Cardiovascular disease in cirrhosis--a point-prevalence study in relation to glucose tolerance

Hepatitis C virus and metabolic disorder interactions towards liver damage and atherosclerosis

Hepatitis C virus (HCV) is one of the main causes of liver disease worldwide, and alterations of glucose metabolism have reached pandemic proportions in western countries. However, the frequent coexistence between these two conditions is more than simply coincidental, since HCV can induce insulin resistance through several mechanisms. Indeed, the virus interferes with insulin signaling both directly and indirectly, inducing the production of pro-inflammatory cytokines. Furthermore, the entire viral life cycle has strict interconnections with lipid metabolism, and HCV is responsible for a “viral” steatosis which is frequently superimposed to a “metabolic” one. Several evidences suggest that HCV-induced metabolic disorders contribute both to the evolution of liver fibrosis and, likely, to the progression of the other disorders which are typically associated with altered metabolism, in particular atherosclerosis. In the present review, we will examine in depth the links between HCV infection and insulin resistance, liver steatosis and diabetes, and analyze the impact of these interactions on the progression of liver fibrosis and atherosclerosis. Special attention will be focused on the highly debated topic of the relationship between HCV infection and cardiovascular disease. The available clinical literature on this item will be broadly reviewed and all the mechanisms possibly implied will be discussed.

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.

Systemic abnormalities in liver disease

Systemic abnormalities often occur in patients with liver disease. In particular, cardiopulmonary or renal diseases accompanied by advanced liver disease can be serious and may determine the quality of life and prognosis of patients. Therefore, both hepatologists and non-hepatologists should pay attention to such abnormalities in the management of patients with liver diseases.

Hepatic steatosis is associated with an increased risk of carotid atherosclerosis

AIM: Although an association between hepatic steatosis and vascular risk factors has been described, direct relationships between fatty liver and atherosclerosis have not yet been investigated. The aim of the present study has been to investigate those relationships.

METHODS: The Study of Health in Pomerania examined a random population sample aged between 20 and 79 years. A study population of 4222 subjects without hepatitis B and C infections and without liver cirrhosis was available for the present analysis. Hepatic steatosis was defined sonographically and intima-media thickness (IMT) as well as plaque prevalence were estimated by carotid ultrasound.

RESULTS: The prevalence rate of hepatic steatosis was 29.9%. Among subjects aged ≥45 years, an association between hepatic steatosis and IMT of the carotid arteries was found in bivariate analysis, but not after adjustment for atherosclerotic risk factors. Individuals with fatty liver had more often carotid plaques than persons without fatty liver (plaque prevalence rate 76.8% vs 66.6%; P<0.001). This association persisted after adjustment for confounding factors and was predominantly present in subjects with no to mild alcohol consumption.

CONCLUSION: There is an independent association between hepatic steatosis and carotid atherosclerotic plaques. Metabolic changes due to nonalcoholic fatty liver disease may explain this relationship.

Hepatitis B virus infection and coronary atherosclerosis: Results from a population with relatively high prevalence of hepatitis B virus

AIM: To investigate the possible association between hepatitis B virus (HBV) infection and angiographically proven coronary artery disease (CAD) in a population with relatively high prevalence of HBV.

METHODS: Sera from 434 patients who underwent coronary angiography were tested for HBV antigens (HBsAg, HBeAg) and antibodies (Anti-HBs, Anti-HBc and Anti-HBe) by ELISA.

RESULTS: Seventy-seven percent (224/291) of the patients with CAD and 73.4% (105/143) of the patients without angiographic evidence of atherosclerosis were seropositive for HBV (P>0.05). However, C-reactive protein (CRP) levels were significantly higher in patients with CAD (P = 0.008), while lower in HBV seropositive population (P = 0.043 and P = 0.021 after adjustment for conventional risk factors).

CONCLUSION: Our results suggested HBV infection negatively correlates with CRP levels, but seems not to be associated with coronary atherosclerosis.

Prevalence and determinants of diabetes mellitus among Iranian patients with chronic liver disease

BACKGROUND: Alterations in carbohydrate metabolism are frequently observed in cirrhosis. We conducted this study to define the prevalence of diabetes mellitus (DM) and impaired glucose tolerance (IGT) in Iranian patients with chronic liver disease (CLD), and explore the factors associated with DM in these patients. METHODS: One hundred and eighty-five patients with CLD were enrolled into the study. Fasting plasma glucose and two-hour plasma glucose were measured in patients' sera. DM and IGT were diagnosed according to the latest American Diabetes Association criteria. RESULTS: The subjects included 42 inactive HBV carriers with a mean age of 42.2 +/- 12.0 years, 102 patients with HBV or HCV chronic hepatitis with a mean age of 41.2 +/- 10.9 years, and 41 cirrhotic patients with a mean age of 52.1 +/- 11.4 years. DM and IGT were diagnosed in 40 (21.6%) and 21 (11.4%) patients, respectively. Univariate analysis showed that age (P = 0.000), CLD status (P = 0.000), history of hypertension (P = 0.007), family history of DM (P = 0.000), and body mass index (BMI) (P = 0.009) were associated with DM. Using Multivariate analysis, age (OR = 4.7, 95%CI: 1.8-12.2), family history of DM (OR = 6.6, 95%CI: 2.6-17.6), chronic hepatitis (OR = 11.6, 95%CI: 2.9-45.4), and cirrhosis (OR = 6.5, 95%CI: 2.4-17.4) remained as the factors independently associated with DM. When patients with cirrhosis and chronic hepatitis were analyzed separately, higher Child-Pugh's score in cirrhotic patients (OR = 9.6, 95%CI: 1.0-88.4) and older age (OR = 7.2, 95%CI: 1.0-49.1), higher fibrosis score (OR = 59.5, 95%CI: 2.9-1211.3/ OR = 11.9, 95%CI: 1.0-132.2), and higher BMI (OR = 30.3, 95%CI: 3.0-306.7) in patients with chronic hepatitis were found to be associated with higher prevalence of DM. CONCLUSIONS: Our findings indicate that patients with cirrhosis and chronic hepatitis are at the increased risk of DM occurrence. Older age, severe liver disease, and obesity were associated with DM in these patients.

Differential mechanism and prognostic impact of diabetes mellitus on patients with hepatocellular carcinoma undergoing surgical and nonsurgical treatment

OBJECTIVES

Diabetes mellitus (DM) is prevalent in patients with hepatocellular carcinoma (HCC) due to coexisting cirrhosis. This study aimed to investigate the long-term impact of DM on HCC patients and its underlying mechanism.

METHODS

A total of 567 (120 diabetic) HCC patients were included. The survival was compared between patients with and without DM according to the treatment modality. The occurrence of hepatic decompensation was defined as the sustained increment of the Child-Pugh score by 2 points or more during the follow-up period.

RESULTS

Survival analysis showed that DM was not a significant prognostic predictor among the 255 (41 diabetic, 16%) patients who underwent resection (p= 0.155). However, DM was a poor prognostic predictor among those with small (< or = 5 cm) HCC (n = 159; relative risk [RR]: 2.3, 95% confidence interval [CI]: 1.2-5.1, p= 0.021) or those without postoperative tumor recurrence (n = 133; RR: 2.1, 95% CI: 1.2-4.8, p= 0.032) due to the occurrence of more diabetes-related deaths. Of the 312 (79 diabetic, 25%) patients who underwent nonsurgical treatment including transarterial chemoembolization and percutaneous injection, DM was a poor prognostic predictor among those with Child-Pugh A reserve (n = 222; RR: 1.6, 95% CI: 1.1-2.5, p= 0.044). Diabetic patients were more susceptible to develop hepatic decompensation in this group (RR: 1.7, 95% CI: 1.1-2.6, p= 0.012).

CONCLUSIONS

There is a selective mechanism and prognostic impact of DM on HCC patients undergoing surgical and nonsurgical therapy. DM may affect the long-term survival through diabetes-related complications or inducing liver failure depending on treatment strategy and under the influence of tumoral and cirrhosis factors.

Diabetes mellitus is a risk factor for hepatic decompensation in patients with hepatocellular carcinoma undergoing resection: a longitudinal study

OBJECTIVES

Patients with hepatocellular carcinoma (HCC) frequently have diabetes mellitus (DM) due to coexisting liver cirrhosis. The aim of this study was to assess the long-term impact of DM on the hepatic regenerative ability of HCC patients undergoing surgical resection.

METHODS

We retrospectively studied 245 HCC patients (210 male; age, 61 +/- 13 yr) with well-preserved liver functions undergoing resection. Forty (16%) of them were diabetic and were controlled with hypoglycemic agents. The Child-Pugh scoring system was used to evaluate the postoperative liver regeneration ability. The endpoint was the occurrence of hepatic decompensation, defined as a sustained increase in the Child-Pugh score of 2 or more points or the development of tumor recurrence.

RESULTS

Seventy-five patients (31%) developed hepatic decompensation during a follow-up period of 27 +/- 18 months (range, 3-75). DM (p = 0.001), large (>3 cm) tumor size (p = 0.044), and age > 65 yr (p = 0.058) were the factors associated with hepatic decompensation in univariate analysis. Multivariate Cox regression model analysis confirmed that DM (relative risk [RR] = 2.3, 95% CI = 1.4-3.7, p = 0.001) and tumor size > 3 cm (RR = 1.7, 95% CI = 1.1-2.7, p = 0.046) were independent prognostic predictors associated with the occurrence of hepatic decompensation; the respective 3- and 5-yr cumulative rates were 53% and 64% versus 27% and 50% for diabetic and nondiabetic patients, and 24% and 41% versus 38% and 60% for patients with small (< or =3 cm) versus large (>3 cm) tumors.

CONCLUSION

HCC patients with DM or large tumor size are at a cumulative increased risk for postoperative hepatic decompensation.