The life expectancy of Japanese in 2015 was released as 80.09 year old for
lengthening so much during several decades. I have many patients over 90 year old in my hospital. I thought they were especially long life, so they had dementia. But now 87 is average(female) and near to 90 year old. It is not special to over 90 year. Almost patients near 90 or over have dementia. Although we are able to live near 90(female) or 80 year old(male) now, we must not to become dementia even though to live old age.