It's a startling number. Every 65 seconds in the U.S., someone develops Alzheimer's disease.
According to new research, there's a biological reason why women are more likely to get the disease.
Harry and Bettie Dunn love to reminisce about their past adventures during their 70 years of marriage.
"I know as you grow older you begin to lose some memory, but I noticed she was losing it more than I was," Harry said.
Harry believes it progressed more rapidly after a bad fall that broke Bettie's hip.
"She really doesn't know people that we've been friends with, sometimes she doesn't know her own children," he said.
"Two-thirds of Alzheimer's patients here in the U.S. are women," said Dr. Sepi Shokouhi, assistant professor of psychiatric and behavioral sciences at Vanderbilt University Medical Center.
Researchers examined 400 brain scans of elderly patients to figure out why the risk for Alzheimer's is higher for women than it is for men. They believe it may have something to do with an abnormal protein in the brain, named tau, which is linked to cognitive impairment.
"These abnormal proteins can spread like infection in the brain," Shokouhi said.
In the study, they found the tau accumulation was more widespread in women's brains than men's, easily moving from one part of the brain to another.
Previous theories on why more women got Alzheimer's disease than men pointed to the fact that women had a longer life expectancy. However, this research also points to a biological reason.
"I can predict that sex will be more strongly integrated in future precision medicine in Alzheimer's disease," Shokouhi said.
The new findings will help to identify therapies that would work best for women.
A study out of University of California at Los Angeles also points to social sex differences when it comes to Alzheimer's disease. They found the rate of memory decline was faster among married women who did not work in the labor force compared to married mothers who did.
Other researchers are studying possible causes like estrogen and one copy of a certain gene.
ALZHEIMER'S ATTACKS MORE WOMEN THAN MEN
BACKGROUND: Nearly 500,000 new cases of Alzheimer's disease will be diagnosed this year in the United States, and every 3 seconds, someone in the world develops dementia. Alzheimer's is the sixth-leading cause of death across all ages in the United States with a 5% increase in number of deaths in the from 2015 to 2016. For those 65 and older, it is the fifth-leading cause of death. Alzheimer's is an irreversible degeneration of the brain that causes disruptions in memory, cognition, personality, and other functions that eventually lead to death from complete brain failure. Caring for a person with Alzheimer's or another dementia is often extremely difficult, and many family and other unpaid caregivers experience high levels of emotional stress and depression as a result. (Source: https://www.brightfocus.org/alzheimers/article/alzheimers-disease-facts-figures)
ALZHEIMER AND GENDER: At the age of 65, women have a 1 in 5 chance of developing Alzheimer's, compared to a 1 in 11 chance for men. And, women in their 60's are twice as likely to develop Alzheimer's than to develop breast cancer. The Alzheimer's Association brought 15 of the world's leading scientists together to look further into why Alzheimer's is more likely in women, stating that "researchers are now questioning whether the risk of Alzheimer's could actually be higher for women at any given age due to biological or genetic variations or differences in life experiences." Genetic studies have offered a surprising account for the difference. Researchers from Stanford University studied over 8,000 people looking for a form of the gene ApoE-4, which increases the risk of Alzheimer's. They found that women who carry one copy of that gene variant were twice as likely to develop the disease as women without the gene. It is not clear why the gene poses such a drastic increase in risk but may be how the gene interacts with estrogen. (Source: https://www.alzheimers.net/8-12-15-why-is-alzheimers-more-likely-in-women/)
HOPEFUL BREAKTHROUGH: A study of more than 11,000 patients found that technology can detect biological evidence of brain changes clearly linked to Alzheimer's. The study involved people enrolled by nearly 1,000 dementia specialists across the country, and all had been diagnosed with either mildly impaired thinking skills or dementia in the last 2 years. "As in any other field of medicine, a clinical history and a physical exam is very important but being able to directly visualize the biology of the organ involved in the disease process is really essential to make an accurate diagnose," says lead study author Gil Rabinovici, MD, a professor at the University of California, San Francisco's Memory and Aging Center. This study used amyloid positron emission tomography, or PET scans, to detect amyloid plaques in the brain, which all people with Alzheimer's have. Before study participants were scanned, Alzheimer's disease was the leading cause suspected for cognitive impairment in 76.9% of patients, while the PET scans read as positive only for Alzheimer's in 55.3% of patients with mildly impaired thinking skills, and 70.1% of those with dementia. "Our hope is when we complete the second phase of the study, we will be able to show the scan not only changes management but improves outcomes, and that will lead Medicare to reconsider covering scans at least in some situations," Rabinovici says. (Source: https://www.webmd.com/alzheimers/news/20190501/alzheimers-diagnosis-breakthrough-hopeful-expensive)