Variable | Case (n = 411), n (%) | Control (n = 1,212), n (%) | OR (95% CI) | Pvalue | Adjusted OR (95% CI)* | Pvalue | Adjusted OR (95% CI)‡ | Pvalue |
---|---|---|---|---|---|---|---|---|
Genetic risk score, quartiles (range), mean | Â | Â | Â | Â | Â | Â | Â | Â |
First (32.4-43.6), 40.4 | 80 (19.5) | 326 (26.9) | 1.00 (ref) | Â | 1.00 (ref) | Â | 1.00 (ref) | Â |
Second (43.6-47.1), 45.4 | 96 (23.4) | 310 (25.6) | 1.26 (0.90, 1.75) | 0.178 | 1.25 (0.90, 1.75) | 0.182 | 1.26 (0.90, 1.76) | 0.174 |
Third (47.1-50.6), 48.9 | 109 (26.5) | 296 (24.4) | 1,47 (1.06, 2.04) | 0.020 | 1.49 (1.07, 2.06) | 0.017 | 1.47 (1.06, 2.04) | 0.022 |
Fourth (50.6-65.8), 53.6 | 126 (30.7) | 280 (23.1) | 1.78 (1.29, 2.44) | <0.001 | 1.74 (1.26, 2.40) | 0.001 | 1.75 (1.27, 2.41) | 0.001 |
P trend | Â | Â | 1.21 (1.09, 1.33) | <0.001 | 1.20 (1.09, 1.33) | <0.001 | 1.20 (1.08, 1.33) | <0.001 |
Age at first live birth, years | Â | Â | Â | Â | Â | Â | Â | Â |
<20 | 56 (13.6) | 212 (17.5) | 1.00 (ref) | Â | 1.00 (ref) | Â | 1.00 (ref) | Â |
20-24 | 129 (31.4) | 458 (37.8) | 1.11 (0.77, 1.59) | 0.571 | 1.04 (0.72, 1.50) | 0.823 | 1.05 (0.73, 1.51) | 0.804 |
25-29 or null | 175 (42.6) | 416 (34.3) | 1.67 (1.16, 2.39) | 0.005 | 1.51 (1.04, 2.18) | 0.030 | 1.49 (1.03, 2.15) | 0.036 |
≥30 | 51 (12.4) | 126 (10.4) | 1.62 (1.03, 2.55) | 0.038 | 1.46 (0.92, 2.31) | 0.111 | 1.49 (1.03, 2.29) | 0.131 |
P trend | Â | Â | 1.25 (1.09, 1.42) | 0.001 | 1.20 (1.05, 1.38) | 0.008 | 1.19 (1.04, 1.37) | 0.011 |
Age at menarche, years | Â | Â | Â | Â | Â | Â | Â | Â |
≥14 | 160 (38.9) | 540 (44.6) | 1.00 (ref) |  | 1.00 (ref) |  | 1.00 (ref) |  |
12-13 | 180 (43.8) | 484 (39.9) | 1.29 (1.00, 1.66) | 0.049 | 1.21 (0.93, 1.56) | 0.151 | 1.23 (0.94, 1.60) | 0.126 |
<12 | 71 (17.3) | 188 (15.5) | 1.34 (0.95, 1.89) | 0.097 | 1.20 (0.84, 1.71) | 0.312 | 1.19 (0.83, 1.71) | 0.345 |
P trend | Â | Â | 1.18 (1.00, 1.39) | 0.048 | 1.12 (0.94, 1.32) | 0.208 | 1.11 (0.94, 1.33) | 0.220 |
Family history | Â | Â | Â | Â | Â | Â | Â | Â |
No | 400 (97.3) | 1196 (98.7) | 1.00 (ref) | Â | 1.00 (ref) | Â | 1.00 (ref) | Â |
Yes | 11 (2.7) | 16 (1.3) | 2.11 (0.97, 4.61) | 0.061 | 2.06 (0.94, 4.52) | 0.071 | 1.78 (0.79, 4.00) | 0.162 |
Past breast biopsy, n (%) | Â | Â | Â | Â | Â | Â | Â | Â |
No | 401 (97.6) | 1193 (98.4) | 1.00 (ref) | Â | 1.00 (ref) | Â | 1.00 (ref) | Â |
Yes | 10 (2.4) | 19 (1.6) | 1.55 (0.69, 3.48) | 0.288 | 1.36 (0.60, 3.08) | 0.462 | 1.36 (0.58, 3.20) | 0.475 |
Body mass index, kg/m2 | Â | Â | Â | Â | Â | Â | Â | Â |
<20 | 51 (12.4) | 167 (13.8) | 1.00 (ref) | Â | 1.00 (ref) | Â | 1.00 (ref) | Â |
20 to <24 | 216 (52.6) | 659 (54.4) | 1.09 (0.77, 1.54) | 0.632 | 1.11 (0.78, 1.58) | 0.562 | 1.16 (0.81, 1.66) | 0.423 |
24 to <28 | 102 (24.8) | 305 (25.2) | 1.10 (0.75, 1.62) | 0.610 | 1.12 (0.76, 1.64) | 0.558 | 1.15 (0.78, 1.70) | 0.488 |
28 or higher | 42 (10.2) | 81 (6.7) | 1.74 (1.07, 2.85) | 0.027 | 1.83 (1.12, 3.01) | 0.016 | 1.99 (1.21, 3.29) | 0.007 |
P trend | Â | Â | 1.14 (0.99, 1.31) | 0.067 | 1.15 (1.00, 1.33) | 0.048 | 1.17 (1.02, 1.35) | 0.031 |