Skip to main content

Table 2 Baseline characteristics of study population matched by age, date of mammogram, and study

From: Mammographic texture and risk of breast cancer by tumor type and estrogen receptor status

  Cases Controls
N 1171 1659
Mean age at mammogram (years) 55.4 (10.6) 55.3 (10.6)
Mean age at diagnosis (years) 60.5 (10.8)
Mean BMI (kg/m2) 25.7 (6.1) 25.8 (6.8)
Body mass index categories (kg/m2)*
  < 25 551 (47.1%) 854 (51.5%)
 25–29 369 (31.5%) 443 (26.7%)
 30–34 155 (13.2%) 196 (11.8%)
 35+ 73 (6.2%) 136 (8.2%)
 Unknown 23 (2.0%) 30 (1.8%)
Menopausal Status
 Premenopausal 430 (36.7%) 632 (38.1%)
 Postmenopausal 697 (59.5%) 962 (58%)
 Unknown 44 (3.8%) 65 (3.9%)
Parity
 Nulliparous 169 (14.4%) 218 (13.1%)
 Parous 977 (83.4%) 1415 (85.3%)
 Unknown 25 (2.1%) 26 (1.6%)
Postmenopausal hormone therapya*   
 Not current 255 (51.5%) 367 (57.5%)
 Current, estrogen 116 (23.4%) 156 (24.5%)
 Current, estrogen + progestin 124 (25.1%) 115 (18.0%)
Family history*
 No 973 (83.1%) 1453 (87.6%)
 Yes 196 (16.7%) 206 (12.4%)
 Unknown 2 (0.2%) 0 (0%)
Standardized mean percent mammographic density (%)* 32.9 (18.7) 27.9 (18.4)
Standardized mean dense area (cm2)* 63.5 (43.1) 52.2 (37.8)
Standardized mean non-dense area (cm2)* 149.4 (98.7) 158.9 (102.1)
  1. Data are presented as the mean (standard deviation) or number (%).
  2. aAmong postmenopausal women in MMHS, NHS, NHSII, and SFMR
  3. *p < 0.05, cases versus controls
  4. BMI body mass index