Aflatoxin B 1 exposure increases the risk of cirrhosis and hepatocellular carcinoma in chronic hepatitis B virus carriers

The relation between aflatoxin B 1 (AFB 1 ) and cirrhosis in chronic carriers of hepatitis B virus (HBV) remains inconclusive. This case‐control study nested in a large community‐based cohort aimed to assess the effect of AFB 1 exposure on cirrhosis and HCC in chronic HBV carriers. Serum AFB 1 ‐albumin adduct levels at study entry were measured in 232 cirrhosis cases, 262 HCC cases and 577 controls. Multivariate‐adjusted odds ratios (aORs) and 95% confidence intervals (95% CIs) were estimated using logistic regression. Among all chronic HBV carriers, the time intervals between study entry and diagnosis of HCC, cirrhosis, cirrhotic HCC, and non‐cirrhotic HCC were all significantly ( p  < 0.0001) shorter in participants with high serum levels of AFB 1 ‐albumin adducts than those with low/undetectable levels. There were significant dose‐response relations with serum AFB 1 ‐albumin adduct level at study entry for cirrhosis ( p ‐trend = 0.0001) and cirrhotic HCC ( p ‐trend < 0.0001) newly diagnosed within 9 years after entry as well as non‐cirrhotic HCC ( p ‐trend = 0.021) newly diagnosed within 4 years after entry. The aORs (95% CIs) for high versus undetectable serum AFB 1 ‐albumin adduct levels were 2.45 (1.51–3.98) for cirrhosis ( p  = 0.0003), 5.47 (2.20–13.63) for cirrhotic HCC ( p  = 0.0003), and 5.39 (1.11–26.18) for non‐cirrhotic ( p  = 0.0368) HCC, respectively. There remained a significant dose‐response relation between serum AFB 1 ‐albumin adduct level and HCC risk ( p ‐trend = 0.0291) in cirrhosis patients, showing an aOR (95% CI) of 3.04 (1.11–8.30) for high versus undetectable serum levels ( p  = 0.0299). It is concluded that AFB 1 exposure may increase the risk of cirrhosis and HCC in a dose‐response manner among chronic HBV carriers.