Chronic Hepatitis C Virus Infection Is Associated with Early Atherosclerosis

SUMMARY: People with chronic hepatitis C are more likely than those never infected to have diabetes and visceral fat accumulation, but have lower levels of LDL "bad" cholesterol, according to a study described in the June 28, 2010 advance online issue of Gut. After HCV clearance, LDL levels rose to match those of never-infected individuals, but glucose levels and abdominal fat remained similar. After adjusting for other risk factors, chronic hepatitis C patients had greater carotid intima-media thickness, an indicator of the early stages of atherosclerosis.

By Liz Highleyman

Previous research has found that people with chronic hepatitis C virus (HCV) infection have an elevated risk for cardiovascular disease. While HCV has been linked to insulin resistance or diabetes -- known risk factors for heart disease -- it is also typically characterized by favorable blood lipid levels.

In the present study, Aya Mostafa from AinShams University in Cairo and colleagues looked at the effect of this paradoxical risk profile on metabolism and atherosclerosis (hardening of the arteries and build-up of plaque) in the setting of HCV infection and clearance.

This cross-sectional analysis included more than 1200 participants in Egypt aged 35 years or older. Within this study population, 329 had chronic hepatitis C, 173 had cleared HCV infection, and 795 were never infected with HCV; a subset of 192, 115, and 187 participants, respectively, from the 3 groups underwent ultrasound imaging.

The investigators evaluated presence of diabetes, fasting blood glucose, lipid levels, and body fat deposition using ultrasound. Carotid intima-media thickness (IMT), or width of the inner lining of the carotid arteries supplying the brain, was used as a measure of atherosclerosis.

Results

• Diabetes was more common among participants with chronic hepatitis C and cleared HCV infection (both with a prevalence of 10.1%) than among those who never had HCV (6.6%; P = 0.04 for chronic, 0.08 for cleared).
• The amount of mesenteric or visceral fat was greater in people with chronic hepatitis C (36.4 mm) and cleared infection (37.8 mm) relative to those never infected (32.7 mm; P = 0.004 for chronic, < 0.0001 for cleared).
• Low-density lipoprotein (LDL) cholesterol levels were lower in the chronic hepatitis C group (2.69 mmol/L; P < 0.001), but similar in those with cleared infection (3.56 mmol/L; P = 0.4) and those never infected (3.45 mmol/L).
• Carotid IMT did not differ significantly according to HCV infection status, at 0.73, 0.71, and 0.71 mm, respectively.
• After adjustmenting for traditional cardiovascular risk factors, however, IMT was greater in peoplewith chronic infection (0.76 mm) compared with never infected individuals (0.70 mm; P = 0.02).

Based on these findings, the researchers proposed, "Hepatic function normalization with HCV clearance may account for reversal of favorable lipids observed with HCV infection." However, they added, glucose levels and visceral fat accumulation "appear less amenable to HCV resolution."

"These different cardiovascular risk patterns may determine equivalent atherosclerosis risk by infection status," they suggested. "However, once these factors were accounted for, those with chronic infection had raised IMT, suggesting a direct effect of infection."

Department of Community Medicine, Faculty of Medicine, AinShams University, Cairo, Egypt; Department of Tropical Medicine, Faculty of Medicine, Cairo University, Cairo, Egypt; Viral Hepatitis Reference Laboratory, National Hepatology and Tropical Medicine Research Institute, Cairo, Egypt; Institut Pasteur, Paris, France; Department of Metabolic Medicine, Imperial College NHS Healthcare Trust, London, UK; International Centre for Circulatory Health, National Heart & Lung Institute, Imperial College NHS Healthcare Trust, London, UK; Faculty of Medicine, Minia University, Minia, Egypt.

7/30/10

Reference

A Mostafa, MK Mohamed, M Saeed, and others. Hepatitis C infection and clearance: impact on atherosclerosis and cardiometabolic risk factors. Gut (Abstract). June 28, 2010 (Epub ahead of print).

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