Insulin resistance impairs sustained response rate to peginterferon plus ribavirin in chronic hepatitis C patients

Hepatitis C virus infection: molecular pathways to metabolic syndrome

Chronic infection with hepatitis C virus (HCV) can induce insulin resistance (IR) in a genotype-dependent fashion, thus contributing to steatosis, progression of fibrosis and resistance to interferon therapy. The molecular mechanisms in genotype 1 patients that lead to metabolic syndrome are still ambiguous. Based on our current understanding, HCV proteins associate with mitochondria and endoplasmic reticulum and promote oxidative stress. The latter mediates signals involving the p38 mitogen-activated protein kinase and activates nuclear factor kappa B. This transcription factor plays a key role in the expression of cytokines, tumor necrosis factor alpha (TNF-alpha), interleukin 6, interleukin 8, tumor growth factor beta, and Fas ligand. TNF-alpha inhibits the function of insulin receptor substrates and decreases the expression of the glucose transporter and lipoprotein lipase in peripheral tissues, which is responsible for the promotion of insulin resistance. Furthermore, reduced adiponectin levels, loss of adiponectin receptors, and decreased anti-inflammatory peroxisome proliferator-activated receptor alpha in the liver of HCV patients may contribute to reduced fatty acid oxidation, inflammation, and eventually lipotoxicity. This chain of events may be initiated by HCV-associated IR and provides a direction for future research in the areas of therapeutic intervention.

Dysmetabolic changes associated with HCV: a distinct syndrome?

Although not associated with the metabolic syndrome, HCV is linked with impaired insulin signalling, insulin resistance, hypocholesterolemia and steatosis which represent a distinct HCV-associated dysmetabolic syndrome. Insulin resistance affects the development of diabetes, fibrosis, impaired response to antivirals and perhaps hepatocellular carcinoma risk. HCV infection is associated with hypocholesterolemia and steatosis reversible after sustained virologic response. A "viral", and a "metabolic" steatosis exist as function of viral genotypes. Little is known about the possible role of HCV in further components of the metabolic syndrome such as atherosclerosis, obesity, arterial hypertension, hyperuricemia and thrombotic risk factors.

Effect of sustained virological response to treatment on the incidence of abnormal glucose values in chronic hepatitis C

BACKGROUND/AIMS

To investigate the effect of sustained virological response (SVR) on impaired fasting glucose (IFG) and/or type 2 diabetes (T2DM); to assess the influence of glucose abnormalities on the SVR rate.

METHODS

1059 patients with chronic HCV; normal glucose (< 100 mg/dl) in 734, IFG (between 100 and 125 mg/dl) in 218, and T2DM (126 mg/dl) in 107 cases, were treated with interferon plus ribavirin over 24 or 48 weeks, depending on viral genotype.

RESULTS

The SVR rate was lower in patients with IFG and/or T2DM than in patients with normal glucose concentrations [143/325 (44%) vs. 432/734 (58.8%); P=0.002]. In the follow-up, abnormal glucose concentrations were observed in 74 of 304 (24.3%) non-responders and in 49 of 430 (11.4%) sustained responders (log-rank: 13.8; P=0.00002). Reverse stepwise logistic regression analysis identified the independent variables predictive of IFG or T2DM development as: sustained response (OR: 0.44; 95%CI=0.20-0.97; P=0.004) and fibrosis stage (OR: 1.46; 95%CI=1.06-2.01;P=0.02). Family history of DM, steatosis, gender, HCV viral load, genotype, triglycerides, cholesterol and BMI did not enter the multivariate analysis equation.

CONCLUSIONS

SVR reduces the risk of IFG and/or T2DM development in patients with chronic hepatitis C while altered glucose metabolism impairs sustained response to viral treatment.

Latinos and chronic hepatitis C: a singular population

Latinos are the largest minority in the USA and have higher rates of HCV infection. The course of chronic hepatitis C in Latinos is more aggressive, with higher risk to develop cirrhosis than any other ethnic group or race. Available information suggests that more rapid progression of liver disease is aggravated by decreased efficacy to treatment with available therapies. The causes for more aggressive progression and decreased efficacy of treatment are complex. Factors related to metabolic syndrome, insulin resistance, and hepatic steatosis are important, as well as genetic differences, not only for metabolic syndrome but for immune responses to interferon. In addition, there are substantial barriers for Latinos to access medical care. Language, cultural differences, and socioeconomic factors, including lack of medical insurance, more frequent use of alcohol, and possible medical care provider bias, are significant obstacles to diagnosis and treatment. The severity of the liver disease and the association to metabolic syndrome medical conditions justify that Latinos be considered a special population with urgent need of intervention strategies. In this article we present all the available evidence on epidemiology, natural history of chronic hepatitis C, and efficacy of anti-HCV therapy in Latinos infected with HCV.

Disease progression in chronic hepatitis C: modifiable and nonmodifiable factors

The hepatic complications of chronic hepatitis C (CHC) usually occur only after progression to cirrhosis has taken place. Progression to cirrhosis, however, is extremely variable and depends on a broad set of host and viral factors that modify the rate at which fibrosis develops in a given individual. Despite their inherent limitations, studies of the natural history of CHC have identified several nonmodifiable factors associated with disease progression. These include age at acquisition of infection, sex, and race. More recent reports suggest important roles for host genetic polymorphisms and viral factors. Of greater immediate relevance to patients and their clinicians are the potentially modifiable factors, which include excessive alcohol consumption; smoking (tobacco and marijuana); insulin resistance; and coinfection with hepatitis B virus, human immunodeficiency virus type 1, or schistosomiasis. Unfortunately, to date, there are no reliable predictive models that can accurately estimate the risk of CHC disease progression.

Insulin resistance and diabetes increase fibrosis in the liver of patients with genotype 1 HCV infection

OBJECTIVES

Metabolic factors may affect the course of chronic hepatitis C (CHC). Insulin resistance (IR) determines steatosis, but its direct role in affecting progression of hepatic fibrosis is less clear. We aimed to assess whether increasing degrees of IR, up to overt diabetes, are linked to steatosis and higher stages of fibrosis in patients with CHC resulting from genotype 1 HCV (G1-HCV).

METHODS

Two hundred one consecutive patients with G1-HCV infection were evaluated by liver biopsy and anthropometric and metabolic measurements, including IR, by the homeostasis model assessment (HOMA). Nondiabetic patients were defined as insulin resistant if HOMA-IR was >2.7. All biopsies were scored by one pathologist for staging and grading (Scheuer), and graded for steatosis.

RESULTS

Ninety-six patients were noninsulin resistant (group 1), 76 were insulin resistant without diabetes (group 2), and 29 were diabetic (group 3). At multivariate analysis, fibrosis of >/=3 was independently associated with high necroinflammatory activity (odds ratio [OR] 2.994, 95% confidence interval [CI] 1.422-6.098), low platelets (OR 0.994, 95% CI 0.981-0.999), low cholesterol (OR 0.987, 95% CI 0.976-0.998), high ferritin (OR 1.002, 95% CI 1.001-1.004), and a high prevalence of IR (OR 2.692, 95% CI 1.463-4.954). Diabetic patients were twice as likely to have severe fibrosis (60%) than those with IR but no diabetes (30%) (P= 0.006). The degree of steatosis and that of fibrosis were weakly associated with each other (P= 0.42).

CONCLUSIONS

In subjects with CHC resulting from G1-HCV, IR and overt diabetes are major determinants of advanced fibrosis, regardless of the degree of steatosis, mainly in the presence of severe necroinflammation.

Hepatic steatosis in HIV/HCV co-infected patients: correlates, efficacy and outcomes of anti-HCV therapy: a paired liver biopsy study

BACKGROUND/AIMS

Hepatic steatosis is caused by the complex interaction of host and viral factors, such as metabolic syndrome (MS), alcoholism and HCV genotype, and in HIV-HCV co-infected patients, antiretroviral therapy may also play a role. A large population of patients from the AIDS Pegasys Ribavirin International Co-infection Trial (APRICOT) had paired liver biopsies interpreted and graded for steatosis along with lipid measurements and anthropometric data.

METHODS

We analyzed these patients to determine the prevalence of steatosis, baseline factors associated with steatosis, effect of steatosis in HCV therapy efficacy and the impact of anti-HCV treatment on steatosis.

RESULTS

A total of 65/283 (23%) patients with paired biopsies were positive for steatosis. Patients with steatosis were significantly more likely to have HCV genotype 3, bridging fibrosis/cirrhosis, higher HCV RNA levels, increased triglycerides and lower cholesterol levels. The only different body measurement was neck circumference which was greater in patients with steatosis and significantly decreased from baseline during the study. Hip circumference was predictive of steatosis at baseline.

CONCLUSIONS

Factors associated to the metabolic syndrome are important in co-infected patients. Treatment outcome affected steatosis in that viral eradication reduced steatosis in genotype 3 patients, but altogether steatosis did not affect efficacy of treatment in any genotype.

Clinical significance of metabolic syndrome in the setting of chronic hepatitis C virus infection

BACKGROUND & AIMS

The metabolic syndrome (MS) is a unique condition in which the underlying mechanism is related to insulin resistance. In hepatitis C virus (HCV) patients, insulin resistance has been linked to treatment failure. The aim of this study was to estimate the prevalence of MS in HCV patients undergoing antiviral therapy and to assess its predictive value in treatment outcome.

METHODS

All HCV treatment-naive patients who met the inclusion/exclusion criteria were studied (n = 228). MS was defined using the National Cholesterol Education Program Adult Treatment Panel III criteria. A logistic regression analysis was performed to study multivariable associations. The final model contained sex, ethnicity, body mass index, viral load, genotype, steatosis, fibrosis stage, and MS.

RESULTS

MS was present in 59 of 228 (26%) patients. Genotype 1 (P = .002) and presence of steatosis (P < .001) were found to be associated significantly with MS. Overall, sustained virologic response (SVR) was achieved in 108 of 228 (47%) patients. Male sex, non-Caucasian ethnicity, higher body mass index, high viral load, genotype 1, higher fibrosis stage, and MS were associated significantly with a lack of SVR. After adjusting for confounding variables, MS remained independently associated with a lack of SVR (P < .01). Specifically, subjects with MS were 3.8 (95% confidence interval, 1.4-10.5) times more likely to fail treatment than those without MS.

CONCLUSIONS

MS is seen frequently in patients with chronic HCV and is associated independently to lack of SVR. These findings support the concept that an aggressive intervention approach comprising lifestyle modification alone or in combination with drug treatment of the MS components may play an important role in improving antiviral responses in these patients.

Review article: nonalcoholic fatty liver disease and hepatitis C virus--partners in crime

BACKGROUND

Both nonalcoholic fatty liver disease (NAFLD) and chronic hepatitis C (CHC) are frequent causes of chronic liver disease. In recent years, there have been significant revelations as regards the relationship between NAFLD and CHC.

AIM

To conduct a systematic, evidence-based review of the epidemiology, pathophysiology and potential treatments of coexistent NAFLD and CHC.

METHODS

The terms such as hepatitis C, fatty liver, NAFLD, nonalcoholic steatohepatitis and steatosis were searched on PubMed up to January 2008. References from selected articles and pertinent abstracts were also included.

RESULTS

Hepatic steatosis affects up to 80% of patients with CHC and is dependent on both viral and host factors. While insulin resistance (IR) is associated with hepatic steatosis and hepatitis C virus, genotype-specific pathogenic mechanisms have been identified and are currently the focus of intense investigation in the literature. Clinical implications of concurrent NAFLD, CHC and IR include increased disease progression, elevated risk of hepatocellular carcinoma, and decreased response to antiviral therapy.

CONCLUSIONS

NAFLD and IR are common in patients with CHC virus infection. IR is a driving force in the development of hepatic steatosis. Because of the clinical implications of hepatic steatosis and IR in the setting of CHC, further studies evaluating treatments, which may increase response to antiviral therapy, are needed.

Insulin resistance impairs rapid virologic response in HIV/hepatitis C virus coinfected patients on peginterferon-alfa-2a

OBJECTIVES

To investigate the association between insulin resistance and rapid virologic response.

DESIGN

All consecutive HIV/hepatitis C virus coinfected patients who started peg-interferon alpha-2a (180 microg/week) and ribavirin 1000-1200 mg/day were analysed.

METHODS

Insulin resistance was defined according to the homeostasis model of assessment-insulin resistance calculated as fasting insulin (mIU/l) x fasting glucose (mmol/l)/22.5. Rapid virologic response was defined as testing negative for hepatitis C virus-RNA after 4 weeks of therapy. Fasting levels of insulin and glucose in plasma were measured in all patients on the first day of treatment. Hepatitis C virus-RNA was determined by quantitative PCR assay (version 3.0). Hepatitis C virus-RNA was measured by qualitative PCR assay (COBAS 2.0) after 4 weeks of treatment.

RESULTS

Seventy-four HIV/hepatitis C virus coinfected patients were enrolled [mean age 41.7 years (SD 5.3), 61 men, 54.1% with advanced fibrosis (F3-4 according to METAVIR classification), 52.4% with infection by hepatitis C virus genotype 1 or 4]. Rapid virologic response was reached by 30 subjects. In the multivariate analysis the independent predictors of rapid virologic response were: genotype 1 or 4 [adjusted odds ratio 0.18 (0.06-0.55)], hepatitis C virus-RNA < 400.000 UI/ml [adjusted odds ratio 0.229 (0.09-0.92)] and homeostasis model of assessment-insulin resistance more than 3.00 [adjusted odds ratio 0.1 (0.05-0.6)].

CONCLUSION

The homeostasis model of assessment-insulin resistance score should be evaluated and possibly corrected before starting anti-hepatitis C virus therapy.

Is serum uric acid a predictive factor of response to IFN-treatment in patients with chronic hepatitis C infection?

Several factors, including metabolic profile, are predictive of response to standard antiviral therapy in patients with chronic hepatitis C. In a retrospective study, it was investigated whether uric acid, involved in metabolic syndrome, could be included. A total of 153 patients (56.2% males; mean age 45.7 +/- 11.3 years) treated with pegylated-interferon and ribavirin were included. Eighty-five were infected with hepatitis C virus (HCV) genotype 1 or 4 and 68 with genotype 2 or 3. Viral load was >1,000,000 IU/ml in 101, < or =1,000,000 IU/ml in 35 and unknown in 17 patients. Ishak fibrosis score was < or =4 in 81, >4 in 15 and unknown in 57 patients. Mean serum uric acid was 5.05 +/- 1.3 mg/dl. Sustained virological response (negative serum HCV-RNA 6 months after treatment cessation) was achieved in 102 patients (67%). In the final logistic model, serum uric acid level > or =5.8 mg/dl (OR = 0.46; 95% CI: 0.30-0.62), viral load (OR = 0.29; 95% CI: 0.09-0.92) and HCV genotype (OR = 0.23; 95% CI: 0.09-0.60) were identified as the most important factors independently influencing clinical outcome. The prognostic role of serum uric acid was confirmed on the sub-sample reporting Ishak fibrosis score (OR = 0.49; 95% CI: 0.28-0.85). Serum uric acid level > or =5.8 mg/dl is predictive of poor response to HCV treatment. Prospective studies are needed to clarify the issue.

Interaction of metabolic syndrome, nonalcoholic fatty liver disease and chronic hepatitis C

Nonalcoholic fatty liver disease (NAFLD) has become one of the most prevalent liver diseases in the Western world. NAFLD represents a wide spectrum of histologic subgroups, with nonalcoholic steatohepatitis as the most aggressive form. The risk of developing NAFLD is strongly associated with metabolic syndrome and insulin resistance. The pathogenesis of NAFLD is a multiple-hit process resulting from hepatic fat deposition that is related to several conditions, including insulin resistance and central obesity. Additional hits, such as oxidative stress or adipocytokines produced by white adipose tissue, can further enhance liver damage leading to nonalcoholic steatohepatitis or fibrosis. Although NAFLD is often the primary liver disease of metabolic conditions, it can also exacerbate other liver diseases such as hepatitis C (HCV); indeed, more than 50% of patients with HCV have hepatic steatosis. Hepatic steatosis can be related to host factors (e.g., obesity, metabolic syndrome or insulin resistance) or to the genotype of virus (e.g., HCV genotype 3). Increasing evidence suggests that hepatic steatosis, insulin resistance and obesity in the setting of HCV have a negative impact on the efficacy of treatment and hepatic progression of fibrosis.

Prevalence of diabetes mellitus and insulin resistance in patients with chronic hepatitis C: comparison with hepatitis B virus-infected and hepatitis C virus-cleared patients

BACKGROUND/AIMS

Our aim was to evaluate the relationship between hepatitis C virus (HCV) infection and development of diabetes mellitus (DM) or insulin resistance (IR) in comparison with hepatitis B virus (HBV) infection and eradication of HCV infection by interferon treatment.

METHODS

This study consisted of 952 outpatients, including 544 HCV-infected (HCV+chronic), 286 HBV-infected (HBV+chronic) and 122 patients whose HCV was cleared by interferon treatment (HCV+cleared) (diabetes study). Among 849 without overt DM, IR was assessed in 423 patients, including 232 HCV-infected (HCV+chronic), 135 HBV-infected (HBV+chronic) and 56 HCV-eradicated patients (HCV+cleared) (IR substudy).

RESULTS

The prevalence of DM in the HBV+chronic, HCV+chronic and HCV+cleared groups was 6.3, 13.6 and 9.0%, respectively (HBV+chronic vs HCV+chronic, P<0.005), in the diabetes study, and the prevalence of IR in the HCV+chronic group (54.3%) was also higher than that in the HBV+chronic (36.3%) (P<0.005) and HCV+cleared groups (35.7%) (P<0.05) in the IR substudy. However, HCV infection was not shown to be independently associated with DM development [odds ratio (OR) 1.669; P=0.0936] and with IR (OR 1.531; P=0.2154) by multivariate analysis in comparison with HBV infection as control.

CONCLUSIONS

HCV-infected patients showed a higher prevalence of DM and IR than those with HBV infection. However, in Japan, other confounding factors appeared to be more important risk factors for the development of disturbance in glucose metabolism.

Insulin resistance in chronic hepatitis C: association with genotypes 1 and 4, serum HCV RNA level, and liver fibrosis

BACKGROUND & AIMS

Our study was designed to test the association between insulin resistance (IR) and hepatitis C virus (HCV) genotypes, serum HCV RNA level and liver fibrosis stage in a large prospective cohort of chronic hepatitis C (CHC) patients.

METHODS

Six hundred consecutive patients (CHC, n = 500; chronic hepatitis B (CHB), n = 100) were evaluated on the day of liver biopsy. IR (Homeostasis Model for Assessment of Insulin Resistance) and all components of the metabolic syndrome were assessed. By logistic regression, independent factors associated with IR and those associated with significant fibrosis were assessed in nondiabetic and noncirrhotic CHC, respectively. Parameters of IR were compared between hepatitis B and 240 CHC matched by epidemiologic, metabolic, and histologic features.

RESULTS

IR was present in 32.4% of the 462 nondiabetic CHC and associated with the metabolic syndrome, genotypes 1 and 4, significant fibrosis, and severe steatosis. IR was diagnosed in 15% of 145 CHC without metabolic syndrome or significant fibrosis, and associated with genotypes 1 and 4, high serum HCV RNA level, and moderate-severe necroinflammation. Significant fibrosis was present in 51.1% of the 454 noncirrhotic CHC patients and associated with male sex, age >40 years, IR, moderate-severe necroinflammation, and severe steatosis. IR was less frequent in CHB than in matched CHC (5% vs 35%, respectively, P < .001).

CONCLUSIONS

IR is a specific feature of CHC, associated with genotypes 1 and 4 and high serum HCV RNA level. Significant fibrosis is associated with IR independent from steatosis.

Altered expression of glucagon-like peptide-1 and dipeptidyl peptidase IV in patients with HCV-related glucose intolerance

BACKGROUND AND AIM

The pathogenesis of hepatitis C virus (HCV)-associated glucose intolerance remains unclear. Glucagon-like peptide-1 (GLP-1), a gut hormone, synthesizes hepatic glycogen and is inactivated by dipeptidyl peptidase IV (DPPIV). The aims of this study were to investigate the alterations in the expression of GLP-1 and DPPIV in HCV-associated glucose intolerance.

METHODS

We enrolled patients with HCV- or hepatitis B virus (HBV)-related liver disease (n = 94 and 37, respectively), patients with inflammatory bowel disease (IBD; n = 14) as disease controls, and healthy controls (n = 48). The serum or tissue GLP-1 and DPPIV expression levels were determined by enzyme immunoassay, immunoblotting, or immunostaining. The hepatic glycogen content was assayed by periodic acid-Schiff staining.

RESULTS

The serum GLP-1 levels were significantly decreased in the HCV group (4.9 +/- 0.3 ng/mL) than those in the controls (7.5 +/- 0.6 ng/mL), the HBV group (7.0 +/- 0.5 ng/mL), or the IBD group (10.8 +/- 1.0 ng/mL, P < 0.01). Although the ileum GLP-1 expression was not significantly different between the controls and the HCV group, the DPPIV expression was significantly increased in the ileum, liver, and serum in the HCV group. Hepatic glycogen content was decreased to a greater extent in the HCV group than that in the HBV group (127.5 +/- 5.3 vs 187.7 +/- 6.6 arbitrary units; n = 19, P < 0.01).

CONCLUSION

We demonstrated the altered expressions of GLP-1 and DPPIV in patients with HCV-associated glucose intolerance. Since hepatic glycogen synthesis, a GLP-1 action, was impaired, the altered expressions of GLP-1 and DPPIV may be involved in the development of HCV-associated glucose intolerance.

High hepatitis C viral load is associated with insulin resistance in patients with chronic hepatitis C

BACKGROUND AND AIMS

Although insulin resistance affects liver fibrosis progression and treatment response in chronic hepatitis C (CHC), the relationship between chronic hepatitis C virus (HCV) infection and insulin resistance (IR) remains to be firmly established. We thus studied the impact of host, metabolic and viral factors on IR in CHC patients.

METHODS

A total of 162 CHC patients with complete clinical data were enrolled. Among them, 94 received histological examinations. Quantitative HCV RNA was assayed by a real-time polymerase chain reaction (PCR) assay. Genotyping was performed by reverse transcription PCR with type-specific primers. The pretreatment IR index was determined using homeostasis model assessment (HOMA), and an index value of more than 2.4 was designated IR. Unadjusted and adjusted association of the HCV RNA level and IR was further analysed.

RESULTS

In multivariate linear regression analysis, a dose-response relationship was observed between the log(10) HCV RNA level and the presence of IR. IR was positively correlated with body mass index, triglyceride, HCV RNA and alanine aminotransferase levels, but negatively correlated with adiponectin level. Subgroup analysis stratified by HCV genotype showed that there was a trend towards a higher HOMR-IR index value and lower adiponectin levels in genotype 1 patients. Histological analysis showed that IR was positively associated with the severity of hepatic steatosis.

CONCLUSIONS

Our data indicate that higher HCV RNA levels are associated with the presence of IR in CHC patients. Further studies are needed to clarify the interplays between HCV infection, IR and adiponectin in an attempt to develop new adjuvant therapy for CHC.

Insulin resistance and response to therapy in patients infected with chronic hepatitis C virus genotypes 2 and 3

BACKGROUND/AIMS

Obesity is associated with impaired treatment responses in chronic hepatitis C. The aim of this study was to determine the relationship between the insulin resistance frequently seen in obese subjects and sustained virological response to anti-viral therapy (SVR) in patients with genotype 2 or 3 infection.

METHODS

Eighty-two patients were studied; 59 received interferon/ribavirin while 23 received peg-interferon/ribavirin.

RESULTS

The overall SVR was (77%). Patients with a SVR had lower mean serum insulin (10.7+/-0.8 microU/ml vs. 22.2+/-4.9; P = 0.03), fibrosis stage (1.9+/-0.1 vs. 2.7+/-0.3; P = 0.007) and insulin resistance measured by the homeostasis model (HOMA-IR) (2.5+/-0.2 vs. 6.1+/-1.5; P = 0.03). Age, gender, ethnicity, alcohol consumption, treatment regimen, viral load, portal activity and steatosis did not influence the SVR. By linear regression, body mass index (P < 0.001) and fibrosis stage (P < 0.001) were independently associated with HOMA-IR. After adjusting for fibrosis stage, patients with HOMA-IR of < 2 were 6.5 times more likely to achieve SVR than those with HOMA-IR > or = 2.

CONCLUSIONS

Even in treatment-responsive genotypes 2 and 3, high HOMA-IR is associated with a reduced response. Improving insulin sensitivity may be a useful adjunct to anti-viral therapy in these individuals.

High incidence of type 1 diabetes mellitus during or shortly after treatment with pegylated interferon alpha for chronic hepatitis C virus infection

BACKGROUND

Development of diabetes mellitus (DM) during or shortly after treatment with interferon alpha (IFN-alpha) in patients with chronic hepatitis C virus (HCV) infection has been reported sporadically. We prospectively screened for DM during and after IFN-alpha therapy for chronic HCV infection.

METHODS

Blood glucose levels of patients with chronic HCV infection were routinely assessed at all outpatient visits during and after treatment with pegylated-IFN-alpha (Peg-IFN-alpha) and ribavirin (Riba).

RESULTS

Between December 2002 and October 2005, 189 non-diabetic patients were treated with Peg-IFN-alpha/Riba, of whom five developed type 1 DM (2.6%), three type 2 DM (1.6%) and one an indeterminate type of DM. Classical symptoms of DM were present in three patients who developed DM shortly after cessation of Peg-IFN-alpha/Riba. In the other patients, symptoms of DM were either indistinguishable from side effects caused by Peg-IFN-alpha/Riba or absent.

CONCLUSION

Our study showed a high incidence of type 1 DM during Peg-IFN-alpha/Riba therapy for chronic HCV infection. Symptoms of DM may be absent or mistaken for Peg-IFN-alpha/Riba-associated side effects. To diagnose DM without delay, we propose routine assessment of blood glucose at all outpatient visits during and after Peg-IFN-alpha/Riba treatment in chronic HCV patients.

Identification of liver fibrosis in HIV/HCV-coinfected patients using a simple predictive model based on routine laboratory data

We constructed noninvasive models to predict significant fibrosis (F > or = 2) and advanced fibrosis (F > or = 3) among human immunodeficiency virus (HIV)/hepatitis C virus (HCV)-coinfected patients, naïve for anti-HCV treatment. A total of 296 patients with liver biopsy were randomly assigned to an estimation group (EG = 226; 70%) and a validation group (VG = 70; 30%). We developed the Hospital Gregorio Marañón (HGM)-1 index, based on platelet count, aspartate aminotransferase (AST) and glucose, to predict F > or = 2 and the HGM-2 index, based on platelet count, international normalized ratio, alkaline phosphatase and AST to predict F > or = 3. The area under the receiver operating characteristic curves (AUROCs) of the HGM-1 index for the EG and the VG were 0.807 and 0.712 respectively. The AUROCs of the HGM-2 index for the EG and the VG were 0.844 and 0.815 respectively. With the HGM-1 index applied to the VG, using best cutoff scores, the negative predictive value (NPV) to exclude F > or = 2 was 54.5% and the positive predictive value (PPV) to confirm F > or = 2 was 93.3%. With the HGM-2 index applied to the VG, using best cutoff scores, the NPV to exclude F > or = 3 was 92.3, and the PPV to confirm F > or = 3 was 64.3%. Thus, HGM-2 accurately predicted F > or = 3 among HIV/HCV-coinfected patients. HGM-1 was less accurate at predicting F > or = 2.

Management of HIV/hepatitis C virus-coinfected patient non-responders to hepatitis C virus antiviral therapy and relapsers

PURPOSE OF REVIEW

To examine recent developments in the management of HIV/hepatitis C virus-coinfected patients who relapsed or who responded poorly to initial therapy, with particular emphasis on peginterferon plus ribavirin.

RECENT FINDINGS

End-stage liver disease is the first cause of non-AIDS-related mortality in patients on antiretroviral therapy. A pool analysis of recent studies suggested that only 33% of HIV/hepatitis C virus-coinfected patients will achieve sustained virological response with peginterferon plus ribavirin. A substudy of the APRICOT trial shows that this strategy will benefit liver histology even in non-responding patients. The management of side effects is important and, according to a recent study, erythropoietin can improve clinical outcomes of hepatitis C virus therapy, although no direct association between response and the control of haematological toxicity was demonstrated. Patients who did not clear hepatitis C virus RNA with a slow virological response to previous courses of peginterferon and ribavirin might benefit from prolonging therapy to up to 72 weeks.

SUMMARY

Re-treatment strategies in non-responders to previous interferon-based therapies and relapsers should consider the previous virological response profile and ensure that treatment-related toxicity is controlled to avoid dose reductions or premature treatment interruptions. Further studies are needed to optimize therapeutic regimens.

Management and therapy of chronic hepatitis C in HIV

PURPOSE OF REVIEW

Chronic hepatitis C is currently one of the leading causes of hospitalization and death in HIV+ persons. Treatment is particularly challenging in coinfected patients due to lower efficacy and more side effects.

RECENT FINDINGS

The combination of pegylated interferon plus ribavirin is the current treatment of choice. In the absence of contraindications, treatment should be provided with no restrictions up front (e.g., asking unnecessarily for a liver biopsy) and revisited at weeks 4 and 12. Treatment should only be continued in early virological responders. The use of standard ribavirin doses (1000-1200 mg/day) and for at least 12 months is crucial to maximize the effect of therapy. In patients with rapid virological response (undetectable viraemia at week 4), shorter periods of therapy (24 weeks) may be advisable for hepatitis C virus genotypes 2 and 3. Patients with low CD4 percentages should defer treatment and prioritize highly active antiretroviral therapy. Didanosine should never be co-administered with ribavirin due to potential life-threatening complications. When possible, zidovudine, stavudine and abacavir should be replaced by other agents having no deleterious interactions with ribavirin.

SUMMARY

The treatment of chronic hepatitis C has become a priority in hepatitis C virus/HIV-coinfected patients, and the best results are obtained by tailoring therapy to the individual patient's characteristics.

Hepatic iron accumulation may be associated with insulin resistance in patients with chronic hepatitis C

BACKGROUND/AIM

Insulin resistance and hepatic iron overload are frequently demonstrated in hepatitis C virus (HCV)-related liver diseases. We investigated the relationship between insulin resistance and hepatic iron deposition in patients with chronic HCV infection.

METHODS

Insulin resistance was evaluated using the homeostasis model assessments for insulin resistance (HOMA-IR) in 56 non-diabetic non-obese patients with biopsy proven chronic hepatitis C. The relationship between insulin resistance and serum ferritin levels or the grade of hepatic iron deposition was assessed.

RESULTS

The levels of plasma immunoreactive insulin (IRI) and HOMA-IR were significantly correlated with serum ferritin levels and the grade of hepatic iron deposition (P = 0.003).Although IRI and HOMA-IR increased in parallel with the development of hepatic fibrosis, insulin resistance (HOMA-IR > 2) was observed in 11 (26.2%) of 42 patients even without severe fibrosis (F0-2). Among patients without severe fibrosis, IRI and HOMA-IR were significantly higher in patients with iron deposits than in those without iron deposits.

CONCLUSION

Hepatic iron overload may be associated with insulin resistance in patients with chronic hepatitis C, especially in patients with mild to moderate fibrosis.

Antiviral therapy: chronic hepatitis C

The combination of pegylated interferon (IFN) with ribavirin is the standard of care for chronic hepatitis C. Response rates range from 50 to 90% for genotype 1 and 2/3 which also differ in the duration of treatment (48 vs 24 weeks, respectively). Therapy if given with weight-based dosing may be shortened from 24 to 12, 14 or 16 weeks (genotypes 2 and 3), and from 48 to 24 weeks (genotype 1) in case of hepatitis C virus (HCV) clearance at week 4, without reducing sustained virologic response (SVR). Conversely, prolonging treatment for 72 weeks in those with only a decrease of viral load at week 4, i.e. "slow responders" increases SVR rates by preventing relapse. In spite of such progress, over half of patients are relapsers or nonresponders. If the previous treatment was suboptimal, retreatment with higher doses or longer duration may be beneficial unless an individual was a 'null responder' previously. New promising anti-HCV molecules (antiproteases and antipolymerases), some with potent antiviral activity, are in phase II trials but appear to require the addition of IFN and ribavirin to maintain viral suppression. Other immunomodulatory agents such as new IFN or therapeutic vaccines and alternatives to ribavirin are also under development. Future regimens should improve efficacy and provide shorter and better-tolerated combination therapy.

Retreatment of chronic hepatitis C in previous non-responders and relapsers

Therapy for chronic hepatitis C has improved dramatically over the past 20 years. Unfortunately, approximately 50% of those treated do not have a durable response to therapy. Non-responders and relapsers after previous interferon-based therapy are particularly challenging with regard to clinical management. This article provides a general overview of the treatment of hepatitis C and reviews present data regarding management of patients with chronic hepatitis C who are non-responders or relapsers after previous treatment. The review ends with the authors' opinion regarding present management of non-responders and relapsers and future emerging therapies.

Glucose abnormalities are an independent risk factor for nonresponse to antiviral treatment in chronic hepatitis C

OBJECTIVES

The influence of glucose abnormalities on the efficacy of antiviral treatment is unknown. This study investigated whether glucose abnormalities (impaired fasting glucose and type 2 diabetes) influence the response to antiviral therapy with interferon plus ribavirin in patients with chronic hepatitis C.

METHODS

A total of 178 treatment-naïve patients with chronic hepatitis C treated with combination therapy were retrospectively studied. SVR was assessed after completing treatment. Fasting plasmatic glucose was measured prior to therapy.

RESULTS

Compared with nonresponders (N = 111), patients with SVR (N = 67) had lower plasma glucose (94.1 +/- 12.7 vs 104.4 +/- 25.8 mg/dL, P= 0.001) and a lower prevalence of glucose abnormalities (24.24%vs 44.14%, P= 0.012). The SVR rate was 45.13% in patients with normoglycemia (N = 113), 28.26% in patients with impaired fasting glucose (N = 46), and 15.78% in type 2 diabetic patients (N = 19) (P < 0.001). Multivariate logistic regression identified genotype 1 (OR 1.55, 95% CI 1.01-2.41, P= 0.05), gamma-glutamyltranspeptidase level (OR 6.41, 95% CI 1.86-22.07, P= 0.003), and presence of glucose abnormalities (OR 2.33, 95% CI 1.04-5.20, P= 0.039) as being independently associated with the absence of an SVR. In addition, patients with glucose abnormalities (N = 65) showed a lower virological response rate when compared with a subgroup of normoglycemic patients (N = 65) matched for sex, age, and liver fibrosis (24.6%vs 44.6%, P= 0.001).

CONCLUSIONS

Glucose abnormalities are an independent predictor of poor virological response to combined therapy in hepatitis C virus infected patients.

Increased serum gamma-glutamyl-transpeptidase concentration is associated with nonalcoholic steatosis and not with cholestasis in patients with chronic hepatitis C

BACKGROUND AND AIM

Increased pretreatment gamma-glutamyl-transpeptidase (gammaGT) is common in patients with chronic hepatitis C and with little or no alcohol consumption. The mechanism involved in this phenomenon is unclear, and the aim of this study was to investigate factors associated with increased gammaGT levels, specifically looking at the role of cholestasis that frequently accompanies hepatitis C.

METHODS

Fifty patients with chronic hepatitis C enrolled in two trials of antiviral treatment, 25 with normal and 25 with elevated pretreatment gammaGT levels, were retrospectively selected. In addition to the common liver function and virological tests, other values measured were serum bile acid concentration and composition by gas-chromatography as a sensitive index of cholestasis, and liver biopsy scores for cholestasis and steatosis in addition to siderosis, fibrosis and inflammation.

RESULTS

Total mean serum bile acid concentration was 11.6 +/- 1.4 micromol/L and 8.5 +/- 1.2 micromol/L (not significant) in patients with elevated and with normal gammaGT, respectively, and individual bile acid composition was similar in the two groups. By univariate analysis, serum gammaGT level was linearly related to total serum bile acid (P < 0.05) and to cholestasis score (P < 0.001) among other variables, but steatosis score (P < 0.001) and Knodell score (P < 0.04) were the only variables independently associated with elevated serum gammaGT level by multivariate analysis.

CONCLUSIONS

Increased serum gammaGT level in patients with chronic hepatitis C is associated with liver steatosis and fibrosis, and indicates more advanced liver disease rather than reflecting the cholestasis that often accompanies this condition.

Suppressor of cytokine signaling 3 (SOCS3) expression and hepatitis C virus-related chronic hepatitis: Insulin resistance and response to antiviral therapy

The response to antiviral therapy is lower in hepatitis C virus (HCV) patients with genotype 1 than in those with genotype 2. Overexpression of the suppressor of cytokine signaling 3 (SOCS3) gene in liver tissue is associated with a poorer treatment outcome in patients with chronic hepatitis C viral genotype 1. Also, insulin resistance has been implicated in nonresponse to an anti-HCV treatment. To understand why HCV genotype 1 patients respond differently, we investigated SOCS3 gene expression, metabolic syndrome (MS), and the response to therapy in a cohort of patients with HCV-related hepatitis. A total of 198 patients (108 with genotype 1 and 90 with genotype 2) treated with pegylated interferon plus ribavirin were consecutively enrolled in the study. We measured SOCS3 expression in Epstein-Barr virus-transformed lymphoblastoid cell lines derived from peripheral lymphocytes of a subset of 130 patients. MS was more frequent in genotype 1 patients than in genotype 2 patients (P < 0.01). Nonresponders (P < 0.01), MS (P < 0.001), and genotype 1 (P < 0.001) were significantly related to SOCS3 overexpression. However, SOCS3 levels were higher in nonresponders also, regardless of the genotype (P < 0.01). In a univariate analysis, the genotype (P < 0.001), age (P < 0.001), SOCS3 (P < 0.001), and MS (P < 0.001) were significantly related to the response to therapy. However, in a multivariate analysis, SOCS3 was the only independent predictor of the response (odds ratio = 6.7; P < 0.005).

CONCLUSION

We speculate that SOCS3 expression per se may influence the response to antiviral therapy and that the genotype 1b virus might induce its up-regulation. This may account for the different responses to therapy between genotype 1-infected and genotype 2-infected patients.

Hepatitis C and steatosis

Hepatitis C infection and non-alcohol-related hepatic steatosis are the most common liver diseases worldwide, and both conditions often co-exist in the same patient. Hepatitis C virus (HCV) genotype 3 directly induces development of steatosis, whereas in patients with non-genotype 3 chronic hepatitis C infection, insulin resistance plays a key role in the pathophysiology of steatosis. Insulin resistance and its clinical components including obesity, hyperglycemia, hypertriglyceridemia, increased blood pressure, and low HDL-cholesterol levels are often seen in patients with chronic hepatitis C infection. Both increased adipocity and presence of steatosis may increase the risk of fibrosis progression, and both have been associated with a decreased rate of response to antiviral treatment. Hence, liver steatosis in the setting of HCV infection is a distinct condition with specific clinical and prognostic implications. Accumulating evidence suggests that weight management may lead not only to a decrease in steatosis but also improvement in fibrosis severity. However, further studies are necessary to determine whether weight reduction improves response to antiviral therapy.

Prediction of response to pegylated interferon and ribavirin in hepatitis C by polymorphisms in the viral core protein and very early dynamics of viremia

OBJECTIVE

To evaluate power of amino acid polymorphisms in core protein of hepatitis C virus (HCV) for predicting sustained virological response (SVR) to pegylated interferon (Peg-IFN)/ribavirin, when they were combined with virological response.

METHODS

Peg-IFN/ribavirin was given to 118 patients infected with HCV genotype 1b in high viral loads. Amino acid polymorphisms (Arg70 vs. Gln70 and Leu91 vs. Met91) in combination with on-treatment virological responses were correlated with SVR.

RESULTS

End-of-treatment response (ETR) was achieved in 71% and SVR in 47% of the 118 patients. In multivariate analysis, Arg70 and Leu91, and higher ribavirin dose were independently associated with ETR. In patients with Gln70 and/or Met91, SVR was more frequent in those with than without prompt virological response (PVR) for a decrease in viral load >or=1.0 log by 48 h. Specificity in predicting patients without ETR and SVR, in combination with core polymorphisms, was not different between PVR and early virological response at 12 weeks.

CONCLUSION

Core polymorphisms combined with PVR would be useful in promptly identifying the patients who will not respond to Peg-IFN/ribavirin, thereby avoiding unrewarding side effects and high costs.

Predictors of response of US veterans to treatment for the hepatitis C virus

The currently recommended treatment for hepatitis C virus (HCV) infection is pegylated interferon alfa (PEG-INF) and ribavirin, which can be difficult to tolerate. More information about predicting sustained virologic response (SVR) may allow more informed treatment decisions to be made. This retrospective observational cohort study identified predictors of SVR to PEG-INF and ribavirin in routine medical practice at 121 Department of Veterans Affairs facilities. Among 5,944 patients infected with HCV genotypes 1, 2, or 3 who had been treated with PEG-INF and ribavirin, SVR rates were 20%, 52%, and 43%, respectively, and discontinuation rates were 68% (prior to 48 weeks), 34% (24 weeks), and 41% (24 weeks), respectively. In multivariate analysis, significant predictors of decreased likelihood of genotype 1 patients having an SVR were being African American, clinical liver disease, diabetes, low cholesterol, low hemoglobin, low platelet count, and treatment at a low-volume facility. Predictors of increased likelihood of genotype 1 patients having an SVR were low-level HCV viremia, elevated ALT quotient, and receiving PEG-INF 2A (rather than 2B). For genotype 2 patients, increasing body mass index, prior use of interferon, and low platelet count were negative predictors; only low-level HCV viremia was a positive predictor. For genotype 3 patients, only receiving PEG-INF 2A affected the likelihood of an SVR; its effect was positive.

CONCLUSION

Among patients for whom HCV treatment is initiated during routine medical care, multiple factors including form of PEG-INF received affect the SVR rate for genotype 1 patients. Few of these factors affect the rate for genotype 2 patients, and even fewer do so for genotype 3 patients.

Insulin resistance and liver injury in hepatitis C is not associated with virus-specific changes in adipocytokines

The role of tumor necrosis factor alpha, interleukin 6, leptin, and adiponectin in the pathogenesis of hepatitis C virus (HCV)-associated insulin resistance (IR) remains controversial. We tested the hypothesis that these adipocytokines contribute to chronic HCV-associated IR and liver injury by first comparing their serum levels and homeostasis model assessment of insulin resistance (HOMA-IR) in 154 untreated, non-diabetic, HCV-infected male subjects with fibrosis stage 0-2, to that in 75 healthy volunteers matched for age, body mass index (BMI), and waist-hip ratio (WHR). We next examined whether the adipocytokine levels were associated with the extent of hepatic steatosis, portal/periportal inflammation and fibrosis in our total cohort of 240 HCV-infected male subjects. Significantly higher levels of HOMA-IR (2.12 versus 1.63, P = 0.01), TNFalpha (1.28 versus 0.60 pg/ml, P < 0.001) and IL6 (2.42 versus 1.15 pg/ml, P = 0.001) were noted in the HCV cohort compared with healthy controls respectively, but there were no significant differences in leptin and adiponectin concentrations. By multiple linear regression, independent predictors of HOMA-IR included the body mass index, and the serum levels of leptin (positive correlation) and adiponectin (negative correlation), but not that of TNFalpha and IL6. Only TNFalpha levels were correlated with the extent of histological injury (portal/periportal inflammation, P = 0.02).

CONCLUSION

Whereas leptin and adiponectin contribute to IR, none of the adipocytokines accounted for the elevated IR in HCV-infected subjects. The adipocytokines were not associated with histological features of chronic HCV infection except for TNFalpha which correlated with portal/periportal inflammation. HCV-associated IR is most likely an adipocytokine-independent effect of the virus to modulate insulin sensitivity.

An assessment of serum leptin levels in patients with chronic viral hepatitis: a prospective study

BACKGROUND

The role of leptin in the course of liver disease due to chronic viral hepatitis (CVH) remains controversial. Our aims were to investigate the relationship between serum leptin concentrations and the severity of liver disease in a cohort of subjects with HBeAg negative chronic hepatitis B (CHB) and C (CHC) and to analyze the effect of body composition, the leptin system and insulin resistance together with viral factors on virologic response to antiviral treatment.

METHODS

We studied 50 (36 men) consecutive patients suffering from biopsy-proven CVH due to HBV (n = 25) or HCV (n = 25) infection. Thirty-two (17 men) healthy volunteers served as controls. Levels of serum leptin and insulin were determined by immunoassays at baseline and at the end of the treatment.

RESULTS

A significant association between serum leptin levels and the stage of hepatic fibrosis was noted; patients with cirrhosis presented higher serum leptin levels compared to those with lower fibrosis stage [CHB patients (17436 pg/ml vs 6028.5 pg/ml, p = 0.03), CHC patients (18014 pg/ml vs 4385 pg/ml, p = 0.05]. An inverse correlation between lower leptin levels and response to lamivudine monotherapy was noted in patients with CHB; those with a virologic response presented lower serum leptin levels (5334 vs 13111.5 pg/ml; p-value = 0.003) than non-responders. In genotype 1 CHC patients, insulin resistance played a significant role in the response to antiviral therapy.

CONCLUSION

Our data clearly suggest that cirrhosis due to CHB or CHC is associated with higher leptin levels. Increased serum leptin levels represent a negative prognostic factor for response to lamivudine monotherapy in patients with CHB. In CHC patients insulin resistance strongly influences the response to antiviral treatment in patients infected with genotype 1.