Table 2 Distribution of potential risk factors for breast cancer according to serum T3 level
Factor | T3 quartile | |||
|---|---|---|---|---|
1 | 2 | 3 | All | |
n = 682 | n = 765 | n = 738 | n = 2185 | |
Column percent (T3 levels in italics) | ||||
T3 (mIU/l) | <1.70 | 1.70-1.90 | >1.90 | |
Age | ||||
< 50 | 60.6 | 37.9 | 22.4 | 39.7 |
> 50 | 39.4 | 62.1 | 77.6 | 60.3 |
Education | ||||
<12 years | 55.1 | 55.9 | 62.5 | 57.9 |
12 years | 20.8 | 26.9 | 22.4 | 23.5 |
>12 years | 19.6 | 13.5 | 11.2 | 14.6 |
Missing | 4.4 | 3.7 | 3.9 | 4.0 |
Married | 56.7 | 51.8 | 50.4 | 52.9 |
Missing | 0.7 | 3.8 | 12.6 | 5.8 |
Smoking | ||||
Never | 44.0 | 48.5 | 47.0 | 46.6 |
Current | 35.3 | 33.3 | 33.3 | 34.0 |
Ex | 20.7 | 18.0 | 18.8 | 19.1 |
Missing | - | 0.1 | 0.8 | 0.3 |
Alcohol consumption | ||||
Nothing | 13.5 | 14.0 | 17.8 | 15.1 |
Less than every week | 56.9 | 60.9 | 61.0 | 59.7 |
Every week | 29.5 | 25.0 | 20.1 | 24.7 |
Missing | 0.1 | 0.1 | 1.2 | 0.5 |
Menarche < 12 years | 14.4 | 12.7 | 11.0 | 12.6 |
Missing | 0.1 | 0.7 | 1.4 | 0.7 |
OC-use | 4.5 | 7.1 | 11.1 | 7.6 |
Missing | - | 0.1 | 0.9 | 0.4 |
Nulliparity | 17.4 | 15.4 | 18.6 | 17.1 |
Missing | - | 0.1 | 0.7 | 0.3 |
Peri/postmenopausal | 41.2 | 63.3 | 75.5 | 60.5 |
HRT in peri/postmenopausal | 13.9 | 13.8 | 17.6 | 15.4 |
Missing | - | - | 0.2 | 0.1 |
Height | ||||
≤160 | 24.6 | 30.6 | 33.3 | 29.7 |
>160 ≤ 165 | 32.7 | 32.3 | 31.0 | 32.0 |
>165 ≤ 170 | 27.0 | 22.9 | 24.3 | 24.6 |
>170 | 15.7 | 14.2 | 11.4 | 13.7 |
BMI | ||||
<20 | 13.8 | 8.5 | 8.3 | 10.1 |
≥20 < 25 | 62.2 | 55.0 | 47.6 | 54.7 |
≥25 < 30 | 18.3 | 27.7 | 29.8 | 25.5 |
≥30 | 5.7 | 8.8 | 14.4 | 9.7 |