Table 4.
Association between +331G/A PR polymorphism and risk of postmenopausal breast cancer by duration of PMH used
| PMH use status | GG | AG+AA | 2P - int | ||||
|---|---|---|---|---|---|---|---|
| Cases, n (%) | Controls, n (%) | OR (95%CI)1 | Cases, n (%) | Controls, n (%) | OR (95%CI) | ||
| Never | 258 (83%) | 607 (92%) | 1.00 (ref) | 53 (17%) | 50 (8%) | 2.57 (1.64-4.02) | |
| Past | |||||||
| < 5 years | 178 (87%) | 370 (91%) | 1.00 (ref) | 26 (13%) | 37 (9%) | 1.62 (0.89-2.94) | |
| ≥ 5 years | 158 (92%) | 204 (92%) | 1.00 (ref) | 13 (8%) | 17 (8%) | 0.93 (0.41-2.11) | |
| Current | |||||||
| < 5 years | 174 (89%) | 209 (92%) | 1.00 (ref) | 21 (11%) | 18 (8%) | 1.60 (0.79-3.24) | |
| ≥ 5 years | 630 (89%) | 682 (90%) | 1.00 (ref) | 76 (11%) | 79 (10%) | 1.06 (0.75-1.51) | |
| 0.04 | |||||||
1
Unconditional logistic regression adjusted for age, date blood draw, age at menarche, age at menopause, age at first birth/parity, BMI at age 18, weight gain since age 18, history of benign breast disease, first-degree family history of breast cancer, and alcohol consumption.
2
P - int = P for interaction based on likelihood ratio test comparing unconditional logistic regression models with and without interaction terms between PMH use status (past or current, <5 or ≥5 years) and genotype (GG, AG+GG)(degrees of freedom = 4).