Despite experiencing similar symptoms, people with non-radiographic axial spondyloarthritis (nr-axSpA) are less likely to be treated with a biologic therapy than those with ankylosing spondylitis (AS), according to a survey in the U.S.
The research was presented in a session, “Comparing Symptoms, Treatments Patterns, and Quality of Life of Non-radiographic Axial Spondyloarthritis and Ankylosing Spondylitis Patients: Findings from a US Survey,” at the recent 2019 American College of Rheumatology/Association for Rheumatology Professionals Annual Meeting, held in Atlanta.
Axial spondyloarthritis is a type of arthritis that predominantly affects the joints of the spine, causing chronic back pain. It is classified into two subtypes – AS if joint damage is visible through radiographs (X-rays) or nr-axSpA when no such abnormalities can be seen with this approach. Advances in magnetic resonance imaging have enabled the diagnosis of nr-axSpA in the clinic.
Researchers from Eli Lilly and Company, Adelphi Real World, and Oregon Health & Science University came together to better understand the symptoms, clinical characteristics, treatment patterns, and quality of life (QoL) of patients with nr-axSpA compared to those with AS.
The team analyzed data collected between June and August 2018 from a survey of patients and their rheumatologists in the U.S.
Data reported by physicians included demographics, disease status, symptoms, and medication use. The patients reported information on work disability and QoL.
Overall, the analysis included 88 rheumatologists, 515 individuals with AS, and 495 people with nr-axSpA.
Results showed that the group of nr-axSpA patients had a higher proportion of females (46.7% vs. 28.7% in the AS group), and was younger on average (44.2 years of age) compared to people with AS (46.3 years).
As for treatments, people with nr-axSpA were less likely to be prescribed a biologic compared to AS patients (59.6% vs. 73.6%).
On average, AS patients experienced slightly more symptoms at diagnosis. Still, a greater proportion of people with nr-axSpA experienced enthesitis — inflammation of the sites where tendons or ligaments insert into the bone (24.9% vs. 19.3% of the AS patients) — and synovitis, which refers to inflammation of the membrane that lines joints (20.6% vs. 13.1%).
Yet, similar results were found between the two groups in patient-reported outcomes: Assessment of SpondyloArthritis international Society Health Index (which measures disability, health, and functioning), Ankylosing Spondylitis Quality of Life, Bath Ankylosing Spondylitis Disease Activity Index, and the Work Productivity and Activity Impairment questionnaire.
“Nr-axSpA and AS, being part of the same disease spectrum (i.e. axial spondyloarthritis), share the same clinical features,” the researchers wrote. “The burden of the disease, as assessed by QoL measurements, is also similar … but despite these similarities, patients with nr-axSpA are less likely to be treated with a biologic.”
“The treatment approach for nr-axSpA needs to be similar to AS,” they added.