Table 3.

Mendelian randomization estimates between circulating concentrations of insulin-like growth factor-1 (IGF-1) and insulin-like growth factor-binding protein-3 (IGFBP-3) and risk of breast cancer (N = 122 977 breast cancer cases and N = 105 974 controls)

	Mendelian randomization (MR)
	Inverse-variance-weighted (IVW)	Weighted median	MR-Egger
	OR (95% CI) per 5 nmol/l increment	OR (95% CI) per 5 nmol/l increment	OR (95% CI) per 5 nmol/l increment
IGF-1 (n = 265 SNPs)
Breast cancer	1.05 (1.01–1.10)	1.08 (1.03–1.13)	1.12 (1.01–1.25)
Breast cancer, ER+	1.06 (1.01–1.11)	1.10 (1.04–1.18)	1.12 (1.00–1.26)
Breast cancer, ER−	1.02 (0.96–1.08)	1.03 (0.95–1.11)	1.17 (1.02–1.34)

	IVW	Weighted median	MR-Egger
	OR (95% CI) per 1-SD increment	OR (95% CI) per 1-SD increment	OR (95% CI) per 1-SD increment
IGFBP-3 (n = 4 SNPs)
Breast cancer	1.00 (0.97–1.04)	1.00 (0.96–1.04)	0.95 (0.87–1.03)
Breast cancer, ER+	1.00 (0.96–1.05)	1.00 (0.95–1.04)	0.92 (0.83–1.02)
Breast cancer, ER−	0.98 (0.92–1.04)	0.98 (0.91–1.05)	1.03 (0.88–1.20)

CI, confidence interval; ER, estrogen receptor; OR, odds ratio; SD, standard deviation; SNP, single nucleotide polymorphism.