Table 3.
Association of smoking and alcohol consumption with CRC risk by molecular pathological pathways.
| Regular smoking | Alcohol: g/ethanol/daya | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Never | Ever | Former | Current | ≤24.6 | >24.6 | |||||
| N (%) | N (%) | OR (95% CI)b | N (%) | OR (95% CI)b | N (%) | OR (95% CI)b | N (%) | N (%) | OR (95% CI)b | |
| Controls | 1235 (51.1) | 1183 (49.4) | 1 | 916 (37.9) | 1 | 267 (11.0) | 1 | 1953 (80.8) | 465 (19.2) | 1 |
| Traditional pathway | 414 (44.5) | 517 (55.5) | 1.30 (1.09–1.54) | 368 (39.5) | 1.23 (1.02–1.49) | 149 (16.0) | 1.50 (1.16–1.94) | 680 (73.0) | 251 (27.0) | 1.57 (1.16–2.11) |
| Sessile serrated pathway | 65 (53.7) | 56 (46.3) | 1.55 (1.01–2.36) | 41 (33.9) | 1.34 (0.85–2.13) | 15 (12.4) | 2.39 (1.27–4.52) | 101 (83.5) | 20 (16.5) | 1.84 (0.75–4.52) |
| p-het traditional vs. sessile serrated | 0.340 | 0.604 | 0.163 | 0.850 | ||||||
| Alternate pathway | 254 (49.4) | 260 (50.6) | 1.11 (0.9–1.39) | 197 (38.3) | 1.13 (0.89–1.43) | 63 (12.3) | 1.08 (0.77–1.52) | 397 (77.2) | 117 (22.8) | 1.15 (0.80–1.66) |
| p-het traditional vs. alternate | 0.171 | 0.425 | 0.062 | 0.243 | ||||||
aLogistic regression model adjusted for: Sex, age, BMI, education level, history of colorectal cancer in first-degree relative, previous endoscopy, diabetes, ever NSAIDs regular use and average lifetime alcohol consumption/ever regular smoking. Ever/former/current smoking compared to never smoking. High alcohol intake compared to low/none. Traditional pathway: MSS, CIMP-low/negative, BRAF-wt and KRAS-wt; sessile serrated pathway: CIMP-high, BRAF-mut; alternate pathway: MSS, CIMP-low/negative, KRAS-mut.
bHigh alcohol consumption was defined as the third quartile of the average daily lifetime gram ethanol consumption among alcohol drinkers (>24.6 g) and was compared in analyses to low/never consumption (≤24.6 g).