Table 2.
Hazard ratio and 95% confidence interval of incident colorectal cancer, overall and by MSI status, according to intake of marine ω-3 polyunsaturated fatty acids in the pooled cohorts of Nurses’ Health Study (1984–2010) and Health Professionals Follow-up Study (1986–2010)*
| Analysis | <0.10g/d | 0.10–0.19g/d | 0.20–0.29g/d | ≥0.30g/d | P trend |
|---|---|---|---|---|---|
| Overall CRC† | |||||
| Person-years | 450 660 | 917 634 | 668 272 | 861 194 | |
| No. of cases (n = 1125) | 177 | 353 | 256 | 339 | |
| Age-adjusted HR (95% CI)‡ | 1.00 (referent) | 0.96 (0.80 to 1.15) | 0.88 (0.73 to 1.07) | 0.83 (0.69 to 1.00) | .01 |
| Multivariable HR (95% CI)§ | 1.00 (referent) | 0.95 (0.79 to 1.15) | 0.89 (0.73 to 1.09) | 0.87 (0.72 to 1.05) | .09 |
| MSS CRC | |||||
| No. of cases (n = 941) | 135 | 300 | 214 | 292 | |
| Age-adjusted HR (95% CI)‡ | 1.00 (referent) | 1.08 (0.88 to 1.33) | 0.97 (0.78 to 1.21) | 0.93 (0.75 to 1.14) | .09 |
| Multivariable HR (95% CI)§ | 1.00 (referent) | 1.08 (0.87 to 1.32) | 0.98 (0.79 to 1.22) | 0.97 (0.78 to 1.20) | .31 |
| MSI-high CRC | |||||
| No. of cases (n = 184) | 42 | 53 | 42 | 47 | |
| Age-adjusted HR (95% CI)‡ | 1.00 (referent) | 0.57 (0.38 to 0.86) | 0.60 (0.39 to 0.93) | 0.52 (0.34 to 0.79) | .02 |
| Multivariable HR (95% CI)§ | 1.00 (referent) | 0.57 (0.38 to 0.86) | 0.61 (0.40 to 0.94) | 0.54 (0.35 to 0.83) | .05 |
| P heterogeneity|| | .007 | .05 | .02 | ||
* All P values are two-sided. CI = confidence interval; CRC = colorectal cancer; HR = hazard ratio; MSI = microsatellite instability; MSS = microsatellite stable.
† Among patients with available MSI data.
‡ Sex-stratified Cox proportional hazards model was used.
§ Additionally adjusted for family history of colorectal cancer, history of endoscopy, pack-years of smoking before age 30 years (in women: 0, 0 to <5, and ≥5; in men: 0, >0 to <10, and ≥10), current smoking status, body mass index (continuous), physical activity (in women: 0 to <5, 5 to <11.5, 11.5 to <22, and ≥22 metabolic equivalents [METs]/week; in men: 0 to <10, 10 to <22.5, 22.5 to <41.5, and ≥41.5 METs/week), multivitamin use, regular use of aspirin or nonsteroidal anti-inflammatory drugs (≥2 tablets/week), alcohol consumption (in women: 0 to <0.15, 0.15 to <2.0, 2.0 to <7.5, and ≥7.5g/d; in men: 0 to <5, 5 to <10, 10 to <15, 15 to <30, and ≥30g/d) and Dietary Approaches to Stop Hypertension score (in quartiles).
|| Likelihood ratio test was used to compare the model that allows for separate associations for MSS and MSI-high tumors to the model that assumes a common association across subtypes.