CloseClose
Find a Drug
Advanced Search

Professional

Estring

Clinical Pharmacology
font size

Clinical Pharmacology

Estring

For those outcomes included in the WHI "global index" that reached statistical significance, the absolute excess risk per 10,000 women-years in the group treated with CE alone was 12 more strokes, while the absolute risk reduction per 10,000 women-years was 6 fewer hip fractures. The absolute excess risk of events included in the "global index" was a non significant 2 events per 10,000 women-years. There was no difference between the groups in terms of all-cause mortality. (See BOXED WARNINGS, WARNINGS, and PRECAUTIONS.)

Final centrally adjudicated results for CHD events and centrally adjudicated results for invasive breast cancer incidence from the estrogen-alone substudy, after an average follow-up of 7.1 years, reported no overall difference from primary CHD events (nonfatal MI, Silent MI and CHD death) and invasive breast cancer incidence in women receiving CE alone compared with placebo (see Table 2).

The estrogen-plus-progestin substudy was also stopped early. According to the predefined stopping rule, after an average follow-up of 5.2 years of treatment, the increased risk of breast cancer and cardiovascular events exceeded the specified benefits included in the “global index.” The absolute excess risk of events included in the “global index” was 19 per 10,000 women-years (RR 1.15, 95% nCI 1.03-1.28).

For those outcomes included in the WHI “global index” that reached statistical significance after 5.6 years of follow-up, the absolute excess risks per 10,000 women-years in the group treated with CE/MPA were 6 more CHD events, 7 more strokes, 10 more PEs, and 8 more invasive breast cancers, while the absolute risk reductions per 10,000 women-years were 7 fewer colorectal cancers and 5 fewer hip fractures. (See BOXED WARNINGS, WARNINGS, and PRECAUTIONS.)

Results of the estrogen-plus-progestin substudy which included 16,608 women (average of 63 years, range 50 to 79; 83.9 percent White, 6.8 percent Black, 5.4 percent Hispanic, 3.9 percent. Other, are presented in Table 3 below. These results reflect centrally adjudicated data, after an average follow-up of 5.6 years .

TABLE 3: RELATIVE AND ABSOLUTE RISK SEEN IN THE ESTROGEN- PLUS-PROGESTIN SUBSTUDY OF WHI AT AN AVERAGE OF 5.6 YEARa

Event c Relative Risk CE/MPA vs. placebo
(95% nCIb)		 Placebo
n = 8,102		 CE/MPA
n = 8,506
Absolute Risk per 10,000 Women-Years
CHD events 1.24 (1.00-1.54) 33 39
  Non-fatal MI 1.28 (1.00-1. 63) 25 31
  CHD death 1.10 (0.70-1.75) 8 8
  All strokes 1.31 (1.02-1.68) 24 31
  Ischenic Stroke 1.44 (1.09-1.90) 18 26
Deep vein thrombosis 2.13 (1.43-2.67) 13 26
Pulmonary embolism 2.13 (1.45-3.11) 8 18
Invasive breast cancerc 1.24 (1.01-1.54) 33 41
Invasive Colorectal cancer 0.56 (0.38-0.81) 10 16
Endometrial cancer 0.81 (0.48-1.36) 7 6
Cervical cancer 1.44 (0.47-4.42) 1 2
Hip fracture 0.67 (0.47-0.96) 16 9
Vertebral fracture 0.65 (0.46-0.92) 17 11
Lower arm/wrist fractures 0.71 (0.59-0.85) 62 44
Total fractures 0.76 (0.69-0.83) 199 152
a Results are based on centrally adjudicated data. Mortality data was not part of the adjudicated data;however, data at 5.2 years of follow-up showed no difference between the groups in terms of all-causemortality (RR 0.98, 95% nCI 0.82-1.18).
b Nominal confidence intervals unadjusted for multiple looks and multiple comparisons.
c Includes metastatic and non-metastatic breast cancer, with the exception of in situ breast cancer.

Women's Health Initiative Memory Study

Brand Name: Estring
Generic Name: Estradiol Vaginal Ring
Bookmark this page:
WebMD Symptom Checker - Start Here Diseases & Conditions: A comprehensive A-Z listing
WebMD Resources

Menopause Myths Menopause Myths
A generation ago, no one talked about menopause. Today it's openly discussed. But some common menopause myths persist. See more WebMD Videos »

Privacy Policy

Women's Health

Find out what women really need.