My mom all of a sudden goes to "Pee" almost every hour to hour and a half. Can anyone explain this change?

Sudden uncontrollable urges to go pee are also signs of Vascular Dementia.

I agree with the others.. that sudden urge followed by usually a dribble of urine usually signs of UTI or bladder infection. With the elderly it can get worse very quickly... I agree with the consensus !!! Wonderful job catching it early .. our last three my mom seemed to be asymptomatic and ended up being diagnosed in ER only after sepsis took over .  

My first thought was urinary tract infection. Feeling the very frequent urge to go and then there's little urine output much of the time. There can also be visible blood present in the urine

Does she do this every day? Does she actually “go” or is there just the urge? I would have her tested for a bladder infection. This is a simple urine test that can be done in the doctor’s office. This can cause someone to feel like they have to go constantly. As it gets worse, it can also cause some pretty off the wall behavior. If it’s not an infection, there are medications she can take for an overactive bladder. Finally, if she has dementia it could be an obsessive behavior. Those are common in people with dementia.