High-Titer Rheumatoid Factor is Associated with Worse Clinical Outcomes and Higher Needs for Advanced Therapies in...

Area of Science:

• Rheumatology
• Immunology
• Clinical Medicine

Background:

• Rheumatoid factor (RF) is crucial in rheumatoid arthritis (RA) pathophysiology.
• The clinical impact of varying RF titers in RA is not well understood.
• This study investigates the association between different RF titers and clinical outcomes in established RA.

Purpose of the Study:

• To evaluate the associations between different rheumatoid factor (RF) titers and clinical outcomes in patients with long-standing rheumatoid arthritis (RA).
• To determine if high RF titers are linked to specific clinical characteristics and disease severity markers in RA.

Main Methods:

• A multicenter, cross-sectional study involving 1097 adult participants meeting 2010 ACR/EULAR criteria for RA.
• Assessment of circulating RF titers and clinical-epidemiological data.
• Statistical analyses included bivariate tests and multiple logistic/linear regression models.

Main Results:

• High RF titers (≥3x ULN) were observed in 56.2% of participants.
• Compared to non-high RF titers, high RF titers were associated with tobacco use, multiraciality, and higher BMI.
• High-titer RF independently predicted higher disease activity (CDAI), worse functional capacity (HAQ-DI), more extra-articular manifestations, and increased use of corticosteroids and bDMARDs.

Conclusions:

• High RF titers in long-standing RA are linked to adverse clinical outcomes, including greater disease activity, reduced physical function, and more extra-articular manifestations.
• Comparing high versus non-high RF titers provides more clinical utility than a simple positive/negative RF status.
• This titer-based approach should be considered in future RA research involving RF.