If Alice had stayed in Wonderland long enough to collect
her pension cheque from the Queen of Hearts, she may have
sadly ended up like the Mad Hatter. One-third of women
over the age of 65 develop dementia, with Alzheimer's
disease being the most common form.
But there's new hope for these
women — a study reports that taking raloxifene
may have improved Alice's odds of dodging dementia.
The selective estrogen receptor modulator (SERM) used
for the prevention and treatment of osteoporosis might
help keep both brains and bones healthy.
"Women receiving 120mg/day of raloxifene
had a 33% lower risk of mild cognitive impairment,"
according to the authors of a multicentre trial funded
by Eli-Lilly and published in the April issue of the
American Journal of Psychiatry.
The randomized, placebo-controlled
Multiple Outcomes of Raloxifene Evaluation (MORE) trial
was designed primarily to study vertebral fractures
and bone mineral density. As a secondary endpoint, the
researchers evaluated the incidence of mild cognitive
impairment and dementia as declining serum estrogen
levels following menopause may contribute to Alzheimer's
disease in older women.
Meta-analyses of observational
studies have shown a 30% risk reduction for developing
dementia in women receiving postmenopausal estrogen
therapy, but until now the findings in large randomized
trials have been less impressive.
Along with her colleagues, Dr Kristine
Yaffe at the University of California, San Francisco,
selected 7,705 postmenopausal women with osteoporosis
for the main study. Of those, 7,023 were screened for
dementia at the outset of the trial.
Participants were divided equally
among the three treatment groups: 120mg or 60mg raloxifene
daily or placebo. All of the women were also asked to
take 500mg calcium and 400 - 600IU vitamin D daily.
During the three-year study period, clinical and cognitive
assessments were repeated annually. Women who developed
cognitive impairment were kept in the study and monitored
for continuing decline.
MAKE
NO BONES ABOUT IT
At the end of the study, the 5,386 women who remained
were again tested for dementia. Researchers found "while
treatment with 120mg/day of raloxifene reduced the risk
of mild cognitive impairment, there was no significant
benefit from treatment with the lower dose of 60mg/day."
However, both 60mg and 120mg raloxifene daily were effective
for osteoporosis.
The researchers suggest that higher
doses of raloxifene are needed to achieve therapeutic
concentrations of the drug in the brain. Although there's
no doubt that this SERM shows promise, the authors caution
that they can't determine whether 120mg/day of raloxifene
prevented mild cognitive impairment or delayed its onset.
Given that mild impairment frequently
progresses, even a delay in onset would provide precious
time to those with the condition and to their caregivers.
And with the prevalence of Alzheimer's disease expected
to quadruple over the next 45 years, this drug could
give thousands of Canadian women a chance to improve
their odds of staying physically and mentally fit.
Am J Psychiatry Apr, 2005;162(4):683-90
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