Coinfection with hepatitis B and C virus (HBV/HCV) combined with risky alcohol consumption enhances liver damage mechanisms to a greater extent in women than in men, according to a recent study in PLoS One.
Hepatitis infection and risky drinking are major risk factors for liver disease, and coinfection with both HBV and HCV is more likely to progress to cirrhosis than single infections. Pooled data from 2 national surveys in Italy allowed the estimation of interactions among alcohol intake, HBV infection, and HCV infection on cirrhosis risk by gender.
Data from 12,262 patients were collected in either 2001 or 2014. Interactions among the 3 risk factors were assessed with crude odds ratios (OR) adjusted for age and body mass index. Interactions among alcohol intake, HBV, and HCV were assessed as additive or multiplicative. Interactions were additive when the observed joint effect of 2 or more factors on cirrhosis exceeded the sum of the effect of exposure to each single factor minus 1 and multiplicative when joint effects exceeded the product of the effect of exposure to each single factor.
In females, an additive interaction was seen: simultaneous presence of HBV, HCV, and alcohol (OR 5.09; 95% CI, 1.06-24.56) exceeded the sum (4.14) of a single exposure (OR 0.72 for HBsAg positivity; OR 1.34 for antibody HCV positivity; and OR 2.08 for alcohol intake).
No interactions among risk factors were observed in males or when the genders were combined. Internal controls of patients extracted from the same population and exposed to similar selective factors were used to avoid spurious associations.
The additive effects of HBV, HCV, and risky alcohol use on the risk for cirrhosis may be explained by both virus and alcohol stimulation of hepatic-oxidative stress or by effects of alcohol on the immune system. The researchers concluded that, “females are at higher risk for liver cirrhosis than males and deserve a more careful surveillance.”
Stroffolini T, Sagnelli E, Andriulli A, et al; EPACRON study group. Sex difference in the interaction of alcohol intake, hepatitis B virus, and hepatitis C virus on the risk of cirrhosis. PLoS One. 2017;12:e0185710.