Race, insulin resistance and hepatic steatosis in chronic hepatitis C

Predictors of virological response to a combination therapy with pegylated interferon plus ribavirin including virus and host factors

A combination therapy with pegylated interferon (PEG-IFN) plus ribavirin (RBV) has made it possible to achieve a sustained virological response (SVR) of 50% in refractory cases with genotype 1b and high levels of plasma HCVRNA. Several factors including virus mutation and host factors such as age, gender, fibrosis of the liver, lipid metabolism, innate immunity, and single nucleotide polymorphism (SNPs) are reported to be correlated to therapeutic effects. However, it is difficult to determine which factor is the most important predictor for an individual patient. Data mining analysis is useful for combining all these together to predict the therapeutic effects. It is important to analyze blood tests and to predict therapeutic effects prior to initiating treatment. Since new anti-HCV agents are under development, it will be necessary in the future to select the patients who have a high possibility of achieving SVR if treatment is performed with standard regimen.

Associations between serum lipids and hepatitis C antiviral treatment efficacy

Approximately one half of patients who undergo antiviral therapy for chronic hepatitis C virus (HCV) genotype 1 infection do not respond to treatment. African Americans (AAs) are less responsive to treatment than Caucasian Americans (CAs), but the reasons for this disparity are largely unknown. Recent studies suggest that serum lipids may be associated with treatment response. The aims of this study were to evaluate baseline and changes in serum lipids during therapy, determine whether serum lipids are associated with virological response, and assess whether these measures explain the racial difference in efficacy. The study participants were from Virahep-C, a prospective study of treatment-naïve patients with genotype 1 HCV infection who received peginterferon (PEG-IN) alfa-2a plus ribavirin therapy for up to 48 weeks. Fasting serum lipids were analyzed at baseline and during and after therapy in 160 AAs and 170 CAs. A relative risk (RR) model was employed to evaluate characteristics associated with sustained virological response (SVR). Antiviral therapy was associated with changes in serum lipids during and after antiviral therapy, with the changes differing by race and the amount of PEG-IFN taken. Baseline lipid measures independently associated with higher rates of SVR were lower triglyceride and higher low-density lipoprotein cholesterol, with an interaction between high-density lipoprotein cholesterol (HDLc) and gender. Lipid measures did not contribute significantly to an explanation of the racial difference in SVR.

CONCLUSION

Serum lipids are associated with SVR, although these paramaters did not explain the racial difference in treatment response. The results of this study are compatible with proposed biological mechanisms of HCV entry, replication, and secretion, and may underscore new potential therapeutic targets for HCV eradication.

Metabolic disorders associated with chronic hepatitis C: impact of genotype and ethnicity

BACKGROUND & AIM

Patients with hepatitis C virus (HCV) infection, especially those with genotypes 1 and 4, have an increased risk of developing metabolic disorders. The aim of this study was to evaluate the associations among metabolic disorders, ethnicity and genotype in a large cohort of patients with chronic hepatitis C (CHC).

PATIENTS AND METHODS

All consecutive patients with CHC who were seen in our hepato-gastroenterology unit between January 2002 and September 2008 were included. Demographical data and variables related to the metabolic syndrome were collected. Insulin resistance was assessed using the homeostasis model for the assessment of insulin resistance test (HOMA-IR) test.

RESULTS

Among the 454 CHC patients, the prevalence of the metabolic syndrome was 12.4%. The HOMA-IR test was performed in 140 patients, and 35.0% had insulin resistance. There were more Black Africans among the patients with genotypes 1/4 than among those with genotypes 2/3 (32.0 vs 1.2%, P<0.0001). Insulin resistance was more common in patients with genotypes 1/4 than in those with genotypes 2/3 (17 vs 1.7%, P=0.0001 and 43.3 vs 16.3%, P=0.001, respectively). Genotypes 1/4 were more frequently present in patients with insulin resistance than in those without insulin resistance (85.7 vs 60.5%, P=0.001). By logistic regression, genotypes 1/4 [odds ratio (OR)=2.79; 95% confidence interval (CI): 1.09-7.12, P=0.032] and older age (OR=1.03; 95% CI: 1.004-1.06, P=0.024) were independently associated with the presence of insulin resistance.

CONCLUSIONS

In CHC, insulin resistance is independently associated with the presence of genotypes 1/4. Ethnicity is not independently associated with metabolic disorders in patients with CHC.

Superior response to pegylated interferon and ribavirin in Asians with chronic hepatitis C

PURPOSE

Reported sustained virological response (SVR) rates in Asians with chronic hepatitis C (CHC) exceed those of other ethnic groups, but differences in body weight across races potentially confound this observed superior response. Our aim was to determine whether Asian race independently predicts SVR within a multicultural clinic setting.

METHODS

Patients with genotype 1, 2 and 3 CHC prescribed peginterferon and weight-based ribavirin were included in this retrospective study. Logistic regression was performed to identify factors associated with SVR.

RESULTS

Three-hundred ninety-two patients (BMI 26.9 ± 5.0 kg/m(2), genotype 1 66%, viral load 5.9 ± 0.66 log(10) IU/ml, advanced fibrosis 53%) were included in this study. Caucasians comprised 81%, South Asians 9% and Asians (Non-South) 10%. SVR was achieved by 54% overall, but was highest amongst Asians (Non-South) (79%) compared with South Asians (56%, P = 0.04) and Caucasians (50%, P < 0.001) despite a predominance of genotype 3 infection amongst the South Asians. Asians (Non-South) had the highest SVR rate even amongst those infected with genotype 1 (75%) and those with advanced fibrosis (77%). Independent of viral genotype, Asian (Non-South) race was a strong predictor of SVR (OR 5.10 vs. Caucasians, 95% CI 1.72-17.71, OR 7.84 vs. South Asians, 95% CI 1.62-37.84), as were treatment naïve status (OR 3.85, 95% CI 1.76-8.89), non-diabetic status (OR 3.70, 95% CI 1.30-11.11), non-obesity (OR 2.13, 95% CI 1.06-4.35), peginterferon α2a (2.08 vs. α2b, 95% CI 1.16-3.85), steatosis <10% (OR 2.0, 95% CI 1.05-3.85) and ribavirin exposure (mg/kg/day) (OR 1.13, 95% CI 1.01-1.28).

CONCLUSION

Asian (Non-South) race is a strong independent predictor of SVR.

Nonalcoholic fatty liver disease/nonalcoholic steatohepatitis: histological diagnostic criteria and scoring systems

Nonalcoholic fatty liver disease (NAFLD) is recognized as the most common cause of chronic liver disease in western countries. NAFLD is etiologically associated with systemic and hepatic insulin resistance and is considered by many as the hepatic manifestation of the metabolic syndrome. NAFLD has a wide histological spectrum ranging from 'simple' steatosis to nonalcoholic steatohepatitis (NASH), which may progress to cirrhosis. Hepatocellular carcinoma may occur in NASH-related cirrhosis. The diagnosis of NAFLD/NASH is based on clinico-pathological criteria. Currently available noninvasive tests for the diagnosis of NASH lack specificity and sensitivity, so liver biopsy, despite its limitations, still remains the 'golden standard' for confirming or excluding NASH in a patient with chronically-elevated liver enzymes and image-detected steatosis. This review examines the currently used criteria for the histopathological diagnosis of NAFLD/NASH in adults and children and the relevant histological scoring systems.

Hepatitis C and hepatic steatosis

Hepatic steatosis is commonly seen in patients with chronic hepatitis C infection, and the two together have a greater association than by chance alone. Hepatitis C virus is closely associated with lipid metabolism throughout its lifecycle. Hepatic steatosis is more common in genotype 3 infection, due to direct viral effects including through microsomal triglyceride transfer protein, peroxisome proliferator activating receptor, and sterol regulatory element binding protein. In non-genotype 3 infection, hepatic steatosis is considered largely to be due to alterations in host metabolism, particularly through insulin resistance. The clinical relevance of this association has yet to be fully explored. Hepatic steatosis is associated with increased hepatic fibrosis and a reduced level of sustained virological response to pegylated interferon and ribavirin. Small studies trialing adjuvant anti-diabetic therapies or HMG-CoA reductase inhibitors with pegylated-interferon and ribavirin have shown an improved sustained virological response and reduced viral titer. Furthermore, simple lifestyle alterations showed positive effects on parameters of disease activity. These insights raise the possibility of novel treatment options.

Management of nonresponsive hepatitis C

More than 50% of hepatitis C virus (HCV)-infected patients do not respond to the classical pegylated interferon (PEG-IFN)/ribavirin combination therapy. However, failing to respond to one course of treatment is not synonymous of therapy failure and retreatment is often beneficial. Alternative retreatment strategies include repeating the classical standard of care with an optimized drug regimen and adherence, including ribavirin serum concentration adjustment, correcting, if at all possible, comorbidities, and the addition of new specific anti-HCV molecules to the backbone of pegylated interferon/ribavirin. Options of retreatment should include consensus and natural interferons. For patients with advanced disease exposed to a high risk of lethal complications, customized maintenance therapy could be an effective option since it may slow down complications in some patients. Since low-dose interferon monotherapy is not sufficient, such a maintenance therapy remains to be verified via clinical trials. New possibilities of noninvasive assessment of fibrosis and the use of genetic tests to predict fibrosis progression and responsiveness to interferon are major emerging opportunities that run parallel to the revolution of the pharmacologic armentarium.

Impact of amino acid substitutions in the hepatitis C virus genotype 1b core region on liver steatosis and hepatic oxidative stress in patients with chronic hepatitis C

BACKGROUND

Liver steatosis and hepatic oxidative stress are the histopathological features of chronic hepatitis C. Hepatitis C virus (HCV) genotype 1 core protein induces hepatic steatosis and reactive oxygen species production in transgenic mice. The amino acid substitutions in the HCV core region appear to be related to hepatocarcinogenesis.

AIMS

The aim of this study was to clarify the impact of mutations in the HCV core region on oxidative stress and lipid metabolism in patients with chronic hepatitis C.

METHODS

Sixty-seven patients (35 men, 32 women; mean age, 58.4 +/- 10.2 years) with chronic hepatitis C with high titres (>5 log IU/ml) were enrolled. Substitutions in amino acids 70, 75 and 91 of the HCV genotype 1b core region, the percentage of hepatic steatosis, and hepatic 8-hydroxy-2'-deoxyguanosine (8-OHdG) levels were investigated in all patients. Urinary 8-OHdG levels were measured in 35 patients.

RESULTS

Body mass index, alanine aminotransferase, gamma-glutamyl transferase, and triglyceride levels and substitutions of amino acid 70/Q (glutamine) were significantly associated with the presence of steatosis on univariate analysis. Multivariate analysis showed that substitution of amino acid 70 of glutamine and triglyceride levels were the independent factors related to liver steatosis. Hepatic and urinary 8-OHdG levels were significantly higher in patients with methionine at amino acid 91 of the HCV core region than in those with leucine.

CONCLUSION

Substitutions in the amino acids of the HCV genotype1b core region are associated with hepatic steatosis and oxidative stress in patients with chronic hepatitis C.

Practice guidelines for the diagnosis and management of nonalcoholic fatty liver disease. A decalogue from the Italian Association for the Study of the Liver (AISF) Expert Committee

We report the evidence-based Italian Association for the Study of Liver guidelines for the appropriate diagnosis and management of patients with nonalcoholic fatty liver disease in clinical practice and its related research agenda. The prevalence of nonalcoholic fatty liver disease varies according to age, gender and ethnicity. In the general population, the prevalence of nonalcoholic fatty liver disease is about 25% and the incidence is of two new cases/100 people/year. 2-3% of individuals in the general population will suffer from nonalcoholic steatohepatitis. Uncomplicated steatosis will usually follow a benign course. Individuals with nonalcoholic steatohepatitis, however, have a reduced life expectancy, mainly owing to vascular diseases and liver-related causes. Moreover, steatosis has deleterious effects on the natural history of HCV infection. Nonalcoholic fatty liver disease is usually diagnosed in asymptomatic patients prompted by the occasional discovery of increased liver enzymes and/or of ultrasonographic steatosis. Medical history, complete physical examination, etiologic screening of liver injury, liver biochemistry tests, serum lipids and insulin sensitivity tests should be performed in every patient. Occult alcohol abuse should be ruled out. Ultrasonography is the first-line imaging technique. Liver biopsy, the gold standard in diagnosis and prognosis of nonalcoholic fatty liver disease, is an invasive procedure and its results will not influence treatment in most cases but will provide prognostic information. Assessment of fibrosis by composite scores, specific laboratory parameters and transient elastography might reduce the number of nonalcoholic fatty liver disease patients requiring liver biopsy. Dieting and physical training reinforced by behavioural therapy are associated with improved nonalcoholic fatty liver disease. Diabetes and the metabolic syndrome should be ruled out at timed intervals in nonalcoholic fatty liver disease. Nonalcoholic steatohepatitis patients should undergo periodic evaluation of cardiovascular risk and of advancement of their liver disease; those with nonalcoholic steatohepatitis-cirrhosis should be evaluated for early diagnosis of hepatocellular carcinoma.

[Hepatitis C and metabolic syndrome]

Insulin resistance is a predictive factor of response to treatment with peginterferon and ribavirin in patients with hepatitis C. Insulin resistance impairs sensitivity to interferon and can block its intracellular signalling. Insulin resistance also induces the development of steatosis, progression of fibrosis and proinflammatory cytokine release and reduces the bioavailability of interferon. Suppressor of cytokine signalling 3 and protein tyrosine phosphatases are involved in blocking the intracellular signalling of interferon and insulin. Insulin resistance can be treated through diet, physical exercise and the use of insulin-sensitizing agents such as biguanides or glitazones. The TRIC-1 study demonstrated that adding metformin to routine treatment improves the possibilities of cure in women and in patients whose insulin sensitivity returns to normal during treatment.

Pioglitazone improves virological response to peginterferon alpha-2b/ribavirin combination therapy in hepatitis C genotype 4 patients with insulin resistance

BACKGROUND & AIM

Insulin resistance (IR) affects sustained virological response (SVR). The use of insulin-sensitizing agents has been proposed to improve therapy outcome. The safety and efficacy of pioglitazone on insulin sensitivity and SVR in treatment-naïve patients with chronic hepatitis C (CHC) genotype 4 with IR receiving standard antiviral therapy were evaluated in a randomized-controlled study.

METHODS

Ninety-seven previously untreated patients with CHC and IR [homeostasis model assessment (HOMA>2)] were randomly assigned into two arms; (arm A; n=48) were given pioglitazone 30 mg/day combined with peginterferon (Peg-IFN)-alpha-2b/ribavirin (RBV) for 48 weeks, and (arm B; n=49) were given standard of care (Peg-IFN-alpha-2b/RBV for 48 weeks); HOMA index and hepatitis C virus RNA (HCV RNA) levels were measured at baseline, during therapy and follow-up. Treatment was stopped in patients without an early virological response or those who were HCV RNA positive at 24 weeks.

RESULTS

Baseline data of both groups were comparable, with no significant statistical differences. The percentages of rapid virological response (RVR) and SVR were significantly higher in patients given triple therapy compared with standard of care (27.08 vs. 6.1%; P=0.006 and 60.4 vs. 38.7%; P=0.04 respectively); patients in arm A showed a greater decrease in the HOMA index than those in arm B (-1.8 +/- 0.3, -2.1 +/- 0.3 vs. -1.1 +/- 0.6, -1.3 +/- 0.7) at week 24 and at the end of follow-up (P=0.001 at both time points). The triple therapy was well tolerated.

CONCLUSIONS

A combination of pioglitazone, Peg-IFN-alpha-2b and ribavirin increased RVR, SVR and decreased IR, compared with patients given Peg-IFN plus ribavirin without an increase in adverse events.

Hepatic steatosis in genotype 4 chronic hepatitis C patients: implication for therapy

BACKGROUND AND AIM

The association of hepatitis C virus genotype 4 (HCV-4) with hepatic steatosis has not been clarified. We aimed to determine the parameters associated with steatosis among HCV-4 patients and to assess the effect of steatosis on treatment with peginterferon and ribavirin.

METHODS

In a prospective study; 131 nondiabetic genotype 4 CHC patients were enrolled for analysis, treated with peginterferon-α-2b/ribavirin. Histopathologic, anthropometric, clinical, biochemical features, and insulin resistance (IR) estimated by the homeostasis model assessment index (HOMA-IR).

RESULTS

Hepatic steatosis was present in 58 patients (44.2%); 62% of them experienced mild steatosis. In univariable analysis, steatosis was associated with HOMA-IR, body mass index, waist circumference, serum triglycerides, cholesterol level, systolic hypertension, and histologic scores for inflammation and fibrosis. Multivariate analysis revealed that body mass index, waist circumference, and HOMA-IR were found to be significantly associated with steatosis. IR but not steatosis was associated with a lower rate of sustained virologic response when adjusted for known factors that predict response (odds ratio: 0.16, 95% CI 0.046-0.59, P=0.005).

CONCLUSIONS

In HCV-4 patients, the prevalence of steatosis was 44.2%; the majority (62%) has mild steatosis. Steatosis was significantly associated with metabolic factors. IR but not steatosis was independently associated with lower sustained virologic response.

Ethnicity and body mass index are associated with hepatitis C presentation and progression

BACKGROUND & AIMS

Ethnicity and the metabolic syndrome are believed to affect progression of hepatitis C virus (HCV) infection, but the interaction between these factors is unknown. We evaluated the association between elements of the metabolic syndrome and ethnicity in the histologic progression of HCV in a large, diverse cohort.

METHODS

We retrospectively evaluated clinical data and liver biopsy samples from 812 patients who had no cause of liver disease other than HCV infection. Liver biopsies were scored for steatosis, necroinflammatory activity, and fibrosis. For each patient with a known risk factor for viral acquisition, fibrosis index was calculated as an indicator of disease progression.

RESULTS

Hispanics had significantly higher fibrosis index (0.13 +/- 0.09) than non-Hispanic whites (0.11 +/- 0.07) and African Americans (0.10 +/- 0.06; P = .001). Fibrosis index correlated with body mass index (BMI), older age at infection, ethnicity, and degree of steatosis. Cirrhosis was present in 50% of Hispanics, 38% of non-Hispanic whites, and 24% of African Americans (P < .001). The presence of cirrhosis was associated additionally with older age, longer duration of infection, BMI, alcohol consumption, and diabetes. In multivariate analysis, only BMI and ethnicity were associated with both fibrosis index and presentation with cirrhosis. Patients with higher BMIs, diabetes mellitus, and steatosis had higher degrees of necroinflammation.

CONCLUSIONS

Ethnicity and BMI each were associated with the progression of fibrosis and the presence of cirrhosis. Hispanics had the highest fibrosis index and prevalence of cirrhosis, whereas African Americans had the lowest. Ethnic differences in fibrosis index and cirrhosis persisted after controlling for elements of metabolic syndrome.

Whole-body insulin sensitivity index is a highly specific predictive marker for virological response to peginterferon plus ribavirin therapy in chronic hepatitis C patients with genotype 1b and high viral load

Insulin resistance is a candidate predictive factor for virological response to peginterferon plus ribavirin (PEG/RBV) therapy in chronic hepatitis C patients. We examined whether indices of insulin resistance could serve as a predictor of sustained virological response (SVR). Fifty-one patients with genotype 1b and high viral load who received PEG/RBV therapy for 48 weeks were included. Homeostasis model assessment of insulin resistance (HOMA-IR) and whole-body insulin sensitivity index (WBISI) calculated from the 75-g oral glucose tolerance test and serum levels of soluble tumor necrosis factor receptor 2 (sTFNR2) were evaluated before therapy. Patients who achieved SVR had significantly lower HOMA-IR and sTNFR2 levels and a higher WBISI compared with non-SVR patients. The positive predictive value for SVR was 0.653 for a HOMA-IR of <2 and 0.846 for a WBISI of 6 or higher. WBISI may serve as a highly specific predictor for SVR in PEG/RBV therapy.

Predicting clinical and histologic outcomes based on standard laboratory tests in advanced chronic hepatitis C

BACKGROUND & AIMS

Predictors of clinical outcomes and histologic progression among patients with chronic hepatitis C and advanced fibrosis are poorly defined. We developed statistical models to predict clinical and histologic outcomes in such patients.

METHODS

Baseline demographic, clinical, and histologic data from Hepatitis C Antiviral Long-Term Treatment Against Cirrhosis (HALT-C) Trial participants were subjected to multivariate analyses to determine their ability to predict clinical outcomes (ascites, spontaneous bacterial peritonitis, Child-Turcotte-Pugh score >or=7 on 2 consecutive visits, variceal bleeding, hepatic encephalopathy, and liver-related death) and histologic outcome (>or=2-point increase in Ishak fibrosis stage) during the 3.5 years of the trial.

RESULTS

Of 1050 randomized patients, 135 had 1 or more clinical outcomes a median of 23 (range, 1-45) months after randomization. Factors associated with a clinical outcome in multivariate analyses were higher aspartate aminotransferase/alanine aminotransferase ratio, lower albumin, lower platelet count, higher total bilirubin, and more advanced Ishak fibrosis score (P < .0001). The cumulative 3.5-year incidence of a clinical outcome was 2% in the lowest and 65% in the highest risk group. Of 547 patients without cirrhosis at baseline and at least 1 follow-up biopsy, 152 had a histologic outcome. Independent variables associated with a histologic outcome were higher body mass index, lower platelet count, and greater hepatic steatosis (P < .0001).

CONCLUSIONS

In patients with chronic hepatitis C and advanced fibrosis, risk of clinical complications and fibrosis progression during 3.5 years can be predicted using baseline laboratory tests and histologic data. Our models may be useful in counseling patients and determining the frequency of monitoring.

Diabetes mellitus is associated with impaired response to antiviral therapy in chronic hepatitis C infection

Insulin resistance may promote hepatic fibrosis in chronic hepatitis C (HCV) and has emerged as a cofactor in failure to achieve sustained viral response (SVR).

AIMS

(1) To assess the association of diabetes mellitus (DM) in HCV patients to the severity of hepatic fibrosis and to the response to antiviral treatment. (2) To assess the safety of pegylated interferon and ribavirin combination therapy (Peg IFN/RBV) in diabetic HCV patients. Methods HCV diabetics (n=61) were identified. A 2:1 matching control group was used to identify independent factors of advanced fibrosis and treatment failure.

RESULTS

Compared to HCV non-diabetics, HCV diabetics were more likely to have steatosis (P<0.0001) and advanced fibrosis (P=0.003). Patients' age, Caucasian ethnicity, obesity, and histologic activity index were independently associated with advanced fibrosis (P<0.05). Only 23% of HCV diabetics achieved SVR compared to 46% of HCV non-diabetics (P=0.003). DM, genotype 1, high baseline viral load, and African- American ethnicity were independently associated with less SVR (P<0.05). Significant adverse events were more common in HCV diabetics compared to HCV non-diabetics (P=0.001). Side effects did not increase in patients receiving PEG IFN/RBV and insulin sensitizers. Conclusion DM was associated with impaired virologic response to PEG IFN/RBV in HCV patients. Adverse events during therapy were more frequent in diabetic compared to non-diabetic HCV patients.

Early prediction of sustained virological response at day 3 of treatment with albinterferon-alpha-2b in patients with genotype 2/3 chronic hepatitis C

BACKGROUND

Albinterferon-alpha-2b (albIFN) is a long-acting fusion polypeptide composed of albumin and IFN-alpha-2b. In a phase 2 study of albIFN 1500 mug q2wk or q4wk in patients with genotype 2/3 chronic hepatitis C, albIFN demonstrated sustained virological response (SVR) rates of 62-77% (intent-to-treat population).

AIMS

To assess the association of initial viral kinetics during albIFN therapy with baseline factors and SVR prediction.

METHODS

In all, 43 patients were treated with albIFN 1500 mug (q2wk/q4wk) plus ribavirin (RBV) 800 mg/day for 24 weeks. Hepatitis C virus (HCV)-RNA levels were measured by real-time polymerase chain reaction, insulin resistance by homeostasis model assessment of insulin resistance (HOMA-IR) and serum albIFN levels by enyzme-linked immunosorbent assay. Prediction analysis was performed in a per protocol 28-patient subset who were > or =80% adherent to albIFN/RBV and had HCV-RNA levels measured at treatment day 3.

RESULTS

Day-3 HCV-RNA level and first-phase viral decline as well as second-phase slope of viral decline were significantly associated with SVR. In adherent patients, 82.1% had a day-3 viral load <4.2 log(10) IU/ml or first-phase decline >1.25 log(10) IU/ml, which was predictive of SVR, both positively (95.7%; sensitivity: 100%) and negatively (100%; specificity: 83.3%). As low first-phase decline was associated with a high pretreatment HOMA-IR index (P=0.004) and a low day-3 serum albIFN level (P=0.01).

CONCLUSIONS

First-phase viral decline with albIFN/RBV was predictive of SVR in this study and may be modulated in part by IR.

Gene expression profile associated with superimposed non-alcoholic fatty liver disease and hepatic fibrosis in patients with chronic hepatitis C

BACKGROUND

Hepatic steatosis occurs in 40-70% of patients chronically infected with hepatitis C virus [chronic hepatitis C (CH-C)]. Hepatic steatosis in CH-C is associated with progressive liver disease and a low response rate to antiviral therapy.

AIM

Gene expression profiles were examined in CH-C patients with and without hepatic steatosis, non-alcoholic steatohepatitis (NASH) and fibrosis.

METHODS

This study included 65 CH-C patients who were not receiving antiviral treatment. Total RNA was extracted from peripheral blood mononuclear cells, quantified and used for one-step reverse transcriptase-polymerase chain reaction to profile 153 mRNAs that were normalized with six 'housekeeping' genes and a reference RNA. Multiple regression and stepwise selection assessed differences in gene expression and the models' performances were evaluated.

RESULTS

Models predicting the grade of hepatic steatosis in patients with CH-C genotype 3 involved two genes: SOCS1 and IFITM1, which progressively changed their expression level with the increasing grade of steatosis. On the other hand, models predicting hepatic steatosis in non-genotype 3 patients highlighted MIP-1 cytokine encoding genes: CCL3 and CCL4 as well as IFNAR and PRKRIR. Expression levels of PRKRIR and SMAD3 differentiated patients with and without superimposed NASH only in the non-genotype 3 cohort (area under the receiver operating characteristic curve=0.822, P-value 0.006]. Gene expression signatures related to hepatic fibrosis were not genotype specific.

CONCLUSIONS

Gene expression might predict moderate to severe hepatic steatosis, NASH and fibrosis in patients with CH-C, providing potential insights into the pathogenesis of hepatic steatosis and fibrosis in these patients.

Impact of obesity, steatosis and insulin resistance on progression and response to therapy of hepatitis C

Clinical progression of chronic hepatitis C depends on several cofactors, which also have a negative affect on the rate of response to interferon-alpha-based therapy. Given the current worldwide prevalence of the metabolic syndrome, the impact of obesity and insulin resistance, and of their histopathological correlate, hepatic steatosis, on the natural history and management of chronic hepatitis C is undoubtedly very important. We will review some of the current knowledge on the clinical consequences of overweight/obesity, steatosis and insulin resistance on chronic hepatitis C, and discuss how this issue may be dealt with in clinical practice.

Molecular mechanisms of insulin resistance in chronic hepatitis C

It is now widely recognized that chronic hepatitis C (CHC) is associated with insulin resistance (IR) and type 2 diabetes, so can be considered a metabolic disease. IR is most strongly associated with hepatitis C virus (HCV) genotype 1, in contrast to hepatic steatosis, which is associated with genotype 3 infection. Apart from the well-described complications of diabetes, IR in CHC predicts faster progression to fibrosis and cirrhosis that may culminate in liver failure and hepatocellular carcinoma. More recently, it has been recognized that IR in CHC predicts a poor response to antiviral therapy. The molecular mechanisms for the association between IR and HCV infection are not well defined. This review will elaborate on the clinical associations between CHC and IR and summarize current knowledge regarding the molecular mechanisms that potentially mediate HCV-associated IR.

Predicting the probable outcome of treatment in HCV patients

Hepatitis C virus (HCV) is a major cause of chronic liver disease infecting more than 170 million people worldwide. HCV produces a wide gamut of manifestations varying from mild self-limiting disease to cirrhosis and hepatocellular carcinoma. A variety of viral, environmental and host genetic factors contribute to the clinical spectrum of patients infected with HCV and influence response to interferon (IFN) therapy. Predicting the probable outcome of treatment in patients with HCV infection has always been a challenging task. Treatment of HCV by pegylated interferon (peg-IFN) plus ribavirin eradicates the virus in approximately 60% of patients - HCV genotype 1 (42-51% response rates) and genotypes 2 and 3 (76-84% response rates); however, a significant number of patients do not respond to therapy or relapse following discontinuation of treatment or have significant side effects that preclude further treatment. Accurately predicting the patients who will respond to therapy is becoming increasingly important, both from the point of patient care and also with respect to the healthcare cost as clinicians need to continue treatment in patients who will respond and stop treatment in patients who are unlikely to respond. Viral RNA measurements and genotyping are used to optimize treatment as a low viral load and nongenotype 1 is more likely to be associated with sustained virological response (SVR). Rapid virological response (RVR) defined by undetectable HCV RNA at 4 weeks of treatment is increasingly being recognized as a powerful tool for predicting treatment response. A variety of host factors including single nuclear polymorphisms (SNPs) of IFN response genes, insulin resistance, obesity, ethnicity, human leukocyte antigens and difference in T-cell immune response has been found to modulate the response to antiviral treatment. The presence of severe fibrosis/cirrhosis on pretreatment liver biopsy predicts a poor response to treatment. Recent studies on gene expression profiling and characterization of the liver and serum proteome provide options to accurately predict the outcome of patients infected with HCV in the future. Future studies on the factors that predict treatment response and tailoring treatment based on this is required if we are to conquer this disease.

Hepatitis C virus infection: molecular pathways to steatosis, insulin resistance and oxidative stress

The persistent infection with hepatitis C virus is a major cause of chronic liver disease worldwide. However, the morbidity associated with hepatitis C virus widely varies and depends on several host-related cofactors, such as age, gender, alcohol consumption, body weight, and co-infections. The objective of this review is to discuss three of these cofactors: steatosis, insulin resistance and oxidative stress. Although all may occur independently of HCV, a direct role of HCV infection in their pathogenesis has been reported. This review summarizes the current understanding and potential molecular pathways by which HCV contributes to their development.

Decline in male sexual desire, function, and satisfaction during and after antiviral therapy for chronic hepatitis C

BACKGROUND & AIMS

The recommended therapy for chronic hepatitis C, pegylated interferon and ribavirin for 24 or 48 weeks, has many known adverse side effects. The aim of this study was to evaluate the impact of antiviral therapy on male sexual health.

METHODS

As part of the Study of Viral Resistance to Antiviral Therapy of Chronic Hepatitis C (Virahep-C), 260 men treated with pegylated interferon alfa-2a and ribavirin completed self-administered questionnaires concerning sexual desire, sexual function, including erectile and ejaculatory function, and sexual satisfaction before, during, and after treatment.

RESULTS

Before therapy, 37% of men reported at least some degree of impairment in sexual desire and 44% reported dissatisfaction with their sexual life, while 26% reported impairment in erectile and 22% in ejaculatory function. During therapy, significant declines were observed in all components of sexual health compared with pretreatment. At the end of therapy (24 or 48 weeks), an estimated 38%-48% of men reported that overall sexual function was worse than before treatment. African American patients reported less impairment in sexual desire and satisfaction than Caucasian American patients during therapy. By 24 weeks after treatment, sexual desire and satisfaction improved and were comparable to baseline levels. However, among men who received 48 weeks of therapy, the estimated percentage of men reporting posttreatment erectile or ejaculatory problems remained higher than baseline, although persistent erectile impairment was limited to Caucasian American patients.

CONCLUSIONS

Sexual impairment is common among men with chronic hepatitis C undergoing therapy with pegylated interferon and ribavirin and should be considered as a potential side effect of antiviral therapy.

Influence of insulin resistance on hepatic fibrosis and steatosis in hepatitis C virus (HCV) mono-infected compared with HIV-HCV co-infected patients

BACKGROUND

Insulin resistance (IR), the major feature of the metabolic syndrome, is also common in patients with chronic HCV infection. Liver fibrosis and steatosis are known potential outcome of chronic hepatitis B or C infection. Studies have shown that HIV positive individuals co-infected with HCV have more rapid live disease progression than those with HIV alone. Few data have reported the influence of IR on steatosis and fibrosis in the context of HIV-HCV coinfection.

AIM

To test the association among insulin resistance (IR), liver fibrosis and liver steatosis in HIV-HCV and HCV-infected patients.

PATIENTS AND METHODS

A total of 170 HIV-HCV-infected patients matched by age, gender and genotype with 170 HCV mono-infected patients were included. Patients were considered to be IR when the homeostasis model assessment of IR >2. Significant fibrosis was considered if METAVIR >or=F2 and significant steatosis if >or=10%.

RESULTS

Insulin resistance was independently associated in HCV patients with fibrosis [odds ratio (OR) = 2.04 (95% CI 1.02-4)], a body mass index (BMI) >25 kg/m(2) [OR = 3.33 (1.47-7.69)] and steatosis [OR = 3.33 (1.67-6.67)]. Fibrosis >or=F2 was associated in HCV patients with high liver activity grade (>or=A2) [OR = 8.33 (3.85-16.67)], male gender [OR = 3.03 (1.33-7.14)] and IR [OR = 2.44 (1.15-5)]. In HIV-HCV patients, >or=A2 [OR = 5.56 (1.64-20)] was associated with fibrosis. Steatosis >or=10% was associated in HCV patients with IR [OR = 3.13 (1.59-6.25) and >or=F2 (OR = 2.22 (1.15-4.17)]. In HIV-HCV, a BMI >25 kg/m(2) [OR = 3.85 (1.64-9.10)], >or=A2 [OR = 2.16 (1.02-4.55); P = 0.044] and nucleoside reverse transcriptase inhibitor [OR = 3.61 (1.19-10.96); P = 0.023] were independently associated with significant liver steatosis.

CONCLUSIONS

Insulin resistance is associated with liver fibrosis and steatosis in HCV mono-infected, but not in HIV-HCV co-infected patients. Significant liver fibrosis is associated with IR independent of liver steatosis only in HCV mono-infected patients.

Amino acid substitutions in the hepatitis C virus core region of genotype 1b are the important predictor of severe insulin resistance in patients without cirrhosis and diabetes mellitus

Previous studies provided a direct experimental evidence for the contribution of HCV core protein in the development of insulin resistance (IR), but the clinical impact of HCV core region on IR is still not clear. The present study evaluated the impact of Amino acid (aa) substitutions of HCV-1b core region on IR in 123 Japanese patients infected with HCV-1b without cirrhosis and diabetes mellitus, and investigated the treatment efficacy of 48-week pegylated interferon (PEG-IFN) plus ribavirin (RBV) according to HOMA-IR values. Patients with IR (HOMA-IR > or = 2.5) and severe IR (HOMA-IR > or = 3.5) were present in 51.2% and 27.6%, respectively. Multivariate analysis identified body mass index (> or = 25 kg/m(2)) and hepatocyte steatosis (> or = 5%) as significant determinants of IR. Furthermore, multivariate analysis identified hepatocyte steatosis (> or = 5%), aa substitutions of the core region (Gln70 (His70) and/or Met91), and age (> or = 55 years) as significant determinants of severe IR. Especially, significantly lower proportions of patients with Gln70 (His70) and/or Met91 were noted among those without severe IR (59.6%) than those with severe IR (82.4%). The rates of sustained virological response in patients with IR (50.0%) were not significantly different from those without IR (52.9%). Furthermore, the rates of non-virological response in patients with IR (28.9%) were not significantly also different from those without IR (20.6%). In conclusion, the present study indicated that substitutions of HCV-1b core region were the important predictor of severe IR in patients without cirrhosis and diabetes mellitus, but HOMA-IR values might be not useful as predictors of 48-week PEG-IFN plus RBV therapy.

Fenofibrate and PBA prevent fatty acid-induced loss of adiponectin receptor and pAMPK in human hepatoma cells and in hepatitis C virus-induced steatosis

Adiponectin receptors play a key role in steatosis and inflammation; however, very little is known about regulation of adiponectin receptors in liver. Here, we examined the effects of palmitate loading, endoplasmic reticulum (ER) stress, and the hypolipidemic agent fenofibrate on adiponectin receptor R2 (AdipoR2) levels and AMP-activated protein kinase (AMPK) in human hepatoma Huh7 cells and in Huh.8 cells, a model of hepatitis C-induced steatosis. Palmitate treatment reduced AdipoR2 protein and basal AMPK phosphorylation in Huh7 cells. Fenofibrate treatment preserved AdipoR2 and phosphorylated AMPK (pAMPK) levels in palmitate-treated cells accompanied by reduced triglyceride (TG) accumulation and less activation of ER stress markers CCAAT/enhancer binding (C/EBPbeta) and eukaryotic translation initiation factor 2 alpha. ER stress agents thapsigargin and tunicamycin suppressed AdipoR2 and pAMPK levels in Huh7 cells, while fenofibrate and the chemical chaperone 4-phenylbutyrate (PBA) prevented these changes. AdipoR2 levels were lower in Huh.8 cells and fenofibrate treatment increased AdipoR2 while reducing activation of c-Jun N-terminal kinase and C/EBPbeta expression without changing TG levels. Taken together, these results suggest that fatty acids and ER stress reduce AdipoR2 protein and pAMPK levels, while fenofibrate and PBA might be important therapeutic agents to correct lipid- and ER stress-mediated loss of AdipoR2 and pAMPK associated with nonalcoholic steatohepatitis.

Insulin resistance, serum adipokines and risk of fibrosis progression in patients transplanted for hepatitis C

In the nontransplant setting diabetes mellitus is a risk factor for disease progression in patients with chronic hepatitis C virus (HCV) infection. The impact of early insulin resistance on the development of advanced fibrosis, even in the absence of clinically apparent diabetes mellitus, is not known. Our aim was to determine whether the Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) can be used to identify insulin-resistant patients at risk for rapid fibrosis progression. Cohort study including patients transplanted for chronic HCV between January 1, 1995 and January 1, 2005. One hundred sixty patients were included; 25 patients (16%) were treated for diabetes mellitus and 36 patients (23%) were prediabetic, defined as HOMA-IR >2.5. Multivariate Cox regression analysis showed that insulin resistance (hazard ratio (HR) 2.07; confidence interval (CI) 1.10-3.91, p = 0.024), donor age (HR 1.33;CI 1.08-1.63, p = 0.007) and aspartate aminotransferase (HR 1.03;CI 1.01-1.05, p < 0.001) were significantly associated with a higher probability of developing advanced fibrosis, i.e. Knodell fibrosis stage 3 or 4, whereas steatosis (HR 0.94;CI 0.46-1.92, p = 0.87) and acute cellular rejection (HR 1.72;CI 0.88-3.36, p = 0.111) were not. In conclusion, posttransplant insulin resistance is strongly associated with more severe recurrence of HCV infection. HOMA-IR is an important tool for the identification of insulin resistance among patients at risk for rapid fibrosis progression after liver transplantation for HCV.

Host genetics, steatosis and insulin resistance among African Americans and Caucasian Americans with hepatitis C virus genotype-1 infection

Hepatic steatosis is the accumulation of fat in liver cells. Insulin resistance (IR) occurs when normal amounts of insulin do not stimulate insulin activity in cells. Both conditions have been described in hepatitis C virus (HCV) infection and are thought to be biologically related. This study examined the association of genetic variants with steatosis and IR among 167 African Americans and 184 Caucasian Americans with HCV genotype-1. Steatosis was defined as at least 5% of fat in cells on liver biopsy. IR was quantified as a score greater than 2 from the Homeostasis Model Assessment, version 2.2 (HOMA2-IR). Associations were investigated by estimating odds ratios separately by race. Statistically significant associations (p < 0.05) were observed for variants in interleukin-10 (IL10), leptin receptor (LEPR), interleukin-6 (IL6) and transforming growth factor beta-1 (TGF-beta1) for both outcomes. Some significant interactions were observed between IL10,LEPR and TGF-beta1 polymorphisms and HOMA2-IR scores when examining steatosis. The interaction of HOMA2-IR and IL10 was consistent in both races whereas for LEPR and TGF-beta1 the interactions were statistically significant in only one of the racial groups.These results could imply that some IL10,LEPR and TGF-beta1 polymorphisms may modify an association between steatosis and IR.

Hepatitis C virus and type 2 diabetes

This review focuses on the relationship between hepatitis C virus (HCV) infection and glucose metabolism derangements. Cross-sectional and longitudinal studies have shown that the chronic HCV infection is associated with an increased risk of developing insulin resistance (IR) and type 2 diabetes (T2D). The direct effect of HCV on the insulin signaling has been analyzed in experimental models. Although currently available data should be considered as preliminary, HCV seems to affect glucose metabolism via mechanisms that involve cellular pathways that have been implicated in the host innate immune response. IR and T2D not only accelerate the histological and clinical progression of chronic hepatitis C, but also reduce the early and sustained virological response to interferon-alpha-based therapy. Thus, a detailed knowledge of the mechanisms underlying the HCV-associated glucose metabolism derangements is warranted, in order to improve the clinical management of chronic hepatitis C patients.

Microsomal triglyceride transfer protein polymorphism (-493G/T) is associated with hepatic steatosis in patients with chronic hepatitis C

BACKGROUND

Hepatic steatosis may promote progression of chronic hepatitis C (CHC). Microsomal triglyceride transfer protein (MTP) is required for assembly and secretion of ApoB lipoprotein and is implicated in hepatitis C virus (HCV)-related steatosis. The MTP -493G/T polymorphism may promote liver fat accumulation, but its role in HCV-related steatosis is still unclear.

METHODS

Two hundred ninety-eight CHC patients were studied and genotyped for MTP -493G/T variants. Hepatic MTP mRNA expression and activity were determined in a subgroup.

RESULTS

Patients with grades 2/3 steatosis were older, had a higher body mass index (BMI), more advanced fibrosis and lower MTP mRNA expression and carried more often HCV genotype 3 and the MTP T allele. Age, BMI, HCV-3 and MTP T allele [odds ratio (OR) 2.05; 95% confidence interval (CI) 1.2-3.53; P=0.009] were independent risk factors for steatosis grades 2/3, and in HCV genotype non-3 patients, the MTP T allele was the strongest predictor for steatosis grade 2/3 (OR 2.17; 95% CI 1.22-3.86; P=0.008). Moreover, TT carriers had higher high-density lipoprotein (65.6+/-14.6 vs 56.1+/-16.2 mg/dl; P=0.003) and apolipoprotein AI (1.80+/-0.3 vs 1.60+/-0.3 g/L; P=0.005) levels than G allele carriers.

CONCLUSIONS

Chronic hepatitis C patients with the MTP -493T allele reveal higher grades of steatosis, indicating a relevant contribution to liver fat accumulation, particularly in HCV non-3 patients.

Insulin resistance predicts response to peginterferon-alpha/ribavirin combination therapy in chronic hepatitis C patients

BACKGROUND/AIMS

Insulin resistance (IR) might be associated with hepatitis C virus (HCV) infection. This study aimed to elucidate impact of IR and beta-cell function on the response to peginterferon-alpha (PEG-IFN)/ribavirin combination therapy in chronic hepatitis C (CHC) patients.

METHODS

Three hundred and thirty patients without overt diabetes were treated with combination therapy with (PEG-IFN)/ribavirin for 24 weeks. The IR and beta-cell function were evaluated by homeostasis model assessment of IR (HOMA-IR) and homeostasis model assessment of beta-cell function (HOMA-beta) before treatment.

RESULTS

HCV genotype, pretreatment HCV RNA level and pretreatment HOMA-IR, but not HOMA-beta, were independent factors associated with sustained virologic response (SVR). In 150 patients with genotype 1b infection, pretreatment HCV RNA level, HOMA-IR and age were independent predictors for SVR. The significantly lower SVR rate in high HOMA-IR patients was observed in 76 patients with high HCV RNA levels (>or=400,000IU/mL) who were defined as 'difficult-to-treat' patients. The mean HOMA-IR of 'difficult-to-treat' patients was significantly lower in 42 sustained responders than in 34 non-responders.

CONCLUSIONS

IR was associated with SVR to (PEG-IFN)/ribavirin therapy for CHC, especially among 'difficult-to-treat' patients. These findings suggested clinical application of pretreatment HOMA-IR could enable treatment outcome to be predicted and treatment regimens to be determined.

Insulin resistance is not a relevant predictor of sustained virological response to pegylated interferon plus ribavirin in HIV/HCV co-infected patients

BACKGROUND/AIMS

To evaluate the possible influence of baseline insulin resistance in sustained virological response.

METHODS

One hundred and fifty-five consecutive individuals from a multicentric cohort of HIV/HCV co-infected patients who underwent therapy with pegylated interferon plus ribavirin were included. The main outcome variable was sustained virological response, defined as undetectable plasma HCV RNA at week 24 after the end of the therapy. Insulin resistance was determined using the HOMA method.

RESULTS

Sustained virological response was achieved in 55 (36%) patients. Forty-two (38%) patients with a HOMA lower than 4 developed sustained virological response vs 13 (29%) of those with a HOMA above 4 (p=0.27). Analyses restricted to patients harbouring genotype 1 or 4 showed similar rates of sustained virological response among patients with a HOMA below and above 4 [19 (27%) vs 7 (24%); p=0.8]. In the multivariate analysis, genotype 3 [AOR 9.26; 95% CI 3.03-28.30; p<0.0001], a baseline HCV viral load below 600.000IU/mL [AOR 2.97; 95% CI 1.03-8.57; p=0.04] and baseline LDL cholesterol above 100mg/dL [AOR 6.62; 95% CI 1.97-22.19; p=0.002] were independently associated with sustained virological response.

CONCLUSIONS

Insulin resistance is not a relevant predictor of sustained virological response to pegylated interferon plus ribavirin in HIV/HCV co-infected patients.

Insulin resistance and metabolic syndrome in chronic liver diseases: old entities with new implications

Insulin resistance (IR) and metabolic syndrome have recently been implicated in the pathogenesis and progression of chronic liver diseases, especially chronic hepatitis C (CHC) and non-alcoholic fatty liver disease (NAFLD). In this review, we provide current information on their deleterious effect on the liver, with particular interest in those two entities. In NAFLD, IR causes both the accumulation of fat in hepatocytes and the progression to non-alcoholic steatohepatitis (NASH). Moreover, the presence of metabolic syndrome seems to be associated with severe fibrosis in NASH patients. In CHC, IR develops early in the course of the disease and precedes steatosis. It is also independently associated with histological severity and negatively affects treatment response, irrespective of genotype. Consequently, therapies targeting IR and metabolic syndrome could indirectly ameliorate the prognosis of both NAFLD and CHC. As specific therapies do not exist, patients with metabolic syndrome and CHC and NAFLD should be counseled to lose weight and ameliorate their glycemic control and lipid profile.

Metabolic syndrome, non-alcoholic fatty liver disease and hepatitis C virus: impact on disease progression and treatment response

Non-alcoholic fatty liver disease (NAFLD), a spectrum of liver disease ranging from simple steatosis to non-alcoholic steatohepatitis, is increasingly recognized as the hepatic manifestation of metabolic syndrome and is an important cause of liver-related morbidity and mortality. It is among the most common forms of liver disease. NAFLD reflects abnormal partitioning of fat, such that fat deposition is increased in the liver, and provides a link between NAFLD and the metabolic syndrome, a constellation of metabolic disorders that can also be associated with visceral fat or central adiposity. Together, the features of the metabolic syndrome presage overt diabetes and increase cardiovascular risk. Hepatitis C virus (HCV) appears to exacerbate the metabolic syndrome by eliciting increased insulin resistance (IR) and promoting truncal obesity. Moreover, the concomitant presence of HCV and NAFLD is associated with an increased likelihood of diabetes, hypertension and/or hypertriglyceridaemia. Metabolic abnormalities have been shown to influence response to treatment such that the presence of IR or obesity reduces the likelihood of a sustained virological response (SVR); conversely, SVR has been demonstrated to ameliorate IR and improve beta-cell function. Clinically, these data suggest that attention must be paid not only to optimizing antiviral response but also to screening for and treatment of the various components of the metabolic syndrome.

Treatment failure in hepatitis C: mechanisms of non-response

Hepatitis C virus (HCV) has evolved remarkable mechanisms that favor viral persistence by interfering with host innate and adaptive immune responses. These same mechanisms are likely to contribute to resistance to exogenously administered interferon used for HCV treatment. We review the host innate and adaptive immune responses in the context of HCV infection as well as the strategies by which these responses are subverted by the virus. In addition, the contribution of host factors, such as race and insulin resistance, to interferon non-responsiveness is discussed. Our progress in understanding the molecular underpinnings of interferon treatment failure in HCV infection has resulted in several promising and novel treatment strategies for HCV treatment non-responders.

Retreatment of chronic hepatitis C: who and how?

All but about 10% of patients with chronic hepatitis C (CHC) (predominantly those infected with genotype 1) can respond to some degree to 'combination' therapy with interferon (IFN) and ribavirin. The slower the virological response to treatment, the less likely sustained viral clearance will take place. Many factors influence response to antiviral therapy; most cannot be reversed (e.g. sex, age, cirrhosis, genotype and viral load). A sustained viral clearance is considerably facilitated by compliance with full-dose therapy for the prescribed time. The potential cause(s) for non-response need(s) to be ascertained before attempting retreatment. The 10% of patients who are true 'null' responders may respond to the new specifically targeted antiviral therapies but whether the response can be sustained off-therapy is unclear. Adjunctive therapies may facilitate response to retreatment if intolerance to treatment leading to diminished or absent doses was problematic in the past. Retreatment with a long-acting IFN and an adequate ribavirin dose (15 mg/kg), but given for 72 weeks in prior relapsers following 48 weeks of treatment, will enhance sustained virological response (SVR) rates. No benefit is gained from changing one pegylated IFNalpha (PEG IFNalpha) to another unless the treatment duration is extended. Only alpha-interferons are effective. For those individuals who still fail to achieve SVR, recruitment to trials of new treatments should be encouraged particularly for those with advanced liver disease. Lifestyle modification may be appropriate in attempt to reduce the chance of complications of liver disease, namely hepatocellular carcinoma, by smoking cessation, eliminating obesity and increasing coffee consumption.

Liver diseases and metabolic syndrome

Emerging attention has been paid to metabolic syndrome, which comprises several metabolic disorders including visceral obesity, diabetes mellitus, dyslipidemia, and hypertension. Whether the severity of each disease is mild to moderate, the comorbidity of these metabolic disorders has a serious impact on the development of atherosclerosis. Nonalcoholic fatty liver disease (NAFLD) is the major hepatic disorder in patients with metabolic syndrome, and indeed it is the most common cause of abnormal liver function tests in the working population in industrialized countries. In recent years, it has become recognized that NAFLD is no longer just a trivial disease, and a rather considerable proportion of the patients develop liver cirrhosis. Furthermore, chronic infection of hepatitis C virus also develops a pathological feature of steatohepatitis, and extended hepatic steatosis has a serious impact not only on the progression of hepatic fibrosis but also on the antiviral efficacy of interferon therapy. Emerging lines of studies indicated that insulin resistance, abnormal lipid metabolism, and dysregulation of cytokines/adipokines (e.g., tumor necrosis factor-alpha, adiponectin, and leptin) are profoundly involved in the pathogenesis of NAFLD. This review aims to integrate the reported evidence and to provide the current point of view for comprehensive understanding of the pathophysiology of steatohepatitis.

[Alcohol, steatohepatitis, insulin resistance and hepatitis C]

Patients with chronic hepatitis C have frequently other morbidities, either because they are frequent in the general population (metabolic syndrome) and/or because the route of contamination (chronic alcohol consumption succeeding to drug abuse). These co-morbidities have a harmfull impact on fibrosis progression during the natural history of HCV infection and reduce the efficacy of antiviral treatments. Thus, it is crucial to diagnose early and treat these different diseases which may be combined. They are the metabolic syndrome and/or chronic alcohol consumption resulting in insuline resistance, infection by the human immune deficiency virus or by the hepatitis B virus as well as chronic tobacco use or excessive consumption of cannabis. An optimal is based on a multidisciplinary approach to reduce fibrosis progression and improve the efficiency of antiviral therapies. However, the hepatologist has to come back to a global care, which is mandatory at the individual level as well as for the public health.

Improved outcomes in patients with hepatitis C with difficult-to-treat characteristics: randomized study of higher doses of peginterferon alpha-2a and ribavirin

Treatment response remains suboptimal for many patients with chronic hepatitis C, particularly those with genotype 1 and high levels of viremia. The efficacy of high-dose regimens of peginterferon alfa-2a and ribavirin was compared with conventional dose regimens in patients with features predicting poor treatment responses. Eligible treatment-naïve adults with genotype 1 infection, hepatitis C virus (HCV) RNA >800,000 IU/mL and body weight >85 kg were randomized to double-blind treatment with peginterferon alfa-2a at 180 or 270 microg/week plus ribavirin at 1200 or 1600 mg/day for 48 weeks (four regimens were evaluated). The primary endpoint was viral kinetics during the first 24 weeks of therapy. Among patients receiving peginterferon alfa-2a (270 microg/week) the magnitude of HCV RNA reduction was significantly greater than for patients randomized to the conventional dose of peginterferon alfa-2a (180 microg/week) for the pairwise comparison for ribavirin at 1600 mg/day (P = 0.036) and numerically greater for the pairwise comparison for ribavirin at 1200 mg/day (P = 0.060). Patients randomized to the highest doses of peginterferon alfa-2a (270 microg/week) and ribavirin (1600 mg/day) experienced the numerically highest rates of sustained virologic response (HCV RNA < 50 IU/mL) and the lowest relapse rate (47% and 19%, respectively). The arm with the higher doses of both drugs was less well-tolerated than the other regimens.

CONCLUSION

Higher fixed doses of peginterferon alfa-2a (270 microg/week) and ribavirin (1600 mg/day) may increase sustained virologic response rates compared with lower doses of both drugs in patients with a cluster of difficult-to-treat characteristics.

Treatment predictors of a sustained virologic response in hepatitis B and C

Treatment predictors are important tools for the management of therapy in patients with chronic hepatitis B and C virus (HBV, HCV) infection. In chronic hepatitis B, several pretreatment parameters have been identified for prediction of virologic response to interferon alfa-based antiviral therapies or treatment with polymerase inhibitors. In interferon alfa and pegylated interferon alfa-treated patients, low baseline HBV DNA concentrations, HBV genotype A (B), and high baseline ALT levels are significantly associated with treatment response. In patients treated with nucleos(t)ide analogues, low baseline HBV DNA but not viral genotype is positively associated with virologic response. During treatment the best predictor of response is HBV DNA kinetics. Early viral suppression is associated with favourable virologic response and reduced risk for subsequent resistance mutations. For the current standard treatment with pegylated interferon alfa and ribavirin in patients with chronic hepatitis C, infection with HCV genotypes 2 and 3, baseline viral load below 400,000-800,000 IU/ml, Asian and Caucasian ethnicity, younger age, low GGT levels, absence of advanced fibrosis/cirrhosis, and absence of steatosis in the liver have been identified as independent pretreatment predictors of a sustained virologic response. After initiation of treatment, initial viral decline with undetectable HCV-RNA at week 4 of therapy (RVR) is the best predictor of sustained virologic response independent of HCV genotype.