I have a theory, and it is perhaps rather sexist and Non PC, but perhaps in keeping with the male / female role models of the elderly generation today.
BTW, both men and females in my family have the sliding scale between parkinson and levii body dementia - my mum the latter.
One thing is that women die later, and men are more prone to dying from other illnesses, like heart disease or stroke, but I think more women than men get diagnosed and here is why:
What did many men traditionally do after work? They relaxed. They got served dinner, they put their feet up, watched tv, saw their mates, perhaps cleaned the car or mow the lawn, eventually got to bed. Women did the housework and the caring. If an elderly man retired, and ended up with poor memory, snoozing in his chair in front of the tv, the wife would just put up and shut up and cater to his needs.
If the WIFE on the other hand, started making a mess of dinner, make a mess of housework, and shopping and putting shopping away, made a mess of caring for grandkids, her husband would most definitely notice and find it odd, and most likely not stand for it. He would push her to a doctor, in a larger degree than a wife with a man snoozing in a chair would.
But think about the gender roles with your grandparents and elderly parents and what they do at home after work, and what they do when they retire, which person would be most likely to mess up?
My dad could spend hours in his armchair watching tv, while my mum faffed about. When she first got her diagnozis it was because she started forgetting how to cook and how to bake. She was already retired, as was my dad. I think in most traditional households a housewifes duties stay the same after retirement while men start chilling. (my mum worked part time and retired age 67, got her diagnosis at 71)