Nearly two-thirds of Americans with Alzheimer’s disease are women, and now some scientists are questioning the long-held assumption that it’s just because they tend to live longer than men.
What else may put woman at extra risk? Could it be genetics? Biological differences in how women age? Maybe even lifestyle factors?
Finding out might affect treatments or preventive care.
One worrisome hint is that research shows a notorious Alzheimer’s-related gene has a bigger impact on women than men.
“There are enough biological questions pointing to increased risk in women that we need to delve into that and find out why,” said Maria Carrillo, chief science officer for the Alzheimer's Association.
Last month, the association brought 15 leading scientists together to ask what’s known about women’s risk. Later this summer, Carrillo said it plans to begin funding research to address some of the gaps.
“There is a lot that is not understood and not known. It’s time we did something about it,” she added.
A recent Alzheimer's Association report estimates that at age 65, women have about a 1 in 6 chance of developing Alzheimer’s during the rest of their lives, compared with a 1 in 11 chance for men.
The tricky part is determining how much of the disparity is due to women’s longevity or other factors.
“It is true that age is the greatest risk factor for developing Alzheimer’s disease,” said University of Southern California professor Roberta Diaz Brinton, who presented data on gender differences at a meeting of the National Institutes of Health this year.
But, she said, “on average, women live four or five years longer than men, and we know that Alzheimer’s is a disease that starts 20 years before the diagnosis.” That’s how early cellular damage can quietly begin.
Brinton researches if menopause can be a tipping point that leaves certain women vulnerable.
