Sir: Ageism can work the other way, too. I am 67 and have an arthritic knee which my NHS consultant tells me will need to be replaced at some time in the future - "but we don't like doing this until the 70s". The rationale behind this is that a replacement knee is expected to last about 15 years and a second replacement is not usually very successful.
Both my parents and both my grandmothers, as well as sundry aunts and uncles, have lived to be 90-96. I therefore expect to live well into my mid-90s. Will I have to wait until I am nearly 80 before I have my knee operation?