Table 2.
Difference in average percent mammographic density [β (95% confidence interval)] by quartile of plasma hormone exposure (maximum n = 631)
| Plasma hormone | Quartiles | p-trend* | ||||
|---|---|---|---|---|---|---|
| 1 | 2 | 3 | 4 | |||
| Estradiol | ||||||
| Follicular (n = 389) | Median, pg/mL | 21.2 | 37.7 | 50.5 | 82.6 | |
| Model 1 | Ref | − 1.6 (− 6.2, 3.1) | 0.5 (− 3.9, 4.8) | 6.3 (1.6, 11.0) | 0.002 | |
| Model 2 | Ref | − 1.1 (− 5.7, 3.5) | 1.3 (− 3.0, 5.6) | 6.7 (2.2, 11.3) | < 0.001 | |
| Luteal (n = 396) | Median, pg/mL | 73.1 | 109.6 | 145.1 | 203.7 | |
| Model 1 | Ref | − 1.2 (− 5.9, 3.5) | 1.5 (− 2.8, 5.8) | 0.3 (− 4.1, 4.6) | 0.68 | |
| Model 2 | Ref | − 2.0 (− 6.5, 2.4) | 1.5 (− 2.6, 5.6) | 0.9 (− 3.6, 5.3) | 0.41 | |
| Estrone | ||||||
| Follicular (n = 395) | Median, pg/mL | 26.1 | 35.5 | 43.9 | 62.1 | |
| Model 1 | Ref | 1.0 (− 3.3, 5.4) | 0.8 (− 3.6, 5.2) | 1.5 (− 3.3, 6.3) | 0.59 | |
| Model 2 | Ref | 1.2 (− 3.0, 5.4) | 2.3 (− 2.2, 6.8) | 2.9 (− 2.0, 7.8) | 0.24 | |
| Luteal (n = 429) | Median, pg/mL | 51.5 | 73.1 | 89.6 | 122.5 | |
| Model 1 | Ref | 0.8 (− 3.3, 5.0) | − 0.1 (− 4.3, 4.1) | 1.5 (− 2.5, 5.5) | 0.53 | |
| Model 2 | Ref | 0.3 (− 3.9, 4.5) | 0.7 (− 3.5, 4.9) | 2.6 (− 1.4, 6.7) | 0.18 | |
| Free estradiol | ||||||
| Follicular (n = 382) | Median, pg/mL | 0.3 | 0.5 | 0.7 | 1.0 | |
| Model 1 | Ref | − 0.5 (− 4.9, 3.9) | − 0.6 (− 5.1, 3.9) | 3.6 (− 1.1, 8.3) | 0.11 | |
| Model 2 | Ref | 0.9 (− 3.4, 5.2) | 0.2 (− 4.1, 4.6) | 5.3 (0.8, 9.8) | 0.02 | |
| Luteal (n = 391) | Median, pg/mL | 0.9 | 1.4 | 1.8 | 2.6 | |
| Model 1 | Ref | 1.0 (− 3.6, 5.6) | − 2.2 (− 6.6, 2.3) | − 0.2 (− 4.4, 4.1) | 0.69 | |
| Model 2 | Ref | 1.2 (− 3.2, 5.6) | − 2.0 (− 6.5, 2.5) | 0.5 (− 3.8, 4.9) | 0.97 | |
| Estrone sulfate | ||||||
| Follicular (n = 269) | Median, pg/mL | 315.4 | 532.9 | 778.0 | 1295.6 | |
| Model 1 | Ref | 0.1 (− 5.5, 5.6) | − 2.6 (− 7.9, 2.8) | − 0.6 (− 6.3, 5.1) | 0.73 | |
| Model 2 | Ref | 1.4 (− 4.1, 7.0) | − 0.7 (− 5.7, 4.3) | 0.8 (− 4.6, 6.2) | 0.94 | |
| Luteal (n = 267) | Median, pg/mL | 649.3 | 1227.2 | 1869.4 | 3427.5 | |
| Model 1 | Ref | 1.1 (− 4.1, 6.4) | 4.7 (− 0.5, 9.9) | − 1.6 (− 6.6, 3.3) | 0.44 | |
| Model 2 | Ref | 2.9 (− 2.5, 8.3) | 5.2 (− 0.3, 10.7) | − 1.3 (− 6.7, 4.1) | 0.37 | |
| Progesterone | ||||||
| Luteal (n = 531) | Median, ng/dL | 324.5 | 991.0 | 1440.8 | 2147.2 | |
| Model 1 | Ref | − 0.3 (− 4.2, 3.5) | − 3.3 (− 7.2, 0.5) | − 3.1 (− 6.9, 0.7) | ** | |
| Model 2 | Ref | 0.7 (− 3.5, 4.8) | − 1.9 (− 5.9, 2.2) | − 1.8 (− 5.9, 2.4) | ** | |
| Testosterone | ||||||
| Average + untimed (n = 630) | Median, ng/dL | 15.1 | 20.8 | 26.4 | 35.0 | |
| Model 1 | Ref | − 1.2 (− 4.7, 2.4) | 2.3 (− 1.3, 5.8) | 0.4 (− 3.0, 3.7) | 0.46 | |
| Model 2 | Ref | − 0.5 (− 3.9, 2.9) | 2.6 (− 0.9, 6.1) | 1.2 (− 2.2, 4.5) | 0.26 | |
| Free testosterone | ||||||
| Average + untimed (n = 624) | Median, ng/dL | 0.11 | 0.16 | 0.21 | 0.32 | |
| Model 1 | Ref | − 3.9 (− 7.6, − 0.2) | − 3.3 (− 7.0, 0.5) | − 5.1 (− 9.1, − 1.1) | 0.03 | |
| Model 2 | Ref | − 3.7 (− 7.2, − 0.2) | − 3.3 (− 7.0, 0.4) | − 4.7 (− 8.7, − 0.8) | 0.04 | |
| Androstenedione | ||||||
| Average + untimed (n = 352) | Median, ng/dL | 61.0 | 85.8 | 106.3 | 147.6 | |
| Model 1 | Ref | 0.4 (− 4.3, 5.1) | 1.4 (− 3.5, 6.3) | − 0.4 (− 5.1, 4.3) | 0.88 | |
| Model 2 | Ref | − 0.1 (− 4.8, 4.6) | 1.3 (− 3.5, 6.1) | 0.1 (− 4.3, 4.6) | 0.91 | |
| DHEA | ||||||
| Luteal + untimed (n = 349) | Median, ng/dL | 386.4 | 544.9 | 712.7 | 1061.6 | |
| Model 1 | Ref | − 0.2 (− 5.0, 4.6) | − 0.3 (− 5.4, 4.8) | 1.7 (− 3.2, 6.7) | 0.44 | |
| Model 2 | Ref | − 0.6 (− 5.5, 4.2) | − 1.3 (− 6.3, 3.7) | 0.9 (− 3.8, 5.6) | 0.63 | |
| DHEAS | ||||||
| Luteal + untimed (n = 508) | Median, μg/dL | 32.6 | 55.8 | 80.0 | 116.9 | |
| Model 1 | Ref | 0.0 (− 4.0, 4.0) | 0.1 (− 3.7, 4.0) | − 0.9 (− 4.9, 3.0) | 0.64 | |
| Model 2 | Ref | − 0.2 (− 4.2, 3.7) | − 0.2 (− 4.0, 3.5) | − 1.9 (− 6.0, 2.2) | 0.36 | |
| SHBG | ||||||
| Luteal + untimed (n = 631) | Median, nmol/L | 35.5 | 54.5 | 74.9 | 106.2 | |
| Model 1 | Ref | − 2.5 (− 6.2, 1.1) | 1.7 (− 2.2, 5.5) | 4.6 (0.8, 8.5) | 0.002 | |
| Model 2 | Ref | − 1.8 (− 5.3, 1.7) | 1.8 (− 2.1, 5.6) | 4.8 (1.1, 8.6) | 0.002 | |
| AMH | ||||||
| Luteal + untimed (n = 230) | Median, pg/mL | 131.0 | 539.9 | 1146.4 | 2806.3 | |
| Model 1 | Ref | − 1.6 (− 7.7, 4.5) | − 6.9 (− 13.1, − 0.6) | − 1.7 (− 8.6, 5.2) | 0.93 | |
| Model 2 | Ref | − 2.5 (− 8.5, 3.5) | − 7.2 (− 13.5, − 0.9) | − 3.3 (− 10.0, 3.5) | 0.60 | |
DHEA dehydroepiandrosterone, DHEAS dehydroepiandrosterone sulfate, SHBG sex hormone–binding globulin, AMH anti-Müllerian hormone
Model 1: adjusted for age, age2 at blood draw, and BMI at blood draw
Model 2: adjusted for age and age2 at blood draw, BMI at blood draw (continuous, kg/m2), age at menarche (< 12, 12, 13, ≥ 14), parity and age at first birth (nulliparous, 1–2 children and < 25 years, 1–2 children and 25–29 years, 1–2 children and ≥ 30 years, 3+ children and < 25 years, 3+ children and ≥ 25 years + missing), family history of breast cancer at blood draw (yes, no), alcohol intake at blood draw (0 g/day, 0.1–4.9 g/day, 5–14.9 g/day, 15 + g/day, missing), luteal day (3–7 days, 8–28 days, missing/untimed)
*Trend test with median value of the quartile
**Significant evidence of non-linearity (p ≤ 0.01); p values for overall significance of curve were < 0.01 for Model 1 and 0.01 for Model 2