Table 4.

ORs of breast cancer associated with GST genotypes (GSTM1 and GSTT1) stratified by reproductive factors (A: parity; B: age at menarche; C: menopausal status)

Cases/controlsOR* (95% CI)Cases/controlsOR* (95% CI)Cases/controlsOR* (95% CI)Interaction P
ATotalNulliparous WomenParous Women
GSTM1+107/1061.021/221.086/841.0
GSTM1109/1330.80 (0.55–1.16)17/230.78 (0.33–1.88)92/1100.81 (0.54–1.22)0.95
GSTT1+165/1891.027/341.0138/1551.0
GSTT151/501.17 (0.75–1.82)11/111.14 (0.42–3.09)40/391.16 (0.70–1.91)0.93
BTotalMenarche ≤13 yMenarche >13 y
GSTM1+189/2121.0130/1521.059/601.0
GSTM1189/2330.89 (0.68–1.18)142/1670.97 (0.70 –1.35)47/660.73 (0.43–1.23)0.34
GSTT1+79/841.056/631.023/211.0
GSTT123/250.96 (0.50–1.84)15/190.94 (0.43–2.03)8/61.00 (0.28–3.59)0.93
CTotalPremenopausal WomenPostmenopausal Women
GSTM1+320/4821.061/571.0259/4251.0
GSTM1318/5210.92 (0.75–1.12)55/670.77 (0.46–1.28)263/4540.95 (0.76–1.18)0.45
GSTT1+235/4101.023/321.0212/3781.0
GSTT182/1081.31 (0.94–1.83)6/90.93 (0.29–2.97)76/991.35 (0.96–1.91)0.54
  • * ORs were adjusted for study center.

  • The total number of cases and controls in these columns refers to subjects with available information on the stratifying variable.

  • Reference category.