. Author manuscript; available in PMC: 2021 Nov 11.

Published in final edited form as: Breast Cancer Res Treat. 2017 Feb 4;162(3):419–425. doi: 10.1007/s10549-017-4127-6

Table 2.

Relationship between Breast Density and Aspirin Use

	Aspirin Non-Users N = 20889	Aspirin Users N = 5111	OR (95% CI)^*
Mammographic breast density
Entirely fat	2006 (9.6)	861 (16.9)	1.15 (1.04 – 1.27)
Scattered fibroglandular	9346 (44.7)	2859 (55.9)	1.00 (Reference)
Heterogeneously dense	8480 (40.6)	1312 (25.7)	0.84 (0.78 – 0.92)
Extremely dense	1057 (5.1)	79 (1.6)	0.73 (0.57 – 0.93)
			P_trend<0.001
Dichotomized breast density
Non-dense	11352 (54.3)	3720 (72.8)	1.00 (Reference)
Dense	9537 (45.7)	1391 (27.2)	0.82 (0.76 −0.89)

Logistic regression results for model with aspirin use as the outcome and BI-RADS density as a categorical variable of interest, adjusted for age (continuous, 1^st and 2^nd order terms), bmi, and race.