Treatment and Response Assessment in Spondyloarthritis
JUNE 15, 2016
MD Magazine Staff
John D. Reveille, MD, and Philip J. Mease, MD, discuss the historical perspective and standard of care in ankylosing spondylitis and how to assess response in psoriatic arthritis.
John D. Reveille, MD: As far as treatment is concerned, all we really had to offer these patients for so many years was nonsteroidal anti-inflammatory drugs. First aspirin, and then in the 1950s and 60s, drugs such as indomethacin and phenylbutazone came around, and then in the ‘70s and 80s, all the other nonsteroidals came out. In the early 1990s, we began to recognize that sulfasalazine was useful, and this was used especially, in peripheral spondylitis. It didn’t work so well for axial spondylitis or ankylosing spondylitis where the problem was in the spine, but in the peripheral joints it worked very well.
And then in about 2000, it became recognized that a new class of drugs called the TNF (tumor necrosis factor) blockers were also very effective in treating this disease. And so from 2000 onward, we’ve been using TNF blockers. And they’ve really helped a great deal to control some of the devastating features of ankylosing spondylitis, as well as axial spondyloarthritis. Only recently have other classes of drugs come to the forefront that are also showing great promise.
The current standard of care for the disease is, first of all, making an accurate diagnosis. B27 test alone isn’t enough. They also have to have positive imaging, either by standard X-rays in the case of ankylosing spondylitis or by MRI for non-radiographic axial spondyloarthritis. Once the diagnosis is made, the patient needs some education, what things to avoid or not to avoid. For example, tell a person just starting out in their professional lives to avoid a blue-collar job because we’ve shown that they tend to do worse, and more likely end up on disability. A white-collar job is preferable in that setting. We advocate an exercise program—at least a half hour a day, 5 days a week—that is very effective in not only maintaining functionality, but even decreasing pain. And then, we will start with nonsteroidals. Again, 50% can be controlled with that regimen alone. You want to take full anti-inflammatory doses. For the other 50% that don’t respond, usually if you’ve tried two different NSAIDs over a 6-week to 3-month period, we then will recommend—if in the case of persistent axial disease—a biologic agent, such as an anti-TNF blocker. The doses are a little different than we use with rheumatoid arthritis, but, again, that will control the majority of the rest of the patients.
Philip J. Mease, MD: Psoriatic arthritis is a very heterogeneous disease with many clinical domains that may be present in a patient. And so it’s important to measure not only arthritis—as you typically would a rheumatoid arthritis patient with assessment—and a number of tender and swollen joints, but it’s important to also measure or assess enthesitis, dactylitis, spondylitis, and skin and nail disease at least as a rheumatologist—a gestalt about the skin and nails, even though the dermatologist is going to be more precisely assessing that particular area.
It’s also important to assess the patient’s joints totally. In rheumatoid arthritis, we can do a 28-joint count, and that’s enough. But, in psoriatic arthritis, oftentimes inflamed joints may be in the feet and ankles, and so it’s important when evaluating the patients to have them take their shoes off and actually assess the toes and the ankles.
In addition, we encourage you to develop some approach to assessing enthesitis. For example, pressing on the Achilles’ tendon insertion of the planter fascia insertion—where the inferior and superior tendon attaches to the patella—to assess for the presence of enthesitis. Look at the fingers and toes to see if dactylitis was present. The reason for that is that both dactylitis and enthesitis’ presence is a marker of more severe disease activity. And so you want to know if they’re present because it may change your strategy about treatment.
So, what we do is we assess all of these domains, and particularly taking into account the most severely involved ones, that guides our decision making about treatment. And it also guides how we assess the patients in follow up in clinic to see if they’re actually responding in terms of reduction of number of tender and swollen joints, reduction of enthesitis, reduction of dactylitis, reduction of spine pain, and reduction of skin and nail disease. And we have developed a criteria for minimal disease activity achievement, and this is something that we can now measure and use as a target for treatment in clinical practice.