Table 4.

BMI and T2D in relation to ER+ and ER− breast cancer incidence, stratified by menopausal status

ER+ breast cancerER− breast cancer
CasesMV HR (95% CI)CasesMV HR (95% CI)
Premenopausal
T2D
 No300Reference176Reference
 Yes121.15 (0.64–2.08)122.39 (1.30–4.39)
BMI (kg/m2)
 <2592Reference53Reference
 25–291031.00 (0.75–1.34)661.12 (0.77–1.62)
 30–34580.96 (0.68–1.36)411.13 (0.73–1.76)
 ≥35591.20 (0.82–1.76)270.81 (0.47–1.40)
Postmenopausal
T2D
 No441Reference188Reference
 Yes560.99 (0.74–1.32)261.27 (0.83–1.95)
BMI (kg/m2)
 <2589Reference48Reference
 25–291761.22 (0.95–1.59)901.07 (0.75–1.53)
 30–341411.53 (1.16–2.02)460.82 (0.54–1.24)
 ≥35971.53 (1.12–2.09)350.83 (0.52–1.34)
  • NOTE: HRs adjusted for age, BMI at age 18, parity, age at first birth, age at menarche, duration of oral contraceptive use, duration of menopausal hormone use, first degree family history of breast cancer, and BMI for the T2D analysis or T2D for the BMI analysis. Pinteraction of T2D and menopausal status: 0.95 for ER+ and 0.13 for ER− cancer. Pinteraction of BMI and menopausal status: 0.02 for ER+ and 0.52 for ER− cancer.