Fat accumulation in the liver was not only linked to a higher likelihood of fibrosis progression but also to a threefold bump in the odds of hepatitis B surface antigen (HBsAg) seroclearance in people with inactive chronic hepatitis B, according to study results published in the Journal of Hepatology.
Non-alcoholic fatty liver disease (NAFLD) frequently accompanies chronic hepatitis B, but its effect on liver-related outcomes is not well understood. Fatty liver disease and hep B both independently increase the risk of cirrhosis and liver cancer. Chronic hepatitis B can be treated with antivirals, but it is seldom cured.
Lung-Yi Mak, MBBS, of the University of Hong Kong, and colleagues explored the impact of fat accumulation in the liver on the risk of developing fibrosis and HBsAg seroclearance. The loss of HBsAg and related antibodies in people with chronic hepatitis B is considered a functional cure.
The team recruited individuals with chronic hepatitis B virus (HBV) infection who had normal ALT liver enzyme levels and low hepatitis B viral load in their blood. They had not yet received antiviral therapy, which is generally not recommended for people with inactive hepatitis B. The 330 participants had a median age of 51 years, and 59% were women.
These participants underwent transient elastography (FibroScan) twice—at the time of recruitment and after three years—to assess the extent of liver fibrosis. In addition to liver stiffness measurements, the researchers also determined the controlled attenuation parameter (CAP) score, which measures the intensity of sound waves as they travel through fatty tissue compared with normal liver tissue.
At the beginning of the study, 49% of participants had fat accumulation in the liver, including 29% with severe steatosis. At study initiation, 4.2% had advanced liver fibrosis or cirrhosis; this increased to 8.7% after three years. Overall, fibrosis progression was seen in 25% of the participants even with inactive HBV.
Liver fibrosis was more common in people with persistent severe liver fat accumulation (41%) compared with those who had a recent onset (35%) or those without fat buildup (23%). Further, continual severe fat accumulation in the liver was independently linked to the advancement of fibrosis.
Twenty-two participants (6.7%) attained HBsAg seroclearance over the course of the study. Fat buildup in the liver was linked to a threefold higher likelihood of seroclearance.
Individuals with liver fat accumulation and a low HBV viral load had a 18% chance of achieving HBsAg seroclearance. For those with just one of these factors, the likelihood of seroclearance was 3.3%. People without fat buildup and a higher viral load had only a 1.1% chance of attaining seroclearance.
“Routine CAP measurement in apparently low-risk [chronic hepatitis B] patients carries prognostic value for subsequent HBsAg seroclearance and fibrosis progression,” wrote the researchers.
“Coexisting fatty liver disease in patients with chronic viral hepatitis B infection leads to worsening liver fibrosis but also increases the chance of cure from hepatitis B virus,” they added. “Routine bedside assessment of liver fat content is important for risk assessment in treatment-naive patients with chronic hepatitis B.”
Click here to read the study abstract in the Journal of Hepatology.