What are the chances that someone would actually doing the hacking? I don't see any monetary reason to do so. Maybe that's one reason why we haven't seen many reports of people hacking medical devices?
Every few weeks / months Bob needs to see a doctor w o enters a password, retrieves the data, and makes changes to the settings.
Bob feels that the $DISEASE community can help him interpret the data and tweak the settings and Bob could then reduce doctor visits to once every six months.
Ann is an undisclosed drug addict and wishes to hack her morphine pump to supply more than she is currently getting.
Etc