I had some severe memory issues after COVID, and have had to do "brain exercises" to get my mind back together.
But other mental and physical issues remain.
One thing I'd keep in mind is to consider having your rights of autonomy taken away in the future…I'd definitely plan in advance for things, while still lucid.
(I'm about a decade younger than you, and that would all be a concern for me also, if I didn't plan on leaving soon.)