Table 3.

Multivariable global hazard of having a second breast cancer event diagnosed adjusted for all variables in the table

	Model 4a (N = 8,662)
	HR	95% CI	P value
Breast density (before 1st diagnosis and within 2 years of mammogram used for mode of detection)
Almost entirely fatty	Ref		0.6859
Scattered fibroglandular	1.07	(0.60, 1.90)
Heterogeneously dense	1.20	(0.67, 2.13)
Extremely dense	1.30	(0.68, 2.48)
Mode of 1st cancer diagnosis
Screen-detected	Ref		0.0008
Screen interval-detected	1.38	(1.02, 1.86)
Diagnostic detected	1.78	(1.35, 2.35)
Diagnostic interval-detected	1.32	(0.86, 2.04)
1st degree family history of breast cancer (before 1st diagnosis)
No	Ref		0.9442
Yes	1.01	(0.77, 1.32)
Age at 1st diagnosis
18–39	1.06	(0.61–1.83)	0.6809
40–49	0.99	(0.72–1.35)
50–59	Ref
60–69	1.08	(0.79–1.49)
70–79	1.17	(0.84–1.65)
80+	0.76	(0.44–1.30)
Stage at 1st diagnosis
0	1.66	(1.25–2.21)	0.003
I	Ref
IIA	0.91	(0.66–1.26)
IIB	1.12	(0.75–1.66)
Adjuvant therapy
Neither	Ref		0.0067
Chemotherapy	1.22	(0.86–1.75)
Hormonal	0.68	(0.51–0.93)
Both	0.75	(0.47–1.18)

P values are based on likelihood ratio tests and are also adjusted for mammography registry

^aP ≤ 0.05