Table 3. Interaction of HBsAg and anti-HCV positivity, alcohol intake, cigarette smoking, and family income on HCC risk.
| Factor 1 | Factor 2 | Case, N=207 (%) | Control, N=828 (%) | OR (95% CI) a |
|---|---|---|---|---|
| HBsAg | Anti-HCV | |||
| Negative | Negative | 23 (11.1) | 777 (93.8) | Reference |
| Negative | Positive | 23 (11.1) | 4 (0.5) | 255.71 (64.71–∞) |
| Positive | Negative | 160 (77.3) | 46 (5.6) | 158.66 (83.00–303.30) |
| Positive | Positive | 1 (0.5) | 1 (0.1) | 15.90 (0.75–335.51) |
| SI and 95% CI: 0.04 (0.00–1.02)b | ||||
| HBsAg | Lifetime alcohol intake (Absolute alcohol concentration, g per day) | |||
| Negative | <24 | 25 (12.1) | 596 (72.0) | Reference |
| Negative | ⩾24 | 21 (10.1) | 185 (22.3) | 2.96 (1.29–6.79) |
| Positive | <24 | 99 (47.8) | 36 (4.4) | 153.99 (72.51–327.00) |
| Positive | ⩾24 | 62 (30.0) | 11 (1.3) | 367.11 (135.48–994.74) |
| SI and 95% CI: 2.36 (0.99–5.65)b | ||||
| HBsAg | Cigarette smoking | |||
| Negative | Never | 13 (6.3) | 382 (46.1) | Reference |
| Negative | Ever | 33 (15.9) | 399 (48.2) | 3.53 (1.31–9.52) |
| Positive | Never | 61 (29.5) | 21 (2.5) | 363.79 (120.65–∞) |
| Positive | Ever | 100 (48.3) | 26 (3.1) | 317.62 (109.22–923.60) |
| SI and 95% CI: 0.87 (0.39–1.92)b | ||||
| HBsAg | Family income (US$ per month) | |||
| Negative | ⩾4000 | 4 (1.9) | 436 (52.7) | Reference |
| Negative | <4000 | 42 (20.3) | 345 (41.7) | 17.07 (4.27–68.25) |
| Positive | ⩾4000 | 37 (17.9) | 23 (2.8) | 531.97 (121.16–∞) |
| Positive | <4000 | 124 (59.9) | 24 (2.9) | >999.99 (397.07–∞) |
| SI and 95% CI: 3.12 (1.51–6.47)b |
Abbreviations: HbsAg=serologic marker of hepatitis B virus surface antigen; anti-HCV antibody=serologic marker of hepatitis C virus antibody; OR=odds ratio; 95% CI=95% confidence interval.
a
Multiple logistic regression analysis adjusted for gender, age, marital status, family income, lifetime alcohol intake, cigarette smoking, BMI, and positivity of HBsAg and anti-HCV as appropriate.
b
SI: synergic index=(OR11−1)/(OR01+OR10−2), in which OR11=odds ratio of the joint effect of two risk factors; OR01 and OR10=odds ratio of each risk factor in the absence of the other.