Researchers Report
That Combination Therapy
Is Effective for Older Women with Osteoporosis
Posted June 30, 2003
University of Pittsburgh researchers have found that elderly women with
osteoporosis can significantly and safely improve their bone mass with
a combination therapy of hormone replacement and the bisphosphonate alendronate
(Fosamax). Their findings are published in the May 21 issue of the Journal
of the American Medical Association.
"Our study found that a combination therapy of hormone replacement
and alendronate was well tolerated by elderly women with low bone mass.
After three years of treatment, these women showed significantly greater
increases in bone mass than we saw in similar women taking only one of
the therapies," said lead author Dr. Susan Greenspan, professor
of medicine at the University of Pittsburgh School of Medicine and director
of the Osteoporosis Prevention and Treatment Center at the University
of Pittsburgh Medical Center. "Combination therapy is a safe, viable
option for postmenopausal women who have been unable to improve their
bone density with an individual therapy, or in women with osteoporosis
severe enough to require a greater increase in bone density."
Earlier research has suggested similar results with younger women, but
up to now little data were available on the effectiveness and safety
of combination therapy in older, post-menopausal women. The study was
conducted with 373 women aged 65 to 90 years. At baseline, participants
as a group had bone mass thin enough to be classified as osteopenia,
a precursor of osteoporosis. Thirty-four percent of the women had osteoporosis.
Participants were evenly randomized to receive hormone replacement therapy
(HRT) (conjugated estrogen with or without medozyprogesterone) plus alendronate,
HRT alone, alendronate alone, or placebo. All received calcium and vitamin
D supplements.
After three years, dual-energy X-ray absorptiometry (DXA) scans showed
that participants taking combination therapy had greater improvements
in bone mineral density (BMD) at the hip and spine than did those participants
taking HRT or alendronate alone, or placebo. For instance, the mean increase
in BMD at the hip was 5.9 percent with combination therapy, 4.2 percent
with alendronate, 3.0 percent with HRT and 0.0 percent with placebo.
At the lumbar spine the mean increases in BMD were 10.4 percent with
combination therapy, 7.7 percent with alendronate, 7.1 percent with HRT
and 1.1 with placebo. Also, in comparing HRT with alendronate, researchers
found that participants taking alendronate alone had greater improvements
in BMD at the hip.
The university news release explains that while the study was not designed
to examine fractures as an outcome, a higher bone density is usually
associated with fewer fractures.
"We applied a logistic model to our data and determined that combination
therapy would provide an additional 10 percent reduction in fracture
over HRT alone and an additional 8 percent over alendronate alone,"
said Dr. Greenspan. "These results can help elderly women decide
whether the potential risk inherent in HRT use is worth taking to reduce
the risk of fracture."