Table 1 Distribution of demographic, reproductive, and lifestyle risk factors by race/ethnicity in the combined LACE and Pathways Studies (n = 2544)
From: Epidemiology of breast cancer subtypes in two prospective cohort studies of breast cancer survivors
| Â | White Total n = 1943 n (%) | African American Total n = 155 n (%) | Asian Total n = 189 n (%) | Hispanic Total n = 197 n (%) | Other Total n = 54 n (%) | Pvaluea |
|---|---|---|---|---|---|---|
Age at diagnosis (years) | Â | Â | Â | Â | Â | < 0.0001 |
   < 50 | 389 (20.0) | 43 (27.7) | 61 (32.3) | 67 (34.0) | 13 (24.1) |  |
   50 to 64 | 879 (45.2) | 80 (51.6) | 87 (46.0) | 80 (40.6) | 29 (53.7) |  |
   ≥ 65 | 675 (34.7) | 32 (20.6) | 41 (21.7) | 50 (25.4) | 12 (22.2) |  |
   mean (± standard deviation) | 59.8 (11.2) | 56.2 (10.7) | 54.8 (11.0) | 55.7 (12.4) | 57.7 (9.8) |  |
Menopausal status | Â | Â | Â | Â | Â | < 0.0001 |
   Postmenopausal | 1,330 (75.6) | 90 (71.4) | 104 (59.1) | 117 (65.4) | 35 (72.9) |  |
   Premenopausal | 430 (24.4) | 36 (28.6) | 72 (40.9) | 62 (34.6) | 13 (27.1) |  |
Family history | Â | Â | Â | Â | Â | 0.001 |
   No | 1,503 (77.4) | 133 (85.8) | 163 (86.2) | 167 (84.8) | 41 (75.9) |  |
   Yes | 440 (22.6) | 22 (14.2) | 26 (13.8) | 30 (15.2) | 13 (24.1) |  |
Parity | Â | Â | Â | Â | Â | 0.006 |
   Nulliparous | 343 (17.7) | 22 (14.2) | 46 (24.3) | 31 (15.7) | 9 (16.7) |  |
   1 to 2 children | 894 (46.0) | 67 (43.2) | 93 (49.2) | 79 (40.1) | 31 (57.4) |  |
   ≥ 3 children | 706 (36.3) | 66 (42.6) | 50 (26.5) | 87 (44.2) | 14 (25.9) |  |
Age at first full-term pregnancy (years) | Â | Â | Â | Â | Â | < 0.0001 |
   Nulliparous | 343 (17.7) | 22 (14.3) | 46 (24.3) | 31 (15.8) | 9 (16.7) |  |
   < 26 | 1,020 (52.6) | 113 (73.4) | 61 (32.3) | 119 (60.7) | 28 (51.9) |  |
   ≥ 26 | 578 (29.8) | 19 (12.3) | 82 (43.4) | 46 (23.5) | 17 (31.5) |  |
Lifetime duration of lactation | Â | Â | Â | Â | Â | 0.215 |
   Never | 908 (47.3) | 92 (59.7) | 81 (44.3) | 91 (48.1) | 25 (47.2) |  |
   0 to 3 months | 279 (14.5) | 19 (12.3) | 31 (16.9) | 25 (13.2) | 8 (15.1) |  |
   ≥ 4 months | 733 (38.2) | 43 (27.9) | 71 (38.8) | 73 (38.6) | 20 (37.7) |  |
Alcohol use | Â | Â | Â | Â | Â | < 0.0001 |
   Never | 675 (39.9) | 77 (67.5) | 116 (75.3) | 93 (62.4) | 28 (57.1) |  |
   Ever | 1,016 (60.1) | 37 (32.5) | 38 (24.7) | 56 (37.6) | 21 (42.9) |  |
Smoking history (years) | Â | Â | Â | Â | Â | < 0.0001 |
   Never | 925 (48.0) | 73 (47.4) | 148 (78.3) | 113 (57.4) | 22 (40.7) |  |
   ≤ 10 | 269 (14.0) | 17 (11.0) | 13 (6.9) | 33 (16.8) | 6 (11.1) |  |
   11 to 19 | 169 (8.8) | 10 (6.5) | 8 (4.2) | 6 (3.0) | 5 (9.3) |  |
   ≥ 20 | 563 (29.2) | 54 (35.1) | 20 (10.6) | 45 (22.8) | 21 (38.9) |  |
Hormone replacement therapy (postmenopausal women only) | Â | Â | Â | Â | Â | Â |
   Never | 310 (23.8) | 37 (42.1) | 47 (45.6) | 37 (32.2) | 12 (34.3) |  |
   Ever | 994 (76.2) | 51 (57.9) | 56 (54.4) | 78 (67.8) | 23 (65.7) |  |
Oral contraceptive use | Â | Â | Â | Â | Â | < 0.0001 |
   Never | 638 (33.8) | 40 (26.7) | 100 (55.9) | 72 (37.7) | 16 (30.2) |  |
   Ever | 1,252 (66.2) | 110 (73.3) | 79 (44.1) | 119 (62.3) | 37 (69.8) |  |
Body mass index (kg/m2)b | Â | Â | Â | Â | Â | < 0.0001 |
   < 25 | 835 (43.4) | 31 (20.0) | 119 (63.3) | 63 (32.5) | 20 (37.0) |  |
   25 to 29 | 600 (31.1) | 48 (31.0) | 46 (24.5) | 64 (33.0) | 14 (25.9) |  |
   ≥ 30 | 491 (25.5) | 76 (49.0) | 23 (12.2) | 67 (34.5) | 20 (37.0) |  |