Effects of alcohol and folate intake according to MTHFR 677 C>T genotype for the colorectal cancer and adenoma study
| Colorectal cancer | Colorectal adenoma | |||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| CC/CT | TT | CC/CT | TT | |||||||||||||||||||
| Controls, n (%) | Cases, n (%) | OR (95% CI)* | Controls, n (%) | Cases, n (%) | OR (95% CI)* | Controls, n (%) | Cases, n (%) | OR (95% CI)* | Controls, n (%) | Cases, n (%) | OR (95% CI)* | |||||||||||
| Alcohol intake† | 540 | 421 | 48 | 53 | 269 | 267 | 27 | 41 | ||||||||||||||
| 0 | 215 (39.8) | 115 (27.3) | 1.00 | 20 (41.7) | 23 (43.4) | 1.00 | 65 (24.2) | 54 (20.2) | 1.00 | 10 (37.0) | 8 (19.5) | 1.00 | ||||||||||
| 1-13 | 215 (39.8) | 157 (37.3) | 1.37 (1.00-1.88) | 21 (43.8) | 16 (30.2) | 0.53 (0.20-1.44) | 105 (39.0) | 104 (39.0) | 1.14 (0.72-1.80) | 10 (37.0) | 14 (34.2) | 1.88 (0.47-7.47) | ||||||||||
| ≥14 | 110 (20.4) | 149 (35.4) | 2.55 (1.73-3.76) | 7 (14.6) | 14 (26.4) | 1.63 (0.41-6.55) | 99 (36.8) | 109 (40.8) | 0.99 (0.59-1.66) | 7 (25.9) | 19 (46.3) | 3.83 (0.77-19.2) | ||||||||||
| Overall trend | 1.58 (1.30-1.92) | 1.07 (0.56-2.07) | 0.99 (0.76-1.28) | 1.96 (0.88-4.38) | ||||||||||||||||||
| Likelihood ratio, χ2 (df)‡ | 1.15 (1), P = 0.28 | 1.45 (1), P = 0.23 | ||||||||||||||||||||
| Folate intake§ | 536 | 407 | 48 | 51 | 269 | 267 | 27 | 41 | ||||||||||||||
| ≤276.07 | 140 (26.1) | 101 (24.8) | 1.00 | 9 (18.9) | 15 (29.4) | 1.00 | 71 (26.4) | 96 (36.0) | 1.00 | 4 (14.8) | 12 (29.3) | 1.00 | ||||||||||
| 276.08-397.86 | 261 (48.7) | 196 (48.2) | 1.04 (0.76-1.43) | 24 (50.0) | 25 (49.0) | 0.83 (0.29-2.39) | 122 (45.4) | 117 (43.8) | 0.71 (0.48-1.08) | 14 (51.9) | 24 (58.5) | 0.54 (0.14-2.04) | ||||||||||
| ≥397.87 | 135 (25.2) | 110 (27.0) | 1.15 (0.80-1.65) | 15 (31.3) | 11 (21.6) | 0.65 (0.19-2.18) | 76 (28.3) | 54 (20.2) | 0.53 (0.33-0.85) | 9 (33.3) | 5 (12.2) | 0.19 (0.04-0.91) | ||||||||||
| Overall trend | 1.05 (0.93-1.18) | 0.87 (0.59-1.28) | 0.81 (0.70-0.95) | 0.57 (0.35-0.95) | ||||||||||||||||||
| Likelihood ratio, χ2 (df)‡ | 2.31 (1), P = 0.13 | 1.71 (1), P = 0.19 | ||||||||||||||||||||
NOTE: Adjusted odds ratios and 95% CI.
Abbreviation: df, degrees of freedom.
↵* Adjusted by sex and age.
↵† Alcohol consumption (U/wk) at 40 y of age, with limits based on quartiles derived from population controls.
↵‡ Test of interaction between alcohol consumption and MTHFR 677 using the likelihood ratio test based on the trend model.
↵§ Folate intake derived from nutrient analysis, including folate supplements but excluding folate from alcohol.