I think they are two separate disease my husband had Parkinson's about s year and s half before his dementia diagnosis I have also known people to have Parkinson's and never have dementia

There is a dementia that goes along with Parkinsons called Louie Body Dementia

my husband was actually diagnosed with parkingsons about to years prior to the altzhiemers diaganoses

Bless your heart and hers!

So does he have dementia from Alzheimers or is his dementia from Parkinson's? I'm confused.