Table 4. Adjusted odds ratio (AOR) and 95% confidence intervals (CIs) of oral cancer associated with genotypic frequencies of IL-18 -607A/C and IL-18 -137G/C among individuals non-exposure to related environmental risk factors.
| Variable | Controls | Patients | AOR (95% CI) | p value |
|---|---|---|---|---|
| Among non-areca consumption (n=600) | ||||
| IL-18 -607 | Control (n=466) (%) | Case (n=134) (%) | AOR (95% CI) | p value |
| CC | 114 (24.5%) | 27 (20.2%) | 1.00 | |
| AC | 226 (48.5%) | 72 (53.7%) | 1.12 (0.66-1.90) | p=0.65 |
| AA | 126 (27.0%) | 35 (26.1%) | 1.03 (0.57-1.86) | p=0.91 |
| IL-18 -137 | ||||
| GG | 397 (85.2%) | 107 (79.9%) | 1.00 | |
| GC | 66 (14.2%) | 26 (19.4%) | 1.41 (0.82-2.41) | p=0.21 |
| CC | 3 (0.6%) | 1 (0.7%) | 1.32 (0.13-13.08) | p=0.80 |
| IL-18 genes combination | ||||
| Group 1 | 111 (23.8%) | 27 (20.2%) | 1.00 | |
| Group 2 | 289 (62.0%) | 80 (59.6%) | 0.97 (0.58-1.62) | p=0.91 |
| Group 3 | 66 (14.2%) | 27 (20.2%) | 1.43 (0.74-2.74) | p=0.27 |
| Among non-alcohol consumption (n=576) | ||||
| IL-18 -607 | Control (n=345) (%) | Case (n=231) (%) | AOR (95% CI) | p value |
| CC | 75 (21.7%) | 59 (25.5%) | 1.00 | |
| AC | 172 (49.9%) | 103 (44.6%) | 0.59 (0.34-1.01) | p=0.06 |
| AA | 98 (28.4%0 | 69 (29.9%) | 0.63 (0.34-1.14) | p=0.12 |
| IL-18 -137 | ||||
| GG | 277 (80.3%) | 170 (73.6%) | 1.00 | |
| GC | 64 (18.5%) | 59 (25.5%) | 1.19 (0.71-2.01) | p=0.50 |
| CC | 4 (1.2%) | 2 (0.9%) | 0.26 (0.03-1.85) | p=0.17 |
| IL-18 genes combination | ||||
| Group 1 | 71 (20.6%) | 59 (25.5%) | 1.00 | |
| Group 2 | 210 (60.9%) | 111 (48.1%) | 0.51 (0.30-0.87) | p=0.01 |
| Group 3 | 64 (18.5%) | 61 (26.4%) | 0.72 (0.38-1.37) | p=0.32 |
| Among non-tobacco consumption (n=424) | ||||
| IL-18 -607 | Control (n=339) (%) | Case (n=85) (%) | AOR (95% CI) | P value |
| CC | 76 (22.4%) | 17 (20.0%) | 1.00 | |
| AC | 169 (49.9%) | 43 (50.6%) | 0.89 (0.45-1.76) | p=0.74 |
| AA | 94 (27.7%) | 25 (29.4%) | 0.93 (0.43-1.99) | p=0.85 |
| IL-18 -137 | ||||
| GG | 291 (85.8%) | 65 (76.5%) | 1.00 | |
| GC | 45 (13.3%) | 20 (23.5%) | 1.73 (0.86-3.45) | p=0.12 |
| CC | 3 (0.9%) | 0 (0%) | ─ | p=0.98 |
| IL-18 genes combination | ||||
| Group 1 | 74 (21.8%) | 171 (20.0%) | 1.00 | |
| Group 2 | 219 (64.6%) | 48 (56.5%) | 0.78 (0.40-1.52) | p=0.47 |
| Group 3 | 46 (13.6%) | 20 (23.5%) | 1.36 (0.59-3.16) | p=0.46 |
The odds ratios (ORs) with their 95% confidence intervals (CIs) were estimated by logistic regression models.
The adjusted odds ratios (AORs) with their 95% confidence intervals (CIs) were estimated by multiple logistic regression models, after controlling for gender, age, alcohol, tobacco, and areca consumption.
Group 1: individuals with CC of IL-18 -607 and GG of IL-18 -137; Group 2: individuals with at least one of the following, including A/C or A/A of IL-18 -607, or G/C or C/C of IL-18 -137; Group 3: individuals with A/C or A/A of IL-18 -607, and G/C or C/C of IL-18 -137.