ACR/ARHP Annual Meeting 2012: Spondylarthritis Criteria Changing Landscape of the Disease

WASHINGTON, D.C.—The methods used to classify ankylosing spondylitis (AS) have changed dramatically in recent years, giving rise to a more nuanced view of the disease—a valuable clinical tool and a benefit to the patient, an expert said here at the 2012 ACR/ARHP Annual Meeting, held November 9–14 in Washington, D.C. [Editor’s Note: This session was recorded and is available via ACR SessionSelect at www.rheumatology.org.]

Désirée van der Heijde, MD, PhD, professor of rheumatology at Leiden University in the Netherlands, reviewed the new Assessment of SpondyloArthritis International Society (ASAS) classification criteria for axial spondylarthritis (SpA), which expanded the lens through which the disease is seen.¹ Dr. Van der Heijde also offered her thoughts on the best current treatment for AS, which continues to rely heavily on a combination of nonpharmacological and pharmacological (nonsteroidal antiinflammatory drugs [NSAIDs] and tumor necrosis factor [TNF] inhibitors) treatment.

Researchers are hoping for a way to identify AS patients earlier; on average, nine years pass from the time the first symptoms are felt to the time of diagnosis.

New Tools for Early Identification

When it comes to identifying AS, until 2009, the focus was mainly on the modified New York criteria. “When we used the modified New York criteria, we can only try to treat these patients when they have sacroilitis on the radiographs,” Dr. van der Heijde said. “But that’s not the way it starts. It starts earlier with back pain.”

Spondylarthritis is now subgrouped as either predominantly axial SpA or predominantly peripheral SpA—ankylosing spondylitis falls into the axial group.

With the ASAS criteria, there is less reliance on radiographic findings. When it comes to axial SpA, classification can be made if there is sacroiliitis on imaging along with at least one SpA feature—the list includes inflammatory back pain, arthritis, enthesitis in the heel, uveitis, dactylitis, psoriasis, Crohn’s disease, good response to NSAIDs, a family history for SpA, the presence of the HLA-B27 gene that has been linked to AS, and elevated C-reactive protein (CRP) levels. But a condition also qualifies as axial SpA if the HLA-B27 gene is present, along with at least two of those SpA features.¹

The shift away from relying so heavily on radiographic findings has led to more women being categorized as having axial SpA. Going by the patients participating in clinical trials, only about 25% of patients categorized using the modified New York criteria were women. But it’s now been found that, among those with nonradiographic axial SpA, 50% are women, Dr. van der Heijde said.