Thanks for all the info.
I have had an elevated blood sugar count for some time, kept under control by diet, but I understand that there may be some links.
I worked possibly the worst combination of shifts for most of the last 35 years ( Afternoon, Day, Morning - followed by night on the same day, or Day the following day - then two days off) and presumably this did not help. I've been home for a couple of weeks now so am still adjusting to the regularity.
Anyway, off to the docs. on Friday.