Table 3.
Association of fibroids or endometriosis with breast cancer, stratified by menopause-time
| Person-Years | Breast Cancer Events | Age Adjusted HR (95% CI) | Partially Adjusted HR (95% CI) | Fully Adjusted HR (95% CI) | |
|---|---|---|---|---|---|
| Pre-Menopausal Person-Time | |||||
| Fibroids | |||||
| No Fibroids | 11,309 | 890 | Ref | Ref | Ref |
| Fibroids | 5,242 | 464 | 1.07 (0.96 to 1.20) | 1.07 (0.95 to 1.20) | 1.09 (0.97 to 1.23) |
| Fibroids +/− Surgery | |||||
| No Fibroids | 11,309 | 890 | Ref | Ref | Ref |
| Fibroids Without Hysterectomy | 3,328 | 297 | 1.09 (0.95 to 1.24) | 1.08 (0.95 to 1.24) | 1.09 (0.95 to 1.24) |
| Fibroids With Hysterectomy | 1,914 | 167 | 1.04 (0.88 to 1.23) | 1.04 (0.87 to 1.23) | 1.07 (0.90 to 1.28) |
| Endometriosis | |||||
| No Endometriosis | 14,469 | 1,170 | Ref | Ref | Ref |
| Endometriosis | 2,082 | 184 | 1.08 (0.92 to 1.26) | 1.07 (0.91 to 1.25) | 1.09 (0.93 to 1.28) |
| Endometriosis +/− Surgery | |||||
| No Endometriosis | 14,469 | 1,170 | Ref | Ref | Ref |
| Endometriosis Without Hysterectomy | 1,238 | 110 | 1.10 (0.91 to 1.34) | 1.09 (0.90 to 1.33) | 1.09 (0.89 to 1.32) |
| Endometriosis With Hysterectomy | 845 | 74 | 1.04 (0.83 to 1.32) | 1.03 (0.82 to 1.31) | 1.08 (0.85 to 1.37) |
| Post-Menopausal Person-Time | |||||
| Fibroids | |||||
| No Fibroids | 19,753 | 1,840 | Ref | Ref | Ref |
| Fibroids | 12,196 | 1,225 | 1.08 (1.00 to 1.16) | 1.06 (0.98 to 1.14) | 1.09 (1.01 to 1.18) |
| Fibroids +/− Surgery | |||||
| No Fibroids | 19,753 | 1,840 | Ref | Ref | Ref |
| Fibroids Without Surgery | 4,597 | 464 | 1.10 (0.99 to 1.21) | 1.07 (0.97 to 1.19) | 1.07 (0.96 to 1.18) |
| Fibroids With Hysterectomy Only | 2,246 | 273 | 1.22 (1.07 to 1.38) | 1.19 (1.05 to 1.36) | 1.24 (1.08 to 1.41) |
| Fibroids With Bilateral Oophorectomy | 5,352 | 488 | 1.00 (0.91 to 1.11) | 0.98 (0.88 to 1.08) | 0.99 (0.89 to 1.10) |
| Endometriosis | |||||
| No Endometriosis | 26,536 | 2,580 | Ref | Ref | Ref |
| Endometriosis | 5,413 | 485 | 0.97 (0.88 to 1.06) | 0.95 (0.86 to 1.05) | 0.98 (0.88 to 1.09) |
| Endometriosis +/− Surgery | |||||
| No Endometriosis | 26,536 | 2,580 | Ref | Ref | Ref |
| Endometriosis Without Surgery | 1,430 | 142 | 1.07 (0.91 to 1.27) | 1.05 (0.89 to 1.25) | 1.04 (0.88 to 1.23) |
| Endometriosis With Hysterectomy Only | 843 | 92 | 1.06 (0.86 to 1.31) | 1.05 (0.86 to 1.30) | 1.08 (0.87 to 1.33) |
| Endometriosis With Bilateral Oophorectomy | 3,140 | 251 | 0.88 (0.78 to 1.01) | 0.87 (0.76 to 0.99) | 0.87 (0.76 to 1.00) |
| Heterogeneity testing with Wald test (p-value) for association between fibroids or endometriosis and breast cancer by menopausal status | |||||
| Fibroids | 0.91 | 0.83 | 0.51 | ||
| Endometriosis | 0.23 | 0.23 | 0.38 | ||