The Role of Estrogen in Memory Loss
By Janna Gordon, RPh
brought to you by Bellevue Pharmacy, a ProjectAWARE
Memory loss is a growing problem in the elderly population. By
the year 2050, it's estimated that 13 million Americans will be
living with Alzheimer's disease.1 There are a variety
of prescriptions available to treat Alzheimer's, including Aricept,
Namenda, Reminyl, etc.2 Are there any other drugs that
may be effective for treatment? It's common for most female patients
to be on hormone replacement for treatment of menopause. Can estrogen
be used to treat Alzheimer's disease or prevent memory loss in elderly
patients? What is the role of estrogen in treating a decline in
patient's memory and cognition?
There are a few studies available that oppose estrogen for treatment
of Alzheimer's and other studies that propose a benefit in using
estrogen. The theory behind estrogen's benefit in this patient population
is based on the various locations of estrogen receptors throughout
the body. Estrogen receptors are located in several areas of the
brain and the limbic system, which are both important in memory
involvement. Estrogen promotes growth of neuronal processes, neuronal
differentiation, and formation of synaptic connections.3
With all of estrogen's involvement within the brain and limbic system
it's easy to assume that it would have a benefit in memory loss
However, the Women's Health Initiative Memory Study (WHIMS) opposed
the use of estrogen for prevention of dementia or cognitive decline.
It was reported that estrogen did not decrease the risk of developing
dementia/cognitive impairment. In addition, this study reported
an increase risk of developing dementia/cognitive impairment.
However, there were a few areas that weakened the study. The participants
in the study were between the ages of 65 and 79 years old.1
There's a possibility within this age range, irreversible neuronal
degeneration may already be present. Therefore, late initiation
of estrogen probably wouldn't be beneficial in this patient population.
Also, a significant portion of the estrogen group in the study had
comorbidities, hypertension and diabetes, that increased their risk
for vascular damage (i.e. dementia).1 These patients
are already at a disadvantage of seeing benefits from estrogen because
of the vascular damage. Lastly, the study used pooled data to show
significant results against the use of estrogen for dementia.1
Without pooled data, there wasn't any significant difference in
the increase in patients with dementia in the estrogen group versus
the patients not on estrogen.
There still isn't a definite answer for the use of estrogen in
treating memory loss or cognitive impairment. There is inconsistency
between the studies available and the role of estrogen in memory
loss. Most practitioners will agree that estrogen is not monotherapy
for treating Alzheimer's disease or dementia. However, if a patient
is currently experiencing menopausal symptoms, estrogen may have
the added benefit of preventing memory loss/cognitive impairment
while treating menopausal symptoms.
- Shumaker SA, et al. Conjugated equine estrogens and incidence
of probably dementia and mild cognitive impairment in postmenopausal
women: women’s health initiative memory study. JAMA. 2004;291(24):2947-58.
- Brief summary: Practice
parameter: management of dementia (an evidence-based review).
Report of the Quality Standards Subcommittee of the American Academy
of Neurology. National Guideline Clearinghouse. Department of
Health and Human Services. (Accessed 16 January 2006)
- Sherwin BB. Can estrogen keep you smart? Evidence from clinical
studies. J Psychiatry Neuroscience. 1999;24(4):315-321.
For questions and further information, contact Bellevue