Question: what percent of 80 year olds have dementia?
Answer: Research has shown that dementia prevalence for both men and women increases from age 65 to 85. The frequency of dementia increases with age from less than 2 percent for the 65-69-year-olds, to 5 percent for the 75-79-year-olds and to more than 20 percent for the 85-89-year-olds.