Sudden loss of short term memory?

[1stWorldProblems]

Apologies - a long explanation - but they so often are these days.
87 year old MIL lives 500 yards from our house & has been walking up to have supper with us every night for the last 3 years. Two weeks ago she got lost on the journey! I had seen her earlier in the day & she seemed her usual cheerful self, slightly vague but no more than that but that night she seemed like a different person - suddenly old & confused. Two days later she had a nasty fall & forgot to press her 'fall bracelet' so was on the floor for at least 12-hours - resulting in a pressure sore & admittance to hospital.

They did a CT scan but didn't find any signs of a stroke. She was given intravenous antibiotics and fluids and seemed back to normal after a week - so initially we thought the mental issues were due to a UTI or dehydration. BUT she's now been out of the hospital for a week and her short-term memory is still a lot worse than a fortnight ago - for instance she had the nurse come today to dress a cellulitis wound on her leg. She is currently in a local care home - in theory for a month of respite care after her fall but it's looking increasingly like she won't be safe to go back to her flat even with full-time carers.

So my question is - can dementia suddenly accelerate like this? All my other (blood) relatives who developed dementia did so in a slow decline - whereas she has gone from being relatively independent - feeding herself breakfast & lunch, getting herself to medical appointments, etc. to not knowing what day it is or who's been to visit her or if she's eaten in a fortnight. Thanks

Unfortunatly dementia can progress in jumps, especially the vascular type. My mum had fronto temporal dementia and she would have massive downturns, especially if she got a UTI or other infection, or an anaesthetic. With the medical induced ones she would regain a bit when that was resolved but never back to before.

Sadly yes, vascular dementia often has a pattern of sudden drops is capacity, followed by periods of stability. It can be a result of mini-strokes. Not sure if they would show up on CT.

An episode of delirium brought on by a UTI can also be a tipping point.

I’m sorry OP these sudden downturns are really distressing. It does sound like something happened that couple of days before that triggered a decline, and then the fall

Op, check out Delerium. this is very common in the elderly and causes a sudden change in cognition.
if it were my mum I would get her to GP ( or A and E if you can’t get GP appointment pronto/within 24 hours ) - a blood test will tell whether her inflammatory markers are up. If they are , then it’s a case of finding out why ( infection, allergy to antibiotics etc) and sorting it out.

Delerium is classed as a medical emergency. Not because it’s life threatening but because it’s a sign that something is wrong and the longer it goes on, the longer it will take to resolve.

Take heart though - if it is delerium, your Mum will likely get back close to where she was before once the cause has been treated.

My dads fronto temporal lobe dementia went in quite marked steps downward- we'd just make adjustments for what he could(n't) do and he'd take another big step downwards-