Individual associations of the polygenic risk score and the healthy lifestyle score with colorectal cancer risk
| Variables | CRC cases, n (%) | Controls, n (%) | OR (95%CI)1 | OR (95% CI)2 | GRE (95% CI) |
|---|---|---|---|---|---|
| PRS3 | |||||
| Low | 1,026 (21.3) | 1,317 (33.4) | Ref. | Ref. | |
| Moderate | 1,544 (32.1) | 1,313 (33.3) | 1.51 (1.35, 1.68) | 1.54 (1.37, 1.74) | |
| High | 2,244 (46.6) | 1,311 (33.3) | 2.20 (1.97, 2.44) | 2.21 (1.97, 2.48) | |
| PRS (per 10 percentile increase) | 1.13 (1.11, 1.15) | 1.13 (1.11, 1.15) | |||
| Healthy lifestyle score | |||||
| 0–2 | 1,519 (31.6) | 876 (22.2) | Ref. | Ref. | |
| 3 | 1,715 (35.6) | 1,337 (33.9) | 0.72 (0.65, 0.81) | 0.78 (0.69, 0.88) | −20.3 (−30.6, −10.0) |
| 4 | 1,233 (25.6) | 1,175 (29.8) | 0.57 (0.51, 0.65) | 0.63 (0.55, 0.72) | −37.8 (−49.7, −25.9) |
| 5 | 347 (7.2) | 553 (14.0) | 0.33 (0.28, 0.39) | 0.38 (0.32, 0.46) | −79.2 (−97.3, −61.1) |
| Per 1-point increase | 0.74 (0.71, 0.78) | 0.78 (0.74, 0.81) | −20.3 (−25.0, −15.7) | ||
| P value for interaction between PRS and healthy lifestyle score4 = 0.88/0.39 | |||||
1Adjusted for age and gender. 2Additionally adjusted for school education, family history of CRC, history of colonoscopy, participation in routine health check-ups, use of nonsteroidal anti-inflammatory drugs, healthy lifestyle score (categorical variable, for the analysis of PRS), and PRS (continuous variable with per 10 percentile increase, for the analysis of healthy lifestyle score). 3PRS was categorized into low, moderate, and high levels according to tertiles of PRS among controls. 4Interactions were tested by inclusion of a cross-product of the PRS (categorical variable/continuous variable) and the healthy lifestyle score (categorical variable) along with the main effect terms in multivariable models. CI, confidence intervals; CRC, colorectal cancer; OR, odds ratio; PRS, polygenic risk score; Ref., reference.