Table 2. Subgroup analyses of BMI and liver cancer incidence.
| Overweight | Heterogeneity | interaction | Obesity | Heterogeneity | interaction | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| No. of studies | RR (95 CI%) | P | I2 (%) | P | No. of studies | RR (95 CI%) | P | I2 | P | |
| Over all Incidence | 13 | 1.16 (1.08, 1.25) | 0.016 | 45.0 | 15 | 1.83 (1.60, 2.09) | 0 | 59 | ||
| Sex | ||||||||||
| Men | 13 | 1.18 (1.01, 1.30) | 0.004 | 58.7 | 14 | 2.04 (1.70, 2.44) | 0 | 65.8 | ||
| Women | 7 | 1.11 (1.00, 1.24) | 0.500 | 0 | 0.47 | 9 | 1.56 (1.37, 1.78) | 0.414 | 2.5 | 0.02 |
| Study location | ||||||||||
| Non-Asia | 7 | 1.21 (1.11, 1.33) | 0.365 | 8.3 | 10 | 1.95 (1.64, 2.31) | 0 | 64.6 | ||
| Asia | 6 | 1.10 (1.00, 1.22) | 0.050 | 48, 5 | 0.16 | 5 | 1.56 (1.34, 1.81) | 0.656 | 0 | 0.05 |
| Non-Asia | ||||||||||
| Non-Asia (M) | 7 | 1.28 (1.16, 1.40) | 0.559 | 0 | 10 | 2.31 (1.85, 2.91) | 0.001 | 67.9 | ||
| Non-Asia (W) | 4 | 1.06 (0.90, 1.23) | 0.600 | 0 | 0.04 | 7 | 1.56 (1.31, 1.86) | 0.312 | 15.5 | 0.01 |
| Asia | ||||||||||
| Asia (M) | 6 | 1.07 (0.96, 1.20) | 0.049 | 55.1 | 4 | 1.57 (1.32, 1.87) | 0.534 | 0 | ||
| Asia (W) | 3 | 1.23 (0.95, 1.59) | 0.275 | 22.5 | 0.33 | 2 | 1.53 (1.14, 2.06) | 0.301 | 6.4 | 0.88 |
| Study location | ||||||||||
| Sweden | 2 | 1.36 (1.08, 1.70) | 0.453 | 0 | 3 | 3.07 (2.19, 4.32) | 0.148 | 43.8 | ||
| Non-Sweden | 11 | 1.16 (1.05, 1.28) | 0.006 | 59.6 | 0.21 | 12 | 1.60 (1.52, 1.85) | 1 | 0 | 0 |
| Study design | ||||||||||
| Cohort | 10 | 1.16 (1.06, 1.26) | 0.007 | 53.8 | 11 | 1.85 (1.60, 2.14) | 0.001 | 61.7 | ||
| Case-control | 3 | 1.20 (1.00, 1.44) | 0.526 | 0 | 0.74 | 4 | 1.72 (1.19, 2.49) | 0.025 | 58.4 | 0.72 |
| Disease type | ||||||||||
| Liver cancer | 10 | 1.13 (1.05, 1.21) | 0.054 | 39, 3 | 11 | 1.81 (1.56, 2.09) | < 0.001 | 62.4 | ||
| HCC | 3 | 1.38 (1.12, 1.70) | 0.325 | 13.5 | 0.08 | 4 | 1.93 (1.33, 2.80) | 0.146 | 41.3 | 0.75 |
| Duration of follow-up (cohort studies only ) | ||||||||||
| ≥ 10 | 7 | 1.20 (1.09, 1.33) | 0.001 | 67.4 | 6 | 1.84 (1.54, 2.19) | 0 | 66.9 | ||
| < 10 | 3 | 0.98 (0.75, 1.28) | 0.621 | 0 | 0.16 | 4 | 1.88 (1.42, 2.50) | 0.107 | 44.8 | 0.90 |
| Study size | ||||||||||
| ≥ 30000 | 7 | 1.11 (1.04, 1.20) | 0.059 | 45.1 | 8 | 1.73 (1.47, 2.03) | 0.002 | 64.9 | ||
| < 30000 | 6 | 1.32 (1.11, 1.57) | 0.203 | 26.1 | 0.07 | 7 | 1.99 (1.57, 2.51) | 0.015 | 53.2 | 0.34 |
| Adjustment factors | ||||||||||
| Smoking | ||||||||||
| yes | 12 | 1.15 (1.07, 1.24) | 0.022 | 43.7 | 11 | 1.72 (1.47, 2.01) | <0.001 | 62.6 | ||
| no | 1 | 1.57 (1.01, 2.45) | 0.17 | 4 | 2.20 (1.73, 2.81) | 0.2 | 31.5 | 0.09 | ||
| Alcohol | ||||||||||
| yes | 9 | 1.18 (1.06, 1.31) | 0.013 | 50.5 | 9 | 1.67 (1.45, 3.51) | 0.072 | 38.3 | ||
| no | 4 | 1.14 (1.01, 1.29) | 0.186 | 35.3 | 0.68 | 6 | 2.14 (1.64, 2.78) | 0 | 71.5 | 0.35 |