Table 3.
Hazard Ratios (HRs) and 95% confidence intervals (CIs) of hepatocellular carcinoma (HCC) according to hepatitis B and C virus infection status
| Infection status | No. of subjects | Person-years | No. of HCC | HRa(95% CI) |
|---|---|---|---|---|
| HBsAg(−) / anti-HCV(−) |
5744 |
53,504 |
16 |
1.0 (reference) |
| HBsAg(+) / anti-HCV(−) |
335 |
2,981 |
15 |
17.1 (8.4-34.8) |
| HBsAg(−) / anti-HCV(+) |
360 |
3,731 |
12 |
10.4 (4.9-22.1) |
| HBsAg(+) / anti-HCV(+) |
14 |
133 |
3 |
115.0 (32.5-407.3) |
| SI and 95% CI: 4.5 (1.3-15.5)b |
HBsAg, hepatitis B surface antigen; anti-HCV, antibodies against hepatitis C virus. aHR: age- and sex-adjusted. bSI: synergy index=(RR11-1)/(RR01+RR10-2), in which RR11=relative risk of the joint effect of two risk factors; RR01 and RR10=relative risk of each risk factor in the absence of the other. Two hundred and forty-one subjects including 4 HCC cases had no information on HBsAg or anti-HCV, and were excluded from the analysis.