Longitudinal Study on the Negative Conversion Rate of HBsAg Among Male Adults in Korea

Abstract

The negative conversion rate of HBsAg among adult males in Korea was estimated during a two-year follow-up study on a fixed cohort of 64 HBsAg positives tested by radioimmunoassay. The nagative conversion rate of HBsAg was 35.9% with its 95% Confidence Interval (CI) of 24.6-49.0°;;). The difference of rates estimated by age was not statistically significant, but the geometric mean titers of HBsAg decreased significantly by age. According to the ratio unit (RU) of HBsAg at enrollment, an inversed relationship between the ratio unit and the negative conversion rate was observed. Among in the less than 10 RU group, the negative conversion rate was 75% (95% CI: 50.6-90.4); among in the 10-49 RU group and in the larger than 50 RU group were 29.4% (95% CI: 11.4-55.9) and 11.1% (95% CI: 2.9-30.3), respectively.