Differences between Rheumatoid Arthritis and Osteoarthritis

May is Arthritis Awareness month and RheumatoidArthritis.Net is joining in the recognition. “Arthritis” is a general term and, according to the American College of Rheumatology, is used for over 100 diseases.¹ Arthritis simply refers to inflammation of a joint.²Osteoarthritis (OA) is more common with age and is typically considered non-inflammatory – associated with wear and tear on joints.³ Inflammatory forms of arthritis tend to be caused by an autoimmune response – the body attacking itself. Common forms of autoimmune inflammatory arthritis include rheumatoid arthritis (RA), ankylosing spondylitis, and psoriatic arthritis.⁴ Inflammatory arthritis can impact people of all ages.

It is true that inflammatory cytokines like tumor necrosis factor (TNF) and interleukin 6 (IL-6) are found in the joints of OA patients.⁵ But having increased levels of these cytokines localized in a joint is vastly different than increased levels coursing throughout the body. These cytokines are present in many systemic inflammatory diseases including Crohn’s Disease, psoriasis, and rheumatoid arthritis.

The systemic and autoimmune nature of rheumatoid arthritis is what separates it from the more common osteoarthritis. As outlined in an earlier post, RA can impact more than just bones including lungs, heart, eyes, nerves, and blood vessels. While OA impacts tens of millions of Americans, and the financial impact of OA is staggering, RA can be much more devastating in terms in individual impact over a lifetime including unemployment, disability, and early death.^6,7

There has been discussion about whether to call it rheumatoid arthritis (RA) or rheumatoid disease (RD).⁸ There is good reason behind such an argument in that RA is vastly different from OA because of the systemic nature of RA with it’s potential impact on many parts of the body. Given the long term use of the term RA by doctors, professional societies (e.g., American College of Rheumatology), researchers, and society as a whole, implementing such a change would be a monumental challenge.

The next time someone says that they have RA in their pinky finger or that you’re too old for RA, attempt to clear up their confusing RA with OA by letting them know that there’s a big difference. You can start by referring them to the “What is RA” page on this site.