Table 3.

Risk of Invasive Breast Cancer (Randomization through Close-Out according to baseline breast tenderness and prior menopausal hormone therapy in the WHI Hormone Trials

Subgroup	CEE Trial							CEE+MPA Trial
	CEE		Placebo				P†	CEE+MPA		Placebo				P
	N	(%)‡	N	(%)	HR*	(95% CI)		N	(%)	N	(%)	HR	(95% CI)
Active vs. placebo: All participants	117	(0.28)	149	(0.35)	0.81	(0.63, 1.03)	0.08	293	(0.43	221	(0.34)	1.25	(1.05, 1.49)	0.01
Breast tenderness at baseline							0.37							0.03
No	91	(0.26)	125	(0.35)	0.75	(0.57, 0.98)		246	(0.41)	199	(0.35)	1.17	(0.97, 1.41)
Yes	24	(0.34)	23	(0.31)	1.00	(0.56, 1.79)		45	(0.56)	20	(0.27)	2.16	(1.29, 3.74)
Breast tenderness at baseline by prior MHT§							0.13							0.04
No breast tenderness/No prior MHT	42	(0.23)	75	(0.42)	0.56	(0.38, 0.82)		176	(0.40)	160	(0.38)	1.05	(0.85, 1.30)
No breast tenderness/prior MHT	49	(0.29)	50	(0.29)	1.02	(0.69, 1.52)		70	(0.45)	39	(0.27)	1.63	(1.11, 2.44)
Breast tenderness/No prior MHT	15	(0.40)	14	(0.39)	1.02	(0.49, 2.15)		31	(0.55)	13	(0.24)	2.29	(1.21, 4.56)
Breast tenderness/prior MHT	9	(0.27)	9	(0.24)	1.09	(0.42, 2.80)		14	(0.58)	7	(0.32)	1.80	(0.74, 4.76)
Severity of Breast tenderness at baseline							0.53							0.02
No breast tenderness	91	(0.26)	125	(0.35)	0.75	(0.57, 0.98)		246	(0.41)	199	(0.35)	1.17	(0.97, 1.41)
Mild tenderness	20	(0.36)	18	(0.30)	1.14	(0.60, 2.17)		37	(0.54)	18	(0.28)	1.96	(1.13, 3.54)
Moderate/severe tenderness	4	(0.27)	5	(0.37)	0.64	(0.16, 2.43)		8	(0.70)	2	(0.19)	4.55	(1.09, 30.82)

^*Hazard ratio from Cox proportional hazards models stratified by age, WHI Dietary Modification Trial treatment assignment, and subgroup.

^† P-values for main effect of treatment (boldface) and for interaction between treatment assignment and subgroup.

^‡ Annualized percentage.

^§ MHT = menopausal hormone therapy