Question: How do symptoms differ when comparing osteoarthritis and rheumatoid arthritis?
Answer: Rheumatoid arthritis is a systemic inflammatory disease. By this, we mean that there's inflammation throughout the whole body. And the problem is not just in the joints. At the same time, what happens in the joints is also inflammatory. And that's very different from the situation in osteoarthritis which is a degenerative sort of arthritis. In osteoarthritis, the cartilage that lines the joints begins to wear out. As the cartilage wears, you begin to get bone spurs and changes in the bone around that joint that limit the function and also increase pain in that joint. But that's all the condition of wear-and-tear basically.
In rheumatoid arthritis what happens is inflammation in the tissues that surround and line that joint causes that kind of damage, and that inflammation itself can cause stiffness, can cause pain, can cause swelling, can cause fluid within the joint. People with rheumatoid arthritis because of that inflammation have much more stiffness in their joints than somebody with osteoarthritis. So it would be very typical for a rheumatoid arthritis patient to get up and tell you that they have stiffness lasting two or more hours in the morning before their joints loosen up, before they can really begin their day. In osteoarthritis on the other hand, it would be very rare to have stiffness lasting more than perhaps 15 or 20 minutes, maybe even a half an hour in the morning. There just isn't the inflammation that causes that.
There are other manifestations of rheumatoid arthritis that we don't see in osteoarthritis. So in osteoarthritis the process is limited to the joints -- it's a degenerative condition of the joints. There's no impact on the rest of the body other than what happens around the joints that are involved. In rheumatoid arthritis, the systemic nature of the disease causes inflammation that can create fatigue, can cause weakness, can cause anemia and other sorts of things that make the patients feel ill beyond just what's going on in their joint. One of the signals for this is a rheumatoid nodule which is a collection of inflammatory tissue or inflammatory cells that may appear at places distant from a joint on a tendon or someplace else that's not specifically in the joint.
Finally one of the things we've learned recently that's of critical importance is that the systemic nature of rheumatoid arthritis -- the inflammation that involves the whole body -- has very important implications for the health of people with rheumatoid arthritis. And we've learned that that inflammatory actually drives a lot of cardiovascular disease. So patients with rheumatoid arthritis have a much higher risk for having heart disease, for having heart attacks, for having strokes than people who don't have rheumatoid arthritis, and aggressive treatment of the arthritis can actually reduce those risks. It turns out that people with rheumatoid arthritis, much of the reason they end up hospitalized, much of the reason they die is typically not the arthritis, but the cardiovascular disease that is associated with it. And that's very different from osteoarthritis where the problem is just in the joints. So the systemic nature of rheumatoid arthritis causes other symptoms and it's increasingly being recognized as something we have to pay a lot of attention to because it has really strong implications for the health of the patient in general.