Table 1.
Characteristics of breast cancer controls in the Asian-American Breast Cancer Study by menopausal status
| Premenopausal women in luteal phase (n = 119) | Postmenopausal women (n = 72) | |||
|---|---|---|---|---|
| |
mean |
s.d. |
mean |
s.d. |
|
Age (y)* |
41.2 |
5.4 |
53.0 |
3.4 |
|
Body Mass Index (kg / m2) |
21.7 |
3.5 |
21.7 |
2.5 |
| |
n |
column % |
n |
column % |
|
Study center, n(%) |
|
|
|
|
| Hawaii |
79 |
66.4% |
48 |
66.7% |
| Los Angeles |
19 |
16.0% |
13 |
18.1% |
| San Francisco |
21 |
17.6% |
11 |
15.3% |
|
Combined parity and age at first birth, n(%) |
|
|
|
|
| Nulliparous |
17 |
14.3% |
11 |
15.3% |
| 1st birth age ≤ 20 y |
7 |
5.9% |
4 |
5.6% |
| 1-2 live births / age ≥ 21 |
73 |
61.3% |
28 |
38.9% |
| 3+ live births / age ≥ 21 |
22 |
18.5% |
29 |
40.3% |
|
Age at menarche, n(%) |
|
|
|
|
| ≤ 12 y |
72 |
60.5% |
30 |
41.7% |
| > 12 y |
47 |
39.5% |
42 |
58.3% |
|
Born in Asia, n (%) |
|
|
|
|
| No |
93 |
78.2% |
57 |
79.2% |
| Yes |
26 |
21.8% |
15 |
20.8% |
|
Soy intake (frequency of weekly intake), n (%) |
|
|
|
|
| 0-0.5 |
35 |
29.4% |
12 |
16.7% |
| 0.5 – 1.0 |
35 |
29.4% |
22 |
30.6% |
| > 1.0 |
49 |
41.2% |
38 |
52.8% |
|
Green tea (frequency of weekly intake), n (%) |
|
|
|
|
| <once weekly |
62 |
52.1% |
25 |
34.7% |
| 1-6 times weekly |
32 |
26.9% |
23 |
31.9% |
| 7+ times weekly |
25 |
21.0% |
24 |
33.3% |
|
Black tea (frequency of weekly intake), n (%) |
|
|
|
|
| <once weekly |
85 |
71.4% |
51 |
70.8% |
| 1-6 times weekly |
21 |
17.6% |
16 |
22.2% |
| 7+ times weekly |
13 |
10.9% |
5 |
6.9% |
|
Coffee (frequency of weekly intake), n (%) |
|
|
|
|
| 0-2 times weekly |
30 |
25.2% |
11 |
15.3% |
| 3-13 times weekly |
39 |
32.8% |
22 |
30.6% |
| ≥14 times weekly |
50 |
42.0% |
39 |
54.2% |
|
Estimated weekly caffeine intake (mg), n (%) |
|
|
|
|
| 0-734 |
41 |
34.5% |
23 |
31.9% |
| 734-1610 |
39 |
32.8% |
23 |
31.9% |
| >1610 | 39 | 32.8% | 26 | 36.1% |