Background: Identifying risk factors for the development of complications of chronic hepatitis B (CHB) is important for setting up treatment criteria.

Aim: To determine risk factors for the development of complications in Asian CHB patients.

Patients and methods: A total of 3233 Chinese CHB patients (mean follow up 46.8 months) were monitored for liver biochemistry, viral serology, hepatitis B virus (HBV) DNA levels, acute exacerbation, hepatitis B e antigen (HBeAg) seroconversion, and development of cirrhotic complications and hepatocellular carcinoma.

Results: Median age for HBeAg seroconversion and development of complications was 35 years and 57.2 years, respectively. Patients with alanine aminotransferase (ALT) levels of 0.5-1 times the upper limit of normal (ULN) and 1-2x ULN had an increased risk for the development of complications compared with patients with ALT levels <0.5x ULN (p<0.0001 for both). HBeAg/antibody to hepatitis B e antigen status, and number of episodes, duration, and peak ALT levels of acute exacerbations were not associated with an increased risk of complications. In patients with complications, 43.6% had HBV DNA levels less than 1.42x10(5) copies/ml. Male sex, stigmata of chronic liver disease, old age, low albumin, and high alpha fetoprotein levels on presentation were independently associated with increased cumulative risk of complications. Male sex, presence of hepatitis symptoms, old age, low albumin level, and presence of complications on presentation were independently associated with shorter survival.

Conclusion: Prolonged low level viraemia causing insidious and continual liver damage, as reflected by ALT levels of 0.5-2x ULN, is the most likely pathway for the development of complications in Asian CHB patients.