GSH) for genotype 3. In a stepwise multiple linear regression analysis in both genotypes, MDA was a significant and independent predictor of HOMA-IR (p = 0.04). As expected, BMI and fibrosis were likewise independently correlated to HOMA-IR. In addition, MDA levels were higher (p < 0.001) and GSH levels were lower (p = 0.023) in insulin-resistant subjects compared to their insulin-sensitive counterparts.

CONCLUSIONS

It is concluded that in CHC, oxidative stress is an independent predictor of HOMA-IR, irrespective of virus genotype. Further studies on the role of oxidative stress in the development of insulin resistance in CHC are warranted.

IL28B polymorphism as a predictor of antiviral response in chronic hepatitis C

AIM

To evaluate the effect of single nucleotide polymorphisms of interleukin (IL)-28B, rs12979860 on progression and treatment response in chronic hepatitis C.

METHODS

Patients (n = 64; 37 men, 27 women; mean age, 44 ± 12 years) with chronic hepatitis C, genotype 1, received treatment with peg-interferon plus ribavirin. Genotyping of rs12979860 was performed on peripheral blood DNA. Histopathological assessment of necroinflammatory grade and fibrosis stage were scored using the METAVIR system on a liver biopsy sample before treatment. Serum viral load, aminotransferase activity, and insulin level were measured. Insulin resistance index, body mass index, waist/hip ratio, percentage of body fat and fibrosis progression rate were calculated. Applied dose of interferon and ribavirin, platelet and neutrophil count and hemoglobin level were measured.

RESULTS

A sustained virological response (SVR) was significantly associated with IL28B polymorphism (CC vs TT allele: odds ratio (OR), 25; CC vs CT allele: OR, 5.4), inflammation activity (G < 1 vs G > 1: OR, 3.9), fibrosis (F < 1 vs F > 1: OR, 5.9), platelet count (> 200 × 10(9)/L vs < 200 × 10(9)/L: OR, 4.7; OR in patients with genotype CT: 12.8), fatty liver (absence vs presence of steatosis: OR, 4.8), insulin resistance index (< 2.5 vs > 2.5: OR, 3.9), and baseline HCV viral load (< 10(6) IU/mL vs > 10(6) IU/mL: OR, 3.0). There was no association with age, sex, aminotransferases activity, body mass index, waist/hip ratio, or percentage body fat. There was borderline significance (P = 0.064) of increased fibrosis in patients with the TT allele, and no differences in the insulin resistance index between groups of patients with CC, CT and TT alleles (P = 0.12). Spearman's rank correlation coefficient between insulin resistance and stage of fibrosis and body mass index was r = 0.618 and r = 0.605, respectively (P < 0.001). Significant differences were found in the insulin resistance index (P = 0.01) between patients with and without steatosis. Patients with the CT allele and absence of a SVR had a higher incidence of requiring threshold dose reduction of interferon (P = 0.07).

CONCLUSION

IL28B variation is the strongest host factor not related to insulin resistance that determines outcome of antiviral therapy. Baseline platelet count predicts the outcome of antiviral therapy in CT allele patients.

The interaction between insulin resistance, liver fibrosis and early virological response in Egyptian patients with chronic hepatitis C

BACKGROUND

Hepatitis C virus (HCV) infection may induce insulin resistance (IR) irrespective of the severity of liver disease, and there is evidence of a central role for IR in failure to achieve sustained virological response (SVR) in HCV patients.

OBJECTIVE

To assess IR as a predictor of the severity of hepatic fibrosis in Egyptian HCV patients, and its effect on early viral kinetics and virological response to HCV therapy.

METHODS

A total of 140 chronic HCV patients were divided into two groups according to the homeostasis model assessment-IR (HOMA-IR). Group 1 consisted of 48 chronic HCV patients with HOMA-IR >=2, and group 2 consisted of 92 chronic HVC patients without IR (HOMA IR <2). All patients were treated with combination therapy (pegylated interferon-alpha 2a plus ribavirin) for 48 weeks and studied for viral kinetics throughout the period of therapy.

RESULTS

The study revealed that older age, higher body mass index and HOMA-IR >=2 were significantly associated with advanced fibrosis. Rapid virological response, complete early virological response and SVR were significantly lower in the IR-HCV group compared with the non-IR-HCV group. Univariate and multivariate analyses revealed that older age, fibrosis (F>=3), high viral load (>600,000 IU⁄mL) and HOMA-IR >=2 were significantly associated with a lack of viral kinetics as well as SVR. However, HOMA-IR >=2 was the main independent variable associated with lack of SVR. On the other hand, body mass index, plasma insulin level and HOMA-IR decreased significantly compared with starting levels in patients who achieved SVR. This suggests a cause and effect relationship between HCV infection and IR.

CONCLUSION

IR in chronic HCV patients is associated with progressive fibrosis and slow viral kinetics, and could be a predictor for lack of rapid and early virological response. Therefore, HOMA-IR levels should be measured and improved before starting antiviral treatment.

Association of the IL28B genotype with insulin resistance in patients with chronic hepatitis C

BACKGROUND & AIMS

Insulin resistance, fibrosis and steatosis are established predictors of response to peg-interferon/ribavirin therapy in chronic hepatitis C (CHC). Several host genetic polymorphisms (IL28B, PNPLA3) modify treatment-outcome, the degree of steatosis or fibrosis. The aim of our study was to evaluate the role of these polymorphisms on insulin resistance (IR) in treatment-naïve patients with chronic hepatitis C.

METHODS

Two hundred and two non-diabetic CHC patients (GT1: 181, GT4: 21; m = 126, f = 76) undergoing liver biopsy in two tertiary academic centers were studied. The SNPs rs12979860 (IL28B) and rs738409 (PNPLA3) were investigated by RT-PCR. HOMA-IR, BMI, stage of fibrosis, extent of steatosis, and genetic data were analyzed.

RESULTS

Insulin resistance (HOMA-IR ≥ 3.0) was associated with rs12979860 genotype, presence of advanced fibrosis, and higher BMI. HOMA-IR in CC and in TC/TT was 2.08 ± 1.61 (mean ± SD) and 2.94 ± 2.89 (p=0.041), respectively. HOMA-IR was higher in advanced than in mild fibrosis (F3-4: 3.92 ± 3.15; F0-2: 2.38 ± 2.38; p=0.004). The percentage of steatotic hepatocytes was higher in patients with advanced fibrosis (21.3 ± 21.5 vs. 9.1 ± 14.2; p<0.001), HOMA-IR ≥ 3.0 (17.7 ± 17.8 vs. 8.8 ± 15.4%; p<0.001), and BMI > 25.0 kg/m(2) (14.7 ± 17.0 vs. 9.1 ± 16.1; p<0.001). The rs738409 GG genotype was associated with advanced fibrosis and steatosis, but not with HOMA-IR. Multivariable logistic regression identified advanced fibrosis (OR: 2.820, 95% CI: 1.344-5.917; p = 0.006) and the IL28B genotype non-CC (OR: 3.000, 1.348-6.676; p = 0.007) as independent risk factors for insulin resistance.

CONCLUSIONS

Insulin resistance is more common in carriers of the T allele of SNP rs12979860 than in CC homozygotes and may partly explain the poor outcome of peginterferon/ribavirin therapy in these patients.

[Chronic hepatitis C and insulin resistance]

Insulin resistance is frequently associated with chronic liver disease, and the interaction between hepatitis C virus (HCV) infection and insulin resistance is a major public health issue, bound to increase in the near term. Because of their potential synergism on liver disease severity, a better understanding of the clinical consequences of the relationship between HCV infection and insulin resistance is needed. This translates into accelerated liver disease progression, reduced response to anti-viral agents and, in susceptible individuals, increased risk of developing type 2 diabetes. HCV may also cause hepatic steatosis, especially in patients infected with genotype 3, although the clinical impact of viral steatosis is debated. Little is known regarding the effect of anti-diabetic agents on HCV infection, and a possible association between use of exogenous insulin or a sulfonylurea agents and the development of hepatocellular carcinoma has recently been reported. Thus, modified lifestyle and pharmacological modalities are urgently warranted in chronic hepatitis C with metabolic alterations.

A prospective evaluation of the role of transient elastography for the detection of hepatic fibrosis in type 2 diabetes without overt liver disease

BACKGROUND

Type 2 diabetes mellitus (T2DM) is a major risk factor for the development of non-alcoholic fatty liver disease (NAFLD) and subsequently hepatic fibrosis. Transient elastography (TE) is a rapid, reproducible non-invasive test that may be appropriate as a screening tool for the presence of hepatic fibrosis.

AIM

Assess the utility of TE as a screening tool for the presence of hepatic fibrosis in a T2DM population with no known liver disease.

METHODS

T2DM patients without known liver disease were included. Patients were assessed with TE in addition to biochemical parameters.

RESULTS

A successful TE evaluation could be obtained in 74 of 81 (91%) included subjects. Of these, 26 (35%) had a liver stiffness measurement (LSM) ≥ 7.65 kPa. Sixteen of these subjects had confirmatory liver biopsies with significant (≥ F2 fibrosis) present in 12 (75%) and cirrhosis diagnosed in 2 subjects. 15/16 (94%) had histological steatohepatitis. Compared with those with a lower LSM, subjects with an LSM ≥ 7.65 kPa had higher ALT levels (38.0 ± 21.7 vs 26.1 ± 11.1 U/L, p = 0.021) and increased prevalence of hepatic steatosis by ultrasound (85% vs 63%, p = 0.005).

CONCLUSION

Significant hepatic fibrosis in the T2DM population is frequently under-recognized. TE may be a feasible tool for the screening of T2DM patients for the presence of hepatic fibrosis.

Type 2 diabetes mellitus and chronic hepatitis C: which is worse? Results of a long-term retrospective cohort study

BACKGROUND

The long-term outcome in patients with chronic hepatitis C and type 2 diabetes mellitus treated with interferon and ribavirin is unclear. We compared incidence of liver-related events and mortality rates between hepatitis C virus-positive patients with or without diabetes mellitus, and the incidence of diabetes-related events between diabetic patients with and without hepatitis C.

METHODS

Retrospective study of 309 patients with chronic hepatitis C. Incidence of liver-related events, diabetes-related events and mortality rates were assessed over a mean follow-up of 11.02±4.9 years.

RESULTS

50 (16%) chronic hepatitis C patients had diabetes mellitus. Diabetics showed a higher number of diabetes- and liver-related events than non-diabetics (10% vs 1.5%, p=0.006; 18% vs 5.7%, p=0.007, respectively) with a mortality of 14% vs 1.5% (p=0.0003). Baseline cirrhosis (p=0.002) and non-sustained virological response (p=0.01) were independent risk factors for liver events; diabetes mellitus (p=0.01) and hypertension (p=0.0017) were independent factors for diabetes-related events.

CONCLUSIONS

In patients with chronic hepatitis C, comorbidity with diabetes mellitus was associated with a higher mortality rate and incidence of liver/diabetes-related events. Independent risk factors for liver-related events were the non-response to antiviral therapy and cirrhosis at baseline.

Diabetes mellitus following liver transplantation in patients with hepatitis C virus: risks and consequences

Recurrent hepatitis C virus (HCV) infection of the allograft occurs universally following liver transplantation. Longitudinal natural history studies have identified several pre- and posttransplant factors associated with more rapid fibrosis progression, including baseline host and viral factors, donor factors and posttransplant immunosuppression effects, such as metabolic syndrome. Evidence accumulated over the past two decades indicates that HCV has metabolic associations, in particular insulin resistance and diabetes mellitus. Approximately half of HCV-positive liver transplant recipients develop posttransplant diabetes mellitus (PTDM), which is associated with accelerated fibrosis progression and poorer graft and patient survival outcomes. This review summarizes the risks and consequences of insulin resistance and PTDM in HCV-positive liver transplant recipients. Risk for developing PTDM is one factor that should be considered when choosing the primary immunosuppressive regimen following liver transplantation. Comparative studies suggest that cyclosporine A-based immunosuppression may provide improved responses to antiviral therapy and reduced incidence of PTDM compared with tacrolimus-based immunosuppression. Addressing insulin resistance and PTDM in HCV-positive liver transplant recipients may have the potential to slow HCV complications and improve survival outcomes.

Impact of HCV genetic differences on pathobiology of disease

Multiple HCV genotypes have been isolated worldwide. Genotype seems to be involved in the main pathological aspects of HCV infection. Insulin resistance, steatosis and progression toward cirrhosis, fibrosis and hepatocellular carcinoma establish and develop following genotype-specific mechanisms. Moreover genotype influences pharmacological treatment in term of dose and duration. Pathways involved in cell proliferation, apoptosis, lipid metabolism, insulin and interferon signaling are impaired to a different extent among genotypes, leading to distinct pathological settings. Genotype 1 is associated with a more aggressive disease with increased insulin resistance, worst response to therapy, higher risk of cirrhosis and hepatocellular carcinoma development, while genotype 3 is associated with increased steatosis and fibrosis. The identification and characterization of HCV types and subtypes provides insight into the different outcome of HCV infection and responsiveness to therapy. In the present article, we focused on the pathogenicity of HCV genotypes and their effect on disease progression and treatment.

Hepatic steatosis at 1 year is an additional predictor of subsequent fibrosis severity in liver transplant recipients with recurrent hepatitis C virus

Recurrent hepatitis C virus (HCV) is the most common cause of graft loss for HCV-infected recipients of liver transplantation (LT). Diabetes mellitus (DM) has been associated with increased rates of fibrosis progression, but whether steatosis affects post-LT outcomes independently of DM is unclear. Using a retrospective cohort of HCV-infected LT recipients, we determined the prevalence of hepatic steatosis and evaluated the relationship between steatosis on index biopsy 1 year after LT (± 6 months) and the severity of the subsequent fibrosis. One hundred fifty-two LT recipients with HCV were followed up for a median of 2.09 years (range = 0.13-6.17 years) after index biopsy; the median number of biopsy procedures per patient after index biopsy was 2 (range = 1-6). Steatosis (≥ 5%) was present in 45 individuals (29.6%) according to index biopsy samples taken 1 year after LT; the steatosis was mild (grade 1) in 80% of the patients. In the multivariate analysis, the presence of steatosis 1 year after LT was positively associated with HCV genotype 3 [odds ratio (OR) = 3.60, P = 0.02], older donor age (OR = 1.03, P = 0.04), and pre-LT hypertension (OR = 3.29, P = 0.009). Two years after index biopsy, the cumulative rate of significant fibrosis (F2-F4 on the Ludwig-Batts scale) was 49% in the patients with steatosis at 1 year and 24% in the patients without steatosis (P = 0.003). In the multivariate analysis, steatosis at 1 year was an independent predictor of subsequent F2 to F4 fibrosis (HR = 2.63, 95% CI = 1.49-4.63). Steatosis was a stronger predictor of fibrosis in the setting of sirolimus use (hazard ratio = 9.38, 95% confidence interval = 1.37-64.16, P = 0.02). In conclusion, steatosis is frequent in the early post-LT period, and steatosis within the first year after LT is a marker of a higher risk of fibrosis progression in HCV-infected patients.