Women over age 90 are significantly more likely to have dementia compared to men in their 90s, according to a study published in the July 2, 2008, online issue of Neurology, the medical journal of the American Academy of Neurology.
Research shows that dementia risk for both men and women increases from age 65 to 85, but this most recent study is one of few that looks at people over age 90.
"While men don't typically live as long as women, those who do make it to age 90 appear to be much less likely to have dementia and also have a shorter survival time when they do have dementia," according to study author Maria Corrada, ScD, with the University of California, Irvine.
Researchers reviewed an analysis of about 900 people age 90 and older. Of those, 375 had dementia.
The study found that women were nearly twice as likely to have dementia in their 90s compared to men. The results also showed that the likelihood of having dementia doubled every five years in women but not in men.
"As more and more people reach age 90, our findings provide further evidence that more needs to be done to provide adequate resources to care for the increasing number of very old people with memory problems," said Corrada.
In addition, the study found that women with a higher education appeared to be as much as 45 percent less likely to have dementia compared to women with less education.
The 90 plus age group, or the "oldest-old" is the fastest growing segment of the elderly population according to the US Census.