At first I thought this was my note, but the numbers are different. I was put on 60 mg of prednisone and not down to 10mg. I read the what triggers PRM is unknown, but heredity appears to play a role. If that is the case, I got it from my mother. She has had it for a few years. It also just came on her, with all her other "old age" aches and pains. Hope this helps.