All I can advise you on the differences between them are easily found with online searches. As mentioned in another reply, the rate of decline tends to be more slow and steady with AD.

Be very aware that sometimes a simple “cold” or a virus or a UTI ( which become more common as the person isn’t showering themselves any more and may end up with adult diapers) all of these can suddenly cause a huge change in behavior and routines.

You will need to prepare for times you are away that someone will be getting her to a doctor appointment, do bloodwork or get urine samples done and tested. It’s not just care that is done at home. When the changes come the doctors will want to have some documentation and observations from the main caregiver in order to consider recommendations.