Table 3.
Stratified analyses about IL18 −137 G/C polymorphism
| Category | n | Case/controls | C allele vs G allele (allele model) OR (95% CI), P, Ph | CC vs GG (homozygous model) OR (95% CI), P, Ph | GC vs GG (heterozygous model) OR (95% CI), P, Ph | GC+CC vs GG (dominant model) OR (95% CI), P, Ph | CC vs GG+GC (recessive model) OR (95% CI), P, Ph |
|---|---|---|---|---|---|---|---|
| Total | 12 | 1997/3275 | 1.31 (1.09–1.57), 0.004, 0.002* | 1.69 (1.20–2.38), 0.003, 0.175* | 1.27 (1.01–1.59), 0.039, 0.004* | 1.32 (1.06–1.65), 0.012, 0.002* | 1.53 (1.13–2.06), 0.006, 0.321* |
| Cancer type | |||||||
| Thyroid | 1.03 (0.75–1.41), 0.864, 0.657 | 2.41 (0.58–10.09), 0.227, 0.114 | 077 (0.52–1.15), 0.198, 0.603 | 0.89 (0.61–1.29), 0.522, 0.968 | 2.60 (0.61–11.17), 0.199, 0.104 | ||
| Esophageal | 1.33 (0.70–2.50), 0.382, 0.001 | 1.56 (0.49–4.96), 0.451, 0.028 | 1.36 (0.72–2.59), 0.346, 0.011 | 1.39 (0.68–2.85), 0.363, 0.003 | 1.39 (0.55–3.52), 0.493, 0.072 | ||
| Nasopharyngeal | 1.48 (1.20–1.83), 0.000, 0.222* | 2.01 (1.30–3.10), 0.002, 0.598* | 1.53 (1.22–1.93), 0.000, 0.365* | 1.60 (1.26–2.02), 0.000, 0.306* | 1.72 (1.12–2.63), 0.012, 0.664* | ||
| Others | 1.23 (0.70–2.17), 0.478, 0.015 | 1.19 (0.60–2.35), 0.626, 0.397 | 1.23 (0.61–2.46), 0.566, 0.017 | 1.24 (0.63–2.43), 0.538, 0.015 | 1.19 (0.61–2.33), 0.614, 0.531 | ||
| Ethnicity | |||||||
| Asian | 1.40 (1.13–1.74), 0.002, 0.012* | 2.03 (1.38–2.99), 0.000, 0.332* | 1.33 (0.98–1.79), 0.066, 0.003 | 1.41 (1.06–1.86), 0.017, 0.004* | 1.83 (1.28–2.61), 0.001, 0.469* | ||
| European | 1.08 (0.80–1.44), 0.623, 0.211 | 1.25 (0.52–3.04), 0.620, 0.166 | 1.05 (0.79–1.38), 0.752, 0.509 | 1.05 (0.81–1.37), 0.711, 0.331 | 1.19 (0.54–2.58), 0.669, 0.203 | ||
| African | 1.15 (0.82–1.61), 0.413, — | 1.28 (0.57–2.86), 0.552, — | 1.19 (0.75–1.87), 0.458, — | 1.20 (0.78–1.86), 0.406, — | 1.18 (0.54–2.56), 0.680, — | ||
| Genotyping methods | |||||||
| PCR-RFLP | 1.38 (1.04–1.83), 0.024, 0.050* | 1.84 (1.19–2.83), 0.006, 0.503* | 1.39 (0.99–1.95), 0.056, 0.078 | 1.44 (1.03–2.03), 0.035, 0.053* | 1.61 (1.06–2.46), 0.027, 0.663* | ||
| AS-PCR | 1.32 (0.85–2.03), 0.214, 0.016 | 1.81 (0.86–3.81), 0.116, 0.169 | 1.28 (0.77–2.12), 0.345, 0.034 | 1.34 (0.79–2.27), 0.281, 0.018 | 1.64 (0.94–2.87), 0.080, 0.343 | ||
| Others | 1.21 (0.85–1.72), 0.296, 0.024 | 1.73 (0.65–4.58), 0.272, 0.063 | 1.10 (0.67–1.79), 0.713, 0.008 | 1.17 (0.76–1.79), 0.482, 0.017 | 1.73 (0.63–4.74), 0.283, 0.051 | ||
| Source of control | |||||||
| Population-based | 1.27 (1.02–1.59), 0.035, 0.016* | 1.47 (1.00–2.16), 0.050, 0.320 | 1.27 (1.00–1.61), 0.048, 0.075 | 1.30 (1.01–1.67), 0.038, 0.035* | 1.35 (0.96–1.89), 0.085, 0.490 | ||
| Hospital-based | 1.36 (0.96–1.92), 0.081, 0.014 | 2.14 (1.11–4.12), 0.024, 0.137* | 1.24 (0.74–2.08), 0.408, 0.002 | 1.34 (0.84–2.15), 0.215, 0.004 | 1.92 (1.04–3.52), 0.036, 0.181* |
Note:
*
95%CI did not include 0.
Abbreviations: OR, odds ratio; CI, confidence interval; PCR-RFLP, polymerase chain reaction-restriction fragment length polymorphism; AS-PCR, alleles specific polymerase chain reaction; Ph, p-value of the heterogenety.