June is Alzheimer's Awareness Month. Though the disease is exceedingly complex and scientists are still investigating the causes of Alzheimer’s, it is known as the most common form of dementia and is heavily associated with memory loss. According to the Centers for Disease Control and Prevention, 5.8 million Americans were living with the disease in 2020. Unless treatment measures are determined, the amount of Americans living with Alzheimer’s is projected to nearly triple to 14 million people by 2060. While age appears to be the highest risk factor for the disease, gender seems to play a fundamental role in Alzheimer’s development and diagnosis as well. In fact, 70% of Alzheimer’s sufferers are women. Researchers are still actively investigating why women are so disproportionately affected, but there are three key hypotheses that begin to unpack the issue:
1. Women live longer.
While this hypothesized reason is the most directly related to age, which experts maintain as the main risk factor for Alzheimer’s, many argue that this isn’t enough to explain such a drastic increase in impact. On average, women live four and half years longer than men. Every five years after the age of 65, the risk of receiving an Alzheimer’s diagnosis doubles. Because women live longer, our brains have more time to be susceptible to disease, increasing the risk of cognitive decline. With that said, even from a statistical perspective, this reasoning doesn’t consider any specific mechanism or account for the drastic difference.
2. Women experience more radical hormone shifts in aging, namely the onset of menopause.
Experts estimate that Alzheimer’s is formally diagnosed approximately 20 years after the onset of symptoms. Given that the average age of Alzheimer’s diagnosis is 72–75 years old, 20 years before that leads to a notable hormonal shift in women– menopause. Though we often associate estrogen with sexual and reproductive regulation, recent studies indicate that it also serves as a neuroprotective hormone. This means that estrogen levels help facilitate many of the signals necessary for healthy brain activity, streamlining communication and preventing decay. So when estrogen levels drop at the onset of menopause, an important layer of protection is lost, making regulatory connections more vulnerable.
3. Women’s brains are more likely to remain in modes of chronic stress.
This is not to say that men and women don't both endure chronic stress. Rather, the duration of a stress response is longer in women’s brains. This makes sense given that women’s hormone regulatory schedules are longer and more complex than men’s. Since men’s hormone resets happen within shorter windows of time, the chronic stress state recedes more quickly. Because these hormonal resets don’t happen as often in women’s brains, this means that we remain in the fight-or-flight response mode for longer. This in turn damages the hippocampus, an area of the brain that is essential for memory. The longer the stress response, the more potential damage to the hippocampus, and the greater the risk for memory loss and the onset of Alzheimer’s.
So, this Alzheimer's Awareness Month, let's be cognizant of the role that this disease continues to play in our society. Let's be aware of how it shapes everyone, while also particularly knowing that we as women need to be especially intentional about maintaining our brain health. For more information about Alzheimer's and women’s brain health at-large, here are some resources:
