Persistent inflammatory arthritis in patients with palindromic rheumatism most often developed in joints affected during earlier flares, with prior involvement associated with about two times the odds of progression in the same joint, according to a longitudinal study published in RMD Open.
Among 48 patients with complete joint-level data, 34 (71%) developed persistent inflammatory arthritis in at least one joint previously affected during a flare.
Researchers followed 63 patients with palindromic rheumatism who progressed to persistent inflammatory arthritis over a median of 13 months. Hands and shoulders were the most frequently involved sites at the initial flare, reported in 48% and 33% of patients, respectively, and small joints of the hands predominated across all flares.
At progression, 237 joints had synovitis; of these, 19% had been involved at the initial flare and 60% during subsequent flares.
The study also compared patients who progressed to rheumatoid arthritis following a palindromic rheumatism prodrome with anti–cyclic citrullinated peptide–positive at-risk patients who progressed without palindromic rheumatism. At rheumatoid arthritis onset, patients with a prodrome had higher 28–swollen joint counts (4.1 vs 3.2) but lower disability scores on the Health Assessment Questionnaire (0.79 vs 1.12), along with lower reported pain and fatigue. Disease activity scores were similar between groups.
The authors suggested that recurrent flares may contribute to adaptive changes in pain perception, potentially explaining the lower patient-reported burden despite greater objective joint inflammation.
To better understand this joint-level pattern, researchers conducted a single-center longitudinal analysis of patients from Leeds cohorts followed between 2008 and 2023, tracking joint involvement across flares and at progression to persistent inflammatory arthritis.
The findings suggest that clinicians may need to monitor previously affected joints more closely in patients with palindromic rheumatism, although the association does not establish causality. Notably, some joints, such as the feet, were infrequently involved during flares despite becoming affected at progression.
Limitations included potential recall bias for initial flares, incomplete joint-level data, and limited power for subgroup analyses.
"The strong joint-level association between PR and subsequent persistent arthritis suggests that local tissue-related factors may be critical in driving the transition," wrote first author Didem Sahin and senior author Kulveer Mankia of the Leeds Institute of Rheumatic and Musculoskeletal Medicine, University of Leeds, and colleagues, noting that this pattern may support therapies targeting the local joint environment.
Disclosures: One researcher reported receiving research funding, consulting fees, and honoraria from multiple companies. Another reported research grants and speaking fees. The remaining researchers reported no competing interests.
Source: RMD Open