Am I Losing My Mind? No, It’s Just Your Estrogen…
May 9, 2023
While forgetting where we put our keys, why we walked up the stairs, or what we needed at the grocery store once we got there are often common characteristics of life stress and aging, they are not necessarily hallmark indicators of dementia and Alzheimer’s disease. Yet, many people begin to worry, as they age, that these lapses in memory may mean the beginning of the end.
This fear is merited. According to the World Health Organization, there are currently around 50 million people worldwide living with dementia. This number is expected to triple by 2050. So, since dementia, and its close cousin Alzheimer’s disease, are not going away anytime soon, understanding the what, the who, the why, and the when behind this alarming disease can help both researchers and their patients understand the best preventative approach.
To find a doctor near you, simply search the Bio-Identical Hormone Therapy (BHRT) Provider Directory.
Normal aging of the brain is accompanied by changes in brain structure, function, and metabolism. These are common changes that can happen in the absence of dementia. However, when the brain experiences critical levels of neuronal loss, accumulation of intracellular neurofibrillary tangles, and extracellular senile plaques in hippocampus and neocortex, people begin to experience the more severe symptoms associated with dementia and its different subtypes.
Simply put, dementia is the decline in mental function that is often irreversible. The catchall term, dementia, actually encompasses several different disorders that cause memory loss, personality changes, and compromised reasoning. These disorders include Alzheimer’s disease, vascular dementia, Lewy body dementia, Parkinson’s dementia, frontotemporal dementia, and chronic traumatic encephalopathy.
Disorders grouped under the general term “dementia” are caused by abnormal brain changes. These changes trigger a decline in cognitive abilities, severe enough to impair daily life and independent function. They also affect behavior, emotions, and relationships.
Although men suffer from dementia, women tend to suffer the brunt of the disease, with Alzheimer’s disease being the most common form. According to the Alzheimer’s Society, women account for every two out three people diagnosed with dementia. Through brain scans, researchers have found that women in mid-life had 30 percent more Alzheimer’s-related plaques, 22 percent lower brain glucose metabolism, meaning lower energy levels in the brain, and about 11 percent more brain shrinkage than men of the same age. Compounding this, women live longer which puts them in an age bracket where dementia is far more likely.
Although researchers have not pinpointed the exact reason women are more susceptible than men to the ravages of dementia, one of the likely culprits many physicians and researchers have identified is the fact that women stop producing estrogen at menopause and its absence has far reaching effects.
On the other hand, men continue to produce testosterone, the male sex hormone, throughout their entire lives, which is converted into estrogen inside the brain cells. This allows men to continue to enjoy its neuroprotective effect.
Estrogen is a hormone that plays a critical role in the development and function of the female reproductive system. It also has a significant impact on other parts of the body too, including the brain. It is well established that estrogen receptors are widespread throughout the brain, including the cerebral cortex, midbrain, hippocampus, brain stem, hypothalamus, and pituitary gland, with the highest concentration of receptors found in the hypothalamus, pituitary, and amygdala.
Overall, estrogen plays a crucial role in the development and function of the brain, and changes in estrogen levels can have a significant impact on brain function and behavior. Estrogen’s effect on the female brain includes:
- Neuronal growth and development: Estrogen promotes the growth and development of neurons in the brain, particularly in areas related to memory and cognition.
- Neuroprotection: Estrogen has been shown to have neuroprotective effects, meaning it helps to protect neurons from damage and death.
- Neurotransmitter regulation: Estrogen helps to regulate the levels of neurotransmitters in the brain, which are important for mood, behavior, and cognitive function.
- Mood regulation: Estrogen has been linked to mood regulation, and low levels of estrogen have been associated with symptoms of depression and anxiety.
- Cognitive function: Estrogen has been shown to improve cognitive function, including memory, attention, and executive function.
- Sleep regulation: Estrogen plays a role in regulating sleep, and low levels of estrogen have been linked to sleep disturbances.
Knowing estrogen is essential throughout a woman’s life, can estrogen replacement actually change the course of memory decline and the possibility of future dementia and Alzheimer’s disease?
Exciting new studies seem to suggest that the answer is YES!
Recent research found that women who had undergone a bilateral oophorectomy (removal of the ovaries) had a decrement in cognitive performance postoperatively which was related to a decrease in their plasma levels of circulating sex steroids, and the subsequent administration of estrogen improved scores on cognitive tasks.
Another longitudinal study reported that a history of estrogen use during the postmenopausal period was associated with higher scores on verbal memory, language and abstract reasoning. Other research indicates that this improvement only seems to get better over time. In a 2-year follow-up period, estrogen users increased their scores on verbal memory tasks whereas nonusers showed a decrease in their scores.
These estrogen-related improvements go above and beyond verbal tasks. Research has shown that hormone replacement therapy can help with nonverbal aspects of cognitive function in healthy postmenopausal women, too. Women on long-term hormone replacement therapy performed better than postmenopausal women who had never taken hormones on the Benton Visual Retention Test (a test for short-term visual memory, visual perception, and constructional skills). In a group of healthy postmenopausal women receiving transdermal estrogen for 3 weeks, researchers found improvements in verbal memory and in visuospatial ability. A recent functional imaging study demonstrated estrogen-induced alterations in brain activation patterns during verbal and nonverbal working memory tasks in frontal and parietal regions in postmenopausal women.
As societies age, the question of how best to preserve women’s cognitive health during and after menopause is becoming more urgent. When we consider that in 1990, nearly half a billion women were 50 or older (the age when menopause typically begins). Today there are almost twice as many.
That being the case, researchers are beginning to agree that there is a window of opportunity for hormone replacement therapy. If you prescribe hormones to women in their sixties, after they have experienced a long bout of hormonal absence, many disease states, like osteoporosis, dementia, or heart disease, may have potentially set in, making hormones less effective.
In their very nature, hormones are protective and preventative, and although they can help ameliorate certain disease states, nothing is better or more effective than a good dose of deterrence. The director of Center for Innovation in Brain Science at the University of Arizona, Roberta Diaz Brinton, PhD, summed it up best by saying, “The key is that hormone therapy is not a treatment, but it’s keeping the brain and this whole system functioning, leading to prevention. It’s not reversing disease; it’s preventing disease by keeping the brain healthy.”
It’s also important to understand that certain types of hormones are better suited to the female body than others. In a recent study, natural, bio-identical hormones were shown to induce a greater risk reduction than the use of synthetic hormones for combined neurodegenerative diseases.
What You Can Do…
Basic research strongly suggests that estrogen is key to maintaining healthy brain function. Understanding the disease is one thing, but what is truly empowering is understanding preventative steps you can take now to potentially prevent or prolong its deleterious effects in your future.
If you’re interested in learning more about it, ask your physician whether you’re a good candidate for hormone therapy for cognitive health. Your brain will thank you for it!
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