Atul Deodhar, MD: Treatment Disparities in nr-axSpA and Ankylosing Spondylitis

Despite being within the same disease spectrum, a new study has found patients with ankylosing spondylitis and non-radiographic axial spondyloarthritis (nr-axSpA) receive different treatment despite similar disease burden and symptoms.

Results of the study, which were presented at the 2019 American College of Rheumatology annual meeting in Atlanta, GA, revealed patients with nr-axSpA were less likely to be prescribed biologics and called for steps to change this.

To assess differences in symptoms, investigators performed a cross-sectional survey with rheumatologists and their patients in the US. All patients who had physical confirmed diagnoses of either condition were eligible for inclusion in the trial.

Information including demographics, disease status, symptoms and medication were reported by physicians, but work disability and quality of life measurements were reported by the patients through a questionnaire. Investigators performed subsequent parametric and non-parametric tests to compare quality of life and treatment patterns of each disease.

From 88 rheumatologists, a cohort of 515 ankylosing spondylitis patients and 495 nr-axSpA patients were included in the analysis. Investigators noted a greater proportion of nr-axSpA patients were women (46.7% versus 28.7%, P< 0.0001) and had a younger mean age (44.2 versus 46.3, P=0.014) than their counterparts with ankylosing spondylitis.

Upon analyses, investigators observed patients with nr-axSpA were less likely to be prescribed a biologic than patients with ankylosing spondylitis. Additionally, investigators noted patients with ankylosing spondylitis experienced slightly less symptoms (2.31 versus 2.61, P=0.023) but more nr-axSpA patients reported to experience enthesitis(24.9% versus 19.3%, P=0.048) and synovitis (20.6% versus 13.1%, P=0.003).

When examining patient reported outcomes, investigators noted scores on multiple assessments produced similar results including the Assessment of SpondyloArthritis international Society Health Index (5.24 versus 5.74, P=0.171), Ankylosing Spondylitis Quality of Life (5.81 versus 6.29, P=0.296), Bath Ankylosing Spondylitis Disease Activity Index (2.92 versus 3.19, P=0.124).

For more on the clinical impact of this information, MD Magazine sat down with investigator Atul Deodhar, MD, professor of medicine in the Division of Arthritis and Rheumatic Diseases at the Oregon Health and Science University, for his takeaways from study results.

MD Mag: What did you find when comparing symptoms, treatment patterns, and quality of life in patients with nr-axSpA and AS?

Deodhar: This was a comparison. This was a large study done. It was a cross sectional study done in the United States, 88 rheumatologists participated in that patients participated in that. Half the patients were ankylosing spondylitis, half the patient were non-radiographic axial spondylitis. The questions were, what is the burden of the disease number 1, and what kind of medications do these patients receive?

There were lots of patient reported outcomes, which the patients filled out. Only patients who have rheumatologists proven diagnosis of ankylosing spondylitis or non-radiographic axial spondylitis, were allowed to participate and they were roughly about 500 in each group, and as I said 88 rheumatologists.

What was found out interestingly was the symptom burden and the disease burden was equal in both ankylosing spondylitis and non-radiographic axial spondylitis. However, the difference was a substantially less number of patients who are non-radiographic were treated with biologics. So, for the same amount of burden patients are not being treated, not being taken seriously because they don't have definitive ankylosing spondylitis. And that's why they're not being treated with biologics the way they should, for the same amount of burden that they have with or equal burden like ankylosing spondylitis. That was an eye opener and that is an important study.