Women in their 90s are significantly more likely to suffer from dementia than men of the same age, say US researchers.
A study of more than 900 people aged 90 or over – one of the largest studies on dementia in this age group - found that 45% of the women had dementia compared to just 28% of the men.
Previous research has shown that the prevalence of dementia for both men and women increases with age, from less than 2% for 65-69 year-olds to more than 20% in 85-89 year-olds.
However, the researchers found that in women over 90 the likelihood of having dementia doubled every five years, but not in men.
Women with lower levels of education were also significantly more likely to have dementia than those who had received higher education, the authors said online in the journal Neurology.
Study author Maria Corrada, epidemiologist at the University of California, said: ‘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.’