Hepatitis C and Alcohol : Treatment Issues

by National Institute of Health

(Page 3 of 3)

Heavy alcohol use can be detrimental to HCV-infected patients' long-term response to interferon therapy. It is likely that alcohol affects HCV treatment effectiveness both because drinking tends to interfere with patients' adherence to therapy and because alcohol interferes with interferon therapy's antiviral actions.

Hepatitis C Infection: Disease Characteristics, Testing, and Treatment

The symptoms and course of hepatitis C vary greatly. Many people who are infected with the virus show no symptoms (although they can still infect others), whereas some people may experience fatigue, weakness, fever, nausea, abdominal pain, poor appetite, muscle and joint pain, or yellowing of the skin and eyes (jaundice). About 75 percent of patients who are infected with HCV develop chronic infection. Between 10 and 40 percent of HCV patients develop cirrhosis (a condition in which normal liver cells are replaced by scar tissue) within 20 to 40 years, and 1 to 3 percent develop liver cancer.

Many patients who develop cirrhosis show no symptoms of the disease and can expect long-term survival. Data from a cohort of European patients with cirrhosis followed for an average of 5 years showed that only 7 percent developed hepatocellular carcinoma, and 18 percent experienced symptomatic liver failure. There currently is no vaccine for hepatitis C.

Testing and Treatment

Blood tests can diagnose HCV infection, either by detecting antibodies to the virus or by detecting the presence and quantity of the virus's genetic material itself. Liver biopsy is quite helpful for evaluating the disease's severity prior to initiating treatment. Liver enzymes have little value in predicting fibrosis.

There are six known genetic variants (genotypes) of HCV, which vary geographically in their rate of occurrence. Genotypes 1, 2, and 3 constitute the majority of genotypes in the United States.

The standard treatment for symptomatic hepatitis C infection is a combination of the drugs pegylated interferon (peginterferon) and ribavirin. Strict abstinence from alcohol is important during treatment.

Currently, the best indicator of effective treatment is a sustained virological response, defined by the absence of detectable virus 24 weeks after the end of treatment. Early viral response is predictive of SVR, and patients who fail to achieve an early viral response at week 12 should discontinue the treatment. Genotype 1 requires 1 year of treatment, whereas genotypes 2 and 3 require a 6-month course. In research with patients who did not consume alcohol during the therapy, SVR rates of 42 to 46 percent for genotype 1 and 76 to 82 percent for genotypes 2 and 3 have been obtained.

Abstention Before Interferon Treatment

Some research has indicated that heavy drinkers who abstain from alcohol before interferon treatment respond better to treatment than do those who continue to drink. In one study, heavy drinkers who did not abstain from drinking before interferon treatment showed a total lack of HCV RNA clearance, whereas those who normally drank heavily but abstained from drinking before interferon treatment showed some improvement in HCV RNA clearance (and the virus completely disappeared in 15.8 percent of heavy drinkers who abstained before treatment).

However, this study indicated that when HCV-infected alcoholic patients who normally drank heavily (70 or more grams of alcohol, or at least 5.8 drinks, per day) abstained from alcohol consumption during interferon therapy, their rate of HCV RNA clearance was markedly lower than was the case for HCV-infected nondrinkers. These results were confirmed by a recent Italian study in which 150 patients with chronic HCV underwent interferon treatment for 1 year after 6 months of abstinence from alcohol. (Abstinence was verified by analyzing blood levels of a biological marker of heavy alcohol consumption known as carbohydrate-deficient transferrin.) Although all patients had abstained from alcohol before beginning treatment, only 9 percent of heavy drinkers exhibited a sustained response to the interferon treatment, compared with 20 percent of light drinkers and 33 percent of nondrinkers. The factors that most strongly predicted a poor response to interferon treatment were the specific type of HCV infection, patients' age, and their lifetime alcohol intake.

Treatment Recommendations

The evidence is strong that continued heavy alcohol intake during interferon treatment adversely affects treatment effectiveness. Further, depression, irritability, and anxiety - side effects that occur in 20 to 30 percent of patients who receive interferon treatment - may be especially difficult to manage for patients with a history of alcoholism, predisposing them to begin drinking again. Despite this risk, however, the data do not support withholding interferon therapy for chronic HCV from patients with a history of alcoholism or heavy drinking if they remain abstinent and have adequate psychosocial support during treatment. Likewise, light-to-moderate drinkers should not be excluded from HCV treatment, nor should a period of abstinence before starting therapy be enforced in this patient population.

Summary

Excessive alcohol consumption among patients infected with chronic hepatitis C is likely to result in more severe liver injury, promoting cirrhosis and increasing the risk for development of liver cancer (specifically, hepatocellular carcinoma). Although the mechanisms by which chronic hepatitis C progresses to more severe liver disease in alcoholic patients have not been clearly established, they may include an alcohol-induced increase in viral replication; rapid mutation of HCV, leading to greater viral complexity; increased liver-cell death and inflammatory response; suppression of immune responses; accumulation of fat in the liver; and accumulation of excess iron in body tissues.

In addition to greatly heightening HCV-infected patients' risk of serious liver disease, heavy drinking during antiviral (interferon) treatment has been shown to impede patients' responses to therapy. Abstaining from drinking before and during treatment improves patients' response to antiviral therapy, although this improvement is not total. In light of these findings, alcoholic patients should be advised to abstain from further alcohol consumption and should be alcohol free for at least 6 months before beginning interferon therapy.

Future research should further examine the effects of light and moderate drinking on features of the hepatitis C virus; alcohol's effect on virus activity and response to treatment; patients' immune responses to the virus; mechanisms of fibrosis in response to HCV infection and alcohol use; and animal models of HCV infection that may shed greater light on disease processes in humans.

About the Author

NIH is the nation's medical research agency - making important medical discoveries that improve health and save lives. The National Institutes of Health (NIH), a part of the U.S. Department of Health and Human Services, is the primary Federal agency for conducting and supporting medical research.