Table 5.

Association of change^a in %MD between prior to/at first diagnosis^b and post diagnosis^c with CBC risk

Difference in %MD	CBCd Number (%)	UBCd Number (%)	ORe (95% CI)
Difference <10%	150 (71)	144 (64)	1.00
Decrease ≥10%	60 (29)	81 (36)	0.63 (0.40, 1.01)

Abbreviations: %MD percent mammographic density, CBC contralateral breast cancer, UBC unilateral breast cancer, OR odds ratio, CI confidence interval

^aDefined as the difference between the two time points

^bPrior to/at 1st diagnosis was 36 months prior up to 1 month post diagnosis

^cPost diagnosis was > 6 months up to 48 months post diagnosis

^dExcluding those with missing menopausal status information and those with an increase ≥10%

^eOR adjusted for change in age, estimated body mass index, and menopausal status between prior to/at first diagnosis and post-diagnosis mammograms and for initial %MD, study center, race (non-Hispanic white versus other), age at first diagnosis, age at menarche, number of full-term pregnancies, histologic type, stage, and estrogen receptor status of first diagnosis, chemotherapy, radiation, and tamoxifen use after first diagnosis