Epidemiology

Inactive hepatitis B virus can still cause liver cancer

Last Updated: 2010-02-15 13:00:17 -0400 (Reuters Health)

NEW YORK (Reuters Health) - Despite a belief by researchers that inactive carriers of hepatitis B virus (HBV) are not at high risk of disease progression, a new study suggests that such patients are still at increased risk of hepatocellular carcinoma (HCC) and liver-related death.

And a drinking habit is "the universal risk predictor of liver disease progression" in such patients, note Dr. Chien-Jen Chen and co-authors in the January 28 online issue of Gastroenterology.

Inactive HBV carriers have hepatitis B surface antigen in serum without hepatitis B e antigen or aminotransferase elevations, according to the authors. These patients have HBV DNA levels < 10,000 copies/mL.

In a prospective cohort study conducted in Taiwan, the researchers compared the risk of HCC and liver-related mortality in two subcohorts from the REVEAL-HBV study: an inactive HBV carrier group (n = 1932) and a control group negative for hepatitis B surface antigen and antibody against hepatitis C virus (n = 18,137).

They excluded people with liver cirrhosis at entry or who developed end-stage liver disease during the first 12 months. Subjects' ages ranged from 30-65, and none received antiviral medications.

Dr. Chen, from Academia Sinica, Taipei, and his group believe this is the first population-based study with long-term follow-up (mean 13.1 years) of inactive HBV carriers.

They verified liver-related death and new cases of hepatocellular carcinoma through computerized data linkage with the National Cancer Registry and National Death Certification files.

Among inactive HBV carriers, the incidence rate of hepatocellular carcinoma was 64 per 100,000 person-years, compared to 15 for controls (p < 0.001, adjusted hazard ratio 4.6).

Corresponding rates of liver-related death were 44 per 100,000 person-years among inactive carriers, and 21 per 100,000 person-years in the control group (p = 0.029; adjusted HR 2.1).

Older age and drinking alcohol at least 4 days per week for at least 1 year both predicted liver cancer and liver-related death among carriers.

The presence of hepatocellular carcinoma increased liver-related mortality risk more than 400-fold.

Even carriers with an undetectable serum HBV DNA level at study entry were at increased risk for both liver cancer and cancer-related death.

One weakness of the study, the authors note, is that it was not clear how many subjects remained in the inactive carrier phase because there were neither liver biopsies nor serial HBV DNA levels available.

Gastroenterology 2010.