From: Mammographic density and breast cancer risk: a mediation analysis
Selected risk factor | OR (95 % CI) not adjusted for MD | OR (95 % CI) adjusted for MD | Percent mediated by MD (p value) |
---|---|---|---|
Childhood somatotypea Per 1-unit increase | |||
 Percent MDc | 0.89 (0.83,0.96) | 0.92 (0.85,0.99) | 26 % (p = 0.01) |
 Dense areac | 0.89 (0.83,0.96) | 0.91 (0.84,0.98) | 16 % (p = 0.02) |
 Non-dense areac | 0.89 (0.83,0.96) | 0.90 (0.84,0.97) | 10 % (p = 0.10) |
Adolescent somatotypea Per 1-unit increase | |||
 Percent MDc | 0.86 (0.80,0.93) | 0.90 (0.83,0.97) | 26 % (p = 0.01) |
 Dense areac | 0.86 (0.80,0.93) | 0.88 (0.81,0.95) | 13 % (p = 0.01) |
 Non-dense areac | 0.86 (0.80,0.93) | 0.88 (0.81,0.95) | 10 % (p = 0.13) |
BMI at age 18 (kg/m2)a Per 5-unit increase | |||
 Percent MDc | 0.88 (0.74,1.05) | 1.00 (0.83,1.19) | 98 % (p = 0.17) |
 Dense areac | 0.88 (0.74,1.05) | 0.92 (0.77,1.10) | 35 % (p = 0.19) |
 Non-dense areac | 0.88 (0.74,1.05) | 0.94 (0.78,1.13) | 51 % (p = 0.24) |
Weight change since 18b Per 20-lb increase | |||
 Percent MDc | 1.03 (0.96,1.10) | 1.11 (1.03,1.19) | Not mediatedd |
 Dense areac | 1.03 (0.96,1.10) | 1.04 (0.97,1.12) | Not mediatedd |
 Non-dense areac | 1.03 (0.96,1.10) | 1.10 (1.01,1.19) | Not mediatedd |
BMI (kg/m2) Per 5-unit increase | |||
 Percent MDc | 1.05 (0.95,1.16) | 1.17 (1.05,1.30) | Not mediatedd |
 Dense areac | 1.05 (0.95,1.16) | 1.07 (0.96,1.18) | Not mediatedd |
 Non-dense areac | 1.05 (0.95,1.16) | 1.16 (1.02,1.30) | Not mediatedd |
Height Per 3-inch increase | |||
 Percent MDc | 0.95 (0.85,1.06) | 0.96 (0.86,1.07) | 22 % (p = 0.41) |
 Dense areac | 0.95 (0.85,1.06) | 0.95 (0.85,1.06) | Not mediatedd |
 Non-dense areac | 0.95 (0.85,1.06) | 0.96 (0.86,1.07) | 20 % (p = 0.39) |
Age at menarche Per 2-year increase | |||
 Percent MDc | 0.92 (0.80,1.05) | 0.93 (0.81,1.06) | 11 % (p = 0.37) |
 Dense areac | 0.92 (0.80,1.05) | 0.93 (0.81,1.06) | 13 % (p = 0.31) |
 Non-dense areac | 0.92 (0.80,1.05) | 0.92 (0.80,1.05) | Not mediatedd |
Nulliparous Nulliparous vs parous | |||
 Percent MDc | 1.22 (0.88,1.69) | 1.12 (0.80,1.56) | 43 % (p = 0.26) |
 Dense areac | 1.22 (0.88,1.69) | 1.14 (0.82,1.59) | 32 % (p = 0.28) |
 Non-dense areac | 1.22 (0.88,1.69) | 1.19 (0.86,1.65) | 11 % (p = 0.36) |
Birth index Per 102-unit increase | |||
 Percent MDc | 0.96 (0.73,1.25) | 1.04 (0.79,1.36) | Not mediatede |
 Dense areac | 0.96 (0.73,1.25) | 1.01 (0.78,1.33) | Not mediatede |
 Non-dense areac | 0.96 (0.73,1.25) | 0.97 (0.74,1.27) | 38 % (p = 0.75) |
Parity (among parous) Per one-child increase | |||
 Percent MDc | 1.02 (0.95,1.09) | 1.03 (0.96,1.11) | Not mediatedd |
 Dense areac | 1.02 (0.95,1.09) | 1.03 (0.96,1.10) | Not mediatedd |
 Non-dense areac | 1.02 (0.95,1.09) | 1.02 (0.95,1.09) | Not mediatedd |
Age at first birth (among parous) Per 5-year increase | |||
 Percent MDc | 1.23 (1.07,1.41) | 1.19 (1.04,1.38) | 13 % (p = 0.05) |
 Dense areac | 1.23 (1.07,1.41) | 1.20 (1.05,1.39) | 9 % (p = 0.09) |
 Non-dense areac | 1.23 (1.07,1.41) | 1.21 (1.05,1.40) | 5 % (p = 0.15) |
Breastfeeding (among parous) Ever vs never | |||
 Percent MDc | 0.96 (0.79,1.16) | 0.97 (0.80,1.17) | 22 % (p = 0.70) |
 Dense areac | 0.96 (0.79,1.16) | 0.96 (0.79,1.17) | 11 % (p = 0.74) |
 Non-dense areac | 0.96 (0.79,1.16) | 0.97 (0.80,1.17) | 19 % (p = 0.68) |
Breastfeeding (among parous women who ever breastfed) Per 12-month increase | |||
 Percent MDc | 1.25 (1.06,1.46) | 1.25 (1.06,1.47) | Not mediatedd |
 Dense areac | 1.25 (1.06,1.46) | 1.24 (1.06,1.46) | 2 % (p = 0.57) |
 Non-dense areac | 1.25 (1.06,1.46) | 1.26 (1.07,1.48) | Not mediatedd |
Alcohol use Per 10Â g/day increase | |||
 Percent MDc | 1.01 (0.90,1.14) | 1.00 (0.89,1.13) | 73 % (p = 0.85) |
 Dense areac | 1.01 (0.90,1.14) | 1.01 (0.90,1.13) | 41 % (p = 0.85) |
 Non-dense areac | 1.01 (0.90,1.14) | 1.01 (0.90,1.13) | 38 % (p = 0.85) |
Family history of breast cancer Yes vs no | |||
 Percent MDc | 1.45 (1.15,1.85) | 1.45 (1.14,1.84) | 1 % (p = 0.78) |
 Dense areac | 1.45 (1.15,1.85) | 1.44 (1.14,1.84) | 2 % (p = 0.52) |
 Non-dense areac | 1.45 (1.15,1.85) | 1.46 (1.15,1.86) | Not mediatedd |
History of biopsy-confirmed BBD Yes vs no | |||
 Percent MDc | 1.29 (1.04,1.61) | 1.19 (0.95,1.48) | 33 % (p = 0.04) |
 Dense areac | 1.29 (1.04,1.61) | 1.22 (0.98,1.52) | 24 % (p = 0.05) |
 Non-dense areac | 1.29 (1.04,1.61) | 1.27 (1.02,1.58) | 8 % (p = 0.12) |
History of unconfirmed BBD Yes vs no | |||
 Percent MDc | 1.19 (0.95,1.48) | 1.13 (0.90,1.41) | 29 % (p = 0.17) |
 Dense areac | 1.19 (0.95,1.48) | 1.13 (0.91,1.41) | 28 % (p = 0.17) |
 Non-dense areac | 1.19 (0.95,1.48) | 1.19 (0.95,1.48) | 0 % (p = 0.97) |
Age at menopause Per 4-year increase | |||
 Percent MDc | 1.12 (1.05,1.20) | 1.12 (1.04,1.19) | 5 % (p = 0.22) |
 Dense areac | 1.12 (1.05,1.20) | 1.12 (1.05,1.20) | 3 % (p = 0.30) |
 Non-dense areac | 1.12 (1.05,1.20) | 1.12 (1.05,1.20) | 3 % (p = 0.20) |
Hormone therapy use Past vs never | |||
 Percent MDc | 1.18 (0.91,1.53) | 1.12 (0.86,1.46) | 31 % (p = 0.26) |
 Dense areac | 1.18 (0.91,1.53) | 1.15 (0.88,1.50) | 14 % (p = 0.31) |
 Non-dense areac | 1.18 (0.91,1.53) | 1.15 (0.88,1.50) | 13 % (p = 0.31) |
Hormone therapy use Current vs never | |||
 Percent MDc | 1.71 (1.37,2.13) | 1.52 (1.22,1.90) | 22 % (p < 0.01) |
 Dense areac | 1.71 (1.37,2.13) | 1.58 (1.27,1.98) | 14 % (p < 0.01) |
 Non-dense areac | 1.71 (1.37,2.13) | 1.65 (1.32,2.05) | 7 % (p = 0.02) |