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

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HORMONE THERAPY USE AND RISK OF CARDIOVASCULAR DISEASE
menopause, there were 72 (0.32%) cases ment of vasomotor symptomswith hor- decreasing risk is confounded by dimin-
of breast cancer while taking CEE + MP'A mone therapy in younger women reishing compliance over time. Curent or
compared with 57 (0.28%) cases while mains an option, the reverse might past hormone users and never users ap-
takingplacebo (HR, 1. 19: 95% Cl, 0.84- apply io older women. Rather, the prespeared to have similar trends toward in-
1.70). By contrast, the increasing absoence of moderate or severe vasomotor creasing risks by years since menolute
risks of CHD in older women or symptoms at older ages might signal the pause during the rial, providing indirect
women more distant from menopause need for identifecaion and treatment of evidence that longer duration of use is
(most marked in women aged >70 years risk factors for CHD. Although CHD not protective. It is not feasible to test
or 220 years past menopause). to- risk factors were more frequent in hormone effects over very long periods
gether with their increased risks of stoke. women with vasomotor symptoms, of use in clinical trials, and observa-
breast cancer, and venous thromboem- analyses adjusting for these factors did tional studies have yielded conflicting rebolism,
would in general contraindi- not change the trend statistic, suggestsuIts.'cate the use of honnones for disease preing that hormone therapy interactions
vention in these groups.
with other unmeasured risk factors in
The findings for vasomotor symp- women with vasomotorsymptoms may
toms are itnguingand ofpotential im- underlie the increasing risk in women
portance to clinicians hut need confir- more distant from menopause.
mation. The higher risks in women The current analyses are most perti-
more distant from menopause apnent to the effects of initiation of exogpeared
to be concentrated in the small enous hormone use but also provide
subset of women with moderate orse- some limited information regarding the
vere vasomotor symptoms. It is pos- potential effects of prolonged use, taksible
that vasomotor symptoms in reing into account indicators of horcently
menopausal women represent mone status at trial enrollment. Within
the reaction of vessels with normal en- the relatively short trial durations, CHD
doihelial function to estrogen with- risk related to hormone therapy apdrawal
but persistent symptoms may peared to decrease over time. How-
signify something different in older ever, the significance of this trend over
women. Ifconfirmed elsewhere (eg, by time depends on both the initial in-
reanalyses of existing observational crease in risk, as well as the subsequent
studies and clinical trials), the clinical decrease, and hence may partially rep-
implication might he that while treatresent a survivor effect. In addition, the
0 "Unlike statindnugs, which have
beneficial effects for both atherosclerosis
and clinical events irrespective of the
underlying state of the arteries," 1 hormone
therapy has a putative beneficial
effect on early atherosclerosis," no eflect
on advanced atherosclrosisa 2 and an
early increase in risk of CHD events
when advanced atherosclerosis may be
present.'- 1 " Because age-related progression
of atherosclerosis is likely to
continue even in the face of hormone
therapy, use over decades could potentially
result in an eventual increase in
CHD events. Hence, even if ongoing
imaging trials confirm a slowing of early
atherosclerosis, 011 ' it would be unwise
to extrapolate such findings to clinical
benefit with continued use into old age.
These analyses are based on systematically
ascertained outcomes in a set-
Table 7. Cardiovascular and Global Index Events in Subgroup of Partiopants With Moderate or Severe Vasomotor Symptoms at Baseline in
the Combined Trals
Year, Since Melnopause