Palindromic Rheumatism Frequently Precedes Early Rheumatoid Arthritis: Results From an Incident Cohort

Area of Science:

• Rheumatology
• Clinical Epidemiology

Background:

• Early rheumatoid arthritis (ERA) diagnosis can be preceded by episodic joint inflammation, a condition also known as palindromic rheumatism.
• Understanding the frequency and characteristics of patients with prior episodic symptoms is crucial for early diagnosis and management of ERA.

Purpose of the Study:

• To determine the prevalence of self-reported episodic joint inflammation in patients diagnosed with early rheumatoid arthritis (ERA).
• To identify sociodemographic and clinical factors that differentiate ERA patients with a history of episodic joint inflammation from those without.

Main Methods:

• A multicenter incident cohort study involving 154 early rheumatoid arthritis (RA) patients from the Canadian Early ArThritis CoHort (CATCH) between April 2017 and March 2018.
• Statistical analyses included chi-square and t-tests for comparisons and multivariable logistic regression to identify associated factors.
• Case report forms were used to collect data on joint pain and swelling preceding ERA diagnosis.

Main Results:

• 42% of ERA patients reported a history of episodic joint pain and swelling, with half experiencing these symptoms over 6 months prior to diagnosis.
• ERA patients with prior episodic joint inflammation were more frequently female, had higher incomes, were seropositive, and presented with more comorbidities.
• These patients also exhibited fewer swollen joints and lower Clinical Disease Activity Index (CDAI) scores at the time of ERA diagnosis.

Conclusions:

• Episodic joint inflammation is a common preceding symptom in a significant proportion of early rheumatoid arthritis patients.
• Specific patient characteristics, including being female, higher income, and milder initial disease presentation, are associated with this preceding symptom pattern.