Table 3.
Risk ratios for postmenopausal estrogen receptor-positive breast cancer, by quartiles of biomarker concentrations
| Quartilesa of Normalized Biomarker Concentrations | Cases | Subcohort Non-Cases | Risk Ratio | 95% CI |
|---|---|---|---|---|
| Progesterone | ||||
| Quartile 1 | 72 | 208 | Ref | Ref |
| Quartile 2 | 92 | 218 | 1.25 | (0.87, 1.81) |
| Quartile 3 | 67 | 220 | 0.96 | (0.65, 1.41) |
| Quartile 4 | 111 | 219 | 1.56 | (1.09, 2.24) |
| Androstenedione | ||||
| Quartile 1 | 72 | 214 | Ref | Ref |
| Quartile 2 | 97 | 214 | 1.32 | (0.92, 1.90) |
| Quartile 3 | 69 | 219 | 0.92 | (0.63, 1.35) |
| Quartile 4 | 104 | 219 | 1.39 | (0.97, 2.00) |
| DHEA | ||||
| Quartile 1 | 65 | 216 | Ref | Ref |
| Quartile 2 | 75 | 207 | 1.19 | (0.82, 1.74) |
| Quartile 3 | 94 | 224 | 1.38 | (0.94, 2.00) |
| Quartile 4 | 108 | 219 | 1.55 | (1.06, 2.25) |
| Total Testosterone | ||||
| Quartile 1 | 80 | 211 | Ref | Ref |
| Quartile 2 | 85 | 216 | 1.04 | (0.73, 1.49) |
| Quartile 3 | 98 | 223 | 1.16 | (0.82, 1.65) |
| Quartile 4 | 79 | 216 | 1.04 | (0.72, 1.50) |
| Free Testosterone | ||||
| Quartile 1 | 75 | 218 | Ref | Ref |
| Quartile 2 | 78 | 203 | 1.08 | (0.75, 1.55) |
| Quartile 3 | 83 | 225 | 1.02 | (0.71, 1.47) |
| Quartile 3 | 106 | 220 | 1.26 | (0.89, 1.80) |
| Estrone | ||||
| Quartile 1 | 79 | 207 | Ref | Ref |
| Quartile 2 | 78 | 214 | 0.95 | (0.66, 1.37) |
| Quartile 3 | 86 | 223 | 1.03 | (0.72, 1.48) |
| Quartile 4 | 99 | 220 | 1.13 | (0.78, 1.64) |
| Total Estradiol | ||||
| Quartile 1 | 64 | 215 | Ref | Ref |
| Quartile 2 | 81 | 212 | 1.27 | (0.87, 1.85) |
| Quartile 3 | 93 | 218 | 1.41 | (0.97, 2.05) |
| Quartile 4 | 103 | 214 | 1.49 | (1.01, 2.19) |
| Free Estradiol | ||||
| Quartile 1 | 67 | 216 | Ref | Ref |
| Quartile 2 | 64 | 214 | 0.95 | (0.64, 1.41) |
| Quartile 3 | 101 | 213 | 1.46 | (1.01, 2.12) |
| Quartile 4 | 109 | 216 | 1.47 | (0.99, 2.17) |
| SHBG | ||||
| Quartile 1 | 112 | 215 | Ref | Ref |
| Quartile 2 | 83 | 213 | 0.79 | (0.56, 1.10) |
| Quartile 3 | 72 | 224 | 0.67 | (0.47, 0.95) |
| Quartile 4 | 75 | 214 | 0.83 | (0.57, 1.21) |
CI: Confidence interval. Ref: Reference category. DHEA: Dehydroepiandrosterone. SHBG: Sex-hormone binding globulin.
Quartiles based on the distribution of normalized biomarker values in the subcohort. Minimum, median and maximum values for each quartile are presented in Online Resource 11.
Results were adjusted for sociodemographic and lifestyle confounders (education, socioeconomic disadvantage, Southern European Migrant status, dietary intake of carotenoids at baseline, dietary intake of calcium at baseline, lifestyle alcohol consumption at baseline, smoking status at baseline, adiposity at baseline, physical activity at the second follow-up wave and age at blood collection).