Table 3.
Association between urinary level of PGE-M and risk of breast cancer, stratified by menopausal status and BMI
| Overall | BMI <25 | BMI ≥25 | |||||
|---|---|---|---|---|---|---|---|
| PGE-M (ng/mg Cr) | Cases/controls | OR (95% CI) a | Cases/controls | OR (95% CI) a | Cases/controls | OR (95% CI) a | P for interactionb |
| All women | |||||||
| Q1 (<1.99) | 145/270 | 1,00 (ref.) | 98/179 | 1,00 (ref.) | 47/91 | 1,00 (ref.) | |
| Q2 (1.99–2.28) | 118/271 | 0.88 (0.65–1.19) | 82/190 | 0.85 (0.59–1.23) | 36/81 | 1.01 (0.58–1.76) | |
| Q3 (2.29–2.63) | 123/271 | 0.97 (0.71–1.33) | 70/165 | 0.89 (0.60–1.34) | 53/106 | 1.10 (0.66–1.84) | 0.943 |
| Q4 (>2.63) | 118/270 | 1.07 (0.77–1.48) | 59/138 | 1.13 (0.72–1.76) | 59/132 | 0.99 (0.60–1.64) | |
| P for linear trend | 0.609 | 0.691 | 0.977 | ||||
| Postmenopausal women | |||||||
| Q1 (<2.13) | 60/150 | 1.00 (ref.) | 26/88 | 1.00 (ref.) | 34/62 | 1.00 (ref.) | |
| Q2 (2.13–2.42) | 60/149 | 1.02 (0.66–1.58) | 30/87 | 1.06 (0.56–1.99) | 30/62 | 0.98 (0.52–1.85) | |
| Q3 (2.43–2.72) | 53/153 | 1.03 (0.66–1.16) | 31/85 | 1.50 (0.79–2.83) | 22/68 | 0.72 (0.37–1.40) | 0.012 |
| Q4 (>2.72) | 72/151 | 1.39 (0.90–2.15) | 38/73 | 2.32 (1.24–4.41) | 34/78 | 0.88 (0.47–1.63) | |
| P for linear trend | 0.147 | 0.005 | 0.516 | ||||
| Premenopausal women | |||||||
| Q1 (<1.85) | 71/119 | 1.00 (ref.) | 58/85 | 1.00 (ref.) | 21/34 | 1.00 (ref.) | |
| Q2 (1.85–2.11) | 76/121 | 1.11 (0.73–1.69) | 56/94 | 0.87(0.54–1.41) | 20/27 | 2.38 (0.94–6.01) | |
| Q3 (2.12–2.42) | 48/118 | 0.73 (0.46–1.16) | 37/92 | 0.61 (0.36–1.02) | 11/26 | 1.70 (0.60–4.87) | 0.266 |
| Q4 (>2.42) | 64/121 | 1.00 (0.65–1.55) | 33/68 | 0.82 (0.47–1.42) | 31/53 | 1.63 (0.70–3.69) | |
| P for linear trend | 0.589 | 0.198 | 0.622 | ||||
| P for interactionc = 0.021 | |||||||
a
Derived from unconditional logistic regression and adjusted for age (continuous variable), education (< high school or ≥ high school), cigarette smoking status (non-smokers or ever-smokers), number of live births (0, 1, or ≥2), and months of breastfeeding (four levels: < 6.0, 6.0–11.9, 12.0–24.0, and >24.0).
b
P for interaction between urinary PGE-M (continuous variable) and BMI (<25 kg/m2 or ≥25 kg/m2).
c
P for interaction between urinary PGE-M (continuous variable) and menopausal status (premenopausal or postmenopausal).