. 2009 May 25;170(1):12–23. doi: 10.1093/aje/kwp115

Table 5.

Estimated Hazard Ratios for Selected Clinical Outcomes According to Use of Conjugated Equine Estrogens and Conjugated Equine Estrogens/Medroxyprogesterone Acetate Among Women who Began Hormone Therapy Immediately Following Menopause and Adhered to Their Hormone Therapy Regimen, From Combined Analysis of Women's Health Initiative Clinical Trial and Observational Study Data, 1993–2004

	Years From HT Initiation Among Women With No Prior Use of HT						Years From “Current” HT Episode^a Among Women With Prior Use of HT						5-Year^b Increase in Gap Time		Ratio^c of HR in Observational Study to HR in Clinical Trials
	<2		2–4		≥5		<2		2–4		≥5		5-Year^b Increase in Gap Time
	HR	95% CI	HR	95% CI	HR	95% CI	HR	95% CI	HR	95% CI	HR	95% CI	HR	95% CI	Ratio	95% CI
Coronary heart disease
CEE	1.12	0.55, 2.24	0.99	0.49, 2.00	0.60	0.35, 1.04	1.26	0.64, 2.46	1.52	0.81, 2.86	0.86	0.48, 1.52	0.98	0.85, 1.12	1.05	0.63, 1.76
CEE/MPA	1.42	0.76, 2.65	1.37	0.71, 2.67	1.24	0.61, 2.50	2.70	1.11, 6.52	1.10	0.46, 2.63	2.18	0.77, 6.19	1.01	0.84, 1.22	0.76	0.41, 1.42
Stroke
CEE	1.49	0.68, 3.28	2.45	1.06, 5.65	2.46	1.29, 4.70	1.43	0.61, 3.39	1.56	0.81, 3.03	2.39	1.25, 4.56	1.01	0.89, 1.15	0.46	0.25, 0.84
CEE/MPA	1.58	0.69, 3.66	2.17	0.99, 4.80	3.48	1.36, 8.96	1.73	0.53, 5.59	1.05	0.45, 2.45	1.48	0.51, 4.29	0.91	0.72, 1.14	0.33	0.14, 0.78
Venous thromboembolism
CEE	1.12	0.40, 3.17	0.80	0.30, 2.15	0.99	0.46, 2.14	4.09	1.28, 13.11	2.19	0.97, 4.95	1.56	0.73, 3.31	1.12	0.95, 1.33	0.61	0.30, 1.26
CEE/MPA	6.44	2.79, 14.85	3.15	1.47, 6.74	2.69	1.28, 5.63	1.65	0.70, 3.89	2.37	0.88, 6.43	1.64	0.41, 6.59	1.01	0.83, 1.23	0.62	0.32, 1.20
Invasive breast cancer
CEE	1.44	0.54, 3.84	1.15	0.57, 2.32	1.00	0.54, 1.84	1.63	0.68, 3.91	0.82	0.42, 1.57	0.91	0.49, 1.69	0.85	0.73, 0.98	1.07	0.60, 1.93
CEE/MPA	1.05	0.56, 1.97	2.18	1.31, 3.63	3.15	1.90, 5.20	1.79	0.84, 3.83	4.02	2.03, 7.98	3.14	1.46, 6.75	0.80	0.69, 0.93	1.06	0.66, 1.71
Invasive colorectal cancer
CEE	1.42	0.45, 4.52	1.91	0.44, 8.37	2.12	0.55, 8.16	0.95	0.32, 2.82	0.44	0.12, 1.66	4.43	1.13, 17.38	0.90	0.67, 1.21	0.32	0.09, 1.17
CEE/MPA	0.54	0.16, 1.77	0.46	0.16, 1.36	0.50	0.16, 1.58	0.53	0.13, 2.22	0.27	0.06, 1.28	0.71	0.17, 3.07	1.21	0.88, 1.68	1.85	0.68, 5.01
Invasive endometrial cancer
CEE/MPA	1.50	0.21, 10.67	1.60	0.40, 6.45	1.97	0.54, 7.13	0.33	0.04, 2.87	0.56	0.14, 2.31	0.82	0.17, 3.90	0.72	0.48, 1.09	1.13	0.35, 3.67
Hip fracture
CEE	0.46	0.04, 4.88	0.53	0.11, 2.51	0.69	0.19, 2.56	0.60	0.11, 3.24	0.13	0.02, 1.08	0.54	0.16, 1.76	1.01	0.77, 1.31	0.96	0.28, 3.32
CEE/MPA	0.35	0.10, 1.17	0.33	0.10, 1.10	0.22	0.07, 0.71	0.94	0.19, 4.58	0.26	0.05, 1.25	0.43	0.09, 2.07	1.29	0.94, 1.78	3.10	1.20, 7.98
Death from other causes^d
CEE	1.26	0.42, 3.81	1.04	0.43, 2.53	1.88	0.90, 3.93	1.29	0.51, 3.21	0.82	0.41, 1.63	3.16	1.53, 6.55	1.01	0.90, 1.14	0.38	0.18, 0.76
CEE/MPA	0.96	0.43, 2.14	0.70	0.34, 1.42	0.87	0.40, 1.88	0.18	0.02, 1.47	0.69	0.30, 1.61	0.75	0.26, 2.13	1.09	0.91, 1.31	0.97	0.48, 1.95
Global index^e
CEE	1.26	0.86, 1.83	1.23	0.87, 1.75	1.18	0.89, 1.57	1.29	0.90, 1.85	1.03	0.76, 1.39	1.53	1.15, 2.03	0.97	0.91, 1.03	0.70	0.53, 0.91
CEE/MPA	1.53	1.14, 2.05	1.56	1.18, 2.06	1.89	1.42, 2.49	1.28	0.86, 1.91	1.32	0.94, 1.85	1.43	0.96, 2.11	0.92	0.85, 0.99	0.86	0.67, 1.11
Total invasive cancer
CEE	1.72	1.04, 2.83	1.07	0.68, 1.69	1.17	0.80, 1.70	1.12	0.70, 1.81	0.74	0.49, 1.11	1.40	0.96, 2.02	0.91	0.83, 0.99	0.77	0.54, 1.11
CEE/MPA	1.14	0.78, 1.67	1.49	1.08, 2.07	1.82	1.31, 2.53	1.01	0.64, 1.61	1.48	0.99, 2.22	1.42	0.90, 2.25	0.88	0.80, 0.97	1.06	0.79, 1.43
Total mortality
CEE	1.62	0.75, 3.53	1.26	0.66, 2.41	1.35	0.82, 2.24	2.19	1.08, 4.47	1.06	0.62, 1.83	1.92	1.16, 3.19	0.97	0.88, 1.07	0.53	0.33, 0.86
CEE/MPA	0.83	0.43, 1.60	0.89	0.50, 1.60	1.13	0.59, 2.16	0.55	0.18, 1.63	0.84	0.43, 1.66	0.90	0.38, 2.14	1.09	0.93, 1.27	0.76	0.43, 1.37

Abbreviations: CEE, conjugated equine estrogens; CI, confidence interval; HR, hazard ratio; HT, hormone therapy; MPA, medroxyprogesterone acetate.

“Years from ‘current’ HT episode” refers to years from randomization in the clinical trials and years from the beginning of the HT episode ongoing at the time of enrollment in the observational study (see Materials and Methods).

HRs for CEE or CEE/MPA were estimated to change by this factor with a 5-year increase in gap time from menopause to first use of HT.

Estimate of the overall ratio of CEE or CEE/MPA HRs between the observational study and the clinical trials, after controlling for the factors described in the text (see Materials and Methods).

Death from causes other than cardiovascular disease, breast cancer, colorectal cancer, endometrial cancer, or hip fracture.

The global index is the time to first occurrence of the outcome listed above it (with breast, colorectal, and endometrial cancer, including noninvasive cancer).