I'm so sorry to hear about your father. Exercise and things like reading, puzzles, and word finds can help the speed of progression of this dementia. My dad never because argumentative or disagreeable but he began hallucinating and seeing things and people who weren't there during the later stages.

There's a specific gene you can be tested for to find out your own risk...it's the e4 variant in the APOE gene. If this e4 variant is present in your DNA your risk is greater (but that doesn't mean you'll develop dementia). There's so much they don't yet understand about it. Concussions/head trauma also increase a person's risk. Companies like 23andMe and other genetics companies can test for this if you want to know.