I have been researching clinical studies on RA and FM, since I now have both. I found that the scientific / medical community classify a person with both as a RAF. However, googling it just brings up the Red army Airforce and doesn't help at all. Here is an example from a study...
Fibromyalgia (FM) is a controversial construct. Recently suggested survey criteria identify persons with FM characteristics without physical examination or clinical diagnosis, thereby obviating many of the objections to FM. Little is known about FM among patients with rheumatoid arthritis (RAF).
See, it is a secret acronym I guess.
Chronic widespread pain, the hallmark of FM, is prevalent among elderly women in the general population and appears to predict progression of disability2, and persons fulfilling FM criteria show impaired functioning and quality of life3. Moreover, Wolfe and Michaud4 have reported that patients with RA and FM (RAF) have more severe RA by both subjective and objective measures, worse outcomes, and lower quality of life compared to other RA patients http://jrheum.com/subscribers/09/01/9.html
I am searching for info on this combined disease RAF because sometimes, when I am in pain, I don't know which one is affecting me the worse. The flairs are similar but the relief is not.
Healthcentral.com states that the two pains are very distinctive - " It's two completely different kinds of pain, but they can be similar in intensity. RA pain feels more internal, a bone grinding deep ache, whereas fibro pain feels more like your body is having hysterics."
"RA pain can be eased by staying still - you don't want to do that too much, though, or you may lose mobility - but if you stay still with fibromyalgia pain, your body seizes up more and the pain intensifies. Another important coping tool is to stay warm and that works for both RA and fibro. However, it's even more important for fibromyalgia because if you get cold, fibro goes nuts and it can take days to get ahead of the pain again"
I have both and my RA does not always affect my joints... my hands swell and I can barely move them they ache so bad - but its not in the joints and it is RA. My RA affects my muscles due to the intense inflammation going on. This is not related to the FM but when they both flair who is to know the difference. I am still researching and will keep it posted