I'm almost 14 years out - I'm on 5mg per day... I think that, initially, prednisone was the primary drug that caused/aggravated my post-transplant diabetes, though the Prograf certainly added to the problem. Back when I was transplanted - they didn't jump all over our blood-glucose swings as quickly as they do now - they tended to watch them longer... Now, they better understand the problems that high blood-glucose causes...
About 10 weeks post transplant - I was diagnosed diabetic. At that time, they ramped my prednisone down from 10mg to 5mg - possibly a few months before they would have done so, and because of the diabetes situation...
I've stayed on 5mg ever since - we bounced it up a bit, for 3-4-5 weeks, after I had my kidney transplant, 12 years post lung transplant... And I'm back to 5mg again. Love, Steve