Table 3.

Association of dietary cadmium intake with breast cancer stratified by smoking, breast cancer risk factors, total intake of zinc, calcium, and iron, and tumor estrogen receptor expression.

	N	Cases	aHRa,b	(95% CI)b	Pinteraction
Cigarette smoking
Never	14,787	491	1.01	(0.98–1.04)
Ever	12,014	408	0.99	(0.96–1.01)	0.07
HRT usec
Never	16,121	487	0.99	(0.97–1.02)
Ever	10,680	412	1.00	(0.98–1.03)	0.44
BMI (kg/m2)
<25	10,903	345	1.01	(0.98–1.03)
≥25	15,898	554	0.99	(0.97–1.02)	0.27
Parity
Nulliparous	3,341	128	1.00	(0.97–1.04)
Parous	23,460	771	1.00	(0.97–1.02)	0.71
Vegetable consumption (servings/d)d
<3	20,217	668	1.02	(0.97–1.04)
≥3	6,584	231	1.00	(0.97–1.02)	0.65
Regular multivitamin use
Ever	7,586	272	1.00	(0.97–1.04)
Never	19,215	627	1.00	(0.97–1.02)	0.82
Zinc (mg/d)e
<10.3	6,484	225	1.02	(0.98–1.07)
≥10.3	20,317	674	1.00	(0.97–1.02)	0.18
Iron (mg/d)e
<11.7	6,343	224	1.00	(0.94–1.05)
≥11.7	20,458	675	1.00	(0.98–1.02)	0.91
Calcium (mg/d)e
<706.7	6,516	212	1.00	(0.95–1.04)
≥706.7	20,285	687	1.00	(0.98–1.02)	0.95
Tumor estrogen receptor status					P-differencef
ER+	26,801	757	1.00	(0.98–1.03)
ER−	26,801	123	0.94	(0.89–1.01)	0.11

^aAdjusted for age, total energy intake, education, race, HRT use (combined estrogen and progesterone), vegetable consumption (excluding potatoes), potato consumption, whole grain consumption, cigarette smoking, BMI, physical activity, alcohol consumption, age at first childbirth, multivitamin use, and mammography.

^bper μg cadmium/day.

^cHormone replacement therapy, combined estrogen and progesterone preparations.

^dExcluding potatoes; cut-off corresponds approximately to lowest quartile among all participants.

^eTotal intake from diet and multivitamins; cut-offs correspond to lowest quartile among all participants.

^fP-value for difference between ER+ and ER− in association with dietary cadmium, from nested case-control analysis.