Old person somehow beginning to improve, right after avoiding hospital care (9)

I believe the answer is:

geriatric

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'old' is the definition.
(I've seen this before)

I don't understand how the rest of the clue works.

(Other definitions for geriatric that I've seen before include "Relating to old people" , "Oldie" , "treatment of the elderly" , "past it" .)

I've seen this clue in The Telegraph.

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