TABLE 5.
Joint associations of self-reported unrestrained eating and physical activity with digestive system cancer risk1
| No and active2 | No and Inactive2 | Yes and Active2 | Yes and Inactive2 | P-interaction3 | |
|---|---|---|---|---|---|
| Joint associations according to eating anything at any time and physical activity | |||||
| All digestive system cancers | |||||
| Cases | 529 | 978 | 131 | 426 | |
| Multivariable4 | 1 [Reference] | 1.12 (1.00, 1.24) | 1.09 (0.90, 1.32) | 1.41 (1.23, 1.61) | 0.20 |
| Gastrointestinal tract cancers | |||||
| Cases | 361 | 657 | 98 | 311 | |
| Multivariable4 | 1 | 1.11 (0.97, 1.27) | 1.20 (0.95, 1.50) | 1.54 (1.31, 1.80) | 0.27 |
| Colorectal cancer | |||||
| Cases | 283 | 516 | 73 | 224 | |
| Multivariable4 | 1 | 1.11 (0.96, 1.29) | 1.17 (0.90, 1.52) | 1.44 (1.20, 1.74) | 0.51 |
| Joint associations according to no concern with figure change and physical activity | |||||
| All digestive system cancers | |||||
| Cases | 511 | 762 | 195 | 613 | |
| Multivariable4 | 1 | 1.06 (0.95, 1.19) | 0.97 (0.82, 1.15) | 1.20 (1.06, 1.36) | 0.14 |
| Gastrointestinal tract cancers | |||||
| Cases | 362 | 535 | 134 | 424 | |
| Multivariable4 | 1 | 1.06 (0.93, 1.22) | 0.95 (0.78, 1.16) | 1.19 (1.03, 1.39) | 0.17 |
| Colorectal cancer | |||||
| Cases | 280 | 416 | 107 | 329 | |
| Multivariable4 | 1 | 1.08 (0.92, 1.26) | 1.00 (0.80, 1.25) | 1.23 (1.04, 1.46) | 0.32 |
| Joint associations according to eating anything at any time + no concern with figure change and physical activity | |||||
| All digestive system cancers | |||||
| Cases | 391 | 584 | 61 | 232 | |
| Multivariable4 | 1 | 1.09 (0.95, 1.24) | 1.09 (0.83, 1.44) | 1.44 (1.20, 1.71) | 0.23 |
| Gastrointestinal tract cancers | |||||
| Cases | 277 | 398 | 50 | 172 | |
| Multivariable4 | 1 | 1.05 (0.90, 1.23) | 1.30 (0.96, 1.77) | 1.57 (1.28, 1.93) | 0.44 |
| Colorectal cancer | |||||
| Cases | 218 | 308 | 41 | 125 | |
| Multivariable4 | 1 | 1.04 (0.87, 1.24) | 1.43 (1.01, 2.01) | 1.51 (1.19, 1.91) | 0.95 |
Data are expressed as HRs and 95% CIs or numbers of cases unless otherwise indicated. MET, metabolic equivalent task; NHS, Nurses’ Health Study.
Self-reported behavior of unrestrained eating was dichotomized into a “no” category compared with a “yes” category, physical activity was dichotomized into an “active” category (≥18 MET-h/wk) compared with an “inactive” category (<18 MET-h/wk), resulting in 4 categories (no and active, no and inactive, yes and active, and yes and inactive, i.e., not having this behavior and being physically active, not having this behavior and being physically inactive, having this behavior and being physically active, and having this behavior and being physically inactive).
P value for interaction was calculated using the multiplication of status of having this behavior (0 for “no” and 1 for “yes”) and physical activity (0 for “active” and 1 for “inactive”).
HRs and 95% CIs were generated by Cox proportional hazards analyses adjusted for the same sets of covariates as denoted in Table 2.