The use of ultrasound has significantly greater value than the use of composite clinical scores in the evaluation of disease activity in patients with psoriatic arthritis (PsA) and concomitant fibromyalgia syndrome (FMS), according to study results published in Annals of the Rheumatic Diseases.
Researchers sought to explore whether the use of ultrasound, as an objective imaging modality, can optimize the assessment of disease activity in patients with PsA and concomitant FMS.
Psoriatic arthritis was evaluated using 4 clinical disease activity indices: Minimal Disease Activity (MDA) in PsA, based on fulfillment of 5 or more of the 7 criteria, including tender joint count of 1 or lower, swollen joint count of 1 or lower, psoriasis severity area (PASI) of 1 or lower, patient pain on the Visual Assessment Scale (VAS) of 15 or lower, patient global disease activity on the VAS of 20 or lower, Health Assessment Questionnaire Disability Index (HAQ-DI) of 0.5 or lower, or tender entheseal points of 1 or lower; Disease Activity for Psoriatic Arthritis (DAPSA); Composite Psoriatic Disease Activity Index (CPDAI); and Psoriatic Arthritis Disease Activity Score (PASDAS). Fibromyalgia syndrome was evaluated using tender point count, Widespread Pain Index, and Symptom Severity Scale.
The current study was conducted at the Department of Rheumatology, Tel-Aviv Medical Center in Tel-Aviv, Israel. The study population included consecutive patients with PsA who had been enrolled prospectively between July 2018 and July 2020. All patients underwent ultrasound assessment, including 52 joints, 40 tendons, and 14 entheses. Ultrasound score was based on the summation of semiquantitative score, which included synovitis, tenosynovitis, and enthesitis.
A total of 156 patients completed the study, of whom 114 (73.1%) were in the PsA-without-FMS group and 42 (26.9%) were in the PsA-with-FMS group. Patients in the PsA-with-FMS group exhibited significantly increased scores in clinical composite indices, including MDA, CPDAI, DAPSI, and PASDAS (P <.001 for all). However, the total ultrasound score was similar among both patients with PsA with and without FMS. Results showed that the total ultrasound score was significantly associated with CPDAI, DAPSA, and PASDAS (P <.001) in the PsA-without-FMS group but not in the PsA-with-FMS group. In addition, the presence of FMS was significantly correlated with higher clinical scores (P <.001) but not with ultrasound score.
Study limitations included the cross-sectional design, the long mean PsA duration that may have affected findings of disease activity, and the lack of validation of the semiquantative ultrasound score.
Researchers concluded that, “[Ultrasound] has a significantly greater value than composite clinical scores in the assessment of disease activity in patients with [PsA with] FMS.”
Polachek A, Furer V, Zureik M, et al. Role of ultrasound for assessment of psoriatic arthritis patients with fibromyalgia. Ann Rheum Dis. Published online July 2, 2021. doi:10.1136/annrheumdis-2021-220562