Table 2.
RR of Invasive Breast cancer for Doubling of Hormone Levels
| Hormone | Hormones Included Individually |
Hormones Included Simultaneously |
Hormones Selected Using Stepwise Regression |
|||
|---|---|---|---|---|---|---|
| RR | 95% CI | RR | 95% CI | RR | 95% CI | |
| Estrone | 1.33 | 1.14 to 1.54 | 1.04 | 0.84 to 1.29 | — | — |
| Estradiol | 1.30 | 1.13 to 1.49 | 0.99 | 0.80 to 1.23 | — | — |
| Estrone sulfate | 1.37 | 1.22 to 1.54 | 1.28 | 1.08 to 1.51 | 1.33 | 1.17 to 1.51 |
| Testosterone | 1.29 | 1.09 to 1.53 | 1.16 | 0.94 to 1.43 | 1.15 | 0.96 to 1.37 |
| DHEAS | 1.15 | 1.04 to 1.29 | 0.99 | 0.87 to 1.13 | — | — |
| SHBG | 0.82 | 0.70 to 0.95 | 0.90 | 0.76 to 1.08 | — | — |
| Prolactin | 1.24 | 1.04 to 1.47 | 1.22 | 1.02 to 1.46 | 1.22 | 1.02 to 1.46 |
NOTE. Multivariable models adjusted for fasting status (< 8 v ≥ 8 hours), time of day (24-hour clock: < 8v 8 to 12 v 13 to 24), age at blood draw (continuous), and season of blood draw (May to October v other month). Entry P < .15 for forward steps and remain P < .20 for backward steps in stepwise regression models.
Abbreviations: DHEAS, dehydroepiandrosterone sulfate; RR, relative risk; SHBG, sex hormone–binding globulin.