Table 4.
Interaction between MTHFR, MTR, MTRR or TS polymorphisms and drinking and smoking habit for head and neck squamous cell carcinoma risk
| Polymorphism | Drinking habit | Interaction P § | Smoking habit | Interaction P § | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Never drinker | Moderate drinker ‡ | Heavy drinker ‡ | Never smoker | Current smoker pack years 0–39 | Current smoker pack years ≥ 40 | |||||||||
| Cases/ controls | OR † (95% CI) | Cases/ controls | OR † (95% CI) | Cases/ controls | OR † (95% CI) | Cases/ controls | OR † (95% CI) | Cases/ controls | OR † (95% CI) | Cases/ controls | OR† (95% CI) | |||
| MTHFR (C677T) | ||||||||||||||
| CC + CT | 45/193 | 1.00 (ref.) | 85/286 | 1.48 (0.83–2.62) | 57/68 | 4.41 (2.06–9.44) | 48/211 | 1.00 (ref.) | 44/119 | 0.62 (0.27–1.43) | 52/82 | 1.57 (0.63–3.88) | ||
| TT | 11/42 | 1.94 (0.73–5.12) | 11/59 | 0.90 (0.34–2.38) | 5/15 | 1.61 (0.37–7.02) | 0.04 | 8/45 | 1.61 (0.51–5.01) | 8/15 | 0.98 (0.24–3.93) | 10/26 | 1.02 (0.26–3.99) | 0.30 |
| MTHFR (A1298C) | ||||||||||||||
| AA + AC | 55/223 | 1.00 (ref.) | 91/329 | 1.11 (0.64–1.92) | 60/80 | 3.15 (1.57–6.31) | 55/242 | 1.00 (ref.) | 52/127 | 0.57 (0.25–1.27) | 59/102 | 1.23 (0.50–3.03) | ||
| CC | 1/11 | 0.14 (0.01–1.46) | 4/14 | 1.09 (0.22–5.26) | 2/3 | 5.92 (0.17–206.63) | 0.13 | 1/12 | 0.07 (0.01–0.97) | 0/5 | NA ¶ | 3/6 | 2.75 (0.26–28.77) | 0.06 |
| MTR (A2756G) | ||||||||||||||
| AA + AG | 51/230 | 1.00 (ref.) | 91/337 | 1.20 (0.70–2.05) | 61/77 | 3.76 (1.84–7.69) | 54/251 | 1.00 (ref.) | 51/130 | 0.66 (0.29–1.48) | 59/106 | 1.35 (0.55–3.29) | ||
| GG | 5/5 | 4.49 (0.72–28.19) | 5/8 | 2.01 (0.47–8.60) | 1/6 | 0.62 (0.05–7.29) | 0.04 | 2/5 | 0.74 (0.08–6.64) | 1/4 | 0.26 (0.02–4.16) | 3/2 | 2.67 (0.07–106.29) | 0.75 |
| MTRR (A66G) | ||||||||||||||
| AA + AG | 51/213 | 1.00 (ref.) | 86/313 | 1.09 (0.63–1.87) | 52/78 | 2.61 (1.26–5.39) | 49/232 | 1.00 (ref.) | 45/123 | 0.68 (0.30–1.56) | 54/99 | 1.52 (0.61–3.81) | ||
| GG | 5/22 | 0.51 (0.14–1.91) | 10/32 | 1.76 (0.62–4.95) | 10/5 | 12.39 (2.51–61.25) | 0.03 | 7/24 | 1.68 (0.47–5.99) | 7/11 | 0.79 (0.15–4.13) | 8/9 | 1.41 (0.31–6.40) | 0.55 |
| TS VNTR | ||||||||||||||
| Non‐2R/Non‐2R | 37/172 | 1.00 (ref.) | 70/241 | 1.61 (0.86–3.00) | 44/55 | 4.23 (1.84–9.73) | 41/184 | 1.00 (ref.) | 37/93 | 0.77 (0.32–1.84) | 47/77 | 1.98 (0.75–5.23) | ||
| 2R/Non‐2R + 2R/2R | 19/63 | 1.92 (0.87–4.23) | 26/104 | 1.31 (0.61–2.81) | 18/28 | 4.02 (1.43–11.34) | 0.22 | 15/72 | 1.86 (0.77–4.53) | 15/41 | 0.62 (0.17–2.31) | 15/31 | 0.95 (0.26–3.47) | 0.08 |
Odds ratio (OR) was matched for age and sex and adjusted for drinking habit, smoking habit, non‐alcohol energy intake, carotene intake, vitamin C intake, vitamin E intake, folate intake, multivitamin use, dental brushing, and referral pattern to our hospital.
Moderate drinker means <46 g ethanol/drink and/or <5 days/week. Heavy drinker means ≥46 g ethanol/drink and ≥5 days/week.
Interactions were modeled as a product of drinking habit in score (0, never; 1, moderate drinker; and 2, heavy drinker), smoking habit in score (0, never; 1, 0–39 pack years; and 2, pack years ≥ 40) and genotype in score.
NA indicates that OR was not available because of insufficient data. CI, confidence interval.