I've my doubts about this.
Our local NHS issues a leaflet about driving and diabetes and there is no mention about hospital treatment for hypos resulting in withdrawal of a licence. From comments I've read about other peoples contacts with DVLA it seems that DVLA are not particularly good at interpreting diabetic conditions or ability to drive even if folk submit GP's or Consultant's opinions.
If the DVLA site doesn't say anything about hospital admission then I wouldn't worry.
Here's a link to the leaflet my GP gave me when I asked if I should inform the DVLA about my diabetes and the fact that I was taking a medication that might cause a hypo. She said that since I'd only ever had one (under unusual circumstances) and my BG was under good control there was no reason to inform DVLA.
http://www.bedfordshirediabetes.org.uk/downloads/Updates 2014/Driving_leaflet-v3[1].pdf
Dave
Edit - I hadn't spotted that you are being treated with insulin so my comments are redundant as per
@himtoo 's post below.
Sorry for any confusion :-(