Characteristics | Interviewed participants not included in the current analysis (n = 720) | Interviewed participants included in the current analysis (non-Hispanic white EPT quitters) (n = 284) | P values |
---|---|---|---|
At cohort enrollment | Â | Â | Â |
Age (mean ± SD) | 49.9 ± 4.2 (range 40-60) | 50.5 ± 3.8 (range 41-60) | 0.07 |
BMI (kg/m2) | 24.6 ± 4.8 (range 17-50) | 24.7 ± 4.9 (range 17-47) | 0.68 |
White (N (%)) | 624 (87%) | 284 (100%) | Â |
Nulliparous women (N (%)) | 141 (20%) | 63 (22%) | 0.33 |
Menopausal status | Â | Â | Â |
 Premenopausal | 432 (60%) | 155 (55%) | 0.012 |
 Perimenopausal | 87 (12%) | 55 (19%) |  |
 Postmenopausal | 201 (28%) | 74 (26%) |  |
Ever had breast biopsy (N (%)) | 108 (15%) | 40 (14%) | 0.71 |
Positive 1st degree family history of breast cancer (N (%)) | 64 (9%) | 37 (13%) | 0.053 |
At mammogram substudy enrollment | Â | Â | Â |
Age at interview (mean ± SD) | 62 ± 4.0 (range 52-71) | 62 ± 3.6 (range 53-72) | 0.11 |
BMI (kg/m2) | 26.2 ± 5.2 (range 17-49) | 25.7 ± 5.0 (range 18-47) | 0.16 |
Positive 1st degree family history of breast cancer (N (%)) | 112 (16%) | 51 (18%) | 0.43 |
Number of mammograms in the past 10 years | 8.8 ± 2.3 (range 2-20) | 8.9 ± 2.2 (range 2-18) | 0.59 |
At time of mammography evaluated for density | Â | Â | Â |
Age at time of mammogram while taking EPT |  | 56 ± 4 (range 45-67) |  |
Age at time of mammogram while off EPT |  | 60 ± 5 (range 49-71) |  |
BMI at time of mammogram while taking EPT |  | 25.7 ± 5.2 (range 18-47) |  |
BMI at time of mammogram while off EPT |  | 25.8 ± 5.0 (range 18-48) |  |
Years on EPT at time of mammogram while taking EPT | Â | Â | Â |
 <1 year |  | 15 (5%) |  |
 1- < 4 years |  | 121 (43%) |  |
 4- < 7 years |  | 112 (39%) |  |
 ≥7 years |  | 36 (13%) |  |
Time interval between two mammograms (years) | Â | Â | Â |
 ≤3 years |  | 141 (50%) |  |
 4-5 years |  | 106 (37%) |  |
 6-9 years |  | 37 (13%) |  |