Table 1.
Characteristics of Premenopausal Women Recruited During Annual Screening Mammogram across Volumetric Percent Density Categoriesa
| Almost entirely fatty < 3.5% (N = 35) | Scattered areas of fibroglandular density 3.5% ~ 7.5% (N = 314) | Heterogeneously dense > 7.5% ~ 15.5% (N = 197) | Extremely dense > 15.5% (N = 154) | Overall (N = 705) | |
|---|---|---|---|---|---|
| Race | |||||
| White | 23 (65.7%) | 203 (64.6%) | 146 (74.1%) | 130 (84.4%) | 506 (71.8%) |
| Black | 10 (28.6%) | 94 (29.9%) | 41 (20.8%) | 17 (11.0%) | 163 (23.1%) |
| Other | 1 (2.9%) | 15 (4.8%) | 8 (4.1%) | 7 (4.5%) | 31 (4.4%) |
| Missing | 1 (2.9%) | 2 (0.6%) | 2 (1.0%) | 0 (0%) | 5 (0.7%) |
| Age, years | |||||
| Mean (SD) | 46.2 (5.4) | 46.3 (4.4) | 46.0 (4.3) | 45.2 (4.5) | 46.0 (4.5) |
| Age at Menarche, years | |||||
| Mean (SD) | 12.5 (1.6) | 12.4 (1.6) | 12.8 (1.5) | 13.0 (1.6) | 12.7 (1.6) |
| Missing | 1 (2.9%) | 0 (0%) | 1 (0.5%) | 0 (0%) | 2 (0.3%) |
| Body Shape at Age 10 | |||||
| 1&2 | 8 (22.9%) | 95 (30.3%) | 96 (48.7%) | 88 (57.1%) | 290 (41.1%) |
| 3&4 | 15 (42.9%) | 111 (35.4%) | 62 (31.5%) | 49 (31.8%) | 237 (33.6%) |
| 5 | 6 (17.1%) | 44 (14.0%) | 24 (12.2%) | 11 (7.1%) | 85 (12.1%) |
| 6–9 | 6 (17.1%) | 39 (12.4%) | 6 (3.0%) | 1 (0.6%) | 53 (7.5%) |
| Missing | 0 (0%) | 25 (8.0%) | 9 (4.6%) | 5 (3.2%) | 40 (5.7%) |
| BMI, (kg/m2) | |||||
| Mean (SD) | 38.2 (6.8) | 34.0 (6.9) | 27.2 (4.9) | 23.7 (3.7) | 30.0 (7.5) |
| Body Fat, (%) | |||||
| Mean (SD) | 49.4 (5.1) | 45.6 (6.9) | 37.9 (7.3) | 31.3 (7.4) | 40.4 (9.3) |
| Missing | 4 (11.4%) | 14 (4.5%) | 3 (1.5%) | 4 (2.6%) | 25 (3.5%) |
| Parity and Age at First Birth | |||||
| Nulliparous | 7 (20.0%) | 67 (21.3%) | 43 (21.8%) | 43 (27.9%) | 162 (23.0%) |
| 1–2 children, < 25 years | 6 (17.1%) | 65 (20.7%) | 24 (12.2%) | 11 (7.1%) | 107 (15.2%) |
| 1–2 children,25–29 years | 3 (8.6%) | 44 (14.0%) | 36 (18.3%) | 27 (17.5%) | 111 (15.7%) |
| 1–2 children, ≥ 30 years | 11 (31.4%) | 53 (16.9%) | 49 (24.9%) | 43 (27.9%) | 156 (22.1%) |
| ≥ 3 children, < 25 years | 3 (8.6%) | 58 (18.5%) | 15 (7.6%) | 12 (7.8%) | 88 (12.5%) |
| ≥ 3 children, ≥ 25 years | 5 (14.3%) | 25 (8.0%) | 30 (15.2%) | 18 (11.7%) | 79 (11.2%) |
| Missing | 0 (0%) | 2 (0.6%) | 0 (0%) | 0 (0%) | 2 (0.3%) |
| Family History of Breast Cancer | |||||
| No | 29 (82.9%) | 251 (79.9%) | 152 (77.2%) | 104 (67.5%) | 540 (76.6%) |
| Yes | 5 (14.3%) | 57 (18.2%) | 44 (22.3%) | 46 (29.9%) | 152 (21.6%) |
| Missing | 1 (2.9%) | 6 (1.9%) | 1 (0.5%) | 4 (2.6%) | 13 (1.8%) |
| Oral Contraceptive Use, years | |||||
| No | 5 (14.3%) | 42 (13.4%) | 18 (9.1%) | 16 (10.4%) | 82 (11.6%) |
| < 1 year | 2 (5.7%) | 27 (8.6%) | 13 (6.6%) | 12 (7.8%) | 55 (7.8%) |
| 1–4 years | 9 (25.7%) | 66 (21.0%) | 31 (15.7%) | 35 (22.7%) | 141 (20.0%) |
| 5–9 years | 5 (14.3%) | 59 (18.8%) | 47 (23.9%) | 30 (19.5%) | 143 (20.3%) |
| > 10 years | 14 (40.0%) | 119 (37.9%) | 87 (44.2%) | 60 (39.0%) | 281 (39.9%) |
| Missing | 0 (0%) | 1 (0.3%) | 1 (0.5%) | 1 (0.6%) | 3 (0.4%) |
| Alcohol consumption, /per week | |||||
| 0 drinks | 13 (37.1%) | 107 (34.1%) | 51 (25.9%) | 39 (25.3%) | 211 (29.9%) |
| < 1 drink | 8 (22.9%) | 85 (27.1%) | 55 (27.9%) | 32 (20.8%) | 181 (25.7%) |
| 1–2 drinks | 9 (25.7%) | 55 (17.5%) | 37 (18.8%) | 31 (20.1%) | 133 (18.9%) |
| 3–5 drinks | 4 (11.4%) | 46 (14.6%) | 39 (19.8%) | 37 (24.0%) | 127 (18.0%) |
| 6–10 drinks | 0 (0%) | 18 (5.7%) | 12 (6.1%) | 12 (7.8%) | 43 (6.1%) |
| > 10 drinks | 1 (2.9%) | 3 (1.0%) | 3 (1.5%) | 2 (1.3%) | 9 (1.3%) |
| Missing | 0 (0%) | 0 (0%) | 0 (0%) | 1 (0.6%) | 1 (0.1%) |
| VPD, (%) | |||||
| Mean (SD) | 3.15 (0.3) | 5.16 (1.1) | 10.9 (2.3) | 22.6 (6.2) | 10.5 (7.6) |
| DV, (cm3) | |||||
| Mean (SD) | 57.7 (20.6) | 72.3 (33.5) | 81.7 (41.4) | 108 (62.2) | 82.0 (45.5) |
| NDV, (cm3) | |||||
| Mean (SD) | 1870 (674) | 1470 (690) | 752 (392) | 428 (258) | 1060 (717) |
a. 5 participants are missing VPD category, categories may not equal overall value
Abbreviations: standard deviation (SD), volumetric percent density (VPD), dense volume (DV), non-dense volume (NDV)