[wpietri]

Which reminds me, I should mention that for anybody with an elderly relative who experiences a sudden decline in the direction of delirium or dementia: make sure they don't have a urinary tract infection.

I have no idea how that plumbing is connected, but I have seen it happen myself, and apparently it's a not-uncommon experience for people with Alzheimer's: https://www.alzheimers.net/2014-04-03/connection-between-uti...

And yes, it is entirely freaky when somebody you have known for years starts talking utter gibberish and clearly expects to be understood. It feels deeply unreal.

[dcminter]

Or indeed other infections. As it was explained to me, elderly people sometimes can't get a fever so the first sign something is wrong can be confusion and other odd behaviour.

In the case of my late mother, it manifested as a fixation on and paranoia about money.

Definitely one to bear in mind.

[copperx]

Talking gibberish is also one of the first symptoms of stroke, but that's well-known.