From the Guidelines
Elevated rheumatoid factor (RF) is a significant prognostic marker that indicates the presence of autoantibodies in the blood, and its presence, especially at high levels, is associated with a worse prognosis in rheumatoid arthritis (RA) patients, as stated in the 2010 EULAR recommendations 1.
Importance of RF in Diagnosis and Prognosis
The presence of RF is a crucial factor in the diagnosis and management of RA, as it is found in approximately 70-80% of RA patients. However, RF can also be elevated in other conditions, such as Sjögren's syndrome, systemic lupus erythematosus, chronic infections, and even in some healthy individuals, particularly older adults.
Treatment Decisions Based on RF and Other Factors
Treatment decisions for RA are based on clinical symptoms, physical examination findings, and the overall clinical picture, not solely on RF levels. According to the 2012 American College of Rheumatology recommendations update for the treatment of established rheumatoid arthritis, the presence of poor prognostic markers, including positive RF or anti-cyclic citrullinated peptide (CCP) antibodies, is a key factor in determining the treatment strategy 1.
Recommendations for Management
The 2015 American College of Rheumatology guideline for the treatment of rheumatoid arthritis emphasizes the importance of a treat-to-target approach, which involves adjusting treatment based on disease activity and other factors, including RF levels 1.
- Key points to consider in the management of elevated RF include:
- Further evaluation by a rheumatologist, including additional blood tests and imaging studies to assess for joint damage
- Interpretation of RF levels in the context of other clinical and laboratory findings to establish a diagnosis and guide treatment
- Consideration of the presence of poor prognostic markers, including RF, in determining the treatment strategy
- Use of a treat-to-target approach to adjust treatment based on disease activity and other factors.
From the Research
Elevated Rheumatoid Factor
- Elevated rheumatoid factor is often associated with rheumatoid arthritis, a systemic inflammatory arthritis that affects up to 1% of the worldwide population 2.
- The presence of a rheumatoid factor, along with other factors such as anti-citrullinated protein antibody, elevated C-reactive protein level, or elevated erythrocyte sedimentation rate, is consistent with a diagnosis of rheumatoid arthritis 2, 3.
- Rheumatoid arthritis can impact organs other than the joints, including lungs, skin, and eyes, and rapid diagnosis allows for earlier treatment with disease-modifying antirheumatic drugs, which is associated with better outcomes 2.
Diagnosis and Treatment
- Criteria for diagnosis of rheumatoid arthritis include having at least one joint with definite swelling that is not explained by another disease, and the likelihood of diagnosis increases with the number of small joints involved 3.
- Methotrexate is typically the first-line drug for rheumatoid arthritis, and biologic agents, such as tumor necrosis factor inhibitors, are generally considered second-line agents or can be added for dual therapy 3, 4.
- The goals of treatment include minimization of joint pain and swelling, prevention of radiographic damage and visible deformity, and continuation of work and personal activities 3.
Methotrexate Treatment
- Methotrexate has been shown to be effective in the treatment of rheumatoid arthritis, with statistically significant and clinically important differences observed for most efficacy outcomes 4.
- Methotrexate monotherapy has been shown to improve American College of Rheumatology (ACR) 50 response rate, physical function, and quality of life measures, and to reduce radiographic progression rates 4.
- However, methotrexate use is associated with a 16% discontinuation rate due to adverse events, and patients should be monitored for toxicity and side effects 4, 5.