Mom has bv frontotemporal dementia, gets btw. 3-6 utis a yr. because of poor hygiene practice. how will this affect her kidneys and overall health?

It's not good: This can certainly be difficult and can get worse. Discuss her needs w/ her doctor(s) and slowly prepare for care decisions. Her need for more complete care might become urgent as time passes and planning can help. A problem w/ UTIs is that they plus the antibiotics can both cause problems for the brain and tat can worsen the dementia, etc. It's a vicious cycle and help will help. Best wishes!