Eradication of hepatitis C virus by interferon improves whole-body insulin resistance and hyperinsulinaemia in patients with chronic hepatitis C

Iron homeostasis and insulin sensitivity: unraveling the complex interactions

Diabetes has arisen as a noteworthy global health issue, marked by escalating incidence and mortality rates. Insulin, crucial for preserving euglycemia, acts as a vital energy provider for various tissues. Iron metabolism notably plays a significant role in the development of insulin resistance, a key factor in the onset of various metabolic disorders. The intricate interaction between iron and insulin signaling encompasses complex regulatory mechanisms at the molecular level, thereby impacting cellular reactions to insulin. The intricate interplay between insulin and glucagon, essential for precise regulation of hepatic glucose production and systemic glucose levels, may be influenced by certain microelements for instance zinc, copper, iron, boron, calcium, cobalt, chromium, iodine, magnesium and selenium. While significant progress has been achieved in elucidating the pathophysiological connections between iron overload and glucose metabolism, our understanding of the involvement of the Fenton reaction and oxidative stress in insulin resistance influencing many chronical conditions remains limited. Furthermore, the exploration of the multifaceted roles of insulin in the human body continues to be a subject of active investigation by numerous scientific researchers. This review comprehensively outlines the potential adverse impact of iron overload on insulin function and glucose metabolism. Additionally, we provide a synthesis of findings derived from various research domains, encompassing population studies, animal models, and clinical investigations, to scrutinize the multifaceted relationship between iron and insulin sensitivity. Moreover, we delineate instances of correlations between serum iron levels and various medical conditions, including the diabetes also gestational diabetes and obesity.

Hepatitis C Infection as a Risk Factor for Hypertension and Cardiovascular Diseases: An EpiTer Multicenter Study

Hepatitis C infection is one of the main reasons for liver cirrhosis and hepatocellular carcinoma. In recent years, more and more is being heard about extrahepatic manifestations of the hepatitis C infection including its possible influence on the development of hypertension and cardiovascular diseases. In the given work, the frequency analysis of the incidence of hypertension and cardiovascular diseases among 2898 HCV-infected patients treated in Poland and the assessment of their relevance to the HCV genotype and the progression of liver fibrosis can be found. The prevalence of hypertension in the group of analyzed patients was 39% and was significantly associated with old age (OR = 1.08 (1.07-1.08)) and female sex, as well as the progression of liver fibrosis (OR = 1.54 (1.29-1.85)). Hypertension was found in 47.6% of patients with F4 fibrosis, 42.1% of patients with F3 fibrosis, and 25% of patients with F1 fibrosis. The incidence of cardiovascular disease in the studied group of patients was as follows: all incidents, 131 (4.52%); including ischemic heart disease 104, (3.95%); stroke, 2 (0.07%); atherosclerosis, 21 (0.72%); and aneurysms, 4 (0.14%). The obtained results prove that the prevalence of cardiovascular diseases is significantly associated with the advanced age of patients and the progression of liver fibrosis. The relevance of sex and the HCV genotype to the prevalence frequency of cardiovascular diseases in the study group has not been proven. This being the case, no differences in the frequency of their incidence depending on the HCV genotype, including genotype 3, was found. Hepatitis C infection as a non-classical risk factor for cardiovascular disease and hypertension does require further studying.

HCV Genotype Has No Influence on the Incidence of Diabetes-EpiTer Multicentre Study

HCV infection is one of the main reasons for liver cirrhosis and hepatocellular carcinoma. In recent years, one finds more and more extrahepatic manifestations of HCV infection, including its possible influence on the development of diabetes. In the presented work, one finds the frequency analysis of the incidence of diabetes among 2898 HCV infected patients treated in Poland, and the assessment of their relevance to the HCV genotype and the progression of fibrosis. The results indicate that the hepatitis C infection seems to be a risk factor for diabetes in persons with more advanced liver fibrosis, for older people, and for the male gender. Thus, one found no differences regarding the frequency of its incidence depending on HCV genotype, including genotype 3.

Eradication of hepatitis C virus with direct-acting antivirals improves glycemic control in diabetes: A multicenter study

Background and Aim

Hepatitis C virus (HCV) infection causes insulin resistance and diabetes as extrahepatic manifestations. We aimed to analyze the effect of HCV eradication by direct‐acting antiviral (DAA) agents on glucose tolerance.

Methods

The hemoglobin A1c (HbA1c) of 272 patients with HCV infection who achieved a sustained virologic response (SVR) was analyzed at baseline before DAA treatment, at the end of DAA therapy (ETR), and 12 weeks after therapy (Post12W).

Results

There were no significant differences in HbA1c between baseline, ETR, and Post12W in the overall patients. When the data were stratified according to the presence or absence of diabetes, median HbA1c significantly decreased from baseline (7.2%) to ETR (6.8%) and Post12W (6.8%) in the 55 patients with diabetes, whereas there were no significant changes in the patients without diabetes. Basal HbA1c, fasting plasma glucose, and age were independently associated with the changes in HbA1c according to multivariate analysis, and the predictive formula for changes in HbA1c was found to be ΔHbA1c (%) = 1.449–0.4* HbA1c (%) + 0.012 × Age (year). There were no changes in body mass in diabetic or nondiabetic patients. In diabetic patients taking medication, 63.4% of patients needed less medication.

Conclusions

Eradication of HCV improves glycemic control, indicated by a 0.4% decrease in HbA1c in diabetes.

Improvement of hyperuricemia in chronic hepatitis C patients receiving directly acting antiviral agents

BACKGROUND AND AIM

Hepatitis C virus eradication via the use of antivirals ameliorates metabolic profiles. The changes in serum uric acid (SUA) levels in chronic hepatitis C patients who receive antivirals are not well understood. We aimed to address this issue by comparing the SUA changes before and after the achievement of a sustained virological response (which is defined as hepatitis C virus RNA seronegativity at 12 weeks after the end of treatment).

METHODS

Two hundred and thirteen sustained virological response patients who were treated by directly acting antivirals were consecutively enrolled. Pretreatment and post-treatment SUA levels were compared. Hyperuricemia was defined as a uric acid level > 7.0 mg/dL in men and > 6.0 mg/dL in women.

RESULTS

The SUA levels significantly decreased after treatment, as compared to the pretreatment levels (5.6 ± 1.5 vs 6.0 ± 1.7 mg/dL, respectively; P < 0.001). The proportion of hyperuricemia incidences significantly decreased after treatment (25.8% vs 35.7%, respectively; P = 0.001). The improvement was only observed in patients with a fibrosis-4 index (FIB-4) < 6.5 (25.7% vs 37.1%, P = 0.001) but not in those patients with a FIB-4 ≧ 6.5 (26.3% vs 28.9%, P = 1.00). A multivariate analysis revealed that the factor that was associated with significantly decreased SUA levels was FIB-4 < 6.5 (odds ratio [OR]/95% confidence interval [CI]: 3.22/1.04-9.95, P = 0.04) and estimated glomerular filtration rate < 60 mL/min/1.73 m2 (OR/CI: 4.34/1.94-9.73, P < 0.001). There existed a trend of a higher proportion of patients with significant SUA improvement along with the decrement of FIB-4 (29.7%, 25%, and 10.5% in patients with FIB-4 < 3.25, 3.25-6.5, and > 6.5, respectively; trend P = 0.03).

CONCLUSIONS

SUA levels were significantly decreased in chronic hepatitis C patients after viral eradication. The improvement was particularly enhanced in patients with mild liver disease.

Effect of HCV treatment response on insulin resistance: A systematic review and meta-analysis

Sustained virological response (SVR) in hepatitis C virus (HCV) patients treated with pegylated interferon α-2a and ribavirin is associated with reduced insulin resistance (IR), measured as a reduction of homeostasis model assessment (HOMA) scores after 24 weeks of therapy, and reduced fasting serum insulin and serum glucose levels. The present meta-analysis aimed to evaluate the effect of HCV treatment response on IR in HCV patients who achieved SVR and those who did not (non-SVR) after receiving interferon (IFN)-based therapy. The PubMed, Cochrane and Embase databases were searched using combinations of the following search terms: ‘HCV’, ‘hepatitis C’, ‘interferon’, ‘antiviral’, ‘treatment response’ and ‘insulin resistance’. The incidence of IR, HOMA-IR and HOMA-β, as well as fasting glucose and fasting insulin levels, were summarized in terms of basal values and values after the end of treatment for each study. A total of 8 studies were included in the final analysis. There was no significant difference in the reduction in IR between the SVR and non-SVR groups (odds ratio, 0.995; 95% CI=0.613–1.616; P=0.984). However, the SVR group had a significantly higher mean reduction in HOMA-IR (difference in means=−0.485; 95%CI=−0.713 to −0.256; P<0.001) and HOMA-β (difference in means=−15.448; 95%CI=−23.326 to −7.570; P<0.001) compared to the non-SVR group. In conclusion, HCV patients who achieved SVR after IFN-based therapy exhibited improvement in HOMA-IR and HOMA-β. The present results suggest that clinical management of IR and serum glucose levels may be an important way to impact the therapeutic response in HCV patients.

The association of hepatitis c virus infection status with serum glucose levels

Background

Hepatitis C virus (HCV) infection is commonly associated with a disturbance of glucose metabolism. However, there have been conflicting reports on whether the clearance of the HCV may be followed by changes of serum blood glucose and insulin resistance. The aim of the present study was to evaluate the impact of HCV and antiviral treatment on serum glucose levels and other glucose metabolism parameters.

Methods

A retrospective analysis of 306 HCV-infected patients was performed. Fasting serum blood glucose (FBG) levels in these patients were compared with that of 325 healthy individuals. Serum parameters of glucose metabolism were measured in 183 patients with chronic hepatitis C at baseline, at the end of interferon α-2b plus ribavirin treatment, and at 24 weeks post-treatment.

Results

Patients with HCV infection had significantly higher FBG level than healthy controls (5.57 ± 0.74 vs. 5.11 ± 0.83 mmol/l, P < 0.001). After antiviral treatment, we found a significant reduction in FBG levels regardless of the outcome of treatment. However, after stopping treatment the serum FBG levels were significantly elevated in the sustained virological response (SVR) and non-responder groups, and maintained high level until week 24 post-treatment. In both groups, the levels of serum FBG after 24 weeks post-treatment were still lower than pre-treatment levels. In sustained responders, fasting insulin (P = 0.007), C-peptide (P < 0.001) and HOMA-IR (P < 0.001) significantly decreased, and the insulin sensitivity index (ISI) increased (P < 0.001) at the end of the treatment comparing with pre-treatment levels, while no significant difference was observed in non-responder group. HOMA-β values were increased in both groups at the end of treatment (both P < 0.001).

Conclusion

The total serum FBG level in HCV infected patients was higher than that in healthy controls. Clearance of HCV was associated with reduced glucose and improved insulin resistance.

[Chronic HCV infection: An internist's opinion (Part 2)]

Hepatitis C virus (HCV) infection results in not only chronic hepatitis and subsequent complications as liver cirrhosis and hepatocellular carcinoma, but also in a significant number of other diseases, the so-called extrahepatic manifestations of chronic HCV infection. In addition to lymphoproliferative and autoimmune disorders discussed in Part 1 of this review, many other diseases turned to be associated with chronic HCV infection. Part 2 of this review is dedicated to the analysis of the relationship of chronic HCV-infection to the development of some endocrine diseases, such as thyroiditis and diabetes mellitus, and cardiovascular disorders. It also provides the characteristics of the currently available antiviral agents and considers whether they may be used in patents with extrahepatic manifestations of chronic HCV infection.

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

AIM

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

METHODS

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

RESULTS

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

CONCLUSION

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

Retrospective study of the associations between hepatitis C virus infection and metabolic factors

AIM

To evaluate the bidirectional association between metabolic syndrome (MS) components and antiviral treatment response for chronic hepatitis C virus (HCV) infection.

METHODS

This retrospective cohort study included 119 HCV + patients treated with pegylated-interferon-α and ribavirin. Metabolic characteristics and laboratory data were collected from medical records. Differences in baseline clinical and demographic risk factors between responders and non-responders were assessed using independent samples t-tests or χ² tests. The effects of sustained viral response (SVR) to antiviral treatment on de novo impairments in MS components, including impaired fasting glucose (IFG) and type 2 diabetes mellitus (T2DM), were assessed using univariable and multivariable logistic regression analysis, while the effect of MS components on SVR was assessed using univariable logistic regression analysis.

RESULTS

Of the 119 patients, 80 (67%) developed SVR over the average 54 ± 13 mo follow-up. The cumulative risks for de novo T2DM and IFG were 5.07- (95%CI: 1.261-20.4, P = 0.022) and 3.87-fold higher (95%CI: 1.484-10.15, P = 0.006), respectively for non-responders than responders, when adjusted for the baseline risk factors age, sex, HCV genotype, high viral load, and steatosis. Post-treatment triglyceride levels were significantly lower in non-responders than in responders (OR = 0.27; 95%CI: 0.069-0.962, P = 0.044). Age and HCV genotype 3 were significantly different between responders and non-responders, and MS components were not significantly associated with SVR. Steatosis tended to attenuate SVR (OR = 0.596; 95%CI: 0.331-1.073, P = 0.08).

CONCLUSION

SVR was associated with lower de novo T2DM and IFG incidence and higher triglyceride levels. Patients infected with HCV should undergo T2DM screening and antidiabetic treatment.

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

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

Eradicating hepatitis C virus ameliorates insulin resistance without change in adipose depots

Chronic hepatitis C (CHC) is associated with lipid-related changes and insulin resistance; the latter predicts response to antiviral therapy, liver disease progression and the risk of diabetes. We sought to determine whether insulin sensitivity improves following CHC viral eradication after antiviral therapy and whether this is accompanied by changes in fat depots or adipokine levels. We compared 8 normoglycaemic men with CHC (genotype 1 or 3) before and at least 6 months post viral eradication and 15 hepatitis C antibody negative controls using an intravenous glucose tolerance test and two-step hyperinsulinaemic-euglycaemic clamp with [6,6-(2) H2 ] glucose to assess peripheral and hepatic insulin sensitivity. Magnetic resonance imaging and spectroscopy quantified abdominal fat compartments, liver and intramyocellular lipid. Peripheral insulin sensitivity improved (glucose infusion rate during high-dose insulin increased from 10.1 ± 1.6 to 12 ± 2.1 mg/kg/min/, P = 0.025), with no change in hepatic insulin response following successful viral eradication, without any accompanying change in muscle, liver or abdominal fat depots. There was corresponding improvement in incremental glycaemic response to intravenous glucose (pretreatment: 62.1 ± 8.3 vs post-treatment: 56.1 ± 8.5 mm, P = 0.008). Insulin sensitivity after viral clearance was comparable to matched controls without CHC. Post therapy, liver enzyme levels decreased but, interestingly, levels of glucagon, fatty acid-binding protein and lipocalin-2 remained elevated. Eradication of the hepatitis C virus improves insulin sensitivity without alteration in fat depots, adipokine or glucagon levels, consistent with a direct link of the virus with insulin resistance.

Interaction between hepatitis C virus and metabolic factors

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

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

BACKGROUND

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

AIM

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Impairment of health-related quality of life in patients with chronic hepatitis C is associated with insulin resistance

BACKGROUND

Although it has been reported that hepatitis C virus (HCV) infection is associated with a significant decline in health-related quality of life (HRQOL), the underlying causes and mechanisms are still unknown. Insulin resistance (IR) is recognized as a distinct aspect of chronic HCV infection. Therefore, we attempted to identify the factors including IR indices that are related to the HRQOL of patients with chronic hepatitis C (CHC).

METHODS

One hundred and seventy-five CHC patients (91 female, 84 male, mean age, 56.4 years) not using antidiabetic agents were included and underwent a 75-g oral glucose tolerance test (OGTT) and completed a self-administered HRQOL questionnaire, the Short Form 36 (SF-36), which is a well-validated questionnaire for assessing general QOL. Scale scores were standardized and summarized into physical and mental component summary (PCS and MCS). We investigated which clinical parameters, including homeostasis model assessment of insulin resistance (HOMA-IR), were associated with decline in PCS and MCS scores in CHC patients.

RESULTS

There were no significant differences in clinical parameters between high and low MCS, but there were significant differences in age, sex, hemoglobin, liver fibrosis, OGTT pattern, and HOMA-IR between high and low PCS. Multivariate analysis showed that HOMA-IR >2 was independently associated with lower PCS (OR 2.92, p < 0.01).

CONCLUSIONS

Our results suggest that impairment of HRQOL, especially physical domains, in CHC patients is associated with IR.

Association between phase angle, anthropometric measurements, and lipid profile in HCV-infected patients

OBJECTIVE

The objective of this study was to investigate the associations between phase angle, anthropometric measurements, and lipid profile in patients chronically infected with the hepatitis C virus.

METHODS

A total of 160 consecutive patients chronically infected with the hepatitis C virus and who received treatment at the hepatitis C outpatient unit of our hospital from April 2010 to May 2011 were prospectively evaluated. Bioelectrical impedance analysis, anthropometric measurements, and serum lipid profile analysis were performed.

RESULTS

Twenty-five patients were excluded. A total of 135 patients with a mean age of 49.8±11.4 years were studied. Among these patients, 60% were male. The phase angle and BMI means were 6.5±0.8° and 26.5±4.8 kg/m2, respectively. Regarding anthropometric variables, mid-arm circumference, mid-arm muscle circumference, and arm muscle area had a positive correlation with phase angle. In contrast, when analyzing the lipid profile, only HDL was inversely correlated with phase angle. However, in multiple regression models adjusted for age and gender, only mid-arm circumference (p = 0.005), mid-arm muscle circumference (p = 0.003), and arm muscle circumference (p = 0.001) were associated with phase angle in hepatitis C virus-infected patients.

CONCLUSIONS

In conclusion, phase angle is positively correlated with anthropometric measures in our study. However, there is no association between phase angle and lipid profile in these patients. Our results suggest that phase angle is related to lean body mass in patients chronically infected with hepatitis C virus.

Whole-body insulin resistance is associated with elevated serum α-fetoprotein levels in patients with chronic hepatitis C

OBJECTIVE

Little is known about the relationship between elevated serum α-fetoprotein (AFP) levels and insulin resistance, which adversely influence the clinical course of chronic hepatitis C (CHC). Therefore, we investigated the association between serum AFP and insulin resistance in patients with CHC.

METHODS

We retrospectively investigated 300 patients with CHC without hepatoma who underwent liver biopsies and oral glucose tolerance tests. Patients taking antidiabetic drugs were excluded. We analyzed factors associated with elevated AFP levels (≥ 10.0 ng/mL) in 265 eligible patients. Twenty patients with a homeostasis model assessment for insulin resistance value of ≥ 2.0 and a whole-body insulin sensitivity index of <5.0 received prospective lifestyle intervention.

RESULTS

A univariate analysis showed that the body mass index, platelet count, levels of albumin, aspartate aminotransferase, alanine aminotransferase and γ-glutamyl transpeptidase, glucose metabolism, hepatic inflammation, fibrosis and steatosis were associated with elevated AFP levels. In a multivariate analysis, a platelet count of < 15 × 10(4) /μL, aspartate aminotransferase level of ≥ 50 IU/L, γ-glutamyl transpeptidase level of ≥ 35 IU/L, whole-body insulin sensitivity index of <5.0 and stage 3-4 fibrosis were independently associated with an elevated AFP level. A Bayesian Network analysis showed that the aspartate aminotransferase level, whole-body insulin sensitivity index and hepatic fibrosis were directly associated with an elevated AFP level. The lifestyle intervention significantly improved the serum AFP level, homeostasis model assessment for insulin resistance and whole-body insulin sensitivity index.

CONCLUSION

Whole-body insulin resistance is associated with an elevated serum AFP level in patients with CHC. Lifestyle interventions targeting insulin resistance can reduce the serum AFP level and may ameliorate the clinical course of CHC.

Effects of interferon-alpha treatment on the incidence of hyperglycemia in chronic hepatitis C patients: a systematic review and meta-analysis

Background

There is a significant association between effects of interferon-alpha treatment and the risk of developing hyperglycemia in patients with chronic hepatitis C virus (HCV) infection. The objective of this systematic review and meta-analysis on the basis of published observational studies was to estimate risk of hyperglycemia in chronic HCV patients who had acquired sustained virological responses (SVR) compared to those without SVR.

Methodology

We identified eligible studies by searching the relevant databases, including PubMed, Embase, and Google, for papers published between January 1990 and April 2011. The selection of eligible papers was carried out using a scoring system based on guidelines and inclusion criteria that were established before the articles were identified. Heterogeneity across studies was determined and the meta-analysis was performed following standard guidelines.

Conclusions

Eleven eligible studies provided data of the incidence of hyperglycemia in chronic hepatitis C patients with SVR in comparison with patients without these conditions. The results demonstrated that SVR was associated with a lower risk of hyperglycemia (odds ratio = 0.497, 95% confidence interval 0.421–0.587, p<0.001), and there was no evidence of any substantial between-study heterogeneity (I² = 24.4%, p>0.1). Results of meta-regression showed patients with different baseline glucose (normal vs. abnormal) and patients with co-infected HIV (presence vs. absence) as the sources of low heterogeneity (p<0.15).The lowest risk of hyperglycemia was described in patients with normal glucose baseline (OR = 0.402, 95%CI 0.297–0.543, p<0.001). This is the first systematic review and meta-analysis performed to examine the association between SVR and risk of hyperglycemia in patients with HCV infection. Our meta-analysis suggests that SVR reduce the risk of developing glucose abnormalities, especially in patients with normal glucose baseline.

Impact of insulin resistance on HCV treatment response and impact of HCV treatment on insulin sensitivity using direct measurements of insulin action

OBJECTIVE

Insulin resistance, as measured by surrogate markers, is associated with lower response to hepatitis C virus (HCV) therapy and may improve with HCV eradication. We prospectively evaluated the impact of directly measured insulin resistance and abnormal glucose metabolism on achieving sustained virologic response (SVR) with HCV therapy and assessed whether SVR results in improved insulin sensitivity and fasting glucose.

RESEARCH DESIGN AND METHODS

A total of 50 noncirrhotic, nondiabetic, HCV-infected patients (27 untreated, 23 treated with pegylated interferon/ribavirin, nonrandomized) underwent clinical and histologic evaluation and 75-g oral glucose tolerance test. Insulin sensitivity was assessed directly with insulin suppression test by measuring steady-state plasma glucose (SSPG) concentration during a 240-min infusion of octreotide, glucose, and insulin. Of the subjects, 43 had at least one follow-up evaluation.

RESULTS

Patient characteristics were median age 48, 57% male, and 52% white. SVR was achieved in 61% (14 of 23) of treated subjects. SVR was independently associated with HCV genotypes 2 and 3 (odds ratio 8.8 [95% CI 1.2-61.7]) but was not strongly associated with insulin sensitivity. When controlling for elapsed time between measurements, being on interferon, and BMI, SSPG decreased by 36 mg/dL (-88 to 16) in those with SVR and decreased by 28 mg/dL (-93 to 38) in those without SVR, compared with the untreated group. BMI (coefficient 9.1 per 5 units; 95% CI 5.3-12.9) and interferon use (coefficient 56; 95% CI 6.8-105) were associated with SSPG.

CONCLUSIONS

Insulin resistance does not appear to be strongly associated with SVR. HCV therapy may improve insulin resistance regardless of virologic response; however, BMI and interferon use were clearly associated with insulin resistance.

Impact of insulin resistance on sustained response in HCV patients treated with pegylated interferon and ribavirin: a meta-analysis

BACKGROUND & AIMS

Recent studies suggested that SVR rates might be lower in HCV patients with insulin resistance (IR) than in patients without IR, but the extent of the impact of IR on treatment response has not been established. We aimed to confirm the role of IR assessed by the homoeostasis model assessment (HOMA-IR) on SVR and to determine its magnitude.

METHODS

We performed meta-analysis of studies evaluating the impact of IR in HCV patients treated with pegylated interferon and ribavirin.

RESULTS

Fourteen studies involving 2732 patients were included. SVR was less frequent in patients with IR than in patients without IR (mean difference: -19.6%, 95% CI: -29.9% to -9.4%, p<0.001). In sensitivity analyses according to HCV-1 patients, patients with IR also less frequently attained a SVR than patients without IR (mean difference: -13.0%, 95% CI: -22.6% to -3.4%, p=0.008). In addition, the baseline HOMA-IR index was lower in responders than in non-responders (mean difference: -0.92, 95% CI: -1.53 to -0.32, p<0.001). In sensitivity analyses restricted to HCV-1 patients, the baseline HOMA-IR index remained lower in responders than in non-responders (mean difference: -0.63, 95% CI: -1.13 to -0.14, p<0.001).

CONCLUSIONS

HCV patients with IR have a 20% lower SVR than patients without IR. The baseline HOMA-IR index is a major determinant of SVR.

Post-challenge hyperglycemia is a significant risk factor for the development of hepatocellular carcinoma in patients with chronic hepatitis C

BACKGROUND

Several epidemiological studies have reported that diabetes mellitus is a risk factor for hepatocellular carcinoma (HCC) in hepatitis C virus (HCV)-positive patients. However, it is unclear whether or not post-challenge hyperglycemia is a risk factor. The purpose of this study was to determine the association between post-challenge hyperglycemia and hepatocarcinogenesis in HCV-positive patients.

METHODS

A total of 203 HCV-RNA-positive subjects (108 males, mean age 54.3 ± 10.8 years; 95 females, mean age 56.6 ± 10.3 years; genotype 1b/2a/2b/3a: 152/38/12/1) who underwent liver biopsy and a 75-g oral glucose tolerance test, and who were treated with interferon (IFN) were enrolled in this study. None of the subjects had been treated with antidiabetic drugs. The subjects underwent ultrasonography and/or computed tomography every 6 months after the end of the IFN therapy.

RESULTS

Thirteen patients, including one patient who achieved a sustained viral response (SVR) with IFN, developed HCC. On multivariate analysis, male sex, age >65 years, excessive alcohol consumption, non-SVR, liver steatosis area >5% in liver specimens, and 120-min post-challenge hyperglycemia were risk factors for the development of HCC. After matching subjects for sex, age, alcohol intake, and response to the IFN therapy, advanced fibrosis stages [hazard ratio (HR) 2.8], liver steatosis (HR 5.4), and 120-min post-challenge hyperglycemia (HR 4.9) were significant risk factors for the development of HCC. Furthermore, after matching for the fibrosis stage, liver steatosis (HR 5.7) and 120-min post-challenge hyperglycemia (HR 6.9) remained as significant factors for HCC development.

CONCLUSION

Post-challenge hyperglycemia is an independent risk factor for HCC in HCV-positive patients.

Insulin resistance and chronic liver disease

Increased insulin resistance is frequently associated with chronic liver disease and is a pathophysiological feature of hepatogenous diabetes. Distinctive factors including hepatic parenchymal cell damage, portal-systemic shunting and hepatitis C virus are responsible for the development of hepatogenous insulin resistance/diabetes. Although it remains unclear whether insulin secretion from pancreatic beta cells is impaired as it is in type 2 diabetes, retinopathic and cardiovascular risk is low and major causes of death in cirrhotic patients with diabetes are liver failure, hepatocellular carcinoma and gastrointestinal hemorrhage. Hemoglobin A1c is an inaccurate marker for the assessment and management of hepatogenous diabetes. Moreover, exogenous insulin or sulfonylureas may be harmful because these agents may promote hepatocarcinogenesis. Thus, pathogenesis, cause of death, assessment and therapeutic strategy for hepatogenous insulin resistance/diabetes differ from those for lifestyle-related type 2 diabetes. In this article, we review features of insulin resistance in relationship to chronic liver disease. We also discuss the impact of anti-diabetic agents on interferon treatment and hepatocarcinogenesis.

Metabolic factors are associated with serum alanine aminotransferase levels in patients with chronic hepatitis C

BACKGROUND

Although serum alanine aminotransferase (ALT) activity is an important marker for the management of chronic hepatitis C (CHC), the factors associated with serum ALT levels remain to be fully understood. This study aimed to clarify the association between serum ALT levels and clinical, histological, and virological factors in patients with CHC.

METHODS

We retrospectively analyzed 256 patients with CHC who underwent liver biopsy, and classified them into three groups according to serum ALT levels: normal to minimal (<40 IU/L), mild (40-80 IU/L), and moderate to severe elevation (≥80 IU/L). All demographic and laboratory data were collected at the time of liver biopsy. All biopsies were evaluated for fibrosis, inflammation, and steatosis. Glucose metabolism was assessed by various indices derived from oral glucose tolerance tests, including the homeostasis model assessment for insulin resistance (HOMA-IR). In 180 patients, visceral fat area was measured at the umbilical level by abdominal computed tomography.

RESULTS

Ordered logistic regression analysis showed that higher serum ALT levels were significantly associated with male sex, lower high-density lipoprotein cholesterol (HDL-C), higher HOMA-IR, and higher grades of histological inflammation and steatosis. HOMA-IR, HDL-C, and hepatic steatosis were associated with visceral fat accumulation.

CONCLUSIONS

Metabolic factors, as well as sex and hepatic inflammation, are independent risk factors for serum ALT elevation in hepatitis C virus (HCV)-infected patients. Metabolic factors may offer targets to decrease serum ALT levels.

Importance of hepatitis C virus-associated insulin resistance: Therapeutic strategies for insulin sensitization

Insulin resistance is one of the pathological features in patients with hepatitis C virus (HCV) infection. Generally, persistence of insulin resistance leads to an increase in the risk of life-threatening complications such as cardiovascular diseases. However, these complications are not major causes of death in patients with HCV-associated insulin resistance. Indeed, insulin resistance plays a crucial role in the development of various complications and events associated with HCV infection. Mounting evidence indicates that HCV-associated insulin resistance may cause (1) hepatic steatosis; (2) resistance to anti-viral treatment; (3) hepatic fibrosis and esophageal varices; (4) hepatocarcinogenesis and proliferation of hepatocellular carcinoma; and (5) extrahepatic manifestations. Thus, HCV-associated insulin resistance is a therapeutic target at any stage of HCV infection. Although the risk of insulin resistance in HCV-infected patients has been documented, therapeutic guidelines for preventing the distinctive complications of HCV-associated insulin resistance have not yet been established. In addition, mechanisms for the development of HCV-associated insulin resistance differ from lifestyle-associated insulin resistance. In order to ameliorate HCV-associated insulin resistance and its complications, the efficacy of the following interventions is discussed: a late evening snack, coffee consumption, dietary iron restriction, phlebotomy, and zinc supplements. Little is known regarding the effect of anti-diabetic agents on HCV infection, however, a possible association between use of exogenous insulin or a sulfonylurea agent and the development of HCC has recently been reported. On the other hand, insulin-sensitizing agents are reported to improve sustained virologic response rates. In this review, we summarize distinctive complications of, and therapeutic strategies for, HCV-associated insulin resistance. Furthermore, we discuss supplementation with branched-chain amino acids as a unique insulin-sensitizing strategy for patients with HCV-associated insulin resistance.

Age-related fat deposition in multifidus muscle could be a marker for nonalcoholic fatty liver disease

BACKGROUND

Although nonalcoholic fatty liver disease (NAFLD) is associated with visceral obesity, the relationship between visceral fat accumulation and skeletal muscle steatosis in patients with NAFLD has not been established. We evaluated: (1) the relationship between multifidus muscular tissue steatosis, visceral fat accumulation, and biochemical data in a cross-sectional study, and (2) the influence of weight reduction on multifidus muscular tissue steatosis in a longitudinal study.

METHODS

Three hundred thirty-three NAFLD patients were enrolled. Hepatic steatosis, visceral fat area, and the multifidus muscle/subcutaneous fat attenuation ratio (MM/F ratio) were evaluated by computed tomography. To evaluate how weight reduction produced by diet and exercise affected the MM/F ratio, changes in the MM/F ratio were compared between weight reduction and non-weight reduction groups.

RESULTS

There was a gender difference in MM/F ratios. The MM/F ratio was significantly correlated with age (male r = 0.613, P < 0.01; female r = 0.440, P < 0.01). The MM/F ratio was positively correlated with visceral fat area (male: r = 0.262, P < 0.01; female: r = 0.214, P < 0.01). A decrease in the MM/F ratio, concomitant with reduced visceral fat accumulation, led to alleviation of hepatic steatosis in 20 patients with weight reduction, but not in 22 patients without weight reduction.

CONCLUSIONS

The MM/F ratio was closely related to aging and visceral fat accumulation. The MM/F ratio was improved by weight reduction, indicating that fat accumulation in the multifidus muscle evaluated by computed tomography might be a therapeutic indicator of NAFLD.