A review regarding the findings of the 90+ Study in the United States, the biggest study on dementia and other health factors in the country, found recently that women with ages over 90 years are more likely to have dementia than men. The original study involved the investigation of 911 people with ages over 90 and indicated, according to University of California researchers, that almost half of the women participating in the study had some form of dementia, as opposed to 28 percent of men.

The US has the fastest-growing age demographic, with almost 2 million people of its total population being over 90 years of age. Predictions indicated that the number could grow up to 12 million by 2050, which is already raising concerns within the country’s health care system, which may collapse under the pressure of such a big number.

"Our findings show that more will need to be done to provide adequate resources to care for the increasing number of very old people with dementia," said Maria Corrada, a University of California epidemiologist.

The 90+ Study revealed that the rate of dementia occurrence grows with age, regardless of gender, from 2 percent between 65 and 85 years of age to more than 20 percent amongst people between 85 and 89 years old. The original study however did not include any reference to people over 90, an assignment picked up by the University of California. Their findings indicate that for every five years the risk of developing dementia doubles in women with ages exceeding 90, and more than half of the women that had some form of dementia received less education.

Currently, women make up for three-quarters of the nonagenarian population of the US, 45 percent of which are predisposed to dementia, albeit the review was unable to establish why women are more likely to develop such a progressive brain dysfunction.

"Our findings provide valuable information toward further inquiries into dementia, such as if oldest-old men can live as long with dementia as oldest-old women do, or whether in this age group women develop dementia at a higher rate than men," Corrada said.