DEMENTIA-FREE LIFE EXPECTANCY AMONG ELDERLY JAPANESE

A 3-year prospective cohort study was conducted to estimate the life e xpectancy free of dementia (dementia-free life expectancy) in a repres entative sample of older persons living in an urban Japanese community . For the persons aged 65 years and older, who were not demented at ?h e baseline survey in 1988, mortality and incidence rates of dementia w ere calculated, At the age of 65 years, males showed a total life expe ctancy of 18 years, including 16 years free of dementia, and females s howed a total life expectancy of 23 years, including 18 years without dementia, At 65 years, the dementia-free life expectancy represented 8 9% of the total life expectancy for males and 79% for females-Total li fe expectancy and dementia-fi-ee life expectancy were longer among fem ales than among males. However, the life-years with dementia were long er among females, This result would be attributable to a higher incide nce of dementia and a lower mortality among females.