Table 1.
Baseline characteristics in breast cancer survivors and cancer-free women in CLUE II
| Characteristic | Cancer-free women (n = 3140) | Survivors (n = 628) |
|---|---|---|
| Age at index date, mean (SD), y | 64.4 (11.8) | 64.5 (11.8) |
| White, No. (%) | 3089 (98.4) | 622 (99.0) |
| Education, No. (%) | ||
| <12 y | 652 (20.8) | 118 (18.8) |
| 12 y | 1523 (48.5) | 290 (46.2) |
| >12 y | 964 (30.7) | 220 (35.0) |
| Missing | 1 (0.03) | 0 (0.0) |
| Postmenopausal, No. (%) | 1777 (56.6) | 369 (58.8) |
| Body mass index, mean (SD), kg/m2 | 26.1 (5.1) | 26.5 (5.4) |
| Smoking status, No. (%) | ||
| Never | 1919 (61.1) | 388 (61.8) |
| Former | 672 (21.4) | 149 (23.7) |
| Current | 549 (17.5) | 91 (14.5) |
| Missing | 0 (0.0) | 0 (0.0) |
| Alcohol intake, No. (%) | ||
| Never or <1 drink/mo | 1614 (51.4) | 323 (51.4) |
| 1-3 drinks/mo | 382 (12.2) | 82 (13.1) |
| ≥1 drinks/wk | 1027 (32.7) | 202 (32.2) |
| Missing | 117 (3.7) | 21 (3.3) |
| Oral contraceptive use, No. (%) | ||
| Never | 1910 (60.8) | 396 (63.1) |
| Former | 998 (31.8) | 183 (29.1) |
| Current | 196 (6.2) | 42 (6.7) |
| Missing | 36 (1.1) | 7 (1.1) |
| Hormone use, No. (%) | ||
| Never | 2515 (80.1) | 503 (80.1) |
| Former | 132 (4.2) | 24 (3.8) |
| Current estrogen only | 286 (9.1) | 49 (7.8) |
| Current estrogen + progesterone or progesterone only | 100 (3.2) | 26 (4.1) |
| Missing | 107 (3.4) | 26 (4.1) |
| Systolic blood pressure, mean (SD), mmHg | 125.9 (35.6) | 126.3 (38.6) |
| Diastolic blood pressure, mean (SD), mmHg | 79.2 (34.1) | 79.9 (37.9) |
| Plasma total cholesterol, mean (SD), mg/dL | 228.0 (119.3) | 223.5 (96.8) |
| Current medication use, No. (%) | ||
| High–blood pressure medication | 603 (19.2) | 117 (18.6) |
| High-cholesterol medication | 139 (4.4) | 24 (3.8) |
| CVD medication | 784 (25.0) | 149 (23.7) |
| Diabetes medication | 66 (2.1) | 14 (2.2) |
| Year of breast cancer diagnosis, median (25th-75th percentile) | —a | 2002 (1996-2009) |
| Breast cancer stage, No. (%) | ||
| I | — | 375 (59.7) |
| II or III | — | 244 (38.9) |
| Unknown or missing | — | 9 (1.4) |
| Estrogen receptor status, No. (%) | ||
| Positive | — | 463 (73.7) |
| Negative | — | 105 (16.7) |
| Unknown or missing | — | 60 (9.6) |
| Vital status at end of study follow-up,b,c,d No. (%) | ||
| Death from any cause | 699 (22.3) | 217 (34.6) |
| Death from breast cancer | 0 (0.0) | 64 (10.2) |
| Death from cancer (non-breast cancer) | 118 (3.8) | 25 (4.0) |
| Death from CVD | 205 (6.5) | 44 (7.0) |
| Death from non-CVD | 494 (15.7) | 173 (27.6) |
| Administrative censoring (alive at end of follow-up) | 2441 (77.7) | 411 (65.4) |
a
Not applicable to cancer-free women. CVD = cardiovascular disease.
b
Vital status as of December 31, 2015.
c
Among 699 deaths in cancer-free women, 29% due to CVD-related disease (n = 205) and 17% due to non-breast cancer (n = 118).
d
Among 217 deaths in breast cancer survivors, 29% due to breast cancer (n = 64), 20% due to CVD-related disease (n = 44), and 12% due to non-breast cancer (n = 25).