Just came back from walking the dogs, and it occurred to me that I should mention, especially for Graham's benefit, that DHEA could quite possibly help his PMR or at least allow him to greatly reduce prednisone. I don't know if it's available where he is, as it isn't legal in Canada, but is readily available on drug store shelves in the US.
DHEA could possibly (not proven) contribute to hormone sensitive cancers, especially breast cancer, so I stopped taking it, but for the few months I was on it, I was able to reduce my prednisone significantly (from 10 mg to 4 mg.), then when I went off it due to concerns about breast cancer (my mom died of it) I ended up having to boost my prednisone again.
Many lupus sufferers (another auto immune disease) are able to go off prednisone by taking DHEA. I'd go back on it again in a heartbeat if it weren't for the cancer worry (at least PMR isn't fatal!).