Table 3.
Risk of breast cancer among postmenopausal women not using hormones in the Nurses' Health Study on the basis of several estrogen and androgen scoresa
| RR (95% CI)b, all casesc | RR (95% CI)b, ER+ casesc | |||
|---|---|---|---|---|
| Hormone scores | Estrogen scores | Androgen scores | Estrogen scores | Androgen scores |
| Number of hormones > geometric meand | ||||
| 0 | 1.0 | 1.0 | 1.0 | 1.0 |
| 1 | 1.5 (1.0 to 2.5) | 1.1 (0.6 to 2.0) | 1.4 (0.8 to 2.6) | 1.2 (0.6 to 2.5) |
| 2 | 1.5 (0.9 to 2.3) | 1.4 (0.8 to 2.5) | 1.6 (0.9 to 2.8) | 1.8 (0.9 to 3.5) |
| 3 or 4 | 1.9 (1.3 to 3.0) | 1.5 (0.9 to 2.3) | 2.2 (1.3 to 3.8) | 1.5 (0.8 to 2.6) |
| Per 1-unit increase | 1.21 (1.06 to 1.38) | 1.12 (1.00 to 1.25) | 1.29 (1.09 to 1.53) | 1.09 (0.95 to 1.25) |
| Per 1 SD increase§ | 1.25 (1.07 to 1.47) | 1.18 (1.00 to 1.40) | 1.36 (1.11 to 1.67) | 1.14 (0.92 to 1.40) |
| P trend | 0.01 | 0.05 | 0.003 | 0.22 |
| Score weighted by individual hormone associationse | ||||
| Quintile 1 | 1.0 | 1.0 | 1.0 | 1.0 |
| Quintile 2 | 1.2 (0.7 to 2.1) | 1.1 (0.7 to 2.0) | 1.2 (0.6 to 2.5) | 1.2 (0.6 to 2.6) |
| Quintile 3 | 1.8 (1.1 to 3.0) | 1.2 (0.7 to 2.1) | 1.7 (0.9 to 3.4) | 1.8 (0.9 to 3.6) |
| Quintile 4 | 1.3 (0.7 to 2.2) | 1.2 (0.7 to 2.1) | 1.3 (0.6 to 2.6) | 1.2 (0.6 to 2.5) |
| Quintile 5 | 2.1 (1.2 to 3.7) | 1.7 (1.0 to 3.0) | 2.4 (1.2 to 4.9) | 2.0 (1.0 to 4.2) |
| Per 1 SD increasee | 1.28 (1.08 to 1.52) | 1.19 (0.99 to 1.42) | 1.38 (1.12 to 1.71) | 1.16 (0.92 to 1.46) |
| P trend | 0.005 | 0.06 | 0.003 | 0.21 |
ER = estrogen receptor. aHormones included in the score are estrone, estradiol, estrone sulfate in the estrogen score and testosterone, androstenedione, dehydroepiandrosterone, dehydroepiandrosterone sulfate in the androgen score. bRR and 95% CI were adjusted for age at blood draw and menopause, parity, history of benign breast disease, family history of breast cancer, fasting status and time of day of blood draw. cn = 265 total cases and n = 147 ER+ cases. dScore is the number of hormones for which the participant had higher than the age- and assay batch-adjusted geometric mean hormone level. Among controls, the estrogen score mean = 1.5 (SD = 1.2) and the androgen score mean = 2.1 (SD = 1.5). eScore is the sum of the log2-transformed hormone level multiplied by the β coefficient for that hormone with breast cancer risk. Among controls, the estrogen score mean = 4.3 (SD = 0.6) and the androgen score mean = 6.0 (SD = 0.7).