Table 5.
Cumulative updated caffeine consumption and covariate-adjusted hazard ratio of colorectal, colon, and rectal cancer*
|
Quintiles of caffeine intake |
HR for additional 100 mg per caffeine per day (95% CI) |
||||||
|---|---|---|---|---|---|---|---|
| 1 | 2 | 3 | 4 | 5 | Ptrend† | ||
| Median intake, mg/day | |||||||
| Women | 72 | 181 | 290 | 396 | 602 | ||
| Men | 15 | 76 | 165 | 307 | 499 | ||
| Colorectal cancer | |||||||
| HR, women (95% CI)‡ | 1.00 (referent) |
1.05 (0.85 to 1.30) |
0.99 (0.80 to1.23) |
1.02 (0.82 to 1.27) |
1.02 (0.82 to1.27) |
0.95 | 1.00 (0.97 to 1.03) |
| HR, men (95% CI)‡ | 1.00 (referent) |
0.84 (0.64 to 1.09) |
0.88 (0.68 to1.15) |
0.96 (0.74 to1.25) |
0.88 (0.67 to1.16) |
0.90 | 1.00 (0.96 to1.04) |
| HR, pooled (95% CI)‡ | 1.00 (referent) |
0.96 (0.81 to1.14) |
0.95 (0.80 to1.12) |
1.00 (0.84 to1.18) |
0.96 (0.81 to 1.14) |
0.99 | 1.00 (0.98 to1.03) |
| No. of cases | 284 | 287 | 291 | 299 | 277 | 1 438 | |
| No. person-years of follow-up | 379 483 | 397 448 | 403 825 | 405 190 | 405 658 | 1 991 604 | |
| Colon cancer | |||||||
| HR, women (95% CI)‡ | 1.00 (referent) |
1.05 (0.83 to 1.32) |
0.97 (0.76 to 1.22) |
1.05 (0.83 to 1.33) |
0.97 (0.76 to 1.23) |
0.71 | 1.00 (0.96 to 1.03) |
| HR, men (95% CI)‡ | 1.00 (referent) |
0.87 (0.64 to 1.17) |
0.91 (0.68 to 1.23) |
0.99 (0.74 to 1.32) |
0.85 (0.63 to 1.16) |
0.67 | 1.00 (0.96 to 1.05) |
| HR, pooled (95% CI)‡ | 1.00 (referent) |
0.97 (0.81 to 1.17) |
0.94 (0.79 to 1.14) |
1.03 (0.85 to 1.23) |
0.92 (0.76 to 1.11) |
0.97 | 1.00 (0.97 to 1.02) |
| No. of cases | 233 | 237 | 238 | 252 | 217 | 1 177 | |
| No. person-years of follow-up | 379 562 | 397 519 | 403 912 | 405 243 | 405 719 | 1 991 955 | |
| Rectal cancer | |||||||
| HR, women(95% CI)‡ | 1.00 (referent) |
1.08 (0.65 to 1.81) |
1.13 (0.67 to 1.89) |
0.87 (0.50 to 1.51) |
1.28 (0.76 to 2.13) |
0.50 | 1.02 (0.95 to 1.10) |
| HR, men(95% CI)‡ | 1.00 (referent) |
0.69 (0.37 to 1.30) |
0.75 (0.41 to 1.39) |
0.86 (0.47 to 1.57) |
1.01 (0.55 to 1.83) |
0.54 | 1.01 (0.92 to 1.11) |
| HR, pooled (95% CI)‡ | 1.00 (referent) |
0.91 (0.61 to 1.35) |
0.95 (0.64 to 1.41) |
0.86 (0.57 to 1.30) |
1.15 (0.78 to 1.70) |
0.89 | 1.02 (0.96 to 1.08) |
| No. of cases | 51 | 50 | 53 | 47 | 60 | 261 | |
| No. person-years of follow-up | 379 808 | 397 849 | 404 221 | 405 551 | 406 014 | 1 993 443 | |
*
HR = hazard ratio; CI = confidence interval.
†
Wald test for trend; two-sided.
‡
Adjusted for age, family history of colorectal cancer, history of sigmoidoscopy, height, body mass index, pack-years of smoking, physical activity, aspirin use, vitamin supplement intake, alcohol consumption, red meat consumption, total caloric intake, and, among women in addition for menopausal status, postmenopausal hormone use.