A possible new phase for rheumatoid arthritis treatment

The pathology of rheumatoid arthritis within the first few months after symptom onset is distinct from that of the early phases of other inflammatory joint diseases and also of established rheumatoid arthritis. New research published today in Arthritis Research & Therapy found that very early rheumatoid arthritis is characterised by a distinct profile of T cell, macrophage and stromal cell related cytokines in synovial fluid.

This finding of a distinct phase of rheumatoid arthritis, immediately after the onset of clinical symptoms, provides a new rationale for the very early treatment of rheumatoid arthritis – before the disease develops into a long-term condition.

The synovium, the connective tissue membrane that lines the joints, is the primary site of pathology in rheumatoid arthritis. Although the processes that maintain long-term inflammation of the synovium in rheumatoid arthritis have been well studied, those initiating the inflammation have not, and very few groups have studied the pathology of rheumatoid arthritis within the first few weeks after the onset of symptoms.

Karim Raza and colleagues, from the University of Birmingham, U.K., investigated the processes occurring in the joints of patients within 3 months of the onset of clinical symptoms. They assessed a panel of T cell, macrophage and stromal cell related cytokines and chemokines in synovial fluid samples from inflamed joints of these patients with very early arthritis. Patients who eventually developed persistent rheumatoid arthritis had a cytokine profile that was different from that seen in patients in the early phases of other arthritic diseases, and also from that in longstanding rheumatoid arthritis – suggesting a distinct pathological process during the early phase of rheumatoid arthritis.

Rheumatoid arthritis is a common, serious and disabling autoimmune disease in which inflammation of the joint lining (or synovium) results when the body’s tissues are mistakenly attacked by the immune system. Approximately eight million people are affected by rheumatoid arthritis in the UK.

Raza and colleagues speculate that the cytokines present in very early rheumatoid arthritis may be involved in the development of the microenvironment required for chronic disease. The authors propose that there is now a strong biological rationale for testing the effects of potent anti-inflammatory therapies during the first few months of clinically apparent disease. “The pathologically distinct nature of the very early phase of clinically apparent rheumatoid arthritis suggests that this phase may represent a therapeutic window”, said Dr Karim Raza.