I'm sure that is always so. I'm someone with type 2 diabetes who is going blind and I can assure you my doctors of various kinds tell me where to go for low-vision clinics and all kinds of other things, and what foods to eat and not eat. There are supports out there. With regard to the example you used, these people who get insulin have medical consultants.
On January 28th, 2016. See this statement in context.