Background/AimsWe investigated factors associated with the disease progression and development of hepatocellular carcinoma (HCC) in chronic hepatitis B (CHB) patients during long-term oral nucleos(t)ide analog (NA) therapy.MethodsThis retrospective study included 524 naive CHB patients who received oral NA therapy for more than 48 weeks between January 2003 and December 2007. The primary outcome was 5-year cumulative probability of disease progression and HCC development. Disease progression was defined as cirrhosis development, cirrhotic complications, HCC or liver-related mortality.ResultsFor the 524 patients, the cumulative probabilities of disease progression and HCC development at 1, 2, 3, 4 and 5 years were 1.1%, 6.3%, 9.0%, 11.6%, and 16.2% and 0.2%, 1.8%, 3.6%, 5.8%, and 9.3%, respectively. In multivariate analysis, age >50 years (hazard ratio [HR], 1.05) and cirrhosis (HR, 2.95) were significant factors for disease progression. Similarly, age >50 years (HR, 1.05), family history of HCC (HR, 5.48), and cirrhosis (HR, 17.16) were significant factors for HCC development. Importantly, longer duration (>12 months) of maintained virological response (<20 IU/mL) reduced the risks of disease progression (HR, 0.19) and HCC development (HR, 0.09).ConclusionsLonger duration of maintained virological response significantly reduces the risk of disease progression or HCC development in CHB patients undergoing long-term oral NA therapy.