Table 3.

ORs for incidence of breast cancer in relation to quartiles of mammographic density (%) among women not currently using menopausal hormone replacement therapy.

Mammographic density, quartilesa
1st2nd3rd4th
N cases/controlsOR (95% CI)OR (95% CI)OR (95% CI)OR (95% CI)P value trendb
Premenopausal women
Mammographic density
Model 1194/3551.01.11 (0.62–2.00)1.59 (0.89–2.91)2.55 (1.39–4.68)<0.001
Model 2146/2751.01.20 (0.62–2.31)1.53 (0.76–3.07)2.13 (1.08–4.23)0.006
Model 3181/3281.01.27 (0.69–2.34)1.84 (0.97–3.49)2.69 (1.41–5.14)<0.001
Postmenopausal women
Mammographic density
Model 1379/7871.01.64 (1.11–2.41)2.17 (1.45–3.24)2.55 (1.66–3.92)<0.001
Model 2367/5641.01.93 (1.21–3.09)2.29 (1.39–3.75)2.40 (1.42–4.06)0.001
Model 3356/7351.01.60 (1.07–2.38)2.15 (1.42–3.26)2.46 (1.58–3.85)0.009
  • Note: Model 1: Adjusted for age and BMI at blood draw (continuous), history of benign breast disorder (no, yes), family history of breast cancer (no, yes), smoking status (never, past, current smoker), alcohol consumption (g/d), time of day of blood draw, and menopausal hormone therapy (never, previous use; postmenopausal women only). Model 2: as Model 1, with addition of DHEA (log-transformed, continuous). Model 3: as Model 1, with addition of DHEAS (log-transformed, continuous).

  • aMammographic density (%), premenopausal: 1st: <13.6, 2nd: 13.6–30.3, 3rd: 30.3–43.3, 4th: ≥43.4, postmenopausal: 1st: <2.9, 2nd: 2.9–9.1, 3rd: 9.1–20.6, 4th: ≥20.7.

  • bP value based on Wald test of square root–transformed mammographic density (%), treated as a continuous variable.