Interferon is the only treatment option in chronic delta hepatitis (CDH). A CDH database (333 patients, 161 with interferon treatment history) was analyzed for effects of treatment duration on virologic response and clinical outcomes. Ninety-nine CDH patients who received at least 6 months of interferon were selected. Maintained virologic response (MVR) was defined as hepatitis D virus RNA negative for 2 years after treatment discontinuation. Cumulative median interferon treatment duration was 24 months (range 6–126 months), with a median of 2 courses (range 1–8). Post-treatment median follow-up was 55 months (24–225 months). Thirty-five patients achieved MVR. Cumulative probability of MVR increased with treatment duration and reached 50% at 5 years. Patients with MVR were less likely to die from liver disease or develop complications compared to patients without MVR (P = .032, P = .006, respectively). Cirrhosis at baseline and no response to therapy (odds ratio 16.1 and 5.23, respectively) predicted an adverse endpoint. Hepatitis B surface antigen clearance occurred in 37% of patients with MVR. Viral response to interferon increases with treatment duration and favorably affects the natural course of disease. Interferon treatment duration has to be individualized with careful post-treatment assessment.

To provide a clear picture of the current hepatitis B situation, the authors performed a systematic review to estimate the age- and region-specific prevalence of chronic hepatitis B (CHB) in Turkey.