I think each person is different. My moms was gradual at the beginning but has definitely increased and happens quicker. If it is a sudden change to their normal confusion can be a sign of a UTI. Also with my mom when she has gotten sick or something has accelerated her progression she typically does not bounce back to her baseline preillness/injury.
My Daughters and I notice small changes in hubby daily but he's still undiagnosed😢💔
His happened gradually. Our daughter lives in another state but this year has visited twice and is planning another. She says she sees changes each time. Changes I don’t realize because i’m Too busy dealing with the daily stuff.