Comparison Between Haematological Parameters and Musculoskeletal Ultrasound Findings of Rheumatoid Arthritis Patients Recieving JAK Inhibitors Versus Traditional Treatment

Rheumatoid arthritis (RA) is a chronic autoimmune disease that affects about 1% of the world's population [1]. The disease is characterized by synovial membrane inflammation. The impact of RA on quality of life is significant, as it can lead to considerable disability, reduced mobility, and an increased risk of additional health complications [2].

CsDMARDs are the first-line drugs for RA treatment, of which methotrexate (MTX) is the cornerstone drug and monotherapy is recommended as the first choice (3).

However, previous studies had shown that 50% of RA patients had poor treatment effect on methotrexate or inadequate response to re-medication after relapse, resulting in drug resistance (4), resulting in no significant relief of symptoms and still high disease activity. EULAR had indicated that interleukin-6 (IL-6) receptor inhibitors and JAK inhibitors may have advantages over other biological disease-modifying anti-rheumatic drugs (bDMARDs) in patients who were not suitable for csDMARDs (5) Therefore, JAK inhibitors is used as monotherapy or combination therapy, which would provide a new strategy for clinical treatment. A few researches evaluated the relationship between PLT, RBC, Hb, red blood cells-platelet ratio (RPR), and the hemoglobin-platelet ratio (HPR) and RA disease activity. There is growing evidence that metrics like RDW and MPV, as well as the platelet-to-lymphocyte ratio (PLR), neutrophil-to-lymphocyte ratio (NLR), and others have been considered to be accurate, reliable inflammatory biomarkers in autoimmune illnesses[6,7] US has proven itself to be a useful imaging method for assessing articular and periarticular inflammation in small and large joints throughout the last years High resolution musculoskeletal ultrasound (MSUS), incorporating power Doppler ultrasound (PDUS), has demonstrated to be significantly more accurate than clinical evaluation in visualizing the inflammatory process. Furthermore, relatively few studies have examined ankle joint involvement in individuals with RA who lack symptoms [8].