|
|
|
Overview Page 3
Fractures remain
common in elderly women
on continuous estrogen
A study published in the November 2002
issue of Archives of Internal Medicine
demonstrated that, although estrogen use
is associated with a lower prevalence of
fractures, osteoporosis and fractures
remain common even in older women
who have used estrogen continuously
since menopause.1
Half of all postmenopausal women will have
an osteoporosis-related fracture during their
lives and 15% will experience a hip fracture.2,3
Previous observational studies have
shown that women who use estrogen are
somewhat protected from fractures, but they
have not shown the extent to which estrogen
users remain at risk. The investigators in
the present study examined data from the
Study of Osteoporotic Fractures, a prospective
cohort study of 8816 women 65 years
of age and older. The study design included
10 years of follow-up. The primary objective
was to determine the long-term incidence
of fractures among women who (1)
had used estrogen continuously since
menopause, (2) were past users of estrogen,
(3) were partial users (they had taken estrogen
for at least one year but not continuously),
or (4) had never taken estrogen. Partial
users were further categorized based on
current or past use. Of the total of 8816
enrolled women, 373 had used estrogen
continuously, 2466 had used estrogen partially
from menopause until baseline (926
of them were using estrogen at baseline),
and 5977 had never used estrogen for at
least one year.
Results
After adjusting for age and weight using the
Cox proportional hazards model, the ten-year
rate for any nonvertebral fracture for
continuous estrogen users was 19.6%. The
rate was similar for current partial users
(22.4%), but lower than that for past users
(29.6%) and never users (30.9%; p<0.001).
The ten-year rate for hip fractures was 2.8%
for both continuous and current partial
users, 5.5% for past users and 5.3% for
never users (p<0.05; Figure 1). For wrist
fractures, the ten-year rate was 3.3% for
continuous users, 3.5% for current partial
users, 6.4% for past users, and 7.5% for
never users (p<0.05).
To determine if the continuous users who
sustained fractures were different from those
who did not, the investigators compared
their baseline characteristics. They found
that estrogen users who had fractures were
slightly older, were more likely to have
smoked cigarettes, and more likely to take
sedative or anxiolytic medications.
The results of this study were consistent
with previous findings that women who
take estrogen have a lower risk of fractures
than those who do not. Nevertheless,
approximately one in five women in the
continuous user group experienced a fracture
during a ten-year period, indicating
that clinicians cannot assume that women
using estrogen are fully protected from
osteoporotic fractures.
REFERENCES
-
Nelson HD, Rizzo J, Harris E, et al. Osteoporosis
and fractures in postmenopausal women using
estrogen. Arch Inter Med. 2002;162:2278-2284.
-
Melton LJ, Kan SH, Frye MA, et al. Epidemiology
of vertebral fractures in women. Am J Epidemiol.
1989;129:1000-1011.
-
Barrett JA, Baron JA, Karagas MR, et al.
Fracture risk in the U.S. Medicare population.
J Clin Epidemiol. 1999;52:243-249.
Return to [VCU-CME.org]
|
|
|
