Table 4.

Risk of breast cancer by ER/PR status and glycemic index score in adolescence and early adulthood diet among all women in the Nurses’ Health Study II

		Quintile of intake
	No. of cases	1	2	3	4	5
Adolescence
Estrogen and progesterone receptor positive	695	1	1.24 (0.99–1.55)	0.88 (0.69–1.13)	0.98 (0.77–1.25)	1.21 (0.95–1.53)
Estrogen and progesterone receptor negative	162	1	1.39 (0.88–2.20)	1.01 (0.62–1.66)	0.93 (0.56–1.55)	0.93 (0.56–1.56)
P-value, test for interaction			0.65	0.63	0.86	0.36
Early adulthood
Estrogen and progesterone receptor positive	1571	1	1.02 (0.87–1.19)	1.02 (0.88–1.20)	1.03 (0.88–1.21)	1.05 (0.90–1.24)
Estrogen and progesterone receptor negative	433	1	1.15 (0.86–1.54)	1.03 (0.76–1.40)	1.13 (0.84–1.52)	0.96 (0.70–1.31)
P-value, test for interaction			0.46	0.96	0.59	0.59

^*Multivariable model was stratified by age in months at start of follow-up and calendar year of the current questionnaire cycle and was simultaneously adjusted for race (white, non-white), family history of breast cancer in mother or sisters (yes, no), history of benign breast disease (yes, no), smoking (never, past, current 1 to 14/day, current 15 to 24/day, current ≥25/day), height (<62, 62 to <65, 65 to <68, ≥68 inches), BMI at age 18 years (<18.5, 18.5 to <20.0, 20.0 to <22.5, 22.5 to <25.0, 25.0 to <30.0, ≥30.0 kg/m2), weight gain since age 18 (≤−5, >−5–5, >5–10, >10–20, >20 kg), age at menarche (<12, 12, 13, ≥14 years), parity and age at first birth (nulliparous, parity ≤2 and age at first birth <25 years, parity≤2 and age at first birth 25 to <30 years, parity ≤2 and age at first birth ≥30 years, parity 3 to 4 and age at first birth <25 years, parity 3 to 4 and age at first birth 25 to <30 years, parity 3 to 4 and age at first birth ≥30 years, parity ≥5 and age at first birth <25 years, parity ≥5 and age at first birth ≥25 years), oral contraceptive use (never, past, current), alcohol intake (nondrinker, <5, 5 to <15, ≥15 g/day), and energy (quintile). In postmenopausal women, we additionally adjusted for hormone use (postmenopausal never users, postmenopausal past users, postmenopausal current users), age at menopause (<45 years, 45 to 46 years, 47 to 48, 49 to 50 years, 51 to 52 years, ≥53 years). Among all women, we additionally adjusted for hormone use and menopausal status (premenopausal, postmenopausal never users, postmenopausal past users, postmenopausal current users, unknown menopausal status) and, age at menopause (premenopausal, unknown menopause, <45 years, 45 to 46 years, 47 to 48, 49 to 50 years, 51 to 52 years, ≥53 years). For adolescent GI, we additionally adjusted for adolescent alcohol intake (nondrinker, <1.5, 1.5–<5, 5–<10, ≥10 g/day) and adolescent energy intake (instead of adult energy intake).