Bioidentical Hormones - U.S. Senate Special Committee on Aging

Evidence-based Cardiology
A second large trial being conducted In the United Kingdom
and New Zealand, known as the Woment Intervention Study
of long-Duration Oestrogen after the Menopause (WISDOM),
is enrolling women aged 50-64 and randomizing women
with a uterus to CEE 0-625 mg/day plus MPA 2.5 mg/day or
placebo, and women who have had a hysterectomy to CEE
0-625 mg/day, CEE 0.635 mg/day plus MPA 2-5 mg/day, or
placebo.' Up to 34000 women will be enrolled. The primary
analysis will compare CEE plus MPA to placebo, and the secondary
analysis will compare CEE plus MPA to CEE alone.
The primary outcome of Interest is combined CHD and stroke.
Secondary prevention
Obseavafonal sfulies
Observational studies in women undergoing angioplasty or
coronary artery bypass grafting (CABG) have found that
use of Dostmnenopausal hormone rheirs iv assated
with lower rates of cardiovascular events and improved
survival. 3 " A retrospective analysis of postmenopausal
women undergoing angfoplasty found that 12% of patients
taking hormones had cardiovascular events over 7 years
of follow up, compared to 35% of non-users. 3 ' A second
similar study found that inhospital and 2 year mortality after
angioplasty was lower In hormone user38 In women
undergoing CABG, one study found that hormone use was
associated with a 62% survival benefit; however, this was
not confirmed in a subsequent study3.9,4 Several observadonal
studies have compared the experience of women
currently on hormone therapy and who suffer a myocardial
infarcdon with those who were not on hormone therapy at
the time of the myocardial iznfastion. -" These studies
have consistently found better outcomes for women who
were currently on hormone therapy as the time of the evenL
The largest study of inhospital mortality was performed
prospectively In 114724 womed aged over 55 who were
entered Into the National Reis"y of Myocardial Infarction-3. 4 '
At the time of hospitalization, 6-4% of women reported
current use of hormone therapy. There were significant differences
between hormone users and non-users. Hormone
users were younger, more likely to be white, less likely to
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have a history of diabetes, heart failure, prior myocardial
Infaretion, and prior stroke compared to non-users, but were
more likely to have high blood cholesterol and family history
of CAD, or to smoke. Hormone users were also more
likely to receive aggressive inhospital care Including anlography,
angioplasty, bypass grafting. reperfusion therapy,
aspirin, heparin, i3 blockers, and nitrates (Table 20.2).
Complication -rates were similap in users and non-users;
however, after adjustment for the potential confounders, hormone
use was associated with a reduced odds of Inhospital
mortality (0-65, 95% CI 0-59-0 72). The association was
strongest in the youngest group of women (age 55-64 years).
The authors acknowledge that some or all of this apparent
survival benefit could be due to one or more sources of bias
- for example, residual differences between users and nonusers
or the healthier profile that decreased mortality may
also have Increased the likelihood of taking hormone therapy;
or the hormone users may have received care at hospitals
with greater experience of myocardial infarction care; or
hormone users may have been better at compliance with
treatment and may thus have an improved survival. The
many differences in patient characteristics and inhospital
treatment observed between hormone users and non-users
illustrate the difficulties of Interpretation of observational
studies.
Three observational studies have suggested that recent
initiation of hormones after the index myocardial infarction