Utility of NSAID Response Called Into Question for Longstanding AxSpA

TOPLINE:

Adults with axial spondyloarthritis (axSpA) with longstanding back pain symptoms had response rates to nonsteroidal anti-inflammatory drugs (NSAIDs) that were no different from patients with non-axSpA back pain of similar duration, according to findings from a prospective study.

METHODOLOGY:

The researchers recruited 233 consecutive outpatients with chronic back pain, including 68 with axSpA and 165 with non-axSpA back pain.

The mean ages of the participants in the axSpA and non-axSpA groups were 42.7 years and 49.3 years, respectively; symptom durations were approximately 15 years in both groups.

Participants were given NSAIDs and “any response” was defined as back pain improvement of more than two units on the Numerical Rating Scale, while “good response” was defined as an improvement of > 50% compared with baseline.

TAKEAWAY:

After 4 weeks, 30.9% of patients with axSpA and 29.1% of patients with non-axSpA back pain had any response, and 23.5% and 16.4% of patients with axSpA and non-axSpA back pain, respectively, had a good response.

The proportion of patients showing improvement ranged from 19% to 31% in both groups after 4 weeks of treatment.

No significant differences in response appeared in subgroups of patients based on inflammatory back pain stage or in different axSpA stages.

IN PRACTICE:

“We think that this information has an effect on clinical practice since a response to NSAIDs is an important criterion in the ASAS [Assessment of SpondyloArthritis international Society]/European Alliance of Associations for Rheumatology treatment recommendations that may influence decisions to initiate treatment with biologic or targeted-synthetic DMARDs [disease-modifying antirheumatic drugs]. Further, a good response to NSAIDs is also an important clinical feature in the ASAS classification criteria,” the researchers wrote.

SOURCE:

The lead author on the study was Xenofon Baraliakos, MD, of Ruhr University Bochum, Germany. The study was published online on January 15, 2024, in The Journal of Rheumatology.

LIMITATIONS:

The uneven sex match in the diagnoses and the history of NSAID treatment among patients in both groups were potential limiting factors. The researchers also noted that a similarly conducted study in patients with early disease could have findings that are “much different.”

DISCLOSURES:

The study was sponsored in part by Novartis. The researchers reported no relevant financial relationships.

A version of this article appeared on Medscape.com.