Alzheimer's and Menopause
A story from
Medical News Today noted that a variant of the gene ApoE, ApoE4, is carried in
15 to 20 percent of Americans, putting them at increased risk of developing
Alzheimer’s disease. In a study
from PLOS ONE, lead author Natalie
Rasgon, MD, PhD, professor of psychiatry and behavioral sciences at Stanford
University’s School of Medicine and director of the Stanford Center for
Neuroscience in Women’s Health along with fellow authors, recognized a
connection between the gene variant and hormone therapy in menopausal women. As
it turns out, hormone therapy allowed menopausal women at an elevated risk of
Alzheimer’s disease to deter the effects of biological aging.
“We know from numerous studies that ApoE4 is a major genetic
risk factor for cognitive decline, Alzheimer’s disease and early mortality,” said
Emily Jacobs, PhD, first author of the study and postdoctoral fellow at Harvard
Medical School in the Medical News today story. “We wanted to see whether an
accelerated rate of biological aging explained this risk.”
According to the story, the study examined roughly 70 “relatively
well-educated, high-functioning women” between the ages of 45 and 65 as they
were divided into two groups, half of which continued hormone therapy while the
other half stopped. Fellow co-author, Elizabeth Blackburn, PHD, professor of
biochemistry and biophysics at UCSF, won the Nobel Prize in 2009 for work on telomeres
-- “intracellular features” that “act as biological clocks.” The telomeres were
observed in each of the women as the two-year study continued. By examining the
length of the telomeres -- in this case:
the longer, the better -- the research
team was able to discover that “hormone therapy effectively zeroed out ApoE4’s
negative influence over time,” while the carriers who had stopped hormone therapy
experienced “accelerated biological aging.”
“Our take-home findings from this study were, first, that
ApoE4 carriers are at greater risk of biological aging, which is associated
with negative health outcomes,” explained Rasgon. “And, second, that if you
were a postmenopausal ApoE4 carrier, being on estrogen therapy was a good thing
for telomere length, and established measure of biological aging at the
cellular level. This brings us a step closer to being able to identify which
women will benefit the most from estrogen replacement therapy.”
As research continues, more and more is discovered and understood
about our genetic code. The knowledge of potential risk for diseases could be
beneficial not only for menopausal woman who could be provided with a more
effective form of preventative treatment for Alzheimer’s disease, but also for
people at risk for any number of diseases -- essentially allowing time for the necessary
life style changes that could aid in prevention.