This has nothing to do with Adobe or Acrobat/Reader. It is the OS that either supports a bluetooth keyboard or not.
The keyboard is supported by the OS (iOS 10.3.2), and it works well with other programs, but the page up/down functionality (or up,dn,left,right arrow functionality) for turning the pages within the updated Adobe Acrobat iPad app isn't working. Trying to figure out a quick page turn option without having to swipe left/right or up/down on the screen. So, to summarize, it has everything to do with the Adobe app (the only one in which functionality of those keys isn't recognized).
[Moved by moderator from Acrobat Reader to Acrobat Reader for iPhone and iPad now that this reply specifies the issue is actually with Acrobat on the iPad.]
I’m having the same issue viewing PDFs in Dropbox and Acrobat reader. No way to scroll/turn pages from my Apple BT keyboard. Very frustrating.