Table 1 Descriptive characteristics of women in the Breast Cancer Prospective Family Study Cohort (ProF-SC) by smoking status and alcohol consumption
|  | Non-smoker (N = 10,158) | Former smoker (N = 4675) | Current smoker (N = 2602) | Non-regular drinker (N = 8817) | Regular drinker (N = 8618) | Total cohort (N = 17,435) |
|---|---|---|---|---|---|---|
Age at baseline (mean, SD) | 46.5 ± 15.6 | 49.2 ± 14.2 | 43.6 ± 14.0 | 48.0 ± 15.7 | 45.5 ± 14.3 | 46.8 ± 15.1 |
Age at breast cancer diagnosis (mean, SD) | 55.9 ± 12.2 | 58.2 ± 12.3 | 52.9 ± 11.5 | 57.0 ± 12.2 | 55.5 ± 12.3 | 56.2 ± 12.3 |
BOADICEA full lifetime risk score, % (mean, SD) | 23.8 ± 17.2 | 22.7 ± 15.4 | 23.3 ± 16.3 | 23.6 ± 17.1 | 23.2 ± 16.0 | 23.4 ± 16.6 |
BOADICEA 1-year risk score, % (mean, SD) | 0.5 ± 0.6 | 0.5 ± 0.6 | 0.4 ± 0.6 | 0.5 ± 0.7 | 0.4 ± 0.6 | 0.5 ± 0.6 |
BOADICEA 5-year risk score, % (mean, SD) | 2.4 ± 3.1 | 2.6 ± 3.1 | 2.2 ± 2.8 | 2.5 ± 3.2 | 2.4 ± 2.9 | 2.4 ± 3.0 |
Body mass index, kg/m2 (mean, SD) | 25.8 ± 5.6 | 26.3 ± 5.7 | 25.3 ± 5.7 | 26.5 ± 5.9 | 25.2 ± 5.3 | 25.8 ± 5.7 |
Cigarette smoking variables | ||||||
 Age at smoking initiation, years (mean, SD) | NA | 18.7 ± 5.2 | 18.1 ± 5.4 | 18.9 ± 6.0 | 18.3 ± 4.8 | 18.5 ± 5.3 |
 Smoking duration, years smoked (mean, SD) | NA | 14.5 ± 11.6 | 23.9 ± 13.4 | 19.0 ± 13.6 | 17.0 ± 12.7 | 17.7 ± 13.1 |
 Smoking intensity, cigarettes/day (mean, SD) | NA | 13.1 ± 10.8 | 15.1 ± 9.3 | 14.0 ± 10.6 | 13.7 ± 10.1 | 13.8 ± 10.3 |
Smoking intensity, cigarettes/day (n, %) | ||||||
 Non-smokera | 10,158 (100.0) | NA | NA | 6286 (71.3) | 3872 (44.9) | 10,158 (58.3) |
 1 to < 5 cig/day | NA | 992 (21.2) | 242 (9.3) | 413 (4.7) | 821 (9.5) | 1234 (7.1) |
 5 to < 10 cig/day | NA | 888 (19.0) | 421 (16.2) | 440 (5.0) | 869 (10.1) | 1309 (7.5) |
 10 to < 20 cig/day | NA | 1321 (28.3) | 936 (36.0) | 823 (9.3) | 1434 (16.6) | 2257 (13.0) |
 ≥ 20 more cig/day | NA | 1434 (30.7) | 980 (37.7) | 830 (9.4) | 1584 (18.4) | 2414 (13.9) |
 Missing | 0 | 40 (0.9) | 23 (0.9) | 25 (0.3) | 38 (0.4) | 63 (0.4) |
Smoking duration, years smoked (n, %) | ||||||
 Non-smoker | 10,158 (100.0) | NA | NA | 6286 (71.3) | 3872 (44.9) | 10,158 (58.3) |
 < 10 years | NA | 1900 (40.6) | 388 (14.9) | 728 (8.3) | 1560 (18.1) | 2288 (13.1) |
 10 to < 20 years | NA | 1367 (29.2) | 582 (22.4) | 621 (7.0) | 1328 (15.4) | 1949 (11.2) |
 20 to < 30 years | NA | 701 (15.0) | 646 (24.8) | 507 (5.8) | 840 (9.8) | 1347 (7.7) |
 ≥ 30 years | NA | 622 (13.3) | 821 (31.6) | 585 (6.6) | 858 (10.0) | 1443 (8.3) |
 Missing | 0 | 85 (1.8) | 165 (6.3) | 90 (1.0) | 160 (1.9) | 250 (1.4) |
Alcohol consumption variables | ||||||
 Total drinks per week (mean, SD) | 6.0 ± 7.0 | 8.0 ± 10.1 | 10.9 ± 14.0 | NA | 7.7 ± 10.0 | 7.7 ± 10.0 |
 Age at drinking initiation (mean, SD) | 25.5 ± 11.0 | 23.7 ± 9.8 | 22.8 ± 8.6 | NA | 24.4 ± 10.2 | 24.4 ± 10.2 |
 Drinking duration, years (mean, SD) | 15.2 ± 12.0 | 18.8 ± 12.9 | 16.0 ± 11.8 | NA | 16.6 ± 12.4 | 16.6 ± 12.4 |
Categorical drinks per week (n, %) | ||||||
 Non-regular drinkerc | 6406 (63.1) | 1686 (36.1) | 986 (37.9) | 8817 (100%) | 261 (3.0)c | 9078 (52.1) |
 < 7 drinks/week | 2420 (23.8) | 1654 (35.4) | 763 (29.3) | NA | 4837 (56.1) | 4837 (27.7) |
 ≥ 7 drinks/week | 1095 (10.8) | 1158 (24.8) | 725 (27.9) | NA | 2978 (34.6) | 2978 (17.1) |
 Missing | 237 (2.3) | 177 (3.8) | 128 (4.9) | NA | 542 (6.3) | 542 (3.1) |
BRCA mutation carriers | ||||||
 Non-carrier | 9374 (92.3) | 4405 (94.2) | 2430 (93.4) | 8148 (92.4) | 8061 (93.5) | 16,209 (93.0) |
 BRCA1 carrier | 417 (4.1) | 156 (3.3) | 105 (4.0) | 366 (4.2) | 312 (3.6) | 678 (3.9) |
 BRCA2 carrier | 367 (3.6) | 114 (2.4) | 67 (2.6) | 303 (3.4) | 245 (2.8) | 548 (3.1) |
Study center | ||||||
 Philadelphia | 444 (4.4) | 246 (5.3) | 94 (3.6) | 420 (4.8) | 364 (4.2) | 784 (4.5) |
 New York | 1211 (11.9) | 616 (13.2) | 171 (6.6) | 1074 (12.2) | 924 (10.7) | 1998 (11.5) |
 Utah | 666 (6.6) | 64 (1.4) | 38 (1.5) | 617 (7.0) | 151 (1.8) | 768 (4.4) |
 Australia | 2147 (21.1) | 1046 (22.4) | 725 (27.9) | 1864 (21.1) | 2054 (23.8) | 3918 (22.5) |
 Ontario, Canada | 1241 (12.2) | 703 (15.0) | 418 (16.1) | 1160 (13.2) | 1202 (14.0) | 2362 (13.6) |
 Northern California | 1892 (18.6) | 679 (14.5) | 380 (14.6) | 1924 (21.8) | 1027 (11.9) | 2951 (16.9) |
 kConFab | 2557 (25.2) | 1321 (28.3) | 776 (29.8) | 1758 (19.9) | 2896 (33.6) | 4654 (26.7) |
Birth cohort | ||||||
 < 1950 | 3917 (38.6) | 2108 (45.1) | 797 (30.6) | 3795 (43.0) | 3027 (35.1) | 6822 (39.1) |
 1950–1959 | 2291 (22.6) | 1151 (24.6) | 666 (25.6) | 1975 (22.4) | 2133 (24.8) | 4108 (23.6) |
 1960–1969 | 2002 (19.7) | 904 (19.3) | 638 (24.5) | 1590 (18.0) | 1954 (22.7) | 3544 (20.3) |
 ≥ 1970 | 1948 (19.2) | 512 (11.0) | 501 (19.3) | 1457 (16.5) | 1504 (17.5) | 2961 (17.0) |
Race | ||||||
 Non-Hispanic White | 7803 (76.8) | 3998 (85.5) | 2158 (82.9) | 6397 (72.6) | 7562 (87.8) | 13,959 (80.1) |
 Non-Hispanic Black | 481 (4.7) | 170 (3.6) | 158 (6.1) | 499 (5.7) | 310 (3.6) | 809 (4.6) |
 Hispanic | 1012 (10.0) | 287 (6.1) | 137 (5.3) | 1057 (12.0) | 379 (4.4) | 1436 (8.2) |
 Asian | 569 (5.6) | 64 (1.4) | 32 (1.2) | 545 (6.2) | 120 (1.4) | 665 (3.8) |
 Other | 244 (2.4) | 135 (2.9) | 94 (3.6) | 271 (3.1) | 202 (2.3) | 473 (2.7) |
 Missing | 49 (0.5) | 21 (0.5) | 23 (0.9) | 48 (0.5) | 45 (0.5) | 93 (0.5) |
Education | ||||||
 High school graduate or less | 3161 (18.1) | 1515 (8.7) | 1139 (6.5) | 3391 (38.5) | 2424 (28.1) | 5815 (33.4) |
 Some college/vocational school | 3656 (21.0) | 1838 (10.5) | 1106 (6.3) | 3166 (35.9) | 3434 (39.9) | 6600 (37.9) |
 Bachelor’s/graduate degree | 3296 (18.9) | 1311 (7.5) | 342 (2.0) | 2213 (25.1) | 2736 (31.8) | 4949 (28.4) |
 Missing | 45 (0.3) | 11 (0.1) | 15 (0.1) | 47 (0.5) | 24 (0.3) | 71 (0.4) |
Parity (number of full-term pregnancies/breastfeeding history) | ||||||
 Nulliparous | 2617 (15.0) | 871 (5.0) | 660 (3.8) | 1857 (21.1) | 2291 (26.6) | 4148 (23.8) |
 Parous 1–2/no breastfeeding | 1037 (6.0) | 586 (3.4) | 410 (2.4) | 1140 (12.9) | 893 (10.4) | 2033 (11.7) |
 Parous 1–2/breastfed | 2626 (15.1) | 1395 (8.0) | 667 (3.8) | 2085 (23.7) | 2603 (30.2) | 4688 (26.9) |
 Parous 3+/no breastfeeding | 758 (4.4) | 390 (2.2) | 256 (1.5) | 854 (9.7) | 550 (6.4) | 1404 (8.1) |
 Parous 3+/breastfed | 3047 (17.5) | 1387 (8.0) | 591 (3.4) | 2820 (32.0) | 2205 (25.6) | 5025 (28.8) |
 Missing | 73 (0.4) | 46 (0.3) | 18 (0.1) | 61 (0.7) | 76 (0.9) | 137 (0.8) |
Hormonal birth control us | ||||||
 Never | 2832 (16.2) | 933 (5.4) | 469 (2.7) | 2756 (31.3) | 1478 (17.2) | 4234 (24.3) |
 Former | 5825 (33.4) | 3194 (18.3) | 1722 (9.9) | 5017 (56.9) | 5724 (66.4) | 10,741 (61.6) |
 Current | 1424 (8.2) | 513 (2.9) | 393 (2.3) | 970 (11.0) | 1360 (15.8) | 2330 (13.4) |
 Missing | 77 (0.4) | 35 (0.2) | 18 (0.1) | 74 (0.8) | 56 (0.7) | 130 (0.8) |