Table 1.
Study characteristics of the breast cancer case-control study in Germany and variable definition.
| Variable | Definition | Levels | Cases | Controls |
|---|---|---|---|---|
| 654 | 1085 | |||
| Age | 42.5 +/- 5.7 | 42.6 +/- 5.7 | ||
| Family history | first-degree relatives with breast cancer | none | 87.80% | 94.80% |
| at least 1 | 12.20% | 5.20% | ||
| Menopausal statusa | premenopausal | 78.70% | 80.60% | |
| postmenopausal | 6.30% | 6.50% | ||
| unknown | 15.00% | 12.90% | ||
| Smoking | packyears over a lifetime | 8.27 +/- 12.20 | 6.96 +/- 10.88 | |
| NAT1 | number *10 alleles | 0 | 64.10% | 68.60% |
| 1 | 32.30% | 28.60% | ||
| 2 | 3.70% | 2.90% | ||
| CYP1B1 | number *3 alleles | 0 | 31.00% | 28.90% |
| 1 | 51.70% | 50.90% | ||
| 2 | 17.30% | 20.20% | ||
| NAT2 | presence of at least one *4 allele | fast acetylator | 43.70% | 39.80% |
| slow acetylator | 56.30% | 60.20% | ||
| CYP1A1 | homozygote for *1 allele | Yes | 75.80% | 75.10% |
| No | 24.20% | 24.90% | ||
| GSTT1 | absence of gene product | No | 84.30% | 81.90% |
| Yes | 15.70% | 18.10% | ||
| GSTM1 | absence of gene product | No | 45.70% | 48.80% |
| Yes | 54.30% | 51.20% |
a Women with a hysterectomy not accompanied by bilateral oophorectomy were classified as unknown