Table 4.

Annualized Rates and Multivariable-Adjusted Risk of Invasive Breast Cancer Among women with and without New-Onset Breast Tenderness at 12-Month Follow-up in the WHI Estrogen-Alone and Estrogen + Progestin Trials

HT Trial Arm	CEE Trial							CEE+MPA Trial
	Experienced new-onset breast tenderness		Did not experience new- onset breast tenderness		HR†	(95% CI)	P‡	Experienced new-onset breast tenderness		Did not experience new- onset breast tenderness		HR	(95% CI)	P
	Cases (N at risk)	(%)*	Cases (N at risk)	(%)				Cases (N at risk)	(%)	Cases (N at risk)	(%)
All participants (Active and placebo)	42 (1779)	(0.34)	158 (6202)	(0.30)	1.04	(0.74, 1.48)	0.81	116 (3231)	(0.51)	301 (10149)	(0.35)	1.22	(0.97, 1.53)	0.09
Active	22 (1208)	(0.26)	62 (2748)	(0.26)	0.98	(0.62, 1.53)	0.92	93 (2471)	(0.53)	141 (4380)	(0.37)	1.33	(1.02, 1.72)	0.03
Placebo	20 (571)	(0.50)	96 (3454)	(0.34)	1.15	(0.70, 1.88)	0.57	23 (760)	(0.43)	160 (5769)	(0.34)	1.07	(0.70, 1.63)	0.76

^*Annualized rates

^† Hazard ratio from Cox proportional hazards models comparing risk of breast cancer among women with versus without new-onset breast tenderness. Cox proportional hazards models are adjusted for HT randomization assignment, age, ethnicity, alcohol consumption, smoking, body mass index (linear and quartiles), physical activity (linear and quartiles), parity, age at first birth, breast feeding, years of age at menopause, Gail model breast cancer risk (linear and quartiles), bilateral oophorectomy, menopausal hormone therapy use prior to trial participation. This table displays hazard ratios for women without baseline breast tenderness.

^‡ P-values for comparison of hazard ratios among women with new-onset breast tenderness and women without new-onset breast tenderness.