Table 5.
Summary HRs and 95% CIs derived from meta-analyses with CHANCES cohort-specific estimates for the association of smoking status and time since smoking cessation with overall and CRC-specific survival in all CRC patients according to time between smoking exposure assessment and CRC diagnosis
| Recent assessment of smoking exposurea |
Distant assessment of smoking exposurea |
|||||
|---|---|---|---|---|---|---|
| At risk | Events | HR (95% CI)b | At risk | Events | HR (95% CI)b | |
| Overall survival | ||||||
| Smoking status | ||||||
| Never | 2068 | 895 | 1.00 (Reference) | 2202 | 780 | 1.00 (Reference) |
| Former | 3342 | 1529 | 1.15 (1.05–1.26) | 2768 | 1002 | 1.13 (1.01–1.25) |
| Current | 900 | 547 | 1.41 (1.12–1.77) | 1131 | 474 | 1.30 (1.08–1.57) |
| Time since smoking cessationc | ||||||
| Current | 881 | 533 | 1.00 (Reference) | 1035 | 414 | 1.00 (Reference) |
| <10 years | 812 | 404 | 0.79 (0.65–0.97) | 521 | 185 | 0.80 (0.65–0.99) |
| ≥10 years | 2461 | 1080 | 0.69 (0.54–0.90) | 2045 | 690 | 0.88 (0.67–1.15) |
| CRC-specific survival | ||||||
| Smoking status | ||||||
| Never | 2068 | 571 | 1.00 (Reference) | 2202 | 550 | 1.00 (Reference) |
| Former | 3342 | 838 | 1.01 (0.90–1.14) | 2768 | 615 | 1.04 (0.91–1.18) |
| Current | 900 | 320 | 1.37 (1.18–1.59) | 1131 | 299 | 1.22 (1.03–1.43) |
| Time since smoking cessationc | ||||||
| Current | 881 | 311 | 1.00 (Reference) | 1035 | 259 | 1.00 (Reference) |
| <10 years | 812 | 202 | 0.70 (0.41–1.21) | 521 | 103 | 0.76 (0.57–1.00) |
| ≥10 years | 2461 | 617 | 0.74 (0.64–0.86) | 2045 | 432 | 0.89 (0.69–1.15) |
Smoking exposure assessment was considered recent or distant if ascertained <6 years or ≥ 6 years before CRC diagnosis, respectively.
HRs and 95% CIs were adjusted for sex, age, BMI, education, alcohol intake, tumor site, diabetes and vigorous physical activity; adjustment for vigorous physical activity was not possible in MORGAM FI and SE; adjustment for diabetes was not possible in MORGAM FI.
Since time since smoking cessation information was not available for MORGAM FI and Rotterdam Study (RS), the number of current smokers in the reference category also excludes patients from these two studies; in analyses on smoking status these two studies were not excluded.