Table 6.

Abdominal adiposity and breast cancer risk in postmenopausal women not currently using hormone therapy by current BMI

	Current BMI < 25.0kg/m2			Current BMI ≥ 25.0kg/m2
All breast cancer	Cases (n=396)	Controls (n=648)	OR a 95% CI	Cases (n=402)	Controls (n=680)	OR a 95% CI	P interaction
Waist (cm) b
M1: ≤ 90.5	151	272	1.00	140	321	0.87 0.65-1.18	0.25
M2: > 90.5	27	26	1.90 1.05-3.44	387	585	1.21 0.93-1.57
Waist-to-height ratio b
M1: ≤ 0.58	156	276	1.00	152	310	0.93 0.69-1.24	0.93
M2: > 0.58	22	22	1.87 0.98-3.56	375	596	1.17 0.90-1.52
ER+PR+ breast cancer	Cases (n=194)	Controls (n=648)	OR a 95% CI	Cases (n=220)	Controls (n=680)	OR a 95% CI	P interaction
Waist (cm) b
M1: ≤ 90.5	73	272	1.00	67	321	0.92 0.62-1.36	0.16
M2: > 90.5	10	26	1.53 0.69-3.39	213	585	1.55 1.11-2.17
Waist-to-height ratio b
M1: ≤ 0.58	75	276	1.00	75	310	1.02 0.70-1.50	0.47
M2: > 0.58	8	22	1.53 0.63-3.68	205	596	1.52 1.08-2.12

Abbreviations: BMI, body mass index; CI, confidence interval; ER+, estrogen receptor–positive; OR, odds ratio; PR+, progesterone receptor–positive.

^a OR and 95% CI adjusted for age (years, continuous), race/ethnicity (non-Hispanic White, African American, Hispanic), place of birth (US-born, foreign-born), education (some high school or less, high school or vocational/technical school graduate, some college, college graduate), family history of breast cancer in first-degree relatives (no, yes), personal history of biopsy-confirmed benign breast disease (no, yes), age at menarche (≤11, 12, 13, ≥14 years), number of full-term pregnancies (nulliparous, 1, 2, 3, ≥4), age at first full-term pregnancy (nulliparous, ≤19, 20–24, 25–29, ≥30 years), lifetime breast-feeding (nulliparous, 0, ≤6, 7–12, 13–24, ≥25 months), lifetime physical activity (quartiles, hours/week), alcohol consumption in reference year (0, 0.1-4.9, 5–9.9, 10–19.9, ≥20 g/day), and total caloric intake (quartiles, kcal/day).

^b Based on median among all postmenopausal controls.