TABLE 4.
Association between long-chain ω-3 PUFAs and endometrial cancer risk, stratified by BMI
| Energy-adjusted quintiles of fatty acid intake |
P-trend1 | |||||
| 1 | 2 | 3 | 4 | 5 | ||
| ω-3 from diet | ||||||
| EPA, 20:5ω-3 (mg/d) | ≤18 | 19–35 | 36–54 | 55–84 | >84 | |
| BMI <25 kg/m2 | 1.00 (reference)2 | 0.71 (0.32, 1.54) | 0.57 (0.25, 1.28) | 0.60 (0.27, 1.31) | 0.42 (0.18, 0.99) | 0.052 |
| BMI ≥25 kg/m2 | 1.00 (reference) | 1.53 (0.88, 2.68) | 1.46 (0.82, 2.60) | 1.49 (0.83, 2.66) | 2.62 (1.55, 4.41) | <0.001 |
| P-interaction3 | 0.004 | |||||
| DHA, 22:6ω-3 (mg/d) | ≤40 | 41–71 | 72–109 | 110–171 | >171 | |
| BMI <25 kg/m2 | 1.00 (reference) | 0.62 (0.27, 1.44) | 0.90 (0.43, 1.90) | 0.53 (0.23, 1.20) | 0.35 (0.14, 0.85) | 0.023 |
| BMI ≥25 kg/m2 | 1.00 (reference) | 1.43 (0.81, 2.52) | 1.54 (0.88, 2.71) | 1.52 (0.85, 2.72) | 2.60 (1.53, 4.40) | <0.001 |
| P-interaction3 | 0.002 | |||||
| EPA + DHA (mg/d) | ≤60 | 61–106 | 107–164 | 165–256 | >256 | |
| BMI <25 kg/m2 | 1.00 (reference) | 0.87 (0.39, 1.94) | 0.69 (0.30, 1.55) | 0.72 (0.33, 1.58) | 0.39 (0.16, 0.97) | 0.046 |
| BMI ≥25 kg/m2 | 1.00 (reference) | 1.71 (0.98, 3.00) | 1.48 (0.82, 2.65) | 1.60 (0.89, 2.89) | 2.75 (1.62, 4.68) | <0.001 |
| P-interaction3 | 0.004 | |||||
| ω-3 from diet plus supplement | ||||||
| EPA, 20:5ω-3 (mg/d) | ≤20 | 21–38 | 39–60 | 61–105 | >105 | |
| BMI <25 kg/m2 | 1.00 (reference) | 0.64 (0.30, 1.37) | 0.45 (0.20, 1.02) | 0.66 (0.32, 1.35) | 0.19 (0.07, 0.54) | <0.001 |
| BMI ≥25 kg/m2 | 1.00 (reference) | 1.50 (0.88, 2.57) | 1.43 (0.82, 2.50) | 1.34 (0.75, 2.38) | 2.11 (1.26, 3.55) | 0.016 |
| P-interaction3 | 0.002 | |||||
| DHA, 22:6ω-3 (mg/d) | ≤43 | 44–75 | 76–118 | 119–191 | >191 | |
| BMI <25 kg/m2 | 1.00 (reference) | 0.47 (0.20, 1.10) | 0.82 (0.40, 1.65) | 0.38 (0.16, 0.88) | 0.28 (0.12, 0.68) | 0.005 |
| BMI ≥25 kg/m2 | 1.00 (reference) | 1.29 (0.75, 2.23) | 1.28 (0.73, 2.22) | 1.36 (0.78, 2.37) | 2.09 (1.25, 3.50) | 0.009 |
| P-interaction3 | 0.002 | |||||
| EPA + DHA (mg/d) | ≤65 | 66–115 | 116–181 | 182–298 | >299 | |
| BMI <25 kg/m2 | 1.00 (reference) | 0.57 (0.26, 1.25) | 0.55 (0.26, 1.20) | 0.57 (0.27, 1.21) | 0.29 (0.12, 0.70) | 0.012 |
| BMI ≥25 kg/m2 | 1.00 (reference) | 1.38 (0.80, 2.36) | 1.18 (0.67, 2.07) | 1.44 (0.83, 2.50) | 2.04 (1.22, 3.42) | 0.011 |
| P-interaction3 | 0.004 | |||||
1
Calculated by treating ordinal exposure variables as continuous in regression models. Adjusted for age (time variable), race, education, BMI, pack-years of smoking, physical activity, alcohol consumption, age at menarche, age at first birth, age at menopause, parity, years of combined hormone therapy, years of estrogen-only therapy, years of oral contraceptive use, oophoerectomy, family history of uterine cancer, family history of ovarian cancer, history of diabetes, and total energy.
2
HR; 95% CI in parentheses (all such values). Values are derived from Cox proportional hazards regression models.
3
Calculated by using the likelihood ratio test.