- We were looking at the aging brain, and we were trying to understand why Alzheimer's disease affects more women than men. We know today that out of every three patients affected by Alzheimer's disease, two are women. And frankly, we've known this for a long time, since 1994. And the question was always is it just that women live longer than men, or is there something more that could really explain this two to one ratio, where out of every three patients, two are women, which really means that for every man suffering from Alzheimer's disease, there are two women? Is there's something about women that can explain why Alzheimer's disease affects more women than men? And the answer was almost always, "Well, sweetheart, women live longer than men, "and Alzheimer's disease is a disease of old age. "So unfortunately, more women than men "end up with Alzheimer's disease." And then a lot of my research and other people's research has clarified that Alzheimer's disease is not a disease of old age. Alzheimer's is a disease of middle age, a disease of midlife that starts in the brain that creates negative changes in the brain in midlife with symptoms that appear or become clinically evident in late life. So that completely changed the question. The question then became, ah, so what happens to women and not to men in midlife that could potentially link to the increased risk of Alzheimer's disease? And by studying this connection, we actually landed on menopause. We were studying middle aged individuals, men and women, and middle age is any age between 35 and 65, so is a wide 30 year gap. And we have women in the study, we have men in the study, and we use a lot of brain imaging techniques to look at the way that the brain ages over time, to look at whether or not there is shrinkage over time, to look at metabolic activity, energy levels, blood flow, and presence of Alzheimer's plaques in the brain of people who are fairly young. So it's a tricky thing to do, but we have the techniques, we have the technology, we can do that. And then, if you compare the brains of women, middle aged, midlife women and midlife men, very consistently, we have shown time and time again, that the women exhibit signs of an increased risk of Alzheimer's disease in their brains. There's a little bit more shrinkage. The gray matter is losing a little bit of volume. Blood flow to the brain is changing. Brain energy levels are changing, and there are more Alzheimer's plaques. This is not to say that these individuals have dementia or have Alzheimer's disease. These are risk factors for Alzheimer's disease, they're red flags. And we looked at a number of factors. We started with age, and really, we could not find any strong correlation with aging alone. So then we look at genetic risk factors. So if you're premenopausal, you have a regular cycle, you have no hot flashes, no symptoms of menopause, your brain is broadly the same level of energy and activity and structure and whatnot than a man's brain of your same age. But as you start going through menopause, during perimenopause, which is the transitional phase during which we start skipping periods and the hot flashes really make an appearance and the brain fog and the memory lapses and the anxiety or the depression, then your brain starts changing in ways that, sure, there is a bit of an aging component, but I think the hormonal changes are very clear. Because we work with women, who are fairly young when they they go through menopause, and we work with women, who are older as they go through menopause, and it's not their age that predicts their brain health or their brain changes, it's really the stage of menopause that they're at.
Menopause hot flashes may indicate higher risk of Alzheimer’s disease
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Updated: 3:59 PM EDT Oct 9, 2023
Women are about twice as likely to develop Alzheimer’s disease than men.Though we still don’t know specifically why women comprise the majority of cases, previous research has looked at the relationship between menopause and Alzheimer’s, including one study published earlier this year that found early menopause may increase the risk. Now, new research shows how a common menopause symptom, hot flashes, may indicate a higher risk of Alzheimer’s.A study presented at the 2023 Annual Meeting of The Menopause Society in Philadelphia investigated if hot flashes are associated with adverse biomarkers, or signs, of Alzheimer’s disease. This study builds on previous research about the connection between hot flashes and brain health, including one 2022 study that found people who experience hot flashes tend to have more white matter hyperintensities, a brain biomarker that has been linked to an increased risk of Alzheimer’s disease.The new study examined vasomotor symptoms—or hot flashes and night sweats—in 248 people with a uterus and at least one ovary ages 45-67. The participants were either late-perimenopausal or postmenopausal. Researchers found that women who have hot flashes, particularly those that occur during sleep, may have a higher risk for Alzheimer’s. They also found that a greater number of sleep hot flashes was associated with an increased likelihood of Alzheimer’s. “Among other things, these findings indicate that women who experience frequent hot flashes, particularly during sleep, may warrant AD dementia risk reduction efforts,” said lead author Rebecca Thurston, director of women’s biobehavioral health at the University of Pittsburgh Department of Psychiatry, in a press release. These reduction efforts may include preventative lifestyle habits (like following a brain-healthy diet and exercising regularly) and also consulting with your doctor about your risk factors. How are hot flashes linked to Alzheimer’s risk?Hot flashes are a common symptom of menopause, occurring as a result of erratic or diminished estrogen production, says Sheryl A. Ross, M.D., women’s sexual health expert and author of She-ology and She-ology the She-quel. “Hot flashes at night are called night sweats and in this study, this was associated with a low-value biomarker called, amyloid B 42/20, suggestive of a higher risk of Alzheimer’s disease,” she explains.The association of hot flashes during sleep and Alzheimer’s disease may indicate that disruptions in sleep patterns could contribute to Alzheimer’s risk, suggests Anat Sapan, M.D., board-certified ob/gyn and menopause expert. “Alternatively, estrogen has neuroprotective effects, and its decline may affect brain health,” she adds. Research has shown that Alzheimer’s is driven predominantly by reduced brain cell metabolism and increased inflammation, says Dale Bredesen, M.D., neuroscience researcher and neurodegenerative disease expert. “The reduction in estradiol , especially if rapid, represents a reduction in the in the brain, thus hormonal reduction is associated with both hot flashes and Alzheimer’s,” he explains.Why are women at higher risk for Alzheimer's?Although men also develop reduced hormonal support over time—a reduction in testosterone, for example—the decline in hormones for women is a steeper curve, so the drop is more rapid, triggering a reduction in brain cell support that is more severe than typically occurs with men, says Dr. Bredesen. “However, it’s important to note that there are many other triggers for Alzheimer’s, so this is only one factor.” There are many other risk factors, including diabetes, high blood pressure, chronic obstructive pulmonary disease (COPD), older age, sedentary lifestyle, poor sleep, unhealthy diet, and genetic risk factors, that are also associated with an increased risk of Alzheimer’s disease, says Dr. Ross.The bottom lineThis study establishes correlation between the occurrence of hot flashes and increased Alzheimer’s risk, but more longitudinal studies are needed to closely examine the relationship between decreased estrogen levels and risk for Alzheimer’s, says Shae Datta, M.D., co-director, NYU Langone’s Concussion Center, and director of cognitive neurology at NYU Langone Hospital—Long Island. “While correlation is important, it does not always mean that is the ‘cause’ for a disease,” she explains. Still, this study highlighting the possible connection between nighttime hot flashes and Alzheimer’s risk underscores the significance of sleep and estrogen for brain function, says Dr. Sapan. “It is important to recognize this risk as well as the other physical, environmental, and genetic risks of and be proactive.” Menopause hormone therapy can not only help alleviate menopause symptoms but also potentially reduce the risk of Alzheimer’s, adds Dr. Sapan. These results suggest that “all women who are entering perimenopause or menopause should consult their physicians about their risk factors for cognitive decline to discuss the best plan for preventing cognitive decline,” adds Dr. Bredesen.Educating yourself on all the risks associated with Alzheimer’s disease is helpful in learning ways to prevent it, says Dr. Ross. “Eating a colorful and healthy diet similar to the Mediterranean diet, exercising 150 minutes per week, minimizing alcohol intake, not smoking, sleeping seven to eight hours a night, and practicing mindfulness, will reduce your risk of chronic medical problems and your risk of Alzheimer’s disease,” she adds.
Women are about twice as likely to develop Alzheimer’s disease than men.
Though we still don’t know specifically why women comprise the majority of cases, previous research has looked at the relationship between menopause and Alzheimer’s, including one study published earlier this year that found early menopause may increase the risk. Now, new research shows how a common menopause symptom, hot flashes, may indicate a higher risk of Alzheimer’s.
A study presented at the 2023 Annual Meeting of The Menopause Society in Philadelphia investigated if hot flashes are associated with adverse biomarkers, or signs, of Alzheimer’s disease. This study builds on previous research about the connection between hot flashes and brain health, including one 2022 study that found people who experience hot flashes tend to have more white matter hyperintensities, a brain biomarker that has been linked to an increased risk of Alzheimer’s disease.
The new study examined vasomotor symptoms—or hot flashes and night sweats—in 248 people with a uterus and at least one ovary ages 45-67. The participants were either late-perimenopausal or postmenopausal.
Researchers found that women who have hot flashes, particularly those that occur during sleep, may have a higher risk for Alzheimer’s. They also found that a greater number of sleep hot flashes was associated with an increased likelihood of Alzheimer’s.
“Among other things, these findings indicate that women who experience frequent hot flashes, particularly during sleep, may warrant AD [Alzheimer’s disease] dementia risk reduction efforts,” said lead author Rebecca Thurston, director of women’s biobehavioral health at the University of Pittsburgh Department of Psychiatry, in a press release. These reduction efforts may include preventative lifestyle habits (like following a brain-healthy diet and exercising regularly) and also consulting with your doctor about your risk factors.
How are hot flashes linked to Alzheimer’s risk?
Hot flashes are a common symptom of menopause, occurring as a result of erratic or diminished estrogen production, says Sheryl A. Ross, M.D., women’s sexual health expert and author of She-ology and She-ology the She-quel. “Hot flashes at night are called night sweats and in this study, this was associated with a low-value biomarker called, amyloid B 42/20, suggestive of a higher risk of Alzheimer’s disease,” she explains.
The association of hot flashes during sleep and Alzheimer’s disease may indicate that disruptions in sleep patterns could contribute to Alzheimer’s risk, suggests Anat Sapan, M.D., board-certified ob/gyn and menopause expert. “Alternatively, estrogen has neuroprotective effects, and its decline may affect brain health,” she adds.
Research has shown that Alzheimer’s is driven predominantly by reduced brain cell metabolism and increased inflammation, says Dale Bredesen, M.D., neuroscience researcher and neurodegenerative disease expert. “The reduction in estradiol [estrogen], especially if rapid, represents a reduction in the [cell metabolism] in the brain, thus hormonal reduction is associated with both hot flashes and Alzheimer’s,” he explains.
Why are women at higher risk for Alzheimer's?
Although men also develop reduced hormonal support over time—a reduction in testosterone, for example—the decline in hormones for women is a steeper curve, so the drop is more rapid, triggering a reduction in brain cell support that is more severe than typically occurs with men, says Dr. Bredesen. “However, it’s important to note that there are many other triggers for Alzheimer’s, so this is only one factor.”
There are many other risk factors, including diabetes, high blood pressure, chronic obstructive pulmonary disease (COPD), older age, sedentary lifestyle, poor sleep, unhealthy diet, and genetic risk factors, that are also associated with an increased risk of Alzheimer’s disease, says Dr. Ross.
The bottom line
This study establishes correlation between the occurrence of hot flashes and increased Alzheimer’s risk, but more longitudinal studies are needed to closely examine the relationship between decreased estrogen levels and risk for Alzheimer’s, says Shae Datta, M.D., co-director, NYU Langone’s Concussion Center, and director of cognitive neurology at NYU Langone Hospital—Long Island. “While correlation is important, it does not always mean that is the ‘cause’ for a disease,” she explains.
Still, this study highlighting the possible connection between nighttime hot flashes and Alzheimer’s risk underscores the significance of sleep and estrogen for brain function, says Dr. Sapan. “It is important to recognize this risk as well as the other physical, environmental, and genetic risks of [Alzheimer’s] and be proactive.” Menopause hormone therapy can not only help alleviate menopause symptoms but also potentially reduce the risk of Alzheimer’s, adds Dr. Sapan.
These results suggest that “all women who are entering perimenopause or menopause should consult their physicians about their risk factors for cognitive decline to discuss the best plan for preventing cognitive decline,” adds Dr. Bredesen.
Educating yourself on all the risks associated with Alzheimer’s disease is helpful in learning ways to prevent it, says Dr. Ross. “Eating a colorful and healthy diet similar to the Mediterranean diet, exercising 150 minutes per week, minimizing alcohol intake, not smoking, sleeping seven to eight hours a night, and practicing mindfulness, will reduce your risk of chronic medical problems and your risk of Alzheimer’s disease,” she adds.
