Gary Macfarlane, MD, PhD: The Impact of Fibromyalgia on Treatment Response in PsA

In an interview with HCPLive, Gary Macfarlane, MD, PhD, dean of Interdisciplinary Research and Research Impact and clinical chair in Epidemiology at the University of Aberdeen, explained the impact of his study “The Influence of ‘Fibromyalgia-ness’ on Treatment Response Amongst Patients with Psoriatic Arthritis (PsA). Results from the British Society for Rheumatology Psoriatic Arthritis Register (BSR‐PsA),” presented at the American College of Rheumatology’s 2023 Convergence in San Diego, California.¹

Fibromyalgia is a significant research focus for Macfarlane’s group at the University of Aberdeen, as he led the European guidelines for managing fibromyalgia. He and his team aimed to investigate how fibromyalgia, either occurring alone or as a comorbidity with conditions like rheumatoid arthritis, axial spondyloarthritis, or psoriatic arthritis, influences response to biologic therapy. The study revealed that patients meeting fibromyalgia criteria or displaying fibromyalgia-like symptoms were less likely to meet standardized response criteria with biologic therapy.

While some clinicians believed biologics might alleviate fibromyalgia symptoms, the results of the study emphasized specific management for fibromyalgia is often necessary even alongside biologic therapy for psoriatic arthritis. Clinicians should be aware of the need for targeted fibromyalgia management if symptoms persist after biologic therapy. According to Macfarlane, incorporating fibromyalgia criteria into disease outcome measures, especially those self-reported by patients, is crucial for comprehensive assessment.

“The PsA response criteria does incorporate some patient measures is that a patient assessment of their condition within it,” he stated. “And of course, the fibromyalgia criteria can all be administered by self-report. So it's really these are really important ways to collect information directly from the patient.”

Considering the clinical importance and efficiency in completion, measuring fibromyalgia criteria is a valuable practice.

Regarding expectations for the future of rheumatology, Macfarlane hopes there is increased attention to pain in rheumatic diseases, as well as recognizing pain doesn't always equate to inflammation. Addressing pain comprehensively and understanding its origins beyond inflammation could pave the way for more targeted treatments.

References

1. ^{Macfarlane G, Rotariu O, Lembke S, Sunzini F, et al. The Influence of “Fibromyalgia-ness” on Treatment Response Amongst Patients with Psoriatic Arthritis (PsA). Results from the British Society for Rheumatology Psoriatic Arthritis Register (BSR‐PsA). Presented at: American College of Rheumatology Convergence 2023. San Diego, CA. November 10-15, 2023.}